FFPROBE-ALL(1)
๐ธ NAME ๐ธ
okay bestie, this is FFPROBE-ALL(1), aka the manual page for ffprobe โ literally โffprobe media prober,โ and yes itโs giving main-character energy for media inspection ๐
โจ
โจ SYNOPSIS โจ
ffprobe [options] input_url
๐ฆ DESCRIPTION ๐ฆ
ffprobe gathers info from multimedia streams and prints it in human- and machine-readable fashion. slay for both humans and scripts ๐
for example, it can be used to check the format of the container used by a multimedia stream, and the format and type of each media stream contained in it. iykyk, itโs the vibe check for containers + streams ๐ฅ
if a url is specified in input, ffprobe will try to open and probe the url content. if the url cannot be opened or recognized as a multimedia file, a positive exit code is returned. periodt ๐
if no output is specified as output with o, ffprobe will write to stdout. no cap, thatโs the default bestie ๐ซถ
ffprobe may be employed both as a standalone application or in combination with a textual filter, which may perform more sophisticated processing, e.g. statistical processing or plotting. itโs giving โworks alone and works with your bestieโ energy ๐
options are used to list some of the formats supported by ffprobe, or for specifying which information to display, and for setting how ffprobe will show it. literally the whole control panel ๐
ffprobe output is designed to be easily parsable by a textual filter, and consists of one or more sections of a form defined by the selected writer, which is specified by the output_format option. yes, the writer chooses the shape of the output โ iconic โญ
sections may contain other nested sections, and are identified by a name (which may be shared by other sections), and an unique name. see the output of sections. nested sections are lowkey a whole aesthetic ๐
metadata tags stored in the container or in the streams are recognized and printed in the corresponding "FORMAT", "STREAM", "STREAM_GROUP_STREAM" or "PROGRAM_STREAM" section. all the little tags get their moment ๐
๐ OPTIONS ๐
all the numerical options, if not specified otherwise, accept a string representing a number as input, which may be followed by one of the SI unit prefixes, for example: 'K', 'M', or 'G'. numbers with cute little suffixes, we love to see it โจ
if i is appended to the SI unit prefix, the complete prefix will be interpreted as a unit prefix for binary multiples, which are based on powers of 1024 instead of powers of 1000. appending B to the SI unit prefix multiplies the value by 8. this allows using, for example: 'KB', 'MiB', 'G' and 'B' as number suffixes. math but make it fashion ๐ง
options which do not take arguments are boolean options, and set the corresponding value to true. they can be set to false by prefixing the option name with "no". for example using -nofoo will set the boolean option with name "foo" to false. flippity flip, no cap ๐ฆ
options that take arguments support a special syntax where the argument given on the command line is interpreted as a path to the file from which the actual argument value is loaded. to use this feature, add a forward slash '/' immediately before the option name (after the leading dash). e.g.
ffmpeg -i INPUT -/filter:v filter.script OUTPUT
will load a filtergraph description from the file named filter.script. reading args from a file is such a flex ๐
๐ Stream specifiers ๐
some options are applied per-stream, e.g. bitrate or codec. stream specifiers are used to precisely specify which stream(s) a given option belongs to. basically: tell ffprobe exactly which stream youโre obsessed with ๐
a stream specifier is a string generally appended to the option name and separated from it by a colon. e.g. -codec:a:1 ac3 contains the "a:1" stream specifier, which matches the second audio stream. therefore, it would select the ac3 codec for the second audio stream. targeted, specific, iconic ๐ฏ
a stream specifier can match several streams, so that the option is applied to all of them. e.g. the stream specifier in -b:a 128k matches all audio streams. group chat for audio streams only fr fr ๐ซถ
an empty stream specifier matches all streams. for example, -codec copy or -codec: copy would copy all the streams without reencoding. empty specifier = everyoneโs invited ๐
possible forms of stream specifiers are:
stream_indexโ matches the stream with this index. e.g.-threads:1 4would set the thread count for the second stream to4. ifstream_indexis used as an additional stream specifier (see below), then it selects stream numberstream_indexfrom the matching streams. stream numbering is based on the order of the streams as detected bylibavformatexcept when a stream group specifier or program ID is also specified. in this case it is based on the ordering of the streams in the group or program. numbering lore, but make it clear โจstream_type[:additional_stream_specifier]โstream_typeis one of following:'v'or'V'for video,'a'for audio,'s'for subtitle,'d'for data, and't'for attachments.'v'matches all video streams,'V'only matches video streams which are not attached pictures, video thumbnails or cover arts. ifadditional_stream_specifieris used, then it matches streams which both have this type and match theadditional_stream_specifier. otherwise, it matches all streams of the specified type. type matching but make it cute ๐g:group_specifier[:additional_stream_specifier]โ matches streams which are in the group with the specifiergroup_specifier. ifadditional_stream_specifieris used, then it matches streams which both are part of the group and match theadditional_stream_specifier.group_specifiermay be one of the following:group_indexโ match the stream with this group index.#group_idori:group_idโ match the stream with this group id.
p:program_id[:additional_stream_specifier]โ matches streams which are in the program with the idprogram_id. ifadditional_stream_specifieris used, then it matches streams which both are part of the program and match theadditional_stream_specifier. program-specific, no cap ๐#stream_idori:stream_idโ match the stream by stream id (e.g. PID in MPEG-TS container). stream id said โthis is meโ ๐m:key[:value]โ matches streams with the metadata tagkeyhaving the specifiedvalue. ifvalueis not given, matches streams that contain the given tag with any value. the colon character':'inkeyorvalueneeds to be backslash-escaped. metadata matchmaking, but be careful with that colon bestie ๐ญdisp:dispositions[:additional_stream_specifier]โ matches streams with the given disposition(s).dispositionsis a list of one or more dispositions (as printed by the-dispositionsoption) joined with'+'. disposition list said slay ๐ธuโ matches streams with usable configuration, the codec must be defined and the essential information such as video dimension or audio sample rate must be present. usable config only, we donโt do mystery streams ๐
lowkey important: note that in ffmpeg, matching by metadata will only work properly for input files.
๐ Generic options ๐
these options are shared amongst the ff* tools. group-chat shared options, cute ๐ซถ
-L,-licenseโ show license.-h,-?,-help,--help [arg]โ show help. an optional parameter may be specified to print help about a specific item. if no argument is specified, only basic (non advanced) tool options are shown. help me help you ๐
possible values of arg are:
longโ print advanced tool options in addition to the basic tool options.fullโ print complete list of options, including shared and private options for encoders, decoders, demuxers, muxers, filters, etc.decoder=decoder_nameโ print detailed information about the decoder nameddecoder_name. use the-decodersoption to get a list of all decoders.encoder=encoder_nameโ print detailed information about the encoder namedencoder_name. use the-encodersoption to get a list of all encoders.demuxer=demuxer_nameโ print detailed information about the demuxer nameddemuxer_name. use the-formatsoption to get a list of all demuxers and muxers.muxer=muxer_nameโ print detailed information about the muxer namedmuxer_name. use the-formatsoption to get a list of all muxers and demuxers.filter=filter_nameโ print detailed information about the filter namedfilter_name. use the-filtersoption to get a list of all filters.bsf=bitstream_filter_nameโ print detailed information about the bitstream filter namedbitstream_filter_name. use the-bsfsoption to get a list of all bitstream filters.protocol=protocol_nameโ print detailed information about the protocol namedprotocol_name. use the-protocolsoption to get a list of all protocols.
-versionโ show version.-buildconfโ show the build configuration, one option per line.-formatsโ show available formats (including devices).-demuxersโ show available demuxers.-muxersโ show available muxers.-devicesโ show available devices.-codecsโ show all codecs known tolibavcodec. note that the term'codec'is used throughout this documentation as a shortcut for what is more correctly called a media bitstream format. codec said โtechnicallyโฆโ ๐-decodersโ show available decoders.-encodersโ show all available encoders.-bsfsโ show available bitstream filters.-protocolsโ show available protocols.-filtersโ show availablelibavfilterfilters.-pix_fmtsโ show available pixel formats.-sample_fmtsโ show available sample formats.-layoutsโ show channel names and standard channel layouts.-dispositionsโ show stream dispositions.-colorsโ show recognized color names.-sources device[,opt1=val1[,opt2=val2]...]โ show autodetected sources of the input device. some devices may provide system-dependent source names that cannot be autodetected. the returned list cannot be assumed to be always complete.
ffmpeg -sources pulse,server=192.168.0.4
-sinks device[,opt1=val1[,opt2=val2]...]โ show autodetected sinks of the output device. some devices may provide system-dependent sink names that cannot be autodetected. the returned list cannot be assumed to be always complete.
ffmpeg -sinks pulse,server=192.168.0.4
-loglevel [flags+]loglevel|-v [flags+]loglevelโ set logging level and flags used by the library.
the optional flags prefix can consist of the following values:
repeatโ indicates that repeated log output should not be compressed to the first line and the"Last message repeated n times"line will be omitted.levelโ indicates that log output should add a"[level]"prefix to each message line. this can be used as an alternative to log coloring, e.g. when dumping the log to file.timeโ indicates that log lines should be prefixed with time information.datetimeโ indicates that log lines should be prefixed with date and time information.
flags can also be used alone by adding a '+'/'-' prefix to set/reset a single flag without affecting other flags or changing loglevel. when setting both flags and loglevel, a '+' separator is expected between the last flags value and before loglevel.
quiet,-8โ show literally nothing. Silent mode. ๐คซ Like, not a peep.panic,0โ only fatal errors that could actually crash the process, like an assertion failure. Ngl this one isn't currently used for anything.fatal,8โ only fatal errors. These are the errors where the process absolutely cannot keep going. Periodt.error,16โ shows all errors, even the ones it can recover from.warning,24โ shows all warnings and errors. Anything about a possibly incorrect or unexpected event shows up here.info,32โ shows informative messages while processing. This is on top of warnings and errors. This is the default value, bestie.verbose,40โ same asinfobut, like, more verbose. Obviously.debug,48โ shows everything, including debugging info. The full tea. ๐ซtrace,56โ yeah, that's the whole entry. ๐
So for example, to enable repeated log output, add the level prefix and set loglevel to verbose:
ffmpeg -loglevel repeat+level+verbose -i input output
And another example that turns on repeated log output without touching the current state of the level prefix flag or loglevel:
ffmpeg [...] -loglevel +repeat
By default the program logs to stderr. If your terminal supports coloring, colors get used to mark errors and warnings. ๐ You can turn log coloring off by setting the environment variable AV_LOG_FORCE_NOCOLOR, or force it on by setting AV_LOG_FORCE_COLOR.
-reportโ dumps the full command line and the log output into a file namedprogram-YYYYMMDD-HHMMSS.login the current directory. This file is genuinely useful for bug reports, fr fr. It also implies-loglevel debug.
Setting the environment variable FFREPORT to any value has the same effect. If the value is a :-separated key=value sequence, those options will affect the report; option values must be escaped if they contain special characters or the options delimiter : (see the ``Quoting and escaping'' section in the ffmpeg-utils manual).
These are the options it recognizes:
fileโ set the file name to use for the report;%pis expanded to the name of the program,%tis expanded to a timestamp, and%%is expanded to a plain%. โจlevelโ set the log verbosity level using a numerical value (see-loglevel).
For example, to output a report to a file named ffreport.log using a log level of 32 (the alias for log level info):
FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output
Errors in parsing the environment variable are not fatal, and they won't appear in the report either.
-hide_bannerโ suppresses printing the banner. All FFmpeg tools normally show a copyright notice, build options and library versions, and this option is how you shut all that off. ๐-cpuflags flags(global) โ lets you set and clear cpu flags. Heads up: this option is intended for testing. Do not use it unless you know what you're doing, no cap.
ffmpeg -cpuflags -sse+mmx ...
ffmpeg -cpuflags mmx ...
ffmpeg -cpuflags 0 ...
Possible flags for this option are:
- x86
mmxmmxextssesse2sse2slowsse3sse3slowssse3atomsse4.1sse4.2avxavx2xopfma3fma43dnow3dnowextbmi1bmi2cmov
- ARM
armv5tearmv6armv6t2vfpvfpv3neonsetend
- AArch64
armv8vfpneon
- PowerPC
altivec
- Specific Processors
pentium2pentium3pentium4k6k62athlonathlonxpk8
-cpucount count(global) โ overrides detection of CPU count. Same warning as above: this option is intended for testing. Do not use it unless you know what you're doing, bestie. ๐
ffmpeg -cpucount 2
-max_alloc bytesโ sets the maximum size limit for allocating a block on the heap by ffmpeg's family of malloc functions. > Exercise extreme caution when using this option. Don't use it if you don't understand the full consequence of doing so. Default isINT_MAX.
โจ AVOptions โจ
These options are provided directly by the libavformat, libavdevice and libavcodec libraries. Wanna see the list of available AVOptions? Use the -help option. They come split into two categories:
- generic โ these can be set for any container, codec or device. Generic options are listed under
AVFormatContextoptions for containers/devices and underAVCodecContextoptions for codecs. - private โ these are specific to the given container, device or codec. Private options are listed under their corresponding containers/devices/codecs. ๐
Example time โ to write an ID3v2.3 header instead of a default ID3v2.4 into an MP3 file, use the id3v2_version private option of the MP3 muxer:
ffmpeg -i input.flac -id3v2_version 3 out.mp3
All codec AVOptions are per-stream, so you gotta attach a stream specifier to them:
ffmpeg -i multichannel.mxf -map 0:v:0 -map 0:a:0 -map 0:a:0 -c:a:0 ac3 -b:a:0 640k -ac:a:1 2 -c:a:1 aac -b:2 128k out.mp4
In that example, a multichannel audio stream is mapped twice for output. The first instance is encoded with codec ac3 and bitrate 640k. The second instance is downmixed to 2 channels and encoded with codec aac. A bitrate of 128k is specified for it using the absolute index of the output stream. ๐
Note: the-nooptionsyntax cannot be used for boolean AVOptions, use-option 0/-option 1instead.
Note: the old undocumented way of specifying per-stream AVOptions by prependingv/a/sto the options name is now obsolete and will be removed soon. ๐
๐ Main options ๐
-f formatโ force the format to use.-unitโ show the unit of the displayed values.-prefixโ use SI prefixes for the displayed values. Unless the-byte_binary_prefixoption is used, all the prefixes are decimal.-byte_binary_prefixโ force the use of binary prefixes for byte values.-sexagesimalโ use sexagesimal formatHH:MM:SS.MICROSECONDSfor time values. โฑ๏ธ-prettyโ prettify the format of the displayed values. It corresponds to the options-unit -prefix -byte_binary_prefix -sexagesimal. It's giving "all the glow-up flags at once" โจ-output_format,-of,-print_format writer_name[=writer_options]โ set the output printing format.
writer_name specifies the name of the writer, and writer_options specifies the options to be passed to the writer.
So for example, to print the output in JSON format, specify:
-output_format json
For more details on the available output printing formats, see the Writers section below.
-sectionsโ print sections structure and section information, then exit. Heads up: the output is not meant to be parsed by a machine.-select_streams stream_specifierโ select only the streams specified by stream_specifier. This option affects only the options related to streams (e.g.show_streams,show_packets, etc.).
For example, to show only audio streams, you can use the command:
ffprobe -show_streams -select_streams a INPUT
To show only video packets belonging to the video stream with index 1:
ffprobe -show_packets -select_streams v:1 INPUT
-show_dataโ show payload data, as a hexadecimal and ASCII dump (other formats can be selected using-data_dump_format). Coupled with-show_packets, it'll dump the packets' data. Coupled with-show_streams, it'll dump the codec extradata. ๐ง
The dump is printed as the data field. It may contain newlines.
-show_data_hash algorithmโ show a hash of payload data, for packets with-show_packetsand for codec extradata with-show_streams.-data_dump_format formatโ select a format used for the data dumps enabled with the-show_dataoption. The default isxxd, which is a hexdump format compatible with the well-knownxxdprogram.base64is also supported.-show_errorโ show information about the error found when trying to probe the input.
The error information is printed within a section with name ERROR. ๐ญ
-show_formatโ show information about the container format of the input multimedia stream.
All the container format information is printed within a section with name FORMAT.
-show_entries section_entriesโ set the list of entries to show.
Entries are specified according to the following syntax. section_entries contains a list of section entries separated by :. Each section entry is composed of a section name (or unique name), optionally followed by a list of entries local to that section, separated by ,.
If a section name is specified but is followed by no =, all entries are printed to output, together with all the contained sections. Otherwise only the entries specified in the local section entries list are printed. In particular, if = is specified but the list of local entries is empty, then no entries will be shown for that section.
Note that the order of specification of the local section entries is not honored in the output โ the usual display order gets retained. ๐
The formal syntax is given by:
<LOCAL_SECTION_ENTRIES> ::= <SECTION_ENTRY_NAME>[,<LOCAL_SECTION_ENTRIES>]
<SECTION_ENTRY> ::= <SECTION_NAME>[=[<LOCAL_SECTION_ENTRIES>]]
<SECTION_ENTRIES> ::= <SECTION_ENTRY>[:<SECTION_ENTRIES>]
For example, to show only the index and type of each stream, and the PTS time, duration time, and stream index of the packets, you can specify the argument:
packet=pts_time,duration_time,stream_index : stream=index,codec_type
To show all the entries in the section format, but only the codec type in the section stream, specify the argument:
format : stream=codec_type
To show all the tags in the stream and format sections:
stream_tags : format_tags
To show only the title tag (if available) in the stream sections:
-show_packetsโ bestie, this dumps info about every single packet chilling inside the input multimedia stream ๐ฆ. Each packet gets its own little solo moment in a section literally named"PACKET". Iconic behavior.-show_framesโ shows you the tea on every frame and subtitle in the input multimedia stream ๐ฌ. Every single frame gets printed in its own dedicated section named"FRAME"or"SUBTITLE"(yep, subtitles get their own label, we love that for them).-show_log loglevelโ surfaces the logging info from the decoder for each frame, based on whatever you set inloglevel(peep-loglevel) ๐. Heads up though: this one requires-show_framesor it simply won't do anything. Each log message shows up in its own dedicated section called"LOG".-show_streamsโ spills all the info about each media stream in the input multimedia stream ๐. Every stream's info lands in a dedicated section named"STREAM".-show_programsโ shows info about the programs and the streams inside them contained in the input multimedia stream ๐บ. Each media stream's info gets a dedicated section named"PROGRAM_STREAM".-show_stream_groupsโ same energy but for stream groups and the streams they contain ๐ซ. Each media stream's info is printed within a dedicated section named"STREAM_GROUP_STREAM".-show_chaptersโ shows info about the chapters stored in the format ๐. Every chapter gets printed within a dedicated section named"CHAPTER".-count_framesโ literally counts how many frames each stream has and reports the number inside that stream's own section ๐ข. No cap, it's just counting.-count_packetsโ same vibe, but counting packets per stream and reporting it in the corresponding stream section ๐.-read_intervals read_intervalsโ only read the intervals you actually want, queen ๐.read_intervalshas to be a sequence of interval specs separated by",".ffprobewill seek to the interval's starting point and keep reading from there.
Every interval is made of two optional parts, separated by "%".
Part one = the interval start position ๐ฏ. It's read as an absolute position, or as a relative offset from the current position if it's preceded by the "+" character. If you don't specify this first part at all, then no seeking happens when reading this interval.
Part two = the interval end position ๐. Also read as absolute, or as a relative offset from the current position if it starts with "+". But here's the plot twist: if that offset specification starts with "#", it's interpreted as the number of packets to read (and no, the flushing packets don't count) starting from the interval's start. And if you skip the second part entirely, the program just reads until the end of the input. Simple as.
Lowkey important: seeking is not accurate, so the actual interval start point may differ from the position you specified ๐ญ. Also, when you give an interval duration, the absolute end time is computed by adding the duration to the interval start point found by seeking the file โ not to the start value you specified. So don't come for her when the numbers look off.
The formal syntax is given by:
<INTERVAL> ::= [<START>|+<START_OFFSET>][%[<END>|+<END_OFFSET>]]
<INTERVALS> ::= <INTERVAL>[,<INTERVALS>]
A few examples follow, because we're nice like that ๐
- Seek to time
10, read packets until20seconds after the found seek point, then seek to position"01:30"(1 minute and thirty seconds) and read packets until position"01:45":
10%+20,01:30%01:45
- Read only
42packets after seeking to position"01:23":
01:23%+#42
- Read only the first
20seconds from the start:
%+20
- Read from the start until position
"02:30":
%02:30
-show_private_data,-privateโ shows private data, aka data that depends on the format of whatever particular element is being shown ๐. This one is enabled by default, but you might need to turn it off for specific uses โ for example when you're creating XSD-compliant XML output. Do with that what you will.-show_program_versionโ shows info related to the program version ๐ท๏ธ. That version info is printed within a section named"PROGRAM_VERSION".-show_library_versionsโ shows info related to library versions ๐. Version info for each library is printed within a section named"LIBRARY_VERSION".-show_versionsโ shows info related to both program and library versions, bestie โจ. It's the equivalent of setting both-show_program_versionand-show_library_versionsat the same time. Two birds, one slay.-show_pixel_formatsโ shows info about all the pixel formats FFmpeg supports ๐จ. Pixel format info for each format gets printed within a section named"PIXEL_FORMAT".-show_optional_fields valueโ okay so some writers (viz. JSON and XML) just omit printing fields that have invalid or non-applicable values, while other writers always print them ๐ค. This option lets you control that behaviour. Valid values are"always"/1,"never"/0, and"auto"/-1. Default isauto.-analyze_framesโ analyzes frames and/or their side data up to whatever read interval you provided, handing you extra info that may be useful at the stream level ๐ง โจ. It must be paired with the-show_streamsoption or it will have absolutely no effect (sorry, them's the rules).
Currently, the extra fields this option provides when enabled are the "closed_captions" and "film_grain" fields.
For example, to analyze the first 20 seconds and populate these fields:
ffprobe -show_streams -analyze_frames -read_intervals "%+20" INPUT
-bitexactโ forces bitexact output ๐ฏ. Super useful when you want to produce output that isn't dependent on the specific build.-i input_urlโ readsinput_url๐ฅ.-o output_urlโ writes output tooutput_url๐ค. If you don't specify it, the output gets sent tostdout.-c:media_specifier codec_name,-codec:media_specifier codec_nameโ forces a specific decoder implementation for the stream identified bymedia_specifier๐๏ธ. That specifier can take the values"a"(audio),"v"(video),"s"(subtitle), and"d"(data). Pick your fighter.
๐ WRITERS ๐
okay so bestie, a writer is literally the output-format main character for ffprobe โ it defines the output format that ffprobe adopts, and it gets used for printing, like, all the parts of the output. slay.
A writer may accept one or more arguments, and those arguments specify the options to adopt. The options are specified as a list of key=value pairs, separated by :.
All writers support the following options:
string_validation,svโ set the string validation mode. these are the accepted values:failโ the writer will fail immediately in case an invalid string (UTF-8) sequence or code point is found in the input. this is especially useful to validate input metadata.ignoreโ any validation error will be ignored. this will result in possibly broken output, especially with thejsonorxmlwriter. ๐replaceโ the writer will substitute invalid UTF-8 sequences or code points with the string specified with thestring_validation_replacement.
Default value is replace.
string_validation_replacement,svrโ set the replacement string to use in casestring_validationis set toreplace.
In case the option is not specified, the writer will assume the empty string, that is it will remove the invalid sequences from the input strings. ๐ซถ
A description of the currently available writers follows.
๐ง default ๐ง
Default format.
Print each section in the form:
[SECTION]
key1=val1
...
keyN=valN
[/SECTION]
Metadata tags are printed as a line in the corresponding FORMAT, STREAM, STREAM_GROUP_STREAM or PROGRAM_STREAM section, and are prefixed by the string TAG:.
A description of the accepted options follows.
nokey,nkโ if set to1specify not to print the key of each field. Default value is0.noprint_wrappers,nwโ if set to1specify not to print the section header and footer. Default value is0.
๐ compact, csv ๐
Compact and CSV format.
The csv writer is equivalent to compact, but supports different defaults.
Each section is printed on a single line. If no option is specified, the output has the form:
section|key1=val1| ... |keyN=valN
Metadata tags are printed in the corresponding format or stream section. A metadata tag key, if printed, is prefixed by the string tag:.
The description of the accepted options follows.
item_sep,sโ specify the character to use for separating fields in the output line. It must be a single printable character, it is|by default (,for thecsvwriter).nokey,nkโ if set to1specify not to print the key of each field. Its default value is0(1for thecsvwriter).escape,eโ set the escape mode to use, default toc(csvfor thecsvwriter).
It can assume one of the following values:
cโ perform C-like escaping. Strings containing a newline (\n), carriage return (\r), a tab (\t), a form feed (\f), the escaping character (\) or the item separator characterSEPare escaped using C-like fashioned escaping, so that a newline is converted to the sequence\n, a carriage return to\r,\to\\and the separatorSEPis converted to\SEP.csvโ perform CSV-like escaping, as described in RFC4180. Strings containing a newline (\n), a carriage return (\r), a double quote ("), orSEPare enclosed in double-quotes.noneโ perform no escaping.
print_section,pโ print the section name at the beginning of each line if the value is1, disable it with value set to0. Default value is1.
๐ flat ๐
Flat format.
A free-form output where each line contains an explicit key=value, such as streams.stream.3.tags.foo=bar. The output is shell escaped, so it can be directly embedded in sh scripts as long as the separator character is an alphanumeric character or an underscore (see sep_char option).
The description of the accepted options follows.
sep_char,sโ separator character used to separate the chapter, the section name, IDs and potential tags in the printed field key.
Default value is ..
hierarchical,hโ specify if the section name specification should be hierarchical. If set to1, and if there is more than one section in the current chapter, the section name will be prefixed by the name of the chapter. A value of0will disable this behavior.
Default value is 1.
๐ ini ๐
INI format output.
Print output in an INI based format.
The following conventions are adopted:
- all key and values are UTF-8
.is the subgroup separator- newline,
\t,\f,\band the following characters are escaped \is the escape character#is the comment indicator=is the key/value separator:is not used but usually parsed as key/value separator
This writer accepts options as a list of key=value pairs, separated by :.
The description of the accepted options follows.
hierarchical,hโ specify if the section name specification should be hierarchical. If set to1, and if there is more than one section in the current chapter, the section name will be prefixed by the name of the chapter. A value of0will disable this behavior.
Default value is 1.
โจ json โจ
JSON based format.
Each section is printed using JSON notation.
The description of the accepted options follows.
compact,cโ if set to1enable compact output, that is each section will be printed on a single line. Default value is0.
For more information about JSON, see <http://www.json.org/>.
๐ฆ xml ๐ฆ
XML based format.
The XML output is described in the XML schema description file ffprobe.xsd installed in the FFmpeg datadir.
An updated version of the schema can be retrieved at the url <http://www.ffmpeg.org/schema/ffprobe.xsd>, which redirects to the latest schema committed into the FFmpeg development source code tree.
Note that the output issued will be compliant to the ffprobe.xsd schema only when no special global output options (unit, prefix, byte_binary_prefix, sexagesimal etc.) are specified.
The description of the accepted options follows.
fully_qualified,qโ if set to1specify if the output should be fully qualified. Default value is0. This is required for generating an XML file which can be validated through an XSD file.xsd_strict,xโ if set to1perform more checks for ensuring that the output is XSD compliant. Default value is0. This option automatically setsfully_qualifiedto1.
For more information about the XML format, see <https://www.w3.org/XML/>.
โฑ๏ธ TIMECODE โฑ๏ธ
ffprobe supports Timecode extraction:
- MPEG1/2 timecode is extracted from the GOP, and is available in the video stream details (
-show_streams, seetimecode). - MOV timecode is extracted from
tmcdtrack, so is available in thetmcdstream metadata (-show_streams, seeTAG:timecode). - DV, GXF and AVI timecodes are available in format metadata (
-show_format, seeTAG:timecode).
๐ SYNTAX ๐
This section documents the syntax and formats employed by the FFmpeg libraries and tools.
๐ธ Quoting and escaping ๐ธ
FFmpeg adopts the following quoting and escaping mechanism, unless explicitly specified. The following rules are applied:
'and\are special characters (respectively used for quoting and escaping). In addition to them, there might be other special characters depending on the specific syntax where the escaping and quoting are employed.- A special character is escaped by prefixing it with a
\. - All characters enclosed between
''are included literally in the parsed string. The quote character'itself cannot be quoted, so you may need to close the quote and escape it. - Leading and trailing whitespaces, unless escaped or quoted, are removed from the parsed string.
Note that you may need to add a second level of escaping when using the command line or a script, which depends on the syntax of the adopted shell language.
The function av_get_token defined in libavutil/avstring.h can be used to parse a token quoted or escaped according to the rules defined above.
The tool tools/ffescape in the FFmpeg source tree can be used to automatically quote or escape a string in a script.
๐ Examples ๐
- Escape the string "Crime d'Amour" containing the
'special character:
Crime d\'Amour
- The string above contains a quote, so the
'needs to be escaped when quoting it:
'Crime d'\''Amour'
- Include leading or trailing whitespaces using quoting:
' this string starts and ends with whitespaces '
- Escaping and quoting can be mixed together:
' The string '\'string\'' is a string '
- To include a literal
\you can use either escaping or quoting:
'c:\foo' can be written as c:\\foo
๐ Date ๐
The accepted syntax is:
[(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...]]])|(HHMMSS[.m...]]]))[Z]
now
If the value is now it takes the current time.
Time is local time unless Z is appended, in which case it is interpreted as UTC. If the year-month-day part is not specified it takes the current year-month-day.
๐ Time duration ๐
There are two accepted syntaxes for expressing time duration.
[-][<HH>:]<MM>:<SS>[.<m>...]
HH expresses the number of hours, MM the number of minutes for a maximum of 2 digits, and SS the number of seconds for a maximum of 2 digits. The m at the end expresses decimal value for SS.
or
[-]<S>+[.<m>...][s|ms|us]
S expresses the number of seconds, with the optional decimal part m. The optional literal suffixes s, ms or us indicate to interpret the value as seconds, milliseconds or microseconds, respectively.
In both expressions, the optional - indicates negative duration.
๐ Examples ๐
The following examples are all valid time duration:
55โ 55 seconds0.2โ 0.2 seconds200msโ 200 milliseconds, that's 0.2s200000usโ 200000 microseconds, that's 0.2s12:03:45โ 12 hours, 03 minutes and 45 seconds23.189โ 23.189 seconds
๐ฆ Video size ๐ฆ
Specify the size of the sourced video, it may be a string of the form widthxheight, or the name of a size abbreviation.
The following abbreviations are recognized:
ntscโ720x480palโ720x576qntscโ352x240qpalโ352x288sntscโ640x480spalโ768x576filmโ352x240ntsc-filmโ352x240sqcifโ128x96qcifโ176x144cifโ352x2884cifโ704x57616cifโ1408x1152qqvgaโ160x120qvgaโ320x240vgaโ640x480svgaโ800x600xgaโ1024x768uxgaโ1600x1200qxgaโ2048x1536sxgaโ1280x1024qsxgaโ2560x2048hsxgaโ5120x4096wvgaโ852x480wxgaโ1366x768wsxgaโ1600x1024wuxgaโ1920x1200woxgaโ2560x1600wqsxgaโ3200x2048wquxgaโ3840x2400whsxgaโ6400x4096whuxgaโ7680x4800cgaโ320x200egaโ640x350hd480โ852x480hd720โ1280x720hd1080โ1920x10802kโ2048x10802kflatโ1998x10802kscopeโ2048x8584kโ4096x21604kflatโ3996x21604kscopeโ4096x1716nhdโ640x360hqvgaโ240x160wqvgaโ400x240fwqvgaโ432x240hvgaโ480x320qhdโ960x5402kdciโ2048x10804kdciโ4096x2160uhd2160โ3840x2160uhd4320โ7680x4320
๐ Video rate ๐
Okay so this one sets the frame rate of a video, aka how many frames get generated per second. It has to be a string in the format frame_rate_num/frame_rate_den, an integer number, a float number, or a valid video frame rate abbreviation. slay.
The following abbreviations are recognized:
ntscโ30000/1001palโ25/1qntscโ30000/1001qpalโ25/1sntscโ30000/1001spalโ25/1filmโ24/1ntsc-filmโ24000/1001
๐ Ratio ๐
A ratio can be expressed as an expression, or in the form numerator:denominator.
โ ๏ธ heads up bestie: a ratio with infinite (1/0) or negative value is considered valid, so you should check on the returned value if you want to exclude those values. like, actually check it.
The undefined value can be expressed using the "0:0" string.
๐ Color ๐
It can be the name of a color as defined below (case insensitive match) or a [0x|#]RRGGBB[AA] sequence, possibly followed by @ and a string representing the alpha component.
The alpha component may be a string composed by 0x followed by an hexadecimal number or a decimal number between 0.0 and 1.0, which represents the opacity value (0x00 or 0.0 means completely transparent, 0xff or 1.0 completely opaque). If the alpha component is not specified then 0xff is assumed. cute.
The string random will result in a random color. chaotic icon behavior, honestly.
The following names of colors are recognized:
AliceBlueโ0xF0F8FFAntiqueWhiteโ0xFAEBD7Aquaโ0x00FFFFAquamarineโ0x7FFFD4Azureโ0xF0FFFFBeigeโ0xF5F5DCBisqueโ0xFFE4C4Blackโ0x000000BlanchedAlmondโ0xFFEBCDBlueโ0x0000FFBlueVioletโ0x8A2BE2Brownโ0xA52A2ABurlyWoodโ0xDEB887CadetBlueโ0x5F9EA0Chartreuseโ0x7FFF00Chocolateโ0xD2691ECoralโ0xFF7F50CornflowerBlueโ0x6495EDCornsilkโ0xFFF8DCCrimsonโ0xDC143CCyanโ0x00FFFFDarkBlueโ0x00008BDarkCyanโ0x008B8BDarkGoldenRodโ0xB8860BDarkGrayโ0xA9A9A9DarkGreenโ0x006400DarkKhakiโ0xBDB76BDarkMagentaโ0x8B008BDarkOliveGreenโ0x556B2FDarkorangeโ0xFF8C00DarkOrchidโ0x9932CCDarkRedโ0x8B0000DarkSalmonโ0xE9967ADarkSeaGreenโ0x8FBC8FDarkSlateBlueโ0x483D8BDarkSlateGrayโ0x2F4F4FDarkTurquoiseโ0x00CED1DarkVioletโ0x9400D3DeepPinkโ0xFF1493DeepSkyBlueโ0x00BFFFDimGrayโ0x696969DodgerBlueโ0x1E90FFFireBrickโ0xB22222FloralWhiteโ0xFFFAF0ForestGreenโ0x228B22Fuchsiaโ0xFF00FFGainsboroโ0xDCDCDCGhostWhiteโ0xF8F8FFGoldโ0xFFD700GoldenRodโ0xDAA520Grayโ0x808080Greenโ0x008000GreenYellowโ0xADFF2FHoneyDewโ0xF0FFF0HotPinkโ0xFF69B4IndianRedโ0xCD5C5CIndigoโ0x4B0082Ivoryโ0xFFFFF0Khakiโ0xF0E68CLavenderโ0xE6E6FALavenderBlushโ0xFFF0F5LawnGreenโ0x7CFC00LemonChiffonโ0xFFFACDLightBlueโ0xADD8E6LightCoralโ0xF08080LightCyanโ0xE0FFFFLightGoldenRodYellowโ0xFAFAD2LightGreenโ0x90EE90LightGreyโ0xD3D3D3LightPinkโ0xFFB6C1LightSalmonโ0xFFA07ALightSeaGreenโ0x20B2AALightSkyBlueโ0x87CEFALightSlateGrayโ0x778899LightSteelBlueโ0xB0C4DELightYellowโ0xFFFFE0Limeโ0x00FF00LimeGreenโ0x32CD32Linenโ0xFAF0E6Magentaโ0xFF00FFMaroonโ0x800000MediumAquaMarineโ0x66CDAAMediumBlueโ0x0000CDMediumOrchidโ0xBA55D3MediumPurpleโ0x9370D8MediumSeaGreenโ0x3CB371MediumSlateBlueโ0x7B68EEMediumSpringGreenโ0x00FA9AMediumTurquoiseโ0x48D1CCMediumVioletRedโ0xC71585MidnightBlueโ0x191970MintCreamโ0xF5FFFAMistyRoseโ0xFFE4E1Moccasinโ0xFFE4B5NavajoWhiteโ0xFFDEADNavyโ0x000080OldLaceโ0xFDF5E6Oliveโ0x808000OliveDrabโ0x6B8E23Orangeโ0xFFA500OrangeRedโ0xFF4500Orchidโ0xDA70D6PaleGoldenRodโ0xEEE8AAPaleGreenโ0x98FB98PaleTurquoiseโ0xAFEEEEPaleVioletRedโ0xD87093PapayaWhipโ0xFFEFD5PeachPuffโ0xFFDAB9Peruโ0xCD853FPinkโ0xFFC0CBPlumโ0xDDA0DDPowderBlueโ0xB0E0E6Purpleโ0x800080Redโ0xFF0000RosyBrownโ0xBC8F8FRoyalBlueโ0x4169E1SaddleBrownโ0x8B4513Salmonโ0xFA8072SandyBrownโ0xF4A460SeaGreenโ0x2E8B57SeaShellโ0xFFF5EESiennaโ0xA0522DSilverโ0xC0C0C0SkyBlueโ0x87CEEBSlateBlueโ0x6A5ACDSlateGrayโ0x708090Snowโ0xFFFAFASpringGreenโ0x00FF7FSteelBlueโ0x4682B4Tanโ0xD2B48CTealโ0x008080Thistleโ0xD8BFD8Tomatoโ0xFF6347Turquoiseโ0x40E0D0Violetโ0xEE82EEWheatโ0xF5DEB3Whiteโ0xFFFFFFWhiteSmokeโ0xF5F5F5Yellowโ0xFFFF00YellowGreenโ0x9ACD32
๐ฆ Channel Layout ๐ฆ
A channel layout specifies the spatial disposition of the channels in a multi-channel audio stream. To specify a channel layout, FFmpeg makes use of a special syntax. iykyk, it's giving spatial audio realness.
Individual channels are identified by an id, as given by the table below:
FLโ front leftFRโ front rightFCโ front centerLFEโ low frequencyBLโ back leftBRโ back rightFLCโ front left-of-centerFRCโ front right-of-centerBCโ back centerSLโ side leftSRโ side rightTCโ top centerTFLโ top front leftTFCโ top front centerTFRโ top front rightTBLโ top back leftTBCโ top back centerTBRโ top back rightDLโ downmix leftDRโ downmix rightWLโ wide leftWRโ wide rightSDLโ surround direct leftSDRโ surround direct rightLFE2โ low frequency 2
Standard channel layout compositions can be specified by using the following identifiers:
monoโFCstereoโFL+FR2.1โFL+FR+LFE3.0โFL+FR+FC3.0(back)โFL+FR+BC4.0โFL+FR+FC+BCquadโFL+FR+BL+BRquad(side)โFL+FR+SL+SR3.1โFL+FR+FC+LFE5.0โFL+FR+FC+BL+BR5.0(side)โFL+FR+FC+SL+SR4.1โFL+FR+FC+LFE+BC5.1โFL+FR+FC+LFE+BL+BR5.1(side)โFL+FR+FC+LFE+SL+SR6.0โFL+FR+FC+BC+SL+SR6.0(front)โFL+FR+FLC+FRC+SL+SR3.1.2โFL+FR+FC+LFE+TFL+TFRhexagonalโFL+FR+FC+BL+BR+BC6.1โFL+FR+FC+LFE+BC+SL+SR6.1โFL+FR+FC+LFE+BL+BR+BC6.1(front)โFL+FR+LFE+FLC+FRC+SL+SR7.0โFL+FR+FC+BL+BR+SL+SR7.0(front)โFL+FR+FC+FLC+FRC+SL+SR7.1โFL+FR+FC+LFE+BL+BR+SL+SR7.1(wide)โFL+FR+FC+LFE+BL+BR+FLC+FRC7.1(wide-side)โFL+FR+FC+LFE+FLC+FRC+SL+SR5.1.2โFL+FR+FC+LFE+BL+BR+TFL+TFRoctagonalโFL+FR+FC+BL+BR+BC+SL+SRcubeโFL+FR+BL+BR+TFL+TFR+TBL+TBR5.1.4โFL+FR+FC+LFE+BL+BR+TFL+TFR+TBL+TBR7.1.2โFL+FR+FC+LFE+BL+BR+SL+SR+TFL+TFR7.1.4โFL+FR+FC+LFE+BL+BR+SL+SR+TFL+TFR+TBL+TBR7.2.3โFL+FR+FC+LFE+BL+BR+SL+SR+TFL+TFR+TBC+LFE29.1.4โFL+FR+FC+LFE+BL+BR+FLC+FRC+SL+SR+TFL+TFR+TBL+TBR9.1.6โFL+FR+FC+LFE+BL+BR+FLC+FRC+SL+SR+TFL+TFR+TBL+TBR+TSL+TSRhexadecagonalโFL+FR+FC+BL+BR+BC+SL+SR+WL+WR+TBL+TBR+TBC+TFC+TFL+TFRbinauralโBIL+BIRdownmixโDL+DR22.2โFL+FR+FC+LFE+BL+BR+FLC+FRC+BC+SL+SR+TC+TFL+TFC+TFR+TBL+TBC+TBR+LFE2+TSL+TSR+BFC+BFL+BFR
A custom channel layout can be specified as a sequence of terms, separated by +. Each term can be:
- the name of a single channel (e.g.
FL,FR,FC,LFE, etc.), each optionally containing a custom name after a'@', (e.g.FL@Left,FR@Right,FC@Center,LFE@Low_Frequency, etc.)
A standard channel layout can be specified by the following:
- the name of a single channel (e.g.
FL,FR,FC,LFE, etc.) - the name of a standard channel layout (e.g.
mono,stereo,4.0,quad,5.0, etc.) - a number of channels, in decimal, followed by
c, which gives you the default channel layout for that number of channels (peep the functionav_channel_layout_default). Heads up tho: not every channel count has a default layout, so don't come crying to me if it's not there ๐- a number of channels, in decimal, followed by
C, which gives you an unknown channel layout with that many channels specified. Fair warning bestie: not all channel layout specification strings support unknown channel layouts, so lower your expectations accordingly ๐ - a channel layout mask, in hexadecimal starting with
0x(see theAV_CH_*macros inlibavutil/channel_layout.h.
- a number of channels, in decimal, followed by
Before libavutil version 53 the trailing c used to specify a number of channels was optional, but now it is required โ glow-up era, no shortcuts โ while a channel layout mask can also be specified as a decimal number (if and only if it's not followed by c or C).
Also go look at the function av_channel_layout_from_string defined in libavutil/channel_layout.h. It's giving reference material โจ
๐ธ EXPRESSION EVALUATION ๐ธ
When evaluating an arithmetic expression, FFmpeg uses an internal formula evaluator, implemented through the libavutil/eval.h interface. Lowkey iconic infrastructure ngl.
An expression may contain unary operators, binary operators, constants, and functions. All the good stuff ๐
Two expressions expr1 and expr2 can be combined to form another expression expr1;expr2. Both expr1 and expr2 are evaluated in turn, and the new expression evaluates to the value of expr2. It's giving "second one ate, honestly" ๐
The following binary operators are available: +, -, *, /, ^.
The following unary operators are available: +, -.
Some internal variables can be used to store and load intermediary results. You access them using the ld and st functions with an index argument that ranges from 0 to 9, specifying which internal variable you're grabbing. Little numbered lockers, very demure ๐
The following functions are available โ buckle up, this is a long list and every single one matters:
abs(x)โ Compute absolute value of x.acos(x)โ Compute arccosine of x.asin(x)โ Compute arcsine of x.atan(x)โ Compute arctangent of x.atan2(y, x)โ Compute principal value of the arc tangent of y/x.between(x, min, max)โ Return1if x is greater than or equal to min and lesser than or equal to max,0otherwise.bitand(x, y),bitor(x, y)โ Compute bitwise and/or operation on x and y.
The results of the evaluation of x and y are converted to integers before executing the bitwise operation.
Note that both the conversion to integer and the conversion back to floating point can lose precision. Beware of unexpected results for large numbers (usually 2^53 and larger). ๐ fr fr, do not trust the big numbers
ceil(expr)โ Round the value of expression expr upwards to the nearest integer. For example,ceil(1.5)is2.0.clip(x, min, max)โ Return the value of x clipped between min and max.cos(x)โ Compute cosine of x.cosh(x)โ Compute hyperbolic cosine of x.eq(x, y)โ Return1if x and y are equivalent,0otherwise.exp(x)โ Compute exponential of x (with basee, the Euler's number).floor(expr)โ Round the value of expression expr downwards to the nearest integer. For example,floor(-1.5)is-2.0.gauss(x)โ Compute Gauss function of x, corresponding toexp(-x*x/2) / sqrt(2*PI).gcd(x, y)โ Return the greatest common divisor of x and y. If both x and y are0or either or both are less than zero then behavior is undefined. Undefined behaviour era, tread carefully ๐ซถgt(x, y)โ Return1if x is greater than y,0otherwise.gte(x, y)โ Return1if x is greater than or equal to y,0otherwise.hypot(x, y)โ This function is similar to the C function with the same name; it returnssqrt(x*x + y*y), the length of the hypotenuse of a right triangle with sides of length x and y, or the distance of the point (x, y) from the origin. Geometry class flashback ๐ญif(x, y)โ Evaluate x, and if the result is non-zero return the result of the evaluation of y, return0otherwise.if(x, y, z)โ Evaluate x, and if the result is non-zero return the evaluation result of y, otherwise the evaluation result of z.ifnot(x, y)โ Evaluate x, and if the result is zero return the result of the evaluation of y, return0otherwise.ifnot(x, y, z)โ Evaluate x, and if the result is zero return the evaluation result of y, otherwise the evaluation result of z.isinf(x)โ Return1.0if x is+/-INFINITY,0.0otherwise.isnan(x)โ Return1.0if x isNAN,0.0otherwise.ld(idx)โ Load the value of the internal variable with index idx, which was previously stored withst(idx, expr). The function returns the loaded value. โจ the retrieve half of the equationlerp(x, y, z)โ Return linear interpolation between x and y by amount of z.log(x)โ Compute natural logarithm of x.lt(x, y)โ Return1if x is lesser than y,0otherwise.lte(x, y)โ Return1if x is lesser than or equal to y,0otherwise.max(x, y)โ Return the maximum between x and y.min(x, y)โ Return the minimum between x and y.mod(x, y)โ Compute the remainder of division of x by y.not(expr)โ Return1.0if expr is zero,0.0otherwise.pow(x, y)โ Compute the power of x elevated y, it is equivalent to(x)^(y).print(t),print(t, l)โ Print the value of expression t with loglevel l. If l is not specified then a default log level is used. Return the value of the expression printed. Yes it prints AND returns, multitasking queen ๐random(idx)โ Return a pseudo random value between0.0and1.0. idx is the index of the internal variable used to save the seed/state, which can be previously stored withst(idx).
To initialize the seed, you need to store the seed value as a 64-bit unsigned integer in the internal variable with index idx.
For example, to store the seed with value 42 in the internal variable with index 0 and print a few random values:
st(0,42); print(random(0)); print(random(0)); print(random(0))
randomi(idx, min, max)โ Return a pseudo random value in the interval between min and max. idx is the index of the internal variable which will be used to save the seed/state, which can be previously stored withst(idx).
To initialize the seed, you need to store the seed value as a 64-bit unsigned integer in the internal variable with index idx.
root(expr, max)โ Find an input value for which the function represented by expr with argumentld(0)is0in the interval0..max.
The expression in expr must denote a continuous function or the result is undefined. No cap, don't play with this one ๐
ld(0) is used to represent the function input value, which means that the given expression will be evaluated multiple times with various input values that the expression can access through ld(0). When the expression evaluates to 0 then the corresponding input value will be returned.
round(expr)โ Round the value of expression expr to the nearest integer. For example,round(1.5)is2.0.sgn(x)โ Compute sign of x.sin(x)โ Compute sine of x.sinh(x)โ Compute hyperbolic sine of x.sqrt(expr)โ Compute the square root of expr. This is equivalent to(expr)^.5.squish(x)โ Compute expression1/(1 + exp(4*x)).st(idx, expr)โ Store the value of the expression expr in an internal variable. idx specifies the index of the variable where to store the value, and it is a value ranging from0to9. The function returns the value stored in the internal variable.
The stored value can be retrieved with ld(var).
Note: variables are currently not shared between expressions. Sad but true ๐
tan(x)โ Compute tangent of x.tanh(x)โ Compute hyperbolic tangent of x.taylor(expr, x),taylor(expr, x, idx)โ Evaluate a Taylor series at x, given an expression representing theld(idx)-th derivative of a function at0.
When the series does not converge the result is undefined. Convergence is not optional bestie ๐ค
ld(idx) is used to represent the derivative order in expr, which means that the given expression will be evaluated multiple times with various input values that the expression can access through ld(idx). If idx is not specified then 0 is assumed.
Note, when you have the derivatives at y instead of 0, taylor(expr, x-y) can be used. Little trick, very cunty of the math ๐
time(0)โ Return the current (wallclock) time in seconds.trunc(expr)โ Round the value of expression expr towards zero to the nearest integer. For example,trunc(-1.5)is-1.0.while(cond, expr)โ Evaluate expression expr while the expression cond is non-zero, and returns the value of the last expr evaluation, orNANif cond was always false.
The following constants are available:
PIโ area of the unit disc, approximately3.14Eโexp(1)(Euler's number), approximately2.718PHIโ golden ratio(1+sqrt(5))/2, approximately1.618
Assuming that an expression is considered "true" if it has a non-zero value, note that:
*works like AND+works like OR
For example the construct:
if (A AND B) then C
is equivalent to:
if(A*B, C)
In your C code, you can extend the list of unary and binary functions, and define recognized constants, so that they are available for your expressions. Go build ur own little ecosystem ๐
The evaluator also recognizes the International System unit prefixes. If i is appended after the prefix, binary prefixes are used, which are based on powers of 1024 instead of powers of 1000. The B postfix multiplies the value by 8, and can be appended after a unit prefix or used alone. This allows using for example KB, MiB, G and B as number postfix. Slay, suffix literacy ๐
The list of available International System prefixes follows, with indication of the corresponding powers of 10 and of 2:
yโ10^-24/2^-80zโ10^-21/2^-70aโ10^-18/2^-60fโ10^-15/2^-50pโ10^-12/2^-40nโ10^-9/2^-30uโ10^-6/2^-20mโ10^-3/2^-10cโ10^-2dโ10^-1hโ10^2kโ10^3/2^10Kโ10^3/2^10Mโ10^6/2^20Gโ10^9/2^30Tโ10^12/2^40Pโ10^15/2^50Eโ10^18/2^60Zโ10^21/2^70Yโ10^24/2^80
๐ CODEC OPTIONS ๐
libavcodec provides some generic global options, which can be set on all the encoders and decoders. In addition, each codec may support so-called private options, which are specific for a given codec. Main character options, honestly ๐
Sometimes, a global option may only affect a specific kind of codec, and may be nonsensical or ignored by another, so you need to be aware of the meaning of the specified options. Don't just yeet flags around and hope for the best ๐ญ
Also some options are meant only for decoding or encoding. Read the room, basically ๐
okay so real talk, bestie: you can set these options by specifying -option value in the FFmpeg tools, or by setting the value explicitly in the AVCodecContext options, or by using the libavutil/opt.h API for programmatic use. ๐
the full list of supported options follows โ and yes, we're doing all of them.
bโinteger(encoding,audio,video): set bitrate in bits/s. Default value is200K.abโinteger(encoding,audio): set audio bitrate (in bits/s). Default value is128K.btโinteger(encoding,video): set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate tolerance specifies how far ratecontrol is willing to deviate from the target average bitrate value. This is not related to min/max bitrate. Lowering tolerance too much has an adverse effect on quality.flagsโflags(decoding/encoding,audio,video,subtitles): set generic flags.
Possible values:
mv4โ use four motion vector by macroblock (mpeg4).qpelโ use 1/4 pel motion compensation.loopโ use loop filter.qscaleโ use fixed qscale.pass1โ use internal 2pass ratecontrol in first pass mode.pass2โ use internal 2pass ratecontrol in second pass mode.grayโ only decode/encode grayscale.psnrโ seterror[?]variables during encoding.truncatedโ input bitstream might be randomly truncated.drop_changedโ don't output frames whose parameters differ from first decoded frame in stream. ErrorAVERROR_INPUT_CHANGEDis returned when a frame is dropped.ildctโ use interlaced DCT.low_delayโ force low delay.global_headerโ place global headers in extradata instead of every keyframe.bitexactโ only write platform-, build- and time-independent data. (except(I)DCT). This ensures that file and data checksums are reproducible and match between platforms. Its primary use is for regression testing.aicโ apply H263 advanced intra coding / mpeg4 ac prediction.ilmeโ apply interlaced motion estimation.cgopโ use closed gop.output_corruptโ output even potentially corrupted frames.
time_baseโrational number: set codec time base. It is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented. For fixed-fps content, timebase should be1 / frame_rateand timestamp increments should be identically1.gโinteger(encoding,video): set the group of picture (GOP) size. Default value is12.arโinteger(decoding/encoding,audio): set audio sampling rate (in Hz).acโinteger(decoding/encoding,audio): set number of audio channels.cutoffโinteger(encoding,audio): set cutoff bandwidth. (Supported only by selected encoders, see their respective documentation sections.)frame_sizeโinteger(encoding,audio): set audio frame size. Each submitted frame except the last must contain exactlyframe_sizesamples per channel. May be0when the codec hasCODEC_CAP_VARIABLE_FRAME_SIZEset, in that case the frame size is not restricted. It is set by some decoders to indicate constant frame size.frame_numberโinteger: set the frame number.delayโinteger.qcompโfloat(encoding,video): set video quantizer scale compression (VBR). It is used as a constant in the ratecontrol equation. Recommended range for defaultrc_eq:0.0-1.0.qblurโfloat(encoding,video): set video quantizer scale blur (VBR).qminโinteger(encoding,video): set min video quantizer scale (VBR). Must be included between-1and69, default value is2.qmaxโinteger(encoding,video): set max video quantizer scale (VBR). Must be included between-1and1024, default value is31.qdiffโinteger(encoding,video): set max difference between the quantizer scale (VBR).bfโinteger(encoding,video): set max number of B frames between non-B-frames. Must be an integer between-1and16.0means that B-frames are disabled. If a value of-1is used, it will choose an automatic value depending on the encoder. Default value is0.b_qfactorโfloat(encoding,video): set qp factor between P and B frames.codec_tagโinteger.bugโflags(decoding,video): workaround not auto detected encoder bugs.
Possible values:
autodetectxvid_ilaceโ Xvid interlacing bug (autodetected iffourcc==XVIX)ump4โ (autodetected iffourcc==UMP4)no_paddingโ padding bug (autodetected)amvqpel_chromastd_qpelโ old standard qpel (autodetected per fourcc/version)qpel_chroma2direct_blocksizeโ direct-qpel-blocksize bug (autodetected per fourcc/version)edgeโ edge padding bug (autodetected per fourcc/version)hpel_chromadc_clipmsโ workaround various bugs in microsoft broken decoders.truncโ trancated frames
strictโinteger(decoding/encoding,audio,video): specify how strictly to follow the standards.
Possible values:
veryโ strictly conform to an older more strict version of the spec or reference softwarestrictโ strictly conform to all the things in the spec no matter what consequencesnormalunofficialโ allow unofficial extensionsexperimentalโ allow non standardized experimental things, experimental (unfinished/work in progress/not well tested) decoders and encoders. Note: experimental decoders can pose a security risk, do not use this for decoding untrusted input.
b_qoffsetโfloat(encoding,video): set QP offset between P and B frames.err_detectโflags(decoding,audio,video): set error detection flags.
Possible values:
crccheckโ verify embedded CRCsbitstreamโ detect bitstream specification deviationsbufferโ detect improper bitstream lengthexplodeโ abort decoding on minor error detectionignore_errโ ignore decoding errors, and continue decoding. This is useful if you want to analyze the content of a video and thus want everything to be decoded no matter what. This option will not result in a video that is pleasing to watch in case of errors.carefulโ consider things that violate the spec and have not been seen in the wild as errorscompliantโ consider all spec non compliancies as errorsaggressiveโ consider things that a sane encoder should not do as an error
has_b_framesโinteger.block_alignโinteger.rc_override_countโinteger.maxrateโinteger(encoding,audio,video): set max bitrate tolerance (in bits/s). Requiresbufsizeto be set.minrateโinteger(encoding,audio,video): set min bitrate tolerance (in bits/s). Most useful in setting up a CBR encode. It is of little use elsewise.bufsizeโinteger(encoding,audio,video): set ratecontrol buffer size (in bits).i_qfactorโfloat(encoding,video): set QP factor between P and I frames.i_qoffsetโfloat(encoding,video): set QP offset between P and I frames.dctโinteger(encoding,video): set DCT algorithm.
Possible values:
autoโ autoselect a good one (default)fastintโ fast integerintโ accurate integermmxaltivecfaanโ floating point AAN DCT
lumi_maskโfloat(encoding,video): compress bright areas stronger than medium ones.tcplx_maskโfloat(encoding,video): set temporal complexity masking.scplx_maskโfloat(encoding,video): set spatial complexity masking.p_maskโfloat(encoding,video): set inter masking.dark_maskโfloat(encoding,video): compress dark areas stronger than medium ones.idctโinteger(decoding/encoding,video): select IDCT implementation.
Possible values:
autointsimplesimplemmxsimpleautoโ automatically pick a IDCT compatible with the simple onearmaltivecsh4simplearmsimplearmv5tesimplearmv6simpleneonxvidfaaniโ floating point AAN IDCT
slice_countโinteger.ecโflags(decoding,video): set error concealment strategy.
Possible values:
guess_mvsโ iterative motion vector (MV) search (slow)deblockโ use strong deblock filter for damaged MBsfavor_interโ favor predicting from the previous frame instead of the current
bits_per_coded_sampleโinteger.aspectโrational number(encoding,video): set sample aspect ratio.sarโrational number(encoding,video): set sample aspect ratio. Alias toaspect.debugโflags(decoding/encoding,audio,video,subtitles): print specific debug info.
Possible values:
pictโ picture inforcโ rate controlbitstreammb_typeโ macroblock (MB) typeqpโ per-block quantization parameter (QP)dct_coeffgreen_metadataโ display complexity metadata for the upcoming frame, GoP or for a given duration.skipstartcodeerโ error recognitionmmcoโ memory management control operations (H.264)bugsbuffersโ picture buffer allocationsthread_opsโ threading operationsnomcโ skip motion compensation
cmpโinteger(encoding,video): set full pel me compare function.
Possible values:
sadโ sum of absolute differences, fast (default)sseโ sum of squared errorssatdโ sum of absolute Hadamard transformed differencesdctโ sum of absolute DCT transformed differencespsnrโ sum of squared quantization errors (avoid, low quality)bitโ number of bits needed for the blockrdโ rate distortion optimal, slowzeroโ0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snoww97โ 9/7 wavelet, only used in snowdctmaxchroma
subcmpinteger (encoding,video) โ sets the sub pel me compare function. bestie you get to pick the whole vibe of how it compares:
Possible values:
sadโ sum of absolute differences, fast (default)sseโ sum of squared errorssatdโ sum of absolute Hadamard transformed differencesdctโ sum of absolute DCT transformed differencespsnrโ sum of squared quantization errors (avoid, low quality)bitโ number of bits needed for the blockrdโ rate distortion optimal, slowzeroโ 0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snoww97โ 9/7 wavelet, only used in snowdctmaxchroma
mbcmpinteger (encoding,video) โ sets the macroblock compare function, same little menu of options as above:
Possible values:
sadโ sum of absolute differences, fast (default)sseโ sum of squared errorssatdโ sum of absolute Hadamard transformed differencesdctโ sum of absolute DCT transformed differencespsnrโ sum of squared quantization errors (avoid, low quality)bitโ number of bits needed for the blockrdโ rate distortion optimal, slowzeroโ 0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snoww97โ 9/7 wavelet, only used in snowdctmaxchroma
ildctcmpinteger (encoding,video) โ sets the interlaced dct compare function. yep, same value list, third time's the charm ๐
Possible values:
sadโ sum of absolute differences, fast (default)sseโ sum of squared errorssatdโ sum of absolute Hadamard transformed differencesdctโ sum of absolute DCT transformed differencespsnrโ sum of squared quantization errors (avoid, low quality)bitโ number of bits needed for the blockrdโ rate distortion optimal, slowzeroโ 0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snoww97โ 9/7 wavelet, only used in snowdctmaxchroma
dia_sizeinteger (encoding,video) โ sets the diamond type & size for motion estimation. it's giving โจshapesโจ, pick your fighter:(1024, INT_MAX)โ full motion estimation(slowest)(768, 1024]โ umh motion estimation(512, 768]โ hex motion estimation(256, 512]โ l2s diamond motion estimation[2,256]โ var diamond motion estimation(-1, 2)โ small diamond motion estimation-1โ funny diamond motion estimation(INT_MIN, -1)โ sab diamond motion estimation
last_predinteger (encoding,video) โ sets how many motion predictors carry over from the previous frame. lowkey nostalgic ๐ฅฒprecmpinteger (encoding,video) โ sets the pre motion estimation compare function. yes it's the same iconic menu again:
Possible values:
sadโ sum of absolute differences, fast (default)sseโ sum of squared errorssatdโ sum of absolute Hadamard transformed differencesdctโ sum of absolute DCT transformed differencespsnrโ sum of squared quantization errors (avoid, low quality)bitโ number of bits needed for the blockrdโ rate distortion optimal, slowzeroโ 0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snoww97โ 9/7 wavelet, only used in snowdctmaxchroma
pre_dia_sizeinteger (encoding,video) โ sets the diamond type & size for the motion estimation pre-pass. like a little warm-up round ๐subqinteger (encoding,video) โ sets the sub pel motion estimation quality.me_rangeinteger (encoding,video) โ sets the limit for the motion vectors range (1023for DivX player). fyi the DivX player is out here with opinions.global_qualityinteger (encoding,audio,video) โ no extra notes, it's just vibes and a number โจslice_flagsinteger โ same, just the flag, nothing more to say ๐ซถmbdinteger (encoding,video) โ sets the macroblock decision algorithm (high quality mode). choose your destiny:
Possible values:
simpleโ usembcmp(default)bitsโ use fewest bitsrdโ use best rate distortion
rc_init_occupancyinteger (encoding,video) โ sets how many bits should already be loaded into the rc buffer before decoding even starts. pre-gaming the buffer, we love to see it ๐flags2flags (decoding/encoding,audio,video,subtitles) โ the big flag bag. Possible values:fastโ allow non spec compliant speedup tricks.nooutโ skip bitstream encoding.ignorecropโ ignore cropping information from sps.local_headerโ place global headers at every keyframe instead of in extradata.chunksโ frame data might be split into multiple chunks.showallโ show all frames before the first keyframe.export_mvsโ export motion vectors into frame side-data (see"AV_FRAME_DATA_MOTION_VECTORS") for codecs that support it. See alsodoc/examples/export_mvs.c.skip_manualโ do not skip samples and export skip information as frame side data.ass_ro_flush_noopโ do not reset ASS ReadOrder field on flush.icc_profilesโ generate/parse embedded ICC profiles from/to colorimetry tags.
export_side_dataflags (decoding/encoding,audio,video,subtitles) โ what extra little goodies go out as side-data. Possible values:mvsโ export motion vectors into frame side-data (see"AV_FRAME_DATA_MOTION_VECTORS") for codecs that support it. See alsodoc/examples/export_mvs.c.prftโ export encoder Producer Reference Time into packet side-data (see"AV_PKT_DATA_PRFT") for codecs that support it.venc_paramsโ export video encoding parameters through frame side data (see"AV_FRAME_DATA_VIDEO_ENC_PARAMS") for codecs that support it. At present, those are H.264 and VP9.film_grainโ export film grain parameters through frame side data (see"AV_FRAME_DATA_FILM_GRAIN_PARAMS"). Supported at present by AV1 decoders.enhancementsโ export picture enhancement metadata through frame side data, e.g. LCEVC (see"AV_FRAME_DATA_LCEVC").
threadsinteger (decoding/encoding,video) โ sets the number of threads used, in case the codec implementation you picked actually supports multi-threading. more cores more chaos ๐ฅ
Possible values:
auto,0โ automatically select the number of threads to set
Default value is auto.
dcinteger (encoding,video) โ setsintra_dc_precision.nssewinteger (encoding,video) โ sets the nsse weight.skip_topinteger (decoding,video) โ sets how many macroblock rows at the top get skipped. bye top rows ๐skip_bottominteger (decoding,video) โ sets how many macroblock rows at the bottom get skipped. and bye bottom rows ๐profileinteger (encoding,audio,video) โ sets the encoder codec profile. default value is unknown, and encoder specific profiles are documented in the relevant encoder documentation (go read those, bestie).levelinteger (encoding,audio,video) โ sets the encoder level. this level depends on the specific codec and might correspond to the profile level. it's set by default to unknown.
Possible values:
unknown
lowresinteger (decoding,audio,video) โ decode at1= 1/2,2=1/4,3=1/8 resolutions. tiny mode activate ๐mblmininteger (encoding,video) โ sets the min macroblock lagrange factor (VBR).mblmaxinteger (encoding,video) โ sets the max macroblock lagrange factor (VBR).skip_loop_filter,skip_idct,skip_frameinteger (decoding,video) โ these make the decoder straight up discard processing depending on the frame type you select with the option value.
skip_loop_filter skips frame loop filtering, skip_idct skips frame IDCT/dequantization, skip_frame skips decoding entirely.
Possible values:
noneโ discard no frame.defaultโ discard useless frames like 0-sized frames.norefโ discard all non-reference frames.bidirโ discard all bidirectional frames.nokeyโ discard all frames excepts keyframes.nointraโ discard all frames except I frames.allโ discard all frames.
Default value is default.
bidir_refineinteger (encoding,video) โ refines the two motion vectors used in bidirectional macroblocks. two little vectors getting a glow-up โจkeyint_mininteger (encoding,video) โ sets the minimum interval between IDR-frames.refsinteger (encoding,video) โ sets the reference frames to consider for motion compensation.trellisinteger (encoding,audio,video) โ sets rate-distortion optimal quantization.mv0_thresholdinteger (encoding,video) โ no extra notes attached, just the knob ๐๏ธcompression_levelinteger (encoding,audio,video) โ same, it's a level, for compression, iconic.bits_per_raw_sampleinteger โ that's it, that's the option ๐channel_layoutinteger (decoding/encoding,audio) โ see the Channel Layout section in theffmpeg-utils(1)manual for the required syntax. go check the other page, iykyk.rc_max_vbv_usefloat (encoding,video) โ a float, no description, moving on ๐ฆrc_min_vbv_usefloat (encoding,video) โ same deal, float energy.color_primariesinteger (decoding/encoding,video) โ the color primaries menu. Possible values:bt709โ BT.709bt470mโ BT.470 Mbt470bgโ BT.470 BGsmpte170mโ SMPTE 170 Msmpte240mโ SMPTE 240 Mfilmโ Filmbt2020โ BT.2020smpte428,smpte428_1โ SMPTE ST 428-1smpte431โ SMPTE 431-2smpte432โ SMPTE 432-1jedec-p22โ JEDEC P22
color_trcinteger (decoding/encoding,video) โ the transfer characteristics menu, and yes some of these have aliases so you've got options. Possible values:bt709โ BT.709gamma22โ BT.470 Mgamma28โ BT.470 BGsmpte170mโ SMPTE 170 Msmpte240mโ SMPTE 240 Mlinearโ Linearlog,log100โ Loglog_sqrt,log316โ Log square rootiec61966_2_4,iec61966-2-4โ IEC 61966-2-4bt1361,bt1361eโ BT.1361iec61966_2_1,iec61966-2-1โ IEC 61966-2-1bt2020_10,bt2020_10bitโ BT.2020 - 10 bitbt2020_12,bt2020_12bitโ BT.2020 - 12 bit
and the color_trc menu keeps serving these last few icons, no cap:
smpte2084โ SMPTE ST 2084smpte428,smpte428_1โ SMPTE ST 428-1arib-std-b67โ ARIB STD-B67colorspaceinteger (decoding/encoding,video) โ the color space menu is giving full rainbow, bestie. Possible values:rgbโ RGBbt709โ BT.709fccโ FCCbt470bgโ BT.470 BGsmpte170mโ SMPTE 170 Msmpte240mโ SMPTE 240 Mycocgโ YCOCGbt2020nc,bt2020_nclโ BT.2020 NCLbt2020c,bt2020_clโ BT.2020 CLsmpte2085โ SMPTE 2085chroma-derived-ncโ Chroma-derived NCLchroma-derived-cโ Chroma-derived CLictcpโ ICtCp
color_rangeinteger (decoding/encoding,video) โ if you use it as an input parameter, itโs a hint to the decoder about which color_range the input has. Possible values:tv,mpeg,limitedโ MPEG (219*2^(n-8))pc,jpeg,fullโ JPEG (2^n-1)
chroma_sample_locationinteger (decoding/encoding,video) โ possible values areleft,center,topleft,top,bottomleft,bottom.alpha_modeinteger (decoding/encoding,video) โ possible values arepremultipliedandstraight.log_level_offsetinteger โ sets the log level offset.slicesinteger (encoding,video) โ number of slices, used in parallelized encoding.thread_typeflags (decoding/encoding,video) โ pick which multithreading methods to use. Usingframewill increase decoding delay by one frame per thread, so clients that cannot provide future frames should not use it. Possible values:sliceโ decode more than one part of a single frame at once. Multithreading using slices works only when the video was encoded with slices.frameโ decode more than one frame at once.
Default value is slice+frame.
audio_service_typeinteger (encoding,audio) โ sets the audio service type. Possible values:maโ Main Audio Serviceefโ Effectsviโ Visually Impairedhiโ Hearing Impaireddiโ Dialoguecoโ Commentaryemโ Emergencyvoโ Voice Overkaโ Karaoke
request_sample_fmtsample_fmt (decoding,audio) โ sets the sample format audio decoders should prefer. Default value is"none".pkt_timebaserational number โ literally a rational number, iykyk.sub_charencencoding (decoding,subtitles) โ sets the input subtitles character encoding.field_orderfield_order (video) โ sets or overrides the field order of the video. Possible values:progressiveโ progressive videottโ interlaced video, top field coded and displayed firstbbโ interlaced video, bottom field coded and displayed firsttbโ interlaced video, top coded first, bottom displayed firstbtโ interlaced video, bottom coded first, top displayed first
skip_alphabool (decoding,video) โ set to1to disable processing alpha (transparency). This works like thegrayflag in theflagsoption, which skips chroma information instead of alpha. Default is0.codec_whitelistlist (input) โ a","-separated list of allowed decoders. By default all are allowed.dump_separatorstring (input) โ the separator used to separate the fields printed on the command line about Stream parameters. For example, to separate the fields with newlines and indentation:
ffprobe -dump_separator "
" -i ~/videos/matrixbench_mpeg2.mpg
max_pixelsinteger (decoding/encoding,video) โ maximum number of pixels per image. This value can be used to avoid out of memory failures due to large images.apply_croppingbool (decoding,video) โ enables cropping if the cropping parameters are multiples of the required alignment for the left and top parameters. If the alignment is not met, the cropping will be partially applied to maintain alignment. Default is1(enabled).
Note: the required alignment depends on whetherAV_CODEC_FLAG_UNALIGNEDis set and on the CPU.AV_CODEC_FLAG_UNALIGNEDcannot be changed from the command line. Also, hardware decoders will not apply left/top Cropping.
๐ฌ DECODERS ๐ฌ
Decoders are configured elements in FFmpeg that let you decode multimedia streams. Okay so when you configure your FFmpeg build, all the supported native decoders are enabled by default. Decoders that need an external library have to be enabled manually via the corresponding --enable-lib option. You can list all available decoders using the configure option --list-decoders.
You can disable all the decoders with the configure option --disable-decoders and selectively enable / disable single decoders with the options --enable-decoder=DECODER / --disable-decoder=DECODER.
The option -decoders of the ff* tools will display the list of enabled decoders. Slay.
๐ฅ VIDEO DECODERS ๐ฅ
A description of some of the currently available video decoders follows. Buckle up, bestie.
โจ av1 โจ
AOMedia Video 1 (AV1) decoder.
Options
operating_pointโ select an operating point of a scalable AV1 bitstream (0-31). Default is0.
๐ธ hevc ๐ธ
HEVC (AKA ITU-T H.265 or ISO/IEC 23008-2) decoder.
The decoder supports MV-HEVC multiview streams with at most two views. Views to be output are selected by supplying a list of view IDs to the decoder (the view_ids option). This option may be set either statically before decoder init, or from the get_format() callback โ useful for the case when the view count or IDs change dynamically during decoding.
Only the base layer is decoded by default.
Note: if you are using the ffmpeg CLI tool, you should be using view specifiers as documented in its manual, rather than the options documented here.
Options
view_ids(MV-HEVC) โ specify a list of view IDs that should be output. This option can also be set to a single'-1', which will cause all views defined in the VPS to be decoded and output.view_ids_available(MV-HEVC) โ this option may be read by the caller to retrieve an array of view IDs available in the active VPS. The array is empty for single-layer video.
The value of this option is guaranteed to be accurate when read from the get_format() callback. It may also be set at other times (e.g. after opening the decoder), but the value is informational only and may be incorrect (e.g. when the stream contains multiple distinct VPS NALUs).
view_pos_available(MV-HEVC) โ this option may be read by the caller to retrieve an array of view positions (left, right, or unspecified) available in the active VPS, asAVStereo3DViewvalues. When the array is available, its elements apply to the corresponding elements ofview_ids_available, i.e.view_pos_available[i]contains the position of view with IDview_ids_available[i].
Same validity restrictions as for view_ids_available apply to this option.
๐ฆ rawvideo ๐ฆ
Raw video decoder.
This decoder decodes rawvideo streams.
Options
top(top_field_first) โ specify the assumed field type of the input video.-1โ the video is assumed to be progressive (default)0โ bottom-field-first is assumed1โ top-field-first is assumed
๐ libdav1d ๐
dav1d AV1 decoder.
libdav1d allows libavcodec to decode the AOMedia Video 1 (AV1) codec. Requires the presence of the libdav1d headers and library during configuration. You need to explicitly configure the build with --enable-libdav1d.
Options
The following options are supported by the libdav1d wrapper.
max_frame_delayโ set max amount of frames the decoder may buffer internally. The default value is0(autodetect).filmgrainโ apply film grain to the decoded video if present in the bitstream. Defaults to the internal default of the library.
This option is deprecated and will be removed in the future. See the global option export_side_data to export Film Grain parameters instead of applying it.
oppointโ select an operating point of a scalable AV1 bitstream (0-31). Defaults to the internal default of the library.alllayersโ output all spatial layers of a scalable AV1 bitstream. The default value isfalse.
๐ง libdavs2 ๐ง
AVS2-P2/IEEE1857.4 video decoder wrapper.
This decoder allows libavcodec to decode AVS2 streams with the davs2 library.
๐ libuavs3d ๐
AVS3-P2/IEEE1857.10 video decoder.
libuavs3d allows libavcodec to decode AVS3 streams. Requires the presence of the libuavs3d headers and library during configuration. You need to explicitly configure the build with --enable-libuavs3d.
Options
The following option is supported by the libuavs3d wrapper.
frame_threadsโ set amount of frame threads to use during decoding. The default value is0(autodetect).
๐ฅ libxevd ๐ฅ
eXtra-fast Essential Video Decoder (XEVD) MPEG-5 EVC decoder wrapper.
This decoder requires the presence of the libxevd headers and library during configuration. You need to explicitly configure the build with --enable-libxevd.
The xevd project website is at https://github.com/mpeg5/xevd.
Options
The following options are supported by the libxevd wrapper. The xevd-equivalent options or values are listed in parentheses for easy migration.
To get a more accurate and extensive documentation of the libxevd options, invoke the command xevd_app --help or consult the libxevd documentation.
threads(threads) โ force to use a specific number of threads.
๐ QSV Decoders ๐
The family of Intel QuickSync Video decoders (VC1, MPEG-2, H.264, HEVC, JPEG/MJPEG, VP8, VP9, AV1, VVC).
Common Options
The following options are supported by all qsv decoders.
async_depthโ internal parallelization depth. The higher the value, the higher the latency.gpu_copyโ a GPU-accelerated copy between video and system memory. Values:defaultonoff
HEVC Options
Extra options for hevc_qsv.
load_pluginโ a user plugin to load in an internal session. Values:nonehevc_swhevc_hw
load_pluginsโ a:-separatelist of hexadecimal plugin UIDs to load in an internal session.
๐ v210 ๐
Uncompressed 4:2:2 10-bit decoder.
Options
custom_strideโ set the line size of the v210 data in bytes. The default value is0(autodetect). You can use the special-1value for a strideless v210 as seen in BOXX files.
๐ธ AUDIO DECODERS ๐ธ
okay so here's the tea on some of the audio decoders that are available rn ๐
๐ง ac3
the AC-3 audio decoder, periodt.
this decoder implements part of ATSC A/52:2010 and ETSI TS 102 366, plus the undocumented RealAudio 3 (a.k.a. dnet). yes bestie, even the mysterious undocumented stuff ๐
AC-3 Decoder Options
-drc_scalevalue โ the Dynamic Range Scale Factor. it's the factor applied to dynamic range values coming from the AC-3 stream, and it gets applied exponentially โจ the default value is1. there are 3 notable scale factor ranges:drc_scale == 0โ DRC disabled. produces full range audio ๐ถ0 < drc_scale <= 1โ DRC enabled. applies a fraction of the stream DRC value. audio reproduction lands somewhere between full range and full compression ๐ซถdrc_scale > 1โ DRC enabled. appliesdrc_scaleasymmetrically. loud sounds get fully compressed, soft sounds get enhanced ๐
๐ flac
the FLAC audio decoder.
this decoder aims to implement the complete FLAC specification from Xiph, no cap ๐
FLAC Decoder options
-use_buggy_lpcโ okay so the lavc FLAC encoder used to produce buggy streams with high lpc values (like the default value ๐). this option makes it possible to decode such streams correctly by using lavc's old buggy lpc logic for decoding. literally fixing the past with the past.
๐ฆ ffwavesynth
internal wave synthesizer.
this decoder generates wave patterns according to predefined sequences. its use is purely internal and the format of the data it accepts is not publicly documented ๐คซ iykyk
๐ libcelt
libcelt decoder wrapper.
libcelt allows libavcodec to decode the Xiph CELT ultra-low delay audio codec. requires the presence of the libcelt headers and library during configuration. you need to explicitly configure the build with --enable-libcelt โญ
๐ libgsm
libgsm decoder wrapper.
libgsm allows libavcodec to decode the GSM full rate audio codec. requires the presence of the libgsm headers and library during configuration. you need to explicitly configure the build with --enable-libgsm.
this decoder supports both the ordinary GSM and the Microsoft variant ๐ซถ two for the price of one, slay.
๐ธ libilbc
libilbc decoder wrapper.
libilbc allows libavcodec to decode the Internet Low Bitrate Codec (iLBC) audio codec. requires the presence of the libilbc headers and library during configuration. you need to explicitly configure the build with --enable-libilbc.
Options
the following option is supported by the libilbc wrapper:
enhanceโ enable the enhancement of the decoded audio when set to1. the default value is0(disabled) โจ
๐ libmpeghdec
libmpeghdec decoder wrapper.
libmpeghdec allows libmpeghdec to decode the MPEG-H 3D audio codec. requires the presence of the libmpeghdec headers and library during configuration. you need to explicitly configure the build with --enable-libmpeghdec --enable-nonfree ๐ฅ (yeah, both of those, together, don't forget the second one bestie)
๐ libopencore-amrnb
libopencore-amrnb decoder wrapper.
libopencore-amrnb allows libavcodec to decode the Adaptive Multi-Rate Narrowband audio codec. using it requires the presence of the libopencore-amrnb headers and library during configuration. you need to explicitly configure the build with --enable-libopencore-amrnb.
an FFmpeg native decoder for AMR-NB exists, so users can decode AMR-NB without this library ๐ good to know fr fr.
๐ง libopencore-amrwb
libopencore-amrwb decoder wrapper.
libopencore-amrwb allows libavcodec to decode the Adaptive Multi-Rate Wideband audio codec. using it requires the presence of the libopencore-amrwb headers and library during configuration. you need to explicitly configure the build with --enable-libopencore-amrwb.
an FFmpeg native decoder for AMR-WB exists, so users can decode AMR-WB without this library ๐ same energy as the narrowband one.
๐ถ libopus
libopus decoder wrapper.
libopus allows libavcodec to decode the Opus Interactive Audio Codec. requires the presence of the libopus headers and library during configuration. you need to explicitly configure the build with --enable-libopus.
an FFmpeg native decoder for Opus exists, so users can decode Opus without this library ๐ iconic, honestly.
๐ SUBTITLES DECODERS ๐
๐ libaribb24
Okay so this one is an ARIB STD-B24 caption decoder. It implements profiles A and C of the ARIB STD-B24 standard. Slay, standardization!
โจ libaribb24 Decoder Options โจ
-aribb24-base-path pathโ sets the base path for the libaribb24 library. It's used for reading config files (for custom unicode conversions) and for dumping non-text symbols as images under that location. It's unset by default, bestie.-aribb24-skip-ruby-text booleanโ tells the decoder wrapper to skip text blocks that contain half-height ruby text. It's enabled by default. Not me skipping the ruby text ๐
๐ฆ libaribcaption
Yet another ARIB STD-B24 caption decoder, but this one uses the external libaribcaption library. It implements profiles A and C of the Japanese ARIB STD-B24 standard, Brazilian ABNT NBR 15606-1, and the Philippines version of ISDB-T. Iconic international range fr fr.
It requires the presence of the libaribcaption headers and library (<https://github.com/xqq/libaribcaption>) during configuration. You need to explicitly configure the build with "--enable-libaribcaption". Also important: if both libaribb24 and libaribcaption are enabled, libaribcaption decoder precedes. It's giving main character energy ๐
๐ธ libaribcaption Decoder Options ๐ธ
-sub_type subtitle_typeโ specifies the format of the decoded subtitles. The vibes are:bitmapโ graphical image.assโ ASS formatted text.textโ simple text based output without formatting.
The default is ass, same as the libaribb24 decoder. Some present players (e.g., mpv) expect ASS format for ARIB caption.
-caption_encoding encoding_schemeโ specifies the encoding scheme of input subtitle text. Options:autoโ automatically detect text encoding (default).jisโ 8bit-char JIS encoding defined in ARIB STD B24. This encoding is used in Japan for ISDB captions.utf8โ UTF-8 encoding defined in ARIB STD B24. This encoding is used in Philippines for ISDB-T captions.latinโ Latin character encoding defined in ABNT NBR 15606-1. This encoding is used in South America for SBTVD / ISDB-Tb captions.
-font font_name[,font_name2,...]โ specify a comma-separated list of font family names to be used forbitmaporasstype subtitle rendering. Only the first font name is used forasstype subtitle. If not specified, it uses the internally defined default font family.-ass_single_rect booleanโ ARIB STD-B24 specifies that some captions may be displayed at different positions at a time (multi-rectangle subtitle). Since some players (e.g., old mpv) can't handle multiple ASS rectangles in a single AVSubtitle, or multiple ASS rectangles of indeterminate duration with the same start timestamp, this option can change the behavior so that all the texts are displayed in a single ASS rectangle. The default isfalse. If your player cannot handle AVSubtitles with multiple ASS rectangles properly, set this option totrueor defineASS_SINGLE_RECT=1to change default behavior at compilation.-force_outline_text booleanโ specify whether to always render outline text for all characters regardless of the indication by character style. The default isfalse.-outline_width number (0.0 - 3.0)โ specify width for outline text, in dots (relative). The default is1.5.-ignore_background booleanโ specify whether to ignore background color rendering. The default isfalse.-ignore_ruby booleanโ specify whether to ignore rendering for ruby-like (furigana) characters. The default isfalse.-replace_drcs booleanโ specify whether to render replaced DRCS characters as Unicode characters. The default istrue.-replace_msz_ascii booleanโ specify whether to replace MSZ (Middle Size; half width) fullwidth alphanumerics with halfwidth alphanumerics. The default istrue.-replace_msz_japanese booleanโ specify whether to replace some MSZ (Middle Size; half width) fullwidth japanese special characters with halfwidth ones. The default istrue.-replace_msz_glyph booleanโ specify whether to replace MSZ (Middle Size; half width) characters with halfwidth glyphs if the fonts supports it. This option works under FreeType or DirectWrite renderer with Adobe-Japan1 compliant fonts. e.g., IBM Plex Sans JP, Morisawa BIZ UDGothic, Morisawa BIZ UDMincho, Yu Gothic, Yu Mincho, and Meiryo. The default istrue.-canvas_size image_sizeโ specify the resolution of the canvas to render subtitles to; usually, this should be frame size of input video. This only applies when"-subtitle_type"is set tobitmap.
The libaribcaption decoder assumes input frame size for bitmap rendering as below:
PROFILE_A: 1440 x 1080 with SAR (PAR) 4:3PROFILE_C: 320 x 180 with SAR (PAR) 1:1
If the actual frame size of input video does not match the above assumption, the rendered captions may be distorted ๐ญ To make the captions undistorted, add "-canvas_size" option to specify actual input video size.
Note that the "-canvas_size" option is not required for video with different size but same aspect ratio. In such cases, the caption will be stretched or shrunk to actual video size if "-canvas_size" option is not specified. If "-canvas_size" option is specified with different size, the caption will be stretched or shrunk as specified size with calculated SAR.
๐ libaribcaption decoder usage examples ๐
Display MPEG-TS file with ARIB subtitle by "ffplay" tool:
ffplay -sub_type bitmap MPEG.TS
Display MPEG-TS file with input frame size 1920x1080 by "ffplay" tool:
ffplay -sub_type bitmap -canvas_size 1920x1080 MPEG.TS
Embed ARIB subtitle in transcoded video:
ffmpeg -sub_type bitmap -i src.m2t -filter_complex "[0:v][0:s]overlay" -vcodec h264 dest.mp4
๐ง dvbsub
Options
compute_clutโ the values are:-2โ compute clut once if no matching CLUT is in the stream.-1โ compute clut if no matching CLUT is in the stream.0โ never compute CLUT.1โ always compute CLUT and override the one provided in the stream.
dvb_substreamโ selects the dvb substream, or all substreams if-1, which is default.
๐ dvdsub
This codec decodes the bitmap subtitles used in DVDs; the same subtitles can also be found in VobSub file pairs and in some Matroska files. Lowkey everywhere.
Options
paletteโ specify the global palette used by the bitmaps. When stored in VobSub, the palette is normally specified in the index file; in Matroska, the palette is stored in the codec extra-data in the same format as in VobSub. In DVDs, the palette is stored in the IFO file, and therefore not available when reading from dumped VOB files.
The format for this option is a string containing 16 24-bits hexadecimal numbers (without 0x prefix) separated by commas, for example "0d00ee, ee450d, 101010, eaeaea, 0ce60b, ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1, 7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b".
ifo_paletteโ specify the IFO file from which the global palette is obtained. (experimental) ๐forced_subs_onlyโ only decode subtitle entries marked as forced. Some titles have forced and non-forced subtitles in the same track. Setting this flag to1will only keep the forced subtitles. Default value is0.
๐ libzvbi-teletext
Libzvbi allows libavcodec to decode DVB teletext pages and DVB teletext subtitles. It requires the presence of the libzvbi headers and library during configuration. You need to explicitly configure the build with "--enable-libzvbi".
Options
txt_pageโ list of teletext page numbers to decode. Pages that do not match the specified list are dropped. You may use the special"*"string to match all pages, or"subtitle"to match all subtitle pages. Default value is*.txt_default_regionโ set default character set used for decoding, a value between0and87(see ETS 300 706, Section 15, Table 32). Default value is-1, which does not override the libzvbi default. This option is needed for some legacy level 1.0 transmissions which cannot signal the proper charset.txt_chop_topโ discards the top teletext line. Default value is1.txt_formatโ specifies the format of the decoded subtitles:bitmapโ the default format, you should use this for teletext pages, because certain graphics and colors cannot be expressed in simple text or even ASS.textโ simple text based output without formatting.assโ formatted ASS output, subtitle pages and teletext pages are returned in different styles, subtitle pages are stripped down to text, but an effort is made to keep the text alignment and the formatting.
txt_leftโ X offset of generated bitmaps, default is0.txt_topโ Y offset of generated bitmaps, default is0.txt_chop_spacesโ chops leading and trailing spaces and removes empty lines from the generated text. This option is useful for teletext based subtitles where empty spaces may be present at the start or at the end of the lines or empty lines may be present between the subtitle lines because of double-sized teletext characters. Default value is1.txt_durationโ sets the display duration of the decoded teletext pages or subtitles in milliseconds. Default value is-1which means infinity or until the next subtitle event comes.txt_transparentโ force transparent background of the generated teletext bitmaps. Default value is0which means an opaque background.txt_opacityโ sets the opacity (0-255) of the teletext background. Iftxt_transparentis not set, it only affects characters between a start box and an end box, typically subtitles. Default value is0iftxt_transparentis set,255otherwise.
โญ BITSTREAM FILTERS โญ
Okay bestie, when you configure your FFmpeg build, all the supported bitstream filters are enabled by default. You can list all available ones using the configure option "--list-bsfs".
You can disable all the bitstream filters using the configure option "--disable-bsfs", and selectively enable any bitstream filter using the option "--enable-bsf=BSF", or you can disable a particular bitstream filter using the option "--disable-bsf=BSF". Mix and match, that's the vibe ๐
The option "-bsfs" of the ff* tools will display the list of all the supported bitstream filters included in your build.
The ff* tools have a -bsf option applied per stream, taking a comma-separated list of filters, whose parameters follow the filter name after a '='.
ffmpeg -i INPUT -c:v copy -bsf:v filter1[=opt1=str1:opt2=str2][,filter2] OUTPUT
ok bestie, so down below is the full rundown of every bitstream filter that's currently available, plus their params if they have any ๐
๐ aac_adtstoasc
Turns an MPEG-2/4 AAC ADTS thingy into an MPEG-4 Audio Specific Configuration bitstream. Fancy.
What it actually does: builds an MPEG-4 AudioSpecificConfig out of an MPEG-2/4 ADTS header, then yeets the ADTS header away. โจ
So when do you need it? Classic case: you're copying an AAC stream from a raw ADTS AAC or an MPEG-TS container over to MP4A-LATM, or to an FLV file, or to MOV/MP4 files and related formats like 3GP or M4A. Heads up though: it gets auto-inserted for MP4A-LATM and MOV/MP4 and related formats, so it's already handling itself there ๐
๐ฆ av1_metadata
Modifies metadata embedded in an AV1 stream. Little glow-up for your headers.
tdโ insert or remove temporal delimiter OBUs in all temporal units of the stream.insertโ drops a TD at the beginning of every TU that doesn't already have one.removeโ deletes the TD from the beginning of every TU that has one.
color_primaries,transfer_characteristics,matrix_coefficientsโ set the color description fields in the stream (peep AV1 section 6.4.2 ๐).color_rangeโ set the color range in the stream (see AV1 section 6.4.2; note that this can't be set for streams using BT.709 primaries, sRGB transfer characteristic and identity (RGB) matrix coefficients).tvโ limited range.pcโ full range.
chroma_sample_positionโ set the chroma sample location in the stream (see AV1 section 6.4.2). This can only be set for 4:2:0 streams, no cap.verticalโ left position (matching the default in MPEG-2 and H.264).colocatedโ top-left position.
tick_rateโ set the tick rate (time_scale / num_units_in_display_tick) in the timing info in the sequence header.num_ticks_per_pictureโ set the number of ticks in each picture, to indicate that the stream has a fixed framerate. Ignored iftick_rateisn't also set ๐ซถdelete_paddingโ deletes Padding OBUs. bye bye padding โจ
๐ chomp
Removes zero padding at the end of a packet. That's it. Snack-sized filter, we stan.
๐ dca_core
Extracts the core from a DCA/DTS stream, dropping extensions like DTS-HD. Just the core, bestie.
๐ dovi_rpu
Manipulates Dolby Vision metadata in a HEVC/AV1 bitstream, and optionally enables metadata compression.
stripโ if enabled, strips all Dolby Vision metadata (configuration record + RPU data blocks) from the stream.compressionโ which compression level to enable.noneโ no metadata compression.limitedโ limited metadata compression scheme. Should be compatible with most devices. This is the default.extendedโ extended metadata compression. Devices are not required to support this. Note that this level currently behaves the same aslimitedin libavcodec ๐
๐ dump_extra
Adds extradata to the beginning of the filtered packets โ except when those packets already exactly begin with the extradata that was intended to be added. Like, it checks first, it's polite ๐
freqโ the additional argument specifies which packets should be filtered. It accepts these values:k,keyframeโ add extradata to all key packets.e,allโ add extradata to all packets.
If you don't specify it, it's assumed to be k.
Example time! This ffmpeg command forces a global header (so individual packet headers get disabled) in the H.264 packets made by the "libx264" encoder, but then corrects them by adding the header stored in extradata to the key packets:
ffmpeg -i INPUT -map 0 -flags:v +global_header -c:v libx264 -bsf:v dump_extra out.ts
๐ง dv_error_marker
Blocks in DV that are marked as damaged get replaced by blocks of the specified color. Damage control but make it aesthetic.
colorโ the color to replace damaged blocks by.staโ a 16 bit mask specifying which of the 16 possible error status values are to be replaced by colored blocks.0xFFFEis the default, which replaces all non 0 error status values.okโ no error, no concealment.errโ error, no concealment.resโ reserved.notokโ error or concealment.notresโ not reserved.Aa,Ba,Ca,Ab,Bb,Cb,A,B,C,a,b,erri,erruโ the specific error status code.- see page 44-46 or section 5.5 of <http://web.archive.org/web/20060927044735/http://www.smpte.org/smpte_store/standards/pdf/s314m.pdf>
๐ซถ eac3_core
Extracts the core from an E-AC-3 stream, dropping extra channels. Core only, no extras ๐
โญ eia608_to_smpte436m
Converts from an "EIA_608" stream to an "SMPTE_436M_ANC" data stream, wrapping the closed captions in CTA-708 CDP VANC packets. Iconic little pipeline honestly.
line_numberโ choose which line number the generated VANC packets should go on. You generally want either line 9 (the default) or 11.wrapping_typeโ choose the SMPTE 436M wrapping type, defaults tovanc_frame. It accepts the values:vanc_frameโ VANC frame (interlaced or segmented progressive frame).vanc_field_1vanc_field_2vanc_progressive_frame
sample_codingโ choose the SMPTE 436M sample coding, defaults to8bit_luma. It accepts the values:8bit_lumaโ 8-bit component luma samples.8bit_color_diffโ 8-bit component color difference samples.8bit_luma_and_color_diffโ 8-bit component luma and color difference samples.10bit_lumaโ 10-bit component luma samples.10bit_color_diffโ 10-bit component color difference samples.10bit_luma_and_color_diffโ 10-bit component luma and color difference samples.8bit_luma_parity_errorโ 8-bit component luma samples with parity error.8bit_color_diff_parity_errorโ 8-bit component color difference samples with parity error.8bit_luma_and_color_diff_parity_errorโ 8-bit component luma and color difference samples with parity error.
initial_cdp_sequence_cntrโ the initial value of the CDP's 16-bit unsigned integer"cdp_hdr_sequence_cntr"and"cdp_ftr_sequence_cntr"fields. Defaults to0.cdp_frame_rateโ set the CDP's"cdp_frame_rate"field. This doesn't actually change the timing of the data stream, it just changes the values inserted in that field in the generated CDP packets. Defaults to30000/1001.
๐ธ extract_extradata
Extracts the in-band extradata. Ok so let me explain this one properly, because it slaps:
Certain codecs let the long-term headers (like MPEG-2 sequence headers, or H.264/HEVC (VPS/)SPS/PPS) be transmitted either "in-band" โ meaning as part of the bitstream that contains the coded frames โ or "out of band" (like, at the container level). That second form is what FFmpeg calls "extradata" โจ
This bitstream filter sniffs out the in-band headers and makes them available as extradata.
removeโ when this option is enabled, the long-term headers get removed from the bitstream after extraction.
๐ฅ filter_units
Removes units with types in โ or not in โ a given set from the stream. Bouncer energy, honestly.
pass_typesโ list of unit types or ranges of unit types to pass through while removing all others. You write it as a'|'-separated list of unit type values or ranges of values with'-'.remove_typesโ identical topass_types, except the units in the given set are removed and all others are passed through.
The types used by pass_types and remove_types correspond to NAL unit types (nal_unit_type) in H.264, HEVC and H.266 (see Table 7-1 in the H.264 and HEVC specifications, or Table 5 in the H.266 specification), to marker values for JPEG (without 0xFF prefix) and to start codes without start code prefix (i.e. the byte following the 0x000001) for MPEG-2. For VP8 and VP9, every unit has type zero ๐
Extradata is unchanged by this transformation, but note that if the stream contains inline parameter sets then the output may be unusable if they are removed ๐ญ
Example time, bestie:
To remove all non-VCL NAL units from an H.264 stream:
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=pass_types=1-5' OUTPUT
To remove all AUDs, SEI and filler from an H.265 stream:
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=remove_types=35|38-40' OUTPUT
To remove all user data from a MPEG-2 stream, including Closed Captions:
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=remove_types=178' OUTPUT
To remove all SEI from a H264 stream, including Closed Captions:
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=remove_types=6' OUTPUT
To remove all prefix and suffix SEI from a HEVC stream, including Closed Captions and dynamic HDR:
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=remove_types=39|40' OUTPUT
๐ hapqa_extract
Extracts the Rgb or Alpha part of an HAPQA file โ with no recompression โ so you can create an HAPQ or an HAPAlphaOnly file. Surgical ๐
textureโ specifies the texture to keep.coloralpha
Convert HAPQA to HAPQ:
ffmpeg -i hapqa_inputfile.mov -c copy -bsf:v hapqa_extract=texture=color -tag:v HapY -metadata:s:v:0 encoder="HAPQ" hapq_file.mov
Convert HAPQA to HAPAlphaOnly:
ffmpeg -i hapqa_inputfile.mov -c copy -bsf:v hapqa_extract=texture=alpha -tag:v HapA -metadata:s:v:0 encoder="HAPAlpha Only" hapalphaonly_file.mov
๐ h264_metadata
Modifies metadata embedded in an H.264 stream. The big one, get comfy โจ
audโ insert or remove AUD NAL units in all access units of the stream.passinsertremove
Default is pass.
sample_aspect_ratioโ set the sample aspect ratio of the stream in the VUI parameters. See H.264 table E-1.overscan_appropriate_flagโ set whether the stream is suitable for display using overscan or not (see H.264 section E.2.1).video_format,video_full_range_flagโ set the video format in the stream (see H.264 section E.2.1 and table E-2).colour_primaries,transfer_characteristics,matrix_coefficientsโ set the colour description in the stream (see H.264 section E.2.1 and tables E-3, E-4 and E-5).chroma_sample_loc_typeโ set the chroma sample location in the stream (see H.264 section E.2.1 and figure E-1).tick_rateโ set the tick rate (time_scale / num_units_in_tick) in the VUI parameters. This is the smallest time unit representable in the stream, and in many cases represents the field rate of the stream (double the frame rate) ๐fixed_frame_rate_flagโ set whether the stream has fixed framerate. Typically this indicates that the framerate is exactly half the tick rate, but the exact meaning depends on interlacing and the picture structure (see H.264 section E.2.1 and table E-6).zero_new_constraint_set_flagsโ okay so this one zerosconstraint_set4_flagandconstraint_set5_flagin the SPS. These bits were reserved in a previous version of the H.264 spec, so some hardware decoders literally require them to be zero. The result of zeroing this is still a valid bitstream. ๐ซถcrop_left,crop_right,crop_top,crop_bottomโ these set the frame cropping offsets in the SPS. These values will replace the current ones if the stream is already cropped. Theyโre set in pixels, and note that some sizes may not be representable if the chroma is subsampled or the stream is interlaced (see H.264 section7.4.2.1.1). ๐sei_user_dataโ inserts a string as SEI unregistered user data. The argument must be of the formUUID+string, where the UUID is as hex digits possibly separated by hyphens, and the string can be anything. For example,086f3693-b7b3-4f2c-9653-21492feee5b8+hellowill insert the string"hello"associated with the given UUID. โจdelete_fillerโ deletes both filler NAL units and filler SEI messages. Bye, filler. ๐ซกdisplay_orientationโ insert, extract or remove Display orientation SEI messages. See H.264 sectionD.1.27andD.2.27for syntax and semantics. The modes arepass,insert,remove,extract; default ispass. Insert mode works in conjunction withrotateandflipoptions. Any pre-existing Display orientation messages will be removed ininsertorremovemode.extractmode attaches the display matrix to the packet as side data. ๐rotateโ set rotation in display orientation SEI (anticlockwise angle in degrees). Range is-360to+360. Default isNaN. ๐flipโ set flip in display orientation SEI. The values arehorizontalandvertical. Default is unset. ๐levelโ set the level in the SPS. Refer to H.264 sectionA.3and tablesA-1toA-5. The argument must be the name of a level (for example,4.2), alevel_idcvalue (for example,42), or the special nameautoindicating that the filter should attempt to guess the level from the input stream properties. ๐๏ธ
h264_mp4toannexb
Convert an H.264 bitstream from length prefixed mode to start code prefixed mode (as defined in the Annex B of the ITU-T H.264 specification). This is required by some streaming formats, typically the MPEG-2 transport stream format (muxer "mpegts"). ๐
For example, to remux an MP4 file containing an H.264 stream to mpegts format with ffmpeg, you can use the command:
ffmpeg -i INPUT.mp4 -codec copy -bsf:v h264_mp4toannexb OUTPUT.ts
Please note that this filter is auto-inserted for MPEG-TS (muxer "mpegts") and raw H.264 (muxer "h264") output formats. No cap. โจ
h264_redundant_pps
This applies a specific fixup to some Blu-ray BDMV H264 streams which contain redundant PPSs. The PPSs modify irrelevant parameters of the stream, confusing other transformations which require the correct extradata. ๐ญ
The encoder used on these impacted streams adds extra PPSs throughout the stream, varying the initial QP and whether weighted prediction was enabled. This causes issues after copying the stream into a global header container, as the starting PPS is not suitable for the rest of the stream. One side effect, for example, is seeking will return garbled output until a new PPS appears. ๐
This BSF removes the extra PPSs and rewrites the slice headers such that the stream uses a single leading PPS in the global header, which resolves the issue. Slay. ๐
hevc_metadata
Modify metadata embedded in an HEVC stream. ๐ฆ
audโ insert or remove AUD NAL units in all access units of the stream. Values:insert,remove.sample_aspect_ratioโ set the sample aspect ratio in the stream in the VUI parameters.video_format,video_full_range_flagโ set the video format in the stream (see H.265 sectionE.3.1and tableE.2).colour_primaries,transfer_characteristics,matrix_coefficientsโ set the colour description in the stream (see H.265 sectionE.3.1and tablesE.3,E.4andE.5).chroma_sample_loc_typeโ set the chroma sample location in the stream (see H.265 sectionE.3.1and figureE.1).tick_rateโ set the tick rate in the VPS and VUI parameters (time_scale / num_units_in_tick). Combined withnum_ticks_poc_diff_one, this can set a constant framerate in the stream. Note that it is likely to be overridden by container parameters when the stream is in a container. โฑ๏ธnum_ticks_poc_diff_oneโ setpoc_proportional_to_timing_flagin VPS and VUI and use this value to setnum_ticks_poc_diff_one_minus1(see H.265 sections7.4.3.1andE.3.1). Ignored iftick_rateis not also set. ๐crop_left,crop_right,crop_top,crop_bottomโ set the conformance window cropping offsets in the SPS. These values will replace the current ones if the stream is already cropped. These fields are set in pixels. Note that some sizes may not be representable if the chroma is subsampled (H.265 section7.4.3.2.1). ๐width,heightโ set width and height after crop. ๐levelโ set the level in the VPS and SPS. See H.265 sectionA.4and tablesA.6andA.7. The argument must be the name of a level (for example,5.1), ageneral_level_idcvalue (for example,153for level5.1), or the special nameautoindicating that the filter should attempt to guess the level from the input stream properties. ๐๏ธ
hevc_mp4toannexb
Convert an HEVC/H.265 bitstream from length prefixed mode to start code prefixed mode (as defined in the Annex B of the ITU-T H.265 specification). This is required by some streaming formats, typically the MPEG-2 transport stream format (muxer "mpegts"). ๐
For example, to remux an MP4 file containing an HEVC stream to mpegts format with ffmpeg, you can use the command:
ffmpeg -i INPUT.mp4 -codec copy -bsf:v hevc_mp4toannexb OUTPUT.ts
Please note that this filter is auto-inserted for MPEG-TS (muxer "mpegts") and raw HEVC/H.265 (muxer "h265" or "hevc") output formats. โจ
imxdump
Modifies the bitstream to fit in MOV and to be usable by the Final Cut Pro decoder. This filter only applies to the mpeg2video codec, and is likely not needed for Final Cut Pro 7 and newer with the appropriate -tag:v. ๐ฌ
For example, to remux 30 MB/sec NTSC IMX to MOV:
ffmpeg -i input.mxf -c copy -bsf:v imxdump -tag:v mx3n output.mov
mjpeg2jpeg
Convert MJPEG/AVI1 packets to full JPEG/JFIF packets. ๐ธ
MJPEG is a video codec wherein each video frame is essentially a JPEG image. The individual frames can be extracted without loss, e.g. by
ffmpeg -i ../some_mjpeg.avi -c:v copy frames_%d.jpg
Unfortunately, these chunks are incomplete JPEG images, because they lack the DHT segment required for decoding. Quoting from http://www.digitalpreservation.gov/formats/fdd/fdd000063.shtml:
Avery Lee, writing in the rec.video.desktop newsgroup in 2001, commented that "MJPEG, or at least the MJPEG in AVIs having the MJPG fourcc, is restricted JPEG with a fixed -- and omitted -- Huffman table. The JPEG must be YCbCr colorspace, it must be 4:2:2, and it must use basic Huffman encoding, not arithmetic or progressive. . . . You can indeed extract the MJPEG frames and decode them with a regular JPEG decoder, but you have to prepend the DHT segment to them, or else the decoder won't have any idea how to decompress the data. The exact table necessary is given in the OpenDML spec."
This bitstream filter patches the header of frames extracted from an MJPEG stream (carrying the AVI1 header ID and lacking a DHT segment) to produce fully qualified JPEG images. ๐ฅ
ffmpeg -i mjpeg-movie.avi -c:v copy -bsf:v mjpeg2jpeg frame_%d.jpg
exiftran -i -9 frame*.jpg
ffmpeg -i frame_%d.jpg -c:v copy rotated.avi
mjpegadump
Add an MJPEG A header to the bitstream, to enable decoding by Quicktime. ๐
mov2textsub
Extract a representable text file from MOV subtitles, stripping the metadata header from each subtitle packet. See also the text2movsub filter. ๐
mpeg2_metadata
Modify metadata embedded in an MPEG-2 stream. ๐ฆ
display_aspect_ratioโ set the display aspect ratio in the stream. The following fixed values are supported:4/3,16/9,221/100. Any other value will result in square pixels being signalled instead (see H.262 section6.3.3and table6-3).frame_rateโ set the frame rate in the stream. This is constructed from a table of known values combined with a small multiplier and divisor โ if the supplied value is not exactly representable, the nearest representable value will be used instead (see H.262 section6.3.3and table6-4). โฑ๏ธvideo_formatโ set the video format in the stream (see H.262 section6.3.6and table6-6).colour_primaries,transfer_characteristics,matrix_coefficientsโ set the colour description in the stream (see H.262 section6.3.6and tables6-7,6-8and6-9). ๐
mpeg4_unpack_bframes
Unpack DivX-style packed B-frames. ๐ง
DivX-style packed B-frames are not valid MPEG-4 and were only a workaround for the broken Video for Windows subsystem. They use more space, can cause minor AV sync issues, require more CPU power to decode (unless the player has some decoded picture queue to compensate the 2,0,2,0 frame per packet style) and cause trouble if copied into a standard container like mp4 or mpeg-ps/ts, because MPEG-4 decoders may not be able to decode them, since they are not valid MPEG-4. ๐ญ
For example, to fix an AVI file containing an MPEG-4 stream with DivX-style packed B-frames using ffmpeg, you can use the command:
ffmpeg -i INPUT.avi -codec copy -bsf:v mpeg4_unpack_bframes OUTPUT.avi
noise
Damages the contents of packets or simply drops them without damaging the container. Can be used for fuzzing or testing error resilience/concealment. ๐
Parameters:
amountโ accepts an expression whose evaluation per-packet determines how often bytes in that packet will be modified. A value below0will result in a variable frequency. Default is0which results in no modification. However, if neitheramountnordropis specified,amountwill be set to-1. See below for accepted variables ๐dropโ okay so this takes an expression that gets evaluated per-packet, and its value decides whether that packet gets dropped. If it evaluates to a positive value, the packet is dropped. If it evaluates to a negative value, thereโs a variable chance it gets dropped, roughly inverse in proportion to the magnitude of the value. Default is0, which results in no drops. See below for accepted variables, bestie.dropamountโ takes a non-negative integer, and that assigns a variable chance of the packet being dropped, roughly inverse in proportion to the value. Default is0, which results in no drops. This option is kept for backwards compatibility and is equivalent to settingdropto a negative value with the same magnitude, i.e.dropamount=4is the same asdrop=-4. Ignored ifdropis also specified.
Both amount and drop accept expressions containing the following variables:
nโ The index of the packet, starting from zero.tbโ The timebase for packet timestamps.ptsโ Packet presentation timestamp.dtsโ Packet decoding timestamp.noptsโ Constant representingAV_NOPTS_VALUE.startptsโ First non-AV_NOPTS_VALUEPTS seen in the stream.startdtsโ First non-AV_NOPTS_VALUEDTS seen in the stream.duration,dโ Packet duration, in timebase units.posโ Packet position in input; may be-1when unknown or not set.sizeโ Packet size, in bytes.keyโ Whether packet is marked as a keyframe.stateโ A pseudo random integer, primarily derived from the content of packet payload.
๐ Examples ๐
Apply modification to every byte but donโt drop any packets.
ffmpeg -i INPUT -c copy -bsf noise=1 output.mkv
Drop every video packet not marked as a keyframe after timestamp 30s but do not modify any of the remaining packets.
ffmpeg -i INPUT -c copy -bsf:v noise=drop='gt(pts*tb\,30)*not(key)' output.mkv
Drop one second of audio every 10 seconds and add some random noise to the rest.
ffmpeg -i INPUT -c copy -bsf:a noise=amount=-1:drop='between(mod(pts*tb\,10)\,9\,10)' output.mkv
๐ฆ null ๐ฆ
This bitstream filter passes the packets through unchanged. Literally the chillest.
๐ pcm_rechunk ๐
Repacketize PCM audio to a fixed number of samples per packet or a fixed packet rate per second. This is similar to the asetnsamples audio filter but works on audio packets instead of audio frames.
nb_out_samples,nโ Set the number of samples per each output audio packet. The number is intended as the number of samples per each channel. Default value is1024.pad,pโ If set to1, the filter will pad the last audio packet with silence, so that it will contain the same number of samples (or roughly the same number of samples, seeframe_rate) as the previous ones. Default value is1.frame_rate,rโ This option makes the filter output a fixed number of packets per second instead of a fixed number of samples per packet. If the audio sample rate is not divisible by the frame rate then the number of samples will not be constant but will vary slightly so that each packet will start as close to the frame boundary as possible. Using this option has precedence overnb_out_samples.
You can generate the well known 1602-1601-1602-1601-1602 pattern of 48kHz audio for NTSC frame rate using the frame_rate option.
ffmpeg -f lavfi -i sine=r=48000:d=1 -c pcm_s16le -bsf pcm_rechunk=r=30000/1001 -f framecrc -
๐ pgs_frame_merge ๐
Merge a sequence of PGS Subtitle segments ending with an "end of display set" segment into a single packet.
This is required by some containers that support PGS subtitles (muxer matroska).
๐
prores_metadata ๐
Modify color property metadata embedded in prores stream.
color_primariesโ Set the color primaries. Available values are:autoโ Keep the same color primaries property (default).unknownbt709bt470bgโ BT601 625smpte170mโ BT601 525bt2020smpte431โ DCI P3smpte432โ P3 D65
transfer_characteristicsโ Set the color transfer. Available values are:autoโ Keep the same transfer characteristics property (default).unknownbt709โ BT 601, BT 709, BT 2020smpte2084โ SMPTE ST 2084arib-std-b67โ ARIB STD-B67
matrix_coefficientsโ Set the matrix coefficient. Available values are:autoโ Keep the same colorspace property (default).unknownbt709smpte170mโ BT 601bt2020nc
Set Rec709 colorspace for each frame of the file
ffmpeg -i INPUT -c copy -bsf:v prores_metadata=color_primaries=bt709:color_trc=bt709:colorspace=bt709 output.mov
Set Hybrid Log-Gamma parameters for each frame of the file
ffmpeg -i INPUT -c copy -bsf:v prores_metadata=color_primaries=bt2020:color_trc=arib-std-b67:colorspace=bt2020nc output.mov
๐ง remove_extra ๐ง
Remove extradata from packets.
It accepts the following parameter:
freqโ Set which frame types to remove extradata from.kโ Remove extradata from non-keyframes only.keyframeโ Remove extradata from keyframes only.e,allโ Remove extradata from all frames.
โญ setts โญ
Set PTS and DTS in packets.
It accepts the following parameters:
ts,pts,dtsโ Set expressions for PTS, DTS or both.durationโ Set expression for duration.time_baseโ Set output time base.prescaleโ Set whether to convert time fields to user-set output time base before evaluation of expressions. Defaults to0.
The expressions are evaluated through the eval API and can contain the following constants:
Nโ The count of the input packet. Starting from 0.TSโ The demux timestamp in input in case oftsordtsoption or presentation timestamp in case ofptsoption.POSโ The original position in the file of the packet, or undefined if undefined for the current packetDTSโ The demux timestamp in input.PTSโ The presentation timestamp in input.DURATIONโ The duration in input.STARTDTSโ The DTS of the first packet.STARTPTSโ The PTS of the first packet.PREV_INDTSโ The previous input DTS.PREV_INPTSโ The previous input PTS.PREV_INDURATIONโ The previous input duration.PREV_OUTDTSโ The previous output DTS.PREV_OUTPTSโ The previous output PTS.PREV_OUTDURATIONโ The previous output duration.NEXT_DTSโ The next input DTS.NEXT_PTSโ The next input PTS.NEXT_DURATIONโ The next input duration.TBโ The timebase in which time fields are denominated. The user-set output timebase ifprescaleis enabled, else the input timebase.TB_OUTโ The output timebase.SRโ The sample rate of stream packet belongs.NOPTSโ TheAV_NOPTS_VALUEconstant.
For example, to set PTS equal to DTS (not recommended if B-frames are involved):
ffmpeg -i INPUT -c:a copy -bsf:a setts=pts=DTS out.mkv
๐ showinfo ๐
Log basic packet information. Mainly useful for testing, debugging, and development.
๐ฆ smpte436m_to_eia608 ๐ฆ
Convert from a SMPTE_436M_ANC data stream to a EIA_608 stream, extracting the closed captions from CTA-708 CDP VANC packets, and ignoring all other data.
๐ text2movsub ๐
Convert text subtitles to MOV subtitles (as used by the mov_text codec) with metadata headers.
See also the mov2textsub filter.
๐ฅ trace_headers ๐ฅ
Log trace output containing all syntax elements in the coded stream headers (everything above the level of individual coded blocks). This can be useful for debugging low-level stream issues.
Supports AV1, H.264, H.265, (M)JPEG, MPEG-2 and VP9, but depending on the build only a subset of these may be available.
๐ truehd_core ๐
Extract the core from a TrueHD stream, dropping ATMOS data.
๐ vp9_metadata ๐
Modify metadata embedded in a VP9 stream.
color_spaceโ Set the color space value in the frame header. Note that any frame set to RGB will be implicitly set to PC range and that RGB is incompatible with profiles 0 and 2.unknownbt601bt709smpte170smpte240bt2020rgb
color_rangeโ Set the color range value in the frame header. Note that any value imposed by the color space will take precedence over this value.tvpc
๐ธ vp9_superframe ๐ธ
Merge VP9 invisible (alt-ref) frames back into VP9 superframes. This fixes merging of split/segmented VP9 streams where the alt-ref frame was split from its visible counterpart.
๐ฆ vp9_superframe_split ๐ฆ
Split VP9 superframes into single frames.
๐
vp9_raw_reorder ๐
Given a VP9 stream with correct timestamps but possibly out of order, insert additional show-existing-frame packets to correct the ordering.
๐ FORMAT OPTIONS ๐
okay so the libavformat library ships with some generic global options, and you can set them on, like, all the muxers and demuxers. and on top of that? each muxer or demuxer might support its own so-called private options that are specific to that one component. bestie behaviour honestly ๐
you set options by specifying -option value in the FFmpeg tools, or by setting the value explicitly in the AVFormatContext options, or by using the libavutil/opt.h API if you're doing the programmatic thing โจ
the list of supported options follows, and yes we're going through all of them ๐ซถ
avioflags flags(input/output) โ Possible values:directโ reduce buffering ๐ฆ
probesize integer(input) โ sets the probing size in bytes, like, the size of the data that gets analyzed to get stream information. a higher value = detecting more info in case it's dispersed into the stream, but it will increase latency, no cap. must be an integer not lesser than 32. it's5000000by default.max_probe_packets integer(input) โ the max number of buffered packets when probing a codec. default is2500packets โจpacketsize integer(output) โ sets packet size.fflags flagsโ sets format flags. some are implemented for a limited number of formats only, iykyk.
Possible values for input files:
discardcorruptโ discard corrupted packets ๐๏ธfastseekโ enable fast, but inaccurate seeks for some formats (yes it's giving "we ball" energy)genptsโ generate missing PTS if DTS is presentigndtsโ ignore DTS if PTS is also set. in case the PTS is set, the DTS value is set toNOPTS. this is ignored when thenofillinflag is set ๐ignidxโ ignore indexnobufferโ reduce the latency introduced by buffering during initial input streams analysisnofillinโ do not fill in missing values in packet fields that can be exactly calculatednoparseโ disable AVParsers, and this needs+nofillintoo, bestiesortdtsโ try to interleave output packets by DTS. at present, available only for AVIs with an index
Possible values for output files:
autobsfโ automatically apply bitstream filters as required by the output format. enabled by default โญbitexactโ only write platform-, build- and time-independent data. this ensures that file and data checksums are reproducible and match between platforms. its primary use is for regression testing ๐งชflush_packetsโ write out packets immediatelyshortestโ stop muxing at the end of the shortest stream. it may be needed to increasemax_interleave_deltato avoid flushing the longer streams before EOF
seek2any integer(input) โ allow seeking to non-keyframes on demuxer level when supported if set to1. default is0.analyzeduration integer(input) โ specify how many microseconds are analyzed to probe the input. a higher value enables detecting more accurate information, but increases latency. it defaults to5,000,000microseconds =5seconds โณcryptokey hexadecimal string(input) โ set decryption key ๐indexmem integer(input) โ set max memory used for timestamp index (per stream).rtbufsize integer(input) โ set max memory used for buffering real-time frames.fdebug flags(input/output) โ print specific debug info.
Possible values:
ts
max_delay integer(input/output) โ set maximum muxing or demuxing delay in microseconds.fpsprobesize integer(input) โ set number of frames used to probe fps.audio_preload integer(output) โ set microseconds by which audio packets should be interleaved earlier.chunk_duration integer(output) โ set microseconds for each chunk.chunk_size integer(output) โ set size in bytes for each chunk.err_detect,f_err_detect flags(input) โ set error detection flags. heads up:f_err_detectis deprecated and should be used only via the ffmpeg tool.
Possible values:
crccheckโ verify embedded CRCsbitstreamโ detect bitstream specification deviationsbufferโ detect improper bitstream lengthexplodeโ abort decoding on minor error detection ๐ฅcarefulโ consider things that violate the spec and have not been seen in the wild as errorscompliantโ consider all spec non compliancies as errorsaggressiveโ consider things that a sane encoder should not do as an error
max_interleave_delta integer(output) โ set maximum buffering duration for interleaving. the duration is expressed in microseconds, and defaults to10000000(10seconds).
so to ensure all the streams are interleaved correctly, libavformat will wait until it has at least one packet for each stream before actually writing any packets to the output file. when some streams are "sparse" (i.e. there are large gaps between successive packets), this can result in excessive buffering ๐ญ
this field specifies the maximum difference between the timestamps of the first and the last packet in the muxing queue, above which libavformat will output a packet regardless of whether it has queued a packet for all the streams.
if set to 0, libavformat will continue buffering packets until it has a packet for each stream, regardless of the maximum timestamp difference between the buffered packets.
use_wallclock_as_timestamps integer(input) โ use wallclock as timestamps if set to1. default is0.avoid_negative_ts integer(output) โ Possible values:make_non_negativeโ shift timestamps to make them non-negative. also note that this affects only leading negative timestamps, and not non-monotonic negative timestamps ๐make_zeroโ shift timestamps so that the first timestamp is0auto(default) โ enables shifting when required by the target formatdisabledโ disables shifting of timestamp
when shifting is enabled, all output timestamps are shifted by the same amount. audio, video, and subtitles desynching and relative timestamp differences are preserved compared to how they would have been without shifting ๐ซถ
skip_initial_bytes integer(input) โ set number of bytes to skip before reading header and frames if set to1. default is0.correct_ts_overflow integer(input) โ correct single timestamp overflows if set to1. default is1.flush_packets integer(output) โ flush the underlying I/O stream after each packet. default is-1(auto), which means that the underlying protocol will decide,1enables it, and has the effect of reducing the latency,0disables it and may increase IO throughput in some cases โจoutput_ts_offset offset(output) โ set the output time offset.
offset must be a time duration specification, see the Time duration section in the ffmpeg-utils(1) manual ๐
the offset is added by the muxer to the output timestamps.
specifying a positive offset means that the corresponding streams are delayed by the time duration specified in offset. default value is 0 (meaning that no offset is applied).
ngl there's a small typo in the original here ("delayed bt") โ it 100% means delayed by, bestie ๐
format_whitelist list(input) โ","separated list of allowed demuxers. by default all are allowed.dump_separator string(input) โ separator used to separate the fields printed on the command line about the Stream parameters. for example, to separate the fields with newlines and indentation:
ffprobe -dump_separator "
" -i ~/videos/matrixbench_mpeg2.mpg
max_streams integer(input) โ specifies the maximum number of streams. this can be used to reject files that would require too many resources due to a large number of streams ๐ซskip_estimate_duration_from_pts bool(input) โ skip estimation of input duration if it requires an additional probing for PTS at end of file. at present, applicable for MPEG-PS and MPEG-TS.duration_probesize integer(input) โ set probing size, in bytes, for input duration estimation when it actually requires an additional probing for PTS at end of file (at present: MPEG-PS and MPEG-TS). it's aimed at users interested in better durations probing for itself, or indirectly because using the concat demuxer, for example. the typical use case is an MPEG-TS CBR with a high bitrate, high video buffering and ending cleaning with similar PTS for video and audio: in such a scenario, the large physical gap between the last video packet and the last audio packet makes it necessary to read many bytes in order to get the video stream duration. another use case is where the default probing behaviour only reaches a single video frame which is not the last one of the stream due to frame reordering, so the duration is not accurate. setting this option has a performance impact even for small files because the probing size is fixed. default behaviour is a general purpose trade-off, largely adaptive, but the probing size will not be extended to get streams durations at all costs. must be an integer not lesser than1, or0for default behaviour ๐ฆstrict,f_strict integer(input/output) โ specify how strictly to follow the standards.f_strictis deprecated and should be used only via the ffmpeg tool.
Possible values:
veryโ strictly conform to an older more strict version of the spec or reference softwarestrictโ strictly conform to all the things in the spec no matter what consequencesnormalunofficialโ allow unofficial extensionsexperimentalโ allow non standardized experimental things, experimental (unfinished/work in progress/not well tested) decoders and encoders.
โ ๏ธ note: experimental decoders can pose a security risk, do not use this for decoding untrusted input. like, fr fr, don't ๐
๐ Format stream specifiers ๐
format stream specifiers let you select one or more streams that match specific properties ๐
the exact semantics of stream specifiers is defined by the avformat_match_stream_specifier() function declared in the libavformat/avformat.h header and documented in the Stream specifiers section in the ffmpeg(1) manual. go read it, bestie, it's giving essential lore ๐
๐ธ DEMUXERS ๐ธ
demuxers are configured elements in FFmpeg that can read the multimedia streams from a particular type of file โจ like, each one is a lil specialist for its own file type, and honestly? iconic behaviour ๐ซถ
okay so bestie, when you configure your FFmpeg build, every single supported demuxer is enabled by default โ yes, all of them, the whole squad. You can list every available one with the configure option --list-demuxers. ๐
And when you want to flip the switch the other way? You can nuke all the demuxers with the configure option --disable-demuxers, and then selectively enable exactly one with --enable-demuxer=DEMUXER, or disable just one with --disable-demuxer=DEMUXER. Cherry-picking queen behavior. ๐
The -demuxers option of the ff* tools will show you the list of enabled demuxers. And if you want the combined deluxe view โ enabled demuxers and muxers together โ use -formats. Two lists, one flex. โจ
The description of some of the currently available demuxers follows. Buckle up, it's giving buffet. ๐
aa
Audible Format 2, 3, and 4 demuxer.
This demuxer is the one you call when you need to demux Audible Format 2, 3, and 4 (.aa) files. Audiobook girlies stay winning. ๐ง
aac
Raw Audio Data Transport Stream AAC demuxer.
This demuxer is used to demux an ADTS input that contains a single AAC stream, along with any ID3v1/2 or APE tags sitting inside it. Tags and audio, holding hands. ๐ซถ
apng
Animated Portable Network Graphics demuxer.
This demuxer is used to demux APNG files. Here's the tea: all headers, but the PNG signature, up to (but not including) the first fcTL chunk, are transmitted as extradata. Frames then get split as being all the chunks between two fcTL ones, or between the last fcTL and IEND chunks. Slice it like a cake. ๐
-ignore_loopbool โ ignore the loop variable in the file if it's set. Default is enabled.-max_fpsint โ maximum framerate in frames per second. The default of0imposes no limit at all, go wild.-default_fpsint โ default framerate in frames per second when none is specified in the file (0meaning as fast as possible). Default is15.
asf
Advanced Systems Format demuxer.
This demuxer is used to demux ASF files and MMS network streams. Versatile icon. โญ
-no_resync_searchbool โ do not try to resynchronize by looking for a certain optional start code.
concat
Virtual concatenation script demuxer.
This demuxer reads a list of files and other directives from a text file, then demuxes them one after the other โ as if all their packets had been muxed together in the first place. It's giving "one long file, but make it a group project." ๐
The timestamps in the files get adjusted so that the first file starts at 0 and each next file starts exactly where the previous one finishes. Heads up though: this is done globally and may cause gaps if all streams do not have exactly the same length. No cap.
All files must have the same streams (same codecs, same time base, etc.). Every single one. No exceptions, bestie.
The duration of each file is used to adjust the timestamps of the next file: if the duration is incorrect (because it was computed using the bit-rate, or because the file is truncated, for example), it can cause artifacts. The duration directive exists so you can override the duration stored in each file. ๐
Syntax
The script is a text file in extended-ASCII, with one directive per line. Empty lines, leading spaces and lines starting with # are ignored. The following directive is recognized:
file pathโ path to a file to read; special characters and spaces must be escaped with backslash or single quotes. All subsequent file-related directives apply to that file.ffconcat version 1.0โ identify the script type and version. To make FFmpeg recognize the format automatically, this directive must appear exactly as is (no extra space or byte-order-mark) on the very first line of the script. First line. Not second. Not "close enough." ๐duration durโ duration of the file. This information can be specified from the file; specifying it here may be more efficient, or help if the information from the file isn't available or isn't accurate. If the duration is set for all files, then it is possible to seek in the whole concatenated video. Iconic.inpoint timestampโ In point of the file. When the demuxer opens the file it instantly seeks to the specified timestamp. Seeking is done so that all streams can be presented successfully at In point. This directive works best with intra frame codecs, because for non-intra frame ones you will usually get extra packets before the actual In point, and the decoded content will most likely contain frames before In point too. For each file, packets before the file In point will have timestamps less than the calculated start timestamp of the file (negative in case of the first file), and the duration of the files (if not specified by thedurationdirective) will be reduced based on their specified In point. Because of potential packets before the specified In point, packet timestamps may overlap between two concatenated files. Watch out for that overlap drama. ๐outpoint timestampโ Out point of the file. When the demuxer reaches the specified decoding timestamp in any of the streams, it handles it as an end of file condition and skips the current and all the remaining packets from all streams. Out point is exclusive, which means the demuxer will not output packets with a decoding timestamp greater or equal to Out point. This directive works best with intra frame codecs and formats where all streams are tightly interleaved. For non-intra frame codecs you will usually get additional packets with presentation timestamp after Out point, therefore the decoded content will most likely contain frames after Out point too. If your streams are not tightly interleaved you may not get all the packets from all streams before Out point, and you may only will be able to decode the earliest stream until Out point. The duration of the files (if not specified by thedurationdirective) will be reduced based on their specified Out point.file_packet_metadata key=valueโ metadata of the packets of the file. The specified metadata will be set for each file packet. You can specify this directive multiple times to add multiple metadata entries. This directive is deprecated โ usefile_packet_metainstead. She's retired but still on the payroll. ๐file_packet_meta key valueโ metadata of the packets of the file. The specified metadata will be set for each file packet. You can specify this directive multiple times to add multiple metadata entries.option key valueโ option to access, open and probe the file. Can be present multiple times.streamโ introduce a stream in the virtual file. All subsequent stream-related directives apply to the last introduced stream. Some streams properties must be set in order to allow identifying the matching streams in the subfiles. If no streams are defined in the script, the streams from the first file are copied.exact_stream_id idโ set the id of the stream. If this directive is given, the string with the corresponding id in the subfiles will be used. This is especially useful for MPEG-PS (VOB) files, where the order of the streams is not reliable. Trust issues, honestly. ๐ญstream_meta key valueโ metadata for the stream. Can be present multiple times.stream_codec valueโ codec for the stream.stream_extradata hex_stringโ extradata for the string, encoded in hexadecimal.chapter id start endโ add a chapter.idis an unique identifier, possibly small and consecutive.
Options
This demuxer accepts the following option:
safeโ if set to1, reject unsafe file paths and directives. A file path is considered safe if it does not contain a protocol specification and is relative and all components only contain characters from the portable character set (letters, digits, period, underscore and hyphen) and have no period at the beginning of a component. If set to0, any file name is accepted. The default is1. Keep this on unless you know exactly what you're doing, bestie. ๐ฅauto_convertโ if set to1, try to perform automatic conversions on packet data to make the streams concatenable. The default is1. Currently, the only conversion is adding theh264_mp4toannexbbitstream filter to H.264 streams in MP4 format. This is necessary in particular if there are resolution changes.segment_time_metadataโ if set to1, every packet will contain thelavf.concat.start_timeand thelavf.concat.durationpacket metadata values, which are thestart_timeand the duration of the respective file segments in the concatenated output expressed in microseconds. The duration metadata is only set if it is known based on the concat file. The default is0.
Examples
- Use absolute filenames and include some comments:
# my first filename
file /mnt/share/file-1.wav
# my second filename including whitespace
file '/mnt/share/file 2.wav'
# my third filename including whitespace plus single quote
file '/mnt/share/file 3'\''.wav'
- Allow for input format auto-probing, use safe filenames and set the duration of the first file:
ffconcat version 1.0
file file-1.wav
duration 20.0
file subdir/file-2.wav
dash
Dynamic Adaptive Streaming over HTTP demuxer.
This demuxer presents all AVStreams found in the manifest. By setting the discard flags on AVStreams the caller can decide which streams to actually receive. Each stream mirrors the id and bandwidth properties from the <Representation> as metadata keys named id and variant_bitrate respectively. Mirror mirror on the wall. ๐ช
Options
This demuxer accepts the following option:
cenc_decryption_keyโ default 16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7).cenc_decryption_keysโ dictionary of 16-byte key ID => 16-byte key, both in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7).
dvdvideo
DVD-Video demuxer, powered by libdvdnav and libdvdread.
Can directly ingest DVD titles โ specifically sequential PGCs โ into a conversion pipeline. Menu assets, such as background video or audio, can also be demuxed given the menu's coordinates (at best effort). Best effort is still effort, okay? ๐
Block devices (DVD drives), ISO files, and directory structures are accepted. Activate with -f dvdvideo in front of one of these inputs.
โ ๏ธ This demuxer does NOT have decryption code of any kind. You are on your own working with encrypted DVDs, and should not expect support on the matter. Like, genuinely โ none. ๐
Underlying playback is handled by libdvdnav, and structure parsing by libdvdread. FFmpeg must be built with GPL library support available as well as the configure switches --enable-libdvdnav and --enable-libdvdread. โจ
You're gonna need either the "title number" you want or the exact PGC/PG coordinates. Tons of open-source DVD players and tools can help you hunt that info down. If you don't specify anything, the demuxer just defaults to title 1, which lowkey works for a lot of discs โ but honestly, because this format is so flexible, bestie, please check manually. There are so many discs out there authored weirdly or with straight-up invalid headers. ๐
If your input is an actual real DVD drive, heads up: some drives will silently fail when reading bad sectors and just hand you random bits instead, which is effectively corrupt data. This is especially prominent on aging or rotting discs. You'd need a second pass plus integrity checks to even detect that corruption. And like โ this is not an FFmpeg issue, okay? Not our problem, not our fault. ๐
Background
DVD-Video is not a directly accessible, linear container format in the traditional sense. Nope! Instead it lets you do complex, programmatic playback of carefully muxed MPEG-PS streams stored in headerless VOB files. To the end-user these streams are just known as "titles", but the actual logical playback sequence is defined by one or more "PGCs" โ Program Group Chains โ inside the title. The PGC is in turn made of multiple "PGs", or "Programs", which are the actual video segments (and for a typical video feature, they're sequentially ordered). The PGC structure, along with stream layout and metadata, lives in IFO files that need to be parsed. Easiest way to think about it: PGCs are basically playlists. ๐
A real DVD player relies on user GUI interaction via menus and an internal VM to drive the direction of demuxing. Usually the user either navigates via menus or gets automatically redirected to the PGC of their choice. During that whole process and the playback after it, the DVD player's internal VM also maintains a state and executes instructions that can create jumps to different sectors mid-playback. That's literally why libdvdnav is involved โ a linear read of the MPEG-PS blobs on the disc (the VOBs) is just not enough to produce the right sequence in many cases. Periodt.
There are many other DVD structures (a whole long subject, seriously) that won't be discussed here. NAV packets in particular are handled by this demuxer to build accurate timing, but they are not emitted as a stream. For a good high-level understanding, go read: https://code.videolan.org/videolan/libdvdnav/-/blob/master/doc/dvd_structures
Options
This demuxer accepts the following options:
titleint โ the title number to play. Must be set ifpgcandpgare not set. Not applicable to menus. Default is0(auto), which currently only selects the first available title (title 1) and notifies the user about the implications. ๐chapter_startint โ the chapter, or PTT (part-of-title), number to start at. Not applicable to menus. Default is1.chapter_endint โ the chapter, or PTT (part-of-title), number to end at. Not applicable to menus. Default is0, which is a special value meaning "end at the last possible chapter". ๐angleint โ the video angle number, which refers to what's essentially an additional video stream composed from alternate frames interleaved in the VOBs. Not applicable to menus. Default is1.regionint โ the region code to use for playback. Some discs may use this to default playback to a particular angle in different regions. This option will not affect the region code of a real DVD drive if one is used as input. Not applicable to menus. Default is0, "world". ๐menubool โ demux menu assets instead of navigating a title. Requires the exact coordinates of the menu (menu_lu,menu_vts,pgc,pg). Default isfalse.menu_luint โ the menu language to demux. In DVD, menus are grouped by language. Default is1, the first language unit.menu_vtsint โ the VTS where the menu lives, or0if it's a VMG menu (root-level). Default is1, the menu of the first VTS.pgcint โ the entry PGC to start playback, in conjunction withpg. An alternative to settingtitle. Chapter markers are not supported at this time. Must be explicitly set for menus. Default is0, automatically resolved from the value oftitle.pgint โ the entry PG to start playback, in conjunction withpgc. An alternative to settingtitle. Chapter markers are not supported at this time. Default is1, the first PG of the PGC.preindexbool โ enable this to get accurate chapter (PTT) markers and duration measurement, which requires a slow second-pass read in order to index the chapter marker timestamps from NAV packets. That's non-ideal extra work for real optical drives ๐ญ โ it's recommended and faster to use this option with a backup of the DVD structure stored on a hard drive. Not compatible withpgcandpg. Default is0,false.trimbool โ skip padding cells (i.e. cells shorter than 1 second) from the beginning. There are many discs with filler segments at the start of the PGC, often full of junk data intended to control a real DVD player's buffering speed, with no other materially useful value whatsoever. Not applicable to menus. Default is1,true.
Examples
- Open title 3 from a given DVD structure:
ffmpeg -f dvdvideo -title 3 -i <path to DVD> ...
- Open chapters 3-6 from title 1 from a given DVD structure:
ffmpeg -f dvdvideo -chapter_start 3 -chapter_end 6 -title 1 -i <path to DVD> ...
- Open only chapter 5 from title 1 from a given DVD structure:
ffmpeg -f dvdvideo -chapter_start 5 -chapter_end 5 -title 1 -i <path to DVD> ...
- Demux menu with language 1 from VTS 1, PGC 1, starting at PG 1:
ffmpeg -f dvdvideo -menu 1 -menu_lu 1 -menu_vts 1 -pgc 1 -pg 1 -i <path to DVD> ...
๐ ea
Electronic Arts Multimedia format demuxer. This format is used by various Electronic Arts games. ๐ฎ
Options
merge_alphabool โ normally the VP6 alpha channel (if it exists) is returned as a secondary video stream. By setting this option you can make the demuxer return a single video stream that contains the alpha channel in addition to the ordinary video. Slay.
โจ imf
Interoperable Master Format demuxer.
This demuxer presents the audio and video streams found in an IMF Composition, as specified in https://doi.org/10.5594/SMPTE.ST2067-2.2020.
ffmpeg [-assetmaps <path of ASSETMAP1>,<path of ASSETMAP2>,...] -i <path of CPL> ...
If -assetmaps is not specified, the demuxer looks for a file called ASSETMAP.xml in the same directory as the CPL. ๐
๐ฆ flv, live_flv, kux
Adobe Flash Video Format demuxer.
This demuxer is used to demux FLV files and RTMP network streams. For live network streams, if you force the format you may use the live_flv option instead of flv to survive timestamp discontinuities. KUX is an flv variant used on the Youku platform.
ffmpeg -f flv -i myfile.flv ...
ffmpeg -f live_flv -i rtmp://<any.server>/anything/key ....
-flv_metadatabool โ allocate the streams according to theonMetaDataarray content.-flv_ignore_prevtagbool โ ignore the size of previous tag value.-flv_full_metadatabool โ output all context of theonMetadata.
๐ gif
Animated GIF demuxer. It accepts the following options:
min_delayโ set the minimum valid delay between frames, in hundredths of seconds. Range is0to6000. Default value is2.max_gif_delayโ set the maximum valid delay between frames, in hundredths of seconds. Range is0to65535. Default value is65535(nearly eleven minutes), which is the maximum value allowed by the specification.default_delayโ set the default delay between frames, in hundredths of seconds. Range is0to6000. Default value is10.ignore_loopโ GIF files can contain info to loop a certain number of times (or infinitely). Ifignore_loopis set to1, then the loop setting from the input will be ignored and looping will not occur. If set to0, then looping will occur and will cycle the number of times according to the GIF. Default value is1.
For example, with the overlay filter, place an infinitely looping GIF over another video:
ffmpeg -i input.mp4 -ignore_loop 0 -i input.gif -filter_complex overlay=shortest=1 out.mkv
Note that in the above example the shortest option for the overlay filter is used to end the output video at the length of the shortest input file โ which in this case is input.mp4, since the GIF in this example loops infinitely. ๐๏ธ
๐ hls
HLS demuxer.
Apple HTTP Live Streaming demuxer.
This demuxer presents all AVStreams from all variant streams. The id field is set to the bitrate variant index number. By setting the discard flags on AVStreams (by pressing a or v in ffplay), the caller can decide which variant streams to actually receive. The total bitrate of the variant that the stream belongs to is available in a metadata key named variant_bitrate.
It accepts the following options:
live_start_indexโ segment index to start live streams at (negative values are from the end).prefer_x_startโ prefer to use#EXT-X-STARTif it's in the playlist, instead oflive_start_index.allowed_extensionsโ','-separated list of file extensions that hls is allowed to access.extension_pickyโ this blocks disallowed extensions from probing. It also requires all available segments to have matching extensions to the format, except mpegts, which is always allowed. It's recommended to set the whitelists correctly instead of depending on extensions. Enabled by default.max_reloadโ maximum number of times an insufficient list is attempted to be reloaded. Default value is1000.m3u8_hold_countersโ the maximum number of times to load m3u8 when it refreshes without new segments. Default value is1000.http_persistentโ use persistent HTTP connections. Applicable only for HTTP streams. Enabled by default.http_multipleโ use multiple HTTP connections for downloading HTTP segments. Enabled by default for HTTP/1.1 servers.http_seekableโ use HTTP partial requests for downloading HTTP segments.0= disable,1= enable,-1= auto, Default is auto.seg_format_optionsโ set options for the demuxer of media segments using a list ofkey=valuepairs separated by":".seg_max_retryโ maximum number of times to reload a segment on error, useful when segment skip on network error is not desired. Default value is0.
๐ง image2
Image file demuxer.
so this demuxer is out here reading from a whole list of image files that you hand it via a pattern ๐ The syntax and the meaning of that pattern is specified by the option pattern_type.
The pattern can carry a suffix, and that suffix is what's used to automatically figure out the format of the images sitting inside the files.
Big rule, no exceptions: the size, the pixel format, and the format of each image must be the same for all the files in the sequence. all of them. same. or it's not gonna slay ๐
This demuxer accepts the following options:
framerateโ sets the frame rate for the video stream. defaults to25.loopโ if you set it to1, it loops over the input. default value is0.pattern_typeโ selects which pattern type is used to interpret the filename you provided. it accepts one of these values:noneโ disables pattern matching, so the video will only contain the specified image. use this one if you don't want to create sequences from multiple images and your filenames might contain special pattern characters.sequenceโ selects a sequence pattern type, used to specify a sequence of files indexed by sequential numbers.- a sequence pattern may contain the string
%dor%0Nd, which specifies the position of the characters representing a sequential number in each filename matched by the pattern. - if the form
%d0Ndis used, the string representing the number in each filename is 0-padded, andNis the total number of 0-padded digits representing the number. - the literal character
%can be specified in the pattern with the string%%. - if the sequence pattern contains
%dor%0Nd, the first filename of the file list specified by the pattern must contain a number that's inclusively contained betweenstart_numberandstart_number+start_number_range-1, and all the following numbers must be sequential. no skipping, bestie ๐ - for example, the pattern
img-%03d.bmpwill match a sequence of filenames of the formimg-001.bmp,img-002.bmp, ...,img-010.bmp, etc.; the patterni%%m%%g-%d.jpgwill match a sequence of filenames of the formi%m%g-1.jpg,i%m%g-2.jpg, ...,i%m%g-10.jpg, etc. - note that the pattern doesn't necessarily have to contain
%dor%0Ndโ for example, to convert a single image fileimg.jpegyou can employ the command:ffmpeg -i img.jpeg img.png
- a sequence pattern may contain the string
globโ selects a glob wildcard pattern type. the pattern is interpreted like aglob()pattern. this is only selectable if libavformat was compiled with globbing support.- default value is
sequence. โจ
pixel_formatโ sets the pixel format of the images to read. if you don't specify it, the pixel format gets guessed from the first image file in the sequence.start_numberโ sets the index of the file matched by the image file pattern where reading starts. default value is0.start_number_rangeโ sets the index interval range to check when looking for the first image file in the sequence, starting fromstart_number. default value is5.ts_from_fileโ if set to1, it will set the frame timestamp to the modification time of the image file. note that monotonity of timestamps is not provided: images go in the same order as without this option. default value is0. if set to2, it will set the frame timestamp to the modification time of the image file in nanosecond precision. ๐ฐ๏ธvideo_sizeโ sets the video size of the images to read. if not specified, the video size gets guessed from the first image file in the sequence.export_path_metadataโ if set to1, it will add two extra fields to the metadata found in input, making them also available for other filters (seedrawtextfilter for examples). default value is0. the extra fields are described below:lavf.image2dec.source_pathโ corresponds to the full path to the input file being read.lavf.image2dec.source_basenameโ corresponds to the name of the file being read.
Examples ๐
- use
ffmpegfor creating a video from the images in the file sequenceimg-001.jpeg,img-002.jpeg, ..., assuming an input frame rate of 10 frames per second:
ffmpeg -framerate 10 -i 'img-%03d.jpeg' out.mkv
- as above, but start by reading from a file with index
100in the sequence:
ffmpeg -framerate 10 -start_number 100 -i 'img-%03d.jpeg' out.mkv
- read images matching the
*.pngglob pattern, that is all the files terminating with the.pngsuffix:
ffmpeg -framerate 10 -pattern_type glob -i "*.png" out.mkv
๐ฎ libgme โจ
the Game Music Emu library is a collection of video game music file emulators. it's giving retro arcade realness ๐
see https://bitbucket.org/mpyne/game-music-emu/overview for more information.
it accepts the following options:
track_indexโ sets the index of which track to demux. the demuxer can only export one track (sorry, greedy). track indexes start at0. default is to pick the first track. the number of tracks is exported as thetracksmetadata entry.sample_rateโ sets the sampling rate of the exported track. range is1000to999999. default is44100.max_size(bytes) โ the demuxer buffers the entire file into memory, ngl. adjust this value to set the maximum buffer size, which in turn acts as a ceiling for the size of files that can be read. default is50 MiB.
๐น libmodplug ๐
ModPlug based module demuxer ๐ถ
see https://github.com/Konstanty/libmodplug
it will export one 2-channel 16-bit 44.1 kHz audio stream. optionally, a pal8 16-color video stream can be exported with or without printed metadata. so you can have your tracker bops and your little rainbow visuals ๐
it accepts the following options:
noise_reductionโ applies a simple low-pass filter. can be1(on) or0(off). default is0.reverb_depthโ sets the amount of reverb. range0-100. default is0.reverb_delayโ sets the delay in ms, clamped to40-250ms. default is0.bass_amountโ applies bass expansion a.k.a. XBass or megabass. range is0(quiet) to100(loud). default is0. turn it up fr fr ๐bass_rangeโ sets the cutoff, i.e. the upper-bound for bass frequencies. range is10-100Hz. default is0.surround_depthโ applies a Dolby Pro-Logic surround effect. range is0(quiet) to100(heavy). default is0.surround_delayโ sets the surround delay in ms, clamped to5-40ms. default is0.max_sizeโ the demuxer buffers the entire file into memory. adjust this value to set the maximum buffer size, which in turn acts as a ceiling for the size of files that can be read. range is0to100 MiB.0removes the buffer size limit (not recommended ๐). default is5 MiB.video_stream_exprโ a string which is evaluated using theevalAPI to assign colors to the generated video stream. variables which can be used arex,y,w,h,t,speed,tempo,order,patternandrow.video_streamโ generates the video stream. can be1(on) or0(off). default is0.video_stream_wโ sets the video frame width in 'chars' where one char indicates 8 pixels. range20-512. default is30.video_stream_hโ sets the video frame height in 'chars' where one char indicates 8 pixels. range20-512. default is30.video_stream_ptxtโ prints metadata on the video stream. includesspeed,tempo,order,pattern,rowandts(time in ms). can be1(on) or0(off). default is1.
๐ผ libopenmpt ๐ฆ
libopenmpt based module demuxer โจ
see https://lib.openmpt.org/libopenmpt/ for more information.
some files have multiple subsongs (tracks), and you can set that with the subsong option.
it accepts the following options:
subsongโ sets the subsong index. this can be either'all','auto', or the index of the subsong. subsong indexes start at0. the default is'auto'. the default value is to let libopenmpt choose ๐layoutโ sets the channel layout. valid values are1,2, and4channel layouts. the default value isSTEREO.sample_rateโ sets the sample rate for libopenmpt to output. range is from1000toINT_MAX. the value default is48000.
๐ฌ mcc ๐
demuxer for MacCaption MCC files โ it supports MCC versions 1.0 and 2.0. MCC files store VANC data, which can include closed captions (EIA-608 and CEA-708), ancillary time code, pan-scan data, etc. by default, for backward compatibility, the MCC demuxer extracts just the EIA-608 and CEA-708 closed captions and returns a EIA_608 stream, ignoring all other VANC data. you can change it to return all VANC data in a SMPTE_436M_ANC data stream by setting -eia608_extract 0 ๐ซถ
Examples ๐
- convert a MCC file to Scenarist (SCC) format:
ffmpeg -i CC.mcc -c:s copy CC.scc
note that the SCC format only supports EIA-608, so this will discard all other data such as CEA-708 extensions. ๐ญ
- merge a MCC file into a MXF file:
ffmpeg -i video_and_audio.mxf -eia608_extract 0 -i CC.mcc -c copy -map 0 -map 1 out.mxf
this retains all VANC data and inserts it into the output MXF file as a SMPTE_436M_ANC data stream. ๐
๐ฅ mov/mp4/3gp ๐
demuxer for Quicktime File Format & ISO/IEC Base Media File Format (ISO/IEC 14496-12 or MPEG-4 Part 12, ISO/IEC 15444-12 or JPEG 2000 Part 12).
registered extensions: mov, mp4, m4a, 3gp, 3g2, mj2, psp, m4b, ism, ismv, isma, f4v
Options ๐
this demuxer accepts the following options:
enable_drefsโ enables loading of external tracks, disabled by default. enabling this can theoretically leak information in some use cases ๐ฌuse_absolute_pathโ allows loading of external tracks via absolute paths, disabled by default. enabling this poses a security risk. it should only be enabled if the source is known to be non-malicious. like, known known. do not play yourself ๐seek_streams_individuallyโ when seeking, it identifies the closest point in each stream individually and demuxes packets in that stream from the identified point. this can lead to a different sequence of packets compared to demuxing linearly from the beginning. default istrue.ignore_editlistโ ignores any edit list atoms. the demuxer, by default, modifies the stream index to reflect the timeline described by the edit list. default isfalse.advanced_editlistโ modifies the stream index to reflect the timeline described by the edit list.ignore_editlistmust be set tofalsefor this option to be effective. if bothignore_editlistand this option are set tofalse, then only the start of the stream index is modified to reflect initial dwell time or starting timestamp described by the edit list. default istrue.ignore_chaptersโ bestie, just don't parse the chapters. That includes GoPro 'HiLight' tags/moments, so those little highlight moments get skipped too. Heads up tho: chapters only get parsed when the input is seekable. Default isfalse.use_mfra_forโ for seekable fragmented input, this sets the fragment's starting timestamp from the media fragment random access box โ but only if it's actually there. The options are giving:autoโ auto-detect whether to set mfra timestamps as PTS or DTS (default)dtsโ set mfra timestamps as DTSptsโ set mfra timestamps as PTS0โ don't use the mfra box to set timestamps at all
use_tfdtโ for fragmented input, set the fragment's starting timestamp to"baseMediaDecodeTime"from the"tfdt"box. Default is enabled, which prefers using the"tfdt"box to set DTS. Disable it and it'll use the"earliest_presentation_time"from the"sidx"box instead. Either way, the timestamp from the"mfra"box gets used if it's available and"use_mfra_for"is set toptsordts. โจexport_allโ export unrecognized boxes inside the udta box as metadata entries. The first four characters of the box type become the key. Default isfalse.export_xmpโ export the entire contents of the XMP_ box and uuid box as a string with the key"xmp". Small lil gotcha: if"export_all"is set and this option isn't, the contents of the XMP_ box still get exported โ just under the key"XMP_"instead. Default isfalse.activation_bytesโ the 4-byte key you need to decrypt Audible AAX and AAX+ files. Peep the Audible AAX subsection below ๐audible_fixed_keyโ a fixed key used for handling Audible AAX/AAX+ files. It's already been pre-set, so you shouldn't need to specify it. It's handled, bestie ๐decryption_keyโ default 16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7).decryption_keysโ a dictionary of 16-byte key ID => 16-byte key (both in hex, bestie) to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7).max_stts_deltaโ okay so very high sample deltas written in a trak's stts box might occasionally be intentional, but usually they're written in error, or they're being used to store a negative value for dts correction when treated as signed 32-bit integers. This option lets you set an upper limit โ anything beyond it gets clamped to 1. Values greater than the limit, if negative when cast to int32, are used to adjust onward dts.
The unit is the track time scale. Range is 0 to UINT_MAX. Default is "UINT_MAX - 48000*10", which allows up to a 10 second dts correction for 48 kHz audio streams while still accommodating 99.9% of "uint32" range. Math slay ๐ฅ
interleaved_readโ interleave packets from multiple tracks at demuxer level. For badly interleaved files, this prevents playback issues caused by large gaps between packets in different tracks, because MOV/MP4 genuinely do not have packet placement requirements. However โ and this is a real one โ it can cause excessive seeking on very badly interleaved files, since it's seeking between tracks. So disabling it may prevent I/O issues, at the expense of playback. Pick your struggle ๐ซ
๐ง Audible AAX ๐ง
Audible AAX files are encrypted M4B files, and you can decrypt them by specifying a 4 byte activation secret. Literally that's it:
ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
๐ mpegts ๐
MPEG-2 transport stream demuxer. This demuxer accepts the following options:
resync_sizeโ set the size limit for looking up a new synchronization. Default value is65536.skip_unknown_pmtโ skip PMTs for programs not defined in the PAT. Default value is0.fix_teletext_ptsโ override teletext packet PTS and DTS values with the timestamps calculated from the PCR of the first program which the teletext stream is part of and is not discarded. Default value is1. Set this option to0if you want your teletext packet PTS and DTS values left untouched, periodt.ts_packetsizeโ output option carrying the raw packet size in bytes. It shows the detected raw packet size โ and no, you can't set it yourself, the user has no power here ๐scan_all_pmtsโ scan and combine all PMTs. Value is an integer from-1to1(-1means automatic setting,1means enabled,0means disabled). Default value is-1.merge_pmt_versionsโ reuse existing streams when a PMT's version is updated and elementary streams move to different PIDs. Default value is0.max_packet_sizeโ set the maximum size, in bytes, of the packet emitted by the demuxer. Payloads above this size get split across multiple packets. Range is184toINT_MAX/2. Default is204800bytes.
๐ผ๏ธ mpjpeg ๐ผ๏ธ
MJPEG encapsulated in multi-part MIME demuxer. This demuxer lets you read MJPEG where each frame is represented as a part of a multipart/x-mixed-replace stream. Cute.
strict_mime_boundaryโ the default implementation applies a relaxed standard to multi-part MIME boundary detection, to prevent regression with the numerous existing endpoints that aren't generating a proper MIME MJPEG stream. Turning this option on by setting it to1gives you a stricter check of the boundary value. Strict queen behavior ๐
๐ผ rawvideo ๐ผ
Raw video demuxer. This one lets you read raw video data. Since there's no header specifying the assumed video parameters, you have to specify them yourself so the data can be decoded correctly. No header, no hand-holding, you're the main character now.
This demuxer accepts the following options:
framerateโ set input video frame rate. Default value is25.pixel_formatโ set the input video pixel format. Default value is"yuv420p".strideโ set frame line size in bytes; only required if there's extra padding. For multiplane formats, stride is a list of line size for each plane.video_sizeโ set the input video size. This value must be specified explicitly. No default, no vibes-based guessing.
So like, to read a rawvideo file input.raw with ffplay, assuming a pixel format of "rgb24", a video size of "320x240", and a frame rate of 10 images per second, you'd run:
ffplay -f rawvideo -pixel_format rgb24 -video_size 320x240 -framerate 10 input.raw
And to read a rawvideo with ffplay, assuming a pixel format of "yuv420p", a video size of "1080x1920", 8 bytes of padding in each line of the Y plane, and 4 bytes of padding with the UV plane:
ffplay -f rawvideo -pixel_format yuv420p -video_size 1080x1920 -stride 1088,544,544 input.raw
๐ฌ rcwt ๐ฌ
RCWT (Raw Captions With Time) is a format native to ccextractor, a commonly used open source tool for processing 608/708 Closed Captions (CC) sources. For more information on the format, see . (Yep, the manpage literally just ends there with a period โ that's all the tea we get ๐)
This demuxer implements the specification as of March 2024, which has been stable and unchanged since April 2014. Iconic longevity honestly.
๐ธ Examples ๐ธ
- Render CC to ASS using the built-in decoder:
ffmpeg -i CC.rcwt.bin CC.ass
Quick note bestie: if your output looks empty, you may have to manually set the decoder's data_field option to pick the desired CC substream. Don't panic, it's not broken, it's just shy.
- Convert an RCWT backup to Scenarist (SCC) format:
ffmpeg -i CC.rcwt.bin -c:s copy CC.scc
Heads up tho: the SCC format does not support all of the possible CC extensions that can be stored in RCWT (such as EIA-708). So some of that data just doesn't make the trip ๐ญ
๐ง sbg ๐ง
SBaGen script demuxer. This demuxer reads the script language used by SBaGen <http://uazu.net/sbagen/> to generate binaural beats sessions. A SBG script looks like this:
-SE
a: 300-2.5/3 440+4.5/0
b: 300-2.5/0 440+4.5/3
off: -
NOW == a
+0:07:00 == b
+0:14:00 == a
+0:21:00 == b
+0:30:00 off
Okay so a SBG script can mix absolute and relative timestamps. If the script uses either only absolute timestamps (including the script start time) or only relative ones, then its layout is fixed and the conversion is straightforward โ easy slay. But if the script mixes both kinds of timestamps, then the NOW reference for relative timestamps gets taken from the current time of day at the moment the script is read, and the script layout gets frozen according to that reference. What does that mean in practice? If the script is played directly, the actual times will match the absolute timestamps up to the sound controller's clock accuracy โ but if the user somehow pauses playback or seeks, all the times get shifted accordingly. Forewarned is forearmed โจ
๐ค tedcaptions ๐ค
JSON captions used for <http://www.ted.com/>. TED doesn't provide links to the captions, but they can be guessed from the page. The file tools/bookmarklets.html from the FFmpeg source tree contains a bookmarklet to expose them. Sneaky but effective ๐
This demuxer accepts the following option:
start_timeโ set the start time of the TED talk, in milliseconds. The default is15000(15s). It's used to sync the captions with the downloadable videos, because those include a 15s intro. Gotta account for the intro, periodt.
Example: convert the captions to a format most players understand:
ffmpeg -i http://www.ted.com/talks/subtitles/id/1/lang/en talk1-en.srt
๐ฆ vapoursynth ๐ฆ
Vapoursynth wrapper. Due to security concerns, Vapoursynth scripts will not be autodetected, so the input format has to be forced. For ff* CLI tools, add "-f vapoursynth" before the input "-i yourscript.vpy". Security girlies stay winning ๐
This demuxer accepts the following option:
max_script_sizeโ the demuxer buffers the entire script into memory. Adjust this value to set the maximum buffer size, which in turn acts as a ceiling for the size of scripts that can be read. Default is 1 MiB.
๐ w64 ๐
Sony Wave64 Audio demuxer. This demuxer accepts the following options:
max_sizeโ see the same option for the wav demuxer. (Yes, it's pointing at wav. Go look at wav. We're getting to wav. Patience bestie ๐)
๐ wav ๐
RIFF Wave Audio demuxer. This demuxer accepts the following options:
max_sizeโ specify the maximum packet size in bytes for the demuxed packets. By default this is set to0, which means a sensible value gets chosen based on the input format. Let the demuxer cook ๐ฅ
โจ METADATA โจ
Okay bestie, so FFmpeg can literally dump metadata from media files into a simple UTF-8-encoded INI-like text file and then load it right back using the metadata muxer/demuxer. It's giving "metadata glow-up" and honestly? Obsessed. ๐
The file format is as follows:
- A file consists of a header and a number of metadata tags divided into sections, each on its own line.
- The header is a
;FFMETADATAstring, followed by a version number (now1). - Metadata tags are of the form
key=value - Immediately after header follows global metadata
- After global metadata there may be sections with per-stream/per-chapter metadata.
- A section starts with the section name in uppercase (i.e.
STREAMorCHAPTER) in brackets ([,]) and ends with next section or end of file. - At the beginning of a chapter section there may be an optional timebase to be used for start/end values. It must be in form
TIMEBASE=num/den, wherenumanddenare integers. If the timebase is missing then start/end times are assumed to be in nanoseconds.
Next a chapter section must contain chapter start and end times in form START=num, END=num, where num is a positive integer.
- Empty lines and lines starting with
;or#are ignored. - Metadata keys or values containing special characters (
=,;,#,\and a newline) must be escaped with a backslash\. - Note that whitespace in metadata (e.g.
foo = bar) is considered to be a part of the tag (in the example above key isfoo, value isbar).
A ffmetadata file might look like this:
;FFMETADATA1
title=bike\\shed
;this is a comment
artist=FFmpeg troll team
[CHAPTER]
TIMEBASE=1/1000
START=0
#chapter ends at 0:01:00
END=60000
title=chapter \#1
[STREAM]
title=multi\
line
By using the ffmetadata muxer and demuxer it is possible to extract metadata from an input file to an ffmetadata file, and then transcode the file into an output file with the edited ffmetadata file. No cap, this is the metadata pipeline of all time. ๐
Extracting an ffmetadata file with ffmpeg goes as follows:
ffmpeg -i INPUT -f ffmetadata FFMETADATAFILE
Reinserting edited metadata information from the FFMETADATAFILE file can be done as:
ffmpeg -i INPUT -i FFMETADATAFILE -map_metadata 1 -codec copy OUTPUT
๐ PROTOCOL OPTIONS ๐
The libavformat library provides some generic global options, which can be set on all the protocols. In addition each protocol may support so-called private options, which are specific for that component. Very "main character energy, but make it configurable." โจ
Options may be set by specifying -option value in the FFmpeg tools, or by setting the value explicitly in the AVFormatContext options or using the libavutil/opt.h API for programmatic use.
The list of supported options follows:
protocol_whitelistlist (input) โ Set a,-separated list of allowed protocols.ALLmatches all protocols. Protocols prefixed by-are disabled. All protocols are allowed by default but protocols used by an another protocol (nested protocols) are restricted to a per protocol subset. ๐ซถ
๐ PROTOCOLS ๐
Protocols are configured elements in FFmpeg that enable access to resources that require specific protocols. They're lowkey the little doorways into all the data. ๐ชโจ
When you configure your FFmpeg build, all the supported protocols are enabled by default. You can list all available ones using the configure option --list-protocols.
You can disable all the protocols using the configure option --disable-protocols, and selectively enable a protocol using the option --enable-protocol=PROTOCOL, or you can disable a particular protocol using the option --disable-protocol=PROTOCOL. Choose your own protocol adventure, bestie. ๐ฆ
The option -protocols of the ff* tools will display the list of supported protocols.
All protocols accept the following options:
rw_timeoutโ Maximum time to wait for (network) read/write operations to complete, in microseconds. Literally "don't leave me hanging" energy. ๐ญ
A description of the currently available protocols follows.
amqp
Advanced Message Queueing Protocol (AMQP) version 0-9-1 is a broker based publish-subscribe communication protocol. It's giving "messages through the group chat, but enterprise." ๐ฌ
FFmpeg must be compiled with --enable-librabbitmq to support AMQP. A separate AMQP broker must also be run. An example open-source AMQP broker is RabbitMQ. ๐
After starting the broker, an FFmpeg client may stream data to the broker using the command:
ffmpeg -re -i input -f mpegts amqp://[[user]:[password]@]hostname[:port][/vhost]
Where hostname and port (default is 5672) is the address of the broker. The client may also set a user/password for authentication. The default for both fields is guest. Name of virtual host on broker can be set with vhost. The default value is /. Slay, defaults. ๐
Multiple subscribers may stream from the broker using the command:
ffplay amqp://[[user]:[password]@]hostname[:port][/vhost]
In RabbitMQ all data published to the broker flows through a specific exchange, and each subscribing client has an assigned queue/buffer. When a packet arrives at an exchange, it may be copied to a client's queue depending on the exchange and routing_key fields. That's the whole routing situation, fr fr. ๐
The following options are supported:
exchangeโ Sets the exchange to use on the broker. RabbitMQ has several predefined exchanges:amq.directis the default exchange, where the publisher and subscriber must have a matchingrouting_key;amq.fanoutis the same as a broadcast operation (i.e. the data is forwarded to all queues on the fanout exchange independent of therouting_key); andamq.topicis similar toamq.direct, but allows for more complex pattern matching (refer to the RabbitMQ documentation).routing_keyโ Sets the routing key. The default value isamqp. The routing key is used on theamq.directandamq.topicexchanges to decide whether packets are written to the queue of a subscriber.pkt_sizeโ Maximum size of each packet sent/received to the broker. Default is131072. Minimum is4096and max is any large value (representable by an int). When receiving packets, this sets an internal buffer size in FFmpeg. It should be equal to or greater than the size of the published packets to the broker. Otherwise the received message may be truncated causing decoding errors. โ ๏ธconnection_timeoutโ The timeout in seconds during the initial connection to the broker. The default value isrw_timeout, or5seconds ifrw_timeoutis not set.delivery_modemode โ Sets the delivery mode of each message sent to broker. The following values are accepted:persistentโ Delivery mode set topersistent(2). This is the default value. Messages may be written to the broker's disk depending on its setup.non-persistentโ Delivery mode set tonon-persistent(1). Messages will stay in broker's memory unless the broker is under memory pressure.
async
Asynchronous data filling wrapper for input stream. Fill data in a background thread, to decouple I/O operation from demux thread. It's the "bestie handles the icky I/O so you can keep vibing" protocol. โจ
async:<URL>
async:http://host/resource
async:cache:http://host/resource
bluray
Read BluRay playlist. Fancy disc energy. ๐ฟ
The accepted options are:
angleโ BluRay anglechapterโ Start chapter (1...N)playlistโ Playlist to read (BDMV/PLAYLIST/?????.mpls)
Examples:
Read longest playlist from BluRay mounted to /mnt/bluray:
bluray:/mnt/bluray
Read angle 2 of playlist 4 from BluRay mounted to /mnt/bluray, start from chapter 2:
-playlist 4 -angle 2 -chapter 2 bluray:/mnt/bluray
cache
Caching wrapper for input stream. Cache the input stream to temporary file. It brings seeking capability to live streams. Literally giving live streams a little memory, iconic. ๐ง โจ
The accepted options are:
read_ahead_limitโ Amount in bytes that may be read ahead when seeking isn't supported. Range is-1toINT_MAX.-1for unlimited. Default is65536.
URL Syntax is
cache:<URL>
concat
Physical concatenation protocol. Read and seek from many resources in sequence as if they were a unique resource. It's the "line up all the URLs and walk in formation" protocol. ๐
A URL accepted by this protocol has the syntax:
concat:<URL1>|<URL2>|...|<URLN>
where URL1, URL2, ..., URLN are the urls of the resource to be concatenated, each one possibly specifying a distinct protocol.
For example to read a sequence of files split1.mpeg, split2.mpeg, split3.mpeg with ffplay use the command:
ffplay concat:split1.mpeg\|split2.mpeg\|split3.mpeg
Note that you may need to escape the character | which is special for many shells. The shell said "not today" and you gotta backslash it. ๐
concatf
Physical concatenation protocol using a line break delimited list of resources. Read and seek from many resources in sequence as if they were a unique resource.
A URL accepted by this protocol has the syntax:
concatf:<URL>
where URL is the url containing a line break delimited list of resources to be concatenated, each one possibly specifying a distinct protocol. Special characters must be escaped with backslash or single quotes. See the "Quoting and escaping" section in the ffmpeg-utils(1) manual. ๐ฆ
For example to read a sequence of files split1.mpeg, split2.mpeg, split3.mpeg listed in separate lines within a file split.txt with ffplay use the command:
ffplay concatf:split.txt
Where split.txt contains the lines:
split1.mpeg
split2.mpeg
split3.mpeg
crypto
AES-encrypted stream reading protocol. Secret little stream, we see you. ๐
The accepted options are:
keyโ Set the AES decryption key binary block from given hexadecimal representation.ivโ Set the AES decryption initialization vector binary block from given hexadecimal representation.
Accepted URL formats:
crypto:<URL>
crypto+<URL>
data
Data in-line in the URI. See http://en.wikipedia.org/wiki/Data_URI_scheme. It's literally data just chilling inside the link. ๐
For example, to convert a GIF file given inline with ffmpeg:
ffmpeg -i "data:image/gif;base64,R0lGODdhCAAIAMIEAAAAAAAA//8AAP//AP///////////////ywAAAAACAAIAAADF0gEDLojDgdGiJdJqUX02iB4E8Q9jUMkADs=" smiley.png
fd
File descriptor access protocol. Lowkey powerful, highkey useful. ๐ซถ
The accepted syntax is:
fd: -fd <file_descriptor>
If fd is not specified, by default the stdout file descriptor will be used for writing, stdin for reading. Unlike the pipe protocol, fd protocol has seek support if it corresponding to a regular file. fd protocol doesn't support pass file descriptor via URL for security. ๐ก๏ธ
This protocol accepts the following options:
blocksizeโ sets the max block size for I/O ops, in bytes. Default isINT_MAX, which basically means "no limit, go off bestie". Setting it kinda low makes the user's cancel request get noticed faster โ which is a whole vibe when data transmission is slow ๐ญfdโ sets the file descriptor. That's it. That's the option. ๐
๐ฆ file ๐ฆ
The file access protocol, babes. You read from a file or write to a file. Iconic, lowkey the blueprint.
A file URL looks like this:
file:<filename>
where filename is the path of the file you're reading. Easy.
An URL with no protocol prefix is assumed to be a file URL, no questions asked. And depending on how it's built, an URL that looks like a Windows path with the drive letter chilling at the front also gets assumed to be a file URL โ tho that's usually not the case in builds for unix-like systems, iykyk.
So for example, to read from a file input.mpeg with ffmpeg you'd run:
ffmpeg -i file:input.mpeg output.mpeg
This protocol accepts these options, bestie:
truncateโ truncates existing files on write, if set to 1. A value of 0 means no truncating, hands off. Default value is 1.blocksizeโ sets the max block size for I/O ops, in bytes. Default isINT_MAX, which means the requested block size isn't limited at all. Setting it reasonably low improves user termination request reaction time, and that's genuinely valuable when your files are on a slow medium ๐followโ if set to 1, the protocol will retry reading at the end of the file, so you can read files that are still being written to. Not me reading a file mid-write โจ For this to actually terminate, you either need to use therw_timeoutoption, or use the interrupt callback (that one's for API users).seekableโ controls whether seekability is advertised on the file.0means non-seekable,-1means auto (seekable for normal files, non-seekable for named pipes).
So many demuxers handle seekable vs non-seekable resources differently, and overriding this might speed up opening certain files โ but at the cost of losing some features (e.g. accurate seeking). Trade-offs, bestie ๐
pkt_sizeโ sets the maximum packet size used for file I/O. A smaller value may reduce memory usage. A higher value may increase throughput, especially with networked filesystems.
For reading: if you explicitly set it, it overrides the default internal buffer size (32 KB) and limits the maximum amount of data read per operation.
For writing: this sets the size of each write operation. The default is 256 KB for regular files, 32 KB otherwise.
๐ ftp ๐
FTP (File Transfer Protocol). We're reading from or writing to remote resources using the FTP protocol, bestie ๐
The syntax is required to be this:
ftp://[user[:password]@]server[:port]/path/to/remote/resource.mpeg
This protocol accepts these options:
timeoutโ sets the timeout in microseconds of socket I/O operations used by the underlying low level operation. By default it's set to-1, which means the timeout is not specified. Vibes: unspecified.ftp-userโ sets a user to be used for authenticating to the FTP server. This is overridden by the user in the FTP URL. (URL stays winning ๐)ftp-passwordโ sets a password to be used for authenticating to the FTP server. This is overridden by the password in the FTP URL, or byftp-anonymous-passwordif no user is set.ftp-anonymous-passwordโ the password used when logging in as an anonymous user. Typically you should use an e-mail address here. fr fr.ftp-write-seekableโ controls seekability of the connection during encoding. If set to 1 the resource is supposed to be seekable, if set to 0 it's assumed not to be seekable. Default value is 0.
NOTE: the protocol can be used as output, but it's recommended that you don't, unless special care is taken (tests, customized server configuration etc.). Different FTP servers behave in different ways during seek operations, and ff* tools may produce incomplete content due to server limitations. So like... be careful, bestie ๐ญ
๐ง gopher ๐ง
Gopher protocol. That's the whole entry. Short and iconic, we love a minimal queen ๐
๐ธ gophers ๐ธ
Gophers protocol.
It's the Gopher protocol with TLS encapsulation. Glow-up secured ๐ฅ
๐ http ๐
HTTP (Hyper Text Transfer Protocol). The main character, honestly.
This protocol accepts these options:
seekableโ controls seekability of the connection. If set to 1 the resource is supposed to be seekable, if set to 0 it's assumed not to be seekable, and if set to -1 it'll try to autodetect whether it's seekable. Default value is -1.chunked_postโ if set to 1, use chunked Transfer-Encoding for posts. Default is 1.http_proxyโ sets the HTTP proxy to tunnel through, e.g.http://example.com:1234headersโ sets custom HTTP headers, and can override built in default headers. The value must be a string encoding the headers.content_typeโ sets a specific content type for the POST messages or for listen mode.user_agentโ overrides the User-Agent header. If not specified, the protocol will use a string describing the libavformat build (Lavf/<version>).refererโ sets the Referer header. Includes a 'Referer: URL' header in the HTTP request.multiple_requestsโ uses persistent connections if set to 1. Default is 0.request_sizeโ limits the size of requests made. This is useful for some pathological servers that throttle unbounded range requests, and also when you're expecting to seek frequently. Disabled (set to 0) by default.
Note that if you enable this option, it's strongly recommended that you also enable the multiple_requests option, as well as setting short_seek_size to the same value or higher. Doing so lets FFmpeg reuse a single HTTP connection wherever possible. Efficient queen ๐
initial_request_sizeโ limits the size of initial requests. Similar torequest_size, but only used during initial format parsing. Useful for formats like MXF or MOV that require frequent seeks during header parsing. It lasts until the demuxer makes a read request larger than this size (with no seek in between), after which the implementation will continue using requests as usual. Disabled (set to 0) by default.
Note that if you enable this option, it's strongly recommended that you also enable the multiple_requests option, as well as setting short_seek_size to the same value or higher.
post_dataโ sets custom HTTP post data.mime_typeโ exports the MIME type.http_versionโ exports the HTTP response version number. Usually"1.0"or"1.1".cookiesโ sets the cookies to be sent in future requests. The format of each cookie is the same as the value of a Set-Cookie HTTP response field. Multiple cookies can be delimited by a newline character.icyโ if set to 1, request ICY (SHOUTcast) metadata from the server. If the server supports this, the metadata has to be retrieved by the application by reading theicy_metadata_headersandicy_metadata_packetoptions. The default is 1.icy_metadata_headersโ if the server supports ICY metadata, this contains the ICY-specific HTTP reply headers, separated by newline characters.icy_metadata_packetโ if the server supports ICY metadata, andicywas set to 1, this contains the last non-empty metadata packet sent by the server. Applications interested in mid-stream metadata updates should poll it in regular intervals. Polling era, we love to see it โจmetadataโ sets an exported dictionary containing Icecast metadata from the bitstream, if present. Only useful with the C API.auth_typeโ sets the HTTP authentication type. There's no option for Digest, since this method requires getting nonce parameters from the server first and can't be used straight away like Basic. Rude of Digest tbh ๐noneโ choose the HTTP authentication type automatically. This is the default.basicโ choose the HTTP basic authentication.
Basic authentication sends a Base64-encoded string that contains a user name and password for the client. Base64 is not a form of encryption and should be considered the same as sending the user name and password in clear text (Base64 is a reversible encoding). If a resource needs to be protected, strongly consider using an authentication scheme other than basic authentication. HTTPS/TLS should be used with basic authentication. Without these additional security enhancements, basic authentication should not be used to protect sensitive or valuable information. Like genuinely bestie, do not do it ๐
send_expect_100โ sends anExpect: 100-continueheader for POST. If set to 1 it will send, if set to 0 it won't, and if set to -1 it'll try to send if it's applicable. Default value is -1.locationโ an exported dictionary containing the content location. Only useful with the C API.offsetโ sets the initial byte offset.end_offsetโ tries to limit the request to bytes preceding this offset.methodโ when used as a client option, it sets the HTTP method for the request.
When used as a server option, it sets the HTTP method that is going to be expected from the client(s). If the expected and the received HTTP method don't match, the client will be given a Bad Request response. When unset, the HTTP method is not checked for now. This will be replaced by autodetection in the future โ watching this space ๐
reconnectโ reconnects automatically when disconnected before EOF is hit.reconnect_at_eofโ if set, then eof is treated like an error and causes reconnection. This is useful for live / endless streams. Never-ending stream girlies rise ๐ซถreconnect_on_network_errorโ reconnects automatically in case of TCP/TLS errors during connect.reconnect_on_http_errorโ a comma separated list of HTTP status codes to reconnect on. The list can include specific status codes (e.g.'503') or the strings'4xx'/'5xx'.reconnect_streamedโ if set, then even streamed/non seekable streams will be reconnected on errors.reconnect_delay_maxโ sets the maximum delay in seconds after which to give up reconnecting.reconnect_max_retriesโ sets the maximum number of times to retry a connection. Default unset.reconnect_delay_total_maxโ sets the maximum total delay in seconds after which to give up reconnecting.respect_retry_afterโ if enabled, and aRetry-Afterheader is encountered, its requested reconnection delay will be honored, rather than using exponential backoff. Useful for429and503errors. Default enabled. Polite and correct ๐
listen
Okay so if you set this bad boy to 1, you get an experimental HTTP server ๐
. It's giving "I'm the server now" โ you can use it as an output option to send data, or as an input option to read data from a client via HTTP POST. Set it to 2 and you get an experimental multi-client HTTP server... except this is not yet implemented in ffmpeg.c and thus must not be used as a command line option ๐ญ. Like, the vibe is there but the code isn't, yk?
# Server side (sending):
ffmpeg -i somefile.ogg -c copy -listen 1 -f ogg http://<server>:<port>
# Client side (receiving):
ffmpeg -i http://<server>:<port> -c copy somefile.ogg
# Client can also be done with wget:
wget http://<server>:<port> -O somefile.ogg
# Server side (receiving):
ffmpeg -listen 1 -i http://<server>:<port> -c copy somefile.ogg
# Client side (sending):
ffmpeg -i somefile.ogg -chunked_post 0 -c copy -f ogg http://<server>:<port>
# Client can also be done with wget:
wget --post-file=somefile.ogg http://<server>:<port>
resourceโ the resource requested by a client, when the experimental HTTP server is in use โจreply_codeโ the HTTP code returned to the client, when the experimental HTTP server is in use ๐short_seek_sizeโ sets the threshold, in bytes, for when a readahead should be preferred over a seek and a new HTTP request. Genuinely useful, fr โ like, it makes sure the same connection gets used for reading large video packets with small audio packets in between ๐ซถ
๐ช HTTP Cookies
Some HTTP requests will straight-up get denied unless cookie values are passed in with the request ๐ค. The cookies option lets you specify those cookies. At the very least, each cookie must specify a value along with a path and domain. HTTP requests that match both the domain and path will automatically include the cookie value in the HTTP Cookie header field. Multiple cookies can be delimited by a newline, slay ๐
.
The required syntax to play a stream specifying a cookie is:
ffplay -cookies "nlqptid=nltid=tsn; path=/; domain=somedomain.com;" http://somedomain.com/somestream.m3u8
Icecast
Icecast protocol โ think "stream to Icecast servers" ๐๏ธโจ
This protocol accepts the following options:
ice_genreโ set the stream genre ๐ตice_nameโ set the stream name ๐ท๏ธice_descriptionโ set the stream description ๐ice_urlโ set the stream website URL ๐ice_publicโ set if the stream should be public. The default is0(not public) ๐user_agentโ override theUser-Agentheader. If not specified, a string of the form"Lavf/<version>"will be used ๐คpasswordโ set the Icecast mountpoint password ๐content_typeโ set the stream content type. This must be set if it is different fromaudio/mpegโ ๏ธlegacy_icecastโ this enables support for Icecast versions< 2.4.0, that do not support the HTTP PUT method but the SOURCE method ๐ตtlsโ establish a TLS (HTTPS) connection to Icecast ๐
icecast://[<username>[:<password>]@]<server>:<port>/<mountpoint>
ipfs
InterPlanetary File System (IPFS) protocol support ๐ชโจ. You can access files stored on the IPFS network through so-called gateways โ these are http(s) endpoints. This protocol wraps the IPFS native protocols (ipfs:// and ipns://) to be sent to such a gateway. Users can (and should) host their own node, which means this protocol will use your local gateway to access files on the IPFS network ๐ง
This protocol accepts the following options:
gatewayโ defines the gateway to use. When not set, the protocol will first try locating the local gateway by looking at$IPFS_GATEWAY,$IPFS_PATHand"$HOME/.ipfs/", in that order ๐
One can use this protocol in 2 ways. Using IPFS:
ffplay ipfs://<hash>
Or the IPNS protocol (IPNS is mutable IPFS):
ffplay ipns://<hash>
mmst
MMS (Microsoft Media Server) protocol over TCP ๐ฅ๏ธ
mmsh
MMS (Microsoft Media Server) protocol over HTTP ๐
The required syntax is:
mmsh://<server>[:<port>][/<app>][/<playpath>]
md5
MD5 output protocol ๐ข
Computes the MD5 hash of the data to be written, and on close writes this to the designated output โ or stdout if none is specified. It can be used to test muxers without writing an actual file, which is honestly iconic for testing ๐งชโจ
Some examples follow:
# Write the MD5 hash of the encoded AVI file to the file output.avi.md5.
ffmpeg -i input.flv -f avi -y md5:output.avi.md5
# Write the MD5 hash of the encoded AVI file to stdout.
ffmpeg -i input.flv -f avi -y md5:
Heads up bestie ๐ โ some formats (typically MOV) require the output protocol to be seekable, so they will fail with the MD5 output protocol. No cap, that's just how it is.
pipe
UNIX pipe access protocol ๐ฐ
Read and write from UNIX pipes. The accepted syntax is:
pipe:[<number>]
If fd isn't specified, number is the number corresponding to the file descriptor of the pipe (e.g. 0 for stdin, 1 for stdout, 2 for stderr). If number is not specified, by default the stdout file descriptor will be used for writing, stdin for reading โจ
For example, to read from stdin with ffmpeg:
cat test.wav | ffmpeg -i pipe:0
# ...this is the same as...
cat test.wav | ffmpeg -i pipe:
For writing to stdout with ffmpeg:
ffmpeg -i test.wav -f avi pipe:1 | cat > test.avi
# ...this is the same as...
ffmpeg -i test.wav -f avi pipe: | cat > test.avi
This protocol accepts the following options:
blocksizeโ set I/O operation maximum block size, in bytes. Default value is"INT_MAX", which results in not limiting the requested block size. Setting this value reasonably low improves user termination request reaction time โ lowkey valuable if data transmission is slow ๐fdโ set file descriptor ๐ฏ
Same warning as above, bestie ๐ญ โ some formats (typically MOV) require the output protocol to be seekable, so they will fail with the pipe output protocol.
prompeg
Pro-MPEG Code of Practice #3 Release 2 FEC protocol ๐กโจ
The Pro-MPEG CoP#3 FEC is a 2D parity-check forward error correction mechanism for MPEG-2 Transport Streams sent over RTP. Very "protect the packets" of it ๐
This protocol must be used in conjunction with the "rtp_mpegts" muxer and the "rtp" protocol ๐ซถ
The required syntax is:
-f rtp_mpegts -fec prompeg=<option>=<val>... rtp://<hostname>:<port>
The destination UDP ports are "port + 2" for the column FEC stream and "port + 4" for the row FEC stream ๐
This protocol accepts the following options:
l=nโ the number of columns (4-20,LxD <= 100) ๐d=nโ the number of rows (4-20,LxD <= 100) ๐
Example usage:
-f rtp_mpegts -fec prompeg=l=8:d=4 rtp://<hostname>:<port>
rist
Reliable Internet Streaming Transport protocol ๐
The accepted options are:
rist_profileโ supported values:simplemainโ this one is default ๐advanced
buffer_sizeโ set internal RIST buffer size in milliseconds for retransmission of data. Default value is0, which means the librist default (1 sec). Maximum value is 30 seconds โฑ๏ธfifo_sizeโ size of the librist receiver output fifo in number of packets. This must be a power of 2. Defaults to8192(vs the librist default of1024) ๐ฆoverrun_nonfatal=1|0โ survive in case of librist fifo buffer overrun. Default value is0๐pkt_sizeโ set maximum packet size for sending data.1316by default ๐จlog_levelโ set loglevel for RIST logging messages. You only need to set this if you explicitly want to enable debug level messages or packet loss simulation; otherwise the regular loglevel is respected ๐secretโ set override of encryption secret, by default is unset ๐encryptionโ set encryption type, by default is disabled. Acceptable values are128and256๐
rtmp
Real-Time Messaging Protocol ๐บโจ
The Real-Time Messaging Protocol (RTMP) is used for streaming multimedia content across a TCP/IP network ๐
The required syntax is:
rtmp://[<username>:<password>@]<server>[:<port>][/<app>][/<instance>][/<playpath>]
The accepted parameters are:
usernameโ an optional username (mostly for publishing) ๐คpasswordโ an optional password (mostly for publishing) ๐serverโ the address of the RTMP server ๐ฅ๏ธportโ the number of the TCP port to use (by default is1935) ๐ขappโ it is the name of the application to access. It usually corresponds to the path where the application is installed on the RTMP server (e.g./ondemand/,/flash/live/, etc.). You can override the value parsed from the URI through the"rtmp_app"option, too ๐ฏplaypathโ it is the path or name of the resource to play with reference to the application specified in app, may be prefixed by"mp4:". You can override the value parsed from the URI through the"rtmp_playpath"option, too ๐ฌlistenโ act as a server, listening for an incoming connection ๐timeoutโ maximum time to wait for the incoming connection. Implies listen โณ
Additionally, the following parameters can be set via command line options (or in code via "AVOption"s):
rtmp_appโ name of application to connect on the RTMP server. This option overrides the parameter specified in the URI ๐ท๏ธrtmp_bufferโ set the client buffer time in milliseconds. The default is3000๐งrtmp_connโ extra arbitrary AMF connection parameters, parsed from a string, e.g. like"B:1 S:authMe O:1 NN:code:1.23 NS:flag:ok O:0". Each value is prefixed by a single character denoting the type:Bfor Boolean,Nfor number,Sfor string,Ofor object, orZfor null, followed by a colon. For Booleans the data must be either0or1for FALSE or TRUE, respectively. Likewise for Objects the data must be0or1to end or begin an object, respectively. Data items in subobjects may be named, by prefixing the type with'N'and specifying the name before the value (i.e."NB:myFlag:1"). This option may be used multiple times to construct arbitrary AMF sequences ๐งฉrtmp_enhanced_codecsโ specify the list of codecs the client advertises to support in an enhanced RTMP stream. This option should be set to a comma separated list of fourcc values, like"hvc1,av01,vp09"for multiple codecs or"hvc1"for only one codec. The specified list will be presented in the"fourCcLive"property of the Connect Command Message ๐ฃrtmp_flashverโ version of the Flash plugin used to run the SWF player. The default isLNX 9,0,124,2. (When publishing, the default isFMLE/3.0 (compatible; <libavformat version>).) ๐ฐ๏ธrtmp_flush_intervalโ how many packets get flushed in the same request (RTMPT only, bestie). The default is10.rtmp_liveโ tells it the media is a live stream. Heads up: no resuming or seeking in live streams is possible, so don't even try. The default value is"any", which lowkey means the subscriber first tries to play the live stream named in the playpath, and if a live stream with that name isn't found, it plays the recorded stream instead. The other possible values are"live"and"recorded". Slay.rtmp_pageurlโ the URL of the web page where the media was embedded. By default no value will be sent. ๐rtmp_playpathโ the stream identifier to play or to publish. This option overrides the parameter specified in the URI, so it wins, periodt.rtmp_subscribeโ the name of the live stream to subscribe to. By default no value will be sent; it is only sent if the option is specified or ifrtmp_liveis set tolive. iykyk.rtmp_swfhashโ SHA256 hash of the decompressed SWF file (32bytes). Don't ask, just pass it. ๐rtmp_swfsizeโ the size of the decompressed SWF file, which is required for SWFVerification. No swfsize, no verification, bestie.rtmp_swfurlโ the URL of the SWF player for the media. By default no value will be sent.rtmp_swfverifyโ URL to the player swf file, and it computes hash/size automatically for you. auto-magic โจrtmp_tcurlโ the URL of the target stream. Defaults toproto://host[:port]/app.tcp_nodelay=1|0โ setsTCP_NODELAYto disable Nagle's algorithm. Default value is0.
Remark: writing to the socket is currently not optimized to minimize system calls and reduces the efficiency / effect of TCP_NODELAY. So likeโฆ it's giving "we tried" ๐ญ but that's literally what the docs say.
tcp_keepalive=1|0โ turn on the TCP keepalive mechanism to detect dead peers and help maintain long-lived idle connections. Default value is0.
Only the basic keepalive option (SO_KEEPALIVE) can be enabled or disabled. Platform-specific tuning parameters such as TCP_KEEPIDLE, TCP_KEEPINTVL, or TCP_KEEPCNT are not configurable and will use the operating system's default values. Soz. ๐ซถ
For example, to read with ffplay a multimedia resource named "sample" from the application "vod" from an RTMP server "myserver":
ffplay rtmp://myserver/vod/sample
To publish to a password protected server, passing the playpath and app names separately:
ffmpeg -re -i <input> -f flv -rtmp_playpath some/long/path -rtmp_app long/app/name rtmp://username:password@myserver/
rtmpe
Encrypted Real-Time Messaging Protocol. ๐
The Encrypted Real-Time Messaging Protocol (RTMPE) is used for streaming multimedia content within standard cryptographic primitives, consisting of Diffie-Hellman key exchange and HMACSHA256, generating a pair of RC4 keys. It's giving cryptography class but make it streaming. ๐ฅ
rtmps
Real-Time Messaging Protocol over a secure SSL connection. ๐ฆ
The Real-Time Messaging Protocol (RTMPS) is used for streaming multimedia content across an encrypted connection.
rtmpt
Real-Time Messaging Protocol tunneled through HTTP. ๐
The Real-Time Messaging Protocol tunneled through HTTP (RTMPT) is used for streaming multimedia content within HTTP requests to traverse firewalls. Firewall said no, RTMPT said bet.
rtmpte
Encrypted Real-Time Messaging Protocol tunneled through HTTP.
The Encrypted Real-Time Messaging Protocol tunneled through HTTP (RTMPTE) is used for streaming multimedia content within HTTP requests to traverse firewalls. Encrypted and sneaky, we love a multitasking icon. ๐
rtmpts
Real-Time Messaging Protocol tunneled through HTTPS. ๐
The Real-Time Messaging Protocol tunneled through HTTPS (RTMPTS) is used for streaming multimedia content within HTTPS requests to traverse firewalls.
libsmbclient
libsmbclient permits one to manipulate CIFS/SMB network resources. Networking but make it Windows-flavored.
Following syntax is required.
smb://[[domain:]user[:password@]]server[/share[/path[/file]]]
This protocol accepts the following options.
timeoutโ set the timeout in milliseconds of socket I/O operations used by the underlying low level operation. By default it is set to-1, which means that the timeout is not specified.truncateโ truncate existing files on write, if set to1. A value of0prevents truncating. Default value is1.workgroupโ set the workgroup used for making connections. By default workgroup is not specified.
For more information see: http://www.samba.org/. ๐
libssh
Secure File Transfer Protocol via libssh. Read from or write to remote resources using SFTP protocol. Bestie, it's file transfer but secure.
Following syntax is required.
sftp://[user[:password]@]server[:port]/path/to/remote/resource.mpeg
This protocol accepts the following options.
timeoutโ set the timeout of socket I/O operations used by the underlying low level operation. By default it is set to-1, which means that the timeout is not specified.truncateโ truncate existing files on write, if set to1. A value of0prevents truncating. Default value is1.private_keyโ specify the path of the file containing the private key to use during authorization. By defaultlibsshsearches for keys in the~/.ssh/directory.
Example: play a file stored on a remote server.
ffplay sftp://user:password@server_address:22/home/user/resource.mpeg
librtmp rtmp, rtmpe, rtmps, rtmpt, rtmpte
Real-Time Messaging Protocol and its variants supported through librtmp. Yes, all of them, the whole squad. ๐ฏโโ๏ธ
Requires the presence of the librtmp headers and library during configuration. You need to explicitly configure the build with "--enable-librtmp". If enabled, this will replace the native RTMP protocol โ like, fully swap it out, no cap.
This protocol provides most client functions and a few server functions needed to support RTMP, RTMP tunneled in HTTP (RTMPT), encrypted RTMP (RTMPE), RTMP over SSL/TLS (RTMPS) and tunneled variants of these encrypted types (RTMPTE, RTMPTS). It does the most, honestly.
The required syntax is:
<rtmp_proto>://<server>[:<port>][/<app>][/<playpath>] <options>
where rtmp_proto is one of the strings "rtmp", "rtmpt", "rtmpe", "rtmps", "rtmpte", "rtmpts" corresponding to each RTMP variant, and server, port, app and playpath have the same meaning as specified for the RTMP native protocol. options contains a list of space-separated options of the form key=val.
See the librtmp manual page (man 3 librtmp) for more information. Go read it, it's giving bonus lore. ๐
For example, to stream a file in real-time to an RTMP server using ffmpeg:
ffmpeg -re -i myfile -f flv rtmp://myserver/live/mystream
To play the same stream using ffplay:
ffplay "rtmp://myserver/live/mystream live=1"
rtp
Real-time Transport Protocol. โจ
The required syntax for an RTP URL is:
rtp://<hostname>[:<port>][?<options>]
port specifies the RTP port to use.
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values. Cute and URL-safe, we stan. ๐ง
Options can also can be specified via command line options (or in code via "AVOption"s).
The list of supported options follows.
ttl=nโ set the TTL (Time-To-Live) value (for multicast only).rtcpport=nโ set the remote RTCP port to n.localport,local_rtpport,localrtpport=nโ set the local RTP port to n.
Using the localport option name is deprecated and should not be used. Like, it still works but don't, bestie. ๐
local_rtcpport,localrtcpport=n โ set the local RTCP port to n.pkt_size=nโ set max packet size (in bytes) to n.buffer_size=sizeโ set the maximum UDP socket buffer size in bytes.connect=0|1โ do aconnect()on the UDP socket (if set to1) or not (if set to0).sources=ip[,ip]โ list allowed source IP addresses.block=ip[,ip]โ list disallowed (blocked) source IP addresses. Blocked blocked blocked. ๐write_to_source=0|1โ send packets to the source address of the latest received packet (if set to1) or to a default remote address (if set to0).localaddr=addrโ local IP address of a network interface used for sending packets or joining multicast groups.timeout=nโ set the timeout (in microseconds) of socket I/O operations to n.
Important notes, and yes these are important, don't skip them:
- If
rtcpportis not set, the RTCP port will be set to the RTP port value plus1. - If
localrtpport(the local RTP port) is not set, any available port will be used for the local RTP and RTCP ports. - If
localrtcpport(the local RTCP port) is not set, it will be set to the local RTP port value plus1.
rtsp
Real-Time Streaming Protocol. ๐ฌ
RTSP is not technically a protocol handler in libavformat โ plot twist โ it is a demuxer and muxer. The demuxer supports both normal RTSP (with data transferred over RTP; this is used by e.g. Apple and Microsoft) and Real-RTSP (with data transferred over RDT).
The muxer can be used to send a stream using RTSP ANNOUNCE to a server supporting it (currently Darwin Streaming Server and Mischa Spiegelmock's https://github.com/revmischa/rtsp-server).
The required syntax for a RTSP url is:
rtsp://<hostname>[:<port>]/<path>
Options can be set on the ffmpeg/ffplay command line, or set in code via "AVOption"s or in avformat_open_input.
Muxer
The following options are supported.
rtsp_transportโ set RTSP transport protocols.
It accepts the following values:
udpโ use UDP as lower transport protocol.tcpโ use TCP (interleaving within the RTSP control channel) as lower transport protocol.
Default value is 0.
rtsp_flagsโ set RTSP flags.
The following values are accepted:
latmโ use MP4A-LATM packetization instead of MPEG4-GENERIC for AAC.rfc2190โ use RFC 2190 packetization instead of RFC 4629 for H.263.skip_rtcpโ don't send RTCP sender reports.h264_mode0โ use mode 0 for H.264 in RTP.send_byeโ send RTCP BYE packets when finishing. Bye bestie ๐
Default value is 0.
min_portโ set minimum local UDP port. Default value is5000.max_portโ set maximum local UDP port. Default value is65000.buffer_sizeโ set the maximum socket buffer size in bytes.pkt_sizeโ set max send packet size (in bytes). Default value is1472.
Demuxer
The following options are supported.
initial_pauseโ do not start playing the stream immediately if set to1. Default value is0. Sometimes you just need a second to breathe, y'know? ๐ธrtsp_transportโ set RTSP transport protocols.
It accepts the following values:
udpโ use UDP as lower transport protocol.tcpโ use TCP (interleaving within the RTSP control channel) as lower transport protocol.udp_multicastโ use UDP multicast as lower transport protocol.httpโ use HTTP tunneling as lower transport protocol, which is useful for passing proxies.
httpsโ use HTTPS tunneling as the lower transport protocol โ super handy for sneaking through proxies and honestly just the move for security reasons. ๐
You can stack up multiple lower transport protocols in one go โ they get tried one at a time (if setting one up fails, it just moves onto the next, no drama, no cap). Tiny catch tho: for the muxer, only the tcp and udp options work. ๐ซถ
rtsp_flagsโ sets the RTSP flags. Here's the accepted value list, bestie:filter_srcโ accept packets only from the negotiated peer address and port. Picky on purpose. ๐listenโ act as a server and listen for an incoming connection. main character energy only. ๐prefer_tcpโ try TCP for RTP transport first, if TCP is actually available as RTSP RTP transport.satip_rawโ export the raw MPEG-TS stream instead of demuxing it. This flag literally just writes out the raw stream with the original PAT/PMT/PIDs intact. โจ
Default value is none. (yes, boring default, I know ๐)
allowed_media_typesโ set which media types you'll accept from the server. The accepted flags:videoaudiodatasubtitle
By default it accepts all media types. generous queen ๐ธ
min_portโ minimum local UDP port. Default value is5000.max_portโ maximum local UDP port. Default value is65000.listen_timeoutโ maximum timeout (in seconds) to establish an initial connection. Heads up: settinglisten_timeout> 0 also setsrtsp_flagstolisten. Default is-1, which means an infinite timeout when listen mode is set. ๐ฐ๏ธreorder_queue_sizeโ number of packets to buffer for handling reordered packets.timeoutโ set the socket TCP I/O timeout, in microseconds.user_agentโ override the User-Agent header. If you don't specify it, it defaults to the libavformat identifier string. iykyk ๐buffer_sizeโ set the maximum socket buffer size in bytes.
When receiving data over UDP, the demuxer tries to reorder received packets (because yeah, they can arrive out of order, or packets can get lost totally โ rude ๐ญ). This can be disabled by setting the maximum demuxing delay to zero (via the max_delay field of AVFormatContext).
When watching multi-bitrate Real-RTSP streams with ffplay, you can choose which streams to display with -vst n and -ast n for video and audio respectively โ and you can switch them on the fly by pressing v and a. iconic little party trick ๐ฆ
๐ฌ Examples
The following examples all make use of the ffplay and ffmpeg tools.
- Watch a stream over UDP, with a max reordering delay of 0.5 seconds:
ffplay -max_delay 500000 -rtsp_transport udp rtsp://server/video.mp4
- Watch a stream tunneled over HTTP:
ffplay -rtsp_transport http rtsp://server/video.mp4
- Send a stream in realtime to a RTSP server, for others to watch:
ffmpeg -re -i <input> -f rtsp -muxdelay 0.1 rtsp://server/live.sdp
- Receive a stream in realtime:
ffmpeg -rtsp_flags listen -i rtsp://ownaddress/live.sdp <output>
sap
Session Announcement Protocol (RFC 2974). Ngl, this isn't technically a protocol handler in libavformat โ it's a muxer and a demuxer. It's used for signalling RTP streams by announcing the SDP for those streams on a separate port, regularly, like clockwork. โญ
Muxer
The syntax for a SAP url given to the muxer is:
sap://<destination>[:<port>][?<options>]
The RTP packets are sent to destination on port port, or to port 5004 if no port is specified. options is a &-separated list. The following options are supported:
announce_addr=address โ specify the destination IP address for sending the announcements to. If omitted, announcements go to the commonly used SAP announcement multicast address224.2.127.254(sap.mcast.net), orff0e::2:7ffeif destination is an IPv6 address. ๐ฎannounce_port=port โ specify the port to send the announcements on, defaults to9875if not specified.ttl=ttl โ specify the time to live value for the announcements and RTP packets, defaults to255.same_port=0|1โ if set to1, send all RTP streams on the same port pair. If zero (the default), all streams are sent on unique ports, with each stream on a port 2 numbers higher than the previous. VLC/Live555 requires this to be set to1to be able to receive the stream. Meanwhile the RTP stack in libavformat for receiving requires all streams to be sent on unique ports. picky picky ๐
Example command lines follow.
To broadcast a stream on the local subnet, for watching in VLC:
ffmpeg -re -i <input> -f sap sap://224.0.0.255?same_port=1
Similarly, for watching in ffplay:
ffmpeg -re -i <input> -f sap sap://224.0.0.255
And for watching in ffplay, over IPv6:
ffmpeg -re -i <input> -f sap sap://[ff0e::1:2:3:4]
Demuxer
The syntax for a SAP url given to the demuxer is:
sap://[<address>][:<port>]
address is the multicast address to listen for announcements on โ if omitted, the default 224.2.127.254 (sap.mcast.net) is used. port is the port that is listened on, 9875 if omitted.
The demuxers listens for announcements on the given address and port. Once an announcement is received, it tries to receive that particular stream. ๐ง
Example command lines follow.
To play back the first stream announced on the normal SAP multicast address:
ffplay sap://
To play back the first stream announced on one the default IPv6 SAP multicast address:
ffplay sap://[ff0e::2:7ffe]
sctp
Stream Control Transmission Protocol.
The accepted URL syntax is:
sctp://<host>:<port>[?<options>]
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values. ๐ง
Options can also can be specified via command line options (or in code via AVOptions).
The list of supported options follows.
listenโ if set to any value, listen for an incoming connection. Outgoing connection is done by default.max_streamsโ set the maximum number of streams. By default no limit is set.
srt
Haivision Secure Reliable Transport Protocol via libsrt.
The supported syntax for a SRT URL is:
srt://<hostname>:<port>[?<options>]
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values.
Options can also can be specified via command line options (or in code via AVOptions).
The list of supported options follows. buckle up bestie, it's a long one ๐
connect_timeout=milliseconds โ connection timeout. SRT cannot connect for RTT > 1500 msec (2 handshake exchanges) with the default connect timeout of 3 seconds. This option applies to the caller and rendezvous connection modes. The connect timeout is 10 times the value set for the rendezvous mode (which can be used as a workaround for this connection problem with earlier versions).ffs=bytes โ Flight Flag Size (Window Size), in bytes. FFS is actually an internal parameter and you should set it to not less thanrecv_buffer_sizeandmss. The default value is relatively large, therefore unless you set a very large receiver buffer, you do not need to change this option. Default value is25600.inputbw=bytes/seconds โ sender nominal input rate, in bytes per seconds. Used along withoheadbw, whenmaxbwis set to relative (0), to calculate maximum sending rate when recovery packets are sent along with the main media stream:inputbw * (100 + oheadbw) / 100โ ifinputbwis not set whilemaxbwis set to relative (0), the actual input rate is evaluated inside the library. Default value is0.iptos=tos โ IP Type of Service. Applies to sender only. Default value is0xB8.ipttl=ttl โ IP Time To Live. Applies to sender only. Default value is64.latency=microseconds โ Timestamp-based Packet Delivery Delay. Used to absorb bursts of missed packet retransmissions. This flag sets bothrcvlatencyandpeerlatencyto the same value. Note that prior to version1.3.0this is the only flag to set the latency, however this is effectively equivalent to settingpeerlatencywhen side is sender andrcvlatencywhen side is receiver, and the bidirectional stream sending is not supported.listen_timeout=microseconds โ set socket listen timeout.maxbw=bytes/seconds โ maximum sending bandwidth, in bytes per seconds.-1โ infinite (CSRTCC limit is 30mbps)0โ relative to input rate (seeinputbw)- >0 โ absolute limit value
Default value is 0 (relative).
mode=caller|listener|rendezvousโ connection mode.calleropens client connection.listenerstarts server to listen for incoming connections.rendezvoususe Rendez-Vous connection mode.
Default value is caller.
mss=bytes โ Maximum Segment Size, in bytes. Used for buffer allocation and rate calculation using a packet counter assuming fully filled packets. The smallest MSS between the peers is used. This is1500by default in the overall internet. This is the maximum size of the UDP packet and can be only decreased, unless you have some unusual dedicated network settings. Default value is1500.nakreport=1|0โ if set to1, Receiver will sendUMSG_LOSSREPORTmessages periodically until a lost packet is retransmitted or intentionally dropped. Default value is1.oheadbw=percents โ recovery bandwidth overhead above input rate, in percents. Seeinputbw. Default value is25%.passphrase=string โ HaiCrypt Encryption/Decryption Passphrase string, length from 10 to 79 characters. The passphrase is the shared secret between the sender and the receiver. It is used to generate the Key Encrypting Key using PBKDF2 (Password-Based Key Derivation Function). It is used only ifpbkeylenis non-zero. It is used on the receiver only if the received data is encrypted. The configured passphrase cannot be recovered (write-only). ๐
so real โ write-only means write-only, don't come crying when you can't read it back ๐ญ
enforced_encryption=1|0โ if true, both connection parties must have the same password set (including empty, that is, with no encryption). If the password doesn't match or only one side is unencrypted, the connection is rejected. Default is true.kmrefreshrate=packets โ the number of packets to be transmitted after which the encryption key is switched to a new key. Default is-1.-1means auto (0x1000000in srt library). The range for this option is integers in the 0 -INT_MAX.kmpreannounce=packetsโ the gap between when a brand-new encryption key gets sent and when the actual switchover goes down. This value also applies to the next interval, like, the one between switchover happening and the old encryption key getting decommissioned. Default is-1, and-1means auto (that's0x1000in the srt library). Range is integers in the0โ"INT_MAX"zone โจsnddropdelay=microsecondsโ the sender's little extra delay before it drops packets. This delay gets added onto the default drop delay time interval value.
Special value -1: don't drop packets on the sender at all, periodt ๐
payload_size=bytesโ sets the maximum declared size of a packet moved during a single call to the sending function in Live mode. Use0if this value isn't used (which is the default in file mode). Default is-1(automatic), which typically means MPEG-TS; if you're gonna use SRT to send any different kind of payload โ like, say, wrapping a live stream in very small frames โ then you can use a bigger maximum frame size, though not greater than1456bytes ๐pkt_size=bytesโ alias forpayload_size. Same vibe, different name ๐ซถpeerlatency=microsecondsโ the latency value (as described over inrcvlatency) that the sender side sets as a minimum value for the receiver.pbkeylen=bytesโ sender encryption key length, in bytes. You can only set it to0,16,24and32. Sender encryption gets enabled if it's not0. Not required on the receiver (set it to0), because the key size is obtained from the sender in the HaiCrypt handshake. Default value is0.rcvlatency=microsecondsโ the time that should elapse between the moment a packet was sent and the moment it's delivered to the receiver application in the receiving function. This time should be a buffer time big enough to cover the time spent sending, an unexpectedly extended RTT time, and the time needed to retransmit the lost UDP packet. The effective latency value ends up being the max of this option's value and thepeerlatencyvalue set by the peer side. Before version1.3.0this option was only available aslatencyโ history, bestie ๐recv_buffer_size=bytesโ set the UDP receive buffer size, expressed in bytes.send_buffer_size=bytesโ set the UDP send buffer size, expressed in bytes.timeout=microsecondsโ set the raise-error timeouts for read, write and connect operations. Heads up tho: the SRT library has its own internal timeouts that can be controlled separately, and the value you set here is only a cap on those ๐tlpktdrop=1|0โ Too-late Packet Drop. When it's enabled on the receiver, it skips missing packets that haven't been delivered in time and delivers the following packets to the application once their time-to-play has come. It also sends a fake ACK to the sender. When it's enabled on the sender and enabled on the receiving peer, the sender drops the older packets that have no chance of being delivered in time. It gets automatically enabled in the sender if the receiver supports it โจsndbuf=bytesโ set the send buffer size, expressed in bytes.rcvbuf=bytesโ set the receive buffer size, expressed in bytes.
Careful bestie: the receive buffer must not be greater than ffs.
lossmaxttl=packetsโ the value up to which the Reorder Tolerance may grow. When Reorder Tolerance is> 0, the packet loss report gets delayed until that number of packets come in. Reorder Tolerance increases every time a "belated" packet has come in but it wasn't due to retransmission (basically when UDP packets tend to come out of order), by the difference between the latest sequence and this packet's sequence โ and not more than the value of this option. By default it's0, which means the mechanism is turned off and the loss report is always sent immediately upon experiencing a "gap" in sequences ๐minversionโ the minimum SRT version that's required from the peer. A connection to a peer that doesn't satisfy the minimum version requirement will be rejected, no exceptions.
The version format in hex is 0xXXYYZZ for x.y.z in human readable form.
streamid=stringโ a string limited to 512 characters that can be set on the socket before connecting. This stream ID will be able to be retrieved by the listener side from the socket that's returned fromsrt_acceptand was connected by a socket with that set stream ID. SRT does not enforce any special interpretation of the contents of this string, it's just vibes. This option doesn't make sense in Rendezvous connection; the result might be that simply one side will override the value from the other side and it's a matter of luck which one would win ๐srt_streamid=stringโ alias forstreamid, here purely to avoid conflict with the ffmpeg command line option ๐smoother=live|fileโ the type of Smoother used for the transmission for that socket, which is the thing responsible for the transmission and congestion control. The Smoother type must be exactly the same on both connecting parties, otherwise the connection gets rejected. No matching fits, no connection ๐messageapi=1|0โ when set, this socket uses the Message API; otherwise it uses the Buffer API. Note that in live mode (seetranstype) there's only the message API available. In File mode you can choose between two modes:
Stream API (the default, when this option is false). In this mode you may send as many data as you wish with one sending instruction, or even use dedicated functions that read directly from a file. The internal facility takes care of any speed and congestion control. When receiving, you can also receive as many data as desired โ the data that isn't extracted will be waiting for the next call. There's no boundary between data portions in Stream mode.
Message API. In this mode your single sending instruction passes exactly one piece of data that has boundaries (a message). Contrary to Live mode, this message may span across multiple UDP packets and the only size limitation is that it shall fit as a whole in the sending buffer. The receiver shall use as large a buffer as necessary to receive the message, otherwise the message will not be given up. When the message is not complete (not all packets received or there was a packet loss) it will not be given up.
transtype=live|fileโ sets the transmission type for the socket. In particular, setting this option sets multiple other parameters to their default values as required for a particular transmission type.
live: set options as for live transmission. In this mode you should send, by one sending instruction, only so many data that fit in one UDP packet, limited to the value defined first in payload_size (1316 is the default in this mode). There's no speed control in this mode, only the bandwidth control โ if configured โ so you don't exceed the bandwidth with the overhead transmission (retransmitted and control packets).
file: set options as for non-live transmission. See messageapi for further explanations โจ
linger=secondsโ the number of seconds the socket waits for unsent data when closing. Default is-1.-1means auto (off with0seconds in live mode, on with180seconds in file mode). Range is integers in the0โ"INT_MAX"zone.tsbpd=1|0โ when true, use Timestamp-based Packet Delivery mode. The default behavior depends on the transmission type: enabled in live mode, disabled in file mode.
For more information see: <https://github.com/Haivision/srt> ๐ฆ
๐ srtp
Secure Real-time Transport Protocol. Yes, the secure one, she's serving encryption ๐
The accepted options are:
srtp_in_suitesrtp_out_suite
Select input and output encoding suites.
Supported values:
AES_CM_128_HMAC_SHA1_80
SRTP_AES128_CM_HMAC_SHA1_80
AES_CM_128_HMAC_SHA1_32
SRTP_AES128_CM_HMAC_SHA1_32
srtp_in_paramssrtp_out_params
Set input and output encoding parameters, which are expressed by a base64-encoded representation of a binary block. The first 16 bytes of this binary block are used as the master key, and the following 14 bytes are used as the master salt. Cute little split, honestly ๐
๐ผ subfile
Virtually extract a segment of a file or another stream. The underlying stream must be seekable, bestie โ no exceptions, it needs to be able to jump around โจ
Accepted options:
startโ start offset of the extracted segment, in bytes.endโ end offset of the extracted segment, in bytes. If set to0, extract till the end of the file.
Examples:
Extract a chapter from a DVD VOB file (start and end sectors obtained externally and multiplied by 2048):
subfile,,start,153391104,end,268142592,,:/media/dvd/VIDEO_TS/VTS_08_1.VOB
Play an AVI file directly from a TAR archive:
subfile,,start,183241728,end,366490624,,:archive.tar
Play a MPEG-TS file from start offset till end:
subfile,,start,32815239,end,0,,:video.ts
๐ tee
Writes the output to multiple protocols. The individual outputs are separated by | โ one little pipeline bar and you're cloning your output, main character energy fr fr ๐
tee:file://path/to/local/this.avi|file://path/to/local/that.avi
๐ tcp
Transmission Control Protocol. The reliable one, the one that checks in on you ๐
The required syntax for a TCP url is:
tcp://<hostname>:<port>[?<options>]
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values.
Options can also be specified via command line options (or in code via AVOptions).
The list of supported options follows.
listen=2|1|0โ listen for an incoming connection.0disables listen,1enables listen in single client mode,2enables listen in multi-client mode. Default value is0.local_addr=addrโ local IP address of a network interface used for the tcp socket connect.local_port=portโ local port used for the tcp socket connect.timeout=microsecondsโ set the raise error timeout, expressed in microseconds.
This option is only relevant in read mode: if no data arrived in more than this time interval, raise error ๐ค
listen_timeout=millisecondsโ set the listen timeout, expressed in milliseconds.recv_buffer_size=bytesโ set the receive buffer size, expressed in bytes.send_buffer_size=bytesโ set the send buffer size, expressed in bytes.tcp_nodelay=1|0โ setTCP_NODELAYto disable Nagle's algorithm. Default value is0.
Remark: writing to the socket is currently not optimized to minimize system calls, and that reduces the efficiency / effect of TCP_NODELAY. Just so you know, bestie ๐
tcp_mss=bytesโ set the maximum segment size for outgoing TCP packets, expressed in bytes.
Like, the classic listen-y example โ setting up a listening TCP connection with ffmpeg, and then bopping over to it with ffplay:
ffmpeg -i <input> -f <format> tcp://<hostname>:<port>?listen
ffplay tcp://<hostname>:<port>
tls
Transport Layer Security (TLS) / Secure Sockets Layer (SSL) ๐ the locked-up, encrypted bestie of the protocols.
The required syntax for a TLS/SSL url is:
tls://<hostname>:<port>[?<options>]
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values.
Options can also can be specified via command line options (or in code via "AVOption"s).
The list of supported options follows.
ca_file,cafile=filename โ a file containing certificate authority (CA) root certificates to treat as trusted. If the linked TLS library contains a default this might not need to be specified for verification to work, but not all libraries and setups have defaults built in. The file must be in OpenSSL PEM format.tls_verify,verify=1|0โ if enabled, try to verify the peer that we are communicating with. Note, if using OpenSSL, this currently only makes sure that the peer certificate is signed by one of the root certificates in the CA database, but it does not validate that the certificate actually matches the host name we are trying to connect to. (With other backends, the host name is validated as well.) This is disabled by default since it requires a CA database to be provided by the caller in many cases.cert_file,cert=filename โ a file containing a certificate to use in the handshake with the peer. (When operating as server, in listen mode, this is more often required by the peer, while client certificates only are mandated in certain setups.) ๐key_file,key=filename โ a file containing the private key for the certificate.listen=1|0โ if enabled, listen for connections on the provided port, and assume the server role in the handshake instead of the client role.http_proxyโ the HTTP proxy to tunnel through, e.g."http://example.com:1234". The proxy must support theCONNECTmethod.
Example command lines:
To create a TLS/SSL server that serves an input stream.
ffmpeg -i <input> -f <format> tls://<hostname>:<port>?listen&cert=<server.crt>&key=<server.key>
To play back a stream from the TLS/SSL server using ffplay:
ffplay tls://<hostname>:<port>
dtls
Datagram Transport Layer Security (DTLS) โ same vibe as TLS, except it's riding on UDP because it literally cannot sit still. ๐ฆ
The required syntax for a DTLS URL is:
dtls://<hostname>:<port>[?<options>]
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values.
Options can also can be specified via command line options (or in code via "AVOption"s).
DTLS shares most options with TLS, but operates over UDP instead of TCP.
The list of supported options follows.
ca_file,cafile=filename โ a file containing certificate authority (CA) root certificates to treat as trusted. If the linked TLS library contains a default this might not need to be specified for verification to work, but not all libraries and setups have defaults built in. The file must be in OpenSSL PEM format.tls_verify,verify=1|0โ if enabled, try to verify the peer that we are communicating with. Note, if using OpenSSL, this currently only makes sure that the peer certificate is signed by one of the root certificates in the CA database, but it does not validate that the certificate actually matches the host name we are trying to connect to. This is disabled by default since it requires a CA database to be provided by the caller in many cases.cert_file,cert=filename โ a file containing a certificate to use in the handshake with the peer. (When operating as server, in listen mode, this is more often required by the peer, while client certificates only are mandated in certain setups.)key_file,key=filename โ a file containing the private key for the certificate.cert_pem=string โ Certificate PEM string.key_pem=string โ Private key PEM string.listen=1|0โ if enabled, listen for connections on the provided port, and assume the server role in the handshake instead of the client role.mtu=size โ set the Maximum Transmission Unit (MTU) for DTLS packets.use_srtp=1|0โ enable theuse_srtpDTLS extension. This is used in WebRTC applications to establish SRTP encryption keys through the DTLS handshake. Default is disabled.external_sock=1|0โ use an external socket instead of creating a new one. This option only makes sense to pass when interacting with the code via API โ enabling this from CLI will cause immediate failure ๐. Default is disabled.
Example command lines:
To create a DTLS server:
ffmpeg -listen 1 -i dtls://<hostname>:<port> <output>
To create a DTLS client and send data to server:
ffmpeg -i <input> -f <format> dtls://<hostname>:<port>
udp
User Datagram Protocol ๐ the one that just fires packets into the void and hopes for the best.
The required syntax for an UDP URL is:
udp://<hostname>:<port>[?<options>]
options contains a list of &-separated options of the form key=val. Standard percent-encoding (and using the plus sign for space) can be used to escape keys and values.
Options can also can be specified via command line options (or in code via "AVOption"s).
In case threading is enabled on the system, a circular buffer is used to store the incoming data, which allows one to reduce loss of data due to UDP socket buffer overruns. The fifo_size and overrun_nonfatal options are related to this buffer.
The list of supported options follows.
buffer_size=size โ set the UDP maximum socket buffer size in bytes. This is used to set either the receive or send buffer size, depending on what the socket is used for. Default is 32 KB for output, 384 KB for input. See alsofifo_size.bitrate=bitrate โ if set to nonzero, the output will have the specified constant bitrate if the input has enough packets to sustain it.burst_bits=bits โ when using bitrate this specifies the maximum number of bits in packet bursts.localport=port โ override the local UDP port to bind with.localaddr=addr โ local IP address of a network interface used for sending packets or joining multicast groups.pkt_size=size โ set the size in bytes of UDP packets.reuse=1|0โ explicitly allow or disallow reusing UDP sockets.ttl=ttl โ set the time to live value (for multicast only).dscp=dscp โ set the 6-bit DSCP field for outgoing packets.connect=1|0โ initialize the UDP socket withconnect(). In this case, the destination address can't be changed withff_udp_set_remote_urllater. If the destination address isn't known at the start, this option can be specified inff_udp_set_remote_url, too. This allows finding out the source address for the packets withgetsockname, and makes writes return withAVERROR(ECONNREFUSED)if "destination unreachable" is received. For receiving, this gives the benefit of only receiving packets from the specified peer address/port.sources=address[,address] โ only receive packets sent from the specified addresses. In case of multicast, also subscribe to multicast traffic coming from these addresses only.block=address[,address] โ ignore packets sent from the specified addresses. In case of multicast, also exclude the source addresses in the multicast subscription.fifo_size=units โ set the UDP receiving circular buffer size, expressed as a number of packets with size of 188 bytes. If not specified defaults to7*4096.overrun_nonfatal=1|0โ survive in case of UDP receiving circular buffer overrun. Default value is0.timeout=microseconds โ set raise error timeout, expressed in microseconds. This option is only relevant in read mode: if no data arrived in more than this time interval, raise error.broadcast=1|0โ explicitly allow or disallow UDP broadcasting.
Note that broadcasting may not work properly on networks having a broadcast storm protection. โ ๏ธ
Examples
- Use
ffmpegto stream over UDP to a remote endpoint:
ffmpeg -i <input> -f <format> udp://<hostname>:<port>
- Use
ffmpegto stream in mpegts format over UDP using 188 sized UDP packets, using a large input buffer:
ffmpeg -i <input> -f mpegts udp://<hostname>:<port>?pkt_size=188&buffer_size=65535
- Use
ffmpegto receive over UDP from a remote endpoint:
ffmpeg -i udp://[<multicast-address>]:<port> ...
unix
Unix local socket โ no network, just the machine talking to itself, main character energy honestly. โจ
The required syntax for a Unix socket URL is:
unix://<filepath>
The following parameters can be set via command line options (or in code via "AVOption"s):
timeoutโ timeout in ms.listenโ create the Unix socket in listening mode.typeโ select socket type.streamโ corresponds toSOCK_STREAM(reliable stream-oriented)datagramโ corresponds toSOCK_DGRAM(unreliable packet-oriented)seqpacketโ corresponds toSOCK_SEQPACKET(reliable packet-oriented)
pkt_sizeโ maximum packet size for packet-oriented sockets (SOCK_DGRAMandSOCK_SEQPACKET). If greater than zero, this value is used as"max_packet_size". Ignored forSOCK_STREAM. Default is0.
zmq
ZeroMQ asynchronous messaging using the libzmq library. ๐ซถ
This library supports unicast streaming to multiple clients without relying on an external server.
The required syntax for streaming or connecting to a stream is:
zmq:tcp://ip-address:port
Example: Create a localhost stream on port 5555:
ffmpeg -re -i input -f mpegts zmq:tcp://127.0.0.1:5555
Multiple clients may connect to the stream using:
ffplay zmq:tcp://127.0.0.1:5555
Streaming to multiple clients is implemented using a ZeroMQ Pub-Sub pattern. The server side binds to a port and publishes data. Clients connect to the server (via IP address/port) and subscribe to the stream. The order in which the server and client start generally does not matter.
ffmpeg must be compiled with the --enable-libzmq option to support this protocol.
Options can be set on the ffmpeg/ffplay command line. The following options are supported:
pkt_sizeโ this one forces the max packet size for sending/receiving data. Default is131,072bytes, bestie. On the server side it sets the biggest packet you can send via ZeroMQ; on the clients it sets an internal buffer size for receiving packets. โ ๏ธ and listen โpkt_sizeon the clients should be equal to or greater thanpkt_sizeon the server, otherwise your received message may get truncated and that causes decoding errors. no cap, keep them matched. ๐
๐ DEVICE OPTIONS ๐
Okay so the libavdevice library gives you literally the exact same interface as libavformat. Like, an input device is treated like a demuxer and an output device like a muxer, and the interface + generic device options are the same ones libavformat provides (go peek at the ffmpeg-formats manual, iykyk).
On top of that, each input or output device may support its own little private options that are specific to that component. โจ
You can set options by specifying -option value in the FFmpeg tools, or by setting the value explicitly in the device AVFormatContext options, or by using the libavutil/opt.h API if you're doing it programmatically. ๐ซถ
๐ฆ INPUT DEVICES ๐ฆ
Input devices are these configured elements in FFmpeg that let you access data coming from a multimedia device attached to your system. main character energy honestly.
When you configure your FFmpeg build, all the supported input devices are enabled by default. You can list all the available ones using the configure option --list-indevs. ๐
You can disable all input devices with the configure option --disable-indevs, and selectively enable one with --enable-indev=INDEV, or you can disable a particular input device with --disable-indev=INDEV. choose your own adventure, bestie.
The -devices option of the ff* tools will display the list of supported input devices. ๐
A description of the currently available input devices follows. let's gooo ๐
๐ธ alsa ๐ธ
ALSA (Advanced Linux Sound Architecture) input device. iconic.
To enable this input device during configuration you need libasound installed on your system.
This device lets you capture from an ALSA device. The name of the device to capture has to be an ALSA card identifier.
An ALSA identifier has the syntax:
hw:<CARD>[,<DEV>[,<SUBDEV>]]
where the DEV and SUBDEV components are optional. ๐
The three arguments (in order: CARD, DEV, SUBDEV) specify card number or identifier, device number and subdevice number (-1 means any).
To see the list of cards currently recognized by your system, check the files /proc/asound/cards and /proc/asound/devices. ๐
For example, to capture with ffmpeg from an ALSA device with card id 0, you may run the command:
ffmpeg -f alsa -i hw:0 alsaout.wav
For more information see: <http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html>
Options
sample_rateโ set the sample rate in Hz. Default is48000. ๐ซchannelsโ set the number of channels. Default is2.
๐ง android_camera ๐ง
Android camera input device.
This input device uses the Android Camera2 NDK API, which is available on devices with API level 24+. The availability of android_camera is autodetected during configuration. โจ
This device lets you capture from all the cameras on an Android device that are integrated into the Camera2 NDK API.
The available cameras are enumerated internally and can be selected with the camera_index parameter. The input file string is discarded, literally just thrown away. ๐
Generally the back facing camera has index 0 while the front facing camera has index 1. (front cam = selfie cam, you're welcome ๐ธ)
Options
video_sizeโ set the video size given as a string such as640x480orhd720. Falls back to the first available configuration reported by Android if the requested video size is not available or by default.framerateโ set the video framerate. Falls back to the first available configuration reported by Android if the requested framerate is not available or by default (-1).camera_indexโ set the index of the camera to use. Default is0.input_queue_sizeโ set the maximum number of frames to buffer. Default is5.
๐ avfoundation ๐
AVFoundation input device.
AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >= 10.7 as well as on iOS. ๐
The input filename has to be given in the following syntax:
-i "[[VIDEO]:[AUDIO]]"
The first entry selects the video input while the latter selects the audio input. The stream has to be specified by the device name or the device index as shown by the device list. Alternatively, the video and/or audio input device can be chosen by index using the
-video_device_index <INDEX>
and/or
-audio_device_index <INDEX>
, overriding any device name or index given in the input filename. ๐
All available devices can be enumerated by using -list_devices true, listing all device names and corresponding indices. ๐ฅ
There are two device name aliases:
"default"โ select the AVFoundation default device of the corresponding type."none"โ do not record the corresponding media type. This is equivalent to specifying an empty device name or index. ๐
Options
AVFoundation supports the following options:
-list_devices <TRUE|FALSE>โ if set to true, a list of all available input devices is given showing all device names and indices.-video_device_index <INDEX>โ specify the video device by its index. Overrides anything given in the input filename.-audio_device_index <INDEX>โ specify the audio device by its index. Overrides anything given in the input filename.-pixel_format <FORMAT>โ request the video device to use a specific pixel format. If the specified format is not supported, a list of available formats is given and the first one in this list is used instead. Available pixel formats are:
monob, rgb555be, rgb555le, rgb565be, rgb565le,
rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16,
yuv422p10, yuv444p10,
yuv420p, nv12, yuyv422, gray
-framerateโ set the grabbing frame rate. Default is"ntsc", corresponding to a frame rate of30000/1001. ๐ธ-video_sizeโ set the video frame size.-capture_cursorโ capture the mouse pointer. Default is0.-capture_mouse_clicksโ capture the screen mouse clicks. Default is0.-capture_raw_dataโ capture the raw device data. Default is0. Using this option may result in receiving the underlying data delivered to the AVFoundation framework. E.g. for muxed devices that send raw DV data to the framework (like tape-based camcorders), setting this option to false results in extracted video frames captured in the designated pixel format only. Setting this option to true results in receiving the raw DV stream untouched. ๐ฅ
Examples
- Print the list of AVFoundation supported devices and exit:
$ ffmpeg -f avfoundation -list_devices true -i ""
- Record video from video device
0and audio from audio device0intoout.avi:
$ ffmpeg -f avfoundation -i "0:0" out.avi
- Record video from video device
2and audio from audio device1intoout.avi:
$ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
- Record video from the system default video device using the pixel format
bgr0and do not record any audio intoout.avi:
$ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
- Record raw DV data from a suitable input device and write the output into
out.dv:
$ ffmpeg -f avfoundation -capture_raw_data true -i "zr100:none" out.dv
๐ decklink ๐
The decklink input device provides capture capabilities for Blackmagic DeckLink devices. ๐ฌ
To enable this input device, you need the Blackmagic DeckLink SDK and you need to configure with the appropriate --extra-cflags and --extra-ldflags. On Windows, you need to run the IDL files through widl. (not me having to explain widl to you, just trust the process ๐ญ)
DeckLink is very picky about the formats it supports. fr fr, it's giving diva. The pixel format of the input can be set with raw_format. Framerate and video size must be determined for your device with -list_formats 1. Audio sample rate is always 48 kHz and the number of channels can be 2, 8 or 16. Note that all audio channels are bundled in one single audio track. ๐
Options
list_devicesโ if set to true, print a list of devices and exit. Defaults tofalse. โ ๏ธ This option is deprecated, please use the-sourcesoption offfmpegto list the available input devices.list_formatsโ if set to true, print a list of supported formats and exit. Defaults tofalse.format_code <FourCC>โ this sets the input video format to the format given by the FourCC. To see the supported values of your device(s) uselist_formats. Note that there is a FourCC'pal 'that can also be used aspal(3 letters). Default behavior is autodetection of the input video format, if the hardware supports it. ๐ซraw_formatโ set the pixel format of the captured video. Available values are:autoโ this is the default which means 8-bit YUV 422 or 8-bit ARGB if format autodetection is used, 8-bit YUV 422 otherwise.uyvy422โ 8-bit YUV 422.yuv422p10โ 10-bit YUV 422.argbโ 8-bit RGB.bgraโ 8-bit RGB.rgb10โ 10-bit RGB.
teletext_linesโ if set to nonzero, an additional teletext stream will be captured from the vertical ancillary data. Both SD PAL (576i) and HD (1080i or 1080p) sources are supported. In case of HD sources, OP47 packets are decoded. ๐บ
This option is a bitmask of the SD PAL VBI lines captured, specifically lines 6 to 22, and lines 318 to 335. Line 6 is the LSB in the mask. Selected lines which do not contain teletext information will be ignored. You can use the special all constant to select all possible lines, or standard to skip lines 6, 318 and 319, which are not compatible with all receivers.
For SD sources, ffmpeg needs to be compiled with --enable-libzvbi. For HD sources, on older (pre-4K) DeckLink card models you have to capture in 10 bit mode. โ ๏ธ
channelsโ defines number of audio channels to capture. Must be2,8or16. Defaults to2.duplex_modeโ sets the decklink device duplex/profile mode. Must beunset,half,full,one_sub_device_full,one_sub_device_half,two_sub_device_full,four_sub_device_half. Defaults tounset. ๐ฆ
๐ก Heads up, bestie: DeckLink SDK 11.0 have replaced the duplex property by a profile property. For the DeckLink Duo 2 and DeckLink Quad 2, a profile is shared between any 2 sub-devices that utilize the same connectors. For the DeckLink 8K Pro, a profile is shared between all 4 sub-devices. So DeckLink 8K Pro support four profiles.
Valid profile modes for DeckLink 8K Pro (with DeckLink SDK >= 11.0): one_sub_device_full, one_sub_device_half, two_sub_device_full, four_sub_device_half
Valid profile modes for DeckLink Quad 2 and DeckLink Duo 2: half, full
timecode_formatโ the timecode type to include in the frame and video stream metadata. Has to be one ofnone,rp188vitc,rp188vitc2,rp188ltc,rp188hfr,rp188any,vitc,vitc2, orserial. Defaults tonone, aka literally not included at all ๐
Fr fr, to properly support 50/60 fps timecodes, the ordering of the queried timecode types for rp188any is HFR, VITC1, VITC2 and LTC for >30 fps content. And note that this is slightly different to the ordering used by the DeckLink API, which is HFR, VITC1, LTC, VITC2 โ so don't @ me, that's just how it is ๐ซ
video_inputโ sets the video input source. Must beunset,sdi,hdmi,optical_sdi,component,compositeors_video. Defaults tounset.audio_inputโ sets the audio input source. Must beunset,embedded,aes_ebu,analog,analog_xlr,analog_rcaormicrophone. Defaults tounset.video_ptsโ sets the video packet timestamp source. Must bevideo,audio,reference,wallclockorabs_wallclock. Defaults tovideo.audio_ptsโ sets the audio packet timestamp source. Must bevideo,audio,reference,wallclockorabs_wallclock. Defaults toaudio.draw_barsโ if set totrue, color bars are drawn in the event of a signal loss. Defaults totrue. โ ๏ธ This option is deprecated, please use thesignal_loss_actionoption instead!signal_loss_actionโ sets the action to take in the event of a signal loss. Accepts one of the following values:1,noneโ do nothing on signal loss. This usually results in black frames ๐ค2,barsโ draw color bars on signal loss. Only supported for 8-bit input signals.3,repeatโ repeat the last video frame on signal loss ๐
Defaults to bars.
queue_sizeโ sets maximum input buffer size in bytes. If the buffering reaches this value, incoming frames will be dropped. Defaults to1073741824.audio_depthโ sets the audio sample bit depth. Must be16or32. Defaults to16.decklink_copytsโ if set totrue, timestamps are forwarded as they are without removing the initial offset. Defaults tofalse.timestamp_alignโ capture start time alignment in seconds. If set to nonzero, input frames are dropped till the system timestamp aligns with configured value. Alignment difference of up to one frame duration is tolerated. This is useful for maintaining input synchronization across N different hardware devices deployed for 'N-way' redundancy. The system time of different hardware devices should be synchronized with protocols such as NTP or PTP, before using this option.
โ ๏ธ Note that this method is not foolproof. In some border cases input synchronization may not happen due to thread scheduling jitters in the OS. Either sync could go wrong by 1 frame or in a rarer casetimestamp_alignseconds. Defaults to0.
wait_for_tc(bool) โ drop frames till a frame with timecode is received. Sometimes serial timecode isn't received with the first input frame, and if that happens, the stored stream timecode will be inaccurate ๐ญ If this option is set totrue, input frames are dropped till a frame with timecode is received. Optiontimecode_formatmust be specified. Defaults tofalse.enable_klv(bool)โ if set totrue, extracts KLV data from VANC and outputs KLV packets. KLV VANC packets are joined based on MID and PSC fields and aggregated into one KLV packet. Defaults tofalse.
โจ Examples โจ
- List input devices, iconic behaviour honestly:
ffmpeg -sources decklink
- List supported formats:
ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
- Capture video clip at 1080i50:
ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
- Capture video clip at 1080i50 10 bit:
ffmpeg -raw_format yuv422p10 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
- Capture video clip at 1080i50 with 16 audio channels:
ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
๐ฌ dshow
Windows DirectShow input device. Yes, we're on Windows now, buckle up ๐ช
DirectShow support is enabled when FFmpeg is built with the mingw-w64 project. Currently only audio and video devices are supported.
Multiple devices may be opened as separate inputs, but they may also be opened on the same input, which should improve synchronism between them ๐ฏ
The input name should be in the format:
<TYPE>=<NAME>[:<TYPE>=<NAME>]
where TYPE can be either audio or video, and NAME is the device's name or alternative name..
Options
If no options are specified, the device's defaults are used. If the device does not support the requested options, it will fail to open. That's it, that's the deal ๐ซถ
video_sizeโ set the video size in the captured video.framerateโ set the frame rate in the captured video.sample_rateโ set the sample rate (in Hz) of the captured audio.sample_sizeโ set the sample size (in bits) of the captured audio.channelsโ set the number of channels in the captured audio.list_devicesโ if set totrue, print a list of devices and exit.list_optionsโ if set totrue, print a list of selected device's options and exit.video_device_numberโ set video device number for devices with the same name (starts at0, defaults to0).audio_device_numberโ set audio device number for devices with the same name (starts at0, defaults to0).pixel_formatโ select pixel format to be used by DirectShow. This may only be set when the video codec is not set or set torawvideo.audio_buffer_sizeโ set audio device buffer size in milliseconds (which can directly impact latency, depending on the device). Defaults to using the audio device's default buffer size (typically some multiple of500ms). Setting this value too low can degrade performance ๐ฅด See also <http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx>video_pin_nameโ select video capture pin to use by name or alternative name.audio_pin_nameโ select audio capture pin to use by name or alternative name.crossbar_video_input_pin_numberโ select video input pin number for crossbar device. This will be routed to the crossbar device's Video Decoder output pin. Note that changing this value can affect future invocations (sets a new default) until system reboot occurs. โ ๏ธ Like, it literally sticks around, bestie.crossbar_audio_input_pin_numberโ select audio input pin number for crossbar device. This will be routed to the crossbar device's Audio Decoder output pin. Note that changing this value can affect future invocations (sets a new default) until system reboot occurs.show_video_device_dialogโ if set totrue, before capture starts, popup a display dialog to the end user, allowing them to change video filter properties and configurations manually. Note that for crossbar devices, adjusting values in this dialog may be needed at times to toggle between PAL (25 fps) and NTSC (29.97) input frame rates, sizes, interlacing, etc. Changing these values can enable different scan rates/frame rates and avoiding green bars at the bottom, flickering scan lines, etc. Note that with some devices, changing these properties can also affect future invocations (sets new defaults) until system reboot occurs ๐ซshow_audio_device_dialogโ if set totrue, before capture starts, popup a display dialog to the end user, allowing them to change audio filter properties and configurations manually.show_video_crossbar_connection_dialogโ if set totrue, before capture starts, popup a display dialog to the end user, allowing them to manually modify crossbar pin routings, when it opens a video device.show_audio_crossbar_connection_dialogโ if set totrue, before capture starts, popup a display dialog to the end user, allowing them to manually modify crossbar pin routings, when it opens an audio device.show_analog_tv_tuner_dialogโ if set totrue, before capture starts, popup a display dialog to the end user, allowing them to manually modify TV channels and frequencies.show_analog_tv_tuner_audio_dialogโ if set totrue, before capture starts, popup a display dialog to the end user, allowing them to manually modify TV audio (like mono vs. stereo, Language A,B or C).audio_device_loadโ load an audio capture filter device from file instead of searching it by name. It may load additional parameters too, if the filter supports the serialization of its properties to. To use this an audio capture source has to be specified, but it can be anything even fake one ๐audio_device_saveโ save the currently used audio capture filter device and its parameters (if the filter supports it) to a file. If a file with the same name exists it will be overwritten.video_device_loadโ load a video capture filter device from file instead of searching it by name. It may load additional parameters too, if the filter supports the serialization of its properties to. To use this a video capture source has to be specified, but it can be anything even fake one.video_device_saveโ save the currently used video capture filter device and its parameters (if the filter supports it) to a file. If a file with the same name exists it will be overwritten.use_video_device_timestampsโ if set tofalse, the timestamp for video frames will be derived from the wallclock instead of the timestamp provided by the capture device. This allows working around devices that provide unreliable timestamps ๐ฐ๏ธ
โจ Examples โจ
- Print the list of DirectShow supported devices and exit:
$ ffmpeg -list_devices true -f dshow -i dummy
- Open video device Camera:
$ ffmpeg -f dshow -i video="Camera"
- Open second video device with name Camera:
- Open video device Camera with the second video device number:
$ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
- Open video device Camera and audio device Microphone at the same time, iconic combo:
$ ffmpeg -f dshow -i video="Camera":audio="Microphone"
- Print every supported option on the selected device and then dip out:
$ ffmpeg -list_options true -f dshow -i video="Camera"
- Name your pins by name or alternative name, and pick a device by its alternative name too (yes the string is that long, don't @ me):
$ ffmpeg -f dshow -audio_pin_name "Audio Out" -video_pin_name 2 -i video=video="@device_pnp_\\?\pci#ven_1a0a&dev_6200&subsys_62021461&rev_01#4&e2c7dd6&0&00e1#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\{ca465100-deb0-4d59-818f-8c477184adf6}":audio="Microphone"
- Set up a crossbar device, pick the crossbar pins, and let the user tweak video capture properties at startup:
$ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
-crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
๐ผ๏ธ fbdev
The Linux framebuffer input device ๐
So the Linux framebuffer is this graphic hardwareโindependent abstraction layer that puts graphics on your monitor โ usually on the console. You get to it through a file device node, and that's usually /dev/fb0.
Want the full lore? Go read the file Documentation/fb/framebuffer.txt in the Linux source tree. It's giving documentation realness.
Also check out <http://linux-fbdev.sourceforge.net/>, and fbset(1).
To record from that framebuffer device /dev/fb0 with ffmpeg:
ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
And you can absolutely grab a single screenshot image with:
ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
Options
framerateโ sets the frame rate. Default is25โจ
๐ช gdigrab
The Win32 GDIโbased screen capture device ๐ฅ๏ธ
This one lets you capture a region of your display on Windows. Love that for us.
The input filename can be a few different things, like:
desktop
or
title=<window_title>
or
hwnd=<window_hwnd>
The first option grabs the entire desktop, or a fixed region of the desktop. The second and third options instead capture the contents of a single window โ doesn't matter where it is on screen, it's getting grabbed ๐
For example, to grab the whole desktop using ffmpeg:
ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
Grab a 640x480 region at position "10,20":
ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
Grab the contents of the window named "Calculator":
ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
Options
draw_mouseโ specifies whether to draw the mouse pointer. Use the value0to not draw the pointer. Default value is1๐ฑ๏ธframerateโ sets the grabbing frame rate. Default value is"ntsc", which corresponds to a frame rate of"30000/1001".show_regionโ shows the grabbed region on screen.
If show_region is specified with 1, then the grabbing region will be indicated on screen. With this option it's super easy to see what's actually being grabbed if you're only grabbing a portion of the screen.
Heads up bestie: show_region is incompatible with grabbing the contents of a single window ๐
For example:
ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
video_sizeโ sets the video frame size. Default is to capture the full screen ifdesktopis selected, or the full window size iftitle=window_titleis selected.offset_xโ when capturing a region withvideo_size, this sets the distance from the left edge of the screen or desktop.
Note that the offset calculation is from the top left corner of the primary monitor on Windows. If you've got a monitor positioned to the left of your primary monitor, you'll need to use a negative offset_x value to move the region over to that monitor ๐
offset_yโ when capturing a region withvideo_size, this sets the distance from the top edge of the screen or desktop.
Note that the offset calculation is from the top left corner of the primary monitor on Windows. If you've got a monitor positioned above your primary monitor, you'll need to use a negative offset_y value to move the region up to that monitor ๐ซถ
๐ฅ iec61883
FireWire DV/HDV input device using libiec61883 ๐ฅ
To enable this input device you need libiec61883, libraw1394 and libavc1394 installed on your system. Use the configure option --enable-libiec61883 to compile with the device enabled.
The iec61883 capture device supports capturing from a video device connected via IEEE1394 (FireWire), using libiec61883 and the new Linux FireWire stack (juju). This is the default DV/HDV input method in Linux Kernel 2.6.37 and later, since the old FireWire stack got removed. Rip old stack ๐ชฆ
Specify the FireWire port to be used as the input file, or "auto" to choose the first port that's connected.
Options
dvtypeโ overrides autodetection of DV/HDV. This should only be used if auto detection doesn't work, or if using a different device type should be prohibited.
Real talk: treating a DV device as HDV (or vice versa) will not work and will result in undefined behavior ๐ญ
The values auto, dv and hdv are supported.
dvbufferโ sets the maximum size of the buffer for incoming data, in frames. For DV this is an exact value. For HDV it's not frame exact, since HDV doesn't have a fixed frame size. It's giving "close enough".dvguidโ selects the capture device by specifying its GUID. Capturing will only happen from the specified device, and it fails if no device with the given GUID is found. This is useful for selecting the input when multiple devices are connected at the same time. Peep/sys/bus/firewire/devicesto find out the GUIDs ๐
Examples
- Grab and show the input of a FireWire DV/HDV device:
ffplay -f iec61883 -i auto
- Grab and record the input of a FireWire DV/HDV device, using a packet buffer of
100000packets if the source is HDV:
ffmpeg -f iec61883 -i auto -dvbuffer 100000 out.mpg
๐ง jack
The JACK input device ๐ถ
To enable this input device during configuration you need libjack installed on your system.
A JACK input device creates one or more JACK writable clients, one for each audio channel, with the name client_name:input_N, where client_name is the name provided by the application, and N is a number that identifies the channel. Each writable client sends the acquired data to the FFmpeg input device.
Once you've created one or more JACK readable clients, you need to connect them to one or more JACK writable clients.
To connect or disconnect JACK clients you can use the jack_connect and jack_disconnect programs, or do it through a graphical interface โ for example with qjackctl.
To list the JACK clients and their properties you can invoke the command jack_lsp.
Here's an example showing how to capture a JACK readable client with ffmpeg:
# Create a JACK writable client with name "ffmpeg".
$ ffmpeg -f jack -i ffmpeg -y out.wav
# Start the sample jack_metro readable client.
$ jack_metro -b 120 -d 0.2 -f 4000
# List the current JACK clients.
$ jack_lsp -c
system:capture_1
system:capture_2
system:playback_1
system:playback_2
ffmpeg:input_1
metro:120_bpm
# Connect metro to the ffmpeg writable client.
$ jack_connect metro:120_bpm ffmpeg:input_1
Want more? Read: <http://jackaudio.org/>
Options
channelsโ sets the number of channels. Default is2๐๏ธ
๐ฅ๏ธ kmsgrab
The KMS video input device โจ
Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a DRM object that can be passed to other hardware functions. Very main character energy.
Requires either DRM master or CAP_SYS_ADMIN to run.
If you don't understand what all of that means, you probably don't want this. Look at x11grab instead ๐
Options
deviceโ the DRM device to capture on. Defaults to/dev/dri/card0.formatโ pixel format of the framebuffer. This can be autodetected if you're running Linux 5.7 or later, but it needs to be provided for earlier versions. Defaults tobgr0, which is the most common format used by the Linux console and Xorg X server.format_modifierโ format modifier to signal on output frames. This is necessary to import correctly into some APIs. It can be autodetected if you're running Linux 5.7 or later, but will need to be provided explicitly when needed in earlier versions. See thelibdrmdocumentation for possible values ๐crtc_idโ KMS CRTC ID to define the capture source. The first active plane on the given CRTC will be used.plane_idโ KMS plane ID to define the capture source. Defaults to the first active plane found if neithercrtc_idnorplane_idare specified.framerateโ framerate to capture at. This is not synchronised to any page flipping or framebuffer changes โ it just defines the interval at which the framebuffer is sampled. Sampling faster than the framebuffer update rate will generate independent frames with the same content. Defaults to30.
Examples
- Capture from the first active plane, download the result to normal frames and encode. This will only work if the framebuffer is both linear and mappable โ if not, the result may be scrambled or fail to download ๐ฌ
ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
- Capture from CRTC ID
42at 60fps, map the result to VAAPI, convert to NV12 and encode as H.264:
ffmpeg -crtc_id 42 -framerate 60 -f kmsgrab -i - -vf 'hwmap=derive_device=vaapi,scale_vaapi=w=1920:h=1080:format=nv12' -c:v h264_vaapi output.mp4
- Want only part of a plane? The output can be cropped โ this can be used to capture a single window, as long as it has a known absolute position and size. For example, to capture and encode the middle quarter of a
1920x1080plane:
ffmpeg -f kmsgrab -i - -vf 'hwmap=derive_device=vaapi,crop=960:540:480:270,scale_vaapi=960:540:nv12' -c:v h264_vaapi output.mp4
๐ง lavfi
The Libavfilter input virtual device ๐ฆ
This input device reads data from the open output pads of a libavfilter filtergraph.
For each filtergraph open output, the input device will create a corresponding stream which is mapped to the generated output. The filtergraph is specified through the option graph.
Options
graph
Okay so this is the big one โ bestie, this is how you tell lavfi exactly what filtergraph to use as input. Every video open output has to be labelled with a unique string of the form "outN", where N is a number starting from 0 that corresponds to the mapped input stream the device generates. The first unlabelled output? It automatically gets the "out0" label. But all the others โ every single one โ have to be written out explicitly. No shortcuts, sorry babe ๐
And there's this extra little sprinkle: you can tack the suffix "+subcc" onto an output label to create an extra stream with the closed captions packets attached to that output (this one's experimental, fyi โ only for EIA-608 / CEA-708 for now). The subcc streams get created after all the normal streams, in the order of the corresponding stream. So like, if there's "out19+subcc", "out7+subcc" and up to "out42", then stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19. Math class but make it video ๐งฎโจ
If you don't specify it at all, it defaults to the filename specified for the input device.
graph_file
Set the filename of the filtergraph to be read and sent to the other filters. The syntax of the filtergraph is exactly the same as the one you'd specify with the graph option. Same vibes, different delivery method ๐
dumpgraph
Dumps the graph to stderr. That's it. That's the whole thing. Diagnostic queen ๐
Examples
- Create a color video stream and play it back with
ffplay:
ffplay -f lavfi -graph "color=c=pink [out0]" dummy
- Same as the previous example, but use the filename to specify the graph description instead, and omit the
"out0"label:
ffplay -f lavfi color=c=pink
- Create three different video test filtered sources and play them all:
ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
- Read an audio stream from a file using the
amoviesource and play it back withffplay:
ffplay -f lavfi "amovie=test.wav"
- Read an audio stream and a video stream and play both back with
ffplay:
ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
- Dump decoded frames to images and Closed Captions to an RCWT backup:
ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rcwt subcc.bin
๐ libcdio
Audio-CD input device, built on top of libcdio. Retro tech, we stan a physical media moment ๐ฟ
To enable this input device during configuration you need libcdio installed on your system โ it requires the configure option --enable-libcdio. No libcdio, no CD party, sorry ๐ซถ
This device lets you play and grab from an Audio-CD, which is honestly iconic.
So like, for example, to copy the entire Audio-CD in /dev/sr0 with ffmpeg, you'd run:
ffmpeg -f libcdio -i /dev/sr0 cd.wav
Options
speed
Set the drive reading speed. Default value is 0.
The speed is specified in CD-ROM speed units. It gets set through the libcdio cdio_cddap_speed_set function. Heads up though: on many CD-ROM drives, if you specify a value that's too large, you'll just end up using the fastest speed. The drive said "I'll do what I want" ๐ญ
paranoia_mode
Set the paranoia recovery mode flags. It accepts one of these values:
disableverifyoverlapneverskipfull
Default value is disable.
For more info about the available recovery modes, go consult the paranoia project documentation. (Yes the mode is literally called paranoia, and no we're not being dramatic for once ๐)
๐ฆ libdc1394
IIDC1394 input device, based on libdc1394 and libraw1394. FireWire girlies rise ๐ฅ
Requires the configure option --enable-libdc1394.
Options
framerate
Set the frame rate. Default is "ntsc", which corresponds to a frame rate of "30000/1001".
pixel_format
Select the pixel format. Default is "uyvy422".
video_size
Set the video size, given as a string such as "640x480" or "hd720". Default is "qvga".
๐ง openal
The OpenAL input device provides audio capture on all systems that have a working OpenAL 1.1 implementation. Cross-platform audio capture, we love to see it โจ
To enable this input device during configuration, you need OpenAL headers and libraries installed on your system, and you need to configure FFmpeg with --enable-openal.
OpenAL headers and libraries should come as part of your OpenAL implementation, or as an additional download (an SDK). Depending on your installation, you may need to specify additional flags via --extra-cflags and --extra-ldflags so the build system can actually locate the OpenAL headers and libraries. Basically you gotta help the compiler find its glasses ๐
Here's an incomplete list of OpenAL implementations:
- Creative โ the official Windows implementation, providing hardware acceleration with supported devices plus a software fallback. See <http://openal.org/>.
- OpenAL Soft โ a portable, open source (LGPL) software implementation. Includes backends for the most common sound APIs on the Windows, Linux, Solaris, and BSD operating systems. See <http://kcat.strangesoft.net/openal.html>.
- Apple โ OpenAL is part of Core Audio, the official Mac OS X Audio interface. See <http://developer.apple.com/technologies/mac/audio-and-video.html>
This device lets you capture from an audio input device that's handled through OpenAL.
You need to specify the name of the device to capture in the filename you provide. If you give it the empty string, the device will automatically select the default device. You can get the list of supported devices by using the list_devices option. Slay ๐
Options
channels
Set the number of channels in the captured audio. Only the values 1 (monaural) and 2 (stereo) are currently supported. Defaults to 2.
sample_size
Set the sample size (in bits) of the captured audio. Only the values 8 and 16 are currently supported. Defaults to 16.
sample_rate
Set the sample rate (in Hz) of the captured audio. Defaults to 44.1k.
list_devices
If set to true, print a list of devices and exit. Defaults to false.
Examples
Print the list of OpenAL supported devices and exit:
$ ffmpeg -list_devices true -f openal -i dummy out.ogg
Capture from the OpenAL device DR-BT101 via PulseAudio:
$ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
Capture from the default device (note the empty string '' as the filename):
$ ffmpeg -f openal -i '' out.ogg
Capture from two devices simultaneously, writing to two different files, all within the same ffmpeg command:
$ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
Note: not all OpenAL implementations support multiple simultaneous capture โ try the latest OpenAL Soft if the above does not work. It's giving "works on my machine" but make it audio ๐ญ
๐ธ oss
Open Sound System input device. Old school, but it's still here and it's still serving ๐ซถ
The filename you provide to the input device is the device node representing the OSS input device, and it's usually set to /dev/dsp.
So like, for example, to grab from /dev/dsp using ffmpeg, use the command:
ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
For more information about OSS see: <http://manuals.opensound.com/usersguide/dsp.html>
Options
sample_rate
Set the sample rate in Hz. Default is 48000.
channels
Set the number of channels. Default is 2.
๐ pulse
PulseAudio input device. The people's audio server, no cap โจ
To enable this output device you need to configure FFmpeg with --enable-libpulse.
The filename you provide to the input device is a source device or the string "default".
To list the PulseAudio source devices and their properties, you can invoke the command pactl list sources. Peek behind the curtain, bestie ๐
More information about PulseAudio can be found on <http://www.pulseaudio.org>.
Options
server
Connect to a specific PulseAudio server, specified by an IP address. The default server is used when this isn't provided.
name
Specify the application name PulseAudio will use when showing active clients. By default it's the "LIBAVFORMAT_IDENT" string.
stream_name
Specify the stream name PulseAudio will use when showing active streams. By default it's "record".
sample_rate
Specify the samplerate in Hz. By default 48kHz is used.
channels
Specify the channels in use. By default 2 (stereo) is set.
frame_size
This option does nothing and is deprecated. It's giving ghost of options past ๐
fragment_size
Specify the size in bytes of the minimal buffering fragment in PulseAudio โ it will affect the audio latency. By default it's set to 50 ms amount of data.
wallclock
Set the initial PTS using the current time. Default is 1.
Examples
Record a stream from the default device:
ffmpeg -f pulse -i default /tmp/pulse.wav
๐ sndio
sndio input device. BSD besties, this one's for you ๐
To enable this input device during configuration you need libsndio installed on your system.
The filename you provide to the input device is the device node representing the sndio input device, and it's usually set to /dev/audio0.
So like, for example, to grab from /dev/audio0 using ffmpeg, use the command:
ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
Options
sample_rate
Set the sample rate in Hz. Default is 48000.
channels
Set the number of channels. Default is 2.
๐ video4linux2, v4l2
Video4Linux2 input video device. Webcam girlies, this is your moment ๐ทโจ
"v4l2" can be used as an alias for "video4linux2". Cute nickname, same device.
If FFmpeg is built with v4l-utils support (by using the --enable-libv4l2 configure option), it's possible to use it with the -use_libv4l2 input device option.
The name of the device to grab is a file device node โ usually Linux systems tend to automatically create such nodes when the device (e.g. a USB webcam) is plugged into the system, and it has a name of the kind /dev/videoN, where N is a number associated with the device.
Video4Linux2 devices usually support a limited set of widthx*height* sizes and frame rates. You can check which ones are supported using -list_formats all for Video4Linux2 devices. Some devices, like TV cards, support one or more standards too, and it's possible to list all the supported standards using -list_standards all.
The time base for the timestamps is 1 microsecond. Depending on the kernel version and configuration, the timestamps may be derived from the real time clock (origin at the Unix Epoch) or the monotonic clock (origin usually at boot time, unaffected by NTP or manual changes to the clock). The -timestamps abs or -ts abs option can be used to force conversion into the real time clock. Timezone drama but make it kernel-level ๐ญ
Some usage examples of the video4linux2 device with ffmpeg and ffplay:
- List supported formats for a video4linux2 device:
ffplay -f video4linux2 -list_formats all /dev/video0
- Grab and show the input of a video4linux2 device:
ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
- Grab and record the input of a video4linux2 device, leaving the frame rate and size as previously set:
ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
For more information about Video4Linux, check <http://linuxtv.org/>.
Options
standardโ sets the standard, bestie. Has to be the name of a standard that's actually supported, so don't just make one up ๐. Wanna see the whole menu of supported standards? Hit up thelist_standardsoption.channelโ the input channel number. Defaults to-1, which lowkey just means "use whatever channel we already picked" ๐ซถ.video_sizeโ sets the video frame size. The argument's gotta be a string shaped likeWIDTHxHEIGHT, or one of those valid size abbreviations โจ.pixel_formatโ picks the pixel format. Heads up: this only works for raw video input ๐.input_formatโ sets the preferred pixel format (for raw video) or a codec name. It's giving "let me choose", because this option lets you select the input format when several of them are available. Options, options ๐ .framerateโ sets the preferred video frame rate. Simple, iconic, no notes.list_formatsโ lists all the available formats (that's supported pixel formats, codecs, and frame sizes, bestie) and then dips out โexit. The values it takes are:allโ show all the available formats, compressed and non-compressed alike ๐.rawโ show only raw video (non-compressed) formats.compressedโ show only the compressed formats. Periodt.
list_standardsโ lists the supported standards and exits, bye ๐. Values:allโ show all supported standards.
timestamps,tsโ sets the type of timestamps for grabbed frames โฐ. Values:defaultโ use the timestamps straight from the kernel.absโ absolute timestamps (wall clock, like, actual time o'clock ๐ฐ๏ธ).mono2absโ forces a conversion from monotonic to absolute timestamps.
The default value is "default", obviously ๐.
use_libv4l2โ uses libv4l2 (v4l-utils) conversion functions. Default is0, so it's off unless you say otherwise.
๐ vfwcap
The VfW (Video for Windows) capture input device. Retro vibes ๐ฆ.
The filename you pass as input is literally the capture driver number, ranging from 0 to 9. And yes, you may use "list" as the filename to print out a list of drivers โ so helpful of it ๐ญ. Any other filename gets interpreted as device number 0, no cap.
Options
video_sizeโ sets the video frame size. That's it, that's the whole job ๐ .framerateโ sets the grabbing frame rate. Default value is"ntsc", which corresponds to a frame rate of"30000/1001". Math girlies rise ๐ง.
๐ธ x11grab
The X11 video input device โ screen capture icon behavior ๐
To even enable this input device during configuration you need libxcb installed on your system. Good news: it gets automatically detected during configuration, so she'll find it herself โจ.
This device lets you capture a region of an X11 display. Main character energy fr fr.
The filename you pass as input has this syntax:
[<hostname>]:<display_number>.<screen_number>[+<x_offset>,<y_offset>]
hostname:display_number.screen_number specifies the X11 display name of the screen you're grabbing from. hostname can be omitted, and it defaults to "localhost". Also, the environment variable DISPLAY contains the default display name, iykyk ๐.
x_offset and y_offset specify the offsets of the grabbed area with respect to the top-left border of the X11 screen. They default to 0.
Check the X11 documentation (like, man X) for more detailed info โ she has lore ๐.
Use the xdpyinfo program for getting the basic info about the properties of your X11 display (e.g. grep for "name" or "dimensions"). Lowkey a lifesaver.
For example, to grab from :0.0 using ffmpeg:
ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
And to grab at position "10,20":
ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
Options
select_regionโ specify whether to select the grabbing area graphically using the pointer ๐ฑ๏ธ. A value of1prompts the user to select the grabbing area graphically by clicking and dragging. A single click with no dragging will select the whole screen. A region with zero width or height will also select the whole screen. This option overwrites thevideo_size,grab_x, andgrab_yoptions. Default value is0. (She's a little bossy but we love her ๐ )draw_mouseโ specify whether to draw the mouse pointer. A value of0says nope, don't draw the pointer. Default value is1.follow_mouseโ makes the grabbed area follow the mouse ๐ญ. The argument can be"centered"or a number of pixels, PIXELS.
When you specify it with "centered", the grabbing region follows the mouse pointer and keeps the pointer at the center of the region. Otherwise, the region only follows when the mouse pointer reaches within PIXELS (greater than zero) of the edge of the region.
For example:
ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
To follow only when the mouse pointer reaches within 100 pixels to the edge:
ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
framerateโ sets the grabbing frame rate. Default value is"ntsc", corresponding to a frame rate of"30000/1001"โญ.show_regionโ show the grabbed region on screen ๐.
If show_region is specified with 1, then the grabbing region will be indicated on screen. With this option it's super easy to know what's being grabbed if you're only grabbing a portion of the screen. Obsessed with the transparency honestly.
region_borderโ sets the region border thickness if-show_region 1is used. Range is1to128and the default is3(XCB-based x11grab only, bestie โ don't @ me).
For example:
ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
With follow_mouse:
ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
window_idโ grab this window instead of the whole screen ๐ช. Default value is0, which maps to the whole screen (root window).
The id of a window can be found using the xwininfo program, possibly with the options -tree and -root. Detective work but make it cute ๐.
If the window is later enlarged, the new area is not recorded โ she said what she said. Video ends when the window is closed, unmapped (i.e. iconified), or shrunk beyond the video size (which defaults to the initial window size). So like, don't minimize it, babe ๐ญ.
Heads up! This option disables the optionsfollow_mouseandselect_region. Pick a lane ๐.
video_sizeโ sets the video frame size. Default is the full desktop or window.grab_xgrab_yโ set the grabbing region coordinates. They're expressed as an offset from the top-left corner of the X11 window and correspond to thex_offsetandy_offsetparameters in the device name. The default value for both options is0๐.
๐ RESAMPLER OPTIONS ๐
okay so the audio resampler has a whole little family of named options and yes you're gonna learn all of them ๐
Here's how you set them: you can pass -option value in the FFmpeg tools, or option=value for the aresample filter, or set the value explicitly in the SwrContext options, or use the libavutil/opt.h API if you're doing it programmatically. Three ways to the same slay, basically ๐ซถ
uchl,used_chlayoutโ sets the used input channel layout. Default is unset, and it's only used for that special remapping situation โจisr,in_sample_rateโ sets the input sample rate. Default value is0.osr,out_sample_rateโ sets the output sample rate. Default value is0.isf,in_sample_fmtโ specify the input sample format. It gets set by default tonone.osf,out_sample_fmtโ specify the output sample format. Also defaulting tonone.tsf,internal_sample_fmtโ set the internal sample format. Default value isnone. If you don't set it explicitly, it'll get chosen automatically for you, no cap ๐งichl,in_chlayoutandochl,out_chlayoutโ set the input/output channel layout. For the required syntax, go peek at the Channel Layout section in theffmpeg-utils(1)manual ๐clev,center_mix_levelโ set the center mix level. It's a value in deciBel, and it must be in the interval[-32,32]. Like, must must.slev,surround_mix_levelโ set the surround mix level. Also in deciBel, also has to live inside[-32,32].lfe_mix_levelโ sets the LFE mix into non-LFE level. It's used when there's an LFE input but no LFE output. deciBel again, interval[-32,32]again. Consistency is iconic.rmvol,rematrix_volumeโ set the rematrix volume. Default value is1.0.rematrix_maxvalโ set the maximum output value for rematrixing. It's the whole "prevent clipping vs. prevent volume reduction" tradeoff, so pick your fighter. A value of1.0prevents clipping.flags,swr_flagsโ set the flags used by the converter. Default value is0. It supports the following individual flags:resโ force resampling. This flag makes resampling happen even when the input and output sample rates match ๐ฅ
dither_scaleโ set the dither scale. Default value is1.dither_methodโ set the dither method. Default value is0. Supported values are:rectangularโ select rectangular dithertriangularโ select triangular dithertriangular_hpโ select triangular dither with high passlipshitzโ select Lipshitz noise shaping dithershibataโ select Shibata noise shaping ditherlow_shibataโ select low Shibata noise shaping ditherhigh_shibataโ select high Shibata noise shaping ditherf_weightedโ select f-weighted noise shaping dithermodified_e_weightedโ select modified-e-weighted noise shaping ditherimproved_e_weightedโ select improved-e-weighted noise shaping dither
resamplerโ set the resampling engine. Default value isswr. Supported values are:swrโ selects the native SW Resampler; the filter optionsprecisionandchebyare not applicable in this casesoxrโ selects the SoX Resampler (where available); compensation, and the filter optionsfilter_size,phase_shift,exact_rational,filter_type&kaiser_beta, are not applicable in this case
filter_sizeโ forswronly, set the resampling filter size. Default value is32.phase_shiftโ forswronly, set the resampling phase shift. Default value is10, and it must be in the interval[0,30].linear_interpโ use linear interpolation when enabled (that's the default btw). Disable it if you'd rather preserve speed instead of quality whenexact_rationalfails. Your call bestie โ๏ธexact_rationalโ forswronly. When enabled, it tries to use an exactphase_countbased on the input and output sample rate. But if that ends up larger than1 << phase_shift, then thephase_countfalls back to1 << phase_shift. Default is enabled.cutoffโ set the cutoff frequency ratio (swr: 6dB point;soxr: 0dB point). Must be a float value between0and1. Default value is0.97withswr, and0.91withsoxr(which, with a sample-rate of44100, preserves the entire audio band to 20kHz โ obsessed ๐).precisionโ forsoxronly, the precision in bits to which the resampled signal gets calculated. The default value of20(which, with suitable dithering, is appropriate for a destination bit-depth of16) gives SoX's 'High Quality'. A value of28gives SoX's 'Very High Quality' ๐chebyโ forsoxronly, selects passband rolloff none (Chebyshev) & higher-precision approximation for 'irrational' ratios. Default value is0.asyncโ forswronly, a simple 1-parameter audio sync to timestamps using stretching, squeezing, filling and trimming. Setting this to1enables filling and trimming, and larger values represent the maximum amount in samples that the data may be stretched or squeezed for each second. Default value is0, so no compensation is applied to make the samples match the audio timestamps.first_ptsโ forswronly, assume the first pts should be this value. The time unit is1 / sample rate. This allows for padding/trimming at the start of the stream. By default no assumption is made about the first frame's expected pts, so no padding or trimming happens. Example: you could set this to0to pad the beginning with silence if an audio stream starts after the video stream, or to trim any samples with a negative pts caused by encoder delay. genuinely such a useful little guy ๐ฅบmin_compโ forswronly, set the minimum difference between timestamps and audio data (in seconds) needed to trigger stretching/squeezing/filling or trimming of the data to match the timestamps. The default is that stretching/squeezing/filling and trimming is disabled (min_comp=FLT_MAX). So yeah, off by default.min_hard_compโ forswronly, set the minimum difference between timestamps and audio data (in seconds) to trigger adding/dropping samples to make it match the timestamps. This option is basically a threshold choosing between hard (trim/fill) and soft (squeeze/stretch) compensation. Note that all compensation is disabled by default throughmin_comp. The default here is0.1.comp_durationโ forswronly, set the duration (in seconds) over which data gets stretched/squeezed to match the timestamps. Must be a non-negative double float value. Default value is1.0.max_soft_compโ forswronly, set the maximum factor by which data is stretched/squeezed to match the timestamps. Must be a non-negative double float value. Default value is0.matrix_encodingโ select the matrixed stereo encoding. It accepts the following values:noneโ select nonedolbyโ select Dolbydpliiโ select Dolby Pro Logic II Default value isnone.
filter_typeโ forswronly, select the resampling filter type. This only affects resampling operations. It accepts the following values:cubicโ select cubicblackman_nuttallโ select Blackman Nuttall windowed sinckaiserโ select Kaiser windowed sinc
kaiser_betaโ forswronly, set the Kaiser window beta value. Must be a double float value in the interval[2,16]. Default value is9.output_sample_bitsโ forswronly, set the number of used output sample bits for dithering. Must be an integer in the interval[0,64]. Default value is0, which means it's not used ๐ฆ
โจ SCALER OPTIONS โจ
okay so the video scaler has its own little collection of named options and bestie, they're lowkey important ๐
You can set these by passing -option value in the FFmpeg tools โ with a few lil exceptions that are API-only (I'll flag those, don't worry ๐). And if you're doing that programmatic thing, you can set them explicitly in the SwsContext options or through the libavutil/opt.h API. iykyk ๐ซถ
๐ธ sws_flags
Set the scaler flags, periodt. This is also what you use to pick the scaling algorithm โ and ngl, only a single algorithm should be selected at a time. Default value is bicubic ๐
It accepts the following values:
fast_bilinearโ selects the fast bilinear scaling algorithm โกbilinearโ selects the bilinear scaling algorithmbicubicโ selects the bicubic scaling algorithm (the default, main character energy ๐)experimentalโ selects the experimental scaling algorithm ๐งชneighborโ selects nearest neighbor rescaling algorithmareaโ selects averaging area rescaling algorithmbicublinโ selects bicubic scaling for the luma component, bilinear for the chroma components ๐gaussโ selects Gaussian rescaling algorithmsincโ selects sinc rescaling algorithmlanczosโ selects Lanczos rescaling algorithm. The default width (alpha) is3and can be changed by settingparam0๐splineโ selects natural bicubic spline rescaling algorithmprint_infoโ enable printing/debug logging ๐จ๏ธaccurate_rndโ enable accurate roundingfull_chroma_intโ enable full chroma interpolationfull_chroma_inpโ select full chroma inputbitexactโ enable bitexact outputunstableโ allow the use of experimental new code. May subtly affect the output or even produce wrong results. For testing only ๐จ
bestie pls note: unstable is literally right there in the name โ testing only, no cap ๐
๐ srcw (API only)
Set source width.
๐ srch (API only)
Set source height.
๐ dstw (API only)
Set destination width.
๐ dsth (API only)
Set destination height.
๐ src_format (API only)
Set source pixel format (must be expressed as an integer ๐ข).
๐ dst_format (API only)
Set destination pixel format (must be expressed as an integer ๐ข).
๐ฆ src_range (boolean)
If value is set to 1, it indicates source is full range. Default value is 0, which indicates source is limited range.
๐ฆ dst_range (boolean)
If value is set to 1, enable full range for destination. Default value is 0, which enables limited range.
๐ฆ gamma (boolean)
If value is set to 1, enable gamma correct scaling. Default value is 0.
๐ param0, param1
Set scaling algorithm parameters. The specified values are specific of some scaling algorithms and ignored by others โ so like, some algorithms care, some literally don't ๐ The specified values are floating point number values.
โญ sws_dither
Set the dithering algorithm. Accepts one of the following values. Default value is auto.
autoโ automatic choice ๐ชnoneโ no ditheringbayerโ bayer ditheredโ error diffusion dithera_ditherโ arithmetic dither, based using additionx_ditherโ arithmetic dither, based using xor (more random/less apparent patterning thata_dither) ๐
๐ธ alphablend
Set the alpha blending to use when the input has alpha but the output does not. Default value is none.
uniform_colorโ blend onto a uniform background colorcheckerboardโ blend onto a checkerboard ๐noneโ no blending
๐ฌ FILTERING INTRODUCTION ๐ฌ
Filtering in FFmpeg is enabled through the libavfilter library. slay ๐
In libavfilter, a filter can have multiple inputs and multiple outputs. To illustrate the sorts of things that are possible, we consider the following filtergraph:
[main]
input --> split ---------------------> overlay --> output
| ^
|[tmp] [flip]|
+-----> crop --> vflip -------+
This filtergraph splits the input stream in two streams, then sends one stream through the crop filter and the vflip filter, before merging it back with the other stream by overlaying it on top. You can use the following command to achieve this:
ffmpeg -i INPUT -vf "split [main][tmp]; [tmp] crop=iw:ih/2:0:0, vflip [flip]; [main][flip] overlay=0:H/2" OUTPUT
The result will be that the top half of the video is mirrored onto the bottom half of the output video. iconic behavior honestly ๐ชโจ
Filters in the same linear chain are separated by commas, and distinct linear chains of filters are separated by semicolons. In our example, crop,vflip are in one linear chain, split and overlay are separately in another. The points where the linear chains join are labelled by names enclosed in square brackets โ in the example, the split filter generates two outputs that are associated to the labels [main] and [tmp] ๐
The stream sent to the second output of split, labelled as [tmp], is processed through the crop filter, which crops away the lower half part of the video, and then vertically flipped. The overlay filter takes in input the first unchanged output of the split filter (which was labelled as [main]), and overlay on its lower half the output generated by the crop,vflip filterchain.
Some filters take in input a list of parameters: they are specified after the filter name and an equal sign, and are separated from each other by a colon ๐ซถ
There exist so-called source filters that do not have an audio/video input, and sink filters that will not have audio/video output.
๐ GRAPH ๐
The graph2dot program included in the FFmpeg tools directory can be used to parse a filtergraph description and issue a corresponding textual representation in the dot language.
Invoke the command:
graph2dot -h
to see how to use graph2dot.
You can then pass the dot description to the dot program (from the graphviz suite of programs) and obtain a graphical representation of the filtergraph ๐ผ๏ธโจ
For example the sequence of commands:
echo <GRAPH_DESCRIPTION> | \
tools/graph2dot -o graph.tmp && \
dot -Tpng graph.tmp -o graph.png && \
display graph.png
can be used to create and display an image representing the graph described by the GRAPH_DESCRIPTION string. Note that this string must be a complete self-contained graph, with its inputs and outputs explicitly defined. For example if your command line is of the form:
ffmpeg -i infile -vf scale=640:360 outfile
your GRAPH_DESCRIPTION string will need to be of the form:
nullsrc,scale=640:360,nullsink
you may also need to set the nullsrc parameters and add a format filter in order to simulate a specific input file ๐ง
๐ FILTERGRAPH DESCRIPTION โจ
okay bestie, picture this: a filtergraph is literally a directed graph of connected filters, no cap. it can contain cycles (yes, cycles, it's giving chaos but make it legal), and there can be multiple links between a pair of filters. every single link has one input pad on one side โ connecting it to one filter from which it takes its input โ and one output pad on the other side, connecting it to one filter accepting its output. that's the whole anatomy, periodt.
each filter in a filtergraph is an instance of a filter class registered in the application, and that class is what defines the features and the number of input and output pads the filter gets. it's the blueprint, the filter is the fit.
a filter with no input pads is called a "source", and a filter with no output pads is called a "sink". main character energy vs. exit-the-chat energy, honestly.
โจ Filtergraph syntax โจ
a filtergraph has a textual representation, and it's recognized by the -filter/-vf/-af and -filter_complex options in ffmpeg, and by -vf/-af in ffplay, and also by the avfilter_graph_parse_ptr() function defined in libavfilter/avfilter.h. so yeah, it gets around ๐ฆ
a filterchain consists of a sequence of connected filters, each one connected to the previous one in the sequence. a filterchain is represented by a list of ,-separated filter descriptions.
a filtergraph consists of a sequence of filterchains. a sequence of filterchains is represented by a list of ;-separated filterchain descriptions.
a filter is represented by a string of the form:
[in_link_1]...[in_link_N]filter_name@id=arguments[out_link_1]...[out_link_M]
filter_name is the name of the filter class of which the described filter is an instance of, and it has to be the name of one of the filter classes registered in the program โ optionally followed by @id. and the name of the filter class is optionally followed by the string =arguments.
arguments is a string containing the parameters used to initialize the filter instance. it can take one of two forms:
- a
:-separated list ofkey=valuepairs. - a
:-separated list of value. in this case the keys are assumed to be the option names in the order they are declared. e.g. thefadefilter declares three options in this order โtype,start_frameandnb_frames. so then the parameter listin:0:30means the valueinis assigned to the optiontype,0tostart_frameand30tonb_frames. iykyk ๐ - a
:-separated list of mixed direct value and longkey=valuepairs. the direct value must precede thekey=valuepairs, and follow the same constraints order of the previous point. the followingkey=valuepairs can be set in any preferred order. slay, flexible.
if the option value itself is a list of items (e.g. the format filter takes a list of pixel formats), the items in the list are usually separated by |.
the list of arguments can be quoted using the character ' as initial and ending mark, and the character \ for escaping the characters within the quoted text. otherwise the argument string is considered terminated when the next special character (belonging to the set []=;,) is encountered. ๐
a special syntax implemented in the ffmpeg CLI tool allows loading option values from files. this is done by prepending a slash / to the option name, then the supplied value is interpreted as a path from which the actual value is loaded. e.g.
ffmpeg -i <INPUT> -vf drawtext=/text=/tmp/some_text <OUTPUT>
will load the text to be drawn from /tmp/some_text. API users wishing to implement a similar feature should use the avfilter_graph_segment_*() functions together with custom IO code. fancy!
the name and arguments of the filter are optionally preceded and followed by a list of link labels. a link label lets you name a link and associate it to a filter output or input pad. the preceding labels in_link_1 ... in_link_N are associated to the filter input pads, the following labels out_link_1 ... out_link_M are associated to the output pads.
when two link labels with the same name are found in the filtergraph, a link between the corresponding input and output pad is created. match made in heaven ๐
if an output pad is not labelled, it is linked by default to the first unlabelled input pad of the next filter in the filterchain. for example in the filterchain
nullsrc, split[L1], [L2]overlay, nullsink
the split filter instance has two output pads, and the overlay filter instance two input pads. the first output pad of split is labelled "L1", the first input pad of overlay is labelled "L2", and the second output pad of split is linked to the second input pad of overlay, which are both unlabelled. see how that works? unlabelled ones just find each other ๐ซถ
in a filter description, if the input label of the first filter is not specified, in is assumed; if the output label of the last filter is not specified, out is assumed.
in a complete filterchain all the unlabelled filter input and output pads must be connected. a filtergraph is considered valid if all the filter input and output pads of all the filterchains are connected. no floating pads, no exceptions, bestie โ that's the vibe check.
leading and trailing whitespaces (space, tabs, or line feeds) separating tokens in the filtergraph specification are ignored. which means you can express the filtergraph using empty lines and spaces to improve readability. aesthetic AND functional, we love to see it ๐ธ
for example, the filtergraph:
testsrc,split[L1],hflip[L2];[L1][L2] hstack
can be represented as:
testsrc,
split [L1], hflip [L2];
[L1][L2] hstack
Libavfilter will automatically insert scale filters where format conversion is required. and it's possible to specify swscale flags for those automatically inserted scalers by prepending sws_flags=flags; to the filtergraph description. auto-scaling, but make it your call.
here is a BNF description of the filtergraph syntax:
<NAME> ::= sequence of alphanumeric characters and '_'
<FILTER_NAME> ::= <NAME>["@"<NAME>]
<LINKLABEL> ::= "[" <NAME> "]"
<LINKLABELS> ::= <LINKLABEL> [<LINKLABELS>]
<FILTER_ARGUMENTS> ::= sequence of chars (possibly quoted)
<FILTER> ::= [<LINKLABELS>] <FILTER_NAME> ["=" <FILTER_ARGUMENTS>] [<LINKLABELS>]
<FILTERCHAIN> ::= <FILTER> [,<FILTERCHAIN>]
<FILTERGRAPH> ::= [sws_flags=<flags>;] <FILTERCHAIN> [;<FILTERGRAPH>]
๐ Notes on filtergraph escaping ๐
ok this is the part where it gets spicy ๐ญ filtergraph description composition entails several levels of escaping. see the "Quoting and escaping" section in the ffmpeg-utils(1) manual for more information about the employed escaping procedure.
- a first level escaping affects the content of each filter option value, which may contain the special character
:used to separate values, or one of the escaping characters\'. - a second level escaping affects the whole filter description, which may contain the escaping characters
\'or the special characters[],;used by the filtergraph description. - finally, when you specify a filtergraph on a shell commandline, you need to perform a third level escaping for the shell special characters contained within it.
for example, consider the following string to be embedded in the drawtext filter description text value:
this is a 'string': may contain one, or more, special characters
this string contains the ' special escaping character, and the : special character, so it needs to be escaped in this way:
text=this is a \'string\'\: may contain one, or more, special characters
a second level of escaping is required when embedding the filter description in a filtergraph description, in order to escape all the filtergraph special characters. thus the example above becomes:
drawtext=text=this is a \\\'string\\\'\\: may contain one\, or more\, special characters
(note that in addition to the \' escaping special characters, also , needs to be escaped). yeah. look at all those backslashes. it's giving ancient runes ๐
finally an additional level of escaping is needed when writing the filtergraph description in a shell command, which depends on the escaping rules of the adopted shell. for example, assuming that \ is special and needs to be escaped with another \, the previous string will finally result in:
-vf "drawtext=text=this is a \\\\\\'string\\\\\\'\\\\: may contain one\\, or more\\, special characters"
in order to avoid cumbersome escaping when using a commandline tool accepting a filter specification as input, it is advisable to avoid direct inclusion of the filter or options specification in the shell.
for example, in case of the drawtext filter, you might prefer to use the textfile option in place of text to specify the text to render. seriously bestie, save yourself the emotional damage ๐ซถ
โฐ TIMELINE EDITING โฐ
some filters support a generic enable option. for the filters supporting timeline editing, this option can be set to an expression which is evaluated before sending a frame to the filter. if the evaluation is non-zero, the filter will be enabled; otherwise the frame will be sent unchanged to the next filter in the filtergraph. like, the filter just steps aside, respectfully.
the expression accepts the following values:
tโ timestamp expressed in seconds,NANif the input timestamp is unknownnโ sequential number of the input frame, starting from0posโ the position in the file of the input frame,NANif unknown; deprecated, do not use โ ๏ธ like fr fr, don'tw,hโ width and height of the input frame if video
additionally, these filters support an enable command that can be used to re-define the expression.
like any other filtering option, the enable option follows the same rules.
for example, to enable a blur filter (smartblur) from 10 seconds to 3 minutes, and a curves filter starting at 3 seconds:
smartblur = enable='between(t,10,3*60)',
curves = enable='gte(t,3)' : preset=cross_process
see ffmpeg -filters to view which filters have timeline support. go check, it's free ๐
๐ฎ CHANGING OPTIONS AT RUNTIME WITH A COMMAND ๐ฎ
some options can be changed during the operation of the filter using a command. these options are marked T on the output of ffmpeg -h filter=<name of filter>. the name of the command is the name of the option, and the argument is the new value. live tweaking, no restart needed ๐
โจ OPTIONS FOR FILTERS WITH SEVERAL INPUTS โจ
okay so some filters have several inputs and they all share a lil common set of options ๐ซถ and here's the tea: you can only set these by name โ the short notation simply does not work for them, no cap ๐
eof_actionโ what to do when EOF hits the secondary input. it takes one of these values:repeatโ repeat the last frame. this is the default, she's the safe queen ๐endallโ end both streams, everybody goes home ๐passโ pass the main input through
shortestโ set to1and the output is forced to terminate when the shortest input terminates. default is0repeatlastโ set to1and the filter is forced to extend the last frame of the secondary streams alllll the way to the end of the primary stream ๐ง a value of0disables this behavior. default is1ts_sync_modeโ how strictly to sync streams based on secondary input timestamps. the values are:defaultโ frame from secondary input with the nearest lower or equal timestamp to the primary input framenearestโ frame from secondary input with the absolute nearest timestamp to the primary input frame
๐ธ AUDIO FILTERS ๐ธ
when you configure your FFmpeg build you can disable any of the existing filters with --disable-filters โจ and the configure output will show you the audio filters that made it into your build, so you know exactly who's invited to the party ๐
below is a description of the currently available audio filters. buckle up bestie, it's a long list ๐
๐ฆ aap
apply Affine Projection algorithm to the first audio stream using the second audio stream โจ
this adaptive filter is used to estimate unknown audio based on multiple input audio samples. the Affine projection algorithm can make trade-offs between computation complexity and convergence speed โ it's literally giving balance ๐
here's the description of the accepted options:
orderโ set the filter orderprojectionโ set the projection ordermuโ set the filter mudeltaโ set the coefficient to initialize the internal covariance matrixout_modeโ set the filter output samples. it accepts these values:iโ pass the 1st inputdโ pass the 2nd inputoโ pass difference between desired, 2nd input and error signal estimatenโ pass difference between input, 1st input and error signal estimateeโ pass error signal estimated samples
default value is o
precisionโ set which precision to use when processing samples:autoโ auto pick internal sample format depending on other filtersfloatโ always use single-floating point precision sample formatdoubleโ always use double-floating point precision sample format
๐ acompressor
a compressor is mainly used to reduce the dynamic range of a signal. especially modern music is mostly compressed at a high ratio to improve the overall loudness ๐ฅ it's done to get the highest attention of a listener, "fatten" the sound and bring more "power" to the track. if a signal is compressed too much it may sound dull or "dead" afterwards or it may start to "pump" (which could be a powerful effect but can also destroy a track completely ๐ญ). the right compression is the key to reach a professional sound and is the high art of mixing and mastering. because of its complex settings it may take a long time to get the right feeling for this kind of effect โ lowkey it's a whole journey ๐ง
compression is done by detecting the volume above a chosen level "threshold" and dividing it by the factor set with "ratio" โจ so if you set the threshold to -12dB and your signal reaches -6dB a ratio of 2:1 will result in a signal at -9dB. because an exact manipulation of the signal would cause distortion of the waveform the reduction can be levelled over the time. this is done by setting "Attack" and "Release". "attack" determines how long the signal has to rise above the threshold before any reduction will occur and "release" sets the time the signal has to fall below the threshold to reduce the reduction again. shorter signals than the chosen attack time will be left untouched ๐
the overall reduction of the signal can be made up afterwards with the "makeup" setting. so compressing the peaks of a signal about 6dB and raising the makeup to this level results in a signal twice as loud as the source ๐ to gain a softer entry in the compression the "knee" flattens the hard edge at the threshold in the range of the chosen decibels.
the filter accepts these options:
level_inโ set input gain. default is1. range is between0.015625and64modeโ set mode of compressor operation. can beupwardordownward. default isdownwardthresholdโ if a signal of stream rises above this level it will affect the gain reduction. by default it is0.125. range is between0.00097563and1ratioโ set a ratio by which the signal is reduced.1:2means that if the level rose4dBabove the threshold, it will be only2dBabove after the reduction. default is2. range is between1and20attackโ amount of milliseconds the signal has to rise above the threshold before gain reduction starts. default is20. range is between0.01and2000releaseโ amount of milliseconds the signal has to fall below the threshold before reduction is decreased again. default is250. range is between0.01and9000makeupโ set the amount by how much signal will be amplified after processing. default is1. range is from1to64kneeโ curve the sharp knee around the threshold to enter gain reduction more softly. default is2.82843. range is between1and8linkโ choose if the "average" level between all channels of input stream or the louder ("maximum") channel of input stream affects the reduction. default isaveragedetectionโ should the exact signal be taken in case ofpeakor an RMS one in case ofrms. default isrmswhich is mostly smoother โจmixโ how much to use compressed signal in output. default is1. range is between0and1
Commands
this filter supports all the above options as commands, periodt ๐
๐ acontrast
simple audio dynamic range compression/expansion filter.
the filter accepts these options:
contrastโ set contrast. default is33. allowed range is between0and100
โญ acopy
copy the input audio source unchanged to the output. this is mainly useful for testing purposes, she's literally just standing there being a vibe check ๐ซถ
๐ acrossfade
apply cross fade from one input audio stream to another input audio stream โจ the cross fade is applied for the specified duration near the end of the first stream.
the filter accepts these options:
inputs,nโ specify the number of inputs to crossfade. when crossfading multiple inputs, each input will be concatenated and crossfaded in sequence, similar to the concat filter. default is2nb_samples,nsโ specify the number of samples for which the cross fade effect has to last. at the end of the cross fade effect the first input audio will be completely silent. default is44100duration,dโ specify the duration of the cross fade effect. see the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. by default the duration is determined bynb_samples. if set, this option is used instead ofnb_samplesoverlap,oโ should first stream end overlap with second stream start. default is enabledcurve1โ set curve for cross fade transition for first streamcurve2โ set curve for cross fade transition for second stream
for description of available curve types see the afade filter description ๐
Examples
- cross fade from one input to another:
ffmpeg -i first.flac -i second.flac -filter_complex acrossfade=d=10:c1=exp:c2=exp output.flac
- cross fade from one input to another but without overlapping:
ffmpeg -i first.flac -i second.flac -filter_complex acrossfade=d=10:o=0:c1=exp:c2=exp output.flac
- concatenate multiple inputs with cross fade between each:
ffmpeg -i first.flac -i second.flac -i third.flac -filter_complex acrossfade=n=3 output.flac
๐ง acrossover
split audio stream into several bands ๐ถ
this filter splits audio stream into two or more frequency ranges. summing all streams back will give flat output โ icon behavior, honestly ๐
the filter accepts these options:
splitโ set split frequencies. those must be positive and increasingorderโ set filter order for each band split. this controls filter roll-off or steepness of filter transfer function. available values are:2ndโ 12 dB per octave4thโ 24 dB per octave6thโ 36 dB per octave8thโ 48 dB per octave10thโ 60 dB per octave12thโ 72 dB per octave14thโ 84 dB per octave16thโ 96 dB per octave18thโ 108 dB per octave20thโ 120 dB per octave
default is 4th
levelโ set input gain level. allowed range is from0to1. default value is1gainsโ set output gain for each band. default value is1for all bandsprecisionโ set which precision to use when processing samples:autoโ auto pick internal sample format depending on other filtersfloatโ always use single-floating point precision sample formatdoubleโ always use double-floating point precision sample format
default value is auto
Examples
- split input audio stream into two bands (low and high) with split frequency of
1500 Hz, each band will be in a separate stream:
ffmpeg -i in.flac -filter_complex 'acrossover=split=1500[LOW][HIGH]' -map '[LOW]' low.wav -map '[HIGH]' high.wav
- same as above, but with higher filter order:
ffmpeg -i in.flac -filter_complex 'acrossover=split=1500:order=8th[LOW][HIGH]' -map '[LOW]' low.wav -map '[HIGH]' high.wav
- same as above, but also with an additional middle band (frequencies between
1500and8000):
ffmpeg -i in.flac -filter_complex 'acrossover=split=1500 8000:order=8th[LOW][MID][HIGH]' -map '[LOW]' low.wav -map '[MID]' mid.wav -map '[HIGH]' high.wav
๐ acrusher
reduce audio bit resolution.
okay so this filter is literally a bit crusher with enhanced functionality, and she is serving ๐ A bit crusher is used to audibly reduce the number of bits an audio signal is sampled with. It does not change the bit depth at all โ it just produces the effect. Material reduced in bit depth sounds more harsh and "digital". This filter can even round to continuous values instead of discrete bit depths. It also has a D/C offset which results in different crushing of the lower and the upper half of the signal. And there's an Anti-Aliasing setting that can produce "softer" crushing sounds. iconic.
Another feature is the logarithmic mode. This setting switches from linear distances between bits to logarithmic ones. The result is a much more "natural" sounding crusher which doesn't gate low signals, for example. The human ear has a logarithmic perception, so this kind of crushing is much more pleasant. Logarithmic crushing is also able to get anti-aliased. obsessed.
The filter accepts the following options:
level_inโ Set level in.level_outโ Set level out.bitsโ Set bit reduction.mixโ Set mixing amount.modeโ Can be linear:"lin"or logarithmic:"log".dcโ Set DC.aaโ Set anti-aliasing.samplesโ Set sample reduction.lfoโ Enable LFO. By default disabled.lforangeโ Set LFO range.lforateโ Set LFO rate.
Commands
This filter supports all the above options as commands. slay.
๐ acue
Delay audio filtering until a given wallclock timestamp. See the cue filter. no cap.
๐ฆ adeclick
Remove impulsive noise from input audio. Samples detected as impulsive noise are replaced by interpolated samples using autoregressive modelling.
window,wโ Set window size, in milliseconds. Allowed range is from10to100. Default value is55milliseconds. This sets the size of the window which will be processed at once.overlap,oโ Set window overlap, in percentage of window size. Allowed range is from50to95. Default value is75percent. Setting this to a very high value increases impulsive noise removal but makes the whole process much slower.arorder,aโ Set autoregression order, in percentage of window size. Allowed range is from0to25. Default value is2percent. This option also controls quality of interpolated samples using neighbour good samples.threshold,tโ Set threshold value. Allowed range is from1to100. Default value is2. This controls the strength of impulsive noise which is going to be removed. The lower the value, the more samples will be detected as impulsive noise.burst,bโ Set burst fusion, in percentage of window size. Allowed range is0to10. Default value is2. If any two samples detected as noise are spaced less than this value, then any sample between those two samples will also be detected as noise.method,mโ Set overlap method.- It accepts the following values:
add,aโ Select overlap-add method. Even not interpolated samples are slightly changed with this method.save,sโ Select overlap-save method. Not interpolated samples remain unchanged.
- Default value is
"a".
- It accepts the following values:
๐ธ adeclip
Remove clipped samples from input audio. Samples detected as clipped are replaced by interpolated samples using autoregressive modelling.
window,wโ Set window size, in milliseconds. Allowed range is from10to100. Default value is55milliseconds. This sets the size of the window which will be processed at once.overlap,oโ Set window overlap, in percentage of window size. Allowed range is from50to95. Default value is75percent.arorder,aโ Set autoregression order, in percentage of window size. Allowed range is from0to25. Default value is8percent. This option also controls quality of interpolated samples using neighbour good samples.threshold,tโ Set threshold value. Allowed range is from1to100. Default value is10. Higher values make clip detection less aggressive.hsize,nโ Set size of histogram used to detect clips. Allowed range is from100to9999. Default value is1000. Higher values make clip detection less aggressive.method,mโ Set overlap method.- It accepts the following values:
add,aโ Select overlap-add method. Even not interpolated samples are slightly changed with this method.save,sโ Select overlap-save method. Not interpolated samples remain unchanged.
- Default value is
"a".
- It accepts the following values:
๐ adecorrelate
Apply decorrelation to input audio stream.
The filter accepts the following options:
stagesโ Set decorrelation stages of filtering. Allowed range is from1to16. Default value is6.seedโ Set random seed used for setting delay in samples across channels.
โจ adelay
Delay one or more audio channels. Samples in delayed channel are filled with silence.
The filter accepts the following option:
delaysโ Set list of delays in milliseconds for each channel separated by'|'. Unused delays will be silently ignored. If the number of given delays is smaller than the number of channels, all remaining channels will not be delayed. If you want to delay an exact number of samples, append'S'to the number. If you want instead to delay in seconds, append's'to the number.allโ Use last set delay for all remaining channels. By default is disabled. This option if enabled changes how option"delays"is interpreted.
Examples
- Delay first channel by
1.5seconds, the third channel by0.5seconds and leave the second channel (and any other channels that may be present) unchanged.
adelay=1500|0|500
- Delay second channel by
500samples, the third channel by700samples and leave the first channel (and any other channels that may be present) unchanged.
adelay=0|500S|700S
- Delay all channels by same number of samples:
adelay=delays=64S:all=1
๐ adenorm
Remedy denormals in audio by adding extremely low-level noise. This filter shall be placed before any filter that can produce denormals.
A description of the accepted parameters follows.
levelโ Set level of added noise in dB. Default is-351. Allowed range is from-451to-90.typeโ Set type of added noise.dcโ Add DC signal.acโ Add AC signal.squareโ Add square signal.pulseโ Add pulse signal.- Default is
"dc".
Commands
This filter supports all the above options as commands. ๐
๐ง aderivative, aintegral
Compute derivative/integral of audio stream.
Applying both filters one after another produces original audio. literally math but make it audio.
๐ฅ adrc
Apply spectral dynamic range controller filter to input audio stream.
A description of the accepted options follows.
transferโ Set the transfer expression.- The expression can contain the following constants:
chโ current channel numbersnโ current sample numbernb_channelsโ number of channelstโ timestamp expressed in secondssrโ sample ratepโ current frequency power value, in dBfโ current frequency in Hz
- Default value is
"p".
- The expression can contain the following constants:
attackโ Set the attack in milliseconds. Default is50milliseconds. Allowed range is from1to1000milliseconds.releaseโ Set the release in milliseconds. Default is100milliseconds. Allowed range is from5to2000milliseconds.channelsโ Set which channels to filter, by default"all"channels in audio stream are filtered.
Commands
This filter supports all the above options as commands. periodt.
Examples
- Apply spectral compression to all frequencies with threshold of
-50dB and1:6ratio:
adrc=transfer='if(gt(p,-50),-50+(p-(-50))/6,p)':attack=50:release=100
- Similar to above but with
1:2ratio and filtering only front center channel:
adrc=transfer='if(gt(p,-50),-50+(p-(-50))/2,p)':attack=50:release=100:channels=FC
- Apply spectral noise gate to all frequencies with threshold of
-85dB and with short attack time and short release time:
adrc=transfer='if(lte(p,-85),p-800,p)':attack=1:release=5
- Apply spectral expansion to all frequencies with threshold of
-10dB and1:2ratio:
adrc=transfer='if(lt(p,-10),-10+(p-(-10))*2,p)':attack=50:release=100
- Apply limiter to max
-60dB to all frequencies, with attack of2ms and release of10ms:
adrc=transfer='min(p,-60)':attack=2:release=10
๐ adynamicequalizer
Apply dynamic equalization to input audio stream.
A description of the accepted options follows.
thresholdโ Set the detection threshold used to trigger equalization. Threshold detection is using detection filter. Default value is0. Allowed range is from0to100.dfrequencyโ Set the detection frequency in Hz used for detection filter used to trigger equalization. Default value is1000Hz. Allowed range is between2and1000000Hz.dqfactorโ Set the detection resonance factor for detection filter used to trigger equalization. Default value is1. Allowed range is from0.001to1000.tfrequencyโ Set the target frequency of equalization filter. Default value is1000Hz. Allowed range is between2and1000000Hz.tqfactorโ Set the target resonance factor for target equalization filter. Default value is1. Allowed range is from0.001to1000.attackโ Set the amount of milliseconds the signal from detection has to rise above the detection threshold before equalization starts. Default is20. Allowed range is between1and2000.releaseโ Set the amount of milliseconds the signal from detection has to fall below the detection threshold before equalization ends. Default is200. Allowed range is between1and2000.ratioโ Set the ratio by which the equalization gain is raised. Default is1. Allowed range is between0and30.makeupโ Set the makeup offset by which the equalization gain is raised. Default is0. Allowed range is between0and100.rangeโ Set the max allowed cut/boost amount. Default is50. Allowed range is from1to200.modeโ Set the mode of filter operation, can be one of the following:listenโ Output only isolated detection signal.
cutbelowโ cuts the frequencies below the detection threshold. gone, โ๏ธ bye.cutaboveโ cuts the frequencies above the detection threshold.boostbelowโ boosts the frequencies below the detection threshold instead of cutting them ๐ฅboostaboveโ boosts the frequencies above the detection threshold.
Default mode is cutbelow, bestie. That's the starting vibe.
dftypeโ sets the type of detection filter. pick your fighter, one of these:bandpasslowpasshighpasspeak
Default type is bandpass.
tftypeโ sets the type of target filter. the options are giving very specific energy:belllowshelfhighshelf
Default type is bell.
autoโ automatically grabs the threshold from the detection filter. by default it's disabled. this one is lowkey iconic when you want to detect the threshold inside a certain time frame of the input audio stream โ in that case the option value literally changes at runtime, no cap. the available values are:disabledโ disables using the automatically gathered threshold value.offโ stop picking the threshold value.onโ start picking the threshold value.adaptiveโ adaptively picks the threshold value by calculating sliding window entropy. big brain moment ๐ง โจ
precisionโ sets which precision to use when processing samples:autoโ auto picks the internal sample format depending on other filters.floatโ always uses the single-floating point precision sample format.doubleโ always uses the double-floating point precision sample format.
Commands
This filter supports all the above options as commands. yes, all of them. live tweaking, slay ๐
๐ฆ adynamicsmooth ๐ฆ
Applies dynamic smoothing to the input audio stream. it's giving glow-up but for your waveform โจ
Here's what the accepted options are about:
sensitivityโ sets how sensitive it is to frequency fluctations. default is2. allowed range is from0to1e+06.basefreqโ sets a base frequency for the smoothing. default value is22050. allowed range is from2to1e+06.
Commands
This filter supports all the above options as commands ๐
๐ aecho ๐
Applies echoing to the input audio. we're literally in a cave now, bestie ๐๏ธ
So โ echoes are reflected sound. they can happen naturally amongst mountains (and sometimes large buildings) when you talk or shout, and digital echo effects emulate that whole behaviour. people use them constantly to help fill out the sound of a single instrument or vocal, it's a classic. The time difference between the original signal and the reflection is the "delay", and the loudness of the reflected signal is the "decay". Multiple echoes can each have their own different delays and decays. obsessed.
Here are the accepted parameters:
in_gainโ sets the input gain of the reflected signal. default is0.6.out_gainโ sets the output gain of the reflected signal. default is0.3.delaysโ sets the list of time intervals in milliseconds between the original signal and the reflections, separated by'|'. allowed range for each"delay"is(0 - 90000.0]. default is1000.decaysโ sets the list of loudness of the reflected signals, separated by'|'. allowed range for each"decay"is(0 - 1.0]. default is0.5.
Examples
- Make it sound as if there are twice as many instruments as are actually playing:
aecho=0.8:0.88:60:0.4
- If the delay is very short, then it sounds like a (metallic) robot playing music ๐ค๐ถ:
aecho=0.8:0.88:6:0.4
- A longer delay will sound like an open air concert in the mountains:
aecho=0.8:0.9:1000:0.3
- Same as above but with one more mountain โฐ๏ธโฐ๏ธ:
aecho=0.8:0.9:1000|1800:0.3|0.25
๐ aemphasis ๐
The audio emphasis filter creates or restores material that was taken directly from LPs or emphased CDs with different filter curves. like, to store music on vinyl the signal has to be altered by a filter first to even out the disadvantages of that recording medium. then once the material is played back, the inverse filter has to be applied to restore the distortion of the frequency response. it's a whole cycle, fr fr ๐ฟ
The filter accepts the following options:
level_inโ sets the input gain.level_outโ sets the output gain.modeโ sets the filter mode. for restoring material use"reproduction"mode, otherwise use"production"mode. default is"reproduction"mode.typeโ sets the filter type. this selects the medium. can be one of the following:colโ select Columbia.emiโ select EMI.bsiโ select BSI (78RPM).riaaโ select RIAA.cdโ select Compact Disc (CD).50fmโ select 50ยตs (FM).75fmโ select 75ยตs (FM).50kfโ select 50ยตs (FM-KF).75kfโ select 75ยตs (FM-KF).
Commands
This filter supports all the above options as commands ๐ซถ
โญ aeval โญ
Modifies an audio signal according to the specified expressions. math but make it audio ๐งฎโจ
This filter accepts one or more expressions (one for each channel), which get evaluated and used to modify a corresponding audio signal.
It accepts the following parameters:
exprsโ sets the'|'-separated expressions list for each separate channel. If the number of input channels is greater than the number of expressions, the last specified expression is used for the remaining output channels. so the last one is the main character for everyone left over ๐channel_layout,cโ sets the output channel layout. If not specified, the channel layout is specified by the number of expressions. If set tosame, it will use by default the same input channel layout.
Each expression in exprs can contain the following constants and functions:
chโ channel number of the current expression.nโ number of the evaluated sample, starting from0.sโ sample rate.tโ time of the evaluated sample expressed in seconds.nb_in_channels,nb_out_channelsโ input and output number of channels.val(CH)โ the value of the input channel with number CH.
Note: this filter is slow. For faster processing you should use a dedicated filter. we respect honesty here ๐
Examples
- Half volume:
aeval=val(ch)/2:c=same
- Invert phase of the second channel:
aeval=val(0)|-val(1)
๐ฅ aexciter ๐ฅ
An exciter is used to produce high sound that is not present in the original signal. this is done by creating harmonic distortions of the signal which are restricted in range and then added to the original signal. An Exciter raises the upper end of an audio signal without simply raising the higher frequencies like an equalizer would do โ the whole point is to create a more "crisp" or "brilliant" sound. it's giving โจsparkleโจ
The filter accepts the following options:
level_inโ sets the input level prior to processing of the signal. allowed range is from0to64. default value is1.level_outโ sets the output level after processing of the signal. allowed range is from0to64. default value is1.amountโ sets the amount of harmonics added to the original signal. allowed range is from0to64. default value is1.driveโ sets the amount of newly created harmonics. allowed range is from0.1to10. default value is8.5.blendโ sets the octave of the newly created harmonics. allowed range is from-10to10. default value is0.freqโ sets the lower frequency limit of producing harmonics, in Hz. allowed range is from2000to12000Hz. default is7500Hz.ceilโ sets the upper frequency limit of producing harmonics. allowed range is from9999to20000Hz. If the value is lower than10000Hz, no limit is applied.listenโ mutes the original signal and outputs only the added harmonics. by default it's disabled. solo mode, basically ๐
Commands
This filter supports all the above options as commands ๐
๐ธ afade ๐ธ
Applies a fade-in/out effect to the input audio. the classic, the icon, the moment ๐ฌ
Here are the accepted parameters:
type,tโ specifies the effect type. either"in"for a fade-in, or"out"for a fade-out effect. default is"in".start_sample,ssโ specifies the number of the start sample for starting to apply the fade effect. default is0.nb_samples,nsโ specifies the number of samples for which the fade effect has to last. At the end of the fade-in effect the output audio will have the same volume as the input audio, and at the end of the fade-out transition the output audio will be silence. default is44100.start_time,stโ specifies the start time of the fade effect. default is0. The value must be specified as a time duration; see the Time duration section in the ffmpeg-utils(1) manual for the accepted syntax. If set, this option is used instead ofstart_sample.duration,dโ specifies the duration of the fade effect. See the Time duration section in the ffmpeg-utils(1) manual for the accepted syntax. At the end of the fade-in effect the output audio will have the same volume as the input audio, and at the end of the fade-out transition the output audio will be silence. By default the duration is determined bynb_samples. If set, this option is used instead ofnb_samples.curveโ sets the curve for the fade transition. prepare yourself, there's a lot of them:triโ select triangular, linear slope (default)qsinโ select quarter of sine wavehsinโ select half of sine waveesinโ select exponential sine wavelogโ select logarithmiciparโ select inverted parabolaquaโ select quadraticcubโ select cubicsquโ select square rootcbrโ select cubic rootparโ select parabolaexpโ select exponentialiqsinโ select inverted quarter of sine waveihsinโ select inverted half of sine wavedeseโ select double-exponential seatdesiโ select double-exponential sigmoidlosiโ select logistic sigmoidsincโ select sine cardinal functionisincโ select inverted sine cardinal functionquatโ select quarticquatrโ select quartic rootqsin2โ select squared quarter of sine wavehsin2โ select squared half of sine wavenofadeโ no fade applied
silenceโ sets the initial gain for fade-in, or the final gain for fade-out. default value is0.0.unityโ sets the initial gain for fade-out, or the final gain for fade-in. default value is1.0.
Commands
This filter supports all the above options as commands โจ
Examples
- Fade in the first 15 seconds of audio:
afade=t=in:ss=0:d=15
- Fade out the last 25 seconds of a 900 seconds audio:
afade=t=out:st=875:d=25
๐ง afftdn ๐ง
Denoise audio samples with FFT. we love a clean-sounding bestie ๐ซง
okay so here's the full rundown of every parameter this thing takes. buckle up ๐
noise_reduction,nrโ sets how much noise reduction you get, in dB. allowed range is0.01to97. default is12dB. โจnoise_floor,nfโ sets the noise floor, in dB. allowed range is-80to-20. default is-50dB.noise_type,ntโ picks what kind of noise we're dealing with. it accepts these values:white,wโ select white noise.vinyl,vโ select vinyl noise.shellac,sโ select shellac noise.custom,cโ select custom noise, defined in thebnoption.
default value is white noise. literally the classic ๐
band_noise,bnโ set a custom band noise profile for every one of 15 bands. bands are separated by' 'or'|'. yep, fifteen, count 'em.residual_floor,rfโ sets the residual floor in dB. allowed range is-80to-20. default is-38dB.track_noise,tnโ turns on noise floor tracking. by default it's disabled. with this enabled, the noise floor gets automatically adjusted. ๐ฆtrack_residual,trโ turns on residual tracking. by default it's disabled.output_mode,omโ sets the output mode. it accepts these values:input,iโ pass input unchanged.output,oโ pass noise filtered out.noise,nโ pass only noise.
default value is output.
adaptivity,adโ sets the adaptivity factor, which is used for how fast to adapt gains adjustments per each frequency bin. value0enables instant adaptation, while higher values react much slower. allowed range is from0to1. default value is0.5.floor_offset,foโ sets the noise floor offset factor. this option is used to adjust offset applied to measured noise floor. it's only effective when noise floor tracking is enabled. allowed range is from-2.0to2.0. default value is1.0.noise_link,nlโ sets the noise link used for multichannel audio. it accepts these values:noneโ use unchanged channel's noise floor.minโ use measured min noise floor of all channels.maxโ use measured max noise floor of all channels.averageโ use measured average noise floor of all channels.
default value is min.
band_multiplier,bmโ sets the band multiplier factor, used for how much to spread bands across frequency bins. allowed range is from0.2to5. default value is1.25.sample_noise,snโ toggles capturing and measurement of the noise profile from the input audio. it accepts these values:start,beginโ start sample noise capture.stop,endโ stop sample noise capture and measure new noise band profile.
default value is "none".
gain_smooth,gsโ sets the gain smooth spatial radius, used to smooth gains applied to each frequency bin. useful to reduce random music noise artefacts. higher values increase smoothing of gains. allowed range is from0to50. default value is0. ๐ง
Commands
this filter supports some of the above-mentioned options as commands. yes bestie, runtime control, we love to see it ๐
Examples
- reduce white noise by 10dB, and use previously measured noise floor of -40dB:
afftdn=nr=10:nf=-40
- reduce white noise by 10dB, also set initial noise floor to -80dB and enable automatic tracking of noise floor so noise floor will gradually change during processing:
afftdn=nr=10:nf=-80:tn=1
- reduce noise by 20dB, using noise floor of -40dB and using commands to take noise profile of first 0.4 seconds of input audio:
asendcmd=0.0 afftdn sn start,asendcmd=0.4 afftdn sn stop,afftdn=nr=20:nf=-40
afftfilt
apply arbitrary expressions to samples in the frequency domain. this is the "do whatever math you want in the frequency domain" filter and it's honestly iconic ๐
realโ sets the frequency domain real expression for each separate channel, separated by'|'. default is"re". if the number of input channels is greater than the number of expressions, the last specified expression is used for the remaining output channels.imagโ sets the frequency domain imaginary expression for each separate channel, separated by'|'. default is"im".
each expression in real and imag can contain these constants and functions:
srโ sample ratebโ current frequency bin numbernbโ number of available binschโ channel number of the current expressionchsโ number of channelsptsโ current frame ptsreโ current real part of frequency bin of current channelimโ current imaginary part of frequency bin of current channelreal(b, ch)โ return the value of real part of frequency bin at location(bin,channel)imag(b, ch)โ return the value of imaginary part of frequency bin at location(bin,channel)win_sizeโ sets window size. allowed range is from16to131072. default is4096win_funcโ sets the window function. it accepts these values:rect,bartlett,hann,hanning,hamming,blackman,welch,flattop,bharris,bnuttall,bhann,sine,nuttall,lanczos,gauss,tukey,dolph,cauchy,parzen,poisson,bohman,kaiser. default is"hann". that's a lot of windows, and not one of them is the kind you look through ๐ชoverlapโ sets window overlap. if set to1, the recommended overlap for the selected window function will be picked. default is0.75.
Examples
- leave almost only low frequencies in audio:
afftfilt="'real=re * (1-clip((b/nb)*b,0,1))':imag='im * (1-clip((b/nb)*b,0,1))'"
- apply robotize effect:
afftfilt="real='hypot(re,im)*sin(0)':imag='hypot(re,im)*cos(0)':win_size=512:overlap=0.75"
- apply whisper effect:
afftfilt="real='hypot(re,im)*cos((random(0)*2-1)*2*3.14)':imag='hypot(re,im)*sin((random(1)*2-1)*2*3.14)':win_size=128:overlap=0.8"
- apply phase shift:
afftfilt="real=re*cos(1)-im*sin(1):imag=re*sin(1)+im*cos(1)"
afir
apply an arbitrary Finite Impulse Response filter. ๐
this filter is designed for applying long FIR filters, up to 60 seconds long.
it can be used as a component for digital crossover filters, room equalization, cross talk cancellation, wavefield synthesis, auralization, ambiophonics, ambisonics and spatialization. like, it does a lot.
this filter uses the streams higher than the first one as FIR coefficients. if the non-first stream holds a single channel, it will be used for all input channels in the first stream, otherwise the number of channels in the non-first stream must be same as the number of channels in the first stream.
it accepts these parameters:
dryโ set dry gain. this sets input gain.wetโ set wet gain. this sets final output gain.lengthโ set Impulse Response filter length. default is1, which means whole IR is processed.gtypeโ โ ๏ธ this option is deprecated, and does nothing. she's retired, leave her alone ๐irnormโ set norm to be applied to IR coefficients before filtering. allowed range is from-1to2. IR coefficients are normalized with the calculated vector norm set by this option. for negative values, no norm is calculated, and IR coefficients are not modified at all. default is1.irlinkโ for multichannel IR, if this option is set to true, all IR channels will be normalized with the maximal measured gain of all IR channels coefficients as set by theirnormoption. when disabled, all IR coefficients in each IR channel will be normalized independently. default istrue.irgainโ set gain to be applied to IR coefficients before filtering. allowed range is0to1. this gain is applied after any gain applied with theirnormoption.irfmtโ set format of IR stream. can be"mono"or"input". default is"input".maxirโ set max allowed Impulse Response filter duration in seconds. default is30seconds. allowed range is0.1to60seconds.responseโ โ ๏ธ this option is deprecated, and does nothing.channelโ โ ๏ธ this option is deprecated, and does nothing.sizeโ โ ๏ธ this option is deprecated, and does nothing.rateโ โ ๏ธ this option is deprecated, and does nothing.
(four for four on the do-nothing squad, no cap ๐)
minpโ set minimal partition size used for convolution. default is8192. allowed range is from1to65536. lower values decrease latency at the cost of higher CPU usage.maxpโ set maximal partition size used for convolution. default is8192. allowed range is from8to65536. lower values may increase CPU usage.nbirsโ set the number of input impulse response streams which will be switchable at runtime. allowed range is from1to32. default is1.irโ set the IR stream which will be used for convolution, starting from0, and it should always be lower than the value supplied by thenbirsoption. default is0. this option can be changed at runtime via commands. main character energy fr ๐ฅprecisionโ set which precision to use when processing samples. it accepts these values:autoโ auto pick internal sample format depending on other filters.floatโ always use single-floating point precision sample format.doubleโ always use double-floating point precision sample format.
default value is auto.
irloadโ set when to load the IR stream. can be"init"or"access". the first one loads and prepares all IRs on initialization, the second one once on first access of a specific IR. default is"init".
Examples
- apply reverb to stream using mono IR file as second input, complete command using ffmpeg:
ffmpeg -i input.wav -i middle_tunnel_1way_mono.wav -lavfi afir output.wav
- apply true stereo processing given an input stereo stream, and two stereo impulse responses for left and right channel, where the impulse response files are files with names
l_ir.wavandr_ir.wav, and setting theirnormoption value:
"pan=4C|c0=FL|c1=FL|c2=FR|c3=FR[a];amovie=l_ir.wav[LIR];amovie=r_ir.wav[RIR];[LIR][RIR]amerge[ir];[a][ir]afir=irfmt=input:irnorm=1.2,pan=stereo|FL<c0+c2|FR<c1+c3"
- similar to the above example, but with
"irgain"explicitly set to an estimated value and with"irnorm"disabled:
"pan=4C|c0=FL|c1=FL|c2=FR|c3=FR[a];amovie=l_ir.wav[LIR];amovie=r_ir.wav[RIR];[LIR][RIR]amerge[ir];[a][ir]afir=irfmt=input:irgain=-5dB:irnom=-1,pan=stereo|FL<c0+c2|FR<c1+c3"
okay real talk, that last one literally saysirnom=-1โ yes,irnom, notirnorm. that's straight from the source bestie, copy it exactly as shown and don't come for me about the spelling ๐ญ
aformat
set output format constraints for the input audio. the framework will negotiate the most appropriate format to minimize conversions. she's a negotiator, a diplomat, a peacemaker ๐ซถ
it accepts these parameters:
sample_fmts,fโ a'|'-separated list of the sample formats you're asking for ๐sample_rates,rโ a'|'-separated list of the sample rates you want โจchannel_layouts,clโ a'|'-separated list of channel layouts, bestie ๐
Check the Channel Layout section in the ffmpeg-utils(1) manual for the exact syntax you need, iykyk.
If you just... don't mention a parameter? Then literally all values are allowed. No cap. ๐ฆ
Wanna force the output to be either unsigned 8-bit or signed 16-bit stereo? Say less:
aformat=sample_fmts=u8|s16:channel_layouts=stereo
๐ธ afreqshift ๐ธ
Applies a frequency shift to your input audio samples. Iconic.
The filter accepts these options:
shiftโ sets the frequency shift. Allowed range is-INT_MAXtoINT_MAX. Default value is0.0๐๏ธlevelโ sets the output gain applied to the final output. Allowed range is from0.0to1.0. Default value is1.0๐ฅorderโ sets the filter order used for filtering. Allowed range is from1to16. Default is8โญ
Commands
This filter supports all of the above options as commands, fr fr ๐
๐ง afwtdn ๐ง
Reduces broadband noise from your input samples using Wavelets. It's giving noise-cancelling headphones but make it DSP.
Here's what the accepted options do:
sigmaโ sets the noise sigma. Allowed range is from0to1. Default value is0. This option controls the strength of the denoising applied to your input samples. The most useful way to set this is via decibels, e.g.-45dB๐levelsโ sets the number of wavelet levels of decomposition. Allowed range is from1to12. Default is10. Heads up: setting this too low makes the denoising performance very poor ๐ญwavetโ sets the wavelet type used for decomposition of the input frame. They're sorted by number of coefficients, from lowest to highest. More coefficients means worse filtering speed, but overall better quality. The available wavelets are:sym2sym4rbior68deb10sym10coif5bl3
percentโ sets the percent of full denoising. Allowed range is from0to100percent. Default value is85percent, aka partial denoising โจprofileโ if enabled, the first input frame will be used as the noise profile. Fair warning: if that first frame's samples contain non-noise, performance will be very poor ๐adaptiveโ if enabled, input frames get analyzed for the presence of noise. If noise is detected with high possibility, then that input frame profile gets used for processing the following frames, until a new noise frame is detected ๐ฆsamplesโ sets the size of a single frame in number of samples. Allowed range is from512to65536. Default frame size is8192samples ๐softnessโ sets the softness applied inside the thresholding function. Allowed range is from0to10. Default softness is1๐ธ
Commands
This filter supports all of the above options as commands ๐
๐ฅ agate ๐ฅ
A gate is mainly used to reduce the lower parts of a signal. This kind of signal processing reduces that annoying disturbing noise between your useful signals. Main character energy: only the loud stuff gets to pass.
Gating works by detecting the volume below a chosen level threshold and dividing it by the factor set with ratio. The bottom of the noise floor is set via range. And because an exact manipulation of the signal would cause distortion of the waveform, the reduction can be levelled over time โ that's what attack and release are for, bestie.
attack determines how long the signal has to fall below the threshold before any reduction will occur, and release sets the time the signal has to rise above the threshold to reduce the reduction again. Signals shorter than the chosen attack time will be left untouched ๐ซถ
level_inโ sets the input level before filtering. Default is1. Allowed range is from0.015625to64๐๏ธmodeโ sets the mode of operation. Can be"upward"or"downward". Default is"downward". If you set"upward"mode, the higher parts of the signal get amplified, expanding the dynamic range in the upward direction. Otherwise, in the"downward"case, the lower parts of the signal get reduced โฌ๏ธโฌ๏ธrangeโ sets the level of gain reduction when the signal is below the threshold. Default is0.06125. Allowed range is from0to1. Setting this to0disables reduction, and then the filter behaves like an expander ๐thresholdโ if a signal rises above this level, the gain reduction is released. Default is0.125. Allowed range is from0to1๐ratioโ sets a ratio by which the signal is reduced. Default is2. Allowed range is from1to9000๐ขattackโ the amount of milliseconds the signal has to rise above the threshold before gain reduction stops. Default is20milliseconds. Allowed range is from0.01to9000โฑ๏ธreleaseโ the amount of milliseconds the signal has to fall below the threshold before the reduction is increased again. Default is250milliseconds. Allowed range is from0.01to9000โณmakeupโ sets the amount of amplification of the signal after processing. Default is1. Allowed range is from1to64โจkneeโ curves the sharp knee around the threshold so you enter gain reduction more softly. Default is2.828427125. Allowed range is from1to8๐detectionโ choose whether the exact signal should be taken for detection or an RMS-like one. Default is"rms". Can be"peak"or"rms"๐linkโ choose whether the average level between all channels or the louder channel affects the reduction. Default is"average". Can be"average"or"maximum"๐
Commands
This filter supports all of the above options as commands ๐
๐ฆ aiir ๐ฆ
Applies an arbitrary Infinite Impulse Response filter. Very math, very slay.
It accepts these parameters:
zeros,zโ sets B/numerator/zeros/reflection coefficients ๐ขpoles,pโ sets A/denominator/poles/ladder coefficients ๐ขgains,kโ sets channels gains ๐๏ธdry_gainโ sets input gain ๐wet_gainโ sets output gain โจformat,fโ sets coefficients format:llโ lattice-ladder functionsfโ analog transfer functiontfโ digital transfer functionzpโ Z-plane zeros/poles, cartesian (default)prโ Z-plane zeros/poles, polar radianspdโ Z-plane zeros/poles, polar degreesspโ S-plane zeros/poles
process,rโ sets type of processing:dโ direct processingsโ serial processingpโ parallel processing
precision,eโ sets filtering precision:dblโ double-precision floating-point (default)fltโ single-precision floating-pointi32โ 32-bit integersi16โ 16-bit integers
normalize,nโ normalize filter coefficients, enabled by default. Enabling it will normalize the magnitude response at DC to0dB๐mixโ how much to use the filtered signal in the output. Default is1. Range is between0and1๐๏ธresponseโ show IR frequency response, magnitude (magenta), phase (green) and group delay (yellow) in an additional video stream. By default it's disabled ๐channelโ set for which IR channel to display the frequency response. By default the first channel is displayed. This option is only used whenresponseis enabled ๐sizeโ set video stream size. This option is only used whenresponseis enabled ๐
Coefficients in "tf" and "sf" format are separated by spaces and are in ascending order. Periodt.
Coefficients in "zp" format are separated by spaces and the order of the coefficients doesn't matter. Coefficients in "zp" format are complex numbers with i as the imaginary unit, iykyk ๐งฎ
Different coefficients and gains can be provided for every channel โ in that case use '|' to separate the coefficients or gains. The last provided coefficients will be used for all the remaining channels ๐ซถ
Examples
- Apply a 2 pole elliptic notch at around
5000Hzfor48000 Hzsample rate:
aiir=k=1:z=7.957584807809675810E-1 -2.575128568908332300 3.674839853930788710 -2.57512875289799137 7.957586296317130880E-1:p=1 -2.86950072432325953 3.63022088054647218 -2.28075678147272232 6.361362326477423500E-1:f=tf:r=d
- Same as above but in
"zp"format:
aiir=k=0.79575848078096756:z=0.80918701+0.58773007i 0.80918701-0.58773007i 0.80884700+0.58784055i 0.80884700-0.58784055i:p=0.63892345+0.59951235i 0.63892345-0.59951235i 0.79582691+0.44198673i 0.79582691-0.44198673i:f=zp:r=s
- Apply a 3-rd order analog normalized Butterworth low-pass filter, using the analog transfer function format:
aiir=z=1.3057 0 0 0:p=1.3057 2.3892 2.1860 1:f=sf:r=d
๐ alimiter ๐
The limiter prevents an input signal from rising over a desired threshold. This limiter uses lookahead technology to keep your signal from distorting. Which means... there's a small delay after the signal is processed. Keep in mind that the delay it produces is the attack time you set, bestie โ don't say I didn't warn you ๐ญ
The filter accepts these options:
level_inโ sets input gain. Default is1๐๏ธlevel_outโ sets output gain. Default is1๐๏ธlimitโ don't let signals above this level pass the limiter. Default is1๐attackโ the limiter will reach its attenuation level in this amount of time, in milliseconds. Default is5milliseconds โฑ๏ธreleaseโ come back from limiting to attenuation1.0in this amount of milliseconds. Default is50milliseconds โณascโ when gain reduction is always needed, ASC takes care of releasing to an average reduction level rather than reaching a reduction of0in the release time ๐asc_levelโ select how much the release time is affected by ASC.0means nearly no changes in release time, while1produces higher release times ๐levelโ auto level output signal. Default is enabled. This normalizes audio back to0dBif enabled โจlatencyโ compensate the delay introduced by using the lookahead buffer set with theattackparameter. Also flush the valid audio data in the lookahead buffer when the stream hits EOF ๐ซถ
Depending on the setting you pick, it's recommended to upsample the input2xor4xtimes witharesamplebefore applying this filter. No cap, take the advice ๐ฅ
โญ allpass โญ
Applies a two-pole all-pass filter with central frequency (in Hz) frequency, and filter-width width. An all-pass filter changes the audio's frequency-to-phase relationship without changing its frequency-to-amplitude relationship. It's giving "same energy, different vibe" ๐ซ
The filter accepts these options:
frequency,fโ set frequency in Hz ๐ตwidth_type,tโ set the method to specify the band-width of the filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specify the band-width of a filter in width_type units ๐mix,mโ how much to use the filtered signal in the output. Default is1. Range is between0and1๐๏ธchannels,cโ which channels are we even filtering bestie? default is all available ones. slay.normalize,nโ normalizes the biquad coefficients. default? disabled ๐. turn it on and the magnitude response at DC gets normalized to 0dB. cute.order,oโ sets the filter order. it can be1or2. default is2. that's it that's the option ๐transform,aโ sets the transform type of the IIR filter. the options are:didiitditdiilattsvfzdf
precision,rโ sets the precision of the filtering. pick your fighter:autoโ picks the automatic sample format depending on the surround filters โจs16โ always use signed 16-bit.s32โ always use signed 32-bit.f32โ always use float 32-bit.f64โ always use float 64-bit.
Commands ๐ฌ
this filter supports the following commands, bestie:
frequency,fโ change the allpass frequency. syntax for the command is:"frequency"width_type,tโ change the allpass width_type. syntax for the command is:"width_type"width,wโ change the allpass width. syntax for the command is:"width"mix,mโ change the allpass mix. syntax for the command is:"mix"
๐ aloop
loops audio samples. living that replay life, no cap.
the filter accepts these options:
loopโ sets the number of loops. setting it to-1gives you infinite loops (main character energy, it never ends ๐). default is0.sizeโ sets the maximal number of samples. default is0.startโ sets the first sample of the loop. default is0.timeโ sets the time of the loop start in seconds. only used if the option namedstartis set to-1.
๐ซ amerge
merges two or more audio streams into a single multi-channel stream. friendship bracelet behavior ๐ซถ.
all inputs must have the same sample rate, and format. non-negotiable.
if the inputs don't have the same duration, the output will stop with the shortest one. sad but true ๐ญ.
the filter accepts the following options:
inputsโ sets the number of inputs. default is2.layout_modeโ controls how the output channel layout is determined and whether the audio channels get reordered during the merge. three modes, all valid, all iconic:legacyโ this is the mode where the filter behaved historically, so it's the default.
if the channel layouts of the inputs are known and disjoint, and therefore compatible, the channel layout of the output will be set accordingly and the channels will be reordered as necessary. if the channel layouts of the inputs are not disjoint, some of them are unknown, or they're using special channel layouts such as ambisonics, the output will have all the channels of the first input then all the channels of the second input, in that order, and the channel layout of the output will be the default value corresponding to the total number of channels.
for example, if the first input is in 2.1 (FL+FR+LF) and the second input is FC+BL+BR, then the output will be in 5.1, with the channels in this order: a1, a2, b1, a3, b2, b3 (a1 is the first channel of the first input, b1 is the first channel of the second input).
on the other hand, if both inputs are in stereo, the output channels will be in the default order: a1, a2, b1, b2, and the channel layout will be arbitrarily set to 4.0, which may or may not be the expected value. lowkey a gamble ๐.
resetโ this mode ignores the input channel layouts and does no channel reordering. the output will have all the channels of the first input, then all the channels of the second input, in that order, and so on.
the output channel layout will only specify the total channel count.
normalโ this mode keeps channel name and designation information from the input channels and does no channel reordering. the output will have all the channels of the first input, then all the channels of the second input, in that order, and so on.
Examples โจ
- merge two mono files into a stereo stream:
amovie=left.wav [l] ; amovie=right.mp3 [r] ; [l] [r] amerge
- multiple merges assuming 1 video stream and 6 audio streams in
input.mkv:
ffmpeg -i input.mkv -filter_complex "[0:1][0:2][0:3][0:4][0:5][0:6] amerge=inputs=6" -c:a pcm_s16le output.mkv
๐ง amix
mixes multiple audio inputs into a single output. the group chat merge feature fr fr.
heads up bestie: this filter only supports float samples (theamergeandpanaudio filters support many formats). if theamixinput has integer samples thenaresamplewill be automatically inserted to perform the conversion to float samples. it's giving helpful.
it accepts the following parameters:
inputsโ the number of inputs. if unspecified, it defaults to2.durationโ how to determine the end-of-stream:longestโ the duration of the longest input. (default)shortestโ the duration of the shortest input.firstโ the duration of the first input.
dropout_transitionโ the transition time, in seconds, for volume renormalization when an input stream ends. default value is2seconds.weightsโ specify the weight of each input audio stream as a sequence of numbers separated by a space. if fewer weights are specified compared to the number of inputs, the last weight is assigned to the remaining inputs. default weight for each input is1.normalizeโ always scale inputs instead of only doing summation of samples. โ ๏ธ beware of heavy clipping if inputs are not normalized prior to or after filtering by this filter if this option is disabled. by default it's enabled. protect your ears ๐.
Examples ๐ธ
- this will mix 3 input audio streams to a single output with the same duration as the first input and a dropout transition time of 3 seconds:
ffmpeg -i INPUT1 -i INPUT2 -i INPUT3 -filter_complex amix=inputs=3:duration=first:dropout_transition=3 OUTPUT
- this will mix one vocal and one music input audio stream to a single output with the same duration as the longest input. the music will have quarter the weight as the vocals, and the inputs are not normalized:
ffmpeg -i VOCALS -i MUSIC -filter_complex amix=inputs=2:duration=longest:dropout_transition=0:weights="1 0.25":normalize=0 OUTPUT
Commands ๐ฌ
this filter supports the following commands:
weightsnormalize
syntax is same as the option with the same name. easy.
โ๏ธ amultiply
multiplies the first audio stream with the second audio stream and stores the result in the output audio stream. the multiplication is done by multiplying each sample from the first stream with the sample at the same position from the second stream.
with this element-wise multiplication you can create amplitude fades and amplitude modulations. math but make it fashion ๐ .
๐๏ธ anequalizer
high-order parametric multiband equalizer for each channel. the glow-up filter, literally.
it accepts the following parameters:
paramsโ this option string is in the format:"cchn f=cf w=w g=g t=f | ..."each equalizer band is separated by'|'.chnโ set the channel number to which equalization will be applied. if the input doesn't have that channel the entry is ignored. rude but okay.fโ set the central frequency for the band. if the input doesn't have that frequency the entry is ignored.wโ set the band width in Hertz.gโ set the band gain in dB.tโ set the filter type for the band, optional, can be:0โ Butterworth, this is default.1โ Chebyshev type 1.2โ Chebyshev type 2.
curvesโ with this option activated the frequency response ofanequalizeris displayed in the video stream. visualization slay ๐.sizeโ set the video stream size. only useful if thecurvesoption is activated.mgainโ set the max gain that will be displayed. only useful if thecurvesoption is activated. setting this to a reasonable value makes it possible to display gain which is derived from neighbour bands which are too close to each other and thus produce higher gain when both are activated.fscaleโ set the frequency scale used to draw the frequency response in the video output. can belinearorlogarithmic. default islogarithmic.colorsโ set the color for each channel curve which is going to be displayed in the video stream. this is a list of color names separated by space or by'|'. unrecognised or missing colors will be replaced by white color. default? white. always white. ๐ค
Examples ๐ฆ
- lower gain by 10 of central frequency 200Hz and width 100 Hz for the first 2 channels using a Chebyshev type 1 filter:
anequalizer=c0 f=200 w=100 g=-10 t=1|c1 f=200 w=100 g=-10 t=1
Commands ๐ฌ
this filter supports the following commands:
changeโ alter existing filter parameters. syntax for the commands is:"fN|f=freq|w=width|g=gain"
fN is the existing filter number, starting from 0, if no such filter is available an error is returned. freq sets the new frequency parameter. width sets the new width parameter in Hertz. gain sets the new gain parameter in dB.
full filter invocation with asendcmd may look like this: asendcmd=c='4.0 anequalizer change 0|f=200|w=50|g=1',anequalizer=...
๐ anlmdn
reduces broadband noise in audio samples using the Non-Local Means algorithm. bye background hiss, you will not be missed ๐.
each sample is adjusted by looking for other samples with similar contexts. this context similarity is defined by comparing their surrounding patches of size p. patches are searched in an area of r around the sample.
the filter accepts the following options:
strength,sโ set the denoising strength. allowed range is from0.00001to10000. default value is0.00001.patch,pโ set the patch radius duration. allowed range is from1to100milliseconds. default value is2milliseconds.research,rโ set the research radius duration. allowed range is from2to300milliseconds. default value is6milliseconds.output,oโ set the output mode. it accepts the following values:iโ pass input unchanged.oโ pass noise filtered out.nโ pass only noise.
default value is o.
smooth,mโ set the smooth factor. default value is11. allowed range is from1to1000.
Commands ๐ฌ
this filter supports all the above options as commands. every single one. generous queen ๐.
๐ง anlmf, anlms
apply the Normalized Least-Mean-(Squares|Fourth) algorithm to the first audio stream using the second audio stream.
this adaptive filter is used to mimic a desired filter by finding the filter coefficients that relate to producing the least mean square of the error signal (the difference between the desired, 2nd input audio stream, and the actual signal, the 1st input audio stream). it's giving "learn from your mistakes" but make it DSP ๐.
a description of the accepted options follows.
orderโ set filter order.muโ set filter mu.epsโ sets the filter'seps. that's it, that's the whole option โจleakageโ sets the filter'sleakage.out_modeโ picks which samples actually come out the other side. it takes these values:iโ pass the 1st input. straightforward icon ๐dโ pass the 2nd input.oโ pass the difference between desired (2nd input) and the error signal estimate.nโ pass the difference between input (1st input) and the error signal estimate.eโ pass the error signal estimated samples.
default value is o. yes bestie, o is the main character here ๐
precisionโ tells the filter which precision to use when processing samples:autoโ auto pick the internal sample format depending on other filters. the lowkey reliable one ๐ซถfloatโ always use single-floating point precision sample format.doubleโ always use double-floating point precision sample format.
๐ธ Examples ๐ธ
- one of many usages of this filter is noise reduction โ input audio gets filtered with the same samples delayed by a fixed amount. one such example for stereo audio is:
asplit[a][b],[a]adelay=32S|32S[a],[b][a]anlms=order=128:leakage=0.0005:mu=.5:out_mode=o
๐ Commands ๐
this filter supports the same commands as options, excluding option "order". so don't even try it, she's not taking requests on that one ๐
anull
pass the audio source unchanged to the output. literally does nothing and honestly? respect. no notes, no drama, zero processing โจ
apad
pad the end of an audio stream with silence. like adding a lil quiet outro so nothing ends abruptly ๐ฆ
this can be used together with ffmpeg -shortest to extend audio streams to the same length as the video stream. iconic combo fr fr.
here's a description of the accepted options:
packet_sizeโ set silence packet size. default value is4096.pad_lenโ set the number of samples of silence to add to the end. after the value is reached, the stream is terminated. this option is mutually exclusive withwhole_len. they cannot both be the chosen one ๐whole_lenโ set the minimum total number of samples in the output audio stream. if the value is longer than the input audio length, silence is added to the end until the value is reached. this option is mutually exclusive withpad_len.pad_durโ specify the duration of samples of silence to add. see the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. used only if set to non-negative value.whole_durโ specify the minimum total duration in the output audio stream. see the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. used only if set to non-negative value. if the value is longer than the input audio length, silence is added to the end until the value is reached. this option is mutually exclusive withpad_dur.
if neither thepad_lennor thewhole_lennorpad_durnorwhole_duroption is set, the filter will add silence to the end of the input stream indefinitely. girl will just keep going ๐ญ like no cap, forever.
ngl, note that forffmpeg4.4 and earlier a zeropad_durorwhole_duralso caused the filter to add silence indefinitely. old behaviour, be aware ๐
๐ Examples ๐
- add
1024samples of silence to the end of the input:
apad=pad_len=1024
- make sure the audio output will contain at least
10000samples, pad the input with silence if required:
apad=whole_len=10000
- use
ffmpegto pad the audio input with silence, so that the video stream will always result the shortest and will be converted until the end in the output file when using theshortestoption:
ffmpeg -i VIDEO -i AUDIO -filter_complex "[1:0]apad" -shortest OUTPUT
aphaser
add a phasing effect to the input audio. it's giving swoosh โจ
a phaser filter creates series of peaks and troughs in the frequency spectrum. the position of the peaks and troughs are modulated so that they vary over time, creating a sweeping effect. obsessed with the sweep, honestly ๐ฅ
here's a description of the accepted parameters:
in_gainโ set input gain. default is0.4.out_gainโ set output gain. default is0.74.delayโ set delay in milliseconds. default is3.0.decayโ set decay. default is0.4.speedโ set modulation speed in Hz. default is0.5.typeโ set modulation type. default istriangular. it accepts the following values:triangular,tsinusoidal,s
aphaseshift
apply phase shift to input audio samples. shifting the vibe, literally ๐
the filter accepts the following options:
shiftโ specify phase shift. allowed range is from-1.0to1.0. default value is0.0.levelโ set output gain applied to final output. allowed range is from0.0to1.0. default value is1.0.orderโ set filter order used for filtering. allowed range is from1to16. default value is8.
๐ซถ Commands ๐ซถ
this filter supports all the above options as commands. all of them. every single one. periodt ๐
apsnr
measure Audio Peak Signal-to-Noise Ratio. it's a measurement girlie, not a filter girlie ๐
this filter takes two audio streams for input, and outputs first audio stream. results are in dB per channel at end of either input. so you feed her two streams and she tells you the numbers ๐
apsyclip
apply Psychoacoustic clipper to input audio stream. clipping, but make it science ๐ง
the filter accepts the following options:
level_inโ set input gain. by default it is1. range is[0.015625 - 64].level_outโ set output gain. by default it is1. range is[0.015625 - 64].clipโ set the clipping start value. default value is0dBFSor1.diffโ output only difference samples, useful to hear introduced distortions. by default is disabled.adaptiveโ set strength of adaptive distortion applied. default value is0.5. allowed range is from0to1.iterationsโ set number of iterations of psychoacoustic clipper. allowed range is from1to20. default value is10.levelโ auto level output signal. default is disabled. this normalizes audio back to0dBFSif enabled.
โญ Commands โญ
this filter supports all the above options as commands. yes, all of them, go off ๐
apulsator
audio pulsator is something between an autopanner and a tremolo. but it can produce funny stereo effects as well. pulsator changes the volume of the left and right channel based on a LFO (low frequency oscillator) with different waveforms and shifted phases. this filter have the ability to define an offset between left and right channel. an offset of 0 means that both LFO shapes match each other. the left and right channel are altered equally โ a conventional tremolo. an offset of 50% means that the shape of the right channel is exactly shifted in phase (or moved backwards about half of the frequency) โ pulsator acts as an autopanner. at 1 both curves match again. every setting in between moves the phase shift gapless between all stages and produces some "bypassing" sounds with sine and triangle waveforms. the more you set the offset near 1 (starting from the 0.5) the faster the signal passes from the left to the right speaker. it's giving whoosh left, whoosh right ๐ฅ๐
the filter accepts the following options:
level_inโ set input gain. by default it is1. range is[0.015625 - 64].level_outโ set output gain. by default it is1. range is[0.015625 - 64].modeโ set waveform shape the LFO will use. can be one of:sine,triangle,square,sawuporsawdown. default issine.amountโ set modulation. define how much of original signal is affected by the LFO.offset_lโ set left channel offset. default is0. allowed range is[0 - 1].offset_rโ set right channel offset. default is0.5. allowed range is[0 - 1].widthโ set pulse width. default is1. allowed range is[0 - 2].timingโ set possible timing mode. can be one of:bpm,msorhz. default ishz.bpmโ set bpm. default is120. allowed range is[30 - 300]. only used iftimingis set tobpm.msโ set ms. default is500. allowed range is[10 - 2000]. only used iftimingis set toms.hzโ set frequency in Hz. default is2. allowed range is[0.01 - 100]. only used iftimingis set tohz.
aresample
resample the input audio to the specified parameters, using the libswresample library. if none are specified then the filter will automatically convert between its input and output. she's flexible like that ๐
this filter is also able to stretch/squeeze the audio data to make it match the timestamps, or to inject silence / cut out audio to make it match the timestamps, do a combination of both, or do neither. choose your fighter ๐ฆ
the filter accepts the syntax [sample_rate:]resampler_options, where sample_rate expresses a sample rate and resampler_options is a list of key=value pairs, separated by ":". see the "Resampler Options" section in the ffmpeg-resampler(1) manual for the complete list of supported options. iykyk ๐
๐ Examples ๐
- resample the input audio to
44100Hz:
aresample=44100
- stretch/squeeze samples to the given timestamps, with a maximum of
1000samples per second compensation:
aresample=async=1000
areverse
reverse an audio clip. yes, like backwards. the drama of it all ๐ญ
Warning: this filter requires memory to buffer the entire clip, so trimming is suggested. fr fr, trim first or your RAM is gonna have a bad time ๐
๐ Examples ๐
- take the first 5 seconds of a clip, and reverse it:
atrim=end=5,areverse
arls
apply Recursive Least Squares algorithm to the first audio stream using the second audio stream. big math energy ๐งโจ
this adaptive filter is used to mimic a desired filter by recursively finding the filter coefficients that relate to producing the minimal weighted linear least squares cost function of the error signal (difference between the desired, 2nd input audio stream and the actual signal, the 1st input audio stream). yes that's a whole sentence, i read it twice so you didn't have to ๐ซถ
a description of the accepted options follows:
orderโ set the filter order.lambdaโ set the forgetting factor.deltaโ set the coefficient to initialize internal covariance matrix.out_modeโ set the filter output samples. it accepts the following values:iโ pass the 1st input.dโ pass the 2nd input.oโ pass difference between desired, 2nd input and error signal estimate.nโ pass difference between input, 1st input and error signal estimate.eโ pass error signal estimated samples.
default value is o. again. o stays winning ๐
precisionโ set which precision to use when processing samples:autoโ auto pick internal sample format depending on other filters.floatโ always use single-floating point precision sample format.doubleโ always use double-floating point precision sample format.
arnndn
reduce noise from speech using Recurrent Neural Networks. the neural net is literally doing the "shhh" for you ๐คซโจ
this filter accepts the following options:
model,mโ set train model file to load. this option is always required. like, non-negotiable, she will not run without it ๐mixโ sets how much of the filtered samples get mixed into the final output ๐ซถ Allowed range is-1to1, default is1. Ngl the negative values are the special little gremlins here: they set how much filtered noise to keep in the final filter output. Want to actually hear the noise that got removed from your input signal? Set this to-1and enjoy the chaos ๐
Commands
This filter supports all the above options as commands โจ
๐ง asdr
Measures the Audio Signal-to-Distortion Ratio fr fr.
This filter takes two audio streams as input, and outputs the first audio stream ๐ Results are in dB per channel at the end of either input.
๐๏ธ asetnsamples
Sets the number of samples per each output audio frame.
Heads up bestie: the last output packet may contain a different number of samples, because the filter flushes out all the remaining samples when the input audio signals its end ๐ธ
The filter accepts the following options:
nb_out_samples,nโ the number of frames per each output audio frame. This number is meant as the number of samples per each channel. Default is1024.pad,pโ if set to1, the filter pads the last audio frame with zeroes so the last frame has the same number of samples as all the previous ones. Default is1.
For example, to set the number of per-frame samples to 1234 and disable padding for the last frame, do:
asetnsamples=n=1234:p=0
๐ asetrate
Sets the sample rate without altering the PCM data. The way this works, it'll cause a change of speed and pitch โ yes, both, that's the vibe ๐ญ
It accepts these options:
sample_rate,rโ set the output sample rate. Default is44100Hz.
๐ ashowinfo
Shows a line containing all kinds of info for each input audio frame ๐ The input audio itself is not modified, she's just observing.
The shown line is a sequence of key/value pairs of the form key:value.
These are the values shown in the output:
nโ the (sequential) number of the input frame, starting from0.ptsโ the presentation timestamp of the input frame, in time base units. The time base depends on the filter input pad, and is usually1/sample_rate.pts_timeโ the presentation timestamp of the input frame, in seconds.fmtโ the sample format.chlayoutโ the channel layout.rateโ the sample rate for the audio frame.nb_samplesโ the number of samples (per channel) in the frame.checksumโ the Adler-32 checksum (printed in hexadecimal) of the audio data. For planar audio, the data is treated as if all the planes were concatenated ๐ซถplane_checksumsโ a list of Adler-32 checksums for each data plane.
๐ asisdr
Measures Audio Scaled-Invariant Signal-to-Distortion Ratio โจ
This filter takes two audio streams as input, and outputs the first audio stream. Results are in dB per channel at the end of either input ๐
๐๏ธ asoftclip
Applies audio soft clipping.
Soft clipping is a type of distortion effect where the amplitude of a signal gets saturated along a smooth curve, rather than the abrupt shape of hard-clipping โ think cozy rounded edges instead of a jagged little cliff ๐ฅ
This filter accepts the following options:
typeโ set the type of soft-clipping.
It accepts the following values:
hardtanhatancubicexpalgquinticsinerf
thresholdโ set the threshold from where to start clipping. Default is0dBor1.outputโ set gain applied to output. Default is0dBor1.paramโ set an additional parameter which controls the sigmoid function.oversampleโ set oversampling factor.
Commands
This filter supports all the above options as commands ๐
๐ aspectralstats
Displays frequency domain statistical information about the audio channels. Stats are calculated and stored as metadata for each audio channel and for each audio frame ๐
It accepts the following option:
win_sizeโ set the window length in samples. Default is2048. Allowed range is32to65536.win_funcโ set the window function.
It accepts the following values:
rectbartletthann,hanninghammingblackmanwelchflattopbharrisbnuttallbhannsinenuttalllanczosgausstukeydolphcauchyparzenpoissonbohmankaiser
Default is "hann".
overlapโ set window overlap. Allowed range is0to1. Default is0.5.measureโ select the parameters which are measured. The metadata keys can be used as flags; default isall, which measures everything.nonedisables all measurement.
A list of each metadata key follows:
meanvariancecentroidspreadskewnesskurtosisentropyflatnesscrestfluxslopedecreaserolloff
๐ฃ๏ธ asr
Automatic Speech Recognition ๐ค
This filter uses PocketSphinx for speech recognition. To enable compilation of this filter, you need to configure FFmpeg with --enable-pocketsphinx.
It accepts the following options:
rateโ set the sampling rate of the input audio. Default is16000. This needs to match the speech models, otherwise you'll get poor results ๐ญhmmโ set the dictionary containing acoustic model files.dictโ set the pronunciation dictionary.lmโ set the language model file.lmctlโ set the language model set.lmnameโ set which language model to use.logfnโ set output for log messages.
The filter exports recognized speech as the frame metadata lavfi.asr.text ๐
๐ astats
Displays time domain statistical information about the audio channels. Statistics are calculated and displayed for each audio channel and, where applicable, an overall figure is also given ๐
It accepts the following option:
lengthโ short window length in seconds, used for peak and through RMS measurement. Default is0.05(50 milliseconds). Allowed range is[0 - 10].metadataโ set metadata injection. All metadata keys are prefixed withlavfi.astats.X, whereXis the channel number starting from1or the stringOverall. Default is disabled.
Available keys for each channel are: Bit_depth Crest_factor DC_offset Dynamic_range Entropy Flat_factor Max_difference Max_level Mean_difference Min_difference Min_level Noise_floor Noise_floor_count Number_of_Infs Number_of_NaNs Number_of_denormals Peak_count Abs_Peak_count Peak_level RMS_difference RMS_peak RMS_trough Zero_crossings Zero_crossings_rate
and for Overall: Bit_depth DC_offset Entropy Flat_factor Max_difference Max_level Mean_difference Min_difference Min_level Noise_floor Noise_floor_count Number_of_Infs Number_of_NaNs Number_of_denormals Number_of_samples Peak_count Abs_Peak_count Peak_level RMS_difference RMS_level RMS_peak RMS_trough
For example, a full key looks like lavfi.astats.1.DC_offset or lavfi.astats.Overall.Peak_count โจ
Read below for the description of the keys.
resetโ set the number of frames over which cumulative stats are calculated before being reset. Default is disabled.measure_perchannelโ select the parameters which are measured per channel. The metadata keys can be used as flags; default isall, which measures everything.nonedisables all per-channel measurement.measure_overallโ select the parameters which are measured overall. The metadata keys can be used as flags; default isall, which measures everything.nonedisables all overall measurement.
A description of the measure keys follows:
noneโ no measures.allโ all measures.Bit_depthโ overall bit depth of audio, i.e. number of bits used for each sample.Crest_factorโ standard ratio of peak to RMS level (note: not in dB).DC_offsetโ mean amplitude displacement from zero.Dynamic_rangeโ measured dynamic range of audio in dB.Entropyโ entropy measured across the whole audio; entropy of a value near1.0is typically measured for white noise.Flat_factorโ flatness (i.e. consecutive samples with the same value) of the signal at its peak levels (i.e. eitherMin_levelorMax_level).Max_differenceโ maximal difference between two consecutive samples.Max_levelโ maximal sample level.Mean_differenceโ mean difference between two consecutive samples, i.e. the average of each difference between two consecutive samples.Min_differenceโ minimal difference between two consecutive samples.Min_levelโ minimal sample level.Noise_floorโ minimum local peak measured in dBFS over a short window.Noise_floor_countโ number of occasions (not the number of samples) that the signal attained the noise floor.Number_of_Infsโ number of samples with an infinite value.Number_of_NaNsโ number of samples with a NaN (not a number) value.Number_of_denormalsโ number of samples with a subnormal value.Number_of_samplesโ number of samples.Peak_countโ number of occasions (not the number of samples) that the signal attained eitherMin_levelorMax_level.Abs_Peak_countโ number of occasions that the absolute samples taken from the signal attained the max absolute value ofMin_levelandMax_level.Peak_levelโ standard peak level measured in dBFS.RMS_differenceโ Root Mean Square difference between two consecutive samples.RMS_levelโ standard RMS level measured in dBFS.RMS_peak,RMS_troughโ peak and through values for RMS level measured over a short window, measured in dBFS.Zero crossingsโ number of points where the waveform crosses the zero level axis.Zero crossings rateโ rate of zero crossings and number of audio samples.
๐ asubboost
Boosts subwoofer frequencies ๐ถ
The filter accepts the following options:
dryโ set dry gain, i.e. how much of the original signal is kept. Allowed range is0to1. Default is1.0.wetโ set wet gain, i.e. how much of the filtered signal is kept. Allowed range is0to1. Default is1.0.boostโ set max boost factor. Allowed range is1to12. Default is2.decayโ set delay line decay gain value. Allowed range is0to1. Default is0.0.feedbackโ set delay line feedback gain value. Allowed range is0to1. Default is0.9.cutoffโ set cutoff frequency in Hertz. Allowed range is50to900. Default is100.slopeโ sets how much slope the cutoff frequency gets. Allowed range is0.0001to1, and the default is0.5. โจdelayโ sets the delay, bestie. Allowed range is from1to100, default20.channelsโ which channels get processed. Default is literally all the available ones, no notes. ๐
Commands ๐ฌ
This filter supports the all above options as commands โ yes, every single one of those, go off.
asubcut ๐
Cuts subwoofer frequencies. Like, bye to the rumble.
The whole point of this one: it lets you set a custom, steeper roll off than the highpass filter does, so it's way better at attenuating frequency content in the stop-band. It's giving surgical. ๐ฆ
The filter accepts the following options:
cutoffโ sets the cutoff frequency in Hertz. Allowed range is2to200, default20.orderโ sets the filter order. Available values are from3to20, default10.levelโ sets the input gain level. Allowed range is from0to1, default1.
Commands ๐ฌ
This filter supports the all above options as commands. periodt.
asupercut ๐
Cuts super frequencies. High-pitch girlies, your time is up.
The filter accepts the following options:
cutoffโ sets the cutoff frequency in Hertz. Allowed range is20000to192000, default20000.orderโ sets the filter order. Available values are from3to20, default10.levelโ sets the input gain level. Allowed range is from0to1, default1.
Commands ๐ฌ
This filter supports the all above options as commands. slay.
asuperpass ๐ธ
Applies a high order Butterworth band-pass filter. Fancy filter, fancy name, we love her.
The filter accepts the following options:
centerfโ sets the center frequency in Hertz. Allowed range is2to999999, default1000.orderโ sets the filter order. Available values are from4to20, default4.qfactorโ sets the Q-factor. Allowed range is from0.01to100, default1.levelโ sets the input gain level. Allowed range is from0to2, default1.
Commands ๐ฌ
This filter supports the all above options as commands. no cap.
asuperstop ๐
Applies a high order Butterworth band-stop filter. Same energy as above but it's the stop one, iykyk.
The filter accepts the following options:
centerfโ sets the center frequency in Hertz. Allowed range is2to999999, default1000.orderโ sets the filter order. Available values are from4to20, default4.qfactorโ sets the Q-factor. Allowed range is from0.01to100, default1.levelโ sets the input gain level. Allowed range is from0to2, default1.
Commands ๐ฌ
This filter supports the all above options as commands. ๐
atempo ๐ฅ
Adjusts audio tempo. The vibes-speed dial.
The filter accepts exactly one parameter: the audio tempo. If you don't specify it, the filter will assume a nominal 1.0 tempo. Tempo must be in the [0.5, 100.0] range. That's the whole range, that's the whole rule.
Heads up bestie ๐ซถ โ note that a tempo greater than2will skip some samples rather than blend them in. If for any reason that's a concern, it's always possible to daisy-chain several instances ofatempoto achieve the desired product tempo. Chain her up.
Examples โจ
- Slow down audio to 80% tempo:
atempo=0.8
- To speed up audio to 300% tempo:
atempo=3
- To speed up audio to 300% tempo by daisy-chaining two atempo instances:
atempo=sqrt(3),atempo=sqrt(3)
Commands ๐ฌ
This filter supports the following commands:
tempoโ change filter tempo scale factor. Syntax for the command is :"tempo".
atilt ๐ฆ
Applies a spectral tilt filter to the audio stream. It's giving main character audio glow-up.
This filter applies any spectral roll-off slope over any specified frequency band. Any slope, any band, we're flexible like that.
The filter accepts the following options:
freqโ sets the central frequency of the tilt in Hz. Default is10000Hz.slopeโ sets the slope direction of the tilt. Default is0. Allowed range is from-1to1.widthโ sets the width of the tilt. Default is1000. Allowed range is from100to10000.orderโ sets the order of the tilt filter.levelโ sets the input volume level. Allowed range is from0to4, default is1.
Commands ๐ฌ
This filter supports the all above options as commands. ๐
atrim โ๏ธ
Trims the input so the output contains one continuous subpart of the input. One clean little piece, nothing extra.
It accepts the following parameters:
startโ timestamp (in seconds) of the start of the section to keep. I.e. the audio sample with the timestamp start will be the first sample in the output.endโ specify the time of the first audio sample that will be dropped, i.e. the audio sample immediately preceding the one with the timestamp end will be the last sample in the output.start_ptsโ same asstart, except this option sets the start timestamp in samples instead of seconds.end_ptsโ same asend, except this option sets the end timestamp in samples instead of seconds.durationโ the maximum duration of the output in seconds.start_sampleโ the number of the first sample that should be output.end_sampleโ the number of the first sample that should be dropped.
start, end, and duration are expressed as time duration specifications; see the Time duration section in the ffmpeg-utils(1) manual. ๐
Okay so here's the part that matters ๐ญ โ note that the first two sets of thestart/endoptions and thedurationoption look at the frame timestamp, while the_sampleoptions simply count the samples that pass through the filter. Sostart/end_ptsandstart/end_samplewill give you different results when the timestamps are wrong, inexact, or don't start at zero. Also note that this filter does not modify the timestamps. If you want the output timestamps to start at zero, insert theasetptsfilter after theatrimfilter. That's the move. ๐
If multiple start or end options are set, this filter tries to be greedy and keep all samples that match at least one of the specified constraints. To keep only the part that matches all the constraints at once, chain multiple atrim filters. Greedy queen.
The defaults are such that all the input is kept. So it's possible to set, e.g., just the end values to keep everything before the specified time. Obsessed with a low-effort config.
Examples โจ
- Drop everything except the second minute of input:
ffmpeg -i INPUT -af atrim=60:120
- Keep only the first 1000 samples:
ffmpeg -i INPUT -af atrim=end_sample=1000
axcorrelate ๐ง
Calculates the normalized windowed cross-correlation between two input audio streams. Two streams, one glow-up.
Resulted samples are always between -1 and 1 inclusive, fr fr:
- If the result is
1, it means two input samples are highly correlated in that selected segment. - Result
0means they are not correlated at all. - If the result is
-1, it means two input samples are out of phase, which means they cancel each other. ๐
The filter accepts the following options:
sizeโ sets the size of the segment over which cross-correlation is calculated. Default is256. Allowed range is from2to131072.algoโ sets the algorithm for cross-correlation. Can be"slow"or"fast"or"best". Default is"best". The fast algorithm assumes mean values over any given segment are always zero and thus needs much less calculation to make. This is generally not true, but it's valid for typical audio streams. (Valid โ always true, bestie, that's the whole tea. ๐)
Examples โจ
- Calculate correlation between channels in stereo audio stream:
ffmpeg -i stereo.wav -af channelsplit,axcorrelate=size=1024:algo=fast correlation.wav
bandpass ๐
Applies a two-pole Butterworth band-pass filter with central frequency frequency, and (3dB-point) band-width width. The csg option selects a constant skirt gain (peak gain = Q) instead of the default: constant 0dB peak gain. The filter rolls off at 6dB per octave (20dB per decade). Iconic rolloff behavior honestly.
The filter accepts the following options:
frequency,fโ sets the filter's central frequency. Default is3000.csgโ constant skirt gain if set to1. Defaults to0.width_type,tโ sets the method to specify the band-width of the filter.hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specifies the band-width of a filter inwidth_typeunits.mix,mโ how much to use the filtered signal in the output. Default is1. Range is between0and1.channels,cโ specifies which channels to filter; by default all available are filtered.normalize,nโ normalize biquad coefficients, by default it's disabled. Enabling it will normalize the magnitude response at DC to0dB.transform,aโ sets the transform type of the IIR filter.didiitditdiilattsvfzdf
precision,rโ sets the precision of filtering.autoโ pick automatic sample format depending on surround filters.s16โ always use signed 16-bit.s32โ always use signed 32-bit.f32โ always use float 32-bit.f64โ always use float 64-bit.
block_size,bโ sets the block size used for reverse IIR processing. If this value is set to a high enough value (higher than the impulse response length truncated when it reaches near zero values), filtering will become linear phase; otherwise, if it's not big enough, it will just produce nasty artifacts. ๐ Note that the filter delay will be exactly this many samples when set to a non-zero value.
Commands ๐ฌ
This filter supports the following commands:
frequency,fโ change bandpass frequency. Syntax for the command is :"frequency".width_type,tโ change bandpasswidth_type. Syntax for the command is :"width_type".width,wโ change bandpass width. Syntax for the command is :"width".mix,mโ change bandpass mix. Syntax for the command is :"mix".
bandreject ๐
Applies a two-pole Butterworth band-reject filter with central frequency frequency, and (3dB-point) band-width width. The filter rolls off at 6dB per octave (20dB per decade). Same math, opposite attitude โ she rejects. ๐
The filter accepts the following options:
frequency,fโ sets the filter's central frequency. Default is3000.width_type,tโ sets the method to specify the band-width of the filter.hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specifies the band-width of a filter inwidth_typeunits.mix,mโ how much to use the filtered signal in the output. Default is1. Range is between0and1.channels,cโ specifies which channels to filter; by default all available are filtered.normalize,nโ normalize biquad coefficients, by default it's disabled. Enabling it will normalize the magnitude response at DC to0dB.transform,aโ sets the transform type of the IIR filter.didiitditdiilattsvfzdf
precision,rโ sets the precision of filtering.autoโ picks the automatic sample format for you, depending on the surround filters โจs16โ always signed 16-bit, no caps32โ always signed 32-bitf32โ always float 32-bitf64โ always float 64-bitblock_size,bโ sets the block size used for reverse IIR processing ๐ง if you set this high enough (higher than the impulse response length truncated when it reaches near-zero values) the filtering goes linear phase โ otherwise, if it's not big enough, you just get nasty artifacts, and nobody wants that ๐
Heads up bestie: the filter delay will be exactly this many samples whenever you set it to a non-zero value. Like, exactly. ๐
Commands
This filter supports the following commands, periodt:
frequency,fโ change the bandreject frequency. Syntax for the command is:"frequency"width_type,tโ change the bandreject width_type. Syntax:"width_type"width,wโ change the bandreject width. Syntax:"width"mix,mโ change the bandreject mix. Syntax:"mix"
bass, lowshelf
Boosts or cuts the bass (lower) frequencies of your audio using a two-pole shelving filter, with a response similar to a standard hi-fi's tone controls ๐๏ธ It's also known as shelving equalisation (EQ), iykyk.
The filter accepts the following options:
gain,gโ gives the gain at 0 Hz. Useful range is about-20(big cut) to+20(big boost) ๐
Beware of clipping when you're using a positive gain, bestie. That's a jump scare you don't want. ๐ญ
frequency,fโ sets the filter's central frequency, so you can extend or reduce the frequency range being boosted or cut. Default value is100 Hz.width_type,tโ sets the method for specifying the band-width of the filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ determines how steep the filter's shelf transition is.poles,pโ sets the number of poles. Default is2.mix,mโ how much of the filtered signal goes in the output. Default is1. Range is between0and1.channels,cโ specify which channels to filter. By default all available channels get filtered.normalize,nโ normalizes biquad coefficients. By default it's disabled. Enabling it will normalize the magnitude response at DC to0dB.transform,aโ sets the transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ sets the precision of filtering:autoโ pick automatic sample format depending on surround filterss16โ always use signed 16-bits32โ always use signed 32-bitf32โ always use float 32-bitf64โ always use float 64-bit
block_size,bโ sets the block size used for reverse IIR processing. If this value is set high enough (higher than the impulse response length truncated when it reaches near-zero values) the filtering will become linear phase; otherwise, if it's not big enough, it'll just produce nasty artifacts ๐
Again for the people in the back: the filter delay will be exactly this many samples when set to a non-zero value.
Commands
This filter supports the following commands:
frequency,fโ change the bass frequency. Syntax for the command is:"frequency"width_type,tโ change the bass width_type. Syntax:"width_type"width,wโ change the bass width. Syntax:"width"gain,gโ change the bass gain. Syntax:"gain"mix,mโ change the bass mix. Syntax:"mix"
biquad
Applies a biquad IIR filter with the coefficients you give it ๐ฆ Where b0, b1, b2 and a0, a1, a2 are the numerator and denominator coefficients respectively. And channels, c specify which channels to filter โ by default, all available channels get filtered.
Commands
This filter supports the following commands:
a0a1a2b0b1b2โ change the biquad parameter. Syntax for the command is:"value"
And also:
mix,mโ how much of the filtered signal goes in the output. Default is1. Range is between0and1.channels,cโ specify which channels to filter. By default all available are filtered.normalize,nโ normalize biquad coefficients โ by default it's disabled. Enabling it normalizes the magnitude response at DC to0dB.transform,aโ set the transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ set the precision of filtering:autoโ pick automatic sample format depending on surround filterss16โ always use signed 16-bits32โ always use signed 32-bitf32โ always use float 32-bitf64โ always use float 64-bit
block_size,bโ set the block size used for reverse IIR processing. Set it high enough (higher than the impulse response length truncated when it reaches near-zero values) and the filtering becomes linear phase; if it's not big enough you get nasty artifacts instead ๐
And yeah โ the filter delay will be exactly this many samples when set to a non-zero value.
bs2b
Bauer stereo to binaural transformation, which lowkey makes listening to stereo audio records on headphones way better ๐ง
To enable compilation of this filter you need to configure FFmpeg with --enable-libbs2b.
It accepts the following parameters:
profileโ pre-defined crossfeed level:defaultโ default level (fcut=700,feed=50)cmoyโ Chu Moy circuit (fcut=700,feed=60)jmeierโ Jan Meier circuit (fcut=650,feed=95)
fcutโ cut frequency (in Hz)feedโ feed level (in Hz)
channelmap
Remaps input channels to new locations, iconic behaviour honestly ๐
It accepts the following parameters:
mapโ maps channels from input to output. The argument is a'|'-separated list of mappings, each in thein_channel-out_channelorin_channelform.in_channelcan be either the name of the input channel (e.g.FLfor front left) or its index in the input channel layout.out_channelis the name of the output channel or its index in the output channel layout. Ifout_channelisn't given, then it's implicitly an index, starting with zero and increasing by one for each mapping. Mixing different types of mappings is not allowed and will result in a parse error ๐ซchannel_layoutโ the channel layout of the output stream. If it's not specified, the filter will guess it based on theout_channelnames or the number of mappings.
Guessed layouts will not necessarily contain channels in the order of the mappings, bestie. Just so you know. ๐
If no mapping is present, the filter implicitly maps input channels to output channels, preserving indices.
Examples
- So for example, assuming a 5.1+downmix input MOV file:
ffmpeg -i in.mov -filter 'channelmap=map=DL-FL|DR-FR' out.wav
will create an output WAV file tagged as stereo from the downmix channels of the input โจ
- To fix a 5.1 WAV improperly encoded in AAC's native channel order:
ffmpeg -i in.wav -filter 'channelmap=1|2|0|5|3|4:5.1' out.wav
channelsplit
Splits each channel from an input audio stream into its own separate output stream ๐
It accepts the following parameters:
channel_layoutโ the channel layout of the input stream. Default is"stereo".channelsโ a channel layout describing the channels to be extracted as separate output streams, or"all"to extract each input channel as a separate stream. Default is"all".
Choosing channels that aren't present in the channel layout of the input will result in an error. No cap. ๐
Examples
- For example, assuming a stereo input MP3 file:
ffmpeg -i in.mp3 -filter_complex channelsplit out.mkv
will create an output Matroska file with two audio streams โ one containing only the left channel and the other the right channel ๐
- Split a 5.1 WAV file into per-channel files:
ffmpeg -i in.wav -filter_complex
'channelsplit=channel_layout=5.1[FL][FR][FC][LFE][SL][SR]'
-map '[FL]' front_left.wav -map '[FR]' front_right.wav -map '[FC]'
front_center.wav -map '[LFE]' lfe.wav -map '[SL]' side_left.wav -map '[SR]'
side_right.wav
- Extract only LFE from a 5.1 WAV file:
ffmpeg -i in.wav -filter_complex 'channelsplit=channel_layout=5.1:channels=LFE[LFE]'
-map '[LFE]' lfe.wav
chorus
Adds a chorus effect to the audio ๐ฆ Can make a single vocal sound like a whole chorus, but you can also throw it on instrumentation.
Chorus is like an echo effect with a short delay, but where echo's delay is constant, chorus's delay is varied using sinusoidal or triangular modulation. The modulation depth defines the range the modulated delay is played before or after the delay. So the delayed sound will sound slower or faster โ like the delayed sound is tuned around the original one, exactly like a chorus where some vocals are slightly off key ๐ค
It accepts the following parameters:
in_gainโ set the input gain. Default is0.4.out_gainโ set the output gain. Default is0.4.delaysโ set the delays. A typical delay is around40msto60ms.decaysโ set the decays.speedsโ set the speeds.depthsโ set the depths.
Examples
- A single delay:
chorus=0.7:0.9:55:0.4:0.25:2
- Two delays:
chorus=0.6:0.9:50|60:0.4|0.32:0.25|0.4:2|1.3
- Fuller sounding chorus with three delays:
chorus=0.5:0.9:50|60|40:0.4|0.32|0.3:0.25|0.4|0.3:2|2.3|1.3
compand
Compresses or expands the audio's dynamic range, which is genuinely so useful ๐ซถ
It accepts the following parameters:
attacksdecays
These are a list of times in seconds, per channel, over which the instantaneous level of the input signal is averaged to determine its volume. attacks refers to an increase in volume and decays refers to a decrease in volume. For most situations the attack time (the response to audio getting louder) should be shorter than the decay time, because the human ear is more sensitive to sudden loud audio than sudden soft audio. A typical value for attack is 0.3 seconds and a typical value for decay is 0.8 seconds. If the number of attacks & decays you specify is lower than the number of channels, the last set attack/decay will be used for all remaining channels ๐
pointsโ the actual transfer function, given as a list of points in dB relative to the max possible signal amplitude. Every key-point list follows this syntax:"x0/y0|x1/y1|x2/y2|...."or"x0/y0 x1/y1 x2/y2 ...."โ yes bestie, either the pipe or the space, both slay.
The input values must be in strictly increasing order, but the transfer function does not have to rise monotonically. The point "0/0" is assumed by default but you can override it (with "0/out-dBn"). Typical values for the transfer function are "-70/-70|-60/-20|1/0".
soft-kneeโ sets the curve radius in dB for all joints. Defaults to0.01.gainโ extra gain in dB applied at every point on the transfer function, so you can tweak the overall gain without rewriting the whole curve. Defaults to0.volumeโ an initial volume in dB assumed for each channel when filtering starts. This lets you supply a nominal level up front so that, for example, a huge gain isn't slammed onto the initial signal levels before the companding has even started doing its thing. For audio that's initially quiet, a typical value is-90dB. Defaults to0.delayโ a delay in seconds. The input audio gets analyzed immediately, but the audio itself is delayed before it's fed to the volume adjuster. Pick a delay roughly equal to the attack/decay times and the filter gets to operate in predictive mode instead of reactive mode. Defaults to0. ๐
โจ Examples โจ
- Make music with both quiet and loud passages, suitable for listening in a noisy environment:
compand=.3|.3:1|1:-90/-60|-60/-40|-40/-30|-20/-20:6:0:-90:0.2
Another example, this one for audio with whisper parts and explosion parts:
compand=0|0:1|1:-90/-900|-70/-70|-30/-9|0/-3:6:0:0:0
- A noise gate for when the noise is at a lower level than the signal:
compand=.1|.1:.2|.2:-900/-900|-50.1/-900|-50/-50:.01:0:-90:.1
- Here's another noise gate, this time for when the noise is at a higher level than the signal (which makes it, in some ways, similar to squelch):
compand=.1|.1:.1|.1:-45.1/-45.1|-45/-900|0/-900:.01:45:-90:.1
- 2:1 compression starting at -6dB:
compand=points=-80/-80|-6/-6|0/-3.8|20/3.5
- 2:1 compression starting at -9dB:
compand=points=-80/-80|-9/-9|0/-5.3|20/2.9
- 2:1 compression starting at -12dB:
compand=points=-80/-80|-12/-12|0/-6.8|20/1.9
- 2:1 compression starting at -18dB:
compand=points=-80/-80|-18/-18|0/-9.8|20/0.7
- 3:1 compression starting at -15dB:
compand=points=-80/-80|-15/-15|0/-10.8|20/-5.2
- Compressor/Gate:
compand=points=-80/-105|-62/-80|-15.4/-15.4|0/-12|20/-7.6
- Expander:
compand=attacks=0:points=-80/-169|-54/-80|-49.5/-64.6|-41.1/-41.1|-25.8/-15|-10.8/-4.5|0/0|20/8.3
- Hard limiter at -6dB:
compand=attacks=0:points=-80/-80|-6/-6|20/-6
- Hard limiter at -12dB:
compand=attacks=0:points=-80/-80|-12/-12|20/-12
- Hard noise gate at -35 dB:
compand=attacks=0:points=-80/-115|-35.1/-80|-35/-35|20/20
- Soft limiter:
compand=attacks=0:points=-80/-80|-12.4/-12.4|-6/-8|0/-6.8|20/-2.8
๐ compensationdelay ๐
The Compensation Delay Line is a metric-based delay โ its whole personality is compensating for microphones or speakers sitting in different positions.
Picture it: you recorded guitar with two mics placed in different spots. Because the front of a sound wave has a fixed speed under normal conditions, the phasing of the mics can vary depending on where they are and how they're positioned relative to each other. The best mix happens when those mics are in phase (synchronized). And heads up โ a distance of ~30 cm between mics makes one mic capture the signal in antiphase to the other, which makes the final mix sound moody. ๐ญ This filter fixes phasing problems by adding different delays to each mic track and syncing them up.
You get the best result when you take one track as your base and synchronize the other tracks to it one by one. Also remember that the synchronization/delay tolerance depends on the sample rate too โ higher sample rates give you more tolerance. โจ
The filter accepts these parameters:
mmโ set the distance in millimeters. This is compensation distance for fine tuning. Default is0.cmโ set the distance in cm. This is compensation distance for tightening up the distance setup. Default is0.mโ set the distance in meters. This is compensation distance for hard distance setup. Default is0.dryโ set the dry amount, aka how much unprocessed (dry) signal you want. Default is0.wetโ set the wet amount, aka how much processed (wet) signal you want. Default is1.tempโ set the temperature in degrees Celsius. This is the temperature of the environment. Default is20.
Commands
This filter supports all of the above options as commands. ๐
๐ฆ crossfeed ๐ฆ
Applies a headphone crossfeed filter.
Crossfeed is the process of blending the left and right channels of a stereo audio recording. It's mainly used to reduce the extreme stereo separation of low frequencies.
The whole intent? Produce a more speaker-like sound for the listener. ๐ง
The filter accepts these options:
strengthโ set the strength of the crossfeed. Default is0.2. Allowed range is from0to1. This sets the gain of the low shelf filter for the side part of the stereo image. Default is-6dB. Max allowed is-30db when strength is set to1.rangeโ set the soundstage wideness. Default is0.5. Allowed range is from0to1. This sets the cut off frequency of the low shelf filter. Default cut off is near1550Hz. With range set to1, the cut off frequency is set to2100Hz.slopeโ set the curve slope of the low shelf filter. Default is0.5. Allowed range is from0.01to1.level_inโ set the input gain. Default is0.9.level_outโ set the output gain. Default is1.block_sizeโ set the block size used for reverse IIR processing. Set this to a high enough value (higher than the impulse response length truncated when it reaches near-zero values) and the filtering becomes linear phase โ otherwise, if it's not big enough, it'll just produce nasty artifacts. ๐
Note that the filter delay will be exactly this many samples when set to a non-zero value.
Commands
This filter supports all of the above options as commands.
๐ธ crystalizer ๐ธ
A simple algorithm for audio noise sharpening.
This filter linearly increases the differences between each audio sample.
The filter accepts these options:
iโ sets the intensity of the effect (default:2.0). Must be in range between-10.0to0(unchanged sound) to10.0(maximum effect). Want inverse filtering? Use a negative value.cโ enable clipping. Enabled by default.
Commands
This filter supports all of the above options as commands.
โญ dcshift โญ
Applies a DC shift to the audio.
Super useful for removing a DC offset (which could be, like, a hardware problem in your recording chain) from the audio. The effect of a DC offset is reduced headroom, and therefore reduced volume. Pro tip: the astats filter can tell you if a signal has a DC offset. ๐
shiftโ set the DC shift. Allowed range is[-1, 1]. It says how much to shift the audio by.limitergainโ optional. It should have a value much less than1(e.g.0.05or0.02) and it's used to prevent clipping.
๐ deesser ๐
Applies de-essing to the audio samples. Bye bye, harsh ssss sounds.
iโ set the intensity for triggering de-essing. Allowed range is from0to1. Default is0.mโ set the amount of ducking on the treble part of the sound. Allowed range is from0to1. Default is0.5.fโ how much of the original frequency content to keep when de-essing. Allowed range is from0to1. Default is0.5.sโ set the output mode.
It accepts these values:
iโ pass input unchanged.oโ pass ess filtered out.eโ pass only ess.
Default value is o.
๐ dialoguenhance ๐**
Enhances dialogue in stereo audio.
This filter takes stereo input and produces surround (3.0) channel output. The newly produced front center channel carries enhanced speech dialogue that was originally available in both stereo channels. The front left and front right channels come out the same as they were in the stereo input. ๐ฌ
The filter accepts these options:
originalโ set the original center factor to keep in the front center channel output. Allowed range is from0to1. Default value is1.enhanceโ set the dialogue enhance factor to put in the front center channel output. Allowed range is from0to3. Default value is1.voiceโ set the voice detection factor. Allowed range is from2to32. Default value is2.
Commands
This filter supports all of the above options as commands.
๐ drmeter ๐
Measures audio dynamic range.
For reference: DR values of 14 and higher show up in very dynamic material. DR of 8 to 13 shows up in transition material. And anything less than 8 has very poor dynamics and is very compressed. ๐
The filter accepts this option:
lengthโ set the window length in seconds used to split audio into segments of equal length. Default is3seconds.
๐ dynaudnorm ๐
Dynamic Audio Normalizer. Say hi to the main character of normalization. โจ
This filter applies a certain amount of gain to the input audio in order to bring its peak magnitude up to a target level (e.g. 0 dBFS). But โ unlike more "simple" normalization algorithms โ the Dynamic Audio Normalizer dynamically re-adjusts the gain factor to the input audio. That means it can apply extra gain to the "quiet" sections of the audio while avoiding distortions or clipping the "loud" sections. In other words: the Dynamic Audio Normalizer "evens out" the volume of quiet and loud sections, in the sense that the volume of each section gets brought to the same target level. Note, though, that it pulls this off without applying "dynamic range compressing" โ it retains 100% of the dynamic range within each section of the audio file. ๐ฅ
framelen, f
Sets the frame length in milliseconds โ range is 10 to 8000 milliseconds, default is 500 milliseconds. ๐
Okay so here's the tea on why frames even exist: the Dynamic Audio Normalizer chews through your input audio in little chunks called frames. Why? Because a peak magnitude is literally meaningless for a single lonely sample value ๐ญ โ you have to look at a contiguous sequence of samples to figure out the peak. A "standard" normalizer would just grab the peak of the whole entire file, but our girl here determines the peak magnitude individually for each frame, one at a time, no cap. ๐ธ
You spec the frame length in milliseconds, and the default 500 has been found to give good results with most files (it just works, iykyk). Heads up though: the exact frame length in number of samples gets determined automatically, based on the sampling rate of each individual input audio file. โจ
gausssize, g
Sets the Gaussian filter window size. Range 3 to 301, and it must be an odd number. Default is 31. ๐ซถ
Honestly? This is probably the most important parameter of the whole Dynamic Audio Normalizer โ it's the "window size" of the Gaussian smoothing filter. The window is specified in frames, centered around the current frame, and for simplicity's sake it has to be odd. So the default 31 takes into account the current frame, plus the 15 frames before it and the 15 frames after it. Bestie math. ๐ง
- Bigger window โ stronger smoothing effect โ less gain variation โ slower gain adaptation
- Smaller window โ weaker smoothing effect โ more gain variation โ faster gain adaptation
In other words: the more you crank this value up, the more the Dynamic Audio Normalizer starts acting like a "traditional" normalization filter. Flip it around and the more you decrease it, the more she behaves like a dynamic range compressor. Choose your fighter. ๐
peak, p
Sets the target peak value โ the highest permissible magnitude level for the normalized audio input. ๐
The filter will try to approach that target peak magnitude as closely as possible, but at the same time it makes sure the normalized signal will never exceed the peak magnitude. A frame's maximum local gain factor is imposed directly by the target peak magnitude. Default value is 0.95, which leaves a headroom of 5%*. ๐
It is not recommended to go above this value. Respect the headroom, bestie.
maxgain, m
Sets the maximum gain factor. Range 1.0 to 100.0, default 10.0. ๐ฅ
The Dynamic Audio Normalizer works out the maximum possible (local) gain factor for each input frame โ meaning the biggest gain factor that won't cause clipping or distortion. That number is determined by the frame's highest magnitude sample. But she also bounds each frame's maximum gain factor by a predetermined (global) maximum gain factor, specifically so we don't get unhinged gain factors in "silent" or almost-silent frames. ๐
Default 10.0 is enough for most inputs, and it's usually not recommended to raise it. That said, if your input has an extremely low overall volume level, you might need to allow higher gain factors. ๐
Important caveat though: this is not a simple "hard" threshold (i.e. it doesn't just cut off values above the threshold). Instead a "sigmoid" threshold function is applied, so the gain factors smoothly approach the threshold value and never exceed it. Smooth like butter. ๐ฆ
targetrms, r
Sets the target RMS. Range 0.0 to 1.0. Default is 0.0 โ disabled. ๐
By default, the Dynamic Audio Normalizer does "peak" normalization, meaning the maximum local gain factor for each frame is defined (only) by that frame's highest magnitude sample. That way the samples can be amplified as much as possible without exceeding the maximum signal level โ i.e. without clipping. โจ
Optionally, though, she can also take into account the frame's root mean square, abbreviated RMS. In electrical engineering, RMS is commonly used to determine the power of a time-varying signal, and it's therefore considered a better approximation of "perceived loudness" than just looking at the signal's peak magnitude. So by adjusting all frames to a constant RMS value, you can establish a uniform "perceived loudness." ๐ง
If you specify a target RMS value, a frame's local gain factor becomes the factor that would result in exactly that RMS value. Note, however, that the maximum local gain factor is still restricted by the frame's highest magnitude sample, in order to prevent clipping. Safety first. ๐ซถ
coupling, n
Turn on channels coupling โ and yes, it's enabled by default. ๐ธ
By default the Dynamic Audio Normalizer amplifies all channels by the same amount, meaning the same gain factor gets applied to every channel, so the maximum possible gain factor is determined by the "loudest" channel. Main character channel energy. ๐
But sometimes recordings have uneven volume across channels โ e.g. one channel might be "quieter" than the other one(s). In that case you can use this option to disable channel coupling. Then the gain factor is determined independently for each channel, depending only on that individual channel's highest magnitude sample. Which is lowkey perfect for harmonizing the volume of the different channels. ๐
correctdc, c
Turns on DC bias correction โ disabled by default. ๐ฆ
So an audio signal (in the time domain) is a sequence of sample values, and in the Dynamic Audio Normalizer those values are represented in the -1.0 to 1.0 range, regardless of the original input format. Normally the audio signal, or "waveform", should be centered around the zero point. Meaning: if we calculate the mean value of all samples in a file, or in a single frame, the result should be 0.0 or at least very close to it. โญ
If there's a significant deviation of the mean value from 0.0, in either the positive or negative direction, that's called a DC bias or DC offset. And since a DC bias is clearly undesirable, this filter provides optional DC bias correction. With it enabled, the Dynamic Audio Normalizer determines the mean value (the "DC correction" offset) of each input frame and subtracts that value from all of the frame's sample values, which makes sure those samples are centered around 0.0 again. ๐
Also, to avoid "gaps" at the frame boundaries, the DC correction offset values get interpolated smoothly between neighbouring frames. No awkward seams. โจ
altboundary, b
Turns on alternative boundary mode โ disabled by default. ๐ง
The Dynamic Audio Normalizer takes into account a certain neighbourhood around each frame: the preceding frames and the subsequent frames. But for the "boundary" frames sitting at the very beginning and the very end of the audio file, not all neighbouring frames are available. Specifically, for the first few frames the preceding frames aren't known, and for the last few frames the subsequent frames aren't known. ๐ญ
So the question is: which gain factors should we assume for the missing frames in that "boundary" region? She implements two modes to deal with this. The default boundary mode assumes a gain factor of exactly 1.0 for the missing frames, resulting in a smooth "fade in" and "fade out" at the beginning and end of the input, respectively. ๐ซ
compress, s
Sets the compress factor. Range 0.0 to 30.0, default 0.0. ๐ฅ
By default, the Dynamic Audio Normalizer does not apply "traditional" compression โ signal peaks won't be pruned, so the full dynamic range is retained within each local neighbourhood. But sometimes you do want to combine her normalization algorithm with a more "traditional" compression, and that's exactly what this optional compression (thresholding) function is for. ๐
If (and only if) the compression feature is enabled, all input frames get processed by a soft knee thresholding function prior to the actual normalization process. Put simply: the thresholding function prunes all samples whose magnitude exceeds a certain threshold value. But she doesn't just slap a fixed threshold on there โ the threshold value gets adjusted for each individual frame. ๐
In general, smaller parameters result in stronger compression, and vice versa. And values below 3.0 are not recommended, because audible distortion may appear. You've been warned bestie. ๐
threshold, t
Sets the target threshold value โ the lowest permissible magnitude level for the audio input that will actually get normalized. ๐
If an input frame's volume is above this value, the frame will be normalized. Otherwise, the frame may not be normalized at all. Default is 0, which means all input frames get normalized. This option is mostly useful when you don't want digital noise getting amplified. ๐
channels, h
Specify which channels to filter. By default, all available channels get filtered. ๐
overlap, o
Specify overlap for frames. If set to 0 (the default), no frame overlapping is done. ๐ฆ
Using values >0 and <1 will make less conservative gain adjustments โ like when the framelen option is set to a smaller value. And if the framelen option value is compensated for non-zero overlap, then the gain adjustments will be smoother across time compared to the zero overlap case. Smooth queen. โจ
curve, v
Specify the peak mapping curve expression, which is going to be used when calculating the gain applied to frames. The max output frame gain will still be limited by the other options mentioned previously for this filter. ๐
The expression can contain the following constants:
chโ current channel numbersnโ current sample numbernb_channelsโ number of channelstโ timestamp expressed in secondssrโ sample ratepโ current frame peak value ๐ธ
๐ฌ Commands
This filter supports the all above options as commands. yep, all of them, go wild โจ
๐ง earwax
Makes audio easier to listen to on headphones. literally what it says on the tin ๐ซถ
This filter adds `cues' to 44.1kHz stereo (i.e. audio CD format) audio so that when listened to on headphones the stereo image is moved from inside your head (standard for headphones) to outside and in front of the listener (standard for speakers). think main character energy but for your ears ๐
Ported from SoX.
๐ equalizer
Apply a two-pole peaking equalisation (EQ) filter. With this filter, the signal-level at and around a selected frequency can be increased or decreased, whilst (unlike bandpass and bandreject filters) that at all other frequencies is unchanged. it's giving "surgical glow-up for one frequency band" ๐
In order to produce complex equalisation curves, this filter can be given several times, each with a different central frequency. stack 'em, bestie ๐
The filter accepts the following options:
frequency,fโ Set the filter's central frequency in Hz.width_type,tโ Set method to specify band-width of filter.hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ Specify the band-width of a filter in width_type units.gain,gโ Set the required gain or attenuation in dB. Beware of clipping when using a positive gain. โ ๏ธ fr fr, watch that ceilingmix,mโ How much to use filtered signal in output. Default is 1. Range is between 0 and 1.channels,cโ Specify which channels to filter, by default all available are filtered.normalize,nโ Normalize biquad coefficients, by default is disabled. Enabling it will normalize magnitude response at DC to 0dB.transform,aโ Set transform type of IIR filter.didiitditdiilattsvfzdf
precision,rโ Set precision of filtering.autoโ Pick automatic sample format depending on surround filters.s16โ Always use signed 16-bit.s32โ Always use signed 32-bit.f32โ Always use float 32-bit.f64โ Always use float 64-bit.
block_size,bโ Set block size used for reverse IIR processing. If this value is set to high enough value (higher than impulse response length truncated when reaches near zero values) filtering will become linear phase otherwise if not big enough it will just produce nasty artifacts. ๐ญ
Note that filter delay will be exactly this many samples when set to non-zero value.
โจ Examples
- Attenuate 10 dB at 1000 Hz, with a bandwidth of 200 Hz:
equalizer=f=1000:t=h:width=200:g=-10
- Apply 2 dB gain at 1000 Hz with Q 1 and attenuate 5 dB at 100 Hz with Q 2:
equalizer=f=1000:t=q:w=1:g=2,equalizer=f=100:t=q:w=2:g=-5
๐ฌ Commands
This filter supports the following commands:
frequency,fโ Change equalizer frequency. Syntax for the command is : "frequency"width_type,tโ Change equalizer width_type. Syntax for the command is : "width_type"width,wโ Change equalizer width. Syntax for the command is : "width"gain,gโ Change equalizer gain. Syntax for the command is : "gain"mix,mโ Change equalizer mix. Syntax for the command is : "mix"
๐ฅ extrastereo
Linearly increases the difference between left and right channels which adds some sort of "live" effect to playback. hi-fi girlies stay winning ๐
The filter accepts the following options:
mโ Sets the difference coefficient (default: 2.5). 0.0 means mono sound (average of both channels), with 1.0 sound will be unchanged, with -1.0 left and right channels will be swapped. channels doing a whole swap arc ๐ญcโ Enable clipping. By default is enabled.
๐ฌ Commands
This filter supports the all above options as commands.
๐ฆ firequalizer
Apply FIR Equalization using arbitrary frequency response. the way this filter just does whatever curve you dream up ๐
The filter accepts the following option:
gainโ Set gain curve equation (in dB). The expression can contain variables:fโ the evaluated frequencysrโ sample ratechโ channel number, set to 0 when multichannels evaluation is disabledchidโ channel id, seelibavutil/channel_layout.h, set to the first channel id when multichannels evaluation is disabledchsโ number of channelschlayoutโ channel_layout, seelibavutil/channel_layout.h
and functions:
gain_interpolate(f)โ interpolate gain on frequency f based on gain_entrycubic_interpolate(f)โ same as gain_interpolate, but smoother
This option is also available as command. Default is gain_interpolate(f).
gain_entryโ Set gain entry forgain_interpolatefunction. The expression can contain functions:entry(f, g)โ store gain entry at frequency f with value g
This option is also available as command.
delayโ Set filter delay in seconds. Higher value means more accurate. Default is 0.01.accuracyโ Set filter accuracy in Hz. Lower value means more accurate. Default is 5.wfuncโ Set window function. Acceptable values are:rectangularโ rectangular window, useful when gain curve is already smoothhannโ hann window (default)hammingโ hamming windowblackmanโ blackman windownuttall3โ 3-terms continuous 1st derivative nuttall windowmnuttall3โ minimum 3-terms discontinuous nuttall windownuttallโ 4-terms continuous 1st derivative nuttall windowbnuttallโ minimum 4-terms discontinuous nuttall (blackman-nuttall) windowbharrisโ blackman-harris windowtukeyโ tukey window
fixedโ If enabled, use fixed number of audio samples. This improves speed when filtering with large delay. Default is disabled.multiโ Enable multichannels evaluation on gain. Default is disabled.zero_phaseโ Enable zero phase mode by subtracting timestamp to compensate delay. Default is disabled.scaleโ Set scale used by gain. Acceptable values are:linlinโ linear frequency, linear gainlinlogโ linear frequency, logarithmic (in dB) gain (default)loglinโ logarithmic (in octave scale where 20 Hz is 0) frequency, linear gainloglogโ logarithmic frequency, logarithmic gain
dumpfileโ Set file for dumping, suitable for gnuplot.dumpscaleโ Set scale for dumpfile. Acceptable values are same withscaleoption. Default islinlog.fft2โ Enable 2-channel convolution using complex FFT. This improves speed significantly. Default is disabled.min_phaseโ Enable minimum phase impulse response. Default is disabled.
โจ Examples
- lowpass at 1000 Hz:
firequalizer=gain='if(lt(f,1000), 0, -INF)'
- lowpass at 1000 Hz with
gain_entry:
firequalizer=gain_entry='entry(1000,0); entry(1001, -INF)'
- custom equalization:
firequalizer=gain_entry='entry(100,0); entry(400, -4); entry(1000, -6); entry(2000, 0)'
- higher delay with zero phase to compensate delay:
firequalizer=delay=0.1:fixed=on:zero_phase=on
- lowpass on left channel, highpass on right channel:
firequalizer=gain='if(eq(chid,1), gain_interpolate(f), if(eq(chid,2), gain_interpolate(1e6+f), 0))'
:gain_entry='entry(1000, 0); entry(1001,-INF); entry(1e6+1000,0)':multi=on
๐ flanger
Apply a flanging effect to the audio. that classic whoosh, iconic behavior ๐ซ
The filter accepts the following options:
delayโ Set base delay in milliseconds. Range from 0 to 30. Default value is 0.depthโ Set added sweep delay in milliseconds. Range from 0 to 10. Default value is 2.regenโ Set percentage regeneration (delayed signal feedback). Range from -95 to 95. Default value is 0.widthโ Set percentage of delayed signal mixed with original. Range from 0 to 100. Default value is 71.speedโ Set sweeps per second (Hz). Range from 0.1 to 10. Default value is 0.5.shapeโ Set swept wave shape, can betriangularorsinusoidal. Default value issinusoidal.phaseโ Set swept wave percentage-shift for multi channel. Range from 0 to 100. Default value is 25.interpโ Set delay-line interpolation,linearorquadratic. Default islinear.
๐ง haas
Apply Haas effect to audio.
Note that this makes most sense to apply on mono signals. With this filter applied to mono signals it give some directionality and stretches its stereo image. mono girlies, this one's for you ๐ซถ
The filter accepts the following options:
level_inโ Set input level. By default is 1, or 0dBlevel_outโ Set output level. By default is 1, or 0dB.side_gainโ Set gain applied to side part of signal. By default is 1.middle_sourceโ Set kind of middle source. Can be one of the following:leftโ Pick left channel.rightโ Pick right channel.midโ Pick middle part signal of stereo image.sideโ Pick side part signal of stereo image.
middle_phaseโ Change middle phase. By default is disabled.left_delayโ Set left channel delay. By default is 2.05 milliseconds.left_balanceโ Set left channel balance. By default is -1.left_gainโ Set left channel gain. By default is 1.left_phaseโ Change left phase. By default is disabled.right_delayโ Set right channel delay. By defaults is 2.12 milliseconds.right_balanceโ Set right channel balance. By default is 1.right_gainโ Set right channel gain. By default is 1.right_phaseโ Change right phase. By default is enabled.
๐ hdcd
Decodes High Definition Compatible Digital (HDCD) data. A 16-bit PCM stream with embedded HDCD codes is expanded into a 20-bit PCM stream. glow-up, but make it bit depth โจ
The filter supports the Peak Extend and Low-level Gain Adjustment features of HDCD, and detects the Transient Filter flag.
ffmpeg -i HDCD16.flac -af hdcd OUT24.flac
When using the filter with wav, note the default encoding for wav is 16-bit, so the resulting 20-bit stream will be truncated back to 16-bit. Use something like -acodec pcm_s24le after the filter to get 24-bit PCM output. don't let wav snatch your bits ๐ญ
ffmpeg -i HDCD16.wav -af hdcd OUT16.wav
ffmpeg -i HDCD16.wav -af hdcd -c:a pcm_s24le OUT24.wav
The filter accepts the following options:
disable_autoconvertโ Disable any automatic format conversion or resampling in the filter graph.
ngl if you skip this one you might get converted on without even knowing ๐
process_stereoโ deals with the stereo channels together, as a unit. Iftarget_gaindoesn't match between the two channels, the filter treats that as invalid and just keeps the last validtarget_gaininstead. bestie behaviour honestly, it's not gonna trust a mismatched value ๐cdt_msโ sets the code detect timer period, in ms. that's it, that's the whole thing โจforce_peโ always extend peaks above-3dBFS, even whenPEisn't signaled. like, pushing the peak extend through regardless ๐analyze_modeโ replaces the audio with a solid tone and adjusts its amplitude to signal some specific part of the decoding process. the output file can be loaded in an audio editor next to the original to help with analysis. literally a visualisation hack and it ate ๐ฅ
"analyze_mode=pe:force_pe=true" can be used to see all samples above the PE level ๐
the modes are:
0,offโ Disabled.1,lleโ Gain adjustment level at each sample.2,peโ Samples where peak extend occurs.3,cdtโ Samples where the code detect timer is active.4,tgmโ Samples where the target gain does not match between channels.
๐ง headphone ๐ง
okay so this one applies head-related transfer functions (HRTFs) to build virtual loudspeakers around the listener, for binaural listening via headphones โ it's giving "surround sound but make it your earbuds" โจ the HRIRs come in via additional streams, and for each channel you need one stereo input stream ๐
the filter accepts the following options:
mapโ sets the mapping of input streams for the convolution. the argument is a'|'-separated list of channel names, in the order they're given as additional stream inputs for the filter. this also specifies the number of input streams. number of input streams must be not less than number of channels in the first stream plus one. no cap.gainโ sets the gain applied to audio. value is in dB. default is0.typeโ sets the processing type. can betimeorfreq.timeprocesses audio in the time domain, which is slow ๐ขfreqprocesses audio in the frequency domain, which is fast โก default isfreq. slay.lfeโ sets a custom gain for LFE channels. value is in dB. default is0.sizeโ sets the size of the frame, in number of samples, processed at once. default value is1024. allowed range is from1024to96000. periodt.hrirโ sets the format of the hrir stream. default value isstereo. alternative value ismultich. if it's set tostereo, the number of additional streams should be greater than or equal to the number of input channels in the first input stream โ and each additional stream should have a stereo number of channels ๐ if it's set tomultich, the number of additional streams should be exactly one, and the number of input channels of that additional stream should be equal to or greater than twice the number of channels of the first input stream. iykyk.
Examples
- Full example using wav files as coefficients with amovie filters for a 7.1 downmix โ each amovie filter uses a stereo file with IR coefficients as input. the files give coefficients for each position of the virtual loudspeaker ๐
ffmpeg -i input.wav
-filter_complex "amovie=azi_270_ele_0_DFC.wav[sr];amovie=azi_90_ele_0_DFC.wav[sl];amovie=azi_225_ele_0_DFC.wav[br];amovie=azi_135_ele_0_DFC.wav[bl];amovie=azi_0_ele_0_DFC.wav,asplit[fc][lfe];amovie=azi_35_ele_0_DFC.wav[fl];amovie=azi_325_ele_0_DFC.wav[fr];[0:a][fl][fr][fc][lfe][bl][br][sl][sr]headphone=FL|FR|FC|LFE|BL|BR|SL|SR"
output.wav
- Full example using wav files as coefficients with amovie filters for a 7.1 downmix, but now in
multichhrir format ๐
ffmpeg -i input.wav -filter_complex "amovie=minp.wav[hrirs];[0:a][hrirs]headphone=map=FL|FR|FC|LFE|BL|BR|SL|SR:hrir=multich"
output.wav
highpass ๐ฆ
applies a high-pass filter with a 3dB point frequency. the filter can be single-pole, or double-pole (that's the default). the filter rolls off at 6dB per pole per octave (20dB per pole per decade). iconic behaviour, honestly ๐ธ
the filter accepts the following options:
frequency,fโ sets the frequency in Hz. default is3000.poles,pโ sets the number of poles. default is2.width_type,tโ sets the method used to specify the band-width of the filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specifies the band-width of a filter, inwidth_typeunits. applies only to double-pole filters. the default is0.707qand gives a Butterworth response ๐mix,mโ how much of the filtered signal to use in the output. default is1. range is between0and1.channels,cโ specifies which channels to filter โ by default, all available channels are filtered.normalize,nโ normalizes the biquad coefficients, disabled by default. enabling it will normalize the magnitude response at DC to0dB.transform,aโ sets the transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ sets the precision of filtering:autoโ pick the automatic sample format depending on the surround filters.s16โ always use signed 16-bit.s32โ always use signed 32-bit.f32โ always use float 32-bit.f64โ always use float 64-bit.
block_size,bโ sets the block size used for reverse IIR processing. if this value is high enough (higher than the impulse response length, truncated when it reaches near-zero values), the filtering becomes linear phase โ otherwise, if it isn't big enough, it'll just produce nasty artifacts ๐ note that the filter delay will be exactly this many samples when set to a non-zero value. no cap, that's literally the warning.
Commands ๐ซถ
this filter supports the following commands:
frequency,fโ change the highpass frequency. syntax for the command is:"frequency"width_type,tโ change the highpasswidth_type. syntax for the command is:"width_type"width,wโ change the highpass width. syntax for the command is:"width"mix,mโ change the highpass mix. syntax for the command is:"mix"
join ๐
joins multiple input streams into one multi-channel stream. it accepts the following parameters:
inputsโ the number of input streams. defaults to2.channel_layoutโ the desired output channel layout. defaults tostereo.mapโ maps channels from the inputs to the output. the argument is a'|'-separated list of mappings, each in the"input_idx.in_channel-out_channel"form.input_idxis the 0-based index of the input stream.in_channelcan be either the name of the input channel (e.g.FLfor front left) or its index in the specified input stream.out_channelis the name of the output channel ๐
the filter will attempt to guess the mappings when they're not specified explicitly โ it does so by first trying to find an unused matching input channel, and if that fails, it picks the first unused input channel. bestie is doing her best with the info she has ๐
join 3 inputs (with properly set channel layouts):
ffmpeg -i INPUT1 -i INPUT2 -i INPUT3 -filter_complex join=inputs=3 OUTPUT
build a 5.1 output from 6 single-channel streams:
ffmpeg -i fl -i fr -i fc -i sl -i sr -i lfe -filter_complex
'join=inputs=6:channel_layout=5.1:map=0.0-FL|1.0-FR|2.0-FC|3.0-SL|4.0-SR|5.0-LFE'
out
ladspa ๐ง
loads a LADSPA (Linux Audio Developer's Simple Plugin API) plugin. the way this one opens up a whole plugin ecosystem, obsessed ๐
to enable compilation of this filter you need to configure FFmpeg with "--enable-ladspa" โญ
file,fโ specifies the name of the LADSPA plugin library to load. if the environment variableLADSPA_PATHis defined, the LADSPA plugin is searched in each one of the directories specified by the colon-separated list inLADSPA_PATH; otherwise it's searched in the standard LADSPA paths, which are, in this order:HOME/.ladspa/lib/,/usr/local/lib/ladspa/,/usr/lib/ladspa/.plugin,pโ specifies the plugin within the library. some libraries contain only one plugin, but others contain many of them. if this isn't set, the filter will list all available plugins within the specified library.controls,cโ sets the'|'-separated list of controls, which are zero or more floating point values that determine the behavior of the loaded plugin (for example delay, threshold or gain). controls need to be defined using the following syntax:c0=value0|c1=value1|c2=value2|..., wherevalueiis the value set on the i-th control. alternatively they can also be defined using this syntax:value0|value1|value2|..., wherevalueiis the value set on the i-th control. ifcontrolsis set to"help", all available controls and their valid ranges are printed ๐sample_rate,sโ specifies the sample rate, default44100. only used if the plugin has zero inputs.nb_samples,nโ sets the number of samples per channel per output frame, default is1024. only used if the plugin has zero inputs.duration,dโ sets the minimum duration of the sourced audio. see the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. note that the resulting duration may be longer than the specified duration, because the generated audio is always cut at the end of a complete frame โ๏ธ if it's not specified, or the expressed duration is negative, the audio is supposed to be generated forever. only used if the plugin has zero inputs.latency,lโ enables latency compensation, disabled by default. only used if the plugin has inputs.
Examples ๐
- List all available plugins within the amp (LADSPA example plugin) library:
ladspa=file=amp
- List all available controls and their valid ranges for the
"vcf_notch"plugin from the"VCF"library:
ladspa=f=vcf:p=vcf_notch:c=help
- Simulate low quality audio equipment using the
"Computer Music Toolkit"(CMT) plugin library:
ladspa=file=cmt:plugin=lofi:controls=c0=22|c1=12|c2=12
- Add reverberation to the audio using TAP-plugins (Tom's Audio Processing plugins):
ladspa=file=tap_reverb:tap_reverb
- Generate white noise, with
0.2amplitude:
ladspa=file=cmt:noise_source_white:c=c0=.2
- Generate 20 bpm clicks using the plugin
"C* Click - Metronome"from the"C* Audio Plugin Suite"(CAPS) library:
ladspa=file=caps:Click:c=c1=20'
- Apply the
"C* Eq10X2 - Stereo 10-band equaliser"effect:
ladspa=caps:Eq10X2:c=c0=-48|c9=-24|c3=12|c4=2
- Increase volume by 20dB using the fast lookahead limiter from Steve Harris'
"SWH Plugins"collection:
ladspa=fast_lookahead_limiter_1913:fastLookaheadLimiter:20|0|2
- Attenuate low frequencies using the Multiband EQ from Steve Harris'
"SWH Plugins"collection:
ladspa=mbeq_1197:mbeq:-24|-24|-24|0|0|0|0|0|0|0|0|0|0|0|0
- Reduce the stereo image using
"Narrower"from the"C* Audio Plugin Suite"(CAPS) library: ladspa=caps:Narrowerโจ- Okay so next up, ANOTHER white noise moment โ this time repping the "C* Audio Plugin Suite" (CAPS) library:
ladspa=caps:White:.2
- And some fractal noise, also from CAPS, because we're fancy like that:
ladspa=caps:Fractal:c=c1=1
- Dynamic volume normalization via the "VLevel" plugin โ chef's kiss for making quiet bits audible without blowing up the loud bits:
ladspa=vlevel-ladspa:vlevel_mono
๐ธ Commands ๐ธ
This filter is a chatty one, it takes commands:
cNโ modify the N-th control value. ๐ And if the value you pass isn't valid? Bestie, it's just ignored and the previous one stays. No drama, no crash.
๐ loudnorm ๐
EBU R128 loudness normalization, and it's giving main character energy in the audio world. It does both dynamic and linear normalization modes, and it supports both single pass (livestreams, files) and double pass (files) modes. This algorithm can target IL, LRA, and maximum true peak. In dynamic mode, to accurately detect true peaks, the audio stream will be upsampled to 192 kHz โ so use the -ar option or the aresample filter to explicitly set an output sample rate. ๐ฆ
It accepts these options:
I,iโ set integrated loudness target. Range is-70.0โ-5.0. Default value is-24.0.LRA,lraโ set loudness range target. Range is1.0โ50.0. Default value is7.0.TP,tpโ set maximum true peak. Range is-9.0โ+0.0. Default value is-2.0.measured_I,measured_iโ measured IL of the input file. Range is-99.0โ+0.0.measured_LRA,measured_lraโ measured LRA of the input file. Range is0.0โ99.0.measured_TP,measured_tpโ measured true peak of the input file. Range is-99.0โ+99.0.measured_threshโ measured threshold of the input file. Range is-99.0โ+0.0.offsetโ set offset gain. The gain is applied before the true-peak limiter. Range is-99.0โ+99.0. Default is+0.0.linearโ normalize by linearly scaling the source audio. For this,measured_I,measured_LRA,measured_TP, andmeasured_threshmust all be specified. Target LRA shouldn't be lower than source LRA, and the change in integrated loudness shouldn't result in a true peak which exceeds the target TP. If any of these conditions aren't met, normalization mode will revert to dynamic. Options aretrueorfalse. Default istrue.dual_monoโ treat mono input files as "dual-mono". If a mono file is intended for playback on a stereo system, its EBU R128 measurement will be perceptually incorrect, and this option compensates for that effect when set totrue. Multi-channel input files are not affected by this option. Options aretrueorfalse. Default isfalse. ๐print_formatโ set print format for stats. Options aresummary,json, ornone. Default value isnone.stats_fileโ write stats to the specified file. The format is controlled byprint_format, which must be set. Specify-to write to standard output. Default is unset. โญ
๐ lowpass ๐
Apply a low-pass filter with 3dB point frequency. The filter can be either single-pole or double-pole (that's the default, bestie). The filter rolls off at 6dB per pole per octave (20dB per pole per decade). Lowkey iconic.
It accepts these options:
frequency,fโ set frequency in Hz. Default is500.poles,pโ set number of poles. Default is2.width_type,tโ set the method used to specify the band-width of the filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specify the band-width of the filter inwidth_typeunits. Applies only to the double-pole filter. The default is0.707qand gives a Butterworth response. ๐mix,mโ how much of the filtered signal to use in the output. Default is1. Range is between0and1.channels,cโ specify which channels to filter; by default all available channels are filtered.normalize,nโ normalize biquad coefficients; by default this is disabled. Enabling it will normalize the magnitude response at DC to0dB.transform,aโ set the transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ set the precision of filtering:autoโ pick the automatic sample format depending on surround filters.s16โ always use signed 16-bit.s32โ always use signed 32-bit.f32โ always use float 32-bit.f64โ always use float 64-bit.
block_size,bโ set the block size used for reverse IIR processing. If this value is set high enough (higher than the impulse response length truncated when it reaches near-zero values), filtering will become linear phase โ otherwise, if it's not big enough, it will just produce nasty artifacts. ๐ญ
Heads up: the filter delay will be exactly this many samples when set to a non-zero value. No cap.
๐ Examples ๐
- Lowpass only the LFE channel โ and if LFE isn't present, it does nothing:
lowpass=c=LFE
๐ธ Commands ๐ธ
This filter supports these commands:
frequency,fโ change the lowpass frequency. Syntax for the command is:frequencywidth_type,tโ change the lowpass width_type. Syntax for the command is:width_typewidth,wโ change the lowpass width. Syntax for the command is:widthmix,mโ change the lowpass mix. Syntax for the command is:mix
๐ฆ lv2 ๐ฆ
Load an LV2 (LADSPA Version 2) plugin. Plugin girlies rise.
To enable compilation of this filter you need to configure FFmpeg with --enable-lv2.
plugin,pโ specifies the plugin URI. You may need to escape':'. ๐controls,cโ set the'|'-separated list of controls, which are zero or more floating point values that determine the behavior of the loaded plugin (for example delay, threshold or gain). Ifcontrolsis set tohelp, all available controls and their valid ranges are printed. Super handy.sample_rate,sโ specify the sample rate, default is44100. Only used if the plugin has zero inputs.nb_samples,nโ set the number of samples per channel per each output frame, default is1024. Only used if the plugin has zero inputs.duration,dโ set the minimum duration of the sourced audio. See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. Note that the resulting duration may be greater than the specified duration, since the generated audio is always cut at the end of a complete frame. If not specified, or the expressed duration is negative, the audio is supposed to be generated forever. Only used if the plugin has zero inputs. โญ
๐ Examples ๐
- Apply the bass enhancer plugin from Calf:
lv2=p=http\\\\://calf.sourceforge.net/plugins/BassEnhancer:c=amount=2
- Apply the vinyl plugin from Calf โ yes, the crackle is on purpose, that's the vibe:
lv2=p=http\\\\://calf.sourceforge.net/plugins/Vinyl:c=drone=0.2|aging=0.5
- Apply the bit crusher plugin from ArtyFX:
lv2=p=http\\\\://www.openavproductions.com/artyfx#bitta:c=crush=0.3
๐ธ Commands ๐ธ
This filter supports all options that are exported by the plugin as commands. Slay.
๐ฅ mcompand ๐ฅ
Multiband compress or expand the audio's dynamic range. It's giving loudness warpaint.
The input audio is divided into bands using 4th order Linkwitz-Riley IIRs. This is akin to the crossover of a loudspeaker, and results in a flat frequency response when there's no compander action happening.
It accepts this parameter:
argsโ the option syntax is:attack,decay,[attack,decay..] soft-knee points crossover_frequency [delay [initial_volume [gain]]] | attack,decay .... For an explanation of each item, refer to thecompandfilter documentation. ๐
๐ pan ๐
Mix channels with specific gain levels. The filter accepts the output channel layout followed by a set of channel definitions.
This filter is also designed to efficiently remap the channels of an audio stream โ so like, it's not just a mixer, it's also a glow-up artist for your channel layout. โจ
The filter accepts parameters of the form: l|outdef|outdef|...
lโ output channel layout or number of channels.outdefโ output channel specification, of the form:out_name=[gain*]in_name[(+-)[gain*]in_name...]out_nameโ output channel to define, either a channel name (FL,FR, etc.) or a channel number (c0,c1, etc.).gainโ multiplicative coefficient for the channel;1leaves the volume unchanged.in_nameโ input channel to use, seeout_namefor details. It is not possible to mix named and numbered input channels. ๐ซถ
If the = in a channel specification is replaced by <, then the gains for that specification will be renormalized so that the total is 1, thus avoiding clipping noise. Big brain move.
๐ Mixing examples ๐
For example, if you want to down-mix from stereo to mono, but with a bigger factor for the left channel:
pan=1c|c0=0.9*c0+0.1*c1
A customized down-mix to stereo that works automatically for 3-, 4-, 5- and 7-channels surround:
pan=stereo| FL < FL + 0.5*FC + 0.6*BL + 0.6*SL | FR < FR + 0.5*FC + 0.6*BR + 0.6*SR
Note thatffmpegintegrates a default down-mix (and up-mix) system that should be preferred (see the-acoption) unless you have very specific needs. Like, don't do this manually if you don't have to, bestie.
๐ฆ Remapping examples ๐ฆ
The channel remapping will be effective if, and only if:
- gain coefficients are zeroes or ones,
- only one input per channel output.
If all these conditions are satisfied, the filter will notify the user (Pure channel mapping detected), and use an optimized and lossless method to do the remapping. Literally the best case scenario.
For example, if you have a 5.1 source and want a stereo audio stream by dropping the extra channels:
pan="stereo| c0=FL | c1=FR"
Given the same source, you can also switch front left and front right channels and keep the input channel layout:
pan="5.1| c0=c1 | c1=c0 | c2=c2 | c3=c3 | c4=c4 | c5=c5"
If the input is a stereo audio stream, you can mute the front left channel (and still keep the stereo channel layout) with:
pan="stereo|c1=c1"
Still with a stereo audio stream input, you can copy the right channel into both front left and right:
pan="stereo| c0=FR | c1=FR"
๐ replaygain ๐
ReplayGain scanner filter. This filter takes an audio stream as input and outputs it unchanged โ like, it's just here to observe and judge, no notes. At the end of filtering it displays track_gain and track_peak.
It accepts these exported read-only options:
track_gainโ exported track gain in dB at end of stream.track_peakโ exported track peak at end of stream.
๐ง resample ๐ง
Convert the audio sample format, sample rate and channel layout. It is not meant to be used directly. Like, this is backstage crew, not the main character โ let the other filters call it.
๐ rubberband ๐
Apply time-stretching and pitch-shifting with librubberband. Stretchy, pitchy, iconic.
To enable compilation of this filter, you need to configure FFmpeg with --enable-librubberband.
The filter accepts these options:
tempoโ sets the tempo scale factor ๐๏ธ (how fast the vibes go).pitchโ sets the pitch scale factor, so you can yeet the key up or down ๐ .transientsโ picks the transients detector. The possible values are literally:crispmixedsmooth
detectorโ picks the detector. Possible values:compoundpercussivesoft
phaseโ sets the phase. Possible values:laminarindependent
windowโ sets the processing window size. Possible values:standardshortlong
smoothingโ sets smoothing. Possible values:offon
formantโ enables formant preservation when shift pitching ๐ค. Possible values:shiftedpreserved
pitchqโ sets pitch quality. Possible values:qualityspeedconsistency
channelsโ sets channels. Possible values:aparttogether
Commands
This filter supports the following commands, bestie โ you can poke it live while it's running ๐:
tempoโ change the filter tempo scale factor. Syntax for the command is :"tempo"pitchโ change the filter pitch scale factor. Syntax for the command is :"pitch"
๐๏ธ sidechaincompress
Okay so this one is genuinely iconic โจ โ it acts like a normal compressor but it has the ability to compress the detected signal using a second input signal. It needs two input streams and returns one output stream. The first input stream gets processed depending on the second stream's signal. The filtered signal can then be filtered with other filters in later stages of processing. Go look at pan and amerge filter, iykyk ๐ซถ.
The filter accepts the following options:
level_inโ set input gain. Default is1. Range is between0.015625and64.modeโ set the mode of compressor operation. Can be"upward"or"downward". Default is"downward".thresholdโ if a signal of the second stream raises above this level it will affect the gain reduction of the first stream. By default is0.125. Range is between0.00097563and1.ratioโ set a ratio about which the signal is reduced.1:2means that if the level raised 4dB above the threshold, it will be only 2dB above after the reduction. Default is2. Range is between1and20.attackโ amount of milliseconds the signal has to rise above the threshold before gain reduction starts. Default is20. Range is between0.01and2000.releaseโ amount of milliseconds the signal has to fall below the threshold before reduction is decreased again. Default is250. Range is between0.01and9000.makeupโ set the amount by how much signal will be amplified after processing. Default is1. Range is from1to64.kneeโ curve the sharp knee around the threshold to enter gain reduction more softly ๐ธ. Default is2.82843. Range is between1and8.linkโ choose if the"average"level between all channels of the side-chain stream or the louder ("maximum") channel of the side-chain stream affects the reduction. Default is"average".detectionโ should the exact signal be taken in case of"peak"or an RMS one in case of"rms". Default is"rms"which is mainly smoother.level_scโ set sidechain gain. Default is1. Range is between0.015625and64.mixโ how much to use the compressed signal in output. Default is1. Range is between0and1.
Commands
This filter supports all the above options as commands ๐ (yes, all of them, go off).
Examples
- Full ffmpeg example taking 2 audio inputs, 1st input to be compressed depending on the signal of 2nd input and later compressed signal to be merged with 2nd input:
ffmpeg -i main.flac -i sidechain.flac -filter_complex "[1:a]asplit=2[sc][mix];[0:a][sc]sidechaincompress[compr];[compr][mix]amerge"
๐ช sidechaingate
A sidechain gate acts like a normal (wideband) gate but it has the ability to filter the detected signal before sending it to the gain reduction stage. Normally a gate uses the full range signal to detect a level above the threshold. For example: if you cut all lower frequencies from your sidechain signal, the gate will decrease the volume of your track only if not enough highs appear. With this technique you are able to reduce the resonation of a natural drum or remove "rumbling" of muted strokes from a heavily distorted guitar ๐ธ๐ฅ. It needs two input streams and returns one output stream. First input stream will be processed depending on the second stream's signal.
The filter accepts the following options:
level_inโ set input level before filtering. Default is1. Allowed range is from0.015625to64.modeโ set the mode of operation. Can be"upward"or"downward". Default is"downward". If set to"upward"mode, higher parts of the signal will be amplified, expanding dynamic range in the upward direction. Otherwise, in the case of"downward", lower parts of the signal will be reduced.rangeโ set the level of gain reduction when the signal is below the threshold. Default is0.06125. Allowed range is from0to1. Setting this to0disables reduction and then the filter behaves like an expander ๐.thresholdโ if a signal rises above this level the gain reduction is released. Default is0.125. Allowed range is from0to1.ratioโ set a ratio about which the signal is reduced. Default is2. Allowed range is from1to9000.attackโ amount of milliseconds the signal has to rise above the threshold before gain reduction stops. Default is20milliseconds. Allowed range is from0.01to9000.releaseโ amount of milliseconds the signal has to fall below the threshold before the reduction is increased again. Default is250milliseconds. Allowed range is from0.01to9000.makeupโ set amount of amplification of signal after processing. Default is1. Allowed range is from1to64.kneeโ curve the sharp knee around the threshold to enter gain reduction more softly. Default is2.828427125. Allowed range is from1to8.detectionโ choose if the exact signal should be taken for detection or an RMS-like one. Default isrms. Can bepeakorrms.linkโ choose if the average level between all channels or the louder channel affects the reduction. Default isaverage. Can beaverageormaximum.level_scโ set sidechain gain. Default is1. Range is from0.015625to64.
Commands
This filter supports all the above options as commands ๐ซถ.
๐คซ silencedetect
Detects silence in an audio stream. Like, it literally clocks the quiet parts for you ๐.
This filter logs a message when it detects that the input audio volume is less than or equal to a noise tolerance value for a duration greater than or equal to the minimum detected noise duration.
The printed times and duration are expressed in seconds. The "lavfi.silence_start" or "lavfi.silence_start.X" metadata key is set on the first frame whose timestamp equals or exceeds the detection duration, and it contains the timestamp of the first frame of the silence.
The "lavfi.silence_duration" or "lavfi.silence_duration.X" and "lavfi.silence_end" or "lavfi.silence_end.X" metadata keys are set on the first frame after the silence. If mono is enabled, and each channel is evaluated separately, the ".X" suffixed keys are used, and X corresponds to the channel number ๐.
The filter accepts the following options:
noise,nโ set noise tolerance. Can be specified in dB (in case"dB"is appended to the specified value) or amplitude ratio. Default is-60dB, or0.001.duration,dโ set silence duration until notification (default is2seconds). See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax.mono,mโ process each channel separately, instead of combined. By default is disabled.
Examples
- Detect 5 seconds of silence with
-50dBnoise tolerance:
silencedetect=n=-50dB:d=5
- Complete example with ffmpeg to detect silence with
0.0001noise tolerance insilence.mp3:
ffmpeg -i silence.mp3 -af silencedetect=noise=0.0001 -f null -
โ๏ธ silenceremove
Remove silence from the beginning, middle or end of the audio. The glow-up potential is unreal, ngl ๐.
The filter accepts the following options:
start_periodsโ this value is used to indicate if audio should be trimmed at the beginning of the audio. A value of zero indicates no silence should be trimmed from the beginning. When specifying a non-zero value, it trims audio up until it finds non-silence. Normally, when trimming silence from the beginning of audio thestart_periodswill be1, but it can be increased to higher values to trim all audio up to a specific count of non-silence periods. Default value is0.start_durationโ specify the amount of time that non-silence must be detected before it stops trimming audio. By increasing the duration, bursts of noise can be treated as silence and trimmed off. Default value is0.start_thresholdโ this indicates what sample value should be treated as silence. For digital audio, a value of0may be fine, but for audio recorded from analog, you may wish to increase the value to account for background noise. Can be specified in dB (in case"dB"is appended to the specified value) or amplitude ratio. Default value is0.start_silenceโ specify max duration of silence at the beginning that will be kept after trimming. Default is0, which is equal to trimming all samples detected as silence.start_modeโ specify the mode of detection of silence end at the start of multi-channel audio. Can beanyorall. Default isany. Withany, any sample from any channel that is detected as non-silence will trigger the end of silence trimming at the start of the audio stream. Withall, only if every sample from every channel is detected as non-silence will it trigger the end of silence trimming at the start of the audio stream โ limited usage, fr.stop_periodsโ set the count for trimming silence from the end of audio. When specifying a positive value, it trims audio after it finds the specified silence period. To remove silence from the middle of a file, specify astop_periodsthat is negative. This value is then treated as a positive value and is used to indicate the effect should restart processing as specified bystop_periods, making it suitable for removing periods of silence in the middle of the audio. Default value is0.stop_durationโ specify a duration of silence that must exist before audio is not copied any more. By specifying a higher duration, silence that is wanted can be left in the audio. Default value is0.stop_thresholdโ okay so this is literallystart_threshold's twin sister, except she's the one who trims the silence at the end of your audio instead of the start ๐ . You can give it dB (just slap a"dB"on the end of your value) or an amplitude ratio. Default is0. Slay.stop_silenceโ sets the max duration of silence at the end that gets kept after all the trimming goes down ๐. Default is0, which literally means "trim every single sample we detected as silence", no survivors, periodt.stop_modeโ picks the detection mode for where silence starts, after your multi-channel audio has already begun. Values areanyorall, default isall.anyโ literally any sample from any channel that reads as silence will trigger the start of silence trimming after the audio stream starts. Lowkey limited usage, ngl.allโ only when every sample from every channel is detected as silence does the trimming start after the audio stream starts. Strict queen behavior ๐.
detectionโ tells the filter how to detect silence, bestie:avgโ mean of absolute values of the samples in the moving window.rmsโ root squared mean of absolute values of the samples in the moving window.peakโ maximum of absolute values of the samples in the moving window.medianโ median of absolute values of the samples in the moving window.ptpโ absolute of the max peak to min peak difference of the samples in the moving window.devโ standard deviation of the values of the samples in the moving window.
Default value is rms โจ.
windowโ duration in seconds used to calculate the window size (in samples) for detecting silence. Setting it to0effectively disables all windowing and uses only a single sample per channel for detection โ and in that case you may need to also setstart_silenceand/orstop_silenceto nonzero values andstart_durationand/orstop_durationto nonzero values. Default is0.02, allowed range is0to10. ๐ฆtimestampโ processing mode for every audio frame's output timestamp:writeโ full timestamps rewrite, keeps only the start time for the first output frame.copyโ non-dropped frames keep the same timestamp as the input audio frame.
Default value is "write" ๐.
Examples ๐ธ
- Bestie, this one lets you start a recording that doesn't have that awkward delay at the start โ you know, the gap between pressing record and actually performing:
silenceremove=start_periods=1:start_duration=5:start_threshold=0.02
- Trim all the silence from beginning to end where there's more than 1 second of it:
silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-90dB
- Trim every digital silence sample using
peakdetection, beginning to end, where there's more than 0 samples of digital silence and it's detected in all channels at the same positions in the stream:
silenceremove=window=0:detection=peak:stop_mode=all:start_mode=all:stop_periods=-1:stop_threshold=0
- Trim every 2nd silence period you encounter, beginning to end, where there's more than 1 second of silence per period:
silenceremove=stop_periods=-2:stop_duration=1:stop_threshold=-90dB
- Same vibe as above but keep a maximum of 0.5 seconds of silence from each trimmed period:
silenceremove=stop_periods=-2:stop_duration=1:stop_threshold=-90dB:stop_silence=0.5
- Same as above again, but keep a maximum of 1.5 seconds of silence from the start of the audio:
silenceremove=stop_periods=-2:stop_duration=1:stop_threshold=-90dB:stop_silence=0.5:start_periods=1:start_duration=1:start_silence=1.5:stop_threshold=-90dB
Commands ๐
This filter supports some of the above options as commands. Periodt.
sofalizer ๐ง
SOFAlizer uses head-related transfer functions (HRTFs) to build virtual loudspeakers around the listener so you get binaural listening through headphones โ and yes, audio formats up to 9 channels are supported ๐. The HRTFs live in SOFA files (there's a whole database at <http://www.sofacoustics.org/>). SOFAlizer is developed at the Acoustics Research Institute (ARI) of the Austrian Academy of Sciences. Iconic institution behavior, honestly.
To enable compilation of this filter you need to configure FFmpeg with --enable-libmysofa โญ
The filter accepts these options:
sofaโ set the SOFA file used for rendering.gainโ set the gain applied to audio. Value is in dB. Default is0.rotationโ set the rotation of the virtual loudspeakers in deg. Default is0.elevationโ set the elevation of the virtual speakers in deg. Default is0.radiusโ set the distance in meters between the loudspeakers and the listener, using near-field HRTFs. Default is1.typeโ set the processing type. Values aretimeorfreq.timeprocesses audio in the time domain, which is slow ๐.freqprocesses audio in the frequency domain, which is fast โก. Default isfreq.speakersโ set custom positions of the virtual loudspeakers. The syntax is:<CH> <AZIM> <ELEV>[|<CH> <AZIM> <ELEV>|...]. Each virtual loudspeaker is described by a short channel name followed by azimuth and elevation in degrees, and each description is separated by'|'. For example, to override the front left and front right channel positions use:'speakers=FL 45 15|FR 345 15'. Descriptions with unrecognised channel names are just ignored, no drama ๐ .lfegainโ set a custom gain for LFE channels. Value is in dB. Default is0.framesizeโ set a custom frame size in number of samples. Default is1024. Allowed range is from1024to96000. Only used if thetypeoption is set tofreq.normalizeโ should all IRs be normalized when importing the SOFA file? By default this is enabled.interpolateโ should the nearest IRs be interpolated with neighbor IRs if the exact position doesn't match? By default this is disabled.minphaseโ minphase all IRs when loading the SOFA file. By default this is disabled.anglestepโ set the neighbor search angle step. Only used if theinterpolateoption is enabled.radstepโ set the neighbor search radius step. Only used if theinterpolateoption is enabled.
Examples ๐
- Using the
ClubFritz6sofa file:
sofalizer=sofa=/path/to/ClubFritz6.sofa:type=freq:radius=1
- Using the
ClubFritz12sofa file with a bigger radius and a small rotation:
sofalizer=sofa=/path/to/ClubFritz12.sofa:type=freq:radius=2:rotation=5
- Similar to above but with custom speaker positions for front left, front right, back left and back right, plus a custom gain:
"sofalizer=sofa=/path/to/ClubFritz6.sofa:type=freq:radius=2:speakers=FL 45|FR 315|BL 135|BR 225:gain=28"
speechnorm ๐ฃ๏ธ
Speech Normalizer. It's giving audio glow-up โจ
This filter expands or compresses each half-cycle of audio samples โ that's a local set of samples all above zero or all below zero, sitting between the two nearest zero crossings โ depending on the threshold value, so the audio reaches the target peak value under the conditions controlled by the options below.
It accepts these options:
peak,pโ set the expansion target peak value. This specifies the highest allowed absolute amplitude level for the normalized audio input. Default is0.95, allowed range is0.0to1.0.expansion,eโ set the maximum expansion factor. Allowed range is1.0to50.0, default is2.0. This option controls the maximum local half-cycle expansion of samples. The max expansion would be such that the local peak value reaches the target peak value but never surpasses it, and the ratio between the new and previous peak value does not surpass this option's value. Highkey important, ngl.compression,cโ set the maximum compression factor. Allowed range is1.0to50.0, default is2.0. This controls the maximum local half-cycle compression of samples. It's only used if thethresholdoption is set to a value greater than0.0โ in those cases, when the local peak is lower than or the same as the value set bythreshold, all samples belonging to that peak's half-cycle get compressed by the current compression factor.threshold,tโ set the threshold value. Default is0.0, allowed range is0.0to1.0. This specifies which half-cycles get compressed and which get expanded: any half-cycle whose local peak value is below or the same as this value gets compressed by the current compression factor; otherwise, if it's greater than the threshold value, it gets expanded with the expansion factor so it could reach the peak target value โ but never surpass it ๐.raise,rโ set the expansion raising amount per each half-cycle of samples. Default is0.001, allowed range is0.0to1.0. This controls how fast the expansion factor is raised per each new half-cycle until it reaches theexpansionvalue.
Setting this one too high may lead to distortions ๐ญ careful bestie.
fall,fโ set the compression raising amount per each half-cycle of samples. Default is0.001, allowed range is0.0to1.0. This controls how fast the compression factor is raised per each new half-cycle until it reaches thecompressionvalue.channels,hโ specify which channels to filter. By default all available channels are filtered.invert,iโ enable inverted filtering, disabled by default. This flips the interpretation of thethresholdoption: when enabled, any half-cycle of samples whose local peak value is below or the same as thethresholdoption gets expanded, otherwise it gets compressed ๐.link,lโ link channels when calculating the gain applied to each filtered channel sample, disabled by default. When disabled, each filtered channel's gain calculation is independent; when enabled, the minimum of all possible gains for each filtered channel is used ๐ซถ.rms,mโ set the expansion target RMS value. This specifies the highest allowed RMS level for the normalized audio input. Default is0.0, which means disabled. Allowed range is0.0to1.0.
Commands ๐
This filter supports all the above options as commands. All of them. Obsessed.
Examples โญ
- Weak and slow amplification:
speechnorm=e=3:r=0.00001:l=1
- Moderate and slow amplification:
speechnorm=e=6.25:r=0.00001:l=1
- Strong and fast amplification:
speechnorm=e=12.5:r=0.0001:l=1
- Very strong and fast amplification:
speechnorm=e=25:r=0.0001:l=1
- Extreme and fast amplification:
speechnorm=e=50:r=0.0001:l=1
stereotools ๐
Okay bestie, this one is the stereo swiss-army knife โ it's got all the handy little utilities for managing stereo signals, like converting M/S stereo recordings to L/R while keeping full control over the parameters, or spreading the stereo image of your master track. Iconic behaviour honestly.
The filter accepts the following options:
level_inโ sets the input level before filtering, for both channels. Default is1. Allowed range is from0.015625to64.level_outโ sets the output level after filtering, for both channels. Default is1. Allowed range is from0.015625to64.balance_inโ input balance between both channels. Default is0. Allowed range is from-1to1.balance_outโ output balance between both channels. Default is0. Allowed range is from-1to1.softclipโ enables softclipping, which gives you analog distortion instead of that harsh digital 0dB clipping. Disabled by default.mutelโ mutes the left channel. Disabled by default.muterโ mutes the right channel. Disabled by default.phaselโ flips the phase of the left channel. Disabled by default.phaserโ flips the phase of the right channel. Disabled by default.modeโ sets the stereo mode. Available values are:lr>lrโ Left/Right to Left/Right, this is the default, no notes.lr>msโ Left/Right to Mid/Side.ms>lrโ Mid/Side to Left/Right.lr>llโ Left/Right to Left/Left.lr>rrโ Left/Right to Right/Right.lr>l+rโ Left/Right to Left + Right.lr>rlโ Left/Right to Right/Left.ms>llโ Mid/Side to Left/Left.ms>rrโ Mid/Side to Right/Right.ms>rlโ Mid/Side to Right/Left.lr>l-rโ Left/Right to Left - Right.
slevโ sets the level of the side signal. Default is1. Allowed range is from0.015625to64.sbalโ sets the balance of the side signal. Default is0. Allowed range is from-1to1.mlevโ sets the level of the middle signal. Default is1. Allowed range is from0.015625to64.mpanโ sets the middle signal pan. Default is0. Allowed range is from-1to1.baseโ sets the stereo base between mono and inversed channels. Default is0. Allowed range is from-1to1.delayโ sets the delay in milliseconds, i.e. how much to delay the left from the right channel and vice versa. Default is0. Allowed range is from-20to20.sclevelโ sets the S/C level. Default is1. Allowed range is from1to100.phaseโ sets the stereo phase in degrees. Default is0. Allowed range is from0to360.bmode_in,bmode_outโ set the balance mode for thebalance_in/balance_outoption. Can be one of the following:balanceโ classic balance mode. Attenuates one channel at a time. Gain is raised up to1.amplitudeโ similar to the classic mode above, but gain is raised up to2.powerโ equal power distribution, from-6dBto+6dBrange.
Commands ๐ฌ
This filter supports all of the above options as commands. Slay.
Examples โจ
- Apply a karaoke-like effect:
stereotools=mlev=0.015625
- Convert an M/S signal to L/R:
"stereotools=mode=ms>lr"
stereowiden ๐ฆ
This filter enhances the stereo effect by suppressing the signal that's common to both channels, and by delaying the signal of the left into the right and vice versa โ thereby widening the stereo effect. It's giving "bigger than your headphones," fr fr.
The filter accepts the following options:
delayโ time in milliseconds of the delay of the left signal into the right and vice versa. Default is20milliseconds.feedbackโ amount of gain in the delayed signal into the right and vice versa. This gives a delay effect of the left signal in the right output and vice versa, which gives the widening effect. Default is0.3.crossfeedโ cross feed of the left into the right with inverted phase. This helps suppress the mono. If the value is1it will cancel all the signal common to both channels. Default is0.3.drymixโ sets the level of the input signal of the original channel. Default is0.8.
Commands ๐ฌ
This filter supports all of the above options except delay as commands. (Not delay, bestie โ don't @ me.)
superequalizer ๐
Applies an 18 band equalizer. Eighteen. Bands. Obsessed.
The filter accepts the following options:
1bโ set65Hzband gain.2bโ set92Hzband gain.3bโ set131Hzband gain.4bโ set185Hzband gain.5bโ set262Hzband gain.6bโ set370Hzband gain.7bโ set523Hzband gain.8bโ set740Hzband gain.9bโ set1047Hzband gain.10bโ set1480Hzband gain.11bโ set2093Hzband gain.12bโ set2960Hzband gain.13bโ set4186Hzband gain.14bโ set5920Hzband gain.15bโ set8372Hzband gain.16bโ set11840Hzband gain.17bโ set16744Hzband gain.18bโ set20000Hzband gain.
surround ๐
Applies the audio surround upmix filter. This filter lets you produce multichannel output from an audio stream โ mono-ish in, full cinematic situation out. Main character energy.
The filter accepts the following options:
chl_outโ sets the output channel layout. By default, this is5.1. See the Channel Layout section in theffmpeg-utils(1)manual for the required syntax.chl_inโ sets the input channel layout. By default, this isstereo. See the Channel Layout section in theffmpeg-utils(1)manual for the required syntax.level_inโ sets the input volume level. By default, this is1.level_outโ sets the output volume level. By default, this is1.lfeโ enable LFE channel output if the output channel layout has it. By default, this is enabled.lfe_lowโ sets the LFE low cut off frequency. By default, this is128 Hz.lfe_highโ sets the LFE high cut off frequency. By default, this is256 Hz.lfe_modeโ sets the LFE mode, can beaddorsub. Default isadd. Inaddmode, the LFE channel is created from the input audio and added to the output. Insubmode, the LFE channel is created from the input audio and added to the output, but also all non-LFE output channels are subtracted with the output LFE channel.smoothโ sets the temporal smoothness strength, used to gradually change factors when transforming stereo sound in time. Allowed range is from0.0to1.0. Useful for improving output quality withfocusoption values greater than0.0. Default is0.0. Only values inside this range and without edges are effective.angleโ sets the angle of the stereo surround transform. Allowed range is from0to360. Default is90.focusโ sets the focus of the stereo surround transform. Allowed range is from-1to1. Default is0.fc_inโ sets the front center input volume. By default, this is1.fc_outโ sets the front center output volume. By default, this is1.fl_inโ sets the front left input volume. By default, this is1.fl_outโ sets the front left output volume. By default, this is1.fr_inโ sets the front right input volume. By default, this is1.fr_outโ sets the front right output volume. By default, this is1.sl_inโ sets the side left input volume. By default, this is1.sl_outโ sets the side left output volume. By default, this is1.sr_inโ sets the side right input volume. By default, this is1.sr_outโ sets the side right output volume. By default, this is1.bl_inโ sets the back left input volume. By default, this is1.bl_outโ sets the back left output volume. By default, this is1.br_inโ sets the back right input volume. By default, this is1.br_outโ sets the back right output volume. By default, this is1.bc_inโ sets the back center input volume. By default, this is1.bc_outโ sets the back center output volume. By default, this is1.lfe_inโ sets the LFE input volume. By default, this is1.lfe_outโ sets the LFE output volume. By default, this is1.allxโ sets the spread usage of the stereo image across the X axis for all channels. Allowed range is from-1to15. By default this value is negative-1, and thus unused.allyโ sets the spread usage of the stereo image across the Y axis for all channels. Allowed range is from-1to15. By default this value is negative-1, and thus unused.fcx,flx,frx,blx,brx,slx,srx,bcxโ set the spread usage of the stereo image across the X axis for each channel. Allowed range is from0.06to15. By default this value is0.5.fcy,fly,fry,bly,bry,sly,sry,bcyโ set the spread usage of the stereo image across the Y axis for each channel. Allowed range is from0.06to15. By default this value is0.5.win_sizeโ sets the window size. Allowed range is from1024to65536. Default size is4096.win_funcโ sets the window function. It accepts the following values:
rect
bartlett
hann, hanning
hamming
blackman
welch
flattop
bharris
bnuttall
bhann
sine
nuttall
lanczos
gauss
tukey
dolph
cauchy
parzen
poisson
bohman
kaiser
Default is "hann".
overlapโ sets the window overlap. If set to1, the recommended overlap for the selected window function will be picked. Default is0.5.
tiltshelf ๐ธ
Boosts or cuts the lower frequencies and cuts or boosts the higher frequencies of the audio, using a two-pole shelving filter with a response similar to that of a standard hi-fi's tone controls. This is also known as shelving equalisation (EQ). Very much the "vintage warmth" vibe.
The filter accepts the following options:
gain,gโ gives the gain at0 Hz. Its useful range is about-20(for a large cut) to+20(for a large boost). Beware of clipping when using a positive gain. ๐frequency,fโ sets the filter's central frequency, so it can be used to extend or reduce the frequency range to be boosted or cut. The default value is3000 Hz.width_type,tโ sets the method used to specify the band-width of the filter.hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ determines how steep the filter's shelf transition is.poles,pโ sets the number of poles. Default is2.mix,mโ how much of the filtered signal is used in the output. Default is1. Range is between0and1.channels,cโ specifies which channels to filter; by default all available are filtered.normalize,nโ normalizes the biquad coefficients; by default it's disabled. Enabling it will normalize the magnitude response at DC to0dB.transform,aโ sets the transform type of the IIR filter.
di
dii
tdi
tdii
latt
svf
zdf
precision, r โ sets the filtering precision โจ
Pick your sample format energy:
autoโ picks the automatic sample format depending on the surround filters ๐ฆs16โ always use signed 16-bits32โ always use signed 32-bitf32โ always use float 32-bitf64โ always use float 64-bit
block_size, b โ sets the block size used for reverse IIR processing ๐
So here's the tea: if you set this high enough (higher than the impulse response length truncated when it reaches near-zero values), the filtering becomes linear phase. If it's not big enough? It just produces nasty artifacts. No cap, it's giving cursed.
Heads up bestie: the filter delay will be exactly this many samples when set to a non-zero value. Every. Single. Sample. ๐ญ
Commands
This filter supports some options as commands. ๐ซถ
treble, highshelf ๐
Boosts or cuts the treble (upper) frequencies of the audio, using a two-pole shelving filter with a response similar to a standard hi-fi's tone-controls. This is also known as shelving equalisation (EQ). Iconic behavior honestly.
The filter accepts the following options:
gain, g
Gives the gain at whichever is the lower of ~22 kHz and the Nyquist frequency. Its useful range is about -20 (for a large cut) to +20 (for a large boost). โ ๏ธ Beware of clipping when using a positive gain โ she will clip, and she will not apologize.
frequency, f
Sets the filter's central frequency, so you can extend or reduce the frequency range being boosted or cut. Default value is 3000 Hz. ๐
width_type, t
Sets the method for specifying the band-width of the filter:
hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width, w
Determines how steep the filter's shelf transition is. Slay the transition, basically. ๐ฅ
poles, p
Sets the number of poles. Default is 2.
mix, m
How much of the filtered signal goes into the output. Default is 1. Range is between 0 and 1.
channels, c
Specifies which channels to filter. By default all available channels are filtered. ๐
normalize, n
Normalizes the biquad coefficients โ by default this is disabled. Enabling it will normalize the magnitude response at DC to 0dB.
transform, a
Sets the transform type of the IIR filter:
didiitditdiilattsvfzdf
precision, r
Sets the precision of filtering.
autoโ picks the automatic sample format depending on the surround filterss16โ always use signed 16-bits32โ always use signed 32-bitf32โ always use float 32-bitf64โ always use float 64-bit
block_size, b
Sets the block size used for reverse IIR processing. Set it high enough (higher than the impulse response length truncated when it reaches near-zero values) and the filtering will become linear phase; if it's not big enough it will just produce nasty artifacts. ๐ฌ
Note that the filter delay will be exactly this many samples when set to a non-zero value.
Commands
This filter supports the following commands:
frequency,fโ change the treble frequency. Syntax for the command is:"frequency"width_type,tโ change the treble width_type. Syntax for the command is:"width_type"width,wโ change the treble width. Syntax for the command is:"width"gain,gโ change the treble gain. Syntax for the command is:"gain"mix,mโ change the treble mix. Syntax for the command is:"mix"
tremolo ๐
Sinusoidal amplitude modulation. It's giving underwater vibes.
The filter accepts the following options:
fโ modulation frequency in Hertz. Modulation frequencies in the subharmonic range (20 Hz or lower) will result in a tremolo effect. This filter may also be used as a ring modulator by specifying a modulation frequency higher than 20 Hz. Range is0.1-20000.0. Default value is5.0Hz.dโ depth of modulation as a percentage. Range is0.0-1.0. Default value is0.5.
vibrato ๐ฆ
Sinusoidal phase modulation. Tremolo's more mysterious cousin fr fr.
The filter accepts the following options:
fโ modulation frequency in Hertz. Range is0.1-20000.0. Default value is5.0Hz.dโ depth of modulation as a percentage. Range is0.0-1.0. Default value is0.5.
virtualbass ๐
Applies the audio Virtual Bass filter. Bass go brrr.
This filter accepts stereo input and produces stereo with LFE (2.1) channels output. The newly produced LFE channel has enhanced virtual bass originally obtained from both stereo channels. This filter outputs the front left and front right channels unchanged as available in the stereo input. Main character energy: keeps the originals, adds a whole new icon. ๐
The filter accepts the following options:
cutoffโ sets the virtual bass cutoff frequency. Default value is250Hz. Allowed range is from100to500Hz.strengthโ sets the virtual bass strength. Allowed range is from0.5to3. Default value is3.
volume ๐๏ธ
Adjusts the input audio volume. The literal volume knob of the filter world.
It accepts the following parameters:
volume
Sets the audio volume expression.
Output values are clipped to the maximum value. ๐ฅ
The output audio volume is given by the relation:
<output_volume> = <volume> * <input_volume>
The default value for volume is "1.0".
precision
This parameter represents the mathematical precision.
It determines which input sample formats will be allowed, which affects the precision of the volume scaling:
fixedโ 8-bit fixed-point; this limits input sample format toU8,S16, andS32.floatโ 32-bit floating-point; this limits input sample format toFLT. (default)doubleโ 64-bit floating-point; this limits input sample format toDBL.
replaygain
Chooses the behaviour on encountering ReplayGain side data in input frames:
dropโ remove ReplayGain side data, ignoring its contents (the default).ignoreโ ignore ReplayGain side data, but leave it in the frame.trackโ prefer the track gain, if present.albumโ prefer the album gain, if present.
replaygain_preamp
Pre-amplification gain in dB to apply to the selected replaygain gain.
Default value for replaygain_preamp is 0.0.
replaygain_noclip
Prevents clipping by limiting the gain applied.
Default value for replaygain_noclip is 1.
eval
Sets when the volume expression is evaluated.
It accepts the following values:
onceโ only evaluate the expression once during filter initialization, or when thevolumecommand is sentframeโ evaluate the expression for each incoming frame
Default value is once.
The volume expression can contain the following parameters:
nโ frame number (starting at zero)nb_channelsโ number of channelsnb_consumed_samplesโ number of samples consumed by the filternb_samplesโ number of samples in the current frameposโ original frame position in the file; deprecated, do not use ๐ptsโ frame PTSsample_rateโ sample ratestartptsโ PTS at start of streamstarttโ time at start of streamtโ frame timetbโ timestamp timebasevolumeโ last set volume value
Note that whenevalis set toonce, only thesample_rateandtbvariables are available โ all other variables will evaluate toNAN. ๐
Commands
This filter supports the following commands:
volumeโ modify the volume expression. The command accepts the same syntax as the corresponding option.
If the specified expression is not valid, it is kept at its current value. (She said "no thanks" to your nonsense expression. ๐ )
Examples
- Halve the input audio volume:
volume=volume=0.5
volume=volume=1/2
volume=volume=-6.0206dB
In all the above examples the named key for volume can be omitted, for example like in:
volume=0.5
- Increase input audio power by 6 decibels using fixed-point precision:
volume=volume=6dB:precision=fixed
- Fade volume after time 10 with an annihilation period of 5 seconds:
volume='if(lt(t,10),1,max(1-(t-10)/5,0))':eval=frame
volumedetect ๐
Detects the volume of the input video. Yes, video โ that's what the page says, we're keeping it. ๐
The filter has no parameters. It supports only 16-bit signed integer samples, so the input will be converted when needed. Statistics about the volume will be printed in the log when the input stream end is reached.
In particular it will show the mean volume (root mean square), maximum volume (on a per-sample basis), and the beginning of a histogram of the registered volume values (from the maximum value to a cumulated 1/1000 of the samples).
All volumes are in decibels relative to the maximum PCM value.
Examples
Here is an excerpt of the output:
[Parsed_volumedetect_0 0xa23120] mean_volume: -27 dB
[Parsed_volumedetect_0 0xa23120] max_volume: -4 dB
[Parsed_volumedetect_0 0xa23120] histogram_4db: 6
[Parsed_volumedetect_0 0xa23120] histogram_5db: 62
[Parsed_volumedetect_0 0xa23120] histogram_6db: 286
[Parsed_volumedetect_0 0xa23120] histogram_7db: 1042
[Parsed_volumedetect_0 0xa23120] histogram_8db: 2551
[Parsed_volumedetect_0 0xa23120] histogram_9db: 4609
[Parsed_volumedetect_0 0xa23120] histogram_10db: 8409
It means that:
- The mean square energy is approximately -27 dB, or 10^-2.7.
- The largest sample is at -4 dB, or more precisely between -4 dB and -5 dB.
- There are 6 samples at -4 dB, 62 at -5 dB, 286 at -6 dB, etc.
In other words, raising the volume by +4 dB does not cause any clipping, raising it by +5 dB causes clipping for 6 samples, etc. โก
whisper ๐ง
It runs automatic speech recognition using OpenAI's Whisper model. Literally the coolest thing on this page, ngl.
It requires the whisper.cpp library (https://github.com/ggml-org/whisper.cpp) as a prerequisite. After installing the library it can be enabled using: ./configure --enable-whisper.
The filter has the following options:
modelโ the file path of the downloaded whisper.cpp model (mandatory). You HAVE to set this one bestie, no skipping. ๐languageโ the language to use for transcription ('auto'for auto-detect). Default value:"auto"queueโ how big the queue into the filter can get before the audio actually gets processed by whisper. Small value = your audio stream gets processed more often, but ngl the transcription quality drops and it eats way more processing power. Large value (like10-20s) = more accurate results using less CPU (basically like using thewhisper-clitool), but the transcription latency goes up, so it's not useful for real-time streams. Lowkey consider using thevad_modeloption together with a large queue value. Default value:"3"โจuse_gpuโ whether GPU support should be on. Default value:"true"gpu_deviceโ which GPU device index to use. Default value:"0"destinationโ if you set this, the transcription output goes to the file or URL you name (use one of the FFmpeg AVIO protocols); otherwise it just gets logged as info messages. The output is also dropped into the"lavfi.whisper.text"frame metadata. Heads up: if the destination is a file and it already exists, it gets overwritten, no cap. ๐formatโ the destination format string; it can be"text"(only the transcribed text goes to the destination),"srt"(subtitle format) or"json". Default value:"text"max_lenโ maximum segment length in characters. When you set it to something greater than0, transcription segments get split so they don't go over this length. Super handy for making subtitles with shorter lines. Default value:"0"vad_modelโ path to the VAD model file. If you set it, the filter loads an extra voice activity detection module (https://github.com/snakers4/silero-vad) that gets used to fragment the audio queue; use this option by setting a valid path grabbed from the whisper.cpp repository (e.g."../whisper.cpp/models/ggml-silero-v5.1.2.bin") and bump thequeueparameter up higher (e.g.20).vad_thresholdโ the VAD threshold to use. Default value:"0.5"vad_min_speech_durationโ the minimum VAD speaking duration. Default value:"0.1"vad_min_silence_durationโ the minimum VAD silence duration. Default value:"0.5"
Examples ๐
- Run a transcription with srt file generation:
ffmpeg -i input.mp4 -vn -af "whisper=model=../whisper.cpp/models/ggml-base.en.bin\
:language=en\
:queue=3\
:destination=output.srt\
:format=srt" -f null -
- Run a transcription and send the output in JSON format to an HTTP service:
ffmpeg -i input.mp4 -vn -af "whisper=model=../whisper.cpp/models/ggml-base.en.bin\
:language=en\
:queue=3\
:destination=http\\://localhost\\:3000\
:format=json' -f null -
- Transcribe the microphone input using the VAD option:
ffmpeg -loglevel warning -f pulse -i default \
-af 'highpass=f=200,lowpass=f=3000,whisper=model=../whisper.cpp/models/ggml-medium.bin\
:language=en\
:queue=10\
:destination=-\
:format=json\
:vad_model=../whisper.cpp/models/ggml-silero-v5.1.2.bin' -f null -
๐ AUDIO SOURCES ๐
Okay so below is the whole rundown of the audio sources that are available rn. Buckle up, bestie. ๐ฆ
abuffer
Buffers audio frames and makes them available to the filter chain. Iconic little middleman behavior.
This source is mainly meant for programmatic use, in particular through the interface defined in libavfilter/buffersrc.h.
It accepts these parameters:
time_baseโ the timebase used for timestamps of submitted frames. It's gotta be either a floating-point number or innumerator/denominatorform.sample_rateโ the sample rate of the incoming audio buffers.sample_fmtโ the sample format of the incoming audio buffers. Either a sample format name or its matching integer representation from theenum AVSampleFormatinlibavutil/samplefmt.hchannel_layoutโ the channel layout of the incoming audio buffers. Either a channel layout name fromchannel_layout_mapinlibavutil/channel_layout.cor its matching integer representation from theAV_CH_LAYOUT_*macros inlibavutil/channel_layout.hchannelsโ the number of channels of the incoming audio buffers. If bothchannelsandchannel_layoutare specified, then they have to be consistent with each other. No contradicting yourself, periodt.
Examples
abuffer=sample_rate=44100:sample_fmt=s16p:channel_layout=stereo
will tell the source to accept planar 16bit signed stereo at 44100Hz. Since the sample format named "s16p" corresponds to the number 6 and the "stereo" channel layout corresponds to the value 0x3, this is equivalent to:
abuffer=sample_rate=44100:sample_fmt=6:channel_layout=0x3
aevalsrc
Generates an audio signal specified by an expression. Math but make it sound. ๐งฎโจ
This source takes one or more expressions as input (one for each channel), which get evaluated and used to generate the matching audio signal.
This source accepts the following options:
exprsโ sets the'|'-separated expressions list for each separate channel. If thechannel_layoutoption isn't specified, the selected channel layout depends on how many expressions you provided. Otherwise the last specified expression gets applied to the remaining output channels.channel_layout,cโ sets the channel layout. The number of channels in the specified layout must equal the number of specified expressions.duration,dโ sets the minimum duration of the sourced audio. See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. Note that the resulting duration may be greater than the specified duration, since the generated audio is always cut at the end of a complete frame. If it's not specified, or the expressed duration is negative, the audio is supposed to be generated forever.nb_samples,nโ sets the number of samples per channel per each output frame, defaults to1024.sample_rate,sโ specifies the sample rate, defaults to44100.
Each expression in exprs can contain these constants:
nโ number of the evaluated sample, starting from0tโ time of the evaluated sample expressed in seconds, starting from0sโ sample rate
Examples
- Generate silence:
aevalsrc=0
- Generate a sin signal with frequency of 440 Hz, set sample rate to 8000 Hz:
aevalsrc="sin(440*2*PI*t):s=8000"
- Generate a two channels signal, specify the channel layout (Front Center + Back Center) explicitly:
aevalsrc="sin(420*2*PI*t)|cos(430*2*PI*t):c=FC|BC"
- Generate white noise:
aevalsrc="-2+random(0)"
- Generate an amplitude modulated signal:
aevalsrc="sin(10*2*PI*t)*sin(880*2*PI*t)"
- Generate 2.5 Hz binaural beats on a 360 Hz carrier:
aevalsrc="0.1*sin(2*PI*(360-2.5/2)*t) | 0.1*sin(2*PI*(360+2.5/2)*t)"
afdelaysrc
Generates fractional delay FIR coefficients. So specific, so niche, we love her. ๐
The resulting stream can be used with the afir filter for filtering the audio signal.
The filter accepts these options:
delay,dโ sets the fractional delay. Default is0.sample_rate,rโ sets the sample rate, default is44100.nb_samples,nโ sets the number of samples per each frame. Default is1024.taps,tโ sets the number of filter coefficients in the output audio stream. Default value is0.channel_layout,cโ specifies the channel layout, and can be a string representing a channel layout. The default value ofchannel_layoutis"stereo".
afireqsrc
Generates FIR equalizer coefficients. Yes she's the equalizer baddie. ๐๏ธ
The resulting stream can be used with the afir filter for filtering the audio signal.
The filter accepts the following options:
preset,pโ sets the equalizer preset. Default preset is"flat". The available presets are:customflatacousticbassbeatsclassiccleardeep bassdubstepelectronichard-stylehip-hopjazzmetalmoviepopr&brockvocal booster
gains,gโ sets custom gains for each band. Only used if thepresetoption is set to"custom". Gains are separated by white spaces and each gain is set in dBFS. Default is"0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0".bands,bโ sets the custom bands from where the custom equalizer gains are set. This must be in strictly increasing order. Only used if thepresetoption is set to"custom". Bands are separated by white spaces and each band represents frequency in Hz. Default is"25 40 63 100 160 250 400 630 1000 1600 2500 4000 6300 10000 16000 24000".taps,tโ sets the number of filter coefficients in the output audio stream. Default value is4096.sample_rate,rโ sets the sample rate of the output audio stream, default is44100.nb_samples,nโ sets the number of samples per each frame in the output audio stream. Default is1024.interp,iโ sets the interpolation method for the FIR equalizer coefficients. Can be"linear"or"cubic".phase,hโ sets the phase type of the FIR filter. Can be"linear"or"min": minimum-phase. Default is minimum-phase filter.
afirsrc
Generates FIR coefficients using the frequency sampling method. Frequency sampling is lowkey a flex, ngl. ๐ฅ
The resulting stream can be used with the afir filter for filtering the audio signal.
The filter accepts the following options:
taps,tโ sets the number of filter coefficients in the output audio stream. Default value is1025.frequency,fโ sets the frequency points from where magnitude and phase are set. This must be in non decreasing order, and the first element must be0, while the last element must be1. Elements are separated by white spaces.magnitude,mโ sets the magnitude value for every frequency point set byfrequency. The number of values must be the same as the number of frequency points. Values are separated by white spaces.phase,pโ sets the phase value for every frequency point set byfrequency. The number of values must be the same as the number of frequency points. Values are separated by white spaces.sample_rate,rโ sets the sample rate, default is44100.nb_samples,nโ sets the number of samples per each frame. Default is1024.win_func,wโ sets the window function. Default isblackman.
anullsrc
The null audio source โ it just hands you back unprocessed audio frames, like, the most nothing-ever generator. It's mainly useful as a template, and for analysis / debugging tools, or as the source for filters that literally ignore their input data (the sox synth filter is the classic example, iykyk).
This source accepts the following options:
channel_layout,clโ sets the channel layout. Can be an integer or a string that represents a channel layout. Default is"stereo". If you wanna see the full mapping between strings and channel layout values, check thechannel_layout_mapdefinition inlibavutil/channel_layout.c. ๐sample_rate,rโ sets the sample rate, defaults to44100.nb_samples,nโ set the number of samples per requested frames.duration,dโ set the duration of the sourced audio. See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. If it's not specified, or the expressed duration is negative, the audio is supposed to be generated forever. โพ๏ธ
Examples
- Set the sample rate to 48000 Hz and the channel layout to
AV_CH_LAYOUT_MONO:
anullsrc=r=48000:cl=4
- Do the same operation with a more obvious syntax:
anullsrc=r=48000:cl=mono
ok important bestie: all the parameters need to be explicitly defined. no vibes-based defaults here, define them or perish ๐
flite
Synthesize a voice utterance using the libflite library. it literally talks, iconic.
To enable compilation of this filter you need to configure FFmpeg with --enable-libflite.
heads up ๐ซถ โ versions of the flite library prior to 2.0 are not thread-safe. keep that in mind before you come for me.
The filter accepts the following options:
list_voicesโ if set to1, list the names of the available voices and exit immediately. Default value is0.nb_samples,nโ set the maximum number of samples per frame. Default value is512.textfileโ set the filename containing the text to speak.textโ set the text to speak.voice,vโ set the voice to use for the speech synthesis. Default value is"kal". See also thelist_voicesoption.
Examples
- Read from file
speech.txt, and synthesize the text using the standard flite voice:
flite=textfile=speech.txt
- Read the specified text selecting the
"slt"voice:
flite=text='So fare thee well, poor devil of a Sub-Sub, whose commentator I am':voice=slt
- Input text to
ffmpeg:
ffmpeg -f lavfi -i flite=text='So fare thee well, poor devil of a Sub-Sub, whose commentator I am':voice=slt
- Make
ffplayspeak the specified text, using"flite"and the"lavfi"device:
ffplay -f lavfi flite=text='No more be grieved for which that thou hast done.'
For more information about libflite, check: <http://www.festvox.org/flite/> โจ
anoisesrc
Generate a noise audio signal. yes. just noise. the ambient sound of my brain at 3am ๐
The filter accepts the following options:
sample_rate,rโ specify the sample rate. Default value is48000Hz.amplitude,aโ specify the amplitude (0.0-1.0) of the generated audio stream. Default value is1.0.duration,dโ specify the duration of the generated audio stream. Not specifying this option results in noise with an infinite length. ๐color,colour,cโ specify the color of noise. Available noise colors arewhite,pink,brown,blue,violetandvelvet. Default color iswhite.seed,sโ specify a value used to seed the PRNG.nb_samples,nโ set the number of samples per each output frame, default is1024.densityโ set the density (0.0-1.0) for the velvet noise generator, default is0.05.
Examples
- Generate 60 seconds of pink noise, with a 44.1 kHz sampling rate and an amplitude of 0.5:
anoisesrc=d=60:c=pink:r=44100:a=0.5
hilbert
Generate odd-tap Hilbert transform FIR coefficients. fancy math, no cap.
The resulting stream can be used with the afir filter for phase-shifting the signal by 90 degrees.
This is used in many matrix coding schemes and for analytic signal generation. The process is often written as a multiplication by i (or j), the imaginary unit. ๐ง
The filter accepts the following options:
sample_rate,sโ set sample rate, default is44100.taps,tโ set length of FIR filter, default is22051.nb_samples,nโ set number of samples per each frame.win_func,wโ set window function to be used when generating FIR coefficients.
sinc
Generate a sinc kaiser-windowed low-pass, high-pass, band-pass, or band-reject FIR coefficients. that's a mouthful and honestly? she ate. ๐
The resulting stream can be used with the afir filter for filtering the audio signal.
The filter accepts the following options:
sample_rate,rโ set sample rate, default is44100.nb_samples,nโ set number of samples per each frame. Default is1024.hpโ set high-pass frequency. Default is0.lpโ set low-pass frequency. Default is0. If high-pass frequency is lower than low-pass frequency and low-pass frequency is higher than0, then the filter will create band-pass filter coefficients, otherwise band-reject filter coefficients. keep that logic in your notes bestie ๐ซถphaseโ set filter phase response. Default is50. Allowed range is from0to100.betaโ set Kaiser window beta.attโ set stop-band attenuation. Default is120dB, allowed range is from40to180dB.roundโ enable rounding, by default is disabled.hptapsโ set number of taps for high-pass filter.lptapsโ set number of taps for low-pass filter.
sine
Generate an audio signal made of a sine wave with amplitude 1/8.
The audio signal is bit-exact. โญ
The filter accepts the following options:
frequency,fโ set the carrier frequency. Default is440Hz.beep_factor,bโ enable a periodic beep every second with frequencybeep_factortimes the carrier frequency. Default is0, meaning the beep is disabled.sample_rate,rโ specify the sample rate, default is44100.duration,dโ specify the duration of the generated audio stream.samples_per_frameโ set the number of samples per output frame.
The expression can contain the following constants:
nโ the (sequential) number of the output audio frame, starting from0.ptsโ the PTS (Presentation TimeStamp) of the output audio frame, expressed inTBunits.tโ the PTS of the output audio frame, expressed in seconds.TBโ the timebase of the output audio frames.
Default is 1024.
Examples
- Generate a simple 440 Hz sine wave:
sine
- Generate a 220 Hz sine wave with a 880 Hz beep each second, for 5 seconds:
sine=220:4:d=5
sine=f=220:b=4:d=5
sine=frequency=220:beep_factor=4:duration=5
- Generate a 1 kHz sine wave following
"1602,1601,1602,1601,1602"NTSC pattern:
sine=1000:samples_per_frame='st(0,mod(n,5)); 1602-not(not(eq(ld(0),1)+eq(ld(0),3)))'
๐ธ AUDIO SINKS ๐ธ
Below is a description of the currently available audio sinks. (the place where your audio goes to rest ๐)
abuffersink
Buffer audio frames, and make them available to the end of filter chain.
This sink is mainly intended for programmatic use, in particular through the interface defined in libavfilter/buffersink.h or the options system.
It accepts a pointer to an AVABufferSinkContext structure, which defines the incoming buffers' formats, to be passed as the opaque parameter to avfilter_init_filter for initialization.
anullsink
Null audio sink; do absolutely nothing with the input audio. it's giving "i'm just here for the vibes" โ mainly useful as a template and for use in analysis / debugging tools. ๐
๐ VIDEO FILTERS ๐
When you configure your FFmpeg build, you can disable any of the existing filters using --disable-filters. The configure output will show the video filters included in your build.
Below is a description of the currently available video filters. let's get into it ๐ฌ
addroi
Mark a region of interest in a video frame.
The frame data is passed through unchanged, but metadata is attached to the frame indicating regions of interest which can affect the behaviour of later encoding. Multiple regions can be marked by applying the filter multiple times.
xโ region distance in pixels from the left edge of the frame.yโ region distance in pixels from the top edge of the frame.wโ region width in pixels.hโ region height in pixels.
The parameters x, y, w and h are expressions, and may contain the following variables:
iwโ width of the input frame.ihโ height of the input frame.qoffsetโ quantisation offset to apply within the region.
This must be a real value in the range -1 to +1. A value of zero indicates no quality change. A negative value asks for better quality (less quantisation), while a positive value asks for worse quality (greater quantisation).
The range is calibrated so that the extreme values indicate the largest possible offset โ if the rest of the frame is encoded with the worst possible quality, an offset of -1 indicates that this region should be encoded with the best possible quality anyway. Intermediate values are then interpolated in some codec-dependent way.
For example, in 10-bit H.264 the quantisation parameter varies between -12 and 51. A typical qoffset value of -1/10 therefore indicates that this region should be encoded with a QP around one-tenth of the full range better than the rest of the frame. So, if most of the frame were to be encoded with a QP of around 30, this region would get a QP of around 24 (an offset of approximately -1/10 * (51 - -12) = -6.3). An extreme value of -1 would indicate that this region should be encoded with the best possible quality regardless of the treatment of the rest of the frame โ that is, should be encoded at a QP of -12. ๐ค math girlies rise
clearโ if set to true, remove any existing regions of interest marked on the frame before adding the new one.
Examples
- Mark the centre quarter of the frame as interesting.
addroi=iw/4:ih/4:iw/2:ih/2:-1/10
- Mark the 100-pixel-wide region on the left edge of the frame as very uninteresting (to be encoded at much lower quality than the rest of the frame).
addroi=0:0:100:ih:+1/5
alphaextract
Extract the alpha component from the input as a grayscale video. This is especially useful with the alphamerge filter. โจ
alphamerge
Add or replace the alpha component of the primary input with the grayscale value of a second input. This is intended for use with alphaextract to allow the transmission or storage of frame sequences that have alpha in a format that doesn't support an alpha channel. ๐ฆ
For example, to reconstruct full frames from a normal YUV-encoded video and a separate video created with alphaextract, you might use:
movie=in_alpha.mkv [alpha]; [in][alpha] alphamerge [out]
amplify
Okay so this one literally turns up the volume on the differences between the current pixel and the pixels sitting in the same spot on neighboring frames. Little differences get louder โจ
It takes these options:
radiusโ sets the frame radius. Default is2. Allowed range is1to63. Bestie, for example a radius of3tells the filter to average7frames together ๐ซถfactorโ sets the factor used to amplify the difference. Default is2. Allowed range is0to65535.thresholdโ sets the threshold for difference amplification. Any difference greater than or equal to this value will not alter the source pixel. Default is10. Allowed range is0to65535.toleranceโ sets the tolerance for difference amplification. Any difference lower than this value will not alter the source pixel. Default is0. Allowed range is0to65535.lowโ sets the lower limit for changing the source pixel. Default is65535. Allowed range is0to65535. This option controls the maximum possible value that will decrease the source pixel value.highโ sets the high limit for changing the source pixel. Default is65535. Allowed range is0to65535. This option controls the maximum possible value that will increase the source pixel value.planesโ sets which planes to filter. Default is all. Allowed range is0to15.
Commands
This filter supports the following commands, and each one corresponds to the option of the same name:
factorthresholdtolerancelowhighplanes
ass
Same thing as the subtitles filter, except it does not need libavcodec and libavformat to work. The tradeoff? It's limited to ASS (Advanced Substation Alpha) subtitle files. iykyk ๐
On top of the common options it inherits from the subtitles filter, it takes this one:
shapingโ sets the shaping engine.
Available values are:
autoโ the default libass shaping engine, which is the best available. ๐simpleโ a fast, font-agnostic shaper that can do only substitutions.complexโ a slower shaper using OpenType for substitutions and positioning.
The default is "auto".
atadenoise
Applies an Adaptive Temporal Averaging Denoiser to the video input. Say bye to the grain, bestie ๐ฆ
The filter accepts these options:
0aโ sets threshold A for the 1st plane. Default is0.02. Valid range is0to0.3.0bโ sets threshold B for the 1st plane. Default is0.04. Valid range is0to5.1aโ sets threshold A for the 2nd plane. Default is0.02. Valid range is0to0.3.1bโ sets threshold B for the 2nd plane. Default is0.04. Valid range is0to5.2aโ sets threshold A for the 3rd plane. Default is0.02. Valid range is0to0.3.2bโ sets threshold B for the 3rd plane. Default is0.04. Valid range is0to5.
Threshold A is designed to react on abrupt changes in the input signal, and threshold B is designed to react on continuous changes in the input signal. Different jobs, both slaying ๐
sโ sets the number of frames the filter will use for averaging. Default is9. Must be an odd number in range[5, 129].pโ sets what planes of the frame the filter will use for averaging. Default is all.aโ sets what variant of algorithm the filter will use for averaging. Default is"p"(parallel). Alternatively it can be set to"s"(serial).
Parallel can be faster than serial, but the other way around is never true. Parallel will abort early on the first change being greater than the thresholds, while serial will keep processing the other side of frames if they are equal to or below the thresholds. Ngl that's kind of iconic ๐ฅ
0s,1s,2sโ sets sigma for the 1st plane, 2nd plane or 3rd plane. Default is32767. Valid range is0to32767. This option controls the weight for each pixel in the radius defined by size. The default value means every pixel has the same weight. Setting this option to0effectively disables filtering. ๐ซ
Commands
This filter supports the same commands as the options, except the option "s". The command accepts the same syntax as the corresponding option.
avgblur
Applies an average blur filter. Soft focus moment โจ
Options:
sizeXโ sets the horizontal radius size.planesโ sets which planes to filter. By default all planes are filtered.sizeYโ sets the vertical radius size; if zero, it will be the same as"sizeX". Default is0.
Commands
This filter supports the same commands as the options, and the command accepts the same syntax as the corresponding option.
If the specified expression is not valid, it is kept at its current value. No chaos, no drama ๐
backgroundkey</backgroundkey>
Turns a static background into transparency. Poof, gone, bye ๐
Takes this option:
thresholdโ threshold for scene change detection.similarityโ similarity percentage with the background.blendโ sets the blend amount for pixels that are not similar.
Commands
This filter supports all of the above options as commands.
bbox
Computes the bounding box for the non-black pixels in the input frame luma plane. Detective mode ๐
It computes the bounding box containing all the pixels with a luma value greater than the minimum allowed value. The parameters describing the bounding box are printed on the filter log.
Takes this option:
min_valโ sets the minimal luma value. Default is16.
Commands
This filter supports all of the above options as commands.
bilateral
Applies a bilateral filter โ spatial smoothing while preserving edges. Smooth and sharp, she contains multitudes ๐
Options:
sigmaSโ sets sigma of the gaussian function used to calculate spatial weight. Allowed range is0to512. Default is0.1.sigmaRโ sets sigma of the gaussian function used to calculate range weight. Allowed range is0to1. Default is0.1.planesโ sets planes to filter. Default is first only.
Commands
This filter supports all of the above options as commands.
bitplanenoise</bitplanenoise>
Shows and measures bit plane noise. Numbers time, bestie ๐ง
Options:
bitplaneโ sets which plane to analyze. Default is1.filterโ filters out noisy pixels from the"bitplane"set above. Default is disabled.
blackdetect, blackdetect_vulkan
Detects video intervals that are (almost) completely black. Super useful for spotting chapter transitions, commercials, or invalid recordings. ๐
The filter outputs its detection analysis to both the log and the frame metadata. If a black segment of at least the specified minimum duration is found, a line with the start and end timestamps as well as the duration is printed to the log with level "info". On top of that, a log line with level "debug" is printed per frame showing the black amount detected for that frame.
It also attaches metadata to the first frame of a black segment with key "lavfi.black_start", and to the first frame after the black segment ends with key "lavfi.black_end". The value is the frame's timestamp. This metadata is added regardless of the minimum duration specified โ no cap, it always tags them ๐
Options:
black_min_duration,dโ sets the minimum detected black duration, expressed in seconds. It must be a non-negative floating point number.
Default value is 2.0.
picture_black_ratio_th,pic_thโ sets the threshold for considering a picture "black". Expresses the minimum value for the ratio:
<nb_black_pixels> / <nb_pixels>
for which a picture is considered black. Default value is 0.98.
pixel_black_th,pix_thโ sets the threshold for considering a pixel "black".
The threshold expresses the maximum pixel luma value for which a pixel is considered "black". The provided value is scaled according to the following equation:
<absolute_threshold> = <luma_minimum_value> + <pixel_black_th> * <luma_range_size>
luma_range_size and luma_minimum_value depend on the input video format. The range is [0-255] for YUV full-range formats and [16-235] for YUV non full-range formats.
Default value is 0.10.
alphaโ if true, check the alpha channel instead of the luma channel. This detects frames that are (almost) transparent, instead of frames that are almost black. Spiritually the same vibe check, different channel ๐ป
Default value is disabled.
The following example sets the maximum pixel threshold to the minimum value, and detects only black intervals of 2 or more seconds:
blackdetect=d=2:pix_th=0.00
blackframe
Detects frames that are (almost) completely black. Can be useful for detecting chapter transitions or commercials. The output lines consist of the frame number of the detected frame, the percentage of blackness, the position in the file if known or -1, and the timestamp in seconds. ๐ต๏ธโโ๏ธ
In order to display the output lines, you need to set the loglevel at least to the AV_LOG_INFO value. Don't forget or you'll see nothing and be confused, and I refuse to let that be your story ๐ญ
This filter exports frame metadata "lavfi.blackframe.pblack". The value represents the percentage of pixels in the picture that are below the threshold value.
It accepts the following parameters:
amountโ the percentage of the pixels that have to be below the threshold; it defaults to98.threshold,threshโ the threshold below which a pixel value is considered black; it defaults to32.
blend
Blends two video frames into each other. Collab era ๐
The "blend" filter takes two input streams and outputs one stream. The first input is the "top" layer and the second input is the "bottom" layer. By default, the output terminates when the longest input terminates.
The "tblend" (time blend) filter takes two consecutive frames from a single stream, and outputs the result obtained by blending the new frame on top of the old frame.
A description of the accepted options follows:
c0_modec1_modec2_modec3_modeall_mode
Set the blend mode for a specific pixel component, or for all pixel components in the case of all_mode. Default value is "normal".
Available values for component modes are:
additionandaveragebleachburndarkendifferencedividedodgeexclusionextremityfreezegeometricglowgrainextractgrainmergehardlighthardmixhardoverlayharmonicheatinterpolatelightenlinearlightmultiplymultiply128negationnormaloroverlayphoenixpinlightreflectscreensoftdifferencesoftlightstainsubtractvividlightxor
okay that's the whole mode menu, bestie, we're done with that list ๐ moving on!!
c0_opacity,c1_opacity,c2_opacity,c3_opacity,all_opacityโ set the blend opacity for one specific pixel component, or like, for all of them if you useall_opacity๐ซถ these only do anything when you're using the pixel-component blend modes, fyi.c0_expr,c1_expr,c2_expr,c3_expr,all_exprโ set the blend expression for a specific pixel component, or all of them withall_exprโจ tiny heads up tho: if you set these, the related mode options just get ignored, lowkey ghosted.
The expressions get to use these variables:
Nโ the sequential number of the filtered frame, starting from 0.X,Yโ the coordinates of the current sample.W,Hโ the width and height of the currently filtered plane.SW,SHโ width and height scale for the plane being filtered. It's the ratio between the dimensions of the current plane and the luma plane, so like, for ayuv420pframe the values are1,1for the luma plane and0.5,0.5for the chroma planes.Tโ time of the current frame, expressed in seconds.TOP,Aโ value of the pixel component at the current location for the first video frame (top layer).BOTTOM,Bโ value of the pixel component at the current location for the second video frame (bottom layer).
The blend filter also supports the framesync options ๐
Examples
- Apply transition from bottom layer to top layer in first 10 seconds:
blend=all_expr='A*(if(gte(T,10),1,T/10))+B*(1-(if(gte(T,10),1,T/10)))'
- Apply linear horizontal transition from top layer to bottom layer:
blend=all_expr='A*(X/W)+B*(1-X/W)'
- Apply 1x1 checkerboard effect:
blend=all_expr='if(eq(mod(X,2),mod(Y,2)),A,B)'
- Apply uncover left effect:
blend=all_expr='if(gte(N*SW+X,W),A,B)'
- Apply uncover down effect:
blend=all_expr='if(gte(Y-N*SH,0),A,B)'
- Apply uncover up-left effect:
blend=all_expr='if(gte(T*SH*40+Y,H)*gte((T*40*SW+X)*W/H,W),A,B)'
- Split diagonally video and shows top and bottom layer on each side:
blend=all_expr='if(gt(X,Y*(W/H)),A,B)'
- Display differences between the current and the previous frame:
tblend=all_mode=grainextract
Commands
This filter supports same commands as options ๐ yes bestie, you can fiddle with it live.
๐งฑ blockdetect
Determines the blockiness of frames without altering the input frames โ it's purely a measuring girlie, no touchy ๐ โโ๏ธ
Based on Remco Muijs and Ihor Kirenko: "A no-reference blocking artifact measure for adaptive video processing." 2005 13th European signal processing conference.
The filter accepts the following options:
period_min,period_maxโ set the minimum and maximum values for determining pixel grids (periods). Default values are[3,24].planesโ set planes to filter. Default is first only.
Examples
- Determine blockiness for the first plane and search for periods within
[8,32]:
blockdetect=period_min=8:period_max=32:planes=1
๐ซ๏ธ blurdetect
Determines the blurriness of frames without altering the input frames. Based on Marziliano, Pina, et al. "A no-reference perceptual blur metric." It's got a block-based abbreviation too, fancy.
The filter accepts the following options:
low,highโ set the low and high threshold values used by the Canny thresholding algorithm.
So the high threshold picks out the "strong" edge pixels, and then those get connected through 8-connectivity with the "weak" edge pixels that the low threshold selected ๐
low and high have to be chosen in the range [0,1], and low should be lesser or equal to high (don't be chaotic about it).
Default value for low is 20/255, and default value for high is 50/255.
radiusโ define the radius to search around an edge pixel for local maxima.block_pctโ determine blurriness only for the most significant blocks, given in percentage.block_widthโ determine blurriness for blocks of width block_width. If set to any value smaller 1, no blocks are used and the whole image is processed as one, no matter whatblock_heightsays.block_heightโ determine blurriness for blocks of height block_height. If set to any value smaller 1, no blocks are used and the whole image is processed as one, no matter whatblock_widthsays.planesโ set planes to filter. Default is first only.
Examples
- Determine blur for 80% of most significant 32x32 blocks:
blurdetect=block_width=32:block_height=32:block_pct=80
๐ง bm3d
Denoise frames using the Block-Matching 3D algorithm โ it's giving fancy-science-girlie energy fr fr ๐ง
The filter accepts the following options.
sigmaโ set denoising strength. Default value is1. Allowed range is from0to999.9. Heads up tho: the denoising algorithm is very sensitive to sigma, so adjust it according to the source, okay? ๐ญblockโ set local patch size. This sets dimensions in 2D.bstepโ set sliding step for processing blocks. Default value is4. Allowed range is from1to64. Smaller values allow processing more reference blocks and is slower (iconic tradeoff ๐ ).groupโ set maximal number of similar blocks for 3rd dimension. Default value is1. When set to1, no block matching is done. Larger values allow more blocks in a single group. Allowed range is from1to256.rangeโ set radius for search block matching. Default is9. Allowed range is from1toINT32_MAX.mstepโ set step between two search locations for block matching. Default is1. Allowed range is from1to64. Smaller is slower.thmseโ set threshold of mean square error for block matching. Valid range is0toINT32_MAX.hdthrโ set thresholding parameter for hard thresholding in 3D transformed domain. Larger values result in stronger hard-thresholding filtering in the frequency domain.estimโ set filtering estimation mode. Can bebasicorfinal. Default isbasic.refโ if enabled, the filter will use the 2nd stream for block matching. Default is disabled forbasicvalue of theestimoption, and always enabled if the value ofestimisfinal.planesโ set planes to filter. Default is all available except alpha.
Examples
- Basic filtering with bm3d:
bm3d=sigma=3:block=4:bstep=2:group=1:estim=basic
- Same as above, but filtering only luma:
bm3d=sigma=3:block=4:bstep=2:group=1:estim=basic:planes=1
- Same as above, but with both estimation modes:
split[a][b],[a]bm3d=sigma=3:block=4:bstep=2:group=1:estim=basic[a],[b][a]bm3d=sigma=3:block=4:bstep=2:group=16:estim=final:ref=1
- Same as above, but prefilter with nlmeans filter instead:
split[a][b],[a]nlmeans=s=3:r=7:p=3[a],[b][a]bm3d=sigma=3:block=4:bstep=2:group=16:estim=final:ref=1
๐ธ boxblur
Apply a boxblur algorithm to the input video. Soft-focus main character vibes โจ
It accepts the following parameters:
luma_radius,lrluma_power,lpchroma_radius,crchroma_power,cpalpha_radius,aralpha_power,ap
A description of the accepted options follows.
luma_radius,lr/chroma_radius,cr/alpha_radius,arโ set an expression for the box radius in pixels used for blurring the corresponding input plane.
The radius value must be a non-negative number, and must not be greater than the value of the expression min(w,h)/2 for the luma and alpha planes, and of min(cw,ch)/2 for the chroma planes. Respect the limits bestie ๐
Default value for luma_radius is 2. If not specified, chroma_radius and alpha_radius default to the corresponding value set for luma_radius.
The expressions can contain the following constants:
w,hโ the input width and height in pixels.cw,chโ the input chroma image width and height in pixels.hsub,vsubโ the horizontal and vertical chroma subsample values. For example, for the pixel formatyuv422p,hsubis 2 andvsubis 1.
luma_power,lp/chroma_power,cp/alpha_power,apโ specify how many times the boxblur filter is applied to the corresponding plane.
Default value for luma_power is 2. If not specified, chroma_power and alpha_power default to the corresponding value set for luma_power.
A value of 0 will disable the effect (so like, zero blur, ghost mode ๐ป).
Examples
- Apply a boxblur filter with the luma, chroma, and alpha radii set to 2:
boxblur=luma_radius=2:luma_power=1
boxblur=2:1
- Set the luma radius to 2, and alpha and chroma radius to 0:
boxblur=2:1:cr=0:ar=0
- Set the luma and chroma radii to a fraction of the video dimension:
boxblur=luma_radius=min(h\,w)/10:luma_power=1:chroma_radius=min(cw\,ch)/10:chroma_power=1
๐ฆ bwdif
Deinterlace the input video (bwdif stands for "Bob Weaver Deinterlacing Filter" โ yes, that's a real name and yes it's iconic).
Motion adaptive deinterlacing based on yadif with the use of w3fdif and cubic interpolation algorithms. It accepts the following parameters:
modeโ the interlacing mode to adopt. It accepts one of the following values:0,send_frameโ output one frame for each frame.1,send_fieldโ output one frame for each field.
The default value is send_field.
parityโ the picture field parity assumed for the input interlaced video. It accepts one of the following values:0,tffโ assume the top field is first.1,bffโ assume the bottom field is first.-1,autoโ enable automatic detection of field parity.
The default value is auto. If the interlacing is unknown or the decoder does not export this information, top field first will be assumed.
deintโ specify which frames to deinterlace. Accepts one of the following values:0,allโ deinterlace all frames.1,interlacedโ only deinterlace frames marked as interlaced.
The default value is "all". ๐
๐ ccrepack
Repack CEA-708 closed captioning side data.
Okay so this filter fixes various issues seen with commercial encoders related to upstream malformed CEA-708 payloads โ specifically incorrect number of tuples (wrong cc_count for the target FPS), and incorrect ordering of tuples (i.e. the CEA-608 tuples are not at the first entries in the payload). Basically it's the cleanup crew for messy caption data fr fr ๐งนโจ
๐ฆ cas
Apply Contrast Adaptive Sharpen filter to video stream.
The filter accepts the following options:
strengthโ set the sharpening strength. Default value is0.planesโ set planes to filter. Default value is to filter all planes except alpha plane.
๐ฌ Commands
This filter supports same commands as options.
๐ธ chromahold
Remove all color information for all colors except for certain one. The way this one just keeps one color and greys out everything else โ it's giving main character energy ngl ๐
The filter accepts the following options:
colorโ the color which will not be replaced with neutral chroma.similarityโ similarity percentage with the above color.0.01matches only the exact key color, while1.0matches everything.blendโ blend percentage.0.0makes pixels either fully gray, or not gray at all. Higher values result in more preserved color.yuvโ signals that the color passed is already in YUV instead of RGB.
Literal colors like"green"or"red"don't make sense with this enabled anymore. This can be used to pass exact YUV values as hexadecimal numbers. ๐
๐ฌ Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
๐ chromakey
YUV colorspace color/chroma keying. Greenscreen energy, we love to see it ๐
The filter accepts the following options:
colorโ the color which will be replaced with transparency.similarityโ similarity percentage with the key color.0.01matches only the exact key color, while1.0matches everything.blendโ blend percentage.0.0makes pixels either fully transparent, or not transparent at all. Higher values result in semi-transparent pixels, with a higher transparency the more similar the pixels color is to the key color.yuvโ signals that the color passed is already in YUV instead of RGB.
Literal colors like"green"or"red"don't make sense with this enabled anymore. This can be used to pass exact YUV values as hexadecimal numbers. ๐
๐ฌ Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
โจ Examples
- Make every green pixel in the input image transparent:
ffmpeg -i input.png -vf chromakey=green out.png
- Overlay a greenscreen-video on top of a static black background.
ffmpeg -f lavfi -i color=c=black:s=1280x720 -i video.mp4 -shortest -filter_complex "[1:v]chromakey=0x70de77:0.1:0.2[ckout];[0:v][ckout]overlay[out]" -map "[out]" output.mkv
๐ chromanr
Reduce chrominance noise. Lowkey the glow-up filter for grainy footage โจ
The filter accepts the following options:
thresโ set threshold for averaging chrominance values. Sum of absolute difference of Y, U and V pixel components of current pixel and neighbour pixels lower than this threshold will be used in averaging. Luma component is left unchanged and is copied to output. Default value is30. Allowed range is from1to200.sizewโ set horizontal radius of rectangle used for averaging. Allowed range is from1to100. Default value is5.sizehโ set vertical radius of rectangle used for averaging. Allowed range is from1to100. Default value is5.stepwโ set horizontal step when averaging. Default value is1. Allowed range is from1to50. Mostly useful to speed-up filtering.stephโ set vertical step when averaging. Default value is1. Allowed range is from1to50. Mostly useful to speed-up filtering.threyโ set Y threshold for averaging chrominance values. Set finer control for max allowed difference between Y components of current pixel and neighbour pixels. Default value is200. Allowed range is from1to200.threuโ set U threshold for averaging chrominance values. Set finer control for max allowed difference between U components of current pixel and neighbour pixels. Default value is200. Allowed range is from1to200.threvโ set V threshold for averaging chrominance values. Set finer control for max allowed difference between V components of current pixel and neighbour pixels. Default value is200. Allowed range is from1to200.distanceโ set distance type used in calculations.manhattanโ absolute difference.euclideanโ difference squared. Default distance type ismanhattan.
๐ฌ Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
๐ chromashift
Shift chroma pixels horizontally and/or vertically. Justโฆ scootching the chroma around, no biggie ๐ซ
The filter accepts the following options:
cbhโ set amount to shift chroma-blue horizontally.cbvโ set amount to shift chroma-blue vertically.crhโ set amount to shift chroma-red horizontally.crvโ set amount to shift chroma-red vertically.edgeโ set edge mode, can besmear,default, orwarp.
๐ฌ Commands
This filter supports the all above options as commands.
๐ ciescope
Display CIE color diagram with pixels overlaid onto it. Science-y and aesthetic, iconic combo ๐งช๐
The filter accepts the following options:
systemโ set color system.ntsc,470mebu,470bgsmpte240mapplewidergbcie1931rec709,hdtvuhdtv,rec2020dcip3
cieโ set CIE system.xyyucsluv
gamutsโ set what gamuts to draw. Seesystemoption for available values.size,sโ set ciescope size, by default set to512.intensity,iโ set intensity used to map input pixel values to CIE diagram.contrastโ set contrast used to draw tongue colors that are out of active color system gamut.corrgammaโ correct gamma displayed on scope, by default enabled.showwhiteโ show white point on CIE diagram, by default disabled.gammaโ set input gamma. Used only with XYZ input color space.fillโ fill with CIE colors. By default is enabled.
๐ฆ codecview
Visualize information exported by some codecs. Ngl this one is secretly so cool ๐ญ๐ฅ
Some codecs can export information through frames using side-data or other means. For example, some MPEG based codecs export motion vectors through the export_mvs flag in the codec flags2 option.
The filter accepts the following option:
blockโ display block partition structure using the luma plane.mvโ set motion vectors to visualize. Available flags formvare:pfโ forward predicted MVs of P-framesbfโ forward predicted MVs of B-framesbbโ backward predicted MVs of B-frames
qpโ display quantization parameters using the chroma planes.mv_type,mvtโ set motion vectors type to visualize. Includes MVs from all frames unless specified byframe_typeoption. Available flags formv_typeare:fpโ forward predicted MVsbpโ backward predicted MVs
frame_type,ftโ set frame type to visualize motion vectors of. Available flags forframe_typeare:ifโ intra-coded frames (I-frames)pfโ predicted frames (P-frames)bfโ bi-directionally predicted frames (B-frames)
โจ Examples
- Visualize forward predicted MVs of all frames using
ffplay:
ffplay -flags2 +export_mvs input.mp4 -vf codecview=mv_type=fp
- Visualize multi-directionals MVs of P and B-Frames using
ffplay:
ffplay -flags2 +export_mvs input.mp4 -vf codecview=mv=pf+bf+bb
๐ธ colorbalance
Modify intensity of primary colors (red, green and blue) of input frames. Color grading era ๐ ๐จ
The filter allows an input frame to be adjusted in the shadows, midtones or highlights regions for the red-cyan, green-magenta or blue-yellow balance.
A positive adjustment value shifts the balance towards the primary color, a negative value towards the complementary color.
The filter accepts the following options:
rs,gs,bsโ adjust red, green and blue shadows (darkest pixels).rm,gm,bmโ adjust red, green and blue midtones (medium pixels).rh,gh,bhโ adjust red, green and blue highlights (brightest pixels). Allowed ranges for options are[-1.0, 1.0]. Defaults are0.plโ preserve lightness when changing color balance. Default is disabled.
โจ Examples
- Add red color cast to shadows:
colorbalance=rs=.3
๐ฌ Commands
This filter supports the all above options as commands.
๐ง colorcontrast
Adjust color contrast between RGB components.
The filter accepts the following options:
rcโ set the red-cyan contrast. Defaults is0.0. Allowed range is from-1.0to1.0.gmโ set the green-magenta contrast. Defaults is0.0. Allowed range is from-1.0to1.0.byโ set the blue-yellow contrast. Defaults is0.0. Allowed range is from-1.0to1.0.rcw,gmw,bywโ set the weight of eachrc,gm,byoption value. Default value is0.0. Allowed range is from0.0to1.0. If all weights are0.0filtering is disabled.plโ set the amount of preserving lightness. Default value is0.0. Allowed range is from0.0to1.0.
๐ฌ Commands
This filter supports the all above options as commands.
๐ colorcorrect
Adjust color white balance selectively for blacks and whites. This filter operates in YUV colorspace. Bestie it's literally a white-balance slider for your shadows and highlights, obsessed ๐ซถ
The filter accepts the following options:
rlโ set the red shadow spot. Allowed range is from-1.0to1.0. Default value is0.blโ set the blue shadow spot. Allowed range is from-1.0to1.0. Default value is0.rhโ set the red highlight spot. Allowed range is from-1.0to1.0. Default value is0.bhโ set the blue highlight spot. Allowed range is from-1.0to1.0. Default value is0.saturationโ set the amount of saturation. Allowed range is from-3.0to3.0. Default value is1.analyzeโ if set to anything other thanmanualit will analyze every frame and use derived parameters for filtering output frame. Possible values are:manualaverageminmaxmedianDefault value is"manual".
๐ฌ Commands
This filter supports the all above options as commands.
colorchannelmixer
Okay so this one is literally the color remix station ๐ It takes your video frames and re-mixes the color channels by hand โ as in, you get to say "hey, how much of the blue channel should leak into my red output?" and it justโฆ does it. Iconic.
Technically: this filter modifies a color channel by adding the values associated to the other channels of the same pixels. So if the value you're modifying is red, the output value is gonna be:
<red>=<red>*<rr> + <blue>*<rb> + <green>*<rg> + <alpha>*<ra>
The filter accepts the following options:
rr,rg,rb,raโ adjust contribution of input red, green, blue and alpha channels for output red channel. Default is1forrr, and0forrg,rbandra.gr,gg,gb,gaโ adjust contribution of input red, green, blue and alpha channels for output green channel. Default is1forgg, and0forgr,gbandga.br,bg,bb,baโ adjust contribution of input red, green, blue and alpha channels for output blue channel. Default is1forbb, and0forbr,bgandba.ar,ag,ab,aaโ adjust contribution of input red, green, blue and alpha channels for output alpha channel. Default is1foraa, and0forar,agandab.
Allowed ranges for options are [-2.0, 2.0]. ๐ซถ
pcโ set preserve color mode. The accepted values are:noneโ disable color preserving, this is default.lumโ preserve luminance.maxโ preserve max value of RGB triplet.avgโ preserve average value of RGB triplet.sumโ preserve sum value of RGB triplet.nrmโ preserve normalized value of RGB triplet.pwrโ preserve power value of RGB triplet.
paโ set the preserve color amount when changing colors. Allowed range is from[0.0, 1.0]. Default is0.0, thus disabled.
Examples
- Convert source to grayscale ๐ฉถ
colorchannelmixer=.3:.4:.3:0:.3:.4:.3:0:.3:.4:.3
- Simulate sepia tones (vintage filter energy, no cap) ๐ท
colorchannelmixer=.393:.769:.189:0:.349:.686:.168:0:.272:.534:.131
Commands
This filter supports the all above options as commands. โจ
colordetect
This one's the detective of the filter family ๐ต๏ธโโ๏ธ It analyzes the video frames to figure out the effective value range and alpha mode. Literally doing vibe checks on your pixels.
The filter accepts the following options:
modeโ set of properties to detect. Unavailable properties, such as alpha mode for an input image without an alpha channel, will be ignored automatically.
Accepts a combination of the following flags:
color_rangeโ detect if the source contains luma pixels outside the limited (MPEG) range, which indicates that this is a full range YUV source.alpha_modeโ detect if the source contains color values above the alpha channel, which indicates that the alpha channel is independent (straight), rather than premultiplied. Also detects if the alpha plane is fully opaque or not.allโ enable detection of all of the above properties. This is the default.
colorize
Overlay a solid color on the video stream. It's giving "put a filter on it" but make it literal ๐
The filter accepts the following options:
hueโ set the color hue. Allowed range is from0to360. Default value is0.saturationโ set the color saturation. Allowed range is from0to1. Default value is0.5.lightnessโ set the color lightness. Allowed range is from0to1. Default value is0.5.mixโ set the mix of source lightness. By default is set to1.0. Allowed range is from0.0to1.0.
Commands
This filter supports the all above options as commands. ๐
colorkey
RGB colorspace color keying. Think green screen, but make it chroma-key chic ๐ This filter operates on 8-bit RGB format frames by setting the alpha component of each pixel which falls within the similarity radius of the key color to 0. The alpha value for pixels outside the similarity radius depends on the value of the blend option.
The filter accepts the following options:
colorโ set the color for which alpha will be set to0(full transparency). See"Color"section in the ffmpeg-utils manual. Default is"black".similarityโ set the radius from the key color within which other colors also have full transparency. The computed distance is related to the unit fractional distance in 3D space between the RGB values of the key color and the pixel's color. Range is0.01to1.0.0.01matches within a very small radius around the exact key color, while1.0matches everything. Default is0.01.blendโ set how the alpha value for pixels that fall outside the similarity radius is computed.0.0makes pixels either fully transparent or fully opaque. Higher values result in semi-transparent pixels, with greater transparency the more similar the pixel color is to the key color. Range is0.0to1.0. Default is0.0.
Examples
- Make every green pixel in the input image transparent:
ffmpeg -i input.png -vf colorkey=green out.png
- Overlay a greenscreen-video on top of a static background image. (the classic, the icon ๐)
ffmpeg -i background.png -i video.mp4 -filter_complex "[1:v]colorkey=0x3BBD1E:0.3:0.2[ckout];[0:v][ckout]overlay[out]" -map "[out]" output.flv
Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value. โ ๏ธ
colorhold
Remove all color information for all RGB colors except for certain one. So likeโฆ everything goes neutral gray except your main character color, which gets to keep its whole personality ๐ธ
The filter accepts the following options:
colorโ the color which will not be replaced with neutral gray.similarityโ similarity percentage with the above color.0.01matches only the exact key color, while1.0matches everything.blendโ blend percentage.0.0makes pixels fully gray. Higher values result in more preserved color.
Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value. โ ๏ธ
colorlevels
Adjust video input frames using levels. Levels! Like the thing in Photoshop your artsy friend is obsessed with ๐จ
The filter accepts the following options:
rimin,gimin,bimin,aiminโ adjust red, green, blue and alpha input black point. Allowed ranges for options are[-1.0, 1.0]. Defaults are0.rimax,gimax,bimax,aimaxโ adjust red, green, blue and alpha input white point. Allowed ranges for options are[-1.0, 1.0]. Defaults are1.
Input levels are used to lighten highlights (bright tones), darken shadows (dark tones), change the balance of bright and dark tones.
romin,gomin,bomin,aominโ adjust red, green, blue and alpha output black point. Allowed ranges for options are[0, 1.0]. Defaults are0.romax,gomax,bomax,aomaxโ adjust red, green, blue and alpha output white point. Allowed ranges for options are[0, 1.0]. Defaults are1.
Output levels allows manual selection of a constrained output level range.
preserveโ set preserve color mode. The accepted values are:noneโ disable color preserving, this is default.lumโ preserve luminance.maxโ preserve max value of RGB triplet.avgโ preserve average value of RGB triplet.sumโ preserve sum value of RGB triplet.nrmโ preserve normalized value of RGB triplet.pwrโ preserve power value of RGB triplet.
Examples
- Make video output darker:
colorlevels=rimin=0.058:gimin=0.058:bimin=0.058
- Increase contrast:
colorlevels=rimin=0.039:gimin=0.039:bimin=0.039:rimax=0.96:gimax=0.96:bimax=0.96
- Make video output lighter:
colorlevels=rimax=0.902:gimax=0.902:bimax=0.902
- Increase brightness:
colorlevels=romin=0.5:gomin=0.5:bomin=0.5
Commands
This filter supports the all above options as commands. ๐
colormap
Apply custom color maps to video stream. This one's a whole group project, bestie โ it needs three input video streams. First stream is video stream that is going to be filtered out. Second and third video stream specify color patches for source color to target color mapping. It's giving "match this color to that color" and honestly? Slay.
The filter accepts the following options:
patch_sizeโ set the source and target video stream patch size in pixels.nb_patchesโ set the max number of used patches from source and target video stream. Default value is number of patches available in additional video streams. Max allowed number of patches is64.typeโ set the adjustments used for target colors. Can be"relative"or"absolute". Defaults is"absolute".kernelโ set the kernel used to measure color differences between mapped colors.
The accepted values are:
euclideanweuclidean
Default is "euclidean".
colormatrix
Convert color matrix. Simple, clean, does exactly what it says on the tin โจ
The filter accepts the following options:
src,dstโ specify the source and destination color matrix. Both values must be specified.
The accepted values are:
bt709โ BT.709fccโ FCCbt601โ BT.601bt470โ BT.470bt470bgโ BT.470BGsmpte170mโ SMPTE-170Msmpte240mโ SMPTE-240Mbt2020โ BT.2020
For example to convert from BT.601 to SMPTE-240M, use the command:
colormatrix=bt601:smpte240m
colorspace
Convert colorspace, transfer characteristics or color primaries. Input video needs to have an even size โ no cap, that's a requirement, don't fight it ๐ฆ
The filter accepts the following options:
allโ specify all color properties at once.
The accepted values are:
bt470mโ BT.470Mbt470bgโ BT.470BGbt601-6-525โ BT.601-6 525bt601-6-625โ BT.601-6 625bt709โ BT.709smpte170mโ SMPTE-170Msmpte240mโ SMPTE-240Mbt2020โ BT.2020
spaceโ specify output colorspace.
The accepted values are:
bt709โ BT.709fccโ FCCbt470bgโ BT.470BG or BT.601-6 625smpte170mโ SMPTE-170M or BT.601-6 525smpte240mโ SMPTE-240Mycgcoโ YCgCobt2020nclโ BT.2020 with non-constant luminance
trcโ specify output transfer characteristics.
The accepted values are:
bt709โ BT.709bt470mโ BT.470Mbt470bgโ BT.470BGgamma22โ Constant gamma of 2.2gamma28โ Constant gamma of 2.8smpte170mโ SMPTE-170M, BT.601-6 625 or BT.601-6 525smpte240mโ SMPTE-240Msrgbโ SRGB
iec61966-2-1โ literallyiec61966-2-1, no notes, that's the whole vibe ๐iec61966-2-4โiec61966-2-4, again, exactly what it says on the tinxvyccโxvycc(iykyk)bt2020-10โ BT.2020 but for 10-bits content โจbt2020-12โ BT.2020 for 12-bits content โจ
primaries
Set the output color primaries, bestie. The accepted values are giving:
bt709โ BT.709bt470mโ BT.470Mbt470bgโ BT.470BG or BT.601-6 625smpte170mโ SMPTE-170M or BT.601-6 525smpte240mโ SMPTE-240Mfilmโ film ๐๏ธsmpte431โ SMPTE-431smpte432โ SMPTE-432bt2020โ BT.2020jedec-p22โ JEDEC P22 phosphors
range
Set the output color range. Accepted values:
tvโ TV (restricted) rangempegโ MPEG (restricted) rangepcโ PC (full) rangejpegโ JPEG (full) range
format
Set the output color format. Accepted values, and yes there are a lot, we love a thorough queen ๐ :
yuv420pโ YUV 4:2:0 planar 8-bitsyuv420p10โ YUV 4:2:0 planar 10-bitsyuv420p12โ YUV 4:2:0 planar 12-bitsyuv422pโ YUV 4:2:2 planar 8-bitsyuv422p10โ YUV 4:2:2 planar 10-bitsyuv422p12โ YUV 4:2:2 planar 12-bitsyuv444pโ YUV 4:4:4 planar 8-bitsyuv444p10โ YUV 4:4:4 planar 10-bitsyuv444p12โ YUV 4:4:4 planar 12-bits
fast
Do a fast conversion โ it skips gamma/primary correction. Sounds cute, right? It uses significantly less CPU, but it will be mathematically incorrect ๐ญ. If you want output that's compatible with whatever the colormatrix filter produces, use fast=1.
dither
Set the dithering mode. Accepted values:
noneโ no ditheringfsbโ Floyd-Steinberg dithering
wpadapt
Whitepoint adaptation mode. Accepted values:
bradfordโ Bradford whitepoint adaptationvonkriesโ von Kries whitepoint adaptationidentityโ identity whitepoint adaptation (i.e. no whitepoint adaptation)
clipgamut
Controls how to clip out-of-gamut colors that show up as a result of colorspace conversion. Accepted values:
noneโ no clipping of out of gamut colors.rgbโ clips the RGB values to the[0, 1]range when building the gamma transfer LUTs.
iall
Override all input properties at once. Same accepted values as all.
ispace
Override the input colorspace. Same accepted values as space.
iprimaries
Override the input color primaries. Same accepted values as primaries.
itrc
Override the input transfer characteristics. Same accepted values as trc.
irange
Override the input color range. Same accepted values as range.
Okay so here's the lore ๐ซถ: the filter converts the transfer characteristics, color space and color primaries to whatever user values you specified. The output value, if you didn't specify it, gets set to a default value based on the all property. And if that property also isn't specified? The filter will log an error, periodt. The output color range and format default to the same value as the input color range and format. The input transfer characteristics, color space, color primaries and color range should be set on the input data โ if any of these are missing, the filter logs an error and no conversion will take place ๐.
So like, for example, to convert the input to SMPTE-240M, use:
colorspace=smpte240m
colortemperature ๐ก๏ธ
Adjust the color temperature in video to simulate variations in ambient color temperature. Cozy vibes only.
This filter accepts the following options:
temperatureโ sets the temperature in Kelvin. Allowed range is from1000to40000. Default value is6500K.mixโ set mixing with filtered output. Allowed range is from0to1. Default value is1.plโ set the amount of preserving lightness. Allowed range is from0to1. Default value is0.
Commands
This filter supports the same commands as options. Slay ๐ .
convolution ๐
Apply convolution of 3x3, 5x5, 7x7 or horizontal/vertical up to 49 elements. It's giving math class but make it iconic.
The filter accepts the following options:
0m1m2m3mโ set the matrix for each plane. The matrix is a sequence of 9, 25 or 49 signed integers in square mode, and from 1 to 49 odd number of signed integers in row mode.0rdiv1rdiv2rdiv3rdivโ set the multiplier for the calculated value for each plane. If unset or0, it will be1/sumof all matrix elements.0bias1bias2bias3biasโ set the bias for each plane. This value is added to the result of the multiplication. Useful for making the overall image brighter or darker. Default is0.0.0mode1mode2mode3modeโ set the matrix mode for each plane. Can besquare,roworcolumn. Default issquare.
Commands
This filter supports all the above options as commands. Obsessed.
Examples
- Apply sharpen:
convolution="0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0"
- Apply blur:
convolution="1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1/9:1/9:1/9:1/9"
- Apply edge enhance:
convolution="0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:5:1:1:1:0:128:128:128"
- Apply edge detect:
convolution="0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:5:5:5:1:0:128:128:128"
- Apply laplacian edge detector which includes diagonals:
convolution="1 1 1 1 -8 1 1 1 1:1 1 1 1 -8 1 1 1 1:1 1 1 1 -8 1 1 1 1:1 1 1 1 -8 1 1 1 1:5:5:5:1:0:128:128:0"
- Apply emboss:
convolution="-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2"
convolve โจ
Apply 2D convolution of the video stream in the frequency domain, using the second stream as the impulse. Fancy, I know.
The filter accepts the following options:
planesโ set which planes to process.impulseโ set which impulse video frames will be processed, can befirstorall. Default isall.
The convolve filter also supports the framesync options. Bestie behaviour fr fr ๐ซถ.
copy ๐
Copy the input video source unchanged to the output. Mainly useful for testing purposes โ it's the "no thoughts, head empty" filter and honestly? Respect.
coreimage ๐
Video filtering on GPU using Apple's CoreImage API on OSX. A whole aesthetic.
Hardware acceleration is based on an OpenGL context โ usually that means it's processed by video hardware. But software-based OpenGL implementations exist too, which means there's no guarantee of hardware processing ๐ญ. It depends on the respective OSX.
There are many filters and image generators provided by Apple that come with a large variety of options. The filter has to be referenced by its name along with its options.
The coreimage filter accepts the following options:
list_filtersโ list all available filters and generators along with all their respective options, plus the possible minimum and maximum values along with the default values.
list_filters=true
filterโ specify all filters by their respective name and options. Uselist_filtersto determine all valid filter names and options. Numerical options are specified by a float value and are automatically clamped to their respective value range. Vector and color options have to be specified by a list of space separated float values. Character escaping has to be done. A special option namedefaultis available to use default options for a filter.
It is required to specify either default or at least one of the filter options. All omitted options are used with their default values. The syntax of the filter string is as follows:
filter=<NAME>@<OPTION>=<VALUE>[@<OPTION>=<VALUE>][@...][#<NAME>@<OPTION>=<VALUE>[@<OPTION>=<VALUE>][@...]][#...]
output_rectโ specify a rectangle where the output of the filter chain is copied into the input image. It's given by a list of space separated float values:
output_rect=x\ y\ width\ height
If not given, the output rectangle equals the dimensions of the input image. The output rectangle is automatically cropped at the borders of the input image. Negative values are valid for each component. ๐
output_rect=25\ 25\ 100\ 100
Several filters can be chained for successive processing without GPU-HOST transfers, which allows for fast processing of complex filter chains. Currently, only filters with zero (generators) or exactly one (filters) input image and one output image are supported. Also, transition filters are not yet usable as intended.
Some filters generate output images with additional padding depending on the respective filter kernel. The padding is automatically removed to ensure the filter output has the same size as the input image. Clean.
For image generators, the size of the output image is determined by the previous output image of the filter chain or the input image of the whole filterchain, respectively. The generators do not use the pixel information of this image to generate their output. However, the generated output is blended onto this image, resulting in partial or complete coverage of the output image.
The coreimagesrc video source can be used for generating input images which are directly fed into the filter chain. By using it, providing input images by another video source or an input video is not required. Convenient much? ๐
Examples
- List all filters available:
coreimage=list_filters=true
- Use the CIBoxBlur filter with default options to blur an image:
coreimage=filter=CIBoxBlur@default
- Use a filter chain with CISepiaTone at default values and CIVignetteEffect with its center at 100x100 and a radius of 50 pixels:
coreimage=filter=CIBoxBlur@default#CIVignetteEffect@inputCenter=100\ 100@inputRadius=50
- Use
nullsrcand CIQRCodeGenerator to create a QR code for the FFmpeg homepage, given as a complete and escaped command-line for Apple's standard bash shell:
ffmpeg -f lavfi -i nullsrc=s=100x100,coreimage=filter=CIQRCodeGenerator@inputMessage=https\\\\\://FFmpeg.org/@inputCorrectionLevel=H -frames:v 1 QRCode.png
corr ๐
Obtain the correlation between two input videos. This filter takes two input videos, so bring a friend ๐ซถ.
Both input videos have to match in resolution and pixel format for this filter to actually work, bestie โ no exceptions. And it assumes both inputs have the same number of frames, which get compared one by one. ๐ซถ
The per-component, average, min and max correlation it figures out gets printed through the logging system.
The filter also stashes the calculated correlation of each frame in the frame metadata.
It also supports the framesync options, iykyk.
In the example below, the input file main.mpg being processed gets compared with the reference file ref.mpg:
ffmpeg -i main.mpg -i ref.mpg -lavfi corr -f null -
cover_rect
Cover a rectangular object ๐
It accepts the following options:
coverโ filepath of the optional cover image. Heads up: it needs to be inyuv420.modeโ set the covering mode. It accepts the following values:coverโ cover it by the supplied imageblurโ cover it by interpolating the surrounding pixels
Default value is blur.
Examples
- Cover a rectangular object by the supplied image of a given video using
ffmpeg:
ffmpeg -i file.ts -vf find_rect=newref.pgm,cover_rect=cover.jpg:mode=cover new.mkv
crop
Crop the input video to given dimensions. Classic, iconic, still serving. โ๏ธ
It accepts the following parameters:
w,out_wโ the width of the output video. It defaults toiw. This expression is evaluated only once during the filter configuration, or when theworout_wcommand is sent.h,out_hโ the height of the output video. It defaults toih. Same deal: this expression is evaluated only once during filter configuration, or when thehorout_hcommand is sent.xโ the horizontal position, in the input video, of the left edge of the output video. It defaults to(in_w-out_w)/2. This expression is evaluated per-frame.yโ the vertical position, in the input video, of the top edge of the output video. It defaults to(in_h-out_h)/2. This one's evaluated per-frame too.keep_aspectโ if set to1, it forces the output display aspect ratio to be the same as the input, by changing the output sample aspect ratio. It defaults to0.exactโ enable exact cropping. If enabled, subsampled videos get cropped at the exactwidth/height/x/yas specified and will not be rounded to the nearest smaller value. It defaults to0.
The out_w, out_h, x, y parameters are expressions containing the following constants:
x,yโ the computed values for x and y. They're evaluated for each new frame.in_w,in_hโ the input width and height.iw,ihโ these are the same asin_wandin_h.out_w,out_hโ the output (cropped) width and height.ow,ohโ these are the same asout_wandout_h.aโ same asiw/ihsarโ input sample aspect ratiodarโ input display aspect ratio, it's the same as(iw / ih) * sarhsub,vsubโ horizontal and vertical chroma subsample values. For example, for the pixel formatyuv422p,hsubis2andvsubis1.nโ the number of the input frame, starting from0.posโ the position in the file of the input frame,NANif unknown; deprecated, do not use ๐tโ the timestamp expressed in seconds. It'sNANif the input timestamp is unknown.
Now the dependency tea โ: the expression for out_w may depend on the value of out_h, and the expression for out_h may depend on out_w โ but they cannot depend on x and y, because x and y are evaluated after out_w and out_h. Order matters, no cap.
The x and y parameters specify the expressions for the position of the top-left corner of the output (non-cropped) area, and they're evaluated for each frame. If the evaluated value isn't valid, it gets approximated to the nearest valid value. Close enough is genuinely fine here.
The expression for x may depend on y, and the expression for y may depend on x. Mutual, your honor. ๐ซถ
Examples
- Crop area with size
100x100at position(12,34):
crop=100:100:12:34
Using named options, the example above becomes:
crop=w=100:h=100:x=12:y=34
- Crop the central input area with size
100x100:
crop=100:100
- Crop the central input area with size 2/3 of the input video:
crop=2/3*in_w:2/3*in_h
- Crop the input video central square:
crop=out_w=in_h
crop=in_h
- Delimit the rectangle with the top-left corner placed at position
100:100and the right-bottom corner corresponding to the right-bottom corner of the input image:
crop=in_w-100:in_h-100:100:100
- Crop 10 pixels from the left and right borders, and 20 pixels from the top and bottom borders:
crop=in_w-2*10:in_h-2*20
- Keep only the bottom right quarter of the input image:
crop=in_w/2:in_h/2:in_w/2:in_h/2
- Crop height for getting Greek harmony:
crop=in_w:1/PHI*in_w
- Apply trembling effect:
crop=in_w/2:in_h/2:(in_w-out_w)/2+((in_w-out_w)/2)*sin(n/10):(in_h-out_h)/2 +((in_h-out_h)/2)*sin(n/7)
- Apply erratic camera effect depending on timestamp:
crop=in_w/2:in_h/2:(in_w-out_w)/2+((in_w-out_w)/2)*sin(t*10):(in_h-out_h)/2 +((in_h-out_h)/2)*sin(t*13)
- Set
xdepending on the value ofy:
crop=in_w/2:in_h/2:y:10+10*sin(n/10)
Commands
This filter supports the following commands:
w,out_wh,out_hxy
These set the width/height of the output video and the horizontal/vertical position in the input video. The command accepts the same syntax as the corresponding option.
If the specified expression isn't valid, it just stays at its current value. No crash, no drama, we love a graceful non-update. โจ
cropdetect
Auto-detect the crop size. It does the math so you don't have to. ๐ง โจ
It calculates the necessary cropping parameters and prints the recommended parameters via the logging system. The detected dimensions correspond to the non-black or video area of the input video, depending on mode.
It accepts the following parameters:
modeโ depending on the mode, crop detection is based on either the mere black value of surrounding pixels, or a combination of motion vectors and edge pixels.blackโ detect black pixels surrounding the playing video. For fine control use optionlimit.mvedgesโ detect the playing video by the motion vectors inside the video, and scanning for edge pixels typically forming the border of a playing video.
limitโ set a higher black value threshold, which can be optionally specified from nothing (0) to everything (255for 8-bit based formats). Any intensity value greater than the set value is considered non-black. It defaults to24. You can also specify a value between0.0and1.0, which will be scaled depending on the bitdepth of the pixel format.roundโ the value which the width/height should be divisible by. It defaults to16. The offset is automatically adjusted to center the video. Use2to get only even dimensions (needed for 4:2:2 video).16is best when encoding to most video codecs.skipโ set the number of initial frames for which evaluation is skipped. Default is2. Range is0toINT_MAX.reset_count,resetโ set the counter that determines after how many framescropdetectwill reset the previously detected largest video area and start over to detect the current optimal crop area. Default value is0.
This can be useful when channel logos distort the video area. 0 indicates 'never reset', and returns the largest area encountered during playback.
mv_thresholdโ set motion in pixel units as threshold for motion detection. It defaults to8.low,highโ set the low and high threshold values used by the Canny thresholding algorithm.
The high threshold selects the "strong" edge pixels, which are then connected through 8-connectivity with the "weak" edge pixels selected by the low threshold.
low and high threshold values must be chosen in the range [0,1], and low should be lesser or equal to high. Respect the ordering, bestie.
Default value for low is 5/255, and default value for high is 15/255.
Examples
- Find video area surrounded by black borders:
ffmpeg -i file.mp4 -vf cropdetect,metadata=mode=print -f null -
- Find an embedded video area, generate motion vectors beforehand:
ffmpeg -i file.mp4 -vf mestimate,cropdetect=mode=mvedges,metadata=mode=print -f null -
- Find an embedded video area, use motion vectors from decoder:
ffmpeg -flags2 +export_mvs -i file.mp4 -vf cropdetect=mode=mvedges,metadata=mode=print -f null -
Commands
This filter supports the following commands:
limitโ the command accepts the same syntax as the corresponding option. If the specified expression isn't valid, it's kept at its current value.
cue
Delay video filtering until a given wallclock timestamp. Main character energy: it waits. โฐ
The filter first passes on preroll amount of frames, then it buffers at most buffer amount of frames and waits for the cue. After reaching the cue it forwards the buffered frames and also any subsequent frames coming in on its input.
The filter can be used to synchronize the output of multiple ffmpeg processes for realtime output devices like decklink. By putting the delay in the filtering chain and pre-buffering frames, the process can pass on data to output almost immediately after the target wallclock timestamp is reached.
Perfect frame accuracy cannot be guaranteed, but the result is good enough for some use cases. It's giving "close enough bestie". ๐ญ
cueโ the cue timestamp expressed in a UNIX timestamp in microseconds. Default is0.prerollโ the duration of content to pass on as preroll, expressed in seconds. Default is0.bufferโ the maximum duration of content to buffer before waiting for the cue, expressed in seconds. Default is0.
curves
Apply color adjustments using curves. This one is so pretty, wait till you see it. ๐
This filter is similar to the Adobe Photoshop and GIMP curves tools. Each component (red, green and blue) has its values defined by N key points tied from each other using a smooth curve. The x-axis represents the pixel values from the input frame, and the y-axis the new pixel values to be set for the output frame.
By default, a component curve is defined by the two points (0;0) and (1;1). This creates a straight line where each original pixel value is "adjusted" to its own value, which means no change to the image. Identity curve, zero notes, slay. ๐
Okay so this filter lets you redefine those two points and add some more โ yes bestie, you get to draw your own curve โจ A brand new curve gets defined so it passes smoothly through all your new coordinates. Two rules though, no cap: the new defined points have to be strictly increasing over the x-axis, and their x and y values must be in the [0;1] interval. The curve itself is formed using a natural or monotonic cubic spline interpolation, depending on the interp option (default: "natural"). The "natural" spline produces a smoother curve in general, while the monotonic ("pchip") spline guarantees the transitions between the specified points are monotonic. And if the computed curves happen to go outside the vector spaces? The values get clipped accordingly. ๐
The filter accepts the following options:
presetโ pick one of the available color presets ๐ This option can be used in addition to ther,g,bparameters; in that case, the later options take priority over the preset values. Available presets are:nonecolor_negativecross_processdarkerincrease_contrastlighterlinear_contrastmedium_contrastnegativestrong_contrastvintage
Default is "none".
master,mโ set the master key points. These points define a second pass mapping. It's sometimes called a "luminance" or "value" mapping. You can use it withr,g,borallsince it acts like a post-processing LUT. ๐red,rโ set the key points for the red component.green,gโ set the key points for the green component.blue,bโ set the key points for the blue component.allโ set the key points for all components (not including master). Can be used in addition to the other key points component options. In that case, the unset component(s) will fallback on thisallsetting.psfileโ specify a Photoshop curves file (".acv") to import the settings from.plotโ save Gnuplot script of the curves in specified file.interpโ specify the kind of interpolation. Available algorithms are:naturalโ Natural cubic spline using a piece-wise cubic polynomial that is twice continuously differentiable.pchipโ Monotonic cubic spline using a piecewise cubic Hermite interpolating polynomial (PCHIP).
To avoid some filtergraph syntax conflicts, each key points list needs to be defined using the following syntax: "x0/y0 x1/y1 x2/y2 ...". ikyk fr fr ๐ซถ
Commands
This filter supports same commands as options.
Examples
- Increase slightly the middle level of blue:
curves=blue='0/0 0.5/0.58 1/1'
- Vintage effect:
curves=r='0/0.11 .42/.51 1/0.95':g='0/0 0.50/0.48 1/1':b='0/0.22 .49/.44 1/0.8'
Here we obtain the following coordinates for each component:
- red
"(0;0.11) (0.42;0.51) (1;0.95)" - green
"(0;0) (0.50;0.48) (1;1)" - blue
"(0;0.22) (0.49;0.44) (1;0.80)"
- The previous example can also be achieved with the associated built-in preset:
curves=preset=vintage
- Or simply:
curves=vintage
- Use a Photoshop preset and redefine the points of the green component:
curves=psfile='MyCurvesPresets/purple.acv':green='0/0 0.45/0.53 1/1'
- Check out the curves of the
"cross_process"profile usingffmpegandgnuplot:
ffmpeg -f lavfi -i color -vf curves=cross_process:plot=/tmp/curves.plt -frames:v 1 -f null -
gnuplot -p /tmp/curves.plt
datascope
Video data analysis filter. ๐
This filter shows hexadecimal pixel values of part of video. It's giving microscope energy.
The filter accepts the following options:
size,sโ set output video size.xโ set x offset from where to pick pixels.yโ set y offset from where to pick pixels.modeโ set scope mode, can be one of the following:monoโ draw hexadecimal pixel values with white color on black background.colorโ draw hexadecimal pixel values with input video pixel color on black background.color2โ draw hexadecimal pixel values on color background picked from input video, the text color is picked in such a way so it's always visible. ๐
axisโ draw rows and columns numbers on left and top of video.opacityโ set background opacity.formatโ set display number format. Can be"hex", or"dec". Default is"hex".componentsโ set pixel components to display. By default all pixel components are displayed.
Commands
This filter supports same commands as options excluding the size option.
dblur
Apply Directional blur filter. ๐ฌ๏ธ
The filter accepts the following options:
angleโ set angle of directional blur. Default is45.radiusโ set radius of directional blur. Default is5.planesโ set which planes to filter. By default all planes are filtered.
Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
dctdnoiz
Denoise frames using 2D DCT (frequency domain filtering). ๐ง
This filter is not designed for real time. Not me warning you twice ๐
The filter accepts the following options:
sigma,sโ set the noise sigma constant.
This sigma defines a hard threshold of "3 * sigma"; every DCT coefficient (absolute value) below this threshold will be dropped.
If you need a more advanced filtering, see expr.
Default is 0.
overlapโ set number overlapping pixels for each block. Since the filter can be slow, you may want to reduce this value โ at the cost of a less effective filter and the risk of various artefacts. ๐ญ
If the overlapping value doesn't permit processing the whole input width or height, a warning will be displayed and according borders won't be denoised.
Default value is blocksize-1, which is the best possible setting.
expr,eโ set the coefficient factor expression.
For each coefficient of a DCT block, this expression will be evaluated as a multiplier value for the coefficient.
If this option is set, the sigma option will be ignored.
The absolute value of the coefficient can be accessed through the c variable.
nโ set the blocksize using the number of bits."1<<n"defines the blocksize, which is the width and height of the processed blocks.
The default value is 3 (8x8) and can be raised to 4 for a blocksize of 16x16. Note that changing this setting has huge consequences on the speed processing. Also, a larger block size does not necessarily mean a better de-noising.
Examples
- Apply a denoise with a sigma of
4.5:
dctdnoiz=4.5
- The same operation can be achieved using the expression system:
dctdnoiz=e='gte(c, 4.5*3)'
- Violent denoise using a block size of
"16x16":
dctdnoiz=15:n=4
deband
Remove banding artifacts from input video. It works by replacing banded pixels with the average value of referenced pixels. slay ๐
The filter accepts the following options:
1thr,2thr,3thr,4thrโ set banding detection threshold for each plane. Default is0.02. Valid range is0.00003to0.5. If the difference between current pixel and reference pixel is less than threshold, it will be considered as banded.range,rโ banding detection range in pixels. Default is16. If positive, a random number in range 0 to set value will be used. If negative, exact absolute value will be used. The range defines square of four pixels around current pixel.direction,dโ set direction in radians from which four pixels will be compared. If positive, a random direction from 0 to set direction will be picked. If negative, exact absolute value will be picked. For example direction0,-PIor-2*PIradians will pick only pixels on same row and-PI/2will pick only pixels on same column.blur,bโ if enabled, current pixel is compared with average value of all four surrounding pixels. The default is enabled. If disabled, current pixel is compared with all four surrounding pixels โ and the pixel is considered banded if only all four differences with surrounding pixels are less than threshold.coupling,cโ if enabled, current pixel is changed if and only if all pixel components are banded, e.g. banding detection threshold is triggered for all color components. The default is disabled.
Commands
This filter supports the all above options as commands.
deblock
Remove blocking artifacts from input video. ๐งฑโจ
The filter accepts the following options:
filterโ set filter type, can beweakorstrong. Default isstrong. This controls what kind of deblocking is applied.blockโ set size of block, allowed range is from4to512. Default is8.alpha,beta,gamma,deltaโ set blocking detection thresholds. Allowed range is0to1. Defaults are:0.098foralphaand0.05for the rest. Using a higher threshold gives more deblocking strength. Settingalphacontrols threshold detection at the exact edge of the block. The remaining options control threshold detection near the edge โ each one for below/above or left/right. Setting any of those to0disables deblocking.planesโ set planes to filter. Default is to filter all available planes.
Examples
- Deblock using weak filter and block size of 4 pixels.
deblock=filter=weak:block=4
- Deblock using strong filter, block size of 4 pixels and custom thresholds for deblocking more edges.
deblock=filter=strong:block=4:alpha=0.12:beta=0.07:gamma=0.06:delta=0.05
- Similar as above, but filter only first plane.
deblock=filter=strong:block=4:alpha=0.12:beta=0.07:gamma=0.06:delta=0.05:planes=1
- Similar as above, but filter only second and third plane.
deblock=filter=strong:block=4:alpha=0.12:beta=0.07:gamma=0.06:delta=0.05:planes=6
Commands
This filter supports the all above options as commands.
decimate
Drop duplicated frames at regular intervals. ๐๏ธ bye bestie
The filter accepts the following options:
cycleโ set the number of frames from which one will be dropped. Setting this to N means one frame in every batch of N frames will be dropped. Default is5.dupthreshโ this is your duplicate-detection threshold, bestie. if the difference metric for a frame comes in at or below this number, the filter's like "yeah that's a dupe" and calls it. default is1.1โจscthreshโ scene change threshold, iykyk. default is15๐blockx,blockyโ the size of the x-axis and y-axis blocks used during metric calculations. bigger blocks = better noise suppression but worse detection of small movements โ classic tradeoff, no cap. must be a power of two. default is32๐ppsrcโ marks the main input as a pre-processed input and activates the clean source input stream. the whole point: you can pre-process the input with various filters to help the metrics calculation while keeping the frame selection lossless. when set to1, the first stream is the pre-processed input and the second stream is the clean source from where the kept frames are chosen. default is0๐ฆchromaโ sets whether or not chroma is considered in the metric calculations. default is1๐ธmixedโ sets whether or not the input only partially contains content to be decimated. default is"false". if you enable it, the video output stream will be in variable frame rate ๐
๐ง deconvolve
applies a 2D deconvolution of the video stream in the frequency domain, using the second stream as the impulse. fancy math hours ๐
the filter accepts the following options:
planesโ set which planes to process.impulseโ set which impulse video frames will be processed. can befirstorall. default isall.noiseโ set the noise used when doing divisions. default is0.0000001. genuinely useful when width and height are not the same and not a power of 2, or if the stream prior to convolving had noise ๐ซถ
the deconvolve filter also supports the framesync options.
๐ dedot
reduces cross-luminance (that's the dot-crawl, bestie) and cross-color (the rainbows ๐) from video. iconic little cleanup crew.
it accepts the following options:
mโ set the mode of operation. can be a combination ofdotcrawlfor cross-luminance reduction and/orrainbowsfor cross-color reduction.ltโ set the spatial luma threshold. lower values increase reduction of cross-luminance.tlโ set the tolerance for temporal luma. higher values increase reduction of cross-luminance.tcโ set the tolerance for chroma temporal variation. higher values increase reduction of cross-color.ctโ set the temporal chroma threshold. lower values increase reduction of cross-color.
โญ deflate
applies the deflate effect to the video.
this filter replaces the pixel with the local (3x3) average, taking into account only values lower than the pixel. it's giving "shrink the bright bits" energy.
it accepts the following options:
threshold0,threshold1,threshold2,threshold3โ limit the maximum change for each plane. default is65535. if0, that plane will remain unchanged ๐
โจ Commands
this filter supports all of the above options as commands. slay.
๐ธ deflicker
removes temporal frame luminance variations โ the annoying brightness flicker, gone.
it accepts the following options:
size,sโ set the moving-average filter size in frames. default is5. allowed range is2-129.mode,mโ set the averaging mode for smoothing those temporal luminance variations.
the available values are:
amโ arithmetic meangmโ geometric meanhmโ harmonic meanqmโ quadratic meancmโ cubic meanpmโ power meanmedianโ median
bypassโ do not actually modify the frame. useful when you only want the metadata ๐ซถ
๐ deinterlace_d3d12
deinterlaces the input video using D3D12 hardware-accelerated video processing. gpu goes brrr.
this filter uses the DirectX 12 Video Processor to perform deinterlacing on the GPU, supporting both simple bob and driver-defined advanced (motion-adaptive) algorithms. it requires the input to be in d3d12 hardware pixel format.
the filter automatically queries the hardware for the required number of temporal reference frames (if needed) and manages a frame queue to supply them. considerate queen behavior ๐
it accepts the following options:
methodโ the deinterlacing method. accepts one of the following values:defaultโ select the best deinterlacing method available on the hardware. if the driver supportscustom, that method is used; otherwise it falls back tobob. this is the default.bobโ bob deinterlacing. each field is independently scaled to full frame height. simple and fast, but may produce visible bob artifacts on moving content ๐customโ driver-defined advanced deinterlacing. the exact algorithm is hardware-specific and typically employs motion-adaptive techniques with temporal reference frames for higher quality.
the default value is default.
modeโ specify the interlacing mode. accepts one of the following values:frameโ send one frame for each frame. the output frame rate equals the input frame rate. this is the default.fieldโ send one frame for each field. the output frame rate is double the input frame rate.
the default value is frame.
deintโ specify which frames to deinterlace. accepts one of the following values:allโ deinterlace all frames. this is the default.interlacedโ only deinterlace frames marked as interlaced; progressive frames are passed through unchanged.
the default value is all.
๐ฌ Examples
- deinterlace an interlaced video using software decoding and the best available hardware deinterlacing method:
ffmpeg -init_hw_device d3d12va=d3d12 -filter_hw_device d3d12 -i input.ts \
-vf "format=nv12,hwupload,deinterlace_d3d12=method=default,hwdownload,format=nv12" \
-c:v libx264 -crf 18 output.mp4
- deinterlace at field rate (double the frame rate) using bob method with hardware decoding (full
d3d12pipeline):
ffmpeg -hwaccel d3d12va -hwaccel_output_format d3d12 -i input.ts \
-vf "deinterlace_d3d12=method=bob:mode=field" \
-c:v h264_d3d12va output.mp4
- deinterlace only interlaced frames, passing progressive frames through:
ffmpeg -init_hw_device d3d12va=d3d12 -filter_hw_device d3d12 -i input.ts \
-vf "format=nv12,hwupload,deinterlace_d3d12=deint=interlaced,hwdownload,format=nv12" \
-c:v libx264 -crf 18 output.mp4
๐ฆ dejudder
removes judder produced by partially interlaced telecined content.
judder can be introduced, for instance, by the pullup filter. if the original source was partially telecined content, then the output of "pullup,dejudder" will have a variable frame rate. may change the recorded frame rate of the container. aside from that change, this filter will not affect constant frame rate video. periodt.
the option available in this filter is:
cycleโ specify the length of the window over which the judder repeats.
accepts any integer greater than 1. useful values are:
4โ if the original was telecined from 24 to 30 fps (Film to NTSC).5โ if the original was telecined from 25 to 30 fps (PAL to NTSC).20โ if a mixture of the two.
the default is 4 โจ
๐ delogo
suppresses a TV station logo by a simple interpolation of the surrounding pixels. just set a rectangle covering the logo and watch it disappear โ and sometimes watch something even uglier appear, your mileage may vary ๐ญ
it accepts the following parameters:
x,yโ specify the top left corner coordinates of the logo. they must be specified.w,hโ specify the width and height of the logo to clear. they must be specified.showโ when set to1, a green rectangle is drawn on the screen to simplify finding the rightx,y,w, andhparameters. the default value is0.
the rectangle is drawn on the outermost pixels which will be (partly) replaced with interpolated values. the values of the next pixels immediately outside this rectangle in each direction will be used to compute the interpolated pixel values inside the rectangle. highkey clever ๐ง
๐ Examples
- set a rectangle covering the area with top left corner coordinates
0,0and size100x77:
delogo=x=0:y=0:w=100:h=77
๐ derain
removes the rain in the input image/video by applying derain methods based on convolutional neural networks. yes bestie, we're doing ML in our video filter. supported models:
- Recurrent Squeeze-and-Excitation Context Aggregation Net (RESCAN). see
http://openaccess.thecvf.com/content_ECCV_2018/papers/Xia_Li_Recurrent_Squeeze-and-Excitation_Context_ECCV_2018_paper.pdf.
training as well as model generation scripts are provided in the repository at https://github.com/XueweiMeng/derain_filter.git. ๐ซถ
the filter accepts the following options:
filter_typeโ specify which filter to use. accepts the following values:derainโ derain filter. to conduct a derain filter, you need to use a derain model.dehazeโ dehaze filter. to conduct a dehaze filter, you need to use a dehaze model.
default value is derain.
dnn_backendโ specify which DNN backend to use for model loading and execution. accepts the following values:tensorflowโ TensorFlow backend. to enable this backend you need to install the TensorFlow for C library (seehttps://www.tensorflow.org/install/lang_c) and configure FFmpeg with--enable-libtensorflow
modelโ set the path to the model file specifying the network architecture and its parameters. note that different backends use different file formats. TensorFlow can load files for only its format. ๐
to get full functionality (such as async execution), please use the dnn_processing filter instead.
โญ deshake
attempts to fix small changes in horizontal and/or vertical shift. this filter helps remove camera shake from hand-holding a camera, bumping a tripod, moving on a vehicle, etc. shaky-cam girlies rise ๐
the filter accepts the following options:
x,y,w,hโ specify a rectangular area where to limit the search for motion vectors. if desired, the search for motion vectors can be limited to a rectangular area of the frame defined by its top left corner, width and height. these parameters have the same meaning as thedrawboxfilter, which can be used to visualise the position of the bounding box.
this is useful when simultaneous movement of subjects within the frame might be confused for camera motion by the motion vector search. iykyk ๐
If any or all of x, y, w and h are set to -1, the whole frame gets used ๐ โ which is lowkey the move, because then you can set the later options without having to spell out the bounding box for the motion vector search. Default? Search the whole frame. periodt.
rx,ryโ the max extent of movement in the x and y directions, range0-64pixels. Default16. ๐edgeโ tells the filter how to generate pixels to fill the blanks at the edge of the frame. The values you can pick:blank,0โ fill zeroes at blank locationsoriginal,1โ original image at blank locationsclamp,2โ extruded edge value at blank locationsmirror,3โ mirrored edge at blank locations
Default value is mirror. ๐ช
blocksizeโ the blocksize used for motion search. Range4-128pixels, default8. โจcontrastโ the contrast threshold for blocks, bestie. Only blocks with more than the specified contrast (that's the difference between the darkest and the lightest pixels) get considered at all. Range1-255, default125. ๐searchโ the search strategy. Available values:exhaustive,0โ set exhaustive searchless,1โ set less exhaustive search.
Default value is exhaustive. ๐
filenameโ if you set this, a detailed log of the motion search gets written to the file you name. ๐
despill ๐ง
Removes the unwanted contamination of foreground colors that happens because of reflected color from a greenscreen or bluescreen. iconic cleanup behavior, honestly.
This filter accepts the following options:
typeโ sets what type of despill you're using.mixโ sets how the spillmap is going to be generated.expandโ sets how much to get rid of the still-remaining spill.redโ controls the amount of red in the spill area.greenโ controls the amount of green in the spill area. Should be-1for greenscreen. ๐blueโ controls the amount of blue in the spill area. Should be-1for bluescreen. ๐brightnessโ controls brightness of the spill area while preserving colors.alphaโ modify alpha from the generated spillmap.
Commands ๐
This filter supports the all above options as commands.
detelecine ๐
Applies an exact inverse of the telecine operation. It requires a predefined pattern, specified with the pattern option, and that pattern must be the same one you passed to the telecine filter. no cap, they have to match.
This filter accepts the following options:
first_fieldtop,tโ top field firstbottom,bโ bottom field first
The default value is "top". โญ
patternโ a string of numbers representing the pulldown pattern you want to apply. The default value is23. ๐ฅstart_frameโ a number representing the position of the first frame with respect to the telecine pattern. Use this if the stream is cut. The default value is0. โ๏ธ
dilation ๐ธ
Applies a dilation effect to the video. Basically this filter replaces the pixel with the local (3x3) maximum. main character pixel energy.
It accepts the following options:
threshold0,threshold1,threshold2,threshold3โ limit the maximum change for each plane, default is65535. If it's0, that plane will remain unchanged. ๐coordinatesโ a flag that specifies which pixel to refer to. Default is255, i.e. all eight pixels are used.
The flags map to the local 3x3 coordinates like this:
1 2 3
4 5
6 7 8
Commands ๐
This filter supports the all above options as commands.
displace ๐
Displaces pixels as indicated by the second and third input streams.
It takes three input streams and outputs one stream. The first input is the source, and the second and third inputs are displacement maps.
The second input specifies how much to displace pixels along the x-axis, while the third input specifies how much to displace pixels along the y-axis. If one of the displacement map streams terminates, the last frame from that displacement map will be used. ๐ซถ
Note that once they're generated, displacement maps can be reused over and over again. obsessed with the efficiency honestly.
A description of the accepted options follows.
edgeโ sets the displace behavior for pixels that are out of range. Available values:blankโ missing pixels are replaced by black pixels.smearโ adjacent pixels will spread out to replace missing pixels.wrapโ out of range pixels are wrapped so they point to pixels of the other side.mirrorโ out of range pixels will be replaced with mirrored pixels.
Default is smear. โจ
Examples ๐
- Add a ripple effect to an rgb input of video size hd720:
ffmpeg -i INPUT -f lavfi -i nullsrc=s=hd720,lutrgb=128:128:128 -f lavfi -i nullsrc=s=hd720,geq='r=128+30*sin(2*PI*X/400+T):g=128+30*sin(2*PI*X/400+T):b=128+30*sin(2*PI*X/400+T)' -lavfi '[0][1][2]displace' OUTPUT
- Add a wave effect to an rgb input of video size hd720:
ffmpeg -i INPUT -f lavfi -i nullsrc=hd720,geq='r=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T)):g=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T)):b=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T))' -lavfi '[1]split[x][y],[0][x][y]displace' OUTPUT
dnn_classify ๐ง
Does classification with deep neural networks, based on bounding boxes. slay.
The filter accepts the following options:
dnn_backendโ specify which DNN backend to use for model loading and execution. This option accepts onlyopenvinoright now; tensorflow backends will be added later.modelโ set the path to the model file specifying network architecture and its parameters. Note that different backends use different file formats.inputโ set the input name of the dnn network.outputโ set the output name of the dnn network.confidenceโ set the confidence threshold (default:0.5).labelsโ set the path to the label file specifying the mapping between label id and name. Each label name is written on one line; tailing spaces and empty lines are skipped. The first line is the name of label id0, the second line is the name of label id1, etc. The label id is considered as the name if the label file isn't provided.backend_configsโ set the configs to be passed into the backend.
For the tensorflow backend, you can set its configs with sess_config options โ please use tools/python/tf_sess_config.py to get the configs for your system.
dnn_detect ๐
Does object detection with deep neural networks. detective mode activated.
The filter accepts the following options:
dnn_backendโ specify which DNN backend to use for model loading and execution. This option accepts onlyopenvinoright now; tensorflow backends will be added later.modelโ set the path to the model file specifying network architecture and its parameters. Note that different backends use different file formats.inputโ set the input name of the dnn network.outputโ set the output name of the dnn network.confidenceโ set the confidence threshold (default:0.5).labelsโ set the path to the label file specifying the mapping between label id and name. Each label name is written on one line; tailing spaces and empty lines are skipped. The first line is the name of label id0(usually it's'background'), and the second line is the name of label id1, etc. The label id is considered as the name if the label file isn't provided.backend_configsโ set the configs to be passed into the backend. To use async execution, setasync(default:set). Roll back to sync execution if the backend doesn't support async. ๐ญ
dnn_processing ๐ฆ
Does image processing with deep neural networks. It works together with another filter which converts the pixel format of the Frame to whatever the dnn network requires.
The filter accepts the following options:
dnn_backendโ specify which DNN backend to use for model loading and execution. This option accepts the following values:tensorflowโ TensorFlow backend. To enable this backend you need to install the TensorFlow for C library (seehttps://www.tensorflow.org/install/lang_c) and configure FFmpeg with--enable-libtensorflow. ๐ฅopenvinoโ OpenVINO backend. To enable this backend you need to build and install the OpenVINO for C library (seehttps://github.com/openvinotoolkit/openvino/blob/master/build-instruction.md) and configure FFmpeg with--enable-libopenvino(--extra-cflags=-I... --extra-ldflags=-L...might be needed if the header files and libraries aren't installed into the system path). โจtorchโ Libtorch backend. To enable this backend you need to build and install the Libtorch for C++ library. Please download the cxx11 ABI version (seehttps://pytorch.org/get-started/locally) and configure FFmpeg with--enable-libtorch --extra-cflags=-I/libtorch_root/libtorch/include --extra-cflags=-I/libtorch_root/libtorch/include/torch/csrc/api/include --extra-ldflags=-L/libtorch_root/libtorch/lib/. ๐
modelโ set the path to the model file specifying network architecture and its parameters. Note that different backends use different file formats. TensorFlow, OpenVINO and Libtorch backends can load files for only their own format.inputโ set the input name of the dnn network.outputโ set the output name of the dnn network.backend_configsโ set the configs to be passed into the backend. To use async execution, setasync(default:set). Roll back to sync execution if the backend doesn't support async.
For the tensorflow backend, you can set its configs with sess_config options โ please use tools/python/tf_sess_config.py to get the configs of the TensorFlow backend for your system.
Examples ๐
- Remove rain in an rgb24 frame with
can.pb(see thederainfilter):
./ffmpeg -i rain.jpg -vf format=rgb24,dnn_processing=dnn_backend=tensorflow:model=can.pb:input=x:output=y derain.jpg
- Handle the Y channel with
srcnn.pb(see thesrfilter) for a frame with yuv420p (planar YUV formats supported):
./ffmpeg -i 480p.jpg -vf format=yuv420p,scale=w=iw*2:h=ih*2,dnn_processing=dnn_backend=tensorflow:model=srcnn.pb:input=x:output=y -y srcnn.jpg
- Handle the Y channel with
espcn.pb(see thesrfilter), which changes frame size, for format yuv420p (planar YUV formats supported). Please usetools/python/tf_sess_config.pyto get the configs of the TensorFlow backend for your system.
./ffmpeg -i 480p.jpg -vf format=yuv420p,dnn_processing=dnn_backend=tensorflow:model=espcn.pb:input=x:output=y:backend_configs=sess_config=0x10022805320e09cdccccccccccec3f20012a01303801 -y tmp.espcn.jpg
๐ drawbox
Draws a colored box right on top of the input image. Simple as that, bestie.
It accepts the following parameters:
x,yโ the expressions that say where the top left corner of the box sits. Defaults to0.width,w,height,hโ the expressions for the width and height of the box; if they're0they get interpreted as the input width and height. Defaults to0.color,cโ the color of the box you're writing. For the general syntax of this option, check the "Color" section in theffmpeg-utilsmanual. And listen โ if you use the special valueinvert, the box edge color becomes the same as the video with inverted luma. Cute, right?thickness,tโ the expression that sets the thickness of the box edge. A value offillgives you a filled box (yes, the whole thing). Default value is3.
See below for the list of accepted constants.
replaceโ only applicable if the input has alpha. With value1, the pixels of the painted box overwrite the video's color and alpha pixels. Default is0, which composites the box onto the input, leaving the video's alpha intact. ๐ซถ
The parameters for x, y, w and h and t are expressions containing the following constants:
darโ the input display aspect ratio, it's the same as(w / h) * sar.hsub,vsubโ horizontal and vertical chroma subsample values. For example for the pixel formatyuv422phsubis2andvsubis1.in_h,ih,in_w,iwโ the input width and height.sarโ the input sample aspect ratio.x,yโ the x and y offset coordinates where the box is drawn.w,hโ the width and height of the drawn box.box_sourceโ box source can be set asside_data_detection_bboxesif you want to use box data in detection bboxes of side data.
If box_source is set, the x, y, width and height will be ignored and still use box data in detection bboxes of side data. So please do not use this parameter if you were not sure about the box source. ๐
tโ the thickness of the drawn box.
These constants allow the x, y, w, h and t expressions to refer to each other, so you may for example specify y=x/dar or h=w/dar. Iconic mutual-reference behavior, honestly.
โจ Examples
- Draw a black box around the edge of the input image:
drawbox
- Draw a box with color red and an opacity of 50%:
drawbox=10:20:200:60:red@0.5
The previous example can be specified as:
drawbox=x=10:y=20:w=200:h=60:color=red@0.5
- Fill the box with pink color:
drawbox=x=10:y=10:w=100:h=100:color=pink@0.5:t=fill
- Draw a 2-pixel red 2.40:1 mask:
drawbox=x=-t:y=0.5*(ih-iw/2.4)-t:w=iw+t*2:h=iw/2.4+t*2:t=2:c=red
๐ Commands
This filter supports the same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value. No drama, it just vibes where it is. ๐ธ
๐ drawgraph
Draws a graph using input video metadata. Yes, your metadata goes on a little graph. Main character energy for real.
It accepts the following parameters:
m1โ set 1st frame metadata key from which metadata values will be used to draw a graph.fg1โ set 1st foreground color expression.m2โ set 2nd frame metadata key from which metadata values will be used to draw a graph.fg2โ set 2nd foreground color expression.m3โ set 3rd frame metadata key from which metadata values will be used to draw a graph.fg3โ set 3rd foreground color expression.m4โ set 4th frame metadata key from which metadata values will be used to draw a graph.fg4โ set 4th foreground color expression.minโ set minimal value of metadata value.maxโ set maximal value of metadata value.bgโ set graph background color. Default iswhite.modeโ set graph mode.
Available values for mode is:
bardotline
Default is line.
slideโ set slide mode.
Available values for slide is:
frameโ draw new frame when right border is reached.replaceโ replace old columns with new ones.scrollโ scroll from right to left.rscrollโ scroll from left to right.pictureโ draw single picture.
Default is frame.
sizeโ set size of graph video. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. The default value is900x256.rate,rโ set the output frame rate. Default value is25.
The foreground color expressions can use the following variables:
MINโ minimal value of metadata value.MAXโ maximal value of metadata value.VALโ current metadata key value.
The color is defined as 0xAABBGGRR. Note the byte order, bestie, don't get it twisted ๐.
๐ง Example using metadata from signalstats filter:
signalstats,drawgraph=lavfi.signalstats.YAVG:min=0:max=255
๐ง Example using metadata from ebur128 filter:
ebur128=metadata=1,adrawgraph=lavfi.r128.M:min=-120:max=5
๐ฒ drawgrid
Draws a grid on the input image. Grids are lowkey underrated, and this one slays.
It accepts the following parameters:
x,yโ the expressions which specify the coordinates of some point of grid intersection (meant to configure offset). Both default to0.width,w,height,hโ the expressions which specify the width and height of the grid cell; if0they are interpreted as the input width and height, respectively, minusthickness, so the image gets framed. Default to0.color,cโ specify the color of the grid. For the general syntax of this option, check the "Color" section in theffmpeg-utilsmanual. If the special valueinvertis used, the grid color is the same as the video with inverted luma.thickness,tโ the expression which sets the thickness of the grid line. Default value is1.
See below for the list of accepted constants.
replaceโ applicable if the input has alpha. With1the pixels of the painted grid will overwrite the video's color and alpha pixels. Default is0, which composites the grid onto the input, leaving the video's alpha intact.
The parameters for x, y, w and h and t are expressions containing the following constants:
darโ the input display aspect ratio, it is the same as(w / h) * sar.hsub,vsubโ horizontal and vertical chroma subsample values. For example for the pixel formatyuv422phsubis2andvsubis1.in_h,ih,in_w,iwโ the input grid cell width and height.sarโ the input sample aspect ratio.x,yโ the x and y coordinates of some point of grid intersection (meant to configure offset).w,hโ the width and height of the drawn cell.tโ the thickness of the drawn cell.
These constants allow the x, y, w, h and t expressions to refer to each other, so you may for example specify y=x/dar or h=w/dar.
๐ Examples
- Draw a grid with cell 100x100 pixels, thickness 2 pixels, with color red and an opacity of 50%:
drawgrid=width=100:height=100:thickness=2:color=red@0.5
- Draw a white 3x3 grid with an opacity of 50%:
drawgrid=w=iw/3:h=ih/3:t=2:c=white@0.5
๐ Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value. Same energy as drawbox, periodt. ๐
โ๏ธ drawtext
Draws a text string โ or text from a specified file โ on top of a video, using the libfreetype library. This is the one everybody's obsessed with, ngl.
To enable compilation of this filter, you need to configure FFmpeg with --enable-libfreetype and --enable-libharfbuzz. To enable default font fallback and the font option you need to configure FFmpeg with --enable-libfontconfig. To enable the text_shaping option, you need to configure FFmpeg with --enable-libfribidi.
๐ซถ Heads up bestie: those are build-time configure flags. If your FFmpeg wasn't built with them, this filter (or parts of it) just won't be there โ no cap.
๐ธ Syntax
It accepts the following parameters:
boxโ used to draw a box around text using thebackground color. The value must be either1(enable) or0(disable). The default value ofboxis0.boxborderwโ set the width of the border to be drawn around the box usingboxcolor. The value must be specified using one of the following formats:boxborderw=10โ set the width of all the borders to10boxborderw=10|20โ set the width of the top and bottom borders to10and the width of the left and right borders to20boxborderw=10|20|30โ set the width of the top border to10, the width of the bottom border to30and the width of the left and right borders to20boxborderw=10|20|30|40โ set the borders width to10(top),20(right),30(bottom),40(left)
The default value of boxborderw is 0.
boxcolorโ the color to be used for drawing box around text. For the syntax of this option, check the "Color" section in theffmpeg-utilsmanual.
The default value of boxcolor is white.
line_spacingโ set the line spacing in pixels. The default value ofline_spacingis0.text_alignโ set the vertical and horizontal alignment of the text with respect to the box boundaries. The value is a combination of flags, one for the vertical alignment (T=top,M=middle,B=bottom) and one for the horizontal alignment (L=left,C=center,R=right). Please note that tab characters are only supported with the left horizontal alignment. ๐y_alignโ specify what theyvalue is referred to. Possible values are:textโ the top of the highest glyph of the first text line is placed atybaselineโ the baseline of the first text line is placed atyfontโ the baseline of the first text line is placed atyplus the ascent (in pixels) defined in the font metrics
The default value of y_align is text for backward compatibility.
borderwโ set the width of the border to be drawn around the text usingbordercolor. The default value ofborderwis0.bordercolorโ set the color to be used for drawing border around text. For the syntax of this option, check the "Color" section in theffmpeg-utilsmanual.
The default value of bordercolor is black.
expansionโ select how the text is expanded. Can be eithernone,strftime(deprecated) ornormal(default). See thedrawtext_expansion, Text expansion section below for details.
๐ strftime is deprecated, bestie. It still exists, but it's giving legacy vibes.
basetimeโ set a start time for the count. Value is in microseconds. Only applied in the deprecatedstrftimeexpansion mode. To emulate in normal expansion mode use theptsfunction, supplying the start time (in seconds) as the second argument.fix_boundsโ if it'strue, the filter checks your text coords and fixes them so nothing gets clipped off the edge. considerate king behavior ๐fontcolorโ the colour used to draw the text. for the syntax, go peek at the "Color" section in theffmpeg-utilsmanual. default is"black".fontcolor_exprโ a string that gets expanded exactly the same way astextto obtain a dynamic fontcolor value. by default this option is empty and just... not processed. but when you set it, it overrides thefontcoloroption. so it's lowkey the main character ๐fontโ the font family used for drawing the text. default isSans.fontfile โ ok wait, that'sfontfile: the actual font file used for drawing text. the path must be included (yes, the whole path, not just the name bestie). this parameter is mandatory if the fontconfig support is disabled.alphaโ draw the text with alpha blending. value can be a number between0.0and1.0. the expression accepts the same variablesx,yas well. default value is1. please seefontcolor_expr(it's giving sibling energy).fontsizeโ the font size for drawing text. default is16.text_shapingโ if set to1, it attempts to shape the text before drawing it (like reversing the order of right-to-left text and joining Arabic characters). otherwise it just draws the text exactly as given. by default1(if supported). โจft_load_flagsโ the flags used for loading the fonts. these map to the corresponding flags supported by libfreetype, and they're a combination of these values:defaultno_scaleno_hintingrenderno_bitmapvertical_layoutforce_autohintcrop_bitmappedanticignore_global_advance_widthno_recurseignore_transformmonochromelinear_designno_autohint
default value is "default". for more info, consult the documentation for the FT_LOAD_* libfreetype flags. ngl, that's a lot of flags, but we respect her ๐
shadowcolorโ the colour used for drawing a shadow behind the drawn text. for the syntax, check the "Color" section in theffmpeg-utilsmanual. default is"black".boxwโ set the width of the box drawn around the text. by default,boxwis computed automatically to match the text width. ๐boxhโ set the height of the box drawn around the text. by default,boxhis computed automatically to match the text height.shadowx,shadowyโ the x and y offsets for the text shadow position relative to the position of the text. they can be positive or negative. default for both is"0".start_numberโ the starting frame number for then/frame_numvariable. default is"0".tabsizeโ the size, in number of spaces, used for rendering a tab. default is4.timecodeโ set the initial timecode representation in"hh:mm:ss[:;.]ff"format. can be used with or without thetextparameter. thetimecode_rateoption must be specified. โฐtimecode_rate,rate,rโ set the timecode frame rate (timecode only). the value gets rounded to the nearest integer. minimum value is"1". drop-frame timecode is supported for frame rates30&60.tc24hmaxโ if set to1, the output of thetimecodeoption wraps around at 24 hours. default is0(disabled).textโ the text string to be drawn. it must be a sequence of UTF-8 encoded characters. this parameter is mandatory if no file is specified with thetextfileparameter.textfileโ a text file containing the text to be drawn. the text must be a sequence of UTF-8 encoded characters.
this parameter is mandatory if no text string is specified with the text parameter.
if both text and textfile are specified, an error is thrown. pick a lane, babe ๐ญ
text_sourceโ set the text source toside_data_detection_bboxesif you want to use text data in the detection bboxes of side data.
if the text source is set, text and textfile get ignored and it still uses the text data in the detection bboxes of side data. so please don't use this parameter if you're not sure about the text source. > seriously, don't mess with it if you don't know what it does ๐ซถ
reloadโ thetextfilegets reloaded at the specified frame interval. be sure to updatetextfileatomically, or it may be read partially, or even fail outright. range is0toINT_MAX. default is0.x,yโ the expressions that specify the offsets where text is drawn within the video frame. they're relative to the top/left border of the output image. default value ofxandyis"0". see below for the list of accepted constants and functions ๐
๐ธ the constants & functions for x and y ๐ธ
the parameters for x and y are expressions containing these constants and functions:
darโ input display aspect ratio, same as(w / h) * sarhsub,vsubโ horizontal and vertical chroma subsample values. for example, for the pixel formatyuv422p,hsubis2andvsubis1.line_h,lhโ the height of each text linemain_h,h,Hโ the input heightmain_w,w,Wโ the input widthmax_glyph_a,ascentโ the maximum distance from the baseline to the highest/upper grid coordinate used to place a glyph outline point, for all the rendered glyphs. it's a positive value, because of the grid's orientation with the Y axis upwards.max_glyph_d,descentโ the maximum distance from the baseline to the lowest grid coordinate used to place a glyph outline point, for all the rendered glyphs. this one's a negative value, due to the grid's orientation with the Y axis upwards.max_glyph_hโ maximum glyph height, i.e. the maximum height for all the glyphs contained in the rendered text. it's equivalent toascent - descent.max_glyph_wโ maximum glyph width, i.e. the maximum width for all the glyphs contained in the rendered textfont_aโ the ascent size defined in the font metricsfont_dโ the descent size defined in the font metricstop_aโ the maximum ascender of the glyphs of the first text linebottom_dโ the maximum descender of the glyphs of the last text linenโ the number of the input frame, starting from0rand(min, max)โ returns a random number included between min and maxsarโ the input sample aspect ratiotโ timestamp expressed in seconds,NANif the input timestamp is unknowntext_h,thโ the height of the rendered texttext_w,twโ the width of the rendered textx,yโ the x and y offset coordinates where the text is drawn.
these parameters let the x and y expressions refer to each other, so you can for example specify y=x/dar. iconic mutual-reference moment ๐ซ
pict_typeโ a one character description of the current frame's picture type.pkt_posโ the current packet's position in the input file or stream (in bytes, from the start of the input). a value of-1indicates this info is not available.durationโ the current packet's duration, in seconds.pkt_sizeโ the current packet's size (in bytes).
๐ซ Text expansion ๐ซ
if expansion is set to "strftime", the filter recognizes sequences accepted by the strftime C function in the provided text and expands them accordingly. check the documentation of strftime. > heads up: this feature is deprecated in favor of "normal" expansion with the gmtime or localtime expansion functions. we're moving on, bestie ๐
if expansion is set to "none", the text is printed verbatim. no notes.
if expansion is set to "normal" (which is the default), this expansion mechanism is used:
the backslash character \, followed by any character, always expands to the second character.
sequences of the form %{...} get expanded. the text between the braces is a function name, possibly followed by arguments separated by :. if the arguments contain special characters or delimiters (: or }), they should be escaped.
note that they probably must also be escaped as the value for the text option in the filter argument string, and as the filter argument in the filtergraph description, and possibly also for the shell. that's up to four levels of escaping ๐ญ using a text file with the textfile option avoids these problems. huge W for text files honestly.
these are the functions available:
expr,eโ the expression evaluation result.
it must take one argument specifying the expression to evaluate, which accepts the same constants and functions as the x and y values. note that not all constants should be used โ for example the text size isn't known when evaluating the expression, so the constants text_w and text_h will have an undefined value. ๐
expr_int_format,eifโ evaluate the expression's value and output it as a formatted integer.
the first argument is the expression to evaluate, just like for the expr function. the second argument specifies the output format โ allowed values are x, X, d and u, treated exactly as in the printf function. the third parameter is optional and sets the number of positions taken by the output; it can be used to add padding with zeros from the left. โจ
gmtimeโ the time at which the filter is running, expressed in UTC. it can accept an argument: astrftimeC function format string. the format string is extended to support the variable%[1-6]N, which prints fractions of the second with optionally specified number of digits.localtimeโ the time at which the filter is running, expressed in the local time zone. it can accept an argument: astrftimeC function format string. the format string is extended to support the variable%[1-6]N, which prints fractions of the second with optionally specified number of digits.metadataโ frame metadata. takes one or two arguments.
the first argument is mandatory and specifies the metadata key.
the second argument is optional and specifies a default value, used when the metadata key is not found or is empty.
available metadata can be identified by inspecting entries starting with TAG included within each frame section printed by running ffprobe -show_frames.
string metadata generated in filters leading to the drawtext filter are also available. ๐ซถ
n,frame_numโ the frame number, starting from0.pict_typeโ a one character description of the current picture type.ptsโ the timestamp of the current frame. it can take up to three arguments.
The first argument is the format of the timestamp, and it defaults to "flt" โ that's seconds as a decimal number with microsecond accuracy. "hms" gives you a formatted [-]HH:MM:SS.mmm timestamp with millisecond accuracy. "gmtime" gives you the frame's timestamp formatted as UTC time, and "localtime" gives it to you in the local time zone. ๐
The second argument is an offset that gets added to the timestamp.
If the format is "hms", you can pass a third argument "24HH" to present the hour part of the formatted timestamp in 24h format (00-23). ๐
If the format is "localtime" or "gmtime", a third argument may be supplied: a strftime C function format string. If you don't, the default YYYY-MM-DD HH:MM:SS format is what you get. ๐
Commands
Bestie, this filter supports altering parameters via commands:
reinitโ alters existing filter parameters. The syntax for the argument is the same as for filter invocation, like:
fontsize=56:fontcolor=green:text='Hello World'
Full filter invocation with sendcmd would look like this:
sendcmd=c='56.0 drawtext reinit fontsize=56\:fontcolor=green\:text=Hello\\ World'
If the entire argument can't be parsed or applied as valid values, then the filter just continues on with its existing parameters. No drama, it just vibes with what it had. ๐
The following options are also supported as commands:
*<x>*<y>*<alpha>*<fontsize>*<fontcolor>*<boxcolor>*<bordercolor>*<shadowcolor>*<box>*<boxw>*<boxh>*<boxborderw>*<line_spacing>*<text_align>*<shadowx>*<shadowy>*<borderw>
Examples
- Draw
"Test Text"with font FreeSerif, using the default values for the optional parameters.
drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text'"
- Draw
'Test Text'with font FreeSerif of size24at positionx=100andy=50(counting from the top-left corner of the screen). The text is yellow with a red box around it, and both the text and the box have an opacity of 20%. ๐ฅ
drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text':\
x=100: y=50: fontsize=24: fontcolor=yellow@0.2: box=1: boxcolor=red@0.2"
Note that the double quotes aren't necessary if spaces aren't used within the parameter list. Periodt. โจ
- Show the text at the center of the video frame:
drawtext="fontsize=30:fontfile=FreeSerif.ttf:text='hello world':x=(w-text_w)/2:y=(h-text_h)/2"
- Show the text at a random position, switching to a new position every 30 seconds:
drawtext="fontsize=30:fontfile=FreeSerif.ttf:text='hello world':x=if(eq(mod(t\,30)\,0)\,rand(0\,(w-text_w))\,x):y=if(eq(mod(t\,30)\,0)\,rand(0\,(h-text_h))\,y)"
- Show a text line sliding from right to left in the last row of the video frame. The file
LONG_LINEis assumed to contain a single line with no newlines.
drawtext="fontsize=15:fontfile=FreeSerif.ttf:text=LONG_LINE:y=h-line_h:x=-50*t"
- Show the content of file
CREDITSoff the bottom of the frame and scroll up. ๐ฆ
drawtext="fontsize=20:fontfile=FreeSerif.ttf:textfile=CREDITS:y=h-20*t"
- Draw a single green letter
"g"at the center of the input video. The glyph baseline is placed at half screen height.
drawtext="fontsize=60:fontfile=FreeSerif.ttf:fontcolor=green:text=g:x=(w-max_glyph_w)/2:y=h/2-ascent"
- Show text for 1 second every 3 seconds:
drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:enable=lt(mod(t\,3)\,1):text='blink'"
- Use fontconfig to set the font. Note that the colons need to be escaped.
drawtext='fontfile=Linux Libertine O-40\\:style=Semibold:text=FFmpeg'
- Draw
"Test Text"with font size dependent on height of the video.
drawtext="text='Test Text': fontsize=h/30: x=(w-text_w)/2: y=(h-text_h*2)"
- Print the date of a real-time encoding (see documentation for the
strftimeC function):
drawtext='fontfile=FreeSans.ttf:text=%{localtime\:%a %b %d %Y}'
- Show text fading in and out (appearing/disappearing):
#!/bin/sh
DS=1.0 # display start
DE=10.0 # display end
FID=1.5 # fade in duration
FOD=5 # fade out duration
ffplay -f lavfi "color,drawtext=text=TEST:fontsize=50:fontfile=FreeSerif.ttf:fontcolor_expr=ff0000%{eif\\\\: clip(255*(1*between(t\, $DS + $FID\, $DE - $FOD) + ((t - $DS)/$FID)*between(t\, $DS\, $DS + $FID) + (-(t - $DE)/$FOD)*between(t\, $DE - $FOD\, $DE) )\, 0\, 255) \\\\: x\\\\: 2 }"
- Horizontally align multiple separate texts. Note that
max_glyph_aand thefontsizevalue are included in theyoffset. ๐
drawtext=fontfile=FreeSans.ttf:text=DOG:fontsize=24:x=10:y=20+24-max_glyph_a,
drawtext=fontfile=FreeSans.ttf:text=cow:fontsize=24:x=80:y=20+24-max_glyph_a
- Plot special
lavf.image2dec.source_basenamemetadata onto each frame if such metadata exists. Otherwise, plot the string"NA". Ngl, note that theimage2demuxer must have option-export_path_metadata 1for the special metadata fields to be available for filters. ๐
drawtext="fontsize=20:fontcolor=white:fontfile=FreeSans.ttf:text='%{metadata\:lavf.image2dec.source_basename\:NA}':x=10:y=10"
For more information about libfreetype, check: <http://www.freetype.org/>.
For more information about fontconfig, check: <http://freedesktop.org/software/fontconfig/fontconfig-user.html>.
For more information about libfribidi, check: <http://fribidi.org/>.
For more information about libharfbuzz, check: <https://github.com/harfbuzz/harfbuzz>.
๐จ drawvg
Draw vector graphics on top of video frames, by executing a script written in a custom language called VGS (Vector Graphics Script). It's giving "I made my own language, no big deal". ๐
The documentation for the language can be found in drawvg - Language Reference. A version of this reference with rendered examples can be found at <https://ayosec.github.io/ffmpeg-drawvg/playground/docs/langref.html>.
Graphics are rendered using <https://cairographics.org/>.
To enable compilation of this filter, you need to configure FFmpeg with --enable-cairo. ๐
Parameters
Either script or file must be set. (Yes, you need one of them. Pick your fighter.)
s,scriptโ script source to draw the graphics.fileโ path of the file to load the script source.
Pixel Formats
Since Cairo only supports RGB images, if the input video is something else (like YUV 4:2:0), before executing the script the video is converted to a format compatible with Cairo. Then you have to use either the format filter, or the -pix_fmt option, to convert it to the expected format in the output. Don't forget this step bestie, or it's gonna be a whole mess. ๐ญ
Examples
- Draw the outline of an ellipse.
ffmpeg -i input.webm \
-vf 'drawvg=ellipse (w/2) (h/2) (w/3) (h/3) stroke' \
-pix_fmt yuv420p \
output.webm
- Draw a square rotating in the middle of the frame.
The script for drawvg is in a file "draw.vgs":
translate (w/2) (h/2)
rotate t
rect -100 -100 200 200
setcolor red@0.5
fill
Then:
ffmpeg -i input.webm -vf 'drawvg=file=draw.vgs,format=yuv420p' output.webm
๐๏ธ edgedetect
Detect and draw edges. The filter uses the Canny Edge Detection algorithm. Lowkey iconic. โจ
The filter accepts the following options:
low,highโ set low and high threshold values used by the Canny thresholding algorithm.
The high threshold selects the "strong" edge pixels, which are then connected through 8-connectivity with the "weak" edge pixels selected by the low threshold. Fr fr, that's the whole vibe.
low and high threshold values must be chosen in the range [0,1], and low should be lesser or equal to high.
Default value for low is "20/255", and default value for high is "50/255".
modeโ define the drawing mode.wiresโ draw white/gray wires on black background.colormixโ mix the colors to create a paint/cartoon effect.cannyโ apply Canny edge detector on all selected planes.
Default value is wires.
planesโ select planes for filtering. By default all available planes are filtered.
Examples
- Standard edge detection with custom values for the hysteresis thresholding:
edgedetect=low=0.1:high=0.4
- Painting effect without thresholding:
edgedetect=mode=colormix:high=0
๐ elbg
Apply a posterize effect using the ELBG (Enhanced LBG) algorithm.
For each input image, the filter will compute the optimal mapping from the input to the output given the codebook length, that is the number of distinct output colors.
This filter accepts the following options.
codebook_length,lโ set codebook length. The value must be a positive integer, and represents the number of distinct output colors. Default value is256.nb_steps,nโ set the maximum number of iterations to apply for computing the optimal mapping. The higher the value, the better the result and the higher the computation time. Default value is1.seed,sโ set a random seed, must be an integer included between0andUINT32_MAX. If not specified, or if explicitly set to-1, the filter will try to use a good random seed on a best effort basis. (It tries its best, ok? ๐ซถ)pal8โ set pal8 output pixel format. This option does not work with codebook length greater than256. Default is disabled.use_alphaโ include alpha values in the quantization calculation. Allows creating palettized output images (e.g. PNG8) with multiple alpha smooth blending. ๐
๐ entropy
Measure graylevel entropy in histogram of color channels of video frames.
It accepts the following parameters:
modeโ can be eithernormalordiff. Default isnormal.
diff mode measures entropy of histogram delta values, absolute differences between neighbour histogram values.
๐ epx
Apply the EPX magnification filter which is designed for pixel art. Pixel artists, this one's for you. ๐
It accepts the following option:
nโ set the scaling dimension:2for"2xEPX",3for"3xEPX". Default is3.
โ๏ธ eq
Set brightness, contrast, saturation and approximate gamma adjustment.
The filter accepts the following options:
contrastโ set the contrast expression. The value must be a float value in range-1000.0to1000.0. The default value is"1".brightnessโ set the brightness expression. The value must be a float value in range-1.0to1.0. The default value is"0".saturationโ the saturation expression. Gotta be a float from0.0to3.0, default is"1". ๐gammaโ the gamma expression. Float in range0.1to10.0, default"1".gamma_rโ gamma expression, but make it red ๐. Float from0.1to10.0, default"1".gamma_gโ gamma expression for green. Float0.1to10.0, default"1".gamma_bโ gamma expression for blue. Float0.1to10.0, default"1".gamma_weightโ the gamma weight expression. Lowkey the glow-up protector of your highlights: it reduces the effect of a big gamma value on bright image areas so they don't get overamplified into a plain white void ๐ญ. Float from0.0to1.0.0.0turns gamma correction alllll the way down,1.0leaves it at full strength. Default is"1".evalโ tells the filter when to evaluate the brightness, contrast, saturation and gamma expressions. Takes these values:initโ evaluate the expressions once, during filter initialization or when a command is processed.frameโ evaluate the expressions for every incoming frame. โจ
Default value is init.
The expressions accept these parameters:
nโ frame count of the input frame, starting from0.posโ byte position of the corresponding packet in the input file,NANif unspecified. > heads up bestie: this one is deprecated, do not use it ๐rโ frame rate of the input video,NANif the input frame rate is unknown.tโ timestamp expressed in seconds,NANif the input timestamp is unknown.
Commands
This filter supports the following commands, no cap:
contrastโ set the contrast expression.brightnessโ set the brightness expression.saturationโ set the saturation expression.gammaโ set the gamma expression.gamma_rโ set the gamma_r expression.gamma_gโ set gamma_g expression.gamma_bโ set gamma_b expression.gamma_weightโ set gamma_weight expression.
The command accepts the same syntax as the corresponding option. And if the expression you hand it isn't valid? It just chills at its current value ๐ซถ.
erosion
Bestie this one literally erodes your video. Apply the erosion effect โ it replaces the pixel by the local 3x3 minimum. Iconic, destructive, love her ๐
It accepts the following options:
threshold0,threshold1,threshold2,threshold3โ limit the maximum change for each plane. Default is65535. If it's0, that plane stays completely unchanged.coordinatesโ a flag saying which pixels to refer to. Default is255, meaning all eight pixels get used.
The flags map to local 3x3 coordinates like this:
1 2 3
4 5
6 7 8
Commands
This filter supports all the above options as commands. ๐
estdif
Deinterlace the input video โ and yes, "estdif" stands for "Edge Slope Tracing Deinterlacing Filter", she's got a whole government name ๐ธ
Spatial only filter that uses the edge slope tracing algorithm to interpolate the missing lines. It accepts the following parameters:
modeโ the interlacing mode to adopt. Accepts:frameโ output one frame for each frame.fieldโ output one frame for each field.
Default value is "field".
parityโ the picture field parity assumed for the input interlaced video. Accepts:tffโ assume the top field is first.bffโ assume the bottom field is first.autoโ enable automatic detection of field parity.
Default value is "auto". If the interlacing is unknown or the decoder doesn't export this info, top field first gets assumed.
deintโ which frames to deinterlace. Accepts:allโ deinterlace all frames.interlacedโ only deinterlace frames marked as interlaced.
Default value is "all".
rslopeโ the search radius for edge slope tracing. Default value is1. Allowed range is1to15.redgeโ the search radius for best edge matching. Default value is2. Allowed range is0to15.ecostโ the edge cost for edge matching. Default value is2. Allowed range is0to50.mcostโ the middle cost for edge matching. Default value is1. Allowed range is0to50.dcostโ the distance cost for edge matching. Default value is1. Allowed range is0to50.interpโ the interpolation used. Default is 4-point interpolation. Accepts:2pโ two-point interpolation.4pโ four-point interpolation.6pโ six-point interpolation.
Commands
This filter supports the same commands as options. ๐
exposure
Adjust the exposure of the video stream. It's giving camera app slider energy โจ
The filter accepts the following options:
exposureโ set the exposure correction in EV. Allowed range is from-3.0to3.0EV. Default value is0EV.blackโ set the black level correction. Allowed range is from-1.0to1.0. Default value is0.
Commands
This filter supports the same commands as options.
extractplanes
Extract color channel components from the input video stream into separate grayscale video streams. One video in, a whole friend group of grayscale streams out ๐ญ๐
The filter accepts the following option:
planesโ set the plane(s) to extract.
Available values for planes are:
yuvargb
Choosing planes that aren't available in the input will result in an error. Basically you can't select "r", "g", "b" planes at the same time as "y", "u", "v" planes โ pick a lane bestie ๐ซถ
Examples
- Extract luma, u and v color channel components from the input video frame into 3 grayscale outputs:
ffmpeg -i video.avi -filter_complex 'extractplanes=y+u+v[y][u][v]' -map '[y]' y.avi -map '[u]' u.avi -map '[v]' v.avi
fade
Apply a fade-in/out effect to the input video. Main character entrance AND exit, both handled ๐
It accepts the following parameters:
type,tโ the effect type, either"in"for a fade-in or"out"for a fade-out. Default is"in".start_frame,sโ the number of the frame to start applying the fade effect at. Default is0.nb_frames,nโ how many frames the fade effect lasts. At the end of the fade-in, the output video has the same intensity as the input video. At the end of the fade-out transition, the output video is filled with the selected color. Default is25.alphaโ if set to1, fade only the alpha channel, if one exists on the input. Default value is0.start_time,stโ the timestamp (in seconds) of the frame to start applying the fade effect. If bothstart_frameandstart_timeare specified, the fade starts at whichever comes last. Default is0.duration,dโ the number of seconds the fade effect has to last. At the end of the fade-in the output video has the same intensity as the input video; at the end of the fade-out transition the output video is filled with the selected color. If bothdurationandnb_framesare specified,durationwins. Default is0(nb_framesis used by default).color,cโ the color of the fade. Default is"black".
Examples
- Fade in the first 30 frames of video:
fade=in:0:30
The command above is equivalent to:
fade=t=in:s=0:n=30
- Fade out the last 45 frames of a 200-frame video:
fade=out:155:45
fade=type=out:start_frame=155:nb_frames=45
- Fade in the first 25 frames and fade out the last 25 frames of a 1000-frame video:
fade=in:0:25, fade=out:975:25
- Make the first 5 frames yellow, then fade in from frame 5-24:
fade=in:5:20:color=yellow
- Fade in alpha over the first 25 frames of video:
fade=in:0:25:alpha=1
- Make the first 5.5 seconds black, then fade in for 0.5 seconds:
fade=t=in:st=5.5:d=0.5
feedback
Apply the feedback video filter. This one's a little mind-bender ngl ๐ฅ
This filter passes cropped input frames to the 2nd output. From there you can filter them with other video filters. After the filter receives a frame from the 2nd input, that frame is combined on top of the original frame from the 1st input and passed to the 1st output.
The typical usage is filtering only part of a frame. Sneaky, targeted, we love her ๐
The filter accepts the following options:
x,yโ set the top left crop position.w,hโ set the crop size.
Examples
- Blur only the top left rectangular part of a video frame, size
100x100, with thegblurfilter:
[in][blurin]feedback=x=0:y=0:w=100:h=100[out][blurout];[blurout]gblur=8[blurin]
- Draw a black box on the top left part of a video frame, size
100x100, with thedrawboxfilter:
[in][blurin]feedback=x=0:y=0:w=100:h=100[out][blurout];[blurout]drawbox=x=0:y=0:w=100:h=100:t=100[blurin]
- Pixelize a rectangular part of a video frame, size
100x100, with thepixelizefilter:
[in][blurin]feedback=x=320:y=240:w=100:h=100[out][blurout];[blurout]pixelize[blurin]
fftdnoiz
Denoise frames using 3D FFT (frequency domain filtering). Science girlie behaviour ๐งโจ
The filter accepts the following options:
sigmaโ set the noise sigma constant, which sets the denoising strength. Default value is1. Allowed range is from0to30. > warning bestie: using a very highsigmawith lowoverlapmay give you blocking artifacts ๐ญamountโ set the amount of denoising. By default all detected noise is reduced. Default value is1. Allowed range is from0to1.blockโ set the size of the block in pixels. Default is32, can be8to256.overlapโ set the block overlap. Default is0.5. Allowed range is from0.2to0.8.methodโ set the denoising method. Default is"wiener", can also be"hard".prevโ set the number of previous frames to use for denoising. By default it's set to0.nextโ set the number of next frames to use for denoising. By default it's set to0.planesโ set the planes which will be filtered. By default all available planes are filtered, except alpha.
fftfilt
Apply arbitrary expressions to samples in the frequency domain โ and that's where we pick this up, bestieโฆ ๐ซ
dc_Yโ tweaks the dc value (gain, bestie) of the luma plane. Integer,0to1000, default0. ๐dc_Uโ same deal but for the 1st chroma plane. Integer0to1000, default0.dc_Vโ and the 2nd chroma plane, because she deserves one too. Integer0to1000, default0.weight_Yโ sets the frequency domain weight expression for the luma plane. โจweight_Uโ frequency domain weight expression for the 1st chroma plane.weight_Vโ frequency domain weight expression for the 2nd chroma plane.evalโ decides when the expressions get evaluated. Choices are:initโ only evaluate expressions once, during filter initialization.frameโ evaluate expressions for every single incoming frame.
Default value is init. Lowkey efficient.
The filter accepts the following variables:
X,Yโ the coordinates of the current sample.W,Hโ the width and height of the image.Nโ the number of input frame, starting from0.WS,HSโ the size of FFT array for horizontal and vertical processing.
๐ Examples
- High-pass:
fftfilt=dc_Y=128:weight_Y='squish(1-(Y+X)/100)'
- Low-pass:
fftfilt=dc_Y=0:weight_Y='squish((Y+X)/100-1)'
- Sharpen:
fftfilt=dc_Y=0:weight_Y='1+squish(1-(Y+X)/100)'
- Blur:
fftfilt=dc_Y=0:weight_Y='exp(-4 * ((Y+X)/(W+H)))'
๐พ field
Extracts a single field from an interlaced image using stride arithmetic, so it doesn't waste CPU time โ efficient queen behavior honestly. The output frames are marked as non-interlaced. ๐
The filter accepts the following options:
typeโ specifies whether to extract the top field (if the value is0or"top") or the bottom field (if the value is1or"bottom").
๐ fieldhint
Makes brand-new frames by copying the top and bottom fields from surrounding frames โ and the frame numbers come from a hint file, bestie. It's giving "DIY field assembly" and we're obsessed. ๐ง
hintโ sets the file containing hints: absolute/relative frame numbers.
There must be one line for each frame in a clip. Each line must contain two numbers separated by the comma, optionally followed by "-" or "+". Numbers supplied on each line of file can not be out of [N-1,N+1] where N is current frame number for "absolute" mode or out of [-1, 1] range for "relative" mode. First number tells from which frame to pick up top field and second number tells from which frame to pick up bottom field.
If optionally followed by "+" output frame will be marked as interlaced, else if followed by "-" output frame will be marked as progressive, else it will be marked same as input frame. If optionally followed by "t" output frame will use only top field, or in case of "b" it will use only bottom field. If line starts with "#" or ";" that line is skipped. ๐ซถ
modeโ can be item"absolute"or"relative"or"pattern". Default is"absolute". The"pattern"mode is same as"relative"mode, except at last entry of file if there are more frames to process than"hint"file is seek back to start. Yes, it loops. Main character energy.
Example of first several lines of "hint" file for "relative" mode:
0,0 - # first frame
1,0 - # second frame, use third's frame top field and second's frame bottom field
1,0 - # third frame, use fourth's frame top field and third's frame bottom field
1,0 -
0,0 -
0,0 -
1,0 -
1,0 -
1,0 -
0,0 -
0,0 -
1,0 -
1,0 -
1,0 -
0,0 -
๐ฌ fieldmatch
Field matching filter for inverse telecine โ say that five times fast, I dare you. It's meant to reconstruct the progressive frames from a telecined stream. Important thing though: the filter does not drop duplicated frames, so to actually achieve a complete inverse telecine "fieldmatch" needs to be followed by a decimation filter such as decimate in the filtergraph. Don't forget your girl decimate, fr fr. ๐
The separation of the field matching and the decimation is notably motivated by the possibility of inserting a de-interlacing filter fallback between the two. If the source has mixed telecined and real interlaced content, "fieldmatch" will not be able to match fields for the interlaced parts. But these remaining combed frames will be marked as interlaced, and thus can be de-interlaced by a later filter such as yadif before decimation. Slay, graceful fallback. โจ
In addition to the various configuration options, "fieldmatch" can take an optional second stream, activated through the ppsrc option. If enabled, the frames reconstruction will be based on the fields and frames from this second stream. This allows the first input to be pre-processed in order to help the various algorithms of the filter, while keeping the output lossless (assuming the fields are matched properly). Typically, a field-aware denoiser, or brightness/contrast adjustments can help. ๐
Note that this filter uses the same algorithms as TIVTC/TFM (AviSynth project) and VIVTC/VFM (VapourSynth project). The later is a light clone of TFM from which "fieldmatch" is based on. While the semantic and usage are very close, some behaviour and options names can differ. So likeโฆ same vibe, different font. ๐
The decimate filter currently only works for constant frame rate input. If your input has mixed telecined (30fps) and progressive content with a lower framerate like 24fps use the following filterchain to produce the necessary cfr stream: "dejudder,fps=30000/1001,fieldmatch,decimate". Copy-paste her, she's iconic.
The filter accepts the following options:
orderโ specifies the assumed field order of the input stream. Available values are:autoโ auto detect parity (use FFmpeg's internal parity value).bffโ assume bottom field first.tffโ assume top field first.
Note that it is sometimes recommended not to trust the parity announced by the stream. ๐ The stream can lie, bestie.
Default value is auto.
modeโ sets the matching mode or strategy to use.pcmode is the safest in the sense that it won't risk creating jerkiness due to duplicate frames when possible, but if there are bad edits or blended fields it will end up outputting combed frames when a good match might actually exist. On the other hand,pcn_ubmode is the most risky in terms of creating jerkiness, but will almost always find a good frame if there is one. The other values are all somewhere in betweenpcandpcn_ubin terms of risking jerkiness and creating duplicate frames versus finding good matches in sections with bad edits, orphaned fields, blended fields, etc.
More details about p/c/n/u/b are available in p/c/n/u/b meaning section. (Go read it, iykyk.)
Available values are:
pcโ 2-way matching (p/c)pc_nโ 2-way matching, and trying 3rd match if still combed (p/c + n)pc_uโ 2-way matching, and trying 3rd match (same order) if still combed (p/c + u)pc_n_ubโ 2-way matching, trying 3rd match if still combed, and trying 4th/5th matches if still combed (p/c + n + u/b)pcnโ 3-way matching (p/c/n)pcn_ubโ 3-way matching, and trying 4th/5th matches if all 3 of the original matches are detected as combed (p/c/n + u/b)
The parenthesis at the end indicate the matches that would be used for that mode assuming order=tff (and field on auto or top).
In terms of speed pc mode is by far the fastest and pcn_ub is the slowest.
Default value is pc_n.
ppsrcโ marks the main input stream as a pre-processed input, and enables the secondary input stream as the clean source to pick the fields from. See the filter introduction for more details. It is similar to the clip2 feature from VFM/TFM. ๐ฆ
Default value is 0 (disabled).
fieldโ sets the field to match from. It is recommended to set this to the same value asorderunless you experience matching failures with that setting. In certain circumstances changing the field that is used to match from can have a large impact on matching performance. Available values are:autoโ automatic (same value asorder).bottomโ match from the bottom field.topโ match from the top field.
Default value is auto.
mchromaโ sets whether or not chroma is included during the match comparisons. In most cases it is recommended to leave this enabled. You should set this to0only if your clip has bad chroma problems such as heavy rainbowing or other artifacts. Setting this to0could also be used to speed things up at the cost of some accuracy. Trade-offs, babe. โ๏ธ
Default value is 1.
y0,y1โ these define an exclusion band which excludes the lines betweeny0andy1from being included in the field matching decision. An exclusion band can be used to ignore subtitles, a logo, or other things that may interfere with the matching.y0sets the starting scan line andy1sets the ending line; all lines in betweeny0andy1(includingy0andy1) will be ignored. Settingy0andy1to the same value will disable the feature.y0andy1defaults to0.scthreshโ sets the scene change detection threshold as a percentage of maximum change on the luma plane. Good values are in the"[8.0, 14.0]"range. Scene change detection is only relevant in casecombmatch=sc. The range forscthreshis"[0.0, 100.0]". ๐
Default value is 12.0.
combmatchโ when combmatch is notnone,"fieldmatch"will take into account the combed scores of matches when deciding what match to use as the final match. Available values are:noneโ no final matching based on combed scores.scโ combed scores are only used when a scene change is detected.fullโ use combed scores all the time.
Default is sc.
combdbgโ forces"fieldmatch"to calculate the combed metrics for certain matches and print them. This setting is known asmicoutin TFM/VFM vocabulary. Available values are:noneโ no forced calculation.pcnโ force p/c/n calculations.pcnubโ force p/c/n/u/b calculations.
Default value is none.
cthreshโ the area combing threshold used for combed frame detection. It basically controls how "strong" or "visible" the combing has to be before the filter goes "yep, that's combed." Bigger values = combing must be more visible to get caught, smaller values = combing can be faint and still get detected. Valid settings run from-1(literally every pixel gets flagged as combed ๐) to255(no pixel ever gets flagged as combed). Underneath it's a pixel difference value, and a good range is"[8, 12]".
Default value is 9.
chromaโ sets whether chroma gets a vote in the combed-frame decision. Only turn this off if your source has chroma problems (rainbowing, etc.) that are messing with detection while chroma is enabled. Ngl, usingchroma=0is usually more reliable, except for the case where there's chroma-only combing in the source.
Default value is 0.
blockx,blockyโ respectively set the x-axis and y-axis size of the window used during combed frame detection. It's about the size of the area where combpel pixels have to be detected as combed for a frame to be declared combed โ see thecombpeldescription for more. Possible values are any number that's a power of 2, starting at4and going up to512.
Default value is 16.
combpelโ the number of combed pixels inside any of theblockybyblockxsize blocks on the frame, for the frame to be detected as combed. So whilecthreshcontrols how "visible" the combing has to be, this one controls how much combing there has to be in any localized area (a window defined by theblockxandblockysettings) on the frame. Minimum value is0and maximum is"blocky x blockx"(at which point no frames will ever be detected as combed). In TFM/VFM vocabulary this setting is known as MI ๐
Default value is 80.
p/c/n/u/b meaning โ the lore โจ
p/c/n
We assume the following telecined stream:
Top fields: 1 2 2 3 4
Bottom fields: 1 2 3 4 4
The numbers correspond to the progressive frame the fields relate to. So here, the first two frames are progressive, the 3rd and 4th are combed, and so on.
When "fieldmatch" is configured to run a matching from bottom (field=bottom), this is how that input stream gets transformed:
Input stream:
T 1 2 2 3 4
B 1 2 3 4 4 <-- matching reference
Matches: c c n n c
Output stream:
T 1 2 3 4 4
B 1 2 3 4 4
As a result of the field matching, we can see that some frames get duplicated. So to do a complete inverse telecine you gotta rely on a decimation filter after this operation โ see for instance the decimate filter, bestie ๐ซถ
The same operation, but now matching from top fields (field=top), looks like this:
Input stream:
T 1 2 2 3 4 <-- matching reference
B 1 2 3 4 4
Matches: c c p p c
Output stream:
T 1 2 2 3 4
B 1 2 2 3 4
In these examples you can see what p, c and n mean; basically they refer to the frame and field of the opposite parity:
<p matches the field of the opposite parity in the previous frame><c matches the field of the opposite parity in the current frame><n matches the field of the opposite parity in the next frame>
u/b
The u and b matching are a lil special, in the sense that they match from the opposite parity flag. In the following examples we assume we're currently matching the 2nd frame (Top:2, bottom:2). According to the match, an x is placed above and below each matched field.
With bottom matching (field=bottom):
Match: c p n b u
x x x x x
Top 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2
Bottom 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
x x x x x
Output frames:
2 1 2 2 2
2 2 2 1 3
With top matching (field=top):
Match: c p n b u
x x x x x
Top 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2
Bottom 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
x x x x x
Output frames:
2 2 2 1 2
2 1 3 2 2
Examples
Simple IVTC of a top field first telecined stream:
fieldmatch=order=tff:combmatch=none, decimate
Advanced IVTC, with fallback on yadif for still combed frames:
fieldmatch=order=tff:combmatch=full, yadif=deint=interlaced, decimate
๐ fieldorder
Transform the field order of the input video. Serving looks, but for fields ๐
It accepts the following parameters:
orderโ the output field order. Valid values aretfffor top field first, orbfffor bottom field first.
The default value is tff.
The transformation is done by shifting the picture content up or down by one line, and filling the remaining line with appropriate picture content. This method is consistent with most broadcast field order converters.
If the input video isn't flagged as being interlaced, or it's already flagged as being of the required output field order, then this filter doesn't alter the incoming video at all. It just vibes. ๐ธ
It's super useful when converting to or from PAL DV material, which is bottom field first.
For example:
ffmpeg -i in.vob -vf "fieldorder=bff" out.dv
๐ผ๏ธ fillborders
Fill borders of the input video without changing video stream dimensions. Sometimes video has garbage at the four edges and you don't wanna crop the input just to keep the size a multiple of some number. Iconic behaviour, honestly.
This filter accepts the following options:
leftโ number of pixels to fill from the left border.rightโ number of pixels to fill from the right border.topโ number of pixels to fill from the top border.bottomโ number of pixels to fill from the bottom border.modeโ set the fill mode.
It accepts the following values:
smearโ fill pixels using outermost pixelsmirrorโ fill pixels using mirroring (half sample symmetric)fixedโ fill pixels with constant valuereflectโ fill pixels using reflecting (whole sample symmetric)wrapโ fill pixels using wrappingfadeโ fade pixels to constant valuemarginsโ fill pixels at top and bottom with weighted averages pixels near borders
Default is smear.
colorโ set color for pixels infixedorfademode. Default is black.
Commands
This filter supports the same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it's kept at its current value. No drama, no crash ๐
๐ find_rect
Find a rectangular object in the input video. Detective mode: activated ๐ต๏ธโโ๏ธ
The object to search for must be specified as a gray8 image, given with the object option.
For each possible match, a score is computed. If the score reaches the specified threshold, the object is considered found.
If the input video contains multiple instances of the object, the filter will find only one of them. (Rude, but ok.)
When an object is found, the following metadata entries are set in the matching frame:
lavfi.rect.wโ width of objectlavfi.rect.hโ height of objectlavfi.rect.xโ x position of objectlavfi.rect.yโ y position of objectlavfi.rect.scoreโ match score of the found object
It accepts the following options:
objectโ filepath of the object image, needs to be ingray8.thresholdโ detection threshold, expressed as a decimal number in the range0-1.
A threshold value of 0.01 means only exact matches, a threshold of 0.99 means almost everything matches. Choose your fighter โ๏ธ
Default value is 0.5.
mipmapsโ number of mipmaps, default is3.xmin,ymin,xmax,ymaxโ specifies the rectangle in which to search.discardโ discard frames where object is not detected. Default is disabled.
Examples
- Cover a rectangular object by the supplied image of a given video using
ffmpeg:
ffmpeg -i file.ts -vf find_rect=newref.pgm,cover_rect=cover.jpg:mode=cover new.mkv
- Find the position of an object in each frame using
ffprobeand write it to a log file:
ffprobe -f lavfi movie=test.mp4,find_rect=object=object.pgm:threshold=0.3 \
-show_entries frame=pkt_pts_time:frame_tags=lavfi.rect.x,lavfi.rect.y \
-of csv -o find_rect.csv
๐จ floodfill
Flood area with values of same pixel components with another values. Yes, it's the paint-bucket tool from MS Paint but make it Unix ๐
It accepts the following options:
xโ set pixel x coordinate.yโ set pixel y coordinate.s0โ set source #0 component value.s1โ set source #1 component value.s2โ set source #2 component value.s3โ set source #3 component value.d0โ set destination #0 component value.d1โ set destination #1 component value.d2โ set destination #2 component value.d3โ set destination #3 component value.
๐ format
Convert the input video to one of the specified pixel formats. Libavfilter will try to pick one that's suitable as input to the next filter โ it's out here doing matchmaking for your filter chain ๐ซถ
It accepts the following parameters:
pix_fmtsโ a|-separated list of pixel format names, such as"pix_fmts=yuv420p|monow|rgb24".color_spacesโ a|-separated list of color space names, such as"color_spaces=bt709|bt470bg|bt2020nc".color_rangesโ a|-separated list of color range names, such as"color_ranges=tv|pc".alpha_modesโ a|-separated list of color range names, such as"alpha_modes=straight|premultiplied". (Yep, it literally says "color range names" right there in the manpage ๐ iykyk.)
Examples
- Convert the input video to the
yuv420pformat:
format=pix_fmts=yuv420p
Convert the input video to any of the formats in the list:
format=pix_fmts=yuv420p|yuv444p|yuv410p
๐ fps
Okay so this one is the frame-rate glow-up filter ๐ โ it converts your video to a specified constant frame rate by duplicating or dropping frames as necessary. Like, it will literally clone frames or yeet them into the void to hit the number you asked for.
It accepts the following parameters:
fpsโ the desired output frame rate. Iconic behaviour: it accepts expressions containing the following constants:source_fpsโ the input's frame ratentscโ NTSC frame rate of"30000/1001"palโ PAL frame rate of25.0filmโ film frame rate of24.0ntsc_filmโ NTSC-film frame rate of"24000/1001"
The default is 25.
start_timeโ assume the first PTS should be the given value, in seconds. This allows for padding/trimming at the start of stream. By default, no assumption is made about the first frame's expected PTS, so no padding or trimming is done. For example, this could be set to0to pad the beginning with duplicates of the first frame if a video stream starts after the audio stream, or to trim any frames with a negative PTS.roundโ the timestamp (PTS) rounding method. Possible values are:zeroโ round towards 0infโ round away from 0downโ round towards -infinityupโ round towards +infinitynearโ round to nearest
The default is "near".
eof_actionโ action performed when reading the last frame. Possible values are:roundโ use same timestamp rounding method as used for other frames.passโ pass through last frame if input duration has not been reached yet.
The default is "round".
Alternatively, the options can be specified as a flat string: fps[:start_time[:round]].
See also the setpts filter ๐ซถ.
Examples
- A typical usage in order to set the fps to
25:
fps=fps=25
- Sets the fps to
24, using abbreviation and rounding method to round to nearest:
fps=fps=film:round=near
๐ฆ framepack
Pack two different video streams into a stereoscopic video, setting proper metadata on supported codecs. The two views should have the same size and framerate, and processing will stop when the shorter video ends (rude, but fair ๐ญ). Please note that you may conveniently adjust view properties with the scale and fps filters.
It accepts the following parameters:
formatโ the desired packing format. Supported values are:sbsโ the views are next to each other (default).tabโ the views are on top of each other.linesโ the views are packed by line.columnsโ the views are packed by column.frameseqโ the views are temporally interleaved.
Some examples:
# Convert left and right views into a frame-sequential video
ffmpeg -i LEFT -i RIGHT -filter_complex framepack=frameseq OUTPUT
# Convert views into a side-by-side video with the same output resolution as the input
ffmpeg -i LEFT -i RIGHT -filter_complex [0:v]scale=w=iw/2[left],[1:v]scale=w=iw/2[right],[left][right]framepack=sbs OUTPUT
โญ framerate
Change the frame rate by interpolating new video output frames from the source frames. Literally manifesting frames that never existed, main character energy โจ.
โ ๏ธ This filter is not designed to function correctly with interlaced media. If you wish to change the frame rate of interlaced media then you are required to deinterlace before this filter and re-interlace after this filter. No cap, do it in that order.
A description of the accepted options follows.
fpsโ specify the output frames per second. This option can also be specified as a value alone. The default is50.interp_startโ specify the start of a range where the output frame will be created as a linear interpolation of two frames. The range is[0-255], the default is15.interp_endโ specify the end of a range where the output frame will be created as a linear interpolation of two frames. The range is[0-255], the default is240.sceneโ specify the level at which a scene change is detected as a value between0and100to indicate a new scene; a low value reflects a low probability for the current frame to introduce a new scene, while a higher value means the current frame is more likely to be one. The default is8.2.flagsโ specify flags influencing the filter process. Available value forflagsis:scene_change_detect,scdโ enable scene change detection using the value of the optionscene. This flag is enabled by default.
๐ธ framestep
Select one frame every N-th frame. Very "I'm only responding to every fifth text" of it tbh ๐.
This filter accepts the following option:
stepโ select frame after every"step"frames. Allowed values are positive integers higher than0. Default value is1.
๐ freezedetect
Detect frozen video. It's giving "is this thing even on" ๐.
This filter logs a message and sets frame metadata when it detects that the input video has no significant change in content during a specified duration. Video freeze detection calculates the mean average absolute difference of all the components of video frames and compares it to a noise floor.
The printed times and duration are expressed in seconds. The "lavfi.freezedetect.freeze_start" metadata key is set on the first frame whose timestamp equals or exceeds the detection duration, and it contains the timestamp of the first frame of the freeze. The "lavfi.freezedetect.freeze_duration" and "lavfi.freezedetect.freeze_end" metadata keys are set on the first frame after the freeze.
The filter accepts the following options:
noise,nโ set noise tolerance. Can be specified in dB (in case"dB"is appended to the specified value) or as a difference ratio between0and1. Default is-60dB, or0.001.duration,dโ set freeze duration until notification (default is2seconds).
๐ง freezeframes
Freeze video frames. This filter freezes video frames using a frame from the 2nd input ๐ซถ.
The filter accepts the following options:
firstโ set number of first frame from which to start freeze.lastโ set number of last frame from which to end freeze.replaceโ set number of frame from 2nd input which will be used instead of replaced frames.
๐ frei0r
Apply a frei0r effect to the input video. Plugins, but make it video ๐.
To enable the compilation of this filter, you need to install the frei0r header and configure FFmpeg with --enable-frei0r.
It accepts the following parameters:
filter_nameโ the name of the frei0r effect to load. If the environment variableFREI0R_PATHis defined, the frei0r effect is searched for in each of the directories specified by the colon-separated list inFREI0R_PATH. Otherwise, the standard frei0r paths are searched, in this order:HOME/.frei0r-1/lib/,/usr/local/lib/frei0r-1/,/usr/lib/frei0r-1/.filter_paramsโ a'|'-separated list of parameters to pass to the frei0r effect.
A frei0r effect parameter can be a boolean (its value is either "y" or "n"), a double, a color (specified as R/G/B, where R, G, and B are floating point numbers between 0.0 and 1.0, inclusive) or a color description as specified in the "Color" section in the ffmpeg-utils manual, a position (specified as X/Y, where X and Y are floating point numbers) and/or a string.
The number and types of parameters depend on the loaded effect. If an effect parameter is not specified, the default value is set.
Examples
- Apply the
distort0reffect, setting the first two double parameters:
frei0r=filter_name=distort0r:filter_params=0.5|0.01
- Apply the
colordistanceeffect, taking a color as the first parameter:
frei0r=colordistance:0.2/0.3/0.4
frei0r=colordistance:violet
frei0r=colordistance:0x112233
- Apply the
perspectiveeffect, specifying the top left and top right image positions:
frei0r=perspective:0.2/0.2|0.8/0.2
For more information, see http://frei0r.dyne.org
Commands โจ
This filter supports the filter_params option as commands.
๐ fspp
Apply fast and simple postprocessing. It is a faster version of spp โก.
It splits (I)DCT into horizontal/vertical passes. Unlike the simple post-processing filter, one of them is performed once per block, not per pixel. This allows for much higher speed. Lowkey efficient queen behaviour.
The filter accepts the following options:
qualityโ set quality. This option defines the number of levels for averaging. It accepts an integer in the range4-5. Default value is4.qpโ force a constant quantization parameter. It accepts an integer in range0-63. If not set, the filter will use the QP from the video stream (if available).strengthโ set filter strength. It accepts an integer in range-15to32. Lower values mean more details but also more artifacts, while higher values make the image smoother but also blurrier. Default value is0 โ PSNR optimal.use_bframe_qpโ enable the use of the QP from the B-Frames if set to1. Using this option may cause flicker since the B-Frames have often larger QP. Default is0(not enabled).
๐ fsync
Synchronize video frames with an external mapping from a file. Bestie this one is niche and I respect it.
For each input PTS given in the map file it either drops or creates as many frames as necessary to recreate the sequence of output frames given in the map file.
This filter is useful to recreate the output frames of a framerate conversion by the fps filter, recorded into a map file using the ffmpeg option -stats_mux_pre, and do further processing to the corresponding frames e.g. quality comparison.
Each line of the map file must contain three items per input frame, the input PTS (decimal), the output PTS (decimal) and the output TIMEBASE (decimal/decimal), separated by a space. This file format corresponds to the output of -stats_mux_pre_fmt="{ptsi} {pts} {tb}".
The filter assumes the map file is sorted by increasing input PTS.
The filter accepts the following options:
file,fโ the filename of the map file to be used.
Example:
# Convert a video to 25 fps and record a MAP_FILE file with the default format of this filter
ffmpeg -i INPUT -vf fps=fps=25 -stats_mux_pre MAP_FILE -stats_mux_pre_fmt "{ptsi} {pts} {tb}" OUTPUT
# Sort MAP_FILE by increasing input PTS
sort -n MAP_FILE
# Use INPUT, OUTPUT and the MAP_FILE from above to compare the corresponding frames in INPUT and OUTPUT via SSIM
ffmpeg -i INPUT -i OUTPUT -filter_complex '[0:v]fsync=file=MAP_FILE[ref];[1:v][ref]ssim' -f null -
๐ gblur
Apply Gaussian blur filter. Soft focus, but make it maths ๐ฆ.
The filter accepts the following options:
sigmaโ set horizontal sigma, standard deviation of Gaussian blur. Default is0.5.stepsโ Sets the number of steps used for the Gaussian approximation. Default is1.planesโ Picks which planes get filtered. By default every plane gets filtered. ๐ซsigmaVโ Sets the vertical sigma. If it's negative, it just uses the same value as"sigma". Default is-1.
Commands
This filter supports the same commands as options, bestie. The command takes the exact same syntax as the corresponding option.
If the expression you specify isn't valid, it just keeps its current value. No drama, no crash โ it stays where it was. ๐ซถ
geq
Applies a generic equation to every single pixel. Yes, literally every one. โจ
The filter accepts these options:
lum_expr,lumโ Sets the luma expression.cb_expr,cbโ Sets the chrominance blue expression.cr_expr,crโ Sets the chrominance red expression.alpha_expr,aโ Sets the alpha expression.red_expr,rโ Sets the red expression.green_expr,gโ Sets the green expression.blue_expr,bโ Sets the blue expression.
The colorspace is selected according to the options you specify. If one of lum_expr, cb_expr, or cr_expr is specified, the filter automatically selects a YCbCr colorspace. If one of red_expr, green_expr, or blue_expr is specified, it selects an RGB colorspace. ๐จ
If one of the chrominance expressions isn't defined, it falls back on the other one. If no alpha expression is specified, it evaluates to an opaque value. And if none of the chrominance expressions are specified, they all evaluate to the luma expression. Slay, honestly.
The expressions can use these variables and functions:
Nโ The sequential number of the filtered frame, starting from0.X,Yโ The coordinates of the current sample.W,Hโ The width and height of the image.SW,SHโ Width and height scale depending on the currently filtered plane. It's the ratio between the corresponding luma plane's number of pixels and the current plane's ones. E.g. for YUV4:2:0 the values are"1,1"for the luma plane, and"0.5,0.5"for chroma planes.Tโ Time of the current frame, expressed in seconds.p(x, y)โ Returns the value of the pixel at location(x,y)of the current plane.lum(x, y)โ Returns the value of the pixel at location(x,y)of the luma plane.cb(x, y)โ Returns the value of the pixel at location(x,y)of the blue-difference chroma plane. Returns0if there's no such plane.cr(x, y)โ Returns the value of the pixel at location(x,y)of the red-difference chroma plane. Returns0if there's no such plane.r(x, y),g(x, y),b(x, y)โ Return the value of the pixel at location(x,y)of the red/green/blue component. Returns0if there's no such component.alpha(x, y)โ Returns the value of the pixel at location(x,y)of the alpha plane. Returns0if there's no such plane.psum(x,y),lumsum(x, y),cbsum(x,y),crsum(x,y),rsum(x,y),gsum(x,y),bsum(x,y),alphasum(x,y)โ Sum of sample values in the rectangle from(0,0)to(x,y)โ this lets you grab sums of samples inside a rectangle. Peep the functions without thesumpostfix for the single-pixel versions. ๐งฎinterpolationโ Sets one of the interpolation methods:nearest,nbilinear,b
Default is bilinear.
For functions, if x and y are outside the area, the value gets automatically clipped to the closer edge. No out-of-bounds nonsense. ๐
โโ๏ธ
Heads up bestie ๐ โ this filter can use multiple threads, and in that case each slice has its own expression state. If you want only a single expression state (like, because your expressions depend on previous state), then you should limit the number of filter threads to 1.
Examples
- Flip the image horizontally:
geq=p(W-X\,Y)
- Generate a bidimensional sine wave, with angle
"PI/3"and a wavelength of 100 pixels:
geq=128 + 100*sin(2*(PI/100)*(cos(PI/3)*(X-50*T) + sin(PI/3)*Y)):128:128
- Generate a fancy enigmatic moving light:
nullsrc=s=256x256,geq=random(1)/hypot(X-cos(N*0.07)*W/2-W/2\,Y-sin(N*0.09)*H/2-H/2)^2*1000000*sin(N*0.02):128:128
- Generate a quick emboss effect:
format=gray,geq=lum_expr='(p(X,Y)+(256-p(X-4,Y-4)))/2'
- Modify RGB components depending on pixel position:
geq=r='X/W*r(X,Y)':g='(1-X/W)*g(X,Y)':b='(H-Y)/H*b(X,Y)'
- Create a radial gradient that's the same size as the input (also peep the
vignettefilter):
geq=lum=255*gauss((X/W-0.5)*3)*gauss((Y/H-0.5)*3)/gauss(0)/gauss(0),format=gray
gradfun
Fixes the banding artifacts that sometimes get introduced into nearly flat regions by truncation to 8-bit color depth. It interpolates the gradients that should be where the bands are, and dithers them. Iconic little glow-up for your gradients. ๐
It's designed for playback only. Do not use it prior to lossy compression, because compression tends to lose the dither and bring the bands right back. The audacity ๐ญ
It accepts these parameters:
strengthโ The maximum amount by which the filter will change any one pixel. This is also the threshold for detecting nearly flat regions. Acceptable values range from.51to64; the default value is1.2. Out-of-range values get clipped to the valid range.radiusโ The neighborhood to fit the gradient to. A larger radius makes for smoother gradients, but it also prevents the filter from modifying pixels near detailed regions. Acceptable values are8-32; the default value is16. Out-of-range values get clipped to the valid range.
Alternatively, the options can be specified as a flat string: strength[:radius]
Examples
- Apply the filter with a
3.5strength and radius of8:
gradfun=3.5:8
- Specify radius, omitting the strength (which falls back to the default value):
gradfun=radius=8
graphmonitor
Shows various filtergraph stats. With this filter you can debug a whole complete filtergraph โ especially issues with links filling up with queued frames. It's giving "X-ray vision for your graph" ๐๐
The filter accepts these options:
size,sโ Sets video output size. Default ishd720.opacity,oโ Sets video opacity. Default is0.9. Allowed range is from0to1.mode,mโ Sets output mode flags.
Available values for flags are:
fullโ No any filtering. Default.compactโ Show only filters with queued frames.nozeroโ Show only filters with non-zero stats.noeofโ Show only filters with non-eof stat.nodisabledโ Show only filters that are enabled in timeline.
flags,fโ Sets flags which enable which stats are shown in video.
Available values for flags are:
noneโ All flags turned off.allโ All flags turned on.queueโ Display number of queued frames in each link.frame_count_inโ Display number of frames taken from filter.frame_count_outโ Display number of frames given out from filter.frame_count_deltaโ Display delta number of frames between above two values.ptsโ Display current filtered frame pts.pts_deltaโ Display pts delta between current and previous frame.timeโ Display current filtered frame time.time_deltaโ Display time delta between current and previous frame.timebaseโ Display time base for filter link.formatโ Display used format for filter link.sizeโ Display video size or number of audio channels in case of audio used by filter link.rateโ Display video frame rate or sample rate in case of audio used by filter link.eofโ Display link output status.sample_count_inโ Display number of samples taken from filter.sample_count_outโ Display number of samples given out from filter.sample_count_deltaโ Display delta number of samples between above two values.disabledโ Show the timeline filter status.
rate,rโ Sets upper limit for video rate of output stream. Default value is25. This guarantees that output video frame rate will not be higher than this value. No cap on vibes tho โ
grayworld
A color constancy filter that applies color correction based on the grayworld assumption. ๐ฉถโจ
The algorithm uses linear light, so input data should be linearized beforehand (and possibly correctly tagged). Say it with me: linearize first, filter second ๐
ffmpeg -i INPUT -vf zscale=transfer=linear,grayworld,zscale=transfer=bt709,format=yuv420p OUTPUT
greyedge
A color constancy variation filter which estimates scene illumination via the grey edge algorithm and corrects the scene colors accordingly. Fancy academia behavior ๐๐
See: https://staff.science.uva.nl/th.gevers/pub/GeversTIP07.pdf
The filter accepts these options:
diffordโ The order of differentiation to be applied on the scene. Must be chosen in the range[0,2]and default value is1.minknormโ The Minkowski parameter to be used for calculating the Minkowski distance. Must be chosen in the range[0,20]and default value is1. Set to0for getting max value instead of calculating Minkowski distance.sigmaโ The standard deviation of Gaussian blur to be applied on the scene. Must be chosen in the range[0,1024.0]and default value =1.floor( sigma * break_off_sigma(3) )can't be equal to0ifdiffordis greater than0.
Examples
- Grey Edge:
greyedge=difford=1:minknorm=5:sigma=2
- Max Edge:
greyedge=difford=1:minknorm=0:sigma=2
guided
Applies a guided filter for edge-preserving smoothing, dehazing and so on. It's giving "soft but still sharp where it matters" ๐ฆ
The filter accepts these options:
radiusโ Sets the box radius in pixels. Allowed range is1to20. Default is3.epsโ Sets regularization parameter (with square). Allowed range is0to1. Default is0.01.modeโ Sets filter mode. Can be"basic"or"fast". Default is"basic".subโ Sets subsampling ratio for"fast"mode. Range is2to64. Default is4. No subsampling occurs in"basic"mode.guidanceโ Sets guidance mode. Can be"off"or"on". Default is"off". If"off", a single input is required. If"on", two inputs of the same resolution and pixel format are required. The second input serves as the guidance.planesโ Sets planes to filter. Default is first only.
Commands
This filter supports all the above options as commands. ๐ซถ
Examples
- Edge-preserving smoothing with guided filter:
ffmpeg -i in.png -vf guided out.png
- Dehazing, structure-transferring filtering, and detail enhancement via guided filter โ for how the guidance image gets generated, go read the paper "Guided Image Filtering", fr: <http://kaiminghe.com/publications/pami12guidedfilter.pdf>.
ffmpeg -i in.png -i guidance.png -filter_complex guided=guidance=on out.png
๐ haldclut
Slap a Hald CLUT onto a video stream. Iconic behavior.
Your first input is the video stream getting processed, and the second one is the Hald CLUT itself. And bestie, that CLUT input can be a single lil picture or a whole entire video stream โ dealer's choice ๐ .
This filter accepts the following options:
clutโ picks which CLUT video frames from the second input stream get processed. Can befirstorall. Default isall.shortestโ forces termination when the shortest input terminates. Default is0.repeatlastโ keeps applying the last CLUT after the stream ends. A value of0disables the filter once the last frame of the CLUT is reached. Default is1.
haldclut also has the same interpolation options as lut3d (the two filters share the same internals, they're literally twins ๐ซถ).
This filter also supports the framesync options.
More info about the Hald CLUT lives on Eskil Steenberg's website (he's the Hald CLUT author btw) at <http://www.quelsolaar.com/technology/clut.html>.
Commands
This filter supports the interp option as commands.
Workflow examples
Hald CLUT video stream โจ
Generate an identity Hald CLUT stream then mess with it using various effects:
ffmpeg -f lavfi -i haldclutsrc=8 -vf "hue=H=2*PI*t:s=sin(2*PI*t)+1, curves=cross_process" -t 10 -c:v ffv1 clut.nut
Note: make sure you use a lossless codec. No cap, this matters.
Then use it with haldclut to apply it on some random stream:
ffmpeg -f lavfi -i mandelbrot -i clut.nut -filter_complex '[0][1] haldclut' -t 20 mandelclut.mkv
So the Hald CLUT gets applied to the first 10 seconds (that's the duration of clut.nut), and after that the latest picture of that CLUT stream gets applied to the remaining frames of the mandelbrot stream. Slay.
Hald CLUT with preview ๐
A Hald CLUT is supposed to be a squared image of Level*Level*Level by Level*Level*Level pixels. For any given Hald CLUT, FFmpeg will select the biggest possible square starting at the top left of the picture. Whatever padding pixels are left over (bottom or right) get ignored. And guess what โ you can use that leftover area to add a preview of the Hald CLUT ๐
Typically, the following generated Hald CLUT will be supported by the haldclut filter:
ffmpeg -f lavfi -i haldclutsrc=8 -vf "
pad=iw+320 [padded_clut];
smptebars=s=320x256, split [a][b];
[padded_clut][a] overlay=W-320:h, curves=color_negative [main];
[main][b] overlay=W-320" -frames:v 1 clut.png
It contains the original and a preview of the effect of the CLUT: SMPTE color bars are displayed on the right-top, and below them the same color bars but run through the color changes. Chef's kiss.
Then the effect of this Hald CLUT can be visualized with:
ffplay input.mkv -vf "movie=clut.png, [in] haldclut"
๐ฆ hflip
Flips the input video horizontally. That's it, that's the whole filter, and honestly? Iconic simplicity.
For example, to horizontally flip the input video with ffmpeg:
ffmpeg -i in.avi -vf "hflip" out.avi
๐ธ histeq
This filter applies a global color histogram equalization, per-frame style.
It's the move for correcting video that has a compressed range of pixel intensities. The filter redistributes those pixel intensities so their distribution gets equalized across the intensity range. Think of it as your "automatically adjusting contrast filter". Lowkey it's only useful for correcting degraded or poorly captured source video โ that's its whole lane.
The filter accepts the following options:
strengthโ determines how much equalization gets applied. As the strength goes down, the distribution of pixel intensities more-and-more approaches that of the input frame. Value must be a float number in the range [0,1] and defaults to0.200.intensityโ sets the maximum intensity that can be generated and scales the output values appropriately. Set the strength how you want it, then limit the intensity if you need to avoid washing-out. Value must be a float number in the range [0,1] and defaults to0.210.antibandingโ sets the antibanding level. If enabled, the filter randomly varies the luminance of output pixels by a small amount so the histogram doesn't band. Possible values arenone,weakorstrong. Defaults tonone.
๐ histogram
Computes and draws a color distribution histogram for the input video. We love a data visualization moment ๐
The computed histogram is a representation of the color component distribution in an image.
Standard histogram displays the color components distribution in an image. It displays a color graph for each color component, showing the distribution of the Y, U, V, A or R, G, B components (depends on the input format, iykyk) in the current frame. Below each graph there's a color component scale meter.
The filter accepts the following options:
level_heightโ sets the height of the level. Default value is200. Allowed range is [50, 2048].scale_heightโ sets the height of the color scale. Default value is12. Allowed range is [0, 40].display_modeโ sets the display mode. It accepts the following values:stackโ per color component graphs are placed below each other.paradeโ per color component graphs are placed side by side.overlayโ presents information identical to what's inparade, except the graphs representing color components are superimposed directly over one another.
Default is stack.
levels_modeโ sets the mode. Can be eitherlinearorlogarithmic. Default islinear.componentsโ sets what color components to display. Default is7.fgopacityโ sets the foreground opacity. Default is0.7.bgopacityโ sets the background opacity. Default is0.5.colors_modeโ sets the colors mode. It accepts the following values:whiteonblackblackonwhitewhiteongrayblackongraycoloronblackcoloronwhitecolorongrayblackoncolorwhiteoncolorgrayoncolor
Default is whiteonblack.
Examples
- Calculate and draw a histogram:
ffplay -i input -vf histogram
๐ฅ hqdn3d
Okay so this one is a high precision/quality 3d denoise filter. Its whole goal is reducing image noise, producing smooth images and making still images really still. Also it should enhance compressibility. Main character denoising energy.
It accepts the following optional parameters:
luma_spatialโ a non-negative floating point number specifying spatial luma strength. Defaults to4.0.chroma_spatialโ a non-negative floating point number specifying spatial chroma strength. Defaults to3.0*luma_spatial/4.0.luma_tmpโ a floating point number specifying luma temporal strength. Defaults to6.0*luma_spatial/4.0.chroma_tmpโ a floating point number specifying chroma temporal strength. Defaults toluma_tmp*chroma_spatial/luma_spatial.
Commands
This filter supports the same commands as its options. The command accepts the same syntax as the corresponding option.
If the specified expression is not valid, it's kept at its current value. No dramatic exits, it just stays put ๐
โญ hwdownload
Downloads hardware frames to system memory.
The input must be in hardware frames, and the output has to be a non-hardware format. Heads up though: not all formats will be supported on the output โ you might need to insert an additional format filter immediately after it in the graph to get the output in a format that's actually supported. Consider yourself warned ๐
๐ hwmap
Maps hardware frames to system memory or to another device.
This filter has several different modes of operation, and which one gets used depends on the input and output formats:
- Hardware frame input, normal frame output โ maps the input frames to system memory and passes them to the output. If the original hardware frame is needed later (say, after overlaying something else on part of it), the
hwmapfilter can be used again in the next mode to retrieve it. - Normal frame input, hardware frame output โ if the input is actually a software-mapped hardware frame, then unmap it, i.e. return the original hardware frame.
Otherwise, a device must be provided. New hardware surfaces get created on that device for the output, then they're mapped back to the software format at the input and those frames get given to the preceding filter. This then acts like the hwupload filter, but it may be able to avoid an additional copy when the input is already in a compatible format. Efficiency queen ๐
- Hardware frame input and output โ a device must be supplied for the output, either directly or with the
derive_deviceoption. The input and output devices must be of different types and compatible โ the exact meaning of that is system-dependent, but typically it means they must refer to the same underlying hardware context (like, refer to the same graphics card).
If the input frames were originally created on the output device, then unmap to retrieve the original frames.
Otherwise, map the frames to the output device โ create new hardware frames on the output corresponding to the frames on the input.
The following additional parameters are accepted:
modeโ sets the frame mapping mode. Some combination of:readโ the mapped frame should be readable.writeโ the mapped frame should be writeable.overwriteโ the mapping will always overwrite the entire frame.
This may improve performance in some cases, since the original contents of the frame need not be loaded.
directโ the mapping must not involve any copying.
Indirect mappings to copies of frames get created in some cases where either direct mapping isn't possible or it would have unexpected properties. Setting this flag ensures the mapping is direct and will fail if that's not possible.
Defaults to read+write if not specified.
derive_devicetype โ instead of using the device supplied at initialisation, derive a new device of type type from the device the input frames exist on.reverseโ in a hardware to hardware mapping, map in reverse: create frames in the sink and map them back to the source. This may be necessary in some cases where a mapping in one direction is required but only the opposite direction is supported by the devices being used. Annoying but real ๐
โ ๏ธ Bestie, this next one is dangerous โ it may break the preceding filter in undefined ways if there are any additional constraints on that filter's output. Do not use it without fully understanding the implications of its use. Like, fr fr, do not.
๐ hwupload
Uploads system memory frames to hardware surfaces. Glow-up for your frames, basically.
The device you upload to must be supplied when the filter is initialised. If you're using ffmpeg, pick the right device with the -filter_hw_device option or with the derive_device option. The input and output devices have to be of different types and compatible โ the exact meaning of that is system-dependent, but typically it means they must refer to the same underlying hardware context (like, the same graphics card, iykyk).
The following additional parameters are accepted:
derive_devicetype โ instead of using the device supplied at initialisation, derive a brand new device of type type from the device the input frames exist on. So it's giving "make it make sense for this hardware" energy.
๐ง hwupload_cuda
Uploads system memory frames to a CUDA device. Same vibe, NVIDIA flavoured.
It accepts the following optional parameters:
deviceโ the number of the CUDA device to use.
๐ hqx
Applies a high-quality magnification filter designed for pixel art. This filter was originally created by Maxim Stepin โ icon behaviour, we stan.
It accepts the following option:
nโ set the scaling dimension:2forhq2x,3forhq3xand4forhq4x. Default is3.
๐ซถ hstack
Stacks input videos horizontally. Side-by-side slay.
All streams must be of same pixel format and of same height. No exceptions, bestie.
Note that this filter is faster than using overlay and pad filter to create same output. Speed, we love her.
The filter accepts the following option:
inputsโ set number of input streams. Default is2.shortestโ if set to1, force the output to terminate when the shortest input terminates. Default value is0.
๐ธ hsvhold
Turns a certain HSV range into gray values.
This filter measures color difference between the set HSV color in options and the ones measured in the video stream. Depending on options, output colors can be changed to be gray or not. Lowkey a desaturation dial, highkey useful.
The filter accepts the following options:
hueโ set the hue value which will be used in color difference calculation. Allowed range is from-360to360. Default value is0.satโ set the saturation value which will be used in color difference calculation. Allowed range is from-1to1. Default value is0.valโ set the value which will be used in color difference calculation. Allowed range is from-1to1. Default value is0.similarityโ set similarity percentage with the key color. Allowed range is from0to1. Default value is0.01.
0.00001 matches only the exact key color, while 1.0 matches everything. Pick your fighter ๐ฅ
blendโ blend percentage. Allowed range is from0to1. Default value is0.
0.0 makes pixels either fully gray, or not gray at all โ no in-between, very binary of her.
Higher values result in more gray pixels, with a higher gray pixel the more similar the pixel's color is to the key color.
๐ฆ hsvkey
Turns a certain HSV range into transparency.
This filter measures color difference between the set HSV color in options and the ones measured in the video stream. Depending on options, output colors can be changed to transparent by adding an alpha channel. Poof โ gone. ๐จ
The filter accepts the following options:
hueโ set the hue value which will be used in color difference calculation. Allowed range is from-360to360. Default value is0.satโ set the saturation value which will be used in color difference calculation. Allowed range is from-1to1. Default value is0.valโ set the value which will be used in color difference calculation. Allowed range is from-1to1. Default value is0.similarityโ set similarity percentage with the key color. Allowed range is from0to1. Default value is0.01.
0.00001 matches only the exact key color, while 1.0 matches everything.
blendโ blend percentage. Allowed range is from0to1. Default value is0.
0.0 makes pixels either fully transparent, or not transparent at all.
Higher values result in semi-transparent pixels, with a higher transparency the more similar the pixel's color is to the key color.
๐ hue
Modify the hue and/or the saturation of the input. The classic. The icon. The main character of color filters.
It accepts the following parameters:
hโ specify the hue angle as a number of degrees. It accepts an expression, and defaults to"0".sโ specify the saturation in the[-10,10]range. It accepts an expression and defaults to"1".Hโ specify the hue angle as a number of radians. It accepts an expression, and defaults to"0".bโ specify the brightness in the[-10,10]range. It accepts an expression and defaults to"0".
h and H are mutually exclusive, and can't be specified at the same time. One or the other, bestie, we don't do both. ๐ซ
The b, h, H and s option values are expressions containing the following constants:
nโ frame count of the input frame starting from0ptsโ presentation timestamp of the input frame expressed in time base unitsrโ frame rate of the input video,NANif the input frame rate is unknowntโ timestamp expressed in seconds,NANif the input timestamp is unknowntbโ time base of the input video
โจ Examples โจ
- Set the hue to
90degrees and the saturation to1.0:
hue=h=90:s=1
- Same command but expressing the hue in radians:
hue=H=PI/2:s=1
- Rotate hue and make the saturation swing between
0and2over a period of1second:
hue="H=2*PI*t: s=sin(2*PI*t)+1"
- Apply a
3seconds saturation fade-in effect starting at0:
hue="s=min(t/3\,1)"
The general fade-in expression can be written as:
hue="s=min(0\, max((t-START)/DURATION\, 1))"
- Apply a
3seconds saturation fade-out effect starting at5seconds:
hue="s=max(0\, min(1\, (8-t)/3))"
The general fade-out expression can be written as:
hue="s=max(0\, min(1\, (START+DURATION-t)/DURATION))"
๐ฎ Commands ๐ฎ
This filter supports the following commands:
b,s,h,Hโ modify the hue and/or the saturation and/or brightness of the input video. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value. No crash, no drama, it just stays put.
๐ huesaturation
Apply hue-saturation-intensity adjustments to input video stream. The whole trio, handled.
This filter operates in RGB colorspace โ heads up, that's where it lives.
This filter accepts the following options:
hueโ set the hue shift in degrees to apply. Default is0. Allowed range is from-180to180.saturationโ set the saturation shift. Default is0. Allowed range is from-1to1.intensityโ set the intensity shift. Default is0. Allowed range is from-1to1.colorsโ set which primary and complementary colors are going to be adjusted. This option is set by providing one or multiple values. This can select multiple colors at once. By default all colors are selected.rโ adjust reds.yโ adjust yellows.gโ adjust greens.cโ adjust cyans.bโ adjust blues.mโ adjust magentas.aโ adjust all colors.
strengthโ set strength of filtering. Allowed range is from0to100. Default value is1.rw,gw,bwโ set weight for each RGB component. Allowed range is from0to1. By default is set to0.333,0.334,0.333. Those options are used in saturation and lightess processing. (Yes, that typo is canon, we keep it.)lightnessโ set preserving lightness, by default is disabled. Adjusting hues can change lightness from original RGB triplet; with this option enabled lightness is kept at same value. So your colors shift but your brightness stays seated. ๐
โญ hysteresis
Grow first stream into second stream by connecting components. This makes it possible to build more robust edge masks โ it's giving "connect the dots but make it computer vision".
This filter accepts the following options:
planesโ set which planes will be processed as bitmap, unprocessed planes will be copied from first stream. By default value0xf, all planes will be processed.thresholdโ set threshold which is used in filtering. If pixel component value is higher than this value filter algorithm for connecting components is activated. By default value is0.
The hysteresis filter also supports the framesync options.
๐ฅ iccdetect
Detect the colorspace from an embedded ICC profile (if present), and update the frame's tags accordingly. Detective energy. ๐ต๏ธโโ๏ธ
This filter accepts the following options:
forceโ if true, the frame's existing colorspace tags will always be overridden by values detected from an ICC profile. Otherwise, they will only be assigned if they containunknown. Enabled by default.
๐ iccgen
Generate ICC profiles and attach them to frames. Making profiles out of thin air, iconic.
This filter accepts the following options:
color_primaries,color_trcโ configure the colorspace that the ICC profile will be generated for. The default value ofautoinfers the value from the input frame's metadata, defaulting to BT.709/sRGB as appropriate.
See the setparams filter for a list of possible values, but note that unknown are not valid values for this filter. Don't even try it.
forceโ if true, an ICC profile will be generated even if it would overwrite an already existing ICC profile. Disabled by default. So it'll respect your existing profile unless you tell it not to ๐ซถ
๐ง identity
Obtain the identity score between two input videos. It's a comparison filter, and honestly kind of a vibe.
This filter takes two input videos.
Both input videos must have the same resolution and pixel format for this filter to work correctly. Also it assumes that both inputs have the same number of frames, which are compared one by one. Keep 'em matched, bestie.
The obtained per component, average, min and max identity score is printed through the logging system.
The filter stores the calculated identity scores of each frame in frame metadata.
This filter also supports the framesync options.
In the below example the input file main.mpg being processed is compared with the reference file ref.mpg.
ffmpeg -i main.mpg -i ref.mpg -lavfi identity -f null -
๐ idet
Detect video interlacing type. The "what even are you" filter.
This filter tries to detect if the input frames are interlaced, progressive, top or bottom field first. It will also try to detect fields that are repeated between adjacent frames (a sign of telecine).
Single frame detection considers only immediately adjacent frames when classifying each frame. Multiple frame detection incorporates the classification history of previous frames. Like, one's looking at the neighbours, the other's got lore. ๐ญ
The filter will log these metadata values:
single.current_frameโ detected type of current frame using single-frame detection. One of:tff'' (top field first),bff'' (bottom field first),progressive'', orundetermined''
single.tffโ running total of frames that got flagged top field first by the single-frame detector ๐multiple.tffโ same thing but the multiple-frame detector did the flagging, cumulative count โจsingle.bffโ cumulative count of frames detected as bottom field first, single-frame detection ๐multiple.current_frameโ the detected type of the current frame, via multiple-frame detection. It's one of:tff(top field first),bff(bottom field first),progressive, orundetermined๐ฆmultiple.bffโ cumulative number of frames detected as bottom field first using multiple-frame detection ๐ธsingle.progressiveโ cumulative number of frames detected as progressive, single-frame detection ๐multiple.progressiveโ cumulative number of frames detected as progressive, multiple-frame detection ๐ซถsingle.undeterminedโ how many frames the single-frame detector just couldn't classify, cumulative ๐ญmultiple.undeterminedโ same deal, but the multiple-frame detector's "idk bestie" pile ๐ฅrepeated.current_frameโ which field in the current frame is repeated from the last one. One ofneither,top, orbottom๐repeated.neitherโ cumulative count of frames with no repeated field ๐repeated.topโ cumulative count of frames whose top field is repeated from the previous frame's top field โญrepeated.bottomโ cumulative count of frames whose bottom field is repeated from the previous frame's bottom field ๐
This filter takes the following options:
intl_thresโ sets the interlacing threshold ๐prog_thresโ sets the progressive threshold ๐rep_thresโ the threshold for repeated field detection ๐งhalf_lifeโ number of frames after which a given frame's contribution to the stats gets halved (so it only contributes0.5to its classification). The default of0means every frame ever seen keeps its full weight of1.0forever, no cap ๐analyze_interlaced_flagโ when this isn't0,idetuses the specified number of frames to figure out whether the interlaced flag is actually accurate, and it won't count undetermined frames while doing it. If the flag turns out accurate, it's used with no further computation; if it turns out inaccurate, it gets cleared with no further computation. The whole point is you can drop theidetfilter in as a low-compute way to clean up the interlaced flag โจ
Examples
Wanna inspect the field order of the first 360 frames of a video, in full verbose detail? Say less:
ffmpeg -i INPUT -filter:v idet,metadata=mode=print -frames:v 360 -an -f null -
The idet filter slaps analysis metadata onto every frame, and then that metadata gets discarded. At the end the filter also prints a final report with all the statistics ๐
il
Deinterleave or interleave fields, bestie ๐ฆ
This filter lets you process the fields of interlaced images without deinterlacing them. Deinterleaving splits the input frame into 2 fields (aka half pictures) โ odd lines get moved to the top half of the output image, even lines to the bottom half. Then you can process (filter) those bad boys independently and re-interleave them after ๐
It accepts the following options:
luma_mode,l/chroma_mode,c/alpha_mode,aโ available values forluma_mode,chroma_modeandalpha_modeare:noneโ do nothing ๐deinterleave,dโ deinterleave fields, placing one above the otherinterleave,iโ interleave fields, reversing the effect of deinterleaving- Default value is
none๐
luma_swap,ls/chroma_swap,cs/alpha_swap,asโ swap the luma/chroma/alpha fields, exchanging even & odd lines. Default value is0๐ธ
Commands
This filter supports all the above options as commands โจ
inflate
Apply the inflate effect to the video ๐ซง
This filter replaces the pixel with the local (3x3) average, only counting values higher than the pixel itself.
It accepts the following options:
threshold0/threshold1/threshold2/threshold3โ limit the maximum change for each plane; default is65535. If it's0, that plane stays completely unchanged ๐
Commands
This filter supports all the above options as commands ๐ซ
interlace, interlace_vulkan
Simple interlacing filter for progressive content ๐ฅ It interleaves the upper (or lower) lines from odd frames with the lower (or upper) lines from even frames โ halving the frame rate and preserving image height, iconic behaviour honestly ๐
Original Original New Frame
Frame 'j' Frame 'j+1' (tff)
========== =========== ==================
Line 0 --------------------> Frame 'j' Line 0
Line 1 Line 1 ----> Frame 'j+1' Line 1
Line 2 ---------------------> Frame 'j' Line 2
Line 3 Line 3 ----> Frame 'j+1' Line 3
... ... ...
New Frame + 1 will be generated by Frame 'j+2' and Frame 'j+3' and so on
It accepts the following optional parameters:
scanโ decides whether the interlaced frame is taken from the even lines (tffโ the default) or the odd lines (bff) of the progressive frame ๐lowpassโ vertical lowpass filter to avoid twitter interlacing and reduce moire patterns, and it comes in flavours:0,offโ disable the vertical lowpass filter1,linearโ enable the linear filter (this one's the default) โญ2,complexโ enable the complex filter. This reduces twitter and moire slightly less, but retains detail and that subjective sharpness impression better ๐
kerndeint
Deinterlace the input video by applying Donald Graft's adaptive kernel deinterling ๐ง โจ It works on the interlaced parts of a video to produce progressive frames.
Here's the rundown of the accepted parameters:
threshโ sets the threshold that affects the filter's tolerance when deciding whether a pixel line must be processed. It has to be an integer in the range[0,255]and defaults to10. A value of0means the process gets applied to every single pixel ๐ณmapโ paint pixels exceeding the threshold value white if set to1. Default is0๐จorderโ sets the fields order. Swap fields if set to1, leave fields alone if0. Default is0๐sharpโ enable additional sharpening if set to1. Default is0๐ชtwowayโ enable twoway sharpening if set to1. Default is0โ๏ธ
Examples
- Apply default values:
kerndeint=thresh=10:map=0:order=0:sharp=0:twoway=0
- Enable additional sharpening:
kerndeint=sharp=1
- Paint processed pixels in white:
kerndeint=map=1
kirsch
Apply the kirsch operator to the input video stream ๐
The filter accepts the following option:
planesโ set which planes get processed; unprocessed planes just get copied. By default the value is0xf, meaning all planes get processed ๐scaleโ set the value that gets multiplied with the filtered result โจdeltaโ set the value that gets added to the filtered result ๐
Commands
This filter supports all the above options as commands ๐ซ
lagfun
Slowly update darker pixels ๐
This filter makes short flashes of light appear longer โ obsessed with the vibes honestly. It accepts the following options:
decayโ set the factor for decaying. Default is.95. Allowed range is from0to1๐planesโ set which planes to filter. Default is all. Allowed range is from0to15๐ฆ
Commands
This filter supports all the above options as commands โจ
lenscorrection
Correct radial lens distortion ๐ท๐
This filter fixes radial distortion like the kind you get from wide angle lenses, and re-rectifies the image while it's at it. To find the right parameters you can use tools โ opencv for example โ or just go full trial-and-error, no judgement ๐ซถ To use opencv, grab the calibration sample (under samples/cpp) from the opencv sources and pull the k1 and k2 coefficients out of the resulting matrix.
Fun fact: effectively the same filter exists in the open-source tools Krita and Digikam from the KDE project ๐
And heads up โ contrast this with the vignette filter, which can also compensate for lens errors, but this filter corrects the distortion of the image while vignette corrects the brightness distribution. So you might wanna use both together in certain cases, though you'll have to handle the ordering yourself, i.e. whether vignetting should be applied before or after lens correction โ ๏ธ
Options
The filter accepts the following options:
cxโ relative x-coordinate of the focal point of the image, and therefore the center of the distortion. Range is[0,1], expressed as fractions of the image width. Default is0.5๐cyโ relative y-coordinate of the focal point of the image, and therefore the center of the distortion. Range is[0,1], expressed as fractions of the image height. Default is0.5๐ธk1โ coefficient of the quadratic correction term. Range is[-1,1].0means no correction. Default is0โจk2โ coefficient of the double quadratic correction term. Range is[-1,1].0means no correction. Default is0๐iโ set the interpolation type. Can benearestorbilinear. Default isnearest๐fcโ specify the color of the unmapped pixels. For the syntax of this option, check the "Color" section in theffmpeg-utilsmanual. Default color isblack@0๐ค
The formula that generates the correction is:
r_src = r_tgt * (1 + k1 * (r_tgt / r_0)^2 + k2 * (r_tgt / r_0)^4)
where r_0 is halve of the image diagonal and r_src and r_tgt are the distances from the focal point in the source and target images, respectively ๐งฎ
Commands
This filter supports all the above options as commands ๐ซ
lensfun
Apply lens correction via the lensfun library (<http://lensfun.sourceforge.net/>) ๐
The lensfun filter needs the camera make, camera model, and lens model to apply lens correction. It loads the lensfun database and queries it to find the matching camera and lens entries in there. As long as those entries can be found with the options you gave, the filter can perform corrections on frames ๐
Heads up though: incomplete strings mean the filter picks the best match it can from your options, and it'll output the chosen camera and lens models (logged at level info). You must provide the make, camera model, and lens model โ they're required, no skipping ๐ซถ
So like, to get a list of every make and model that exists? Just leave out one or both of the make and model options and the filter will dump the whole list into the log at level INFO. First column = the make, second column = the model. And for lenses? Set any values for make and model but leave out the lens_model option, and it'll send the full lens list to the log at level INFO too. Heads up: the ffmpeg tool will exit right after the list gets printed, so don't expect it to keep going ๐
The filter accepts these options, bestie:
makeโ the make of the camera (like"Canon"). This one's required, no skipping ๐ซถmodelโ the model of the camera (like"Canon EOS 100D"). Also required.lens_modelโ the model of the lens (like"Canon EF-S 18-55mm f/3.5-5.6 IS STM"). Required too, yeah all three ๐db_pathโ the full path to the lens database folder. If you don't set it, the filter tries to load the database from the install path it was built with. Default is unset.modeโ what kind of correction we're doing. Valid values are:vignettingโ fixes lens vignetting.geometryโ fixes lens geometry. This is the default.subpixelโ fixes chromatic aberrations.vig_geoโ fixes vignetting and geometry, two for one โจvig_subpixelโ fixes vignetting and chromatic aberrations.distortionโ fixes both lens geometry and chromatic aberrations.allโ enables every possible correction. go big or go home ๐ฅ
focal_lengthโ the focal length of the image/video (that's zoom, and it's expected to be constant for video). Like, an 18โ55mm lens has a focal length range of [18โ55], so pick a value in that range when you're using that lens. Default18.apertureโ the aperture of the image/video (expected constant for video). Note that aperture is only used for vignetting correction. Default3.5.focus_distanceโ the focus distance of the image/video (expected constant for video). Note that focus distance is only used for vignetting and only slightly affects the vignetting correction process. If you don't know it, just leave it at the default value (which is1000).scaleโ the scale factor applied after transformation. After correction the video isn't necessarily rectangular anymore, and this parameter controls how much of the resulting image is visible. A value of0means a value gets chosen automatically so there's little or no unmapped area in the output image.1.0means no additional scaling happens at all. Lower values may result in more of the corrected image being visible, while higher values may avoid unmapped areas in the output.target_geometryโ the target geometry of the output image/video. Valid options are:rectilinear(default)fisheyepanoramicequirectangularfisheye_orthographicfisheye_stereographicfisheye_equisolidfisheye_thoby
reverseโ apply the reverse of image correction (so instead of correcting distortion, you apply it ๐).interpolationโ the type of interpolation used when correcting distortion. Valid values are:nearestlinear(default)lanczos
๐ธ Examples ๐ธ
- Apply lens correction with make
"Canon", camera model"Canon EOS 100D", and lens model"Canon EF-S 18-55mm f/3.5-5.6 IS STM"with focal length of"18"and aperture of"8.0".
ffmpeg -i input.mov -vf lensfun=make=Canon:model="Canon EOS 100D":lens_model="Canon EF-S 18-55mm f/3.5-5.6 IS STM":focal_length=18:aperture=8 -c:v h264 -b:v 8000k output.mov
- Same thing as before, but only for the first 5 seconds of video โณ
ffmpeg -i input.mov -vf lensfun=make=Canon:model="Canon EOS 100D":lens_model="Canon EF-S 18-55mm f/3.5-5.6 IS STM":focal_length=18:aperture=8:enable='lte(t\,5)' -c:v h264 -b:v 8000k output.mov
๐ฆ lcevc ๐ฆ
Low Complexity Enhancement Video Codec filter, based on liblcevc_dec (<https://github.com-v-novaltd/LCEVCdec>). Okay so literally the link in the manpage is <https://github.com-v-novaltd/LCEVCdec> โ copy it exactly, don't @ me ๐ญ
๐ libplacebo ๐
Flexible GPU-accelerated processing filter based on libplacebo (<https://code.videolan.org/videolan/libplacebo>). GPU go brrr โจ
Options
The options for this filter are split into the following sections:
๐ Output mode ๐
These options control the overall output mode. By default, libplacebo tries to preserve the source colorimetry and size as best as it can โ but it will apply any embedded film grain, dolby vision metadata or anamorphic SAR present in source frames.
inputsโ set the number of inputs. This can be used, alongside theidxvariable, to allow placing/blending multiple inputs inside the output frame. Basically it enables functionality similar tohstack,overlay, etc. multi-input main character energy ๐ซถw,hโ set the output video dimension expression. Defaults areiwandih. Allows the same expressions as thescalefilter.crop_x,crop_yโ set the input crop x/y expressions, defaults are(iw-cw)/2and(ih-ch)/2.crop_w,crop_hโ set the input crop width/height expressions, defaults areiwandih.pos_x,pos_yโ set the output placement x/y expressions, defaults are(ow-pw)/2and(oh-ph)/2.pos_w,pos_hโ set the output placement width/height expressions, defaults areowandoh.rotateโ rotate the input frame clockwise by the specified angle. The values are0,360,90,180,270.fpsโ set the output frame rate. This can be rational, e.g.60000/1001. If set to the special stringnone(the default), input timestamps get passed through to the output unmodified instead. Otherwise the input video frames will be interpolated as necessary to rescale the video to the specified target framerate, in a manner as determined by theframe_mixeroption.formatโ set the output format override. If unset (the default), frames get output in the same format as the respective input frames. Otherwise format conversion is performed.force_original_aspect_ratio,force_divisible_byโ work the same as the identicalscalefilter options. Note thatforce_divisible_byalso works withfit_sense=constraint.reset_sarโ if enabled, output frames will always have a pixel aspect ratio of 1:1. If disabled (the default), any aspect ratio mismatches โ including those from e.g. anamorphic video sources โ are forwarded to the output pixel aspect ratio.normalize_sarโ likereset_sar, but instead of stretching the video content to fill the new output aspect ratio, the content gets padded or cropped as necessary instead. Mutually exclusive withfit_mode. Disabled by default.pad_crop_ratioโ specifies a ratio (between0.0and1.0) between padding and cropping when the input aspect ratio doesn't match the output aspect ratio andnormalize_saris in effect. The default of0.0always pads the content with black borders, while a value of1.0always crops off parts of the content. Intermediate values are possible, leading to a mix of the two approaches โจfit_modeโ specify the content fit strategy according to a list of predefined modes. Determines how the input image is to be placed inside the destination crop rectangle (as defined bypos_x/yandpos_w/h). The names and their implementations are taken from the CSS'object-fit'property. Note that this option is mutually exclusive withnormalize_sar. Defaults tofill. Valid values are:fillโ stretch the input to the output rectangle, ignoring aspect ratio mismatches. Note that unlessreset_saris also enabled, the output will still have the correct pixel aspect ratio tagged.containโ scale the input to fit inside the output, preserving aspect ratio by padding. Equivalent tonormalize_sarwithpad_crop_ratioset to0.0.coverโ scale the input to fill the output, preserving aspect ratio by cropping. Equivalent tonormalize_sarwithpad_crop_ratioset to1.0.none,placeโ don't scale the input. The input gets placed inside the output rectangle at its natural size, which may result in additional padding or cropping.scale_downโ scale the input down as much as needed to fit inside the output. Equivalent to eithercontainornone, depending on whether the input is larger than the output or not.
fit_senseโ whenfit_modeis in use, this option controls how the fit strategy is applied against the specified output resolution. Mutually exclusive withforce_original_aspect_ratio. Valid values are:targetโ the computed output resolution is taken as the exact size of the output frame. This is the default behavior.constraintโ the computed output resolution is a size reference against which the fit mode is applied, enlarging or decreasing the true frame size as needed to fit the content.
fillcolorโ set the color used to fill the output area not covered by the output image, for example as a result ofnormalize_sar. For the general syntax of this option, check the "Color" section in theffmpeg-utilsmanual. Defaults toblack@0.corner_roundingโ render frames with rounded corners ๐ The value, given as a float ranging from0.0to1.0, indicates the relative degree of rounding, from fully square to fully circular. In other words, it gives the radius divided by half the smaller side length. Defaults to0.0.lutโ specifies a custom LUT (in Adobe.cubeformat) to apply to the colors as part of color conversion. The exact interpretation depends on the value oflut_type.lut_typeโ controls the interpretation of color values fed to and from the LUT specified aslut. Valid values are:autoโ chooses the interpretation of the LUT automatically from tagged metadata, and otherwise falls back tonative. (Default)nativeโ applied to raw image contents in its native RGB colorspace (non-linear light), before conversion to the output color space.normalizedโ applied to the normalized RGB image contents, in linear light, before conversion to the output color space.
conversionโ this one straight-up replaces the whole conversion from image color space โ output color space. If a LUT like this is present it's the top dog ๐: highest priority, overrides any ICC profiles, and also overrides the tone mapping / output colorimetry options (color_primaries,color_trc). Like, it does not share the aux cord, bestie.extra_optsโ passes extra libplacebo internal config options through. Format is a list ofkey=valuepairs separated by:. The example below shows how to set a custom filter kernel ("EWA LanczosSharp") and use it to double the input image resolution:
-vf "libplacebo=w=iw*2:h=ih*2:extra_opts='upscaler=custom\:upscaler_preset=ewa_lanczos\:upscaler_blur=0.9812505644269356'"
shader_cacheโ file path of a cache directory where libplacebo stashes and loads cached shader objects โจ. Heads up though: this cache is not cleaned up automatically (it's giving "I'll do it later" energy, and later never comes). If the path doesn't end in a directory separator, the generated filenames get effectively prefixed by the last path component. And all directories must already exist โ libplacebo is not your mom, it will not mkdir for you.
-vf "libplacebo=shader_cache=/tmp/pl-shader-"
colorspace,color_primaries,color_trc,range,chroma_locationโ configures the colorspace that output frames will be delivered in ๐จ. The default value"auto"outputs frames in the same format as the input frames, which means... literally no change, iconic. For any other value, an actual conversion gets performed.
See the setparams filter for the full list of possible values.
alpha_modeโ picks the output alpha mode you want, but only when the output format actually has an alpha channel. Same deal: see thesetparamsfilter for the possible values.apply_filmgrainโ applies film grain (think AV1 or H.274) if it's present in the source frames, and strips it from the output. Enabled by default ๐๏ธ.apply_dolbyvisionโ applies Dolby Vision RPU metadata if present in the source frames, and strips it from the output. Also enabled by default. Important caveat: Dolby Vision will always output BT.2020+PQ, overriding the usual input frame metadata. Those values also get picked as the values of"auto"for the respective frame output options. So DV is the main character and it knows it ๐.
okay so in addition to the expression constants documented for the scale filter, the crop_w, crop_h, crop_x, crop_y, pos_w, pos_h, pos_x and pos_y options can also contain these constants ๐
in_idx,idxโ the (0-based) numeric index of the currently active input stream.crop_w,cwandcrop_h,chโ the computed values ofcrop_wandcrop_h.pos_w,pwandpos_h,phโ the computed values ofpos_wandpos_h.in_t,tโ the input frame timestamp, in seconds.NANif the input timestamp is unknown ๐ญ.out_t,otโ the input frame timestamp, in seconds.NANif input timestamp is unknown. (yes, it says input in both โ that's what the page says, don't come for me ๐)nโ the input frame number, starting with 0.
โจ Scaling โจ
The options in this section control how libplacebo does upscaling and (if necessary) downscaling. Lowkey important note: libplacebo will always internally operate on 4:4:4 content, so any sub-sampled chroma formats like "yuv420p" will necessarily get upsampled and downsampled as part of the rendering process ๐ตโ๐ซ. Which means scaling might be in effect even if the source and destination resolution are the same. Wild, I know. ๐
upscaler,downscalerโ configure the filter kernel used for upscaling and downscaling respectively. The defaults are"spline36"and"mitchell". For a full list of possible values, pass"help"to these options. The most important values are:noneโ forces the use of built-in GPU texture sampling (typically bilinear). Extremely fast but poor quality, especially when downscaling ๐.bilinearโ bilinear interpolation. Can generally be done for free on GPUs, except when doing so would lead to aliasing. Fast and low quality.nearestโ nearest-neighbour interpolation. Sharp but highly aliasing.oversampleโ algorithm that looks visually similar to nearest-neighbour interpolation but tries to preserve pixel aspect ratio. Good for pixel art ๐ฎ, since it results in minimal distortion of the artistic appearance.lanczosโ standard sinc-sinc interpolation kernel.spline36โ cubic spline approximation of lanczos. No difference in performance, but has very slightly less ringing.ewa_lanczosโ elliptically weighted average version of lanczos, based on a jinc-jinc kernel. Also popularly referred to as just "Jinc scaling" โจ. Slow but very high quality.gaussianโ gaussian kernel. Has certain ideal mathematical properties, but subjectively very blurry ๐ซ .mitchellโ cubic BC spline with parameters recommended by Mitchell and Netravali. Very little ringing.
frame_mixerโ controls the kernel used for mixing frames temporally. Default is"none", which disables frame mixing entirely. For the full list of possible values, pass"help"to this option. The most important ones:noneโ disables frame mixing, giving a result equivalent to"nearest neighbour"semantics.oversampleโ oversamples the input video to create a "Smooth Motion"-type effect: if an output frame would exactly fall on the transition between two video frames, it gets blended according to the relative overlap. This is the recommended option whenever preserving the original subjective appearance is the goal ๐ฏ.mitchell_clampโ larger filter kernel that smoothly interpolates multiple frames in a manner designed to eliminate ringing and other artefacts as much as possible. Recommended wherever maximum visual smoothness is desired.linearโ linear blend/fade between frames. Especially useful for constructing e.g. slideshows ๐ผ๏ธ.
antiringingโ enables anti-ringing (for non-EWA filters). The value (between0.0and1.0) configures the strength of the anti-ringing algorithm. May increase aliasing if set too high โ ๏ธ. Disabled by default.sigmoidโ enables sigmoidal compression during upscaling. Reduces ringing slightly. Enabled by default.
๐ธ Deinterlacing ๐ธ
Deinterlacing is automatically supported when frames are tagged as interlaced โ BUT (and this is the plot twist) frames are not deinterlaced unless a deinterlacing algorithm is actually chosen. So like, tag all you want, nothing happens on its own ๐ .
deinterlaceโ the deinterlacing algorithm to use.weaveโ no deinterlacing, just weaves the fields together into a single frame. This is the default.bobโ naive bob deinterlacing, simply repeats each field line twice.yadifโ yet another deinterlacing filter. See theyadiffilter for more details.bwdifโ bob weaver deinterlacing filter. See thebwdiffilter for more details.
skip_spatial_checkโ skips the spatial deinterlacing check when using"yadif"deinterlacing.send_fieldsโ outputs a frame for each field, rather than for each frame. Note that this will always double the tagged output frame rate, even if the input doesn't contain any interlaced frames ๐ณ. Disabled by default.
๐ Debanding ๐
Libplacebo comes with a built-in debanding filter that's genuinely good at counteracting many common sources of banding and blocking. Turning this on is highly recommended whenever quality is desired โ it's giving "just trust me" and for once it's right ๐ซถ.
debandโ enables the (fast) debanding algorithm. Disabled by default.deband_iterationsโ number of deband iterations of the debanding algorithm. Each iteration is performed with progressively increased radius (and diminished threshold). Recommended values are in the range1to4. Defaults to1.deband_thresholdโ debanding filter strength. Higher numbers = more aggressive debanding. Defaults to4.0.deband_radiusโ debanding filter radius. A higher radius is better for slow gradients, while a lower radius is better for steep gradients. Defaults to16.0.deband_grainโ amount of extra output grain to add. Helps hide imperfections ๐. Defaults to6.0.
๐ Color adjustment ๐
A whole collection of subjective color controls. Ngl it's not very rigorous, so the exact effect will vary somewhat depending on the input primaries and colorspace โ it's vibes-based color science, and that's fine ๐.
brightnessโ brightness boost, between-1.0and1.0. Defaults to0.0.contrastโ contrast gain, between0.0and16.0. Defaults to1.0.saturationโ saturation gain, between0.0and16.0. Defaults to1.0.hueโ hue shift in radians, between-3.14and3.14. Defaults to0.0. This rotates the UV subvector, defaulting to BT.709 coefficients for RGB inputs ๐ก.gammaโ gamma adjustment, between0.0and16.0. Defaults to1.0.temperatureโ color temperature adjustment. Lower values make the output warmer/redder, down to1667, while higher values make the output cooler/bluer, up to25000. Defaults to6500(neutral white) ๐ก๏ธ.conesโ cone model to use for color blindness simulation. Accepts any combination of"l","m"and"s". Some examples:mโ Deuteranomaly / deuteranopia (affecting 3%-4% of the population)lโ Protanomaly / protanopia (affecting 1%-2% of the population)l+mโ Monochromacy (very rare)l+m+sโ Achromatopsy (complete loss of daytime vision, extremely rare)
cone-strengthโ gain factor for the cones specified bycones, between0.0and10.0. A value of1.0results in no change to color vision. A value of0.0(the default) simulates complete loss of those cones. Values above1.0result in exaggerating the differences between cones, which may help compensate for reduced color vision ๐ฆ.
โญ Peak detection โญ
So to help deal with sources that only have static HDR10 metadata (or no tagging whatsoever ๐ญ), libplacebo uses its own internal frame analysis compute shader to analyze source frames and adapt the tone mapping function in realtime. If that's too slow, or if you need exactly reproducible frame-perfect results, it's recommended to turn this feature off. Your call, bestie.
peak_detectโ enables HDR peak detection. Ignores static MaxCLL/MaxFALL values in favor of dynamic detection from the input ๐ฅ. Note that the detected values do not get written back to the output frames โ they merely guide the internal tone mapping process. Enabled by default.smoothing_periodโ peak detection smoothing period, between0.0and1000.0. Higher values make peak detection less responsive to changes in the input. Defaults to20.0.scene_threshold_low,scene_threshold_highโ the lower and upper thresholds for scene change detection, bestie. Theyโre expressed on a logarithmic scale between0.0and100.0. Defaults are1.0and3.0respectively. Setting either one to a negative value disables this functionality.percentileโ which percentile of the frame brightness histogram gets used as the source peak for tone-mapping. Defaults to99.995, which is a fairly conservative value. Setting it to100.0disables frame histogram measurement and instead uses the true peak brightness for tone-mapping. ๐
๐จ Tone mapping ๐จ
The options in this section control how libplacebo does tone-mapping and gamut-mapping when the content is wide-gamut or HDR and the output is likeโฆ not. In general, libplacebo relies on accurate source tagging and mastering display gamut information to produce the best results. So like, tag ur stuff correctly, okay? ๐ซถ
gamut_modeโ how to handle out-of-gamut colors that can happen as a result of colorimetric gamut mapping. The values are giving:clipโ do nothing, just clip out-of-range colors to the RGB volume. Low quality but extremely fast. โกperceptualโ perceptually soft-clip colors to the gamut volume. This is the default.relativeโ relative colorimetric hard-clip. Similar toperceptualbut without the soft knee.saturationโ saturation mapping, maps primaries directly to primaries in RGB space. Not recommended except for artificial computer graphics where a bright, saturated display is the desired vibe.absoluteโ absolute colorimetric hard-clip. Performs no adjustment of the white point.desaturateโ hard-desaturates out-of-gamut colors towards white while preserving the luminance. Has a tendency to distort the visual appearance of bright objects. ๐ญdarkenโ linearly reduces content brightness to preserve saturated details, followed by clipping the remaining out-of-gamut colors.warnโ highlight out-of-gamut pixels by inverting/marking them.linearโ linearly reduces chromaticity of the entire image to make it fit within the target color volume. Be careful when using this on BT.2020 sources without proper mastering metadata, because doing so will lead to excessive desaturation. โ ๏ธ
tonemappingโ tone-mapping algorithm to use. Available values are:autoโ automatic selection based on internal heuristics. This is the default. โจclipโ performs no tone-mapping, just clips out-of-range colors. Retains perfect color accuracy for in-range colors but completely destroys out-of-range information. Does not perform any black point adaptation. Not configurable.st2094-40โ EETF from SMPTE ST 2094-40 Annex B, which applies the Bezier curves from HDR10+ dynamic metadata based on Bezier curves to perform tone-mapping. The OOTF used is adjusted based on the ratio between the targeted and actual display peak luminances.st2094-10โ EETF from SMPTE ST 2094-10 Annex B.2, which takes into account the input signal average luminance in addition to the maximum/minimum. The configurable contrast parameter influences the slope of the linear output segment, defaulting to1.0for no increase/decrease in contrast. Note that this does not currently include the subjective gain/offset/gamma controls defined in Annex B.3.bt.2390โ EETF from the ITU-R Report BT.2390, a hermite spline roll-off with a linear segment. The knee point offset is configurable. Note that this parameter defaults to1.0, rather than the value of0.5from the ITU-R spec. ๐bt.2446aโ EETF from ITU-R Report BT.2446, method A. Designed for well-mastered HDR sources. Can be used for both forward and inverse tone mapping. Not configurable.splineโ simple spline consisting of two polynomials, joined by a single pivot point. The parameter gives the pivot point in PQ space, defaulting to0.30. Can be used for both forward and inverse tone mapping.reinhardโ simple non-linear, global tone mapping algorithm. The parameter specifies the local contrast coefficient at the display peak. Essentially, a parameter of0.5implies that the reference white will be about half as bright as when clipping. Defaults to0.5, which results in the simplest formulation of this function.mobiusโ generalization of thereinhardtone mapping algorithm to support an additional linear slope near black. The tone mapping parameter indicates the trade-off between the linear section and the non-linear section. Essentially, for a given parameter x, every color value below x will be mapped linearly, while higher values get non-linearly tone-mapped. Values near1.0make this curve behave likeclip, while values near0.0make this curve behave likereinhard. The default value is0.3, which provides a good balance between colorimetric accuracy and preserving out-of-gamut details.hableโ piece-wise, filmic tone-mapping algorithm developed by John Hable for use in Uncharted 2, inspired by a similar tone-mapping algorithm used by Kodak. Popularized by its use in video games with HDR rendering. Preserves both dark and bright details very well, but comes with the drawback of changing the average brightness quite significantly. This is sort of similar toreinhardwith parameter0.24.gammaโ fits a gamma (power) function to transfer between the source and target color spaces, effectively resulting in a perceptual hard-knee joining two roughly linear sections. This preserves details at all scales fairly accurately, but can result in an image with a muted or dull appearance. The parameter is used as the cutoff point, defaulting to0.5.linearโ linearly stretches the input range to the output range, in PQ space. This will preserve all details accurately, but results in a significantly different average brightness. Can be used for inverse tone-mapping in addition to regular tone-mapping. The parameter can be used as an additional linear gain coefficient, defaulting to1.0.
tonemapping_paramโ for tunable tone mapping functions, this parameter can be used to fine-tune the curve behavior. Refer to the documentation oftonemapping. The default value of0.0is replaced by the curveโs preferred default setting.inverse_tonemappingโ if enabled, this filter will also attempt stretching SDR signals to fill HDR output color volumes. Disabled by default.tonemapping_lut_sizeโ size of the tone-mapping LUT, between2and1024. Defaults to256. Note that this figure is squared when combined withpeak_detect. ๐งฎcontrast_recoveryโ contrast recovery strength. If set to a value above0.0, the source image will be divided into high-frequency and low-frequency components, and a portion of the high-frequency image is added back onto the tone-mapped output. May cause excessive ringing artifacts for some HDR sources, but can improve the subjective sharpness and detail left over in the image after tone-mapping. Defaults to0.30.contrast_smoothnessโ contrast recovery lowpass kernel size. Defaults to3.5. Increasing or decreasing this will affect the visual appearance substantially. Has no effect whencontrast_recoveryis disabled.
โจ Dithering โจ
By default, libplacebo will dither whenever necessary, which includes rendering to any integer format below 16-bit precision. Itโs recommended to always leave this on, since not doing so may result in visible banding in the output, even if the debanding filter is enabled. If maximum performance is needed, use ordered_fixed instead of disabling dithering. No cap. ๐
ditheringโ dithering method to use. Accepts the following values:noneโ disables dithering completely. May result in visible banding. ๐blueโ dither with pseudo-blue noise. This is the default.orderedโ tunable ordered dither pattern.ordered_fixedโ faster ordered dither with a fixed size of6. Texture-less.whiteโ dither with white noise. Texture-less.
dither_lut_sizeโ dither LUT size, as log base2 between1and8. Defaults to6, corresponding to a LUT size of64x64.dither_temporalโ enables temporal dithering. Disabled by default.
๐ง Custom shaders ๐ง
libplacebo supports a number of custom shaders based on the mpv .hook GLSL syntax. A collection of such shaders can be found here:
https://github.com/mpv-player/mpv/wiki/User-Scripts#user-shaders
A full description of the mpv shader format is beyond the scope of this section, but a summary can be found here:
https://mpv.io/manual/master/#options-glsl-shader
custom_shader_pathโ specifies a path to a custom shader file to load at runtime.custom_shader_binโ specifies a complete custom shader as a raw string. ๐
๐ Debugging / performance ๐
All of the options in this section default off. They may be of assistance when attempting to squeeze the maximum performance at the cost of quality.
skip_aaโ disable anti-aliasing when downscaling.disable_linearโ disable linear light scaling.disable_builtinโ disable built-in GPU sampling (forces LUT).disable_fbosโ forcibly disable FBOs, resulting in loss of almost all functionality, but offering the maximum possible speed. Maximum speed, minimum functionality. โก
๐ซถ Commands ๐ซถ
This filter supports almost all of the above options as commands.
๐ Examples ๐
- Tone-map input to standard gamut BT.709 output:
libplacebo=colorspace=bt709:color_primaries=bt709:color_trc=bt709:range=tv
- Rescale input to fit into standard 1080p, with high quality scaling:
libplacebo=w=1920:h=1080:force_original_aspect_ratio=decrease:normalize_sar=true:upscaler=ewa_lanczos:downscaler=ewa_lanczos
- Interpolate low FPS / VFR input to smoothed constant 60 fps output:
libplacebo=fps=60:frame_mixer=mitchell_clamp
libplacebo=format=yuv420p:colorspace=bt470bg:color_primaries=bt709:color_trc=iec61966-2-1:range=pcโ convert your input to a bog-standard sRGB JPEG, iconic behavior honestlylibplacebo=deband=true:deband_iterations=3:deband_radius=8:deband_threshold=6โ higher-quality debanding settings, no cap this eatslibplacebo=upscaler=none:downscaler=none:peak_detect=falseโ run this filter on the CPU on systems with Mesa installed, with the most expensive options turned off:
ffmpeg ... -init_hw_device vulkan:llvmpipe ... -vf libplacebo=upscaler=none:downscaler=none:peak_detect=false
libplacebo=apply_filmgrain=trueโ suppress the CPU-based AV1/H.274 film grain application in the decoder and let this filter handle it instead:
ffmpeg -export_side_data +film_grain ... -vf libplacebo=apply_filmgrain=true
okay so real talk about that one ๐ this is only actually a gain if the frames are already sitting on the GPU, or if you're using libplacebo for other stuff anyway. Otherwise that VRAM roundtrip will more than offset any speedup you were hoping for. Like it will eat your whole vibe.
libplaceboโ interop with VAAPI hwdec so you dodge the round-trip through RAM:
ffmpeg -init_hw_device vulkan -hwaccel vaapi -hwaccel_output_format vaapi ... -vf libplacebo
๐ฆ libvmaf
Calculates the VMAF (Video Multi-Method Assessment Fusion) score for a reference/distorted pair of input videos. Bestie it's literally a vibe check for your video quality โจ
First input = the distorted video. Second input = the reference video. That order matters, don't flip it ๐
The VMAF score you get gets printed through the logging system.
It needs Netflix's vmaf library (libvmaf) as a prerequisite. Once you've installed the library you can enable it with:
./configure --enable-libvmaf
The filter has the following options:
modelโ a|delimited list of vmaf models. Each model can be configured with a number of parameters. Default value:version=vmaf_v0.6.1featureโ a|delimited list of features. Each feature can be configured with a number of parameters.log_pathโ sets the file path used to store log files.log_fmtโ sets the format of the log file (xml,json,csv, orsub).poolโ sets the pool method used for computing vmaf. Options aremin,harmonic_meanormean(default).n_threadsโ sets the number of threads used when initializing libvmaf. Default value:0, no threads.n_subsampleโ sets the frame subsampling interval to be used.
This filter also supports the framesync options.
โจ Examples
- In the examples below, a distorted video
distorted.mpgis compared with a reference filereference.mpg. - Basic usage:
ffmpeg -i distorted.mpg -i reference.mpg -lavfi libvmaf=log_path=output.xml -f null -
- Example with multiple models:
ffmpeg -i distorted.mpg -i reference.mpg -lavfi libvmaf='model=version=vmaf_v0.6.1\\:name=vmaf|version=vmaf_v0.6.1neg\\:name=vmaf_neg' -f null -
- Example with multiple additional features:
ffmpeg -i distorted.mpg -i reference.mpg -lavfi libvmaf='feature=name=psnr|name=ciede' -f null -
- Example with options and different containers:
ffmpeg -i distorted.mpg -i reference.mkv -lavfi "[0:v]settb=AVTB,setpts=PTS-STARTPTS[main];[1:v]settb=AVTB,setpts=PTS-STARTPTS[ref];[main][ref]libvmaf=log_fmt=json:log_path=output.json" -f null -
๐ libvmaf_cuda
This is the CUDA variant of the libvmaf filter. It only accepts CUDA frames. GPU girlies only ๐
It requires Netflix's vmaf library (libvmaf) as a prerequisite. After installing the library it can be enabled with:
./configure --enable-nonfree --enable-ffnvcodec --enable-libvmaf
๐ Examples
- Basic usage showing CUVID hardware decoding and CUDA scaling with
scale_cuda:
ffmpeg \
-hwaccel cuda -hwaccel_output_format cuda -codec:v av1_cuvid -i dis.obu \
-hwaccel cuda -hwaccel_output_format cuda -codec:v av1_cuvid -i ref.obu \
-filter_complex "
[0:v]scale_cuda=format=yuv420p[dis]; \
[1:v]scale_cuda=format=yuv420p[ref]; \
[dis][ref]libvmaf_cuda=log_fmt=json:log_path=output.json
" \
-f null -
๐ธ limitdiff
Applies a limited difference filter using a second and optionally a third video stream.
The filter accepts the following options:
thresholdโ sets the threshold used when allowing certain differences between video streams. Any absolute difference value lower than or exactly equal to this threshold will pick pixel components from the first video stream.elasticityโ sets the elasticity of soft thresholding when processing video streams. This value multiplied by the first one sets the second threshold. Any absolute difference value greater than or exactly equal to the second threshold will pick pixel components from the second video stream. For values between those two thresholds, linear interpolation between the first and second video stream will be used.referenceโ enables the reference (third) video stream processing. Disabled by default. If set, this video stream will be used for calculating absolute difference with the first video stream.planesโ specifies which planes will be processed. Defaults to all available.
Commands
This filter supports all the above options as commands except option reference.
โญ limiter
Limits the pixel component values to the specified range [min, max]. Keeping everybody inside the lines ๐ซถ
The filter accepts the following options:
minโ lower bound. Defaults to the lowest allowed value for the input.maxโ upper bound. Defaults to the highest allowed value for the input.planesโ specifies which planes will be processed. Defaults to all available.
Commands
This filter supports all the above options as commands.
๐ฅ loop
Loops video frames. Round and round we go, main character energy forever ๐
The filter accepts the following options:
loopโ sets the number of loops. Setting this value to-1will result in infinite loops. Default is0.sizeโ sets maximal size in number of frames. Default is0.startโ sets first frame of loop. Default is0.timeโ sets the time of loop start in seconds. Only used if the option namedstartis set to-1.
๐ Examples
- Loop single first frame infinitely:
loop=loop=-1:size=1:start=0
- Loop single first frame 10 times:
loop=loop=10:size=1:start=0
- Loop 10 first frames 5 times:
loop=loop=5:size=10:start=0
๐ง lut1d
Applies a 1D LUT to an input video.
The filter accepts the following options:
fileโ sets the 1D LUT file name.
Currently supported formats:
cubeโ Iridascspโ cineSpace
interpโ selects the interpolation mode.
Available values are:
nearestโ use values from the nearest defined point.linearโ interpolate values using linear interpolation.cosineโ interpolate values using cosine interpolation.cubicโ interpolate values using cubic interpolation.splineโ interpolate values using spline interpolation.
Commands
This filter supports all the above options as commands.
๐ lut3d
Applies a 3D LUT to an input video.
The filter accepts the following options:
fileโ sets the 3D LUT file name.
Currently supported formats:
3dlโ AfterEffectscubeโ Iridasdatโ DaVincim3dโ Pandoracspโ cineSpace
interpโ selects the interpolation mode.
Available values are:
nearestโ use values from the nearest defined point.trilinearโ interpolate values using the 8 points defining a cube.tetrahedralโ interpolate values using a tetrahedron.pyramidโ interpolate values using a pyramid.prismโ interpolate values using a prism.
Commands
This filter supports the interp option as commands.
๐ lumakey
Turns certain luma values into transparency. Poof, gone, bye ๐
The filter accepts the following options:
thresholdโ sets the luma which will be used as the base for transparency. Default value is0.toleranceโ sets the range of luma values to be keyed out. Default value is0.01.softnessโ sets the range of softness. Default value is0. Use this to control the gradual transition from zero to full transparency.
Commands
This filter supports the same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
๐ lut, lutrgb, lutyuv
Computes a look-up table for binding each pixel component input value to an output value, then applies it to the input video.
lutyuv applies a lookup table to a YUV input video, lutrgb to an RGB input video. Know your format bestie ๐
These filters accept the following parameters:
c0โ set first pixel component expressionc1โ set second pixel component expressionc2โ set third pixel component expressionc3โ set fourth pixel component expression, corresponds to the alpha componentrโ set red component expressiongโ set green component expressionbโ set blue component expressionaโ alpha component expressionyโ set Y/luma component expressionuโ set U/Cb component expressionvโ set V/Cr component expression
Each of them specifies the expression to use for computing the lookup table for the corresponding pixel component values.
Which exact component each of the c* options maps to depends on the format in the input.
The lut filter requires either YUV or RGB pixel formats in input, lutrgb requires RGB pixel formats in input, and lutyuv requires YUV.
The expressions can contain the following constants and functions:
w,hโ the input width and height.valโ the input value for the pixel component.clipvalโ the input value, clipped to theminval-maxvalrange.maxvalโ the maximum value for the pixel component.minvalโ the minimum value for the pixel component.negvalโ the negated value for the pixel component value, clipped to theminval-maxvalrange; it corresponds to the expressionmaxval-clipval+minval.clip(val)โ the computed value in val, clipped to theminval-maxvalrange.gammaval(gamma)โ the computed gamma correction value of the pixel component value, clipped to theminval-maxvalrange. It corresponds to the expressionpow((clipval-minval)/(maxval-minval)\,gamma)*(maxval-minval)+minval
All expressions default to clipval.
Commands
This filter supports the same commands as options.
๐ Examples
- Negate input video:
- Negate the whole thing (this is the long way of writing it, and the above is literally the same as the shorter version underneath):
lutrgb="r=maxval+minval-val:g=maxval+minval-val:b=maxval+minval-val"
lutyuv="y=maxval+minval-val:u=maxval+minval-val:v=maxval+minval-val"
The above is the same as:
lutrgb="r=negval:g=negval:b=negval"
lutyuv="y=negval:u=negval:v=negval"
- Negate luma only, bestie:
lutyuv=y=negval
- Remove chroma components, turning the video into a graytone image (vibes: colorless but chic):
lutyuv="u=128:v=128"
- Apply a luma burning effect ๐ฅ:
lutyuv="y=2*val"
- Remove green and blue components:
lutrgb="g=0:b=0"
- Set a constant alpha channel value on input:
format=rgba,lutrgb=a="maxval-minval/2"
- Correct luma gamma by a factor of 0.5:
lutyuv=y=gammaval(0.5)
- Discard least significant bits of luma:
lutyuv=y='bitand(val, 128+64+32)'
- Technicolor like effect โจ:
lutyuv=u='(val-maxval/2)*2+maxval/2':v='(val-maxval/2)*2+maxval/2'
lut2, tlut2
The lut2 filter takes two input streams and outputs one stream. Iconic two-in-one-stream behavior, honestly.
The tlut2 (time lut2) filter takes two consecutive frames from one single stream. Same energy, but it's pulling from time instead of a second input.
This filter accepts the following parameters:
c0โ set first pixel component expressionc1โ set second pixel component expressionc2โ set third pixel component expressionc3โ set fourth pixel component expression, corresponds to the alpha componentdโ set output bit depth, only available for thelut2filter. By default is0, which means bit depth is automatically picked from first input format.
The lut2 filter also supports the framesync options.
Each of them specifies the expression to use for computing the lookup table for the corresponding pixel component values.
The exact component associated to each of the c* options depends on the format in inputs.
The expressions can contain the following constants:
w,hโ The input width and height.xโ The first input value for the pixel component.yโ The second input value for the pixel component.bdxโ The first input video bit depth.bdyโ The second input video bit depth.
All expressions default to x.
Commands
This filter supports the all above options as commands except option d.
Examples
- Highlight differences between two RGB video streams:
lut2='ifnot(x-y,0,pow(2,bdx)-1):ifnot(x-y,0,pow(2,bdx)-1):ifnot(x-y,0,pow(2,bdx)-1)'
- Highlight differences between two YUV video streams:
lut2='ifnot(x-y,0,pow(2,bdx)-1):ifnot(x-y,pow(2,bdx-1),pow(2,bdx)-1):ifnot(x-y,pow(2,bdx-1),pow(2,bdx)-1)'
- Show max difference between two video streams:
lut2='if(lt(x,y),0,if(gt(x,y),pow(2,bdx)-1,pow(2,bdx-1))):if(lt(x,y),0,if(gt(x,y),pow(2,bdx)-1,pow(2,bdx-1))):if(lt(x,y),0,if(gt(x,y),pow(2,bdx)-1,pow(2,bdx-1)))'
maskedclamp
Clamp the first input stream with the second input and third input stream. Three streams, one very opinionated clamp ๐ซถ
Returns the value of first stream to be between second input stream - undershoot and third input stream + overshoot.
This filter accepts the following options:
undershootโ Default value is0.overshootโ Default value is0.planesโ Set which planes will be processed as bitmap, unprocessed planes will be copied from first stream. By default value0xf, all planes will be processed.
Commands
This filter supports the all above options as commands.
maskedmax
Merge the second and third input stream into output stream using absolute differences between second input stream and first input stream and absolute difference between third input stream and first input stream. The picked value will be from second input stream if second absolute difference is greater than first one or from third input stream otherwise.
This filter accepts the following options:
planesโ Set which planes will be processed as bitmap, unprocessed planes will be copied from first stream. By default value0xf, all planes will be processed.
Commands
This filter supports the all above options as commands.
maskedmerge
Merge the first input stream with the second input stream using per pixel weights in the third input stream. It's giving blend era ๐
A value of 0 in the third stream pixel component means that pixel component from first stream is returned unchanged, while maximum value (eg. 255 for 8-bit videos) means that pixel component from second stream is returned unchanged. Intermediate values define the amount of merging between both input stream's pixel components.
This filter accepts the following options:
planesโ Set which planes will be processed as bitmap, unprocessed planes will be copied from first stream. By default value0xf, all planes will be processed.
Commands
This filter supports the all above options as commands.
maskedmin
Merge the second and third input stream into output stream using absolute differences between second input stream and first input stream and absolute difference between third input stream and first input stream. The picked value will be from second input stream if second absolute difference is less than first one or from third input stream otherwise.
This filter accepts the following options:
planesโ Set which planes will be processed as bitmap, unprocessed planes will be copied from first stream. By default value0xf, all planes will be processed.
Commands
This filter supports the all above options as commands.
maskedthreshold
Pick pixels comparing absolute difference of two video streams with fixed threshold. Like a little pixel doorman lowkey ๐ช
If absolute difference between pixel component of first and second video stream is equal or lower than user supplied threshold than pixel component from first video stream is picked, otherwise pixel component from second video stream is picked.
This filter accepts the following options:
thresholdโ Set threshold used when picking pixels from absolute difference from two input video streams.planesโ Set which planes will be processed as bitmap, unprocessed planes will be copied from second stream. By default value0xf, all planes will be processed.modeโ Set mode of filter operation. Can beabsordiff. Default isabs.
Commands
This filter supports the all above options as commands.
maskfun
Create mask from input video. Masks are literally so aesthetic, no notes.
For example it is useful to create motion masks after tblend filter.
This filter accepts the following options:
lowโ Set low threshold. Any pixel component lower or exact than this value will be set to0.highโ Set high threshold. Any pixel component higher than this value will be set to max value allowed for current pixel format.planesโ Set planes to filter, by default all available planes are filtered.fillโ Fill all frame pixels with this value.sumโ Set max average pixel value for frame. If sum of all pixel components is higher that this average, output frame will be completely filled with value set by fill option. Typically useful for scene changes when used in combination withtblendfilter.
Commands
This filter supports the all above options as commands.
mcdeint
Apply motion-compensation deinterlacing. Deinterlacing but make it fancy โจ
It needs one field per frame as input and must thus be used together with yadif=1/3 or equivalent.
This filter accepts the following options:
modeโ Set the deinterlacing mode.
It accepts one of the following values:
fastmediumslowโ use iterative motion estimationextra_slowโ likeslow, but use multiple reference frames.
Default value is fast.
parityโ Set the picture field parity assumed for the input video. It must be one of the following values:0,tffโ assume top field first1,bffโ assume bottom field first
Default value is bff.
qpโ Set per-block quantization parameter (QP) used by the internal encoder.
Higher values should result in a smoother motion vector field but less optimal individual vectors. Default value is 1.
median
Pick median pixel from certain rectangle defined by radius. Median filter said "I'm the main character" and honestly? Correct.
This filter accepts the following options:
radiusโ Set horizontal radius size. Default value is1. Allowed range is integer from1to127.planesโ Set which planes to process. Default is15, which is all available planes.radiusVโ Set vertical radius size. Default value is0. Allowed range is integer from0to127. If it is0, value will be picked from horizontalradiusoption.percentileโ Set median percentile. Default value is0.5. Default value of0.5will pick always median values, while0will pick minimum values, and1maximum values.
Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
mergeplanes
Merge color channel components from several video streams. Channel mixing is the group project and everybody's pulling their weight ๐
The filter accepts up to 4 input streams, and merge selected input planes to the output video.
This filter accepts the following options:
mappingโ Set input to output plane mapping. Default is0.
The mappings is specified as a bitmap. It should be specified as a hexadecimal number in the form 0xAa[Bb[Cc[Dd]]]. Aa describes the mapping for the first plane of the output stream. A sets the number of the input stream to use (from 0 to 3), and a the plane number of the corresponding input to use (from 0 to 3). The rest of the mappings is similar, Bb describes the mapping for the output stream second plane, Cc describes the mapping for the output stream third plane and Dd describes the mapping for the output stream fourth plane.
formatโ Set output pixel format. Default isyuva444p.map0s,map1s,map2s,map3sโ Set input to output stream mapping for output Nth plane. Default is0.map0p,map1p,map2p,map3pโ Set input to output plane mapping for output Nth plane. Default is0.
Examples
- Merge three gray video streams of same width and height into single video stream:
[a0][a1][a2]mergeplanes=0x001020:yuv444p
- Merge 1st
yuv444pstream and 2nd gray video stream intoyuva444pvideo stream:
[a0][a1]mergeplanes=0x00010210:yuva444p
- Swap Y and A plane in
yuva444pstream: format=yuva444p,mergeplanes=0x03010200:yuva444p- Swap U and V plane in yuv420p stream:
format=yuv420p,mergeplanes=0x000201:yuv420p
- Cast a rgb24 clip to yuv444p:
format=rgb24,mergeplanes=0x000102:yuv444p
๐ธ mestimate
Bestie, this one estimates and exports motion vectors using block matching algorithms, and then it stashes those motion vectors in frame side data so other filters can come and use them. โจ
This filter accepts the following options:
methodโ tell it which motion estimation method to use. It takes one of these values:esaโ Exhaustive search algorithm.tssโ Three step search algorithm.tdlsโ Two dimensional logarithmic search algorithm.ntssโ New three step search algorithm.fssโ Four step search algorithm.dsโ Diamond search algorithm.hexbsโ Hexagon-based search algorithm.epzsโ Enhanced predictive zonal search algorithm.umhโ Uneven multi-hexagon search algorithm.
Default value is esa.
mb_sizeโ Macroblock size. Default16.search_paramโ Search parameter. Default7.
๐ mestimate_d3d12
Okay so this is the glow-up version of mestimate โ it estimates and exports motion vectors too, but using D3D12 hardware-accelerated motion estimation. ๐ It's leveraging the GPU hardware motion estimation capabilities that live in the DirectX 12 Video APIs, and that's how it scores significant performance improvements over the software-based mestimate filter.
Motion vectors get stored in frame side data so other filters can use them, same deal.
Heads up bestie: this filter requires the input to be in d3d12 hardware pixel format. And it uses quarter-pixel precision for motion vector estimation. No cap.
This filter accepts the following options:
mb_sizeโ Macroblock size. Only8and16are supported. Default16.
Example
Estimate motion vectors using D3D12 hardware acceleration with 16x16 blocks, and visualize them:
ffmpeg -hwaccel d3d12va -hwaccel_output_format d3d12 -i input.mp4 \
-vf mestimate_d3d12=mb_size=16,hwdownload,format=nv12,codecview=mv=pf \
-c:v libx264 -preset fast -b:v 5M output.mp4
๐ฆ midequalizer
This filter applies the Midway Image Equalization effect using two video streams. Iconic. ๐
So what Midway Image Equalization does is adjust a pair of images so they have the same histogram, all while keeping their dynamics as intact as possible. It's lowkey perfect for stuff like matching exposures from a pair of stereo cameras. ๐ธ
This filter has two inputs and one output, and those inputs must be the same pixel format โ but they can be different sizes, slay. The output of the filter is the first input, adjusted with the midway histogram of both inputs.
This filter accepts the following option:
planesโ Set which planes to process. Default is15, which is literally all available planes. โจ
๐ minterpolate
Convert the video to the specified frame rate using motion interpolation. Periodt.
This filter accepts the following options:
fpsโ Specify the output frame rate. This can be rational, e.g.60000/1001. Frames are dropped iffpsis lower than source fps. Default60.mi_modeโ Motion interpolation mode. Following values are accepted:dupโ Duplicate previous or next frame for interpolating new ones.blendโ Blend source frames. Interpolated frame is mean of previous and next frames.mciโ Motion compensated interpolation. Following options are effective when this mode is selected:mc_modeโ Motion compensation mode. Following values are accepted:obmcโ Overlapped block motion compensation.aobmcโ Adaptive overlapped block motion compensation. Window weighting coefficients are controlled adaptively according to the reliabilities of the neighboring motion vectors to reduce oversmoothing.
Default mode is obmc.
me_modeโ Motion estimation mode. Following values are accepted:bidirโ Bidirectional motion estimation. Motion vectors are estimated for each source frame in both forward and backward directions.bilatโ Bilateral motion estimation. Motion vectors are estimated directly for interpolated frame.
Default mode is bilat.
meโ The algorithm to be used for motion estimation. Following values are accepted:esaโ Exhaustive search algorithm.tssโ Three step search algorithm.tdlsโ Two dimensional logarithmic search algorithm.ntssโ New three step search algorithm.fssโ Four step search algorithm.dsโ Diamond search algorithm.hexbsโ Hexagon-based search algorithm.epzsโ Enhanced predictive zonal search algorithm.umhโ Uneven multi-hexagon search algorithm.
Default algorithm is epzs.
mb_sizeโ Macroblock size. Default16.search_paramโ Motion estimation search parameter. Default32.vsbmcโ Enable variable-size block motion compensation. Motion estimation is applied with smaller block sizes at object boundaries in order to make them less blurry. Default is0(disabled).
scdโ Scene change detection method. Scene change leads motion vectors to be in random direction, and scene change detection replaces interpolated frames by duplicate ones. May not be needed for other modes. Following values are accepted:noneโ Disable scene change detection.fdiffโ Frame difference. Corresponding pixel values are compared and if it satisfiesscd_thresholdscene change is detected.
Default method is fdiff.
scd_thresholdโ Scene change detection threshold. Default is10..
๐ mix
Mix several video input streams into one video stream. It's giving collab. ๐
A description of the accepted options follows.
inputsโ The number of inputs. If unspecified, it defaults to2.weightsโ Specify weight of each input video stream as sequence. Each weight is separated by space. If the number of weights is smaller than the number of frames, the last specified weight will be used for all remaining unset weights.scaleโ Specify scale. If it is set, it will be multiplied with the sum of each weight multiplied with pixel values to give the final destination pixel value. By default scale is auto scaled to sum of weights.planesโ Set which planes to filter. Default is all. Allowed range is from0to15.durationโ Specify how end of stream is determined.longestโ The duration of the longest input. (default)shortestโ The duration of the shortest input.firstโ The duration of the first input.
Commands
This filter supports the following commands:
weightsscaleplanes
Syntax is same as option with same name. ๐ซถ
โญ monochrome
Convert video to gray using a custom color filter. Main character energy honestly.
A description of the accepted options follows.
cbโ Set the chroma blue spot. Allowed range is from-1to1. Default value is0.crโ Set the chroma red spot. Allowed range is from-1to1. Default value is0.sizeโ Set the color filter size. Allowed range is from.1to10. Default value is1.highโ Set the highlights strength. Allowed range is from0to1. Default value is0.
Commands
This filter supports all above options as commands. ๐
๐ง morpho
Okay so this filter lets you apply the main morphological grayscale transforms โ erode and dilate โ with arbitrary structures set in a second input stream.
And bestie, unlike the naive implementation which is much slower with erosion and dilation filters, when speed is critical you should use the morpho filter instead. Not me hyping it up but it's literally the move. ๐ฅ
A description of accepted options follows,
modeโ Set morphological transform to apply, can be:erodedilateopenclosegradienttophatblackhat
Default is erode.
planesโ Set planes to filter. By default all planes except alpha are filtered.structureโ Set which structure video frames will be processed from second input stream, can befirstorall. Default isall.
The morpho filter also supports the framesync options.
Commands
This filter supports same commands as options.
๐ mpdecimate
Drop frames that do not differ greatly from the previous frame, in order to reduce frame rate. Bye bye redundant frames. ๐
The main use of this filter is for very-low-bitrate encoding (e.g. streaming over dialup modem โ yes, we're going back in time ๐), but it could in theory be used for fixing movies that were inverse-telecined incorrectly.
A description of the accepted options follows.
maxโ Set the maximum number of consecutive frames which can be dropped (if positive), or the minimum interval between dropped frames (if negative). If the value is0, the frame is dropped disregarding the number of previous sequentially dropped frames.
Default value is 0.
keepโ Set the maximum number of consecutive similar frames to ignore before starting to drop them. If the value is0, the frame is dropped disregarding the number of previous sequentially similar frames.
Default value is 0.
hi,lo,fracโ Set the dropping threshold values.
Values for hi and lo are for 8x8 pixel blocks and represent actual pixel value differences, so a threshold of 64 corresponds to 1 unit of difference for each pixel, or the same spread out differently over the block.
A frame is a candidate for dropping if no 8x8 blocks differ by more than a threshold of hi, and if no more than frac blocks (1 meaning the whole image) differ by more than a threshold of lo.
Default value for hi is 64*12, default value for lo is 64*5, and default value for frac is 0.33.
๐ msad
Obtain the MSAD (Mean Sum of Absolute Differences) between two input videos. Fr fr, that's what it does.
This filter takes two input videos.
Both input videos must have the same resolution and pixel format for this filter to work correctly. It also assumes that both inputs have the same number of frames, which are compared one by one.
The obtained per component, average, min and max MSAD is printed through the logging system. ๐
The filter stores the calculated MSAD of each frame in frame metadata.
This filter also supports the framesync options. โจ
ffmpeg -i main.mpg -i ref.mpg -lavfi msad -f null -
Like, that's the whole vibe โ main character main.mpg gets compared against the reference girlie ref.mpg, no cap. โจ
multiply
Multiply the pixel values of the first video stream by the pixel values of the second video stream. Math but make it cinema. ๐ฅ
She accepts these options:
scaleโ sets the scale that gets applied to the second video stream. Default is1. Allowed range goes from0to9.offsetโ sets the offset applied to the second video stream. Default is0.5. Allowed range is-1to1.planesโ specify which planes from the input video stream get processed. By default, all planes are processed, she's not picking favorites.
Commands
This filter supports the same commands as options. ๐
negate
Negate (aka invert) the input video. Yes it's giving photo-negative, and yes it ate.
It accepts this option:
componentsโ set which components to negate.
Available values for components are:
yuvargbnegate_alphaโ with value1, it negates the alpha component, if present. Default value is0. ๐ซถ
Commands
This filter supports the same commands as options.
nlmeans
Denoise your frames using the Non-Local Means algorithm. Basically she looks around for pixels with similar contexts and adjusts each pixel accordingly โ very "you're not alone bestie" of her. ๐ธ
That context similarity is defined by comparing their surrounding patches of size pxp. Patches get searched in an area of rxr around the pixel.
Heads up: the research area defines centers for patches, which means some patches will be made of pixels outside that research area. Not a bug, just how she rolls.
The filter accepts the following options.
sโ set denoising strength. Default is1.0. Must be in range[1.0, 30.0].pโ set patch size. Default is7. Must be an odd number in range[0, 99].pcโ same aspbut for the chroma planes. The default value is0and means automatic.rโ set research size. Default is15. Must be an odd number in range[0, 99].rcโ same asrbut for the chroma planes. The default value is0and means automatic.
nnedi
Deinterlace video using neural network edge directed interpolation. Neural net but for your interlaced mess, slay. ๐ง โจ
This filter accepts the following options:
weightsโ mandatory option, without the binary file the filter literally cannot work. Currently the file can be found here:https://github.com/dubhater/vapoursynth-nnedi3/blob/master/src/nnedi3_weights.bindeintโ set which frames to deinterlace, by default it is"all". Can be"all"or"interlaced".fieldโ set the mode of operation.
Can be one of the following:
afโ use frame flags, both fields.aโ use frame flags, single field.tโ use top field only.bโ use bottom field only.tfโ use both fields, top first.bfโ use both fields, bottom first.
planesโ set which planes to process, by default the filter processes all frames.nsizeโ set the size of the local neighborhood around each pixel, used by the predictor neural network.
Can be one of the following:
s8x6s16x6s32x6s48x6s8x4s16x4s32x4
nnsโ set the number of neurons in the predictor neural network. Can be one of the following:n16n32n64n128n256
qualโ controls the number of different neural network predictions that get blended together to compute the final output value. Can be"fast", default, or"slow".etypeโ set which set of weights to use in the predictor. Can be one of the following:a,absโ weights trained to minimize absolute errors,mseโ weights trained to minimize squared error
pscrnโ controls whether or not the prescreener neural network gets used to decide which pixels should be processed by the predictor neural network and which can be handled by simple cubic interpolation. The prescreener is trained to know whether cubic interpolation will be sufficient for a pixel or whether it should be predicted by the predictor nn. The computational complexity of the prescreener nn is much less than that of the predictor nn. Since most pixels can be handled by cubic interpolation, using the prescreener generally results in much faster processing. The prescreener is pretty accurate, so the difference between using it and not using it is almost always unnoticeable.
Can be one of the following:
noneoriginalnewnew2new3
Default is "new".
Commands
This filter supports the same commands as options, excluding the weights option. ๐
noformat
Force libavfilter to not use any of the specified pixel formats for the input to the next filter. It's giving "girl, literally anything but those." ๐
It accepts the following parameters:
pix_fmtsโ a'|'-separated list of pixel format names, such aspix_fmts=yuv420p|monow|rgb24".
Examples
- Force libavfilter to use a format different from
yuv420pfor the input to thevflipfilter:
noformat=pix_fmts=yuv420p,vflip
- Convert the input video to any of the formats not contained in the list:
noformat=yuv420p|yuv444p|yuv410p
noise
Add noise on the video input frame. Chaos sprinkled on purpose, we love to see it. ๐
The filter accepts the following options:
all_seed,c0_seed,c1_seed,c2_seed,c3_seedโ set the noise seed for a specific pixel component, or for all pixel components in the case ofall_seed. Default value is123457.all_strength,alls,c0_strength,c0s,c1_strength,c1s,c2_strength,c2s,c3_strength,c3sโ set noise strength for a specific pixel component, or for all pixel components in the case ofall_strength. Default value is0. Allowed range is[0, 100].all_flags,allf,c0_flags,c0f,c1_flags,c1f,c2_flags,c2f,c3_flags,c3fโ set pixel component flags, or set flags for all components in the case ofall_flags.
Available values for component flags are:
aโ averaged temporal noise (smoother)pโ mix random noise with a (semi)regular patterntโ temporal noise (noise pattern changes between frames)uโ uniform noise (gaussian otherwise)
Examples
Add temporal and uniform noise to the input video:
noise=alls=20:allf=t+u
normalize
Normalize RGB video (aka histogram stretching, contrast stretching). See: https://en.wikipedia.org/wiki/Normalization_(image_processing) โ she's academic AND cute. ๐๐
For each channel of each frame, the filter computes the input range and maps it linearly to the user-specified output range. The output range defaults to the full dynamic range from pure black to pure white.
Temporal smoothing can be used on the input range to reduce flickering (rapid changes in brightness) caused when small dark or bright objects enter or leave the scene. This is similar to the auto-exposure (automatic gain control) on a video camera, and, like a video camera, it may cause a period of over- or under-exposure of the video. ๐ญ
The R,G,B channels can be normalized independently, which may cause some color shifting, or linked together as a single channel, which prevents color shifting. Linked normalization preserves hue. Independent normalization does not, so it can be used to remove some color casts. Independent and linked normalization can be combined in any ratio.
The normalize filter accepts the following options:
blackpt,whiteptโ colors which define the output range. The minimum input value is mapped to theblackpt. The maximum input value is mapped to thewhitept. The defaults areblackandwhiterespectively. Specifyingwhiteforblackptandblackforwhiteptwill give color-inverted, normalized video. Shades of grey can be used to reduce the dynamic range (contrast). Specifying saturated colors here can create some interesting effects. ๐smoothingโ the number of previous frames to use for temporal smoothing. The input range of each channel is smoothed using a rolling average over the current frame and thesmoothingprevious frames. The default is0(no temporal smoothing).independenceโ controls the ratio of independent (color shifting) channel normalization to linked (color preserving) normalization.0.0is fully linked,1.0is fully independent. Defaults to1.0(fully independent).strengthโ overall strength of the filter.1.0is full strength.0.0is a rather expensive no-op. Defaults to1.0(full strength).
Commands
This filter supports the same commands as options, excluding the smoothing option. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
Examples
Stretch video contrast to use the full dynamic range, with no temporal smoothing; may flicker depending on the source content:
normalize=blackpt=black:whitept=white:smoothing=0
As above, but with 50 frames of temporal smoothing; flicker should be reduced, depending on the source content:
normalize=blackpt=black:whitept=white:smoothing=50
As above, but with hue-preserving linked channel normalization:
normalize=blackpt=black:whitept=white:smoothing=50:independence=0
As above, but with half strength:
normalize=blackpt=black:whitept=white:smoothing=50:independence=0:strength=0.5
Map the darkest input color to red, the brightest input color to cyan:
normalize=blackpt=red:whitept=cyan
null
Pass the video source unchanged to the output. She does nothing and she does it flawlessly. ๐
ocio
OpenColorIO library filter. ๐
This filter allows you to do color management using the OpenColorIO library. See https://opencolorio.org/ for more details. To enable compilation of this filter, you need to configure FFmpeg with --enable-libopencolorio.
It accepts the following options:
configโ by default the filter will use the OCIO config defined by theOCIOenvironment variable, but this parameter allows you to explicitly specify its location. If you are getting started, you can useconfig=ocio://studio-config-v1.0.0_aces-v1.3_ocio-v2.1which specifies one of the built in defaults. โจinputโ set the input colorspace.outputโ set the output colorspace.displayโ set the display colorspace, used in combination withview.viewโ set the view colorspace, used in combination withdisplay.inverseโ when used in combination withdisplayandview, this inverts the transform, so going from a display/view to the"input colorspace". ๐ฆfiletransformโ lets you point at an external file-transform to use instead of the OCIO config file. Super handy when you just wanna apply one single transform without dragging a whole OCIO config along. โจformatโ lets you set the output pix_fmt of the OCIO filter. Heads up bestie, this has to be an RGB colorspace, so you're genuinely limited torgb24,rgba,rgb48,rgba48,gbrp10,gbrp12,gbrpf32le,gbrapf32le. For most encoding we'd recommendrgb48. ๐context_paramsโ lets you specify extra context parameters for the OCIO filter. It's a list ofkey=valuepairs, separated by colons. Easy.
Examples
Map from ACEScg to ACEScct โ this assumes the OCIO file is defined with the OCIO environment variable.
input=ACEScg:output=ACEScct:format=rgb48
Map from ACEScg to a sRGB display using the "ACES 1.0 - SDR Video" view transform โ again, this assumes the OCIO file is defined with the OCIO environment variable. Note that you'll need to wrap the argument in quotes so the spaces get interpreted correctly, no cap:
input=ACEScg:display=sRGB - Display:view=ACES 1.0 - SDR Video:format=rgb48
Same vibe as above, but using the OCIO file studio-config-v1.0.0_aces-v1.3_ocio-v2.1_ns.ocio instead of the OCIO environment variable:
config=studio-config-v1.0.0_aces-v1.3_ocio-v2.1_ns.ocio:input=ACEScg:display=sRGB - Display:view=ACES 1.0 - SDR Video:format=rgb48
If you're converting to YCrCb you still wanna set the color matrix for the conversion โ this one is a genuinely good example of combining the two. ๐ฅ
ffmpeg -y -i SOURCEFRAMES.%05d.exr -c:v libx265 -vf "ocio=input=ACEScg:output=ACEScct:format=rgb48,scale=in_color_matrix=bt709:out_color_matrix=bt709,format=yuv444p10" OUTPUTFILE.mov
ocr
Optical Character Recognition โ yes, literally reading text out of your frames. ๐
This filter uses Tesseract for optical character recognition. To enable compilation of this filter, you need to configure FFmpeg with --enable-libtesseract.
It accepts the following options:
datapathโ setdatapathto tesseract data. Default is to use whatever was set at installation.languageโ set language, default is"eng".whitelistโ set character whitelist.blacklistโ set character blacklist.
The filter exports recognized text as the frame metadata lavfi.ocr.text. It also exports the confidence of recognized words as the frame metadata lavfi.ocr.confidence. Cute, right? ๐ซถ
ocv
Apply a video transform using libopencv.
To enable this filter, install the libopencv library and headers and configure FFmpeg with --enable-libopencv.
It accepts the following parameters:
filter_nameโ the name of the libopencv filter to apply.filter_paramsโ the parameters to pass to the libopencv filter. If not specified, the default values are assumed.
Refer to the official libopencv documentation for more precise info: <http://docs.opencv.org/master/modules/imgproc/doc/filtering.html>
Several libopencv filters are supported โ see the following subsections. ๐ฆ
dilate
Dilate an image by using a specific structuring element. It corresponds to the libopencv function cvDilate.
It accepts the parameters: struct_el|nb_iterations.
struct_el represents a structuring element, and has the syntax: colsxrows+anchor_xxanchor_y/shape
cols and rows represent the number of columns and rows of the structuring element, anchor_x and anchor_y the anchor point, and shape the shape for the structuring element. shape must be "rect", "cross", "ellipse", or "custom".
If the value for shape is "custom", it must be followed by a string of the form "=filename". The file with name filename is assumed to represent a binary image, with each printable character corresponding to a bright pixel. When a custom shape is used, cols and rows are ignored โ the number of columns and rows of the read file are assumed instead. ๐คฏ
The default value for struct_el is "3x3+0x0/rect".
nb_iterations specifies the number of times the transform is applied to the image, and defaults to 1.
Some examples:
# Use the default values
ocv=dilate
# Dilate using a structuring element with a 5x5 cross, iterating two times
ocv=filter_name=dilate:filter_params=5x5+2x2/cross|2
# Read the shape from the file diamond.shape, iterating two times.
# The file diamond.shape may contain a pattern of characters like this
# *
# ***
# *****
# ***
# *
# The specified columns and rows are ignored
# but the anchor point coordinates are not
ocv=dilate:0x0+2x2/custom=diamond.shape|2
erode
Erode an image by using a specific structuring element. It corresponds to the libopencv function cvErode.
It accepts the parameters: struct_el:nb_iterations, with the same syntax and semantics as the dilate filter. (Yes, the separator is a colon here โ do not come for me, that's just how it is. ๐)
smooth
Smooth the input video.
The filter takes the following parameters: type|param1|param2|param3|param4.
type is the type of smooth filter to apply, and must be one of these values: "blur", "blur_no_scale", "median", "gaussian", or "bilateral". The default value is "gaussian".
The meaning of param1, param2, param3, and param4 depends on the smooth type. param1 and param2 accept integer positive values or 0. param3 and param4 accept floating point values.
The default value for param1 is 3. The default value for the other parameters is 0.
These parameters correspond to the parameters assigned to the libopencv function cvSmooth.
oscilloscope
2D Video Oscilloscope. ๐
Useful to measure spatial impulse, step responses, chroma delays, etc.
It accepts the following parameters:
xโ set scope center x position.yโ set scope center y position.sโ set scope size, relative to frame diagonal.tโ set scope tilt/rotation.oโ set trace opacity.txโ set trace center x position.tyโ set trace center y position.twโ set trace width, relative to width of frame.thโ set trace height, relative to height of frame.cโ set which components to trace. By default it traces first three components.gโ draw trace grid. By default is enabled.stโ draw some statistics. By default is enabled.scโ draw scope. By default is enabled.
Commands
This filter supports same commands as options. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
Examples
- Inspect full first row of video frame. ๐
oscilloscope=x=0.5:y=0:s=1
- Inspect full last row of video frame.
oscilloscope=x=0.5:y=1:s=1
- Inspect full 5th line of video frame of height 1080.
oscilloscope=x=0.5:y=5/1080:s=1
- Inspect full last column of video frame.
oscilloscope=x=1:y=0.5:s=1:t=1
overlay
Overlay one video on top of another. Literal main character energy โ one video is the moment, the other is the accessory. ๐
It takes two inputs and has one output. The first input is the "main" video on which the second input is overlaid.
It accepts the following parameters:
A description of the accepted options follows.
x,yโ set the expression for the x and y coordinates of the overlaid video on the main video. Default value is"0"for both expressions. In case the expression is invalid, it is set to a huge value (meaning that the overlay will not be displayed within the output visible area). ๐ญeof_actionโ see framesync.evalโ set when the expressions forx, andyare evaluated. It accepts the following values:initโ only evaluate expressions once during the filter initialization or when a command is processedframeโ evaluate expressions for each incoming frame- Default value is
frame.
shortestโ see framesync.formatโ set the format for the output video. It accepts the following values:yuv420โ force YUV 4:2:0 8-bit planar outputyuv420p10โ force YUV 4:2:0 10-bit planar outputyuv422โ force YUV 4:2:2 8-bit planar outputyuv422p10โ force YUV 4:2:2 10-bit planar outputyuv444โ force YUV 4:4:4 8-bit planar outputyuv444p10โ force YUV 4:4:4 10-bit planar outputrgbโ force RGB 8-bit packed outputgbrpโ force RGB 8-bit planar outputautoโ automatically pick format- Default value is
yuv420.
repeatlastโ see framesync.alphaโ set format of alpha of the overlaid video, it can bestraightorpremultiplied, orautoto choose the alpha mode automatically. Default isauto.
The x, and y expressions can contain the following parameters.
main_w,Wandmain_h,Hโ the main input width and height.overlay_w,wandoverlay_h,hโ the overlay input width and height.x,yโ the computed values forxandy. They are evaluated for each new frame.hsub,vsubโ horizontal and vertical chroma subsample values of the output format. For example for the pixel format"yuv422p"hsubis2andvsubis1.nโ the number of input frame, starting from0posโ the position in the file of the input frame,NANif unknown; deprecated, do not use. (Like, genuinely don't. It's giving "why is this still here." ๐)tโ the timestamp, expressed in seconds. It'sNANif the input timestamp is unknown.
This filter also supports the framesync options.
Note that the n, t variables are available only when evaluation is done per frame, and will evaluate to NAN when eval is set to init.
Be aware that frames are taken from each input video in timestamp order, hence, if their initial timestamps differ, it is a good idea to pass the two inputs through a setpts=PTS-STARTPTS filter to have them begin in the same zero timestamp, as the example for the movie filter does. ๐ฐ๏ธ
You can chain together more overlays but you should test the efficiency of such approach.
Commands
This filter supports the following commands:
x,yโ modify thexandyof the overlay input. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value.
Examples
- Draw the overlay at 10 pixels from the bottom right corner of the main video: ๐ธ
overlay=main_w-overlay_w-10:main_h-overlay_h-10
Using named options the example above becomes:
overlay=x=main_w-overlay_w-10:y=main_h-overlay_h-10
- Insert a transparent PNG logo in the bottom left corner of the input, using the
ffmpegtool with the-filter_complexoption:
โฆand here's the code for the logo-drop, bestie ๐
ffmpeg -i input -i logo -filter_complex 'overlay=10:main_h-overlay_h-10' output
- Insert 2 different transparent PNG logos (second logo on bottom right corner) using the ffmpeg tool: โ yes, two logos, two overlays, one command, iconic:
ffmpeg -i input -i logo1 -i logo2 -filter_complex 'overlay=x=10:y=H-h-10,overlay=x=W-w-10:y=H-h-10' output
- Add a transparent color layer on top of the main video;
WxHmust specify the size of the main input to the overlay filter โ so like,WxHis literally the size of your main input, no improvising:
color=color=red@.3:size=WxH [over]; [in][over] overlay [out]
- Play an original video and a filtered version (here with the
deshakefilter) side by side using the ffplay tool โ split screen moment fr fr:
ffplay input.avi -vf 'split[a][b]; [a]pad=iw*2:ih[src]; [b]deshake[filt]; [src][filt]overlay=w'
The above command is the same as:
ffplay input.avi -vf 'split[b], pad=iw*2[src], [b]deshake, [src]overlay=w'
- Make a sliding overlay appearing from the left to the right top part of the screen starting since time 2 โ entrance? served. โจ
overlay=x='if(gte(t,2), -w+(t-2)*20, NAN)':y=0
- Compose output by putting two input videos side to side โ the split-screen collage of your dreams:
ffmpeg -i left.avi -i right.avi -filter_complex "
nullsrc=size=200x100 [background];
[0:v] setpts=PTS-STARTPTS, scale=100x100 [left];
[1:v] setpts=PTS-STARTPTS, scale=100x100 [right];
[background][left] overlay=shortest=1 [background+left];
[background+left][right] overlay=shortest=1:x=100 [left+right]
"
- Mask 10-20 seconds of a video by applying the
delogofilter to a section โ censoring era ๐ซฃ:
ffmpeg -i test.avi -codec:v:0 wmv2 -ar 11025 -b:v 9000k
-vf '[in]split[split_main][split_delogo];[split_delogo]trim=start=360:end=371,delogo=0:0:640:480[delogoed];[split_main][delogoed]overlay=eof_action=pass[out]'
masked.avi
- Chain several overlays in cascade โ overlay-ception, and honestly? ate:
nullsrc=s=200x200 [bg];
testsrc=s=100x100, split=4 [in0][in1][in2][in3];
[in0] lutrgb=r=0, [bg] overlay=0:0 [mid0];
[in1] lutrgb=g=0, [mid0] overlay=100:0 [mid1];
[in2] lutrgb=b=0, [mid1] overlay=0:100 [mid2];
[in3] null, [mid2] overlay=100:100 [out0]
๐ owdenoise
Apply Overcomplete Wavelet denoiser โ it's giving "smooth out the noise but keep the vibes" energy.
The filter accepts the following options:
depthโ sets the depth. Larger depth values will denoise lower frequency components more, but slow down filtering. Must be anintin the range8-16, default is8. (So yeah, more denoise = more waiting, lowkey the tradeoff of all time.)luma_strength,lsโ sets the luma strength. Must be adoublevalue in the range0-1000, default is1.0.chroma_strength,csโ sets the chroma strength. Must be adoublevalue in the range0-1000, default is1.0.
๐ผ๏ธ pad
Adds paddings to the input image, and places the original input at the provided x, y coordinates. It's the frame around the picture, bestie โ the matte, the border, the whole presentation. ๐
It accepts the following parameters:
width,wheight,hโ Specify an expression for the size of the output image with the paddings added. If the value forwidthorheightis0, the corresponding input size is used for the output.
The width expression can reference the value set by the height expression, and vice versa. (They're gossip besties, they know each other's business.)
The default value of width and height is 0.
xyโ Specify the offsets to place the input image at within the padded area, with respect to the top/left border of the output image.
The x expression can reference the value set by the y expression, and vice versa.
The default value of x and y is 0.
If x or y evaluate to a negative number, they'll be changed so the input image is centered on the padded area. (Not me auto-centering your whole life ๐ซถ)
colorโ Specify the color of the padded area. For the syntax of this option, check the "Color" section in theffmpeg-utilsmanual.
The default value of color is black.
evalโ Specify when to evaluatewidth,height,xandyexpression. It accepts the following values:initโ Only evaluate expressions once during the filter initialization or when a command is processed.frameโ Evaluate expressions for each incoming frame.
Default value is init.
aspectโ Pad to aspect instead to a resolution.
The value for the width, height, x, and y options are expressions containing the following constants:
in_win_hโ The input video width and height.iwihโ These are the same asin_wandin_h.out_wout_hโ The output width and height (the size of the padded area), as specified by thewidthandheightexpressions.owohโ These are the same asout_wandout_h.xyโ Thexandyoffsets as specified by thexandyexpressions, orNANif not yet specified.aโ same asiw / ihsarโ input sample aspect ratiodarโ input display aspect ratio, it is the same as(iw / ih) * sarhsubvsubโ The horizontal and vertical chroma subsample values. For example for the pixel format"yuv422p"hsubis2andvsubis1.
Examples ๐
- Add paddings with the color
"violet"to the input video. The output video size is640x480, and the top-left corner of the input video is placed at column0, row40โ violet era, obsessed:
pad=640:480:0:40:violet
The example above is equivalent to the following command:
pad=width=640:height=480:x=0:y=40:color=violet
- Pad the input to get an output with dimensions increased by 3/2, and put the input video at the center of the padded area:
pad="3/2*iw:3/2*ih:(ow-iw)/2:(oh-ih)/2"
- Pad the input to get a squared output with size equal to the maximum value between the input width and height, and put the input video at the center of the padded area:
pad="max(iw\,ih):ow:(ow-iw)/2:(oh-ih)/2"
- Pad the input to get a final w/h ratio of 16:9:
pad="ih*16/9:ih:(ow-iw)/2:(oh-ih)/2"
- In case of anamorphic video, in order to set the output display aspect correctly, it is necessary to use
sarin the expression, according to the relation:
(ih * X / ih) * sar = output_dar
X = output_dar / sar
Thus the previous example needs to be modified to:
pad="ih*16/9/sar:ih:(ow-iw)/2:(oh-ih)/2"
- Double the output size and put the input video in the bottom-right corner of the output padded area:
pad="2*iw:2*ih:ow-iw:oh-ih"
๐จ palettegen
Generate one palette for a whole video stream. It's the color mood board for your entire video, and yes it's doing the absolute most. โจ
It accepts the following options:
max_colorsโ Set the maximum number of colors to quantize in the palette. Note: the palette will still contain256colors; the unused palette entries will beblack. (So the leftovers are just chilling in black, no drama.)reserve_transparentโ Create a palette of255colors maximum and reserve the last one for transparency. Reserving the transparency color is useful for GIF optimization. If not set, the maximum of colors in the palette will be256. You probably want to disable this option for a standalone image. Set by default.transparency_colorโ Set the color that will be used as background for transparency.stats_modeโ Set statistics mode. It accepts the following values:fullโ Compute full frame histograms.diffโ Compute histograms only for the part that differs from previous frame. This might be relevant to give more importance to the moving part of your input if the background is static.singleโ Compute new histogram for each frame.
Default value is full.
The filter also exports the frame metadata "lavfi.color_quant_ratio" ("nb_color_in / nb_color_out") which you can use to evaluate the degree of color quantization of the palette. This information is also visible at info logging level. ๐
Examples ๐
- Generate a representative palette of a given video using ffmpeg:
ffmpeg -i input.mkv -vf palettegen palette.png
๐ paletteuse
Use a palette to downsample an input video stream. Basically palettegen's other half โ the one that actually does the coloring-in. ๐
The filter takes two inputs: one video stream and a palette. The palette must be a 256 pixels image.
It accepts the following options:
ditherโ Select dithering mode. Available algorithms are:bayerโ Ordered 8x8 bayer dithering (deterministic)heckbertโ Dithering as defined by Paul Heckbert in 1982 (simple error diffusion). Note: this dithering is sometimes considered "wrong" and is included as a reference.floyd_steinbergโ Floyd and Steingberg dithering (error diffusion)sierra2โ Frankie Sierra dithering v2 (error diffusion)sierra2_4aโ Frankie Sierra dithering v2 "Lite" (error diffusion)sierra3โ Frankie Sierra dithering v3 (error diffusion)burkesโ Burkes dithering (error diffusion)atkinsonโ Atkinson dithering by Bill Atkinson at Apple Computer (error diffusion)noneโ Disable dithering.
Default is sierra2_4a.
bayer_scaleโ When bayer dithering is selected, this option defines the scale of the pattern (how much the crosshatch pattern is visible). A low value means more visible pattern for less banding, and higher value means less visible pattern at the cost of more banding.
The option must be an integer value in the range [0,5]. Default is 2.
diff_modeโ If set, define the zone to process.rectangleโ Only the changing rectangle will be reprocessed. This is similar to GIF cropping/offsetting compression mechanism. This option can be useful for speed if only a part of the image is changing, and has use cases such as limiting the scope of the error diffusal dither to the rectangle that bounds the moving scene (it leads to more deterministic output if the scene doesn't change much, and as a result less moving noise and better GIF compression).
Default is none.
newโ Take new palette for each output frame.alpha_thresholdโ Sets the alpha threshold for transparency. Alpha values above this threshold will be treated as completely opaque, and values below this threshold will be treated as completely transparent.
The option must be an integer value in the range [0,255]. Default is 128.
Examples ๐ฆ
- Use a palette (generated for example with
palettegen) to encode a GIF using ffmpeg:
ffmpeg -i input.mkv -i palette.png -lavfi paletteuse output.gif
๐ perspective
Correct perspective of video not recorded perpendicular to the screen. (Filmed it at a cursed angle? We fix. Un-cursed. ๐)
okay so here's exactly what it takes, bestie:
x0,y0,x1,y1,x2,y2,x3,y3โ set the coordinate expressions for the top left, top right, bottom left and bottom right corners. Default is"0:0:W:0:0:H:W:H", and with that the perspective just... stays the same, no drama. If thesenseoption is"source", then the points you gave get sent to the corners of the destination. Ifsenseis"destination", then the corners of the source get sent to the coordinates you specified. ๐ฆ
Your expressions can use these variables:
W,Hโ the width and height of the video frame.inโ input frame count.onโ output frame count.
interpolationโ set the interpolation used for the perspective correction. Accepted values:linearcubic
Default value is linear. ๐
senseโ set how the coordinate options are interpreted. Accepted values:0,sourceโ send the point in the source specified by the given coordinates to the corners of the destination.1,destinationโ send the corners of the source to the point in the destination specified by the given coordinates.
Default value is source. โจ
evalโ set when the expressions for the coordinatesx0,y0,...x3,y3get evaluated. Accepted values:initโ only evaluate expressions once during filter initialization, or when a command is processed.frameโ evaluate expressions for each incoming frame.
Default value is init.
๐ธ phase ๐ธ
This one delays interlaced video by one field time so the field order gets flipped. It's giving "fixer upper".
The intended use is fixing PAL movies that got captured with the opposite field order to the film-to-video transfer. ๐
A description of the accepted parameters follows:
modeโ set the phase mode. Accepted values:tโ capture field order top-first, transfer bottom-first. The filter will delay the bottom field.bโ capture field order bottom-first, transfer top-first. The filter will delay the top field.pโ capture and transfer with the same field order. This mode literally only exists so the other options have something to refer to in the docs โ but if you actually select it, the filter will faithfully do nothing. no cap, it's a professional no-op. ๐ญaโ capture field order determined automatically by field flags, transfer opposite. The filter picks betweentandbmodes on a frame-by-frame basis using field flags. If no field information is available, then this works just likeu.uโ capture unknown or varying, transfer opposite. The filter picks betweentandbon a frame-by-frame basis by analyzing the images and selecting the alternative that produces the best match between the fields.Tโ capture top-first, transfer unknown or varying. The filter picks betweentandpusing image analysis.Bโ capture bottom-first, transfer unknown or varying. The filter picks betweenbandpusing image analysis.Aโ capture determined by field flags, transfer unknown or varying. The filter picks betweent,bandpusing field flags and image analysis. If no field information is available, then this works just likeU. This is the default mode. ๐Uโ both capture and transfer unknown or varying. The filter picks betweent,bandpusing image analysis only.
Commands ๐ซถ
This filter supports the all above options as commands.
๐ง photosensitivity ๐ง
Reduces the various flashes in video, so it can help users with epilepsy. genuinely such a kind filter, we stan. ๐
It accepts the following options:
frames,fโ set how many frames to use when filtering. Default is30.threshold,tโ set the detection threshold factor. Default is1. Lower is stricter.skipโ set how many pixels to skip when sampling frames. Default is1. Allowed range is from1to1024.bypassโ leave frames unchanged. Default is disabled.
โญ pixdesctest โญ
Pixel format descriptor test filter, mainly useful for internal testing. The output video should be equal to the input video โ like, that's the whole vibe check.
For example:
format=monow, pixdesctest
can be used to test the monowhite pixel format descriptor definition.
๐ pixelize ๐
Apply pixelization to video stream. artsy. blocky. iconic.
The filter accepts the following options:
width,wandheight,hโ set the block dimensions that will be used for pixelization. Default value is16.mode,mโ set the mode of pixelization used. Possible values are:avgminmax
Default value is "avg".
planes,pโ set what planes to filter. Default is to filter all planes.
Commands ๐ซถ
This filter supports all options as commands.
๐ฆ pixscope ๐ฆ
Display sample values of the color channels. Mainly useful for checking color and levels. Minimum supported resolution is 640x480 โ so no tiny frames, she needs room to breathe.
The filters accept the following options:
xโ set scope X position, relative offset on X axis.yโ set scope Y position, relative offset on Y axis.wโ set scope width.hโ set scope height.oโ set window opacity. This window also holds statistics about the pixel area.wxโ set window X position, relative offset on X axis.wyโ set window Y position, relative offset on Y axis.
Commands ๐ซถ
This filter supports same commands as options.
๐ pp7 ๐
Apply Postprocessing filter 7. It's a variant of the spp filter, similar to spp = 6 with 7 point DCT, where only the center sample is used after IDCT.
The filter accepts the following options:
qpโ force a constant quantization parameter. It accepts an integer in range0to63. If not set, the filter will use the QP from the video stream (if available).modeโ set thresholding mode. Available modes are:hardโ set hard thresholding.softโ set soft thresholding (better de-ringing effect, but likely blurrier).mediumโ set medium thresholding (good results, default). ๐
๐
premultiply ๐
Apply alpha premultiply effect to the input video stream, using the first plane of the second stream as alpha.
Both streams must have the same dimensions and the same pixel format. no exceptions, bestie.
The filter accepts the following option:
planesโ set which planes will be processed, unprocessed planes will be copied. By default value0xf, all planes will be processed.inplaceโ do not require a 2nd input for processing, instead use the alpha plane from the input stream.
โจ premultiply_dynamic โจ
Dynamically premultiply or unpremultiply the input video stream as needed, to match the requirements of the downstream filter graph. This is roughly equivalent to either "premultiply:inplace=yes" or "unpremultiply:inplace=yes", or otherwise a noop. she's adaptable like that. ๐ง
The filter accepts the following option:
planesโ set which planes will be processed, unprocessed planes will be copied. By default value0xf, all planes will be processed.
๐ฅ prewitt ๐ฅ
Apply the prewitt operator to the input video stream. edge detection main character energy.
The filter accepts the following option:
planesโ set which planes will be processed, unprocessed planes will be copied. By default value0xf, all planes will be processed.scaleโ set the value which will be multiplied with the filtered result.deltaโ set the value which will be added to the filtered result.
Commands ๐ซถ
This filter supports the all above options as commands.
๐ pseudocolor ๐
Alter frame colors in video with pseudocolors. it's giving aesthetic overhaul, honestly.
This filter accepts the following options:
c0โ set pixel first component expression.c1โ set pixel second component expression.c2โ set pixel third component expression.c3โ set pixel fourth component expression, corresponds to the alpha component.index,iโ set component to use as base for altering colors.preset,pโ pick one of the built-in LUTs. By default is set tonone. Available LUTs:magmainfernoplasmaviridisturbocividisrange1range2shadowshighlightssolarnominalpreferredtotalspectralcoolheatfierybluesgreenhelix
opacityโ set opacity of output colors. Allowed range is from0to1. Default value is set to1.
Each of the expression options specifies the expression to use for computing the lookup table for the corresponding pixel component values. ๐จ
The expressions can contain the following constants and functions:
w,hโ the input width and height.valโ the input value for the pixel component.ymin,umin,vmin,aminโ the minimum allowed component value.ymax,umax,vmax,amaxโ the maximum allowed component value.
All expressions default to "val".
Commands ๐ซถ
This filter supports the all above options as commands.
Examples
- Change too high luma values to gradient:
pseudocolor="'if(between(val,ymax,amax),lerp(ymin,ymax,(val-ymax)/(amax-ymax)),-1):if(between(val,ymax,amax),lerp(umax,umin,(val-ymax)/(amax-ymax)),-1):if(between(val,ymax,amax),lerp(vmin,vmax,(val-ymax)/(amax-ymax)),-1):-1'"
๐ psnr ๐
Obtain the average, maximum and minimum PSNR (Peak Signal to Noise Ratio) between two input videos. quality-checking queen.
This filter takes in input two input videos โ the first input is considered the "main" source and is passed unchanged to the output. The second input is used as a "reference" video for computing the PSNR.
Both video inputs must have the same resolution and pixel format for this filter to work correctly. Also it assumes that both inputs have the same number of frames, which are compared one by one. ๐
The obtained average PSNR is printed through the logging system.
The filter stores the accumulated MSE (mean squared error) of each frame, and at the end of the processing it is averaged across all frames equally, and the following formula is applied to obtain the PSNR:
PSNR = 10*log10(MAX^2/MSE)
Where MAX is the average of the maximum values of each component of the image. ๐
The description of the accepted parameters follows.
stats_file,fโ if specified the filter will use the named file to save the PSNR of each individual frame. When filename equals"-"the data is sent to standard output.stats_versionโ specifies which version of the stats file format to use. Details of each format are written below. Default value is1.output_maxโ decides whether the max value gets output to the stats log. Default value is0. Requiresstats_version >= 2. If this is set andstats_version < 2, the filter will return an error.
bestie, this filter also supports the framesync options. ๐
The file printed if stats_file is selected contains a sequence of key/value pairs of the form key:value for each compared couple of frames.
If a stats_version greater than 1 is specified, a header line precedes the list of per-frame-pair stats, with key value pairs following the frame format with the following parameters:
psnr_log_versionโ the version of the log file format. Will matchstats_version.fieldsโ a comma separated list of the per-frame-pair parameters included in the log.
A description of each shown per-frame-pair parameter follows, bestie:
nโ sequential number of the input frame, starting from1.mse_avgโ Mean Square Error pixel-by-pixel average difference of the compared frames, averaged over all the image components.mse_y,mse_u,mse_v,mse_r,mse_g,mse_b,mse_aโ Mean Square Error pixel-by-pixel average difference of the compared frames for the component specified by the suffix.psnr_y,psnr_u,psnr_v,psnr_r,psnr_g,psnr_b,psnr_aโ Peak Signal to Noise ratio of the compared frames for the component specified by the suffix.max_avg,max_y,max_u,max_vโ Maximum allowed value for each channel, and average over all channels.
๐ Examples ๐
- For example:
movie=ref_movie.mpg, setpts=PTS-STARTPTS [main];
[main][ref] psnr="stats_file=stats.log" [out]
On this example the input file being processed is compared with the reference file ref_movie.mpg. The PSNR of each individual frame is stored in stats.log.
- Another example with different containers:
ffmpeg -i main.mpg -i ref.mkv -lavfi "[0:v]settb=AVTB,setpts=PTS-STARTPTS[main];[1:v]settb=AVTB,setpts=PTS-STARTPTS[ref];[main][ref]psnr" -f null -
๐ pullup ๐
Pulldown reversal (inverse telecine) filter, capable of handling mixed hard-telecine, 24000/1001 fps progressive, and 30000/1001 fps progressive content. Iconic, honestly.
The pullup filter is designed to take advantage of future context in making its decisions. This filter is stateless in the sense that it does not lock onto a pattern to follow, but it instead looks forward to the following fields in order to identify matches and rebuild progressive frames. future context queen โจ
To produce content with an even framerate, insert the fps filter after pullup, use fps=24000/1001 if the input frame rate is 29.97fps, fps=24 for 30fps and the (rare) telecined 25fps input.
This filter accepts the following options:
jl,jr,jt,jbโ These options set the amount of "junk" to ignore at the left, right, top, and bottom of the image, respectively. Left and right are in units of8pixels, while top and bottom are in units of2lines. The default is8pixels on each side.sbโ Set the strict breaks. Setting this option to1will reduce the chances of filter generating an occasional mismatched frame, but it may also cause an excessive number of frames to be dropped during high motion sequences. Conversely, setting it to-1will make filter match fields more easily. This may help processing of video where there is slight blurring between the fields, but may also cause there to be interlaced frames in the output. Default value is0.mpโ Set the metric plane to use. It accepts the following values:lโ Use luma plane.uโ Use chroma blue plane.vโ Use chroma red plane.
This option may be set to use chroma plane instead of the default luma plane for doing filter's computations. This may improve accuracy on very clean source material, but more likely will decrease accuracy, especially if there is chroma noise (rainbow effect) or any grayscale video. The main purpose of setting mp to a chroma plane is to reduce CPU load and make pullup usable in realtime on slow machines. realtime on slow machines, we love efficiency ๐ซถ
For best results (without duplicated frames in the output file) it is necessary to change the output frame rate. For example, to inverse telecine NTSC input:
ffmpeg -i input -vf pullup -r 24000/1001 ...
๐ฆ qp ๐ฆ
Change video quantization parameters (QP). short and powerful ๐
The filter accepts the following option:
qpโ Set expression for quantization parameter.
The expression is evaluated through the eval API and can contain, among others, the following constants:
knownโ1if index is not129,0otherwise.qpโ Sequential index starting from-129to128.
๐ Examples ๐
- Some equation like:
qp=2+2*sin(PI*qp)
๐ qrencode ๐
Generate a QR code using the libqrencode library (see https://fukuchi.org/works/qrencode/), and overlay it on top of the current frame. QR code era โจ
To enable the compilation of this filter, you need to configure FFmpeg with --enable-libqrencode.
The QR code is generated from the provided text or text pattern. The corresponding QR code is scaled and overlaid into the video output according to the specified options.
In case no text is specified, no QR code is overlaied. (yes, that spelling is in the original, love that for us) ๐
This filter accepts the following options:
qrcode_width,q,padded_qrcode_width,Qโ Specify an expression for the width of the rendered QR code, with and without padding. Theqrcode_widthexpression can reference the value set by thepadded_qrcode_widthexpression, and vice versa. By defaultpadded_qrcode_widthis set toqrcode_width, meaning that there is no padding.
These expressions are evaluated for each new frame.
See the qrencode Expressions section for details.
x,yโ Specify an expression for positioning the padded QR code top-left corner. Thexexpression can reference the value set by theyexpression, and vice versa.
By default x and y are set set to 0, meaning that the QR code is placed in the top left corner of the input. set set, iconic ๐
These expressions are evaluated for each new frame.
See the qrencode Expressions section for details.
case_sensitive,csโ Instruct libqrencode to use case sensitive encoding. This is enabled by default. This can be disabled to reduce the QR encoding size.level,lโ Specify the QR encoding error correction level. With a higher correction level, the encoding size will increase but the code will be more robust to corruption. Lower level isL.LMQH
expansionโ Select how the input text is expanded. Can be either"none", or"normal"(default). See the qrencode Text expansion section below for details.text,textfileโ Define the text to be rendered. In case neither is specified, no QR is encoded (just an empty colored frame).
In case expansion is enabled, the text is treated as a text template, using the qrencode expansion mechanism. See the qrencode Text expansion section below for details.
background_color,bc,foreground_color,fcโ Set the QR code and background color. The default value offoreground_coloris"black", the default value ofbackground_coloris"white".
For the syntax of the color options, check the "Color" section in the ffmpeg-utils manual.
๐ง qrencode Expressions ๐ง
The expressions set by the options contain the following constants and functions.
darโ input display aspect ratio, it is the same as(w / h) * sar.durationโ the current frame's duration, in seconds.hsub,vsubโ horizontal and vertical chroma subsample values. For example for the pixel format"yuv422p"hsubis2andvsubis1.main_h,Hโ the input height.main_w,Wโ the input width.nโ the number of input frame, starting from0.pict_typeโ a number representing the picture type.qr_w,wโ the width of the encoded QR code.rendered_qr_w,q,rendered_padded_qr_w,Qโ the width of the rendered QR code, without and without padding.- These parameters allow the
qandQexpressions to refer to each other, so you can for example specifyq=3/4*Q.
- These parameters allow the
rand(min, max)โ return a random number included betweenminandmax.sarโ the input sample aspect ratio.tโ timestamp expressed in seconds,NANif the input timestamp is unknown.x,yโ the x and y offset coordinates where the text is drawn.- These parameters allow the
xandyexpressions to refer to each other, so you can for example specifyy=x/dar.
- These parameters allow the
๐ธ qrencode Text expansion ๐ธ
If expansion is set to "none", the text is printed verbatim.
If expansion is set to "normal" (which is the default), the following expansion mechanism is used.
The backslash character \, followed by any character, always expands to the second character.
Sequences of the form %{...} are expanded. The text between the braces is a function name, possibly followed by arguments separated by ':'. If the arguments contain special characters or delimiters (':' or '}'), they should be escaped.
Note that they probably must also be escaped as the value for the text option in the filter argument string and as the filter argument in the filtergraph description, and possibly also for the shell, that makes up to four levels of escaping; using a text file with the textfile option avoids these problems.
The following functions are available:
n,frame_numโ return the frame number.ptsโ Return the presentation timestamp of the current frame.
It can take up to two arguments.
The first argument is the format of the timestamp; it defaults to "flt" for seconds as a decimal number with microsecond accuracy; "hms" stands for a formatted [-]HH:MM:SS.mmm timestamp with millisecond accuracy. "gmtime" stands for the timestamp of the frame formatted as UTC time; "localtime" stands for the timestamp of the frame formatted as local time zone time. If the format is set to "hms24hh", the time is formatted in 24h format (00-23).
The second argument is an offset added to the timestamp.
If the format is set to "localtime" or "gmtime", a third argument may be supplied: a strftime C function format string. By default, YYYY-MM-DD HH:MM:SS format will be used.
expr,eโ Evaluate the expression's value and output as a double.
It must take one argument specifying the expression to be evaluated, accepting the constants and functions defined in qrencode_expressions.
expr_formatted,efโ evaluates an expression and spits it back out as a formatted string ๐ the first argument is the expression (same deal as theexprfunction), the second is the output format, and the allowed values arex,X,danduโ all treated exactly like in the"printf"function. Third parameter is optional and sets how many positions the output takes up, so you can pad with zeros on the left ๐gmtimeโ the time the filter is running, expressed in UTC โฐ it can take an argument: a"strftime"C function format string. That format string is extended to support the variable%[1-6]N, which prints fractions of the second with an optionally specified number of digits โจlocaltimeโ same energy asgmtimebut in the local time zone ๐ takes an argument too, a"strftime"C function format string, extended to support%[1-6]Nfor fractions of the second with optionally specified digits ๐ฐ๏ธmetadataโ frame metadata, and it takes one or two arguments ๐ท๏ธ The first argument is mandatory and is the metadata key. The second is optional and is the default value used when that metadata key isn't found or is empty. Wanna know what metadata you actually have? Go inspect the entries starting withTAGinside each frame section printed by running"ffprobe -show_frames"๐ String metadata generated in filters that lead into theqrencodefilter is available too ๐rand(min, max)โ returns a random number between min and max ๐ฒ
โจ Examples โจ
- Generate a QR code encoding the specified text with the default size, overlaid in the top left corner of the input video, with the default size:
qrencode=text=www.ffmpeg.org
- Same as below, but select blue on pink colors:
qrencode=text=www.ffmpeg.org:bc=pink@0.5:fc=blue
- Place the QR code in the bottom right corner of the input video:
qrencode=text=www.ffmpeg.org:x=W-Q:y=H-Q
- Generate a QR code with width of 200 pixels and padding, making the padded width 4/3 of the QR code width:
qrencode=text=www.ffmpeg.org:q=200:Q=4/3*q
- Generate a QR code with padded width of 200 pixels and padding, making the QR code width 3/4 of the padded width:
qrencode=text=www.ffmpeg.org:Q=200:q=3/4*Q
- Make the QR code a fraction of the input video width:
qrencode=text=www.ffmpeg.org:q=W/5
- Generate a QR code encoding the frame number:
qrencode=text=%{n}
- Generate a QR code encoding the GMT timestamp:
qrencode=text=%{gmtime}
- Generate a QR code encoding the timestamp expressed as a float:
qrencode=text=%{pts}
๐ quirc ๐
Identifies and decodes a QR code using the libquirc library (check it out at <https://github.com/dlbeer/quirc/>), and prints the identified QR codes' positions and payload as metadata ๐
To even compile this filter, you have to configure FFmpeg with "--enable-libquirc" โ no flag, no quirc, that's the whole vibe ๐ง
For every QR code found in the input video, some metadata entries get added with the prefix lavfi.quirc.N, where N is the index starting from 0 that's associated with that QR code ๐ฆ
Description of each metadata value, coming right up:
lavfi.quirc.countโ the number of QR codes found, and it is not set if none were found ๐lavfi.quirc.N.corner.M.xlavfi.quirc.N.coreer.M.yโ the x/y positions of the four corners of the square containing the QR code, whereMis the index of the corner starting from0๐ (yes,coreeris literally how it's spelled in the page โ i'm not touching it, don't come for me ๐)lavfi.quirc.N.payloadโ the payload of the QR code ๐ฆ
๐ฒ random ๐ฒ
Flushes video frames from the internal frame cache into a random order. Not a single frame gets discarded, bestie โ nothing is lost ๐ซถ Inspired by the frei0r nervous filter.
framesโ sets the size in number of frames of the internal cache, in range from2to512. Default is30.seedโ sets the seed for the random number generator, and it must be an integer between0and"UINT32_MAX". If it's not specified, or if it's explicitly set to less than0, the filter will try to use a good random seed on a best effort basis โจ
๐บ readeia608 ๐บ
Reads closed captioning (EIA-608) info from the top lines of a video frame ๐ผ
This filter adds frame metadata for "lavfi.readeia608.X.cc" and "lavfi.readeia608.X.line", where "X" is the number of the identified line with EIA-608 data (starting from 0). Each metadata value explained:
lavfi.readeia608.X.ccโ the two bytes stored as EIA-608 data (printed in hexadecimal) ๐ขlavfi.readeia608.X.lineโ the number of the line on which the EIA-608 data was identified and read ๐
This filter accepts the following options:
scan_minโ set the line to start scanning for EIA-608 data. Default is0.scan_maxโ set the line to end scanning for EIA-608 data. Default is29.spwโ set the ratio of width reserved for sync code detection. Default is0.27. Allowed range is"[0.1 - 0.7]"๐chpโ enable checking the parity bit. If there's a parity error, the filter outputs0x00for that character instead. Default isfalse๐lpโ lowpass lines prior to further processing. Default is enabled โ
๐ Commands ๐
This filter supports all of the above options as commands ๐
๐ฅ Examples ๐ฅ
- Output a csv with presentation time and the first two lines of identified EIA-608 captioning data:
ffprobe -f lavfi -i movie=captioned_video.mov,readeia608 -show_entries frame=pts_time:frame_tags=lavfi.readeia608.0.cc,lavfi.readeia608.1.cc -of csv
โฑ๏ธ readvitc โฑ๏ธ
Reads vertical interval timecode (VITC) info from the top lines of a video frame ๐ฌ
The filter adds the frame metadata key "lavfi.readvitc.tc_str" holding the timecode value โ but only if a valid timecode has actually been detected. There's also another metadata key, "lavfi.readvitc.found", set to 0/1 depending on whether timecode data was found or not ๐
This filter accepts the following options:
scan_maxโ set the maximum number of lines to scan for VITC data. If the value is set to-1, the full video frame gets scanned. Default is45.thr_bโ set the luma threshold for black. Accepts float numbers in the range[0.0,1.0], default value is0.2. The value must be equal to or less than"thr_w"โ ๏ธthr_wโ set the luma threshold for white. Accepts float numbers in the range[0.0,1.0], default value is0.6. The value must be equal to or greater than"thr_b"โ ๏ธ
๐ธ Examples ๐ธ
- Detect and draw VITC data onto the video frame; if no valid VITC is detected, draw
"--:--:--:--"as a placeholder:
ffmpeg -i input.avi -filter:v 'readvitc,drawtext=fontfile=FreeMono.ttf:text=%{metadata\\:lavfi.readvitc.tc_str\\:--\\\\\\:--\\\\\\:--\\\\\\:--}:x=(w-tw)/2:y=400-ascent'
๐บ๏ธ remap ๐บ๏ธ
Remaps pixels using the 2nd input video stream as Xmap and the 3rd as Ymap ๐
The destination pixel at position (X, Y) gets picked from the source position (x, y), where x = Xmap(X, Y) and y = Ymap(X, Y). If the mapping values land out of range, a zero value for the pixel is used for that destination pixel ๐ณ๏ธ
The Xmap and Ymap input video streams must be the same dimensions. The output video stream will have Xmap/Ymap video stream dimensions. Xmap and Ymap input video streams are 16bit depth, single channel ๐
formatโ specify the pixel format of the output from this filter. Can be"color"or"gray". Default is"color".fillโ specify the color of the unmapped pixels. For the syntax of this option, check the"Color"section in the ffmpeg-utils manual. Default color is"black"๐ค
๐งผ removegrain ๐งผ
The removegrain filter is a spatial denoiser for progressive video โจ
m0โ set mode for the first plane.m1โ set mode for the second plane.m2โ set mode for the third plane.m3โ set mode for the fourth plane.
Range of mode is from 0 to 24. Here's what each mode does, buckle up bestie:
0โ leave input plane unchanged. Default.1โ clips the pixel with the minimum and maximum of the 8 neighbour pixels.2โ clips the pixel with the second minimum and maximum of the 8 neighbour pixels.3โ clips the pixel with the third minimum and maximum of the 8 neighbour pixels.4โ clips the pixel with the fourth minimum and maximum of the 8 neighbour pixels. This is equivalent to a median filter.5โ line-sensitive clipping giving the minimal change.6โ line-sensitive clipping, intermediate.7โ line-sensitive clipping, intermediate.8โ line-sensitive clipping, intermediate.9โ line-sensitive clipping on a line where the neighbour pixels are the closest.10โ replaces the target pixel with the closest neighbour.11โ[1 2 1]horizontal and vertical kernel blur.12โ same as mode11.13โ bob mode, interpolates top field from the line where the neighbour pixels are the closest.14โ bob mode, interpolates bottom field from the line where the neighbour pixels are the closest.15โ bob mode, interpolates top field. Same as13but with a more complicated interpolation formula.16โ bob mode, interpolates bottom field. Same as14but with a more complicated interpolation formula.17โ clips the pixel with the minimum and maximum of respectively the maximum and minimum of each pair of opposite neighbour pixels.18โ line-sensitive clipping using opposite neighbours whose greatest distance from the current pixel is minimal.19โ replaces the pixel with the average of its 8 neighbours.20โ averages the 9 pixels ([1 1 1]horizontal and vertical blur).21โ clips pixels using the averages of opposite neighbour.22โ same as mode21but simpler and faster.23โ small edge and halo removal, but reputed useless ๐24โ similar as23.
๐ญ removelogo ๐ญ
Suppresses a TV station logo, using an image file to figure out which pixels make up the logo ๐ท๏ธ It works by filling in the pixels that comprise the logo with neighboring pixels ๐ซถ
The filter accepts the following options:
filename,fโ set the filter bitmap file, which can be any image format supported by libavformat. The width and height of the image file must match those of the video stream being processed โ ๏ธ
Pixels in the provided bitmap image with a value of zero are not considered part of the logo โ non-zero pixels are considered part of the logo. If you use white (255) for the logo and black (0) for the rest, you will be safe ๐
For making the filter bitmap, it's recommended to take a screen capture of a black frame with the logo visible, and then use a threshold filter followed by the erode filter once or twice ๐ธ
If you need to, you can also patch little splotches by hand. But bestie, listen: if any logo pixels end up not covered, the filter quality drops hard. Marking too many pixels as part of the logo doesn't hurt as much, but it means more blurring is needed to cover the image up, which destroys more information than necessary โ and all those extra pixels will slow things down on a large logo. So likeโฆ be reasonable ๐
repeatfields
This one peeks at the repeat_field flag in the Video ES headers and hard-repeats fields based on whatever value it finds. Respect the header's authority, basically ๐
reverse
Reverses a video clip. That's it, that's the whole vibe. โช
โ ๏ธ Warning: this filter needs enough memory to buffer the entire clip, so trimming first is strongly suggested. Do not just yeet a two-hour video at it, babe.
Examples
- Take the first 5 seconds of a clip and reverse it:
trim=end=5,reverse
rgbashift
Shifts the R/G/B/A pixels horizontally and/or vertically. Little nudge left, little nudge up, whatever you're feeling ๐ซ
The filter takes these options:
rhโ how much to shift red horizontally.rvโ how much to shift red vertically.ghโ how much to shift green horizontally.gvโ how much to shift green vertically.bhโ how much to shift blue horizontally.bvโ how much to shift blue vertically.ahโ how much to shift alpha horizontally.avโ how much to shift alpha vertically.edgeโ set the edge mode. Can besmear,default, orwarp.
Commands
This filter supports all the above options as commands. Every single one, slay ๐ซถ
roberts
Applies the roberts cross operator to the input video stream. Edge detection era โจ
The filter takes this option:
planesโ sets which planes get processed; unprocessed planes just get copied along. Default value is0xf, which means all planes are processed.scaleโ sets a value that gets multiplied with the filtered result.deltaโ sets a value that gets added to the filtered result.
Commands
This filter supports all the above options as commands too ๐
rotate
Rotates the video by an arbitrary angle, expressed in radians. Fancy, angular, main character energy ๐
The filter takes these options:
Here's the description of the optional parameters, mwah:
angle,aโ sets an expression for the angle by which to rotate the input video clockwise, expressed as a number of radians. A negative value gives you a counter-clockwise rotation. Default is"0".
This expression is evaluated for each frame.
out_w,owโ sets the output width expression. Default value is"iw". This expression is evaluated just once, during configuration.out_h,ohโ sets the output height expression. Default value is"ih". This expression is evaluated just once, during configuration.bilinearโ turns bilinear interpolation on if set to1, and a value of0disables it. Default value is1.fillcolor,cโ sets the color used to fill the output area that the rotated image doesn't cover. For the general syntax of this option, go check the Color section in theffmpeg-utilsmanual. If you pick the special value"none", then no background gets printed at all (super useful when the background is never shown, iykyk).
Default value is "black".
The expressions for the angle and the output size can contain these constants and functions:
nโ sequential number of the input frame, starting from0. It is alwaysNANbefore the first frame is filtered.tโ time in seconds of the input frame; it's set to0when the filter is configured. It is alwaysNANbefore the first frame is filtered.hsub,vsubโ horizontal and vertical chroma subsample values. For example, for the pixel formatyuv422p,hsubis2andvsubis1.in_w,iwandin_h,ihโ the input video width and height.out_w,owandout_h,ohโ the output width and height, that is, the size of the padded area as specified by the width and height expressions.rotw(a),roth(a)โ the minimal width/height required to completely contain the input video rotated byaradians.
These are only available when computing the out_w and out_h expressions. Periodt.
Examples
- Rotate the input by PI/6 radians clockwise:
rotate=PI/6
- Rotate the input by PI/6 radians counter-clockwise:
rotate=-PI/6
- Rotate the input by 45 degrees clockwise:
rotate=45*PI/180
- Apply a constant rotation with period
T, starting from an angle of PI/3:
rotate=PI/3+2*PI*t/T
- Make the input video rotation oscillate with a period of
Tseconds and an amplitude ofAradians:
rotate=A*sin(2*PI/T*t)
- Rotate the video, with the output size chosen so that the whole rotating input video is always completely contained in the output:
rotate='2*PI*t:ow=hypot(iw,ih):oh=ow'
- Rotate the video, and reduce the output size so that no background is ever shown:
rotate=2*PI*t:ow='min(iw,ih)/sqrt(2)':oh=ow:c=none
Commands
The filter supports these commands:
a,angleโ sets the angle expression. The command accepts the same syntax as the corresponding option.
If the expression you give it isn't valid, it just stays at its current value. No drama ๐
sab
Applies Shape Adaptive Blur. Soft and smart about it ๐ธ
The filter takes these options:
luma_radius,lrโ sets the luma blur filter strength. Must be a value in the range0.1-4.0, default value is1.0. A greater value gives you a more blurred image, and slower processing.luma_pre_filter_radius,lpfrโ sets the luma pre-filter radius. Must be a value in the0.1-2.0range, default value is1.0.luma_strength,lsโ sets the luma maximum difference between pixels to still be considered. Must be a value in the0.1-100.0range, default value is1.0.chroma_radius,crโ sets the chroma blur filter strength. Must be a value in the range-0.9-4.0. A greater value gives you a more blurred image, and slower processing.chroma_pre_filter_radius,cpfrโ sets the chroma pre-filter radius. Must be a value in the-0.9-2.0range.chroma_strength,csโ sets the chroma maximum difference between pixels to still be considered. Must be a value in the-0.9-100.0range.
Every chroma option value, if you don't explicitly specify it, gets set to the corresponding luma option value. Copying its bestie's homework fr fr ๐
scale
Scales (resizes) the input video, using the libswscale library. The classic glow-up filter ๐
The scale filter forces the output display aspect ratio to be the same as the input's, by changing the output sample aspect ratio.
If the input image format is different from the format requested by the next filter, the scale filter converts the input to the requested format. Helpful king.
Options
The filter accepts the following options, plus any of the options supported by the libswscale scaler, plus any of the framesync options.
๐ See the ffmpeg-scaler manual for the complete list of scaler options. Go read it, bestie, it's giving reference material.
width,wandheight,hโ set the output video dimension expression. Default value is the input dimension.
If the width or w value is 0, the input width is used for the output. If the height or h value is 0, the input height is used for the output.
If one and only one of the values is -n with n >= 1, the scale filter uses a value that maintains the aspect ratio of the input image, calculated from the other specified dimension. After that, however, it makes sure the calculated dimension is divisible by n and adjusts the value if necessary.
If both values are -n with n >= 1, the behavior is identical to both values being set to 0 as detailed above.
See below for the list of accepted constants to use in the dimension expression.
evalโ specifies when to evaluate the width and height expressions. It accepts these values:initโ only evaluate expressions once during filter initialization, or when a command is processed.frameโ evaluate expressions for each incoming frame.
Default value is init.
interlโ sets the interlacing mode. It accepts these values:1โ force interlaced aware scaling.0โ do not apply interlaced scaling.-1โ select interlaced aware scaling depending on whether the source frames are flagged as interlaced or not.
Default value is 0.
flagsโ sets thelibswscalescaling flags. See theffmpeg-scalermanual for the complete list of values. If not explicitly specified, the filter applies the default flags.param0,param1โ setslibswscaleinput parameters for scaling algorithms that need them. See theffmpeg-scalermanual for the complete documentation. If not explicitly specified, the filter applies empty parameters.intentโ sets the ICC rendering intent to use when transforming between different color spaces. It accepts these values:perceptualโ use a perceptually guided tone and gamut mapping curve. The exact details of the mapping used may change at any time and should not be relied on as stable. This intent is recommended for final viewing of image/video content in typical viewing settings.relative_colorimetricโ statically clip out-of-gamut colors using a colorimetric clipping curve which attempts to find the colorimetrically least dissimilar in-gamut color. This intent performs white point adaptation and black point adaptation. This is the default. This intent is recommended wherever faithful color reproduction is of the utmost importance, even at the cost of clipping.absolute_colorimetricโ hard clip out-of-gamut colors with no attempt at white or black point reproduction. This intent reproduces in-gamut colors1:1on the output display as they would appear on the reference display, assuming the output display is appropriately calibrated.saturationโ performs saturation mapping โ that is, it stretches the input color volume directly onto the output color volume, in a non-linear fashion that preserves the original signal appearance as much as possible. This intent is recommended for signal content evaluation, since it will not lead to any clipping. It's roughly analogous to not performing any color mapping, although it still takes into account the mastering display primaries and any differences in encoding TRC.
size,sโ sets the video size. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual.in_color_matrix,out_color_matrixโ set the in/output YCbCr color space type.
This lets you override whatever got autodetected, and it also lets you force a specific value that gets used for the output and the encoder. If you don't specify it, the color space type just depends on the pixel format. ๐
Possible values:
autoโ choose automatically.bt709โ format conforming to International Telecommunication Union (ITU) Recommendation BT.709.fccโ set color space conforming to the United States Federal Communications Commission (FCC) Code of Federal Regulations (CFR) Title 47 (2003) 73.682 (a).bt601,bt470,smpte170mโ set color space conforming to:- ITU Radiocommunication Sector (ITU-R) Recommendation BT.601
- ITU-R Rec. BT.470-6 (1998) Systems B, B1, and G
- Society of Motion Picture and Television Engineers (SMPTE) ST 170:2004
smpte240mโ set color space conforming to SMPTE ST 240:1999.bt2020โ set color space conforming to ITU-R BT.2020 non-constant luminance system.
in_range, out_range โ set the in/output YCbCr sample range. ๐๏ธ
Same deal: override the autodetected value, or force a specific one for the output and encoder. If you don't specify it, the range depends on the pixel format. Possible values:
auto/unknownโ choose automatically.jpeg/full/pcโ set full range (0-255in case of 8-bit luma).mpeg/limited/tvโ set "MPEG" range (16-235in case of 8-bit luma).
in_chroma_loc, out_chroma_loc โ set the in/output chroma sample location. If you don't specify it, center-sited chroma is used by default. Possible values: ๐ฏ
auto,unknownleftcentertoplefttopbottomleftbottom
in_primaries, out_primaries โ set the in/output RGB primaries. ๐
Override the autodetected value, or force a specific one for the output and encoder, bestie. Possible values:
autoโ choose automatically. This is the default.bt709bt470mbt470bgsmpte170msmpte240mfilmbt2020smpte428smpte431smpte432jedec-p22ebu3213
in_transfer, out_transfer โ set the in/output transfer response curve (TRC). ๐
Override the autodetected value, or force a specific one for the output and encoder. Possible values:
autoโ choose automatically. This is the default.bt709bt470mgamma22bt470bggamma28smpte170msmpte240mlineariec61966-2-1srgbiec61966-2-4xvyccbt1361ebt2020-10bt2020-12smpte2084smpte428arib-std-b67
force_original_aspect_ratio โ lets the output video width or height decrease or increase when it needs to, so the original aspect ratio stays intact. ๐ซถ Possible values:
disableโ scale the video exactly as specified and turn this feature off.decreaseโ the output video dimensions get automatically decreased if needed.increaseโ the output video dimensions get automatically increased if needed.
One genuinely iconic use case: when you know a specific device's maximum allowed resolution, you can use this to cap the output video at that, while keeping the aspect ratio. Say device A allows 1280x720 playback and your video is 1920x800. Use this option (set it to decrease) and pass 1280x720 on the command line, and the output becomes 1280x533. โจ
Heads up, this is a different thing than specifying-1forworhโ you still need to specify the output resolution for this option to actually work. No cap, fr.
force_divisible_by โ makes sure both output dimensions, width and height, are divisible by the integer you give it, when used together with force_original_aspect_ratio. Works similar to using -n in the w and h options. ๐ข
This option respects whatever value you set for force_original_aspect_ratio, bumping the resolution up or down accordingly. The video's aspect ratio may be slightly modified โ just so you know.
It's lowkey handy if you need a video to fit within (or exceed) a defined resolution via force_original_aspect_ratio, but your encoder has opinions about width or height divisibility.
reset_sar โ enabling this leads to the output SAR being reset to 1. On top of that, if the user asks for proportional scaling through the width or height expressions โ like w=-4:h=360 or w=iw/2:h=-1 โ or by enabling force_original_aspect_ratio, then the input DAR gets taken into account and the output is scaled to produce square pixels. Default is false. ๐ฆ
The values of the w and h options are expressions, and they can contain these constants:
in_w, in_h โ the input width and height.
iw, ih โ these are the same as in_w and in_h.
out_w, out_h โ the output (scaled) width and height.
ow, oh โ these are the same as out_w and out_h.
a โ the same as iw / ih.
sar โ input sample aspect ratio.
dar โ the input display aspect ratio. Calculated from (iw / ih) * sar.
hsub, vsub โ horizontal and vertical input chroma subsample values. For example, for the pixel format yuv422p, hsub is 2 and vsub is 1.
ohsub, ovsub โ horizontal and vertical output chroma subsample values. For example, for the pixel format yuv422p, hsub is 2 and vsub is 1.
n โ the (sequential) number of the input frame, starting from 0. Only available with eval=frame.
t โ the presentation timestamp of the input frame, expressed as a number of seconds. Only available with eval=frame.
pos โ the position (byte offset) of the frame in the input stream, or NaN if this info is unavailable and/or meaningless (like, in the case of synthetic video). Only available with eval=frame. Deprecated, do not use. ๐
ref_w, rw, ref_h, rh, ref_a, ref_dar, rdar, ref_n, ref_t, ref_pos โ equivalent to the above, but for a second reference input. If any of these variables are present, this filter accepts two inputs. ๐
Examples ๐
- Scale the input video to a size of
200x100:
scale=w=200:h=100
This is equivalent to:
scale=200:100
or:
scale=200x100
- Specify a size abbreviation for the output size:
scale=qcif
which can also be written as:
scale=size=qcif
- Scale the input to 2x:
scale=w=2*iw:h=2*ih
- The above is the same as:
scale=2*in_w:2*in_h
- Scale the input to 2x with forced interlaced scaling:
scale=2*iw:2*ih:interl=1
- Scale the input to half size:
scale=w=iw/2:h=ih/2
- Increase the width, and set the height to the same size:
scale=3/2*iw:ow
- Seek Greek harmony ๐๏ธ:
scale=iw:1/PHI*iw
scale=ih*PHI:ih
- Increase the height, and set the width to 3/2 of the height:
scale=w=3/2*oh:h=3/5*ih
- Increase the size, making the size a multiple of the chroma subsample values:
scale="trunc(3/2*iw/hsub)*hsub:trunc(3/2*ih/vsub)*vsub"
- Increase the width to a maximum of 500 pixels, keeping the same aspect ratio as the input:
scale=w='min(500\, iw*3/2):h=-1'
- Make pixels square by combining
scaleandsetsar:
scale='trunc(ih*dar):ih',setsar=1/1
- Make pixels square using
reset_sar, making sure the resulting resolution is even (required by some codecs):
scale='-2:ih-mod(ih,2):reset_sar=1'
- Scale to target exactly, however reset SAR to
1:
scale='400:300:reset_sar=1'
- Scale to even dimensions that fit within
400x300, preserving input SAR:
scale='400:300:force_original_aspect_ratio=decrease:force_divisible_by=2'
- Scale to produce square pixels with even dimensions that fit within
400x300:
scale='400:300:force_original_aspect_ratio=decrease:force_divisible_by=2:reset_sar=1'
- Scale a subtitle stream (
sub) to match the main video (main) in size before overlaying. (scale2ref) ๐
'[main]split[a][b]; [ref][a]scale=rw:rh[c]; [b][c]overlay'
- Scale a logo to 1/10th the height of a video, while preserving its display aspect ratio:
[logo-in][video-in]scale=w=oh*dar:h=rh/10[logo-out]
Commands
This filter supports the following commands:
width, w, height, h โ set the output video dimension expression. The command accepts the same syntax as the corresponding option.
If the specified expression is not valid, it's kept at its current value. No drama. ๐
scharr
Apply the scharr operator to the input video stream. ๐
The filter accepts the following option:
planesโ set which planes will be processed; unprocessed planes get copied. By default the value is0xf, so all planes are processed.scaleโ set the value that gets multiplied with the filtered result.deltaโ set the value that gets added to the filtered result.
Commands
This filter supports all the above options as commands. ๐
scroll
Scroll the input video horizontally and/or vertically at a constant speed. ๐๏ธ
The filter accepts the following options:
horizontal,hโ set the horizontal scrolling speed. Default is0. Allowed range is from-1to1. Negative values change the scrolling direction.vertical,vโ set the vertical scrolling speed. Default is0. Allowed range is from-1to1. Negative values change the scrolling direction.hposโ set the initial horizontal scrolling position. Default is0. Allowed range is from0to1.vposโ set the initial vertical scrolling position. Default is0. Allowed range is from0to1.
Commands
This filter supports the following commands:
horizontal,hโ set the horizontal scrolling speed.vertical,vโ set the vertical scrolling speed.
scdet
Detect video scene changes. ๐
This filter sets frame metadata with mafd between frame, the scene score, and forwards the frame on to the next filter, so they can use that metadata to detect scene changes or whatever else they're into. โจ
In addition, this filter logs a message and sets frame metadata when it detects a scene change by threshold.
lavfi.scd.mafdโ metadata key set withmafdfor every single frame, no cap ๐ซถlavfi.scd.scoreโ metadata key set with the scene change score for every frame, so you can actually detect a scene changelavfi.scd.timeโ metadata key set with the current filtered frame time that detected a scene change with the threshold
The filter accepts the following options:
threshold,tโ sets the scene change detection threshold as a percentage of maximum change. Good values live in the[8.0, 14.0]range, and the range forthresholditself is[0., 100.]. Default value is10..sc_pass,sโ sets the flag to pass scene change frames to the next filter. Default value is0. Enable it if you literally only want a snapshot of the scene change frames ๐
๐ selectivecolor ๐
Adjust cyan, magenta, yellow and black (CMYK) to certain ranges of colors (like reds, yellows, greens, cyans, โฆ). The adjustment range is defined by the purity of the color โ meaning how saturated it already is. Iconic.
This filter is similar to the Adobe Photoshop Selective Color tool. Photoshop girlies, this one's for you โจ
The filter accepts the following options:
correction_methodโ selects the color correction method. Available values are:absoluteโ specified adjustments are applied "as-is" (added/subtracted to the original pixel component value).relativeโ specified adjustments are relative to the original component value.
Default is absolute.
redsโ adjustments for red pixels (pixels where the red component is the maximum)yellowsโ adjustments for yellow pixels (pixels where the blue component is the minimum)greensโ adjustments for green pixels (pixels where the green component is the maximum)cyansโ adjustments for cyan pixels (pixels where the red component is the minimum)bluesโ adjustments for blue pixels (pixels where the blue component is the maximum)magentasโ adjustments for magenta pixels (pixels where the green component is the minimum)whitesโ adjustments for white pixels (pixels where all components are greater than128)neutralsโ adjustments for all pixels except pure black and pure whiteblacksโ adjustments for black pixels (pixels where all components are lesser than128)psfileโ specify a Photoshop selective color file (.asv) to import the settings from. Bestie, you can straight-up import your presets, we're so back ๐ฆ
All the adjustment settings (reds, yellows, โฆ) accept up to 4 space separated floating point adjustment values in the [-1,1] range, respectively to adjust the amount of cyan, magenta, yellow and black for the pixels of its range.
Examples โจ
- Increase cyan by 50% and reduce yellow by 33% in every green areas, and increase magenta by 27% in blue areas:
selectivecolor=greens=.5 0 -.33 0:blues=0 .27
- Use a Photoshop selective color preset:
selectivecolor=psfile=MySelectiveColorPresets/Misty.asv
๐ธ separatefields ๐ธ
The separatefields filter takes a frame-based video input and splits each frame into its components fields, producing a new half height clip with twice the frame rate and twice the frame count. Half the height, double the drama, periodt.
This filter uses field-dominance information in the frame to decide which of each pair of fields to place first in the output. If it gets it wrong, use the setfield filter before the separatefields filter. Trust. ๐
๐ setdar, setsar ๐
The setdar filter sets the Display Aspect Ratio for the filter output video.
This is done by changing the specified Sample (aka Pixel) Aspect Ratio, according to the following equation:
<DAR> = <HORIZONTAL_RESOLUTION> / <VERTICAL_RESOLUTION> * <SAR>
Keep in mind that the setdar filter does not modify the pixel dimensions of the video frame. Also, the display aspect ratio set by this filter may be changed by later filters in the filterchain โ like if something scales, or if another setdar or a setsar filter gets applied. So don't come for me if a later filter undoes your work ๐ญ
The setsar filter sets the Sample (aka Pixel) Aspect Ratio for the filter output video.
Note that as a consequence of the application of this filter, the output display aspect ratio will change according to the equation above.
Keep in mind that the sample aspect ratio set by the setsar filter may be changed by later filters in the filterchain, e.g. if another setsar or a setdar filter is applied. Same vibe, same warning ๐
It accepts the following parameters:
r,ratio,dar(setdaronly),sar(setsaronly) โ set the aspect ratio used by the filter. The parameter can be a floating point number string, or an expression. If the parameter is not specified, the value0is assumed, meaning that the same input value is used.maxโ set the maximum integer value to use for expressing numerator and denominator when reducing the expressed aspect ratio to a rational. Default value is100.
The parameter sar is an expression containing the following constants:
w,hโ the input width and height.aโ same asw / h.sarโ the input sample aspect ratio.darโ the input display aspect ratio. It is the same as(w / h) * sar.hsub,vsubโ horizontal and vertical chroma subsample values. For example, for the pixel formatyuv422p,hsubis2andvsubis1.
Examples ๐
- To change the display aspect ratio to 16:9, specify one of the following:
setdar=dar=1.77777
setdar=dar=16/9
- To change the sample aspect ratio to 10:11, specify:
setsar=sar=10/11
- To set a display aspect ratio of 16:9, and specify a maximum integer value of 1000 in the aspect ratio reduction, use the command:
setdar=ratio=16/9:max=1000
๐ฆ setfield ๐ฆ
Force field for the output video frame. Main character energy for your interlacing.
The setfield filter marks the interlace type field for the output frames. It does not change the input frame, but only sets the corresponding property โ which affects how the frame is treated by following filters (e.g. fieldorder or yadif). It's giving "just setting the vibe, not touching the pixels."
The filter accepts the following options:
modeโ available values are:autoโ keep the same field property.bffโ mark the frame as bottom-field-first.tffโ mark the frame as top-field-first.progโ mark the frame as progressive.
โญ setparams โญ
Force frame parameter for the output video frame.
The setparams filter marks interlace and color range for the output frames. It does not change the input frame, but only sets the corresponding property, which affects how the frame is treated by filters/encoders. Same deal as before: no pixel touching, just labels ๐ท๏ธ
field_modeโ available values are:autoโ keep the same field property (default).bffโ mark the frame as bottom-field-first.tffโ mark the frame as top-field-first.progโ mark the frame as progressive.
rangeโ available values are:autoโ keep the same color range property (default).unspecified,unknownโ mark the frame as unspecified color range.limited,tv,mpegโ mark the frame as limited range.full,pc,jpegโ mark the frame as full range.
color_primariesโ set the color primaries. Available values are:autoโ keep the same color primaries property (default).bt709unknownbt470mbt470bgsmpte170msmpte240mfilmbt2020smpte428smpte431smpte432jedec-p22
color_trcโ set the color transfer. Available values are:autoโ keep the same color trc property (default).bt709unknownbt470mbt470bgsmpte170msmpte240mlinearlog100log316iec61966-2-4bt1361eiec61966-2-1bt2020-10bt2020-12smpte2084smpte428arib-std-b67
colorspaceโ set the colorspace. Available values are:autoโ keep the same colorspace property (default).gbrbt709unknownfccbt470bgsmpte170msmpte240mycgcobt2020ncbt2020csmpte2085chroma-derived-ncchroma-derived-cictcp
chroma_locationโ set the chroma sample location. Available values are:autoโ keep the same chroma location (default).unspecified,unknownleftcentertoplefttopbottomleftbottom
alpha_modeโ set the alpha moda. (Yes, the manpage really says "moda" and honestly? We're keeping her ๐๐ ) Available values are:autoโ keep the same alpha mode (default).unspecified,unknownpremultipliedstraight
๐ฅ shear ๐ฅ
Apply shear transform to input video. Slanting your whole video, why not.
This filter supports the following options:
shxโ shear factor in X-direction. Default value is0. Allowed range is from-2to2.shyโ shear factor in Y-direction. Default value is0. Allowed range is from-2to2.fillcolor,cโ set the color used to fill the output area not covered by the transformed video. For the general syntax of this option, check the "Color" section in theffmpeg-utilsmanual. If the special valuenoneis selected then no background is printed (useful for example if the background is never shown). Default value isblack.interpโ set interpolation type. Can bebilinearornearest. Default isbilinear.
Commands
This filter supports the all above options as commands. Yup, all of them, live, at runtime, go off ๐
๐ showinfo ๐
Show a line containing various information for each input video frame. The input video is not modified โ she's just reading, not touching, we love a respectful icon.
This filter supports the following options:
checksumโ calculate checksums of each plane. By default enabled.udu_sei_as_asciiโ try to print user data unregistered SEI as ascii character when possible, in hex format otherwise.
The shown line contains a sequence of key/value pairs of the form key:value.
The following values are shown in the output:
nโ the (sequential) number of the input frame, starting from0.ptsโ the Presentation TimeStamp of the input frame, expressed as a number of time base units. The time base unit depends on the filter input pad.pts_timeโ the Presentation TimeStamp of the input frame, expressed as a number of seconds.fmtโ the pixel format name.sarโ the sample aspect ratio of the input frame, expressed in the formnum/den.sโ the size of the input frame, periodt. For the actual syntax of this option, go peek at the "Video size" section in theffmpeg-utilsmanual, bestie, it's all there ๐iโ the type of interlaced mode:"P"for "progressive","T"for top field first,"B"for bottom field first. Three letters, three vibes โจiskeyโ this is1if the frame is a key frame,0otherwise. Main character frame or background extra, no in between ๐typeโ the picture type of the input frame:"I"for an I-frame,"P"for a P-frame,"B"for a B-frame, or"?"for an unknown type. Also lowkey go refer to the documentation of the"AVPictureType"enum and of the"av_get_picture_type_char"function defined inlibavutil/avutil.h, if you wanna go deeper ๐ฆchecksumโ the Adler-32 checksum (printed in hexadecimal) of all the planes of the input frame. Whole-frame fingerprint energy ๐ฅplane_checksumโ the Adler-32 checksum (printed in hexadecimal) of each plane of the input frame, expressed in the form"[c0 c1 c2 c3]"๐ซถmeanโ the mean value of pixels in each plane of the input frame, expressed in the form"[mean0 mean1 mean2 mean3]"๐ธstdevโ the standard deviation of pixel values in each plane of the input frame, expressed in the form"[stdev0 stdev1 stdev2 stdev3]"โญ
๐ showpalette ๐
Displays the 256 colors palette of each frame. Heads up: this filter is only relevant for pal8 pixel format frames โ like, it will simply not serve for other formats, ngl ๐
It accepts the following option:
sโ set the size of the box used to represent one palette color entry. Default is30(for a"30x30"pixel box). Cute little squares, one per color ๐จ
๐ฆ shuffleframes ๐ฆ
Reorder and/or duplicate and/or drop video frames. Chaos, but make it intentional ๐
It accepts the following parameter:
mappingโ set the destination indexes of input frames. This is a space or'|'separated list of indexes that maps input frames to output frames. The number of indexes also sets the maximal value that each index may have. The'-1'index has special meaning and that is to drop the frame ๐
The first frame has the index 0. The default is to keep the input unchanged.
โจ Examples โจ
- Swap second and third frame of every three frames of the input:
ffmpeg -i INPUT -vf "shuffleframes=0 2 1" OUTPUT
- Swap 10th and 1st frame of every ten frames of the input:
ffmpeg -i INPUT -vf "shuffleframes=9 1 2 3 4 5 6 7 8 0" OUTPUT
๐ shufflepixels ๐
Reorder pixels in video frames. Yes, pixels. Yes, it's unhinged. Yes, we love it ๐ฅ
This filter accepts the following options:
direction,dโ set shuffle direction. Can be forward or inverse direction. Default direction is forward.mode,mโ set shuffle mode. Can behorizontal,verticalorblockmode.width,wandheight,hโ set shuffleblock_size. In case of horizontal shuffle mode only the width part of the size is used, and in case of vertical shuffle mode only the height part of the size is used. iykyk ๐ซถseed,sโ set random seed used with shuffling pixels. Mainly useful to set so you're able to reverse the filtering process and get the original input back. For example, to reverse forward shuffle you need to use the same parameters and the exact same seed, and to set direction to inverse. Screenshot the seed, bestie, or it's gone forever ๐ญ
๐ shuffleplanes ๐
Reorder and/or duplicate video planes. Plane remix, no cap ๐
It accepts the following parameters:
map0โ the index of the input plane to be used as the first output plane.map1โ the index of the input plane to be used as the second output plane.map2โ the index of the input plane to be used as the third output plane.map3โ the index of the input plane to be used as the fourth output plane.
The first plane has the index 0. The default is to keep the input unchanged.
โจ Examples โจ
- Swap the second and third planes of the input:
ffmpeg -i INPUT -vf shuffleplanes=0:2:1:3 OUTPUT
๐ signalstats ๐
Evaluate various visual metrics that assist in determining issues associated with the digitization of analog video media. Think of it as a vibe check for your analog captures ๐
By default the filter will log these metadata values:
YMINโ display the minimal Y value contained within the input frame. Expressed in range of[0-255].YLOWโ display the Y value at the 10% percentile within the input frame. Expressed in range of[0-255].YAVGโ display the average Y value within the input frame. Expressed in range of[0-255].YHIGHโ display the Y value at the 90% percentile within the input frame. Expressed in range of[0-255].YMAXโ display the maximum Y value contained within the input frame. Expressed in range of[0-255].UMINโ display the minimal U value contained within the input frame. Expressed in range of[0-255].ULOWโ display the U value at the 10% percentile within the input frame. Expressed in range of[0-255].UAVGโ display the average U value within the input frame. Expressed in range of[0-255].UHIGHโ display the U value at the 90% percentile within the input frame. Expressed in range of[0-255].UMAXโ display the maximum U value contained within the input frame. Expressed in range of[0-255].VMINโ display the minimal V value contained within the input frame. Expressed in range of[0-255].VLOWโ display the V value at the 10% percentile within the input frame. Expressed in range of[0-255].VAVGโ display the average V value within the input frame. Expressed in range of[0-255].VHIGHโ display the V value at the 90% percentile within the input frame. Expressed in range of[0-255].VMAXโ display the maximum V value contained within the input frame. Expressed in range of[0-255].SATMINโ display the minimal saturation value contained within the input frame. Expressed in range of[0-~181.02].SATLOWโ display the saturation value at the 10% percentile within the input frame. Expressed in range of[0-~181.02].SATAVGโ display the average saturation value within the input frame. Expressed in range of[0-~181.02].SATHIGHโ display the saturation value at the 90% percentile within the input frame. Expressed in range of[0-~181.02].SATMAXโ display the maximum saturation value contained within the input frame. Expressed in range of[0-~181.02].HUEMEDโ display the median value for hue within the input frame. Expressed in range of[0-360].HUEAVGโ display the average value for hue within the input frame. Expressed in range of[0-360].YDIFโ display the average of sample value difference between all values of the Y plane in the current frame and corresponding values of the previous input frame. Expressed in range of[0-255].UDIFโ display the average of sample value difference between all values of the U plane in the current frame and corresponding values of the previous input frame. Expressed in range of[0-255].VDIFโ display the average of sample value difference between all values of the V plane in the current frame and corresponding values of the previous input frame. Expressed in range of[0-255].YBITDEPTHโ display bit depth of Y plane in current frame. Expressed in range of[0-16].UBITDEPTHโ display bit depth of U plane in current frame. Expressed in range of[0-16].VBITDEPTHโ display bit depth of V plane in current frame. Expressed in range of[0-16].
The filter accepts the following options:
stat,outโstatspecifies an additional form of image analysis.outoutputs video with the specified type of pixel highlighted.
Both options accept the following values:
toutโ identify temporal outliers pixels. A temporal outlier is a pixel unlike the neighboring pixels of the same field. Examples of temporal outliers include the results of video dropouts, head clogs, or tape tracking issues.vrepโ identify vertical line repetition. Vertical line repetition includes similar rows of pixels within a frame. In born-digital video, vertical line repetition is common, but this pattern is uncommon in video digitized from an analog source. When it occurs in video that results from the digitization of an analog source it can indicate concealment from a dropout compensator.brngโ identify pixels that fall outside of legal broadcast range.
color,cโ set the highlight color for theoutoption. The default color isyellow๐
โจ Examples โจ
- Output data of various video metrics:
ffprobe -f lavfi movie=example.mov,signalstats="stat=tout+vrep+brng" -show_frames
- Output specific data about the minimum and maximum values of the Y plane per frame:
ffprobe -f lavfi movie=example.mov,signalstats -show_entries frame_tags=lavfi.signalstats.YMAX,lavfi.signalstats.YMIN
- Playback video while highlighting pixels that are outside of broadcast range in red:
ffplay example.mov -vf signalstats="out=brng:color=red"
- Playback video with signalstats metadata drawn over the frame:
ffplay example.mov -vf signalstats=stat=brng+vrep+tout,drawtext=fontfile=FreeSerif.ttf:textfile=signalstat_drawtext.txt
The contents of signalstat_drawtext.txt used in the command are:
time %{pts:hms}
Y (%{metadata:lavfi.signalstats.YMIN}-%{metadata:lavfi.signalstats.YMAX})
U (%{metadata:lavfi.signalstats.UMIN}-%{metadata:lavfi.signalstats.UMAX})
V (%{metadata:lavfi.signalstats.VMIN}-%{metadata:lavfi.signalstats.VMAX})
saturation maximum: %{metadata:lavfi.signalstats.SATMAX}
๐ signature ๐
Calculates the MPEG-7 Video Signature. Bestie, this filter can handle more than one input โ and when it does, the matching between the inputs can be calculated additionally. The filter always passes through the first input. The signature of each stream can be written into a file ๐
It accepts the following options:
detectmodeโ enable or disable the matching process.
Available values are:
offโ disable the calculation of a matching (default).fullโ calculate the matching for the whole video and output whether the whole video matches or only parts.fastโ calculate only until a matching is found or the video ends. Should be faster in some cases.
nb_inputsโ set the number of inputs. The option value must be a non negative integer. Default value is1.filenameโ sets the path where the output gets written. โจ Heads up though: if you've got more than one input, this path has to be a prototype, meaning it must contain%dor%0nd(where n is a positive integer) โ that bit gets swapped out for the input number. And if you don't specify a filename at all? No output gets written, periodt. That's literally the default. ๐formatโ picks the output format. Your options are:binaryโ use the specified binary representation (this is the default, bestie).xmlโ use the specified xml representation.
th_dโ sets the threshold for detecting one word as similar. Value's gotta be an integer greater than zero. Default is9000.th_dcโ sets the threshold for detecting all words as similar. Integer greater than zero, please. Default is60000.th_xhโ sets the threshold for detecting frames as similar. Integer greater than zero. Default is116.th_diโ sets the minimum length of a sequence, in frames, to actually recognize it as a matching sequence. Gotta be a non-negative integer. Default is0.th_itโ sets the minimum relation that matching frames to all frames must have. Gotta be a double between0and1. Default is0.5.
๐ธ Examples ๐ธ
- To calculate the signature of an input video and store it in
signature.bin:
ffmpeg -i input.mkv -vf signature=filename=signature.bin -map 0:v -f null -
- To detect whether two videos match and store the signatures in XML format in
signature0.xmlandsignature1.xml:
ffmpeg -i input1.mkv -i input2.mkv -filter_complex "[0:v][1:v] signature=nb_inputs=2:detectmode=full:format=xml:filename=signature%d.xml" -map :v -f null -
siti ๐
Calculates Spatial Information (SI) and Temporal Information (TI) scores for a video, as defined in ITU-T Rec. P.910 (11/21): Subjective video quality assessment methods for multimedia applications. The PDF lives at <https://www.itu.int/rec/T-REC-P.910-202111-S/en>. โญ
Okay so real talk: this is a legacy implementation that corresponds to a superseded recommendation. If you want the latest version, refer to ITU-T Rec. P.910 (07/22): <https://www.itu.int/rec/T-REC-P.910-202207-I/en> ๐
It accepts this one option:
print_summaryโ if set to1, Summary statistics get printed to the console. Default is0.
๐ฆ Examples ๐ฆ
- To calculate SI/TI metrics and print summary:
ffmpeg -i input.mp4 -vf siti=print_summary=1 -f null -
smartblur โจ
Blurs the input video without messing with the outlines. Iconic behaviour honestly. ๐ซถ
It accepts these options:
luma_radius,lrโ sets the luma radius. Gotta be a float in the range[0.1,5.0]that specifies the variance of the gaussian filter used to blur the image (slower if larger). Default is1.0.luma_strength,lsโ sets the luma strength. Float in the range[-1.0,1.0]that configures the blurring. A value in[0.0,1.0]blurs the image, whereas a value in[-1.0,0.0]sharpens it. Default is1.0.luma_threshold,ltโ sets the luma threshold, used as a coefficient to decide whether a pixel should be blurred or not. Integer in the range[-30,30]. A value of0filters the whole image, a value in[0,30]filters flat areas, and a value in[-30,0]filters edges. Default is0.chroma_radius,crโ sets the chroma radius. Float in the range[0.1,5.0]specifying the variance of the gaussian filter used to blur (slower if larger). Default isluma_radius.chroma_strength,csโ sets the chroma strength. Float in the range[-1.0,1.0]configuring the blurring.[0.0,1.0]blurs,[-1.0,0.0]sharpens. Default isluma_strength.chroma_threshold,ctโ sets the chroma threshold, the coefficient for deciding whether a pixel gets blurred. Integer in the range[-30,30].0filters the whole image,[0,30]filters flat areas,[-30,0]filters edges. Default isluma_threshold.alpha_radius,arโ sets the alpha radius. Float in the range[0.1,5.0]specifying the variance of the gaussian filter used to blur (slower if larger). Default isluma_radius.alpha_strength,asโ sets the alpha strength. Float in the range[-1.0,1.0]configuring the blurring.[0.0,1.0]blurs,[-1.0,0.0]sharpens. Default isluma_strength.alpha_threshold,atโ sets the alpha threshold, the coefficient for deciding whether a pixel gets blurred. Integer in the range[-30,30].0filters the whole image,[0,30]filters flat areas,[-30,0]filters edges. Default isluma_threshold.
And here's the little rule that ties it all together, bestie: if a chroma or alpha option isn't explicitly set, the corresponding luma value gets used instead. ๐ง
sobel ๐ฅ
Applies the sobel operator to the input video stream. Edges? Detected. Slay.
The filter accepts these options:
planesโ sets which planes get processed; the unprocessed ones are copied as-is. Default value is0xf, meaning all planes get processed.scaleโ sets the value that gets multiplied with the filtered result.deltaโ sets the value that gets added to the filtered result.
๐ Commands ๐
This filter supports all the above options as commands. iykyk.
spp ๐
Applies a simple postprocessing filter that compresses and decompresses the image at several shifts (or โ when the quality level is 6 โ all of them) and averages the results.
The filter accepts these options:
qualityโ sets the quality. This option defines the number of levels for averaging. It takes an integer in the range0-6. If set to0, the filter has no effect, zero, nada. A value of6means the higher quality. And bestie, for each increment of that value, the speed drops by a factor of approximately2. Default is3.qpโ forces a constant quantization parameter. If it's not set, the filter uses the QP from the video stream (if available).modeโ sets the thresholding mode. Available modes:hardโ sets hard thresholding (default).softโ sets soft thresholding (better de-ringing effect, but likely blurrier).
use_bframe_qpโ enables the use of the QP from the B-Frames if set to1.
Ngl, using this option may cause flicker, since the B-Frames often have a larger QP. Default is 0 (not enabled). ๐
๐ Commands ๐
This filter supports these commands:
quality,levelโ sets the quality level. The value"max"can be used to set the maximum level, currently6.
sr ๐
Scales the input by applying one of the super-resolution methods based on convolutional neural networks. Supported models:
- Super-Resolution Convolutional Neural Network model (SRCNN). See <https://arxiv.org/abs/1501.00092>.
- Efficient Sub-Pixel Convolutional Neural Network model (ESPCN). See <https://arxiv.org/abs/1609.05158>.
Training scripts as well as scripts for model file (.pb) saving can be found at <https://github.com/XueweiMeng/sr/tree/sr_dnn_native>. Original repository is at <https://github.com/HighVoltageRocknRoll/sr.git>. โญ
The filter accepts these options:
dnn_backendโ specifies which DNN backend to use for model loading and execution. Accepts these values:tensorflowโ TensorFlow backend. To enable it you need to install the TensorFlow for C library (see <https://www.tensorflow.org/install/lang_c>) and configure FFmpeg with"--enable-libtensorflow".
modelโ sets the path to the model file specifying network architecture and its parameters. Note that different backends use different file formats. TensorFlow and OpenVINO backend can load files for only its format.scale_factorโ sets the scale factor for the SRCNN model. Allowed values are2,3and4. Default is2. This factor is necessary for the SRCNN model, because it accepts input upscaled using bicubic upscaling with proper scale factor.
If you want the full functionality (like async execution), please use the dnn_processing filter instead. ๐
sr_amf ๐ธ
Upscales (size increasing) the input video using the AMD Advanced Media Framework library for hardware acceleration. Uses advanced algorithms for upscaling with higher output quality. Setting the output width and height works the same way as for the scale filter. โจ
The filter accepts these options:
w,hโ set the output video dimension expression. Default value is the input dimension. Allows for the same expressions as thescalefilter.algorithmโ sets the algorithm used for scaling:bilinearโ Bilinearbicubicโ Bicubicsr1-0โ Video SR1.0. This is a default valuepointโ Pointsr1-1โ Video SR1.1
sharpnessโ controls hq scaler sharpening. The value is a float in the range of[0.0, 2.0].formatโ controls the output pixel format. By default, or if none is specified, the input pixel format is used.keep-ratioโ forces the scaler to keep the aspect ratio of the input image when the output size has a different aspect ratio. Default value isfalse.fillโ specifies whether the output image outside the region of interest, which does not fill the entire output surface, should be filled with a solid color.
๐ Examples ๐
- Scale input to 720p, keeping aspect ratio and ensuring the output is
yuv420p:
sr_amf=-2:720:format=yuv420p
- Upscale to 4K with algorithm video SR1.1:
sr_amf=4096:2160:algorithm=sr1-1
ssim ๐
Obtains the SSIM (Structural SImilarity Metric) between two input videos. ๐
This filter takes in input two input videos: the first input is considered the "main" source and is passed unchanged to the output. The second input is used as a "reference" video for computing the SSIM.
okay so real talk bestie: both video inputs must have the same resolution and pixel format for this filter to work correctly. It also assumes both inputs have the same number of frames, and those frames get compared one by one. ๐ซถ
The filter stores the calculated SSIM of each frame.
The description of the accepted parameters follows.
stats_file,fโ if specified, the filter will use the named file to save the SSIM of each individual frame. When filename equals-, the data is sent to standard output.
The file printed if stats_file is selected contains a sequence of key/value pairs of the form key:value for each compared couple of frames.
A description of each shown parameter follows:
nโ sequential number of the input frame, starting from1.Y,U,V,R,G,Bโ SSIM of the compared frames for the component specified by the suffix.Allโ SSIM of the compared frames for the whole frame.dBโ same as above but in dB representation.
This filter also supports the framesync options.
โจ Examples
- For example:
movie=ref_movie.mpg, setpts=PTS-STARTPTS [main];
[main][ref] ssim="stats_file=stats.log" [out]
On this example the input file being processed is compared with the reference file ref_movie.mpg. The SSIM of each individual frame is stored in stats.log.
- Another example with both psnr and ssim at same time:
ffmpeg -i main.mpg -i ref.mpg -lavfi "ssim;[0:v][1:v]psnr" -f null -
- Another example with different containers:
ffmpeg -i main.mpg -i ref.mkv -lavfi "[0:v]settb=AVTB,setpts=PTS-STARTPTS[main];[1:v]settb=AVTB,setpts=PTS-STARTPTS[ref];[main][ref]ssim" -f null -
๐ซ stereo3d
Convert between different stereoscopic image formats.
The filters accept the following options:
inโ set stereoscopic image format of input.
Available values for input image formats are:
sbslโ side by side parallel (left eye left, right eye right)sbsrโ side by side crosseye (right eye left, left eye right)sbs2lโ side by side parallel with half width resolution (left eye left, right eye right)sbs2rโ side by side crosseye with half width resolution (right eye left, left eye right)abl,tblโ above-below (left eye above, right eye below)abr,tbrโ above-below (right eye above, left eye below)ab2l,tb2lโ above-below with half height resolution (left eye above, right eye below)ab2r,tb2rโ above-below with half height resolution (right eye above, left eye below)alโ alternating frames (left eye first, right eye second)arโ alternating frames (right eye first, left eye second)irlโ interleaved rows (left eye has top row, right eye starts on next row)irrโ interleaved rows (right eye has top row, left eye starts on next row)iclโ interleaved columns, left eye firsticrโ interleaved columns, right eye first
Default value is sbsl.
outโ set stereoscopic image format of output.sbslโ side by side parallel (left eye left, right eye right)sbsrโ side by side crosseye (right eye left, left eye right)sbs2lโ side by side parallel with half width resolution (left eye left, right eye right)sbs2rโ side by side crosseye with half width resolution (right eye left, left eye right)abl,tblโ above-below (left eye above, right eye below)abr,tbrโ above-below (right eye above, left eye below)ab2l,tb2lโ above-below with half height resolution (left eye above, right eye below)ab2r,tb2rโ above-below with half height resolution (right eye above, left eye below)alโ alternating frames (left eye first, right eye second)arโ alternating frames (right eye first, left eye second)irlโ interleaved rows (left eye has top row, right eye starts on next row)irrโ interleaved rows (right eye has top row, left eye starts on next row)arbgโ anaglyph red/blue gray (red filter on left eye, blue filter on right eye)arggโ anaglyph red/green gray (red filter on left eye, green filter on right eye)arcgโ anaglyph red/cyan gray (red filter on left eye, cyan filter on right eye)archโ anaglyph red/cyan half colored (red filter on left eye, cyan filter on right eye)arccโ anaglyph red/cyan color (red filter on left eye, cyan filter on right eye)arcdโ anaglyph red/cyan color optimized with the least squares projection of dubois (red filter on left eye, cyan filter on right eye)agmgโ anaglyph green/magenta gray (green filter on left eye, magenta filter on right eye)agmhโ anaglyph green/magenta half colored (green filter on left eye, magenta filter on right eye)agmcโ anaglyph green/magenta colored (green filter on left eye, magenta filter on right eye)agmdโ anaglyph green/magenta color optimized with the least squares projection of dubois (green filter on left eye, magenta filter on right eye)aybgโ anaglyph yellow/blue gray (yellow filter on left eye, blue filter on right eye)aybhโ anaglyph yellow/blue half colored (yellow filter on left eye, blue filter on right eye)aybcโ anaglyph yellow/blue colored (yellow filter on left eye, blue filter on right eye)aybdโ anaglyph yellow/blue color optimized with the least squares projection of dubois (yellow filter on left eye, blue filter on right eye)mlโ mono output (left eye only)mrโ mono output (right eye only)chlโ checkerboard, left eye firstchrโ checkerboard, right eye firsticlโ interleaved columns, left eye firsticrโ interleaved columns, right eye firsthdmiโ HDMI frame pack
Default value is arcd.
๐ Examples
- Convert input video from side by side parallel to anaglyph yellow/blue dubois:
stereo3d=sbsl:aybd
- Convert input video from above below (left eye above, right eye below) to side by side crosseye.
stereo3d=abl:sbsr
๐๏ธ streamselect, astreamselect
Select video or audio streams.
The filter accepts the following options:
inputsโ set number of inputs. Default is2.mapโ set input indexes to remap to outputs.
โจ๏ธ Commands
The streamselect and astreamselect filter supports the following commands:
mapโ set input indexes to remap to outputs.
โจ Examples
- Select first 5 seconds 1st stream and rest of time 2nd stream:
sendcmd='5.0 streamselect map 1',streamselect=inputs=2:map=0
- Same as above, but for audio:
asendcmd='5.0 astreamselect map 1',astreamselect=inputs=2:map=0
๐ฌ subtitles
Draw subtitles on top of input video using the libass library.
To enable compilation of this filter you need to configure FFmpeg with --enable-libass. This filter also requires a build with libavcodec and libavformat to convert the passed subtitles file to ASS (Advanced Substation Alpha) subtitles format.
The filter accepts the following options:
filename,fโ set the filename of the subtitle file to read. It must be specified.original_sizeโ specify the size of the original video, the video for which the ASS file was composed. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Due to a misdesign in ASS aspect ratio arithmetic, this is necessary to correctly scale the fonts if the aspect ratio has been changed.fontsdirโ set a directory path containing fonts that can be used by the filter. These fonts will be used in addition to whatever the font provider uses.alphaโ process alpha channel, by default alpha channel is untouched.charencโ set subtitles input character encoding.subtitlesfilter only. Only useful if not UTF-8.stream_index,siโ set subtitles stream index.subtitlesfilter only.force_styleโ override default style or script info parameters of the subtitles. It accepts a string containing ASS style formatKEY=VALUEcouples separated by,.wrap_unicodeโ break lines according to the Unicode Line Breaking Algorithm. Availability requires at least libass release0.17.0(orLIBASS_VERSION 0x01600010), and libass must have been built with libunibreak.
The option is enabled by default except for native ASS.
If the first key is not specified, it is assumed that the first value specifies the filename.
For example, to render the file sub.srt on top of the input video, use the command:
subtitles=sub.srt
which is equivalent to:
subtitles=filename=sub.srt
To render the default subtitles stream from file video.mkv, use:
subtitles=video.mkv
To render the second subtitles stream from that file, use:
subtitles=video.mkv:si=1
To make the subtitles stream from sub.srt appear in 80% transparent blue "DejaVu Serif", use:
subtitles=sub.srt:force_style='Fontname=DejaVu Serif,PrimaryColour=&HCCFF0000'
๐ง super2xsai
Scale the input by 2x and smooth using the Super2xSaI (Scale and Interpolate) pixel art scaling algorithm.
Useful for enlarging pixel art images without reducing sharpness. obsessed ๐
๐ swaprect
Swap two rectangular objects in video.
This filter accepts the following options:
wโ set object width.hโ set object height.x1โ set 1st rect x coordinate.y1โ set 1st rect y coordinate.x2โ set 2nd rect x coordinate.y2โ set 2nd rect y coordinate.
All expressions are evaluated once for each frame.
The all options are expressions containing the following constants:
w,hโ the input width and height.aโ same asw / h.sarโ input sample aspect ratio.darโ input display aspect ratio, it is the same as(w / h) * sar.nโ the number of the input frame, starting from0.tโ the timestamp expressed in seconds. It'sNANif the input timestamp is unknown.posโ the position in the file of the input frame,NANif unknown; deprecated, do not use.
โจ๏ธ Commands
This filter supports the all above options as commands.
swapuv
Swaps the U and V planes. That's it. That's the whole filter. ๐
tblend
Blends successive video frames together. ๐
See blend for the deets โ iykyk.
telecine
Applies the telecine process to your video. โจ
This filter accepts the following options:
first_fieldโ which field goes first:top,tโ top field first ๐ฅbottom,bโ bottom field first. The default value is"top".
patternโ a string of numbers representing the pulldown pattern you wanna apply. The default value is23.
Some typical patterns, since you're gonna ask:
NTSC output (30i):
27.5p: 32222
24p: 23 (classic)
24p: 2332 (preferred)
20p: 33
18p: 334
16p: 3444
PAL output (25i):
27.5p: 12222
24p: 222222222223 ("Euro pulldown")
16.67p: 33
16p: 33333334
thistogram
Computes and draws a color distribution histogram for the input video across time. โณ๐
Unlike the histogram video filter, which only shows the histogram of a single input frame at a certain time, this filter also shows past histograms, for however many frames the width option says.
The computed histogram is a representation of the color component distribution in an image. Fr fr.
The filter accepts the following options:
width,wโ sets the width of a single color component output. Default value is0. A value of0means the width will be picked from the input video. This also sets the number of passed histograms to keep. Allowed range is[0, 8192]. ๐display_mode,dโ sets the display mode. It accepts the following values:stackโ per color component graphs are placed below each other.paradeโ per color component graphs are placed side by side.overlayโ presents information identical to that in the"parade"mode, except that the graphs representing color components are superimposed directly over one another.
Default is "stack".
levels_mode,mโ sets the mode. Can be either"linear"or"logarithmic". Default is"linear".components,cโ sets which color components to display. Default is7.bgopacity,bโ sets the background opacity. Default is0.9.envelope,eโ show envelope. Default is disabled.ecolor,ecโ sets the envelope color. Default is"gold". ๐slideโ sets the slide mode:
Available values for slide are:
frameโ draw a new frame when the right border is reached.replaceโ replace old columns with new ones.scrollโ scroll from right to left.rscrollโ scroll from left to right.pictureโ draw a single picture.
Default is "replace".
threshold
Applies a threshold effect to the video stream. ๐ฒ
This filter needs four video streams to do its thresholding thing. The first stream is the stream we're filtering. The second stream holds threshold values, the third stream holds min values, and the last, fourth stream holds max values.
The filter accepts the following option:
planesโ sets which planes will be processed; unprocessed planes will be copied. By default the value is0xf, meaning all planes get processed.
So like, for example: if the first stream's pixel component value is less than the threshold value of that pixel component from the 2nd (threshold) stream, then the third stream's value gets picked โ otherwise the fourth stream's pixel component value gets picked.
Using the color source filter, one can perform various types of thresholding:
Commands
This filter supports all options as commands. ๐ฌ
Examples
- Binary threshold, using gray color as threshold:
ffmpeg -i 320x240.avi -f lavfi -i color=gray -f lavfi -i color=black -f lavfi -i color=white -lavfi threshold output.avi
- Inverted binary threshold, using gray color as threshold:
ffmpeg -i 320x240.avi -f lavfi -i color=gray -f lavfi -i color=white -f lavfi -i color=black -lavfi threshold output.avi
- Truncate binary threshold, using gray color as threshold:
ffmpeg -i 320x240.avi -f lavfi -i color=gray -i 320x240.avi -f lavfi -i color=gray -lavfi threshold output.avi
- Threshold to zero, using gray color as threshold:
ffmpeg -i 320x240.avi -f lavfi -i color=gray -f lavfi -i color=white -i 320x240.avi -lavfi threshold output.avi
- Inverted threshold to zero, using gray color as threshold:
ffmpeg -i 320x240.avi -f lavfi -i color=gray -i 320x240.avi -f lavfi -i color=white -lavfi threshold output.avi
thumbnail
Picks the most representative frame out of a given sequence of consecutive frames. ๐ผ๏ธโจ Main character detection, basically.
The filter accepts the following options:
nโ sets the frames batch size to analyze; in a set ofnframes, the filter will pick one of them, and then handle the next batch ofnframes until the end. Default is100.logโ sets the log level to display picked frame stats. Default is"info".
Since the filter keeps track of the whole frames sequence, a bigger n value will result in higher memory usage, so a high value is not recommended. ๐ญ Be nice to your RAM.
Examples
- Extract one picture each 50 frames:
thumbnail=50
- Complete example of a thumbnail creation with
ffmpeg:
ffmpeg -i in.avi -vf thumbnail,scale=300:200 -frames:v 1 out.png
tile
Tiles several successive frames together. ๐งฉ
The untile filter can do the reverse, bestie.
The filter accepts the following options:
layoutโ sets the grid size in the formCOLUMNSxROWS. Range goes up toUINT_MAXcells. Default is"6x5".nb_framesโ sets the maximum number of frames to render in the given area. It must be less than or equal towxh. The default value is0, meaning all the area will be used.marginโ sets the outer border margin in pixels. Range is0to1024. Default is0.paddingโ sets the inner border thickness (i.e. the number of pixels between frames). For more advanced padding options (like having different values for the edges), refer to thepadvideo filter. Range is0to1024. Default is0.colorโ specifies the color of the unused area. For the syntax of this option, check the"Color"section in theffmpeg-utilsmanual. The default value ofcoloris"black".overlapโ sets the number of frames to overlap when tiling several successive frames together. The value must be between0andnb_frames - 1. Default is0.init_paddingโ sets the number of frames to initially be empty before displaying the first output frame. This controls how soon you'll get your first output frame. The value must be between0andnb_frames - 1. Default is0.
Examples
- Produce 8x8 PNG tiles of all keyframes (
-skip_frame nokey) in a movie:
ffmpeg -skip_frame nokey -i file.avi -vf 'scale=128:72,tile=8x8' -an -vsync 0 keyframes%03d.png
The-vsync 0is necessary to preventffmpegfrom duplicating each output frame to accommodate the originally detected frame rate. Don't skip it, seriously. ๐
- Display 5 pictures in an area of
3x2frames, with 7 pixels between them, and 2 pixels of initial margin, using mixed flat and named options:
tile=3x2:nb_frames=5:padding=7:margin=2
tiltandshift
Applies a tilt-and-shift effect. ๐๐
So likeโฆ what even happens when you invert time and space? ๐ค
Normally a video is composed of several frames that represent a different instant of time, and shows a scene that evolves in the space captured by the frame. This filter is the antipode of that concept, taking inspiration from tilt and shift photography.
A filtered frame contains the whole timeline of events composing the sequence, and this is obtained by placing a slice of pixels from each frame into a single one. However โ since there are no infinite-width frames โ this is done up to the width of the input frame, and a video is recomposed by shifting away one column for each subsequent frame. In order to map space to time, the filter tilts each input frame as well, so that motion is preserved. This is accomplished by progressively selecting a different column from each input frame.
The end result is a sort of inverted parallax, so that far-away objects move much faster than the ones in the front. The ideal conditions for this video effect are when there's either very little motion and the background is static, or when there's a lot of motion and a very wide depth of field (e.g. wide panorama, while moving on a train). ๐โจ
The filter accepts the following parameters:
tiltโ tilt video while shifting (default). When unset, the video will be sliding a static image, composed of the first column of each frame.startโ what to do at the start of filtering (see below).endโ what to do at the end of filtering (see below).holdโ how many columns should pass through before start of filtering.padโ how many columns should be inserted before end of filtering.
Normally the filter shifts and tilts from the very first frame, and stops when the last one is received. However, before filtering starts, normal video may be preserved, so that the effect is slowly shifted in its place. Similarly, the last video frame may be reconstructed at the end. Alternatively it's possible to just start and end with black.
noneโ filtering starts immediately and ends when the last frame is received.frameโ the first frames or the very last frame are kept intact during processing.blackโ black is padded at the beginning or at the end of filtering.
tinterlace
Performs various types of temporal field interlacing. ๐
Frames are counted starting from 1, so the first input frame is considered odd. (Iconic numbering choice honestly.)
The filter accepts the following options:
modeโ specifies the mode of the interlacing. This option can also be specified as a value alone. See below for a list of values for this option.
Available values are:
merge,0โ move odd frames into the upper field, even into the lower field, generating a double height frame at half frame rate.
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
โฆand that last mode finishes off with this exact output:
11111 33333
22222 44444
11111 33333
22222 44444
11111 33333
22222 44444
11111 33333
22222 44444
okay now the rest of the modes, buckle up bestie ๐
drop_even, 1
Only outputs odd frames โ the even frames get dropped, and you get a frame with unchanged height but at half frame rate. slay, but make it half.
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
Output:
11111 33333
11111 33333
11111 33333
11111 33333
drop_odd, 2
The mirror twin ๐ช โ only outputs even frames, the odd ones get yeeted, unchanged height, half frame rate.
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
Output:
22222 44444
22222 44444
22222 44444
22222 44444
pad, 3
Expands each frame to full height, but the alternate lines get padded with black. Result: a frame with double height at the same input frame rate. it's giving letterbox but line-by-line ๐ค
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
Output:
11111 ..... 33333 .....
..... 22222 ..... 44444
11111 ..... 33333 .....
..... 22222 ..... 44444
11111 ..... 33333 .....
..... 22222 ..... 44444
11111 ..... 33333 .....
..... 22222 ..... 44444
interleave_top, 4
Interleaves the upper field from odd frames with the lower field from even frames โ unchanged height, half frame rate. the way it just โจmergesโจ
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111<- 22222 33333<- 44444
11111 22222<- 33333 44444<-
11111<- 22222 33333<- 44444
11111 22222<- 33333 44444<-
Output:
11111 33333
22222 44444
11111 33333
22222 44444
interleave_bottom, 5
The other way round, bestie: lower field from odd frames + upper field from even frames โ unchanged height, half frame rate.
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222<- 33333 44444<-
11111<- 22222 33333<- 44444
11111 22222<- 33333 44444<-
11111<- 22222 33333<- 44444
Output:
22222 44444
11111 33333
22222 44444
11111 33333
interlacex2, 6
Double frame rate, height unchanged ๐ Frames get inserted, each one containing the second temporal field from the previous input frame plus the first temporal field from the next input frame. This mode relies on the top_field_first flag. Useful for interlaced video displays with no field synchronisation โ iykyk.
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
Output:
11111 22222 22222 33333 33333 44444 44444
11111 11111 22222 22222 33333 33333 44444
11111 22222 22222 33333 33333 44444 44444
11111 11111 22222 22222 33333 33333 44444
mergex2, 7
Moves odd frames into the upper field, even into the lower field โ a double height frame at the same frame rate. absolute unit ๐ซถ
------> time
Input:
Frame 1 Frame 2 Frame 3 Frame 4
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
11111 22222 33333 44444
Output:
11111 33333 33333 55555
22222 22222 44444 44444
11111 33333 33333 55555
22222 22222 44444 44444
11111 33333 33333 55555
22222 22222 44444 44444
11111 33333 33333 55555
22222 22222 44444 44444
โ ๏ธ Numeric values are deprecated but are still accepted for backward compatibility reasons. So likeโฆ they work, but don't be that girl.
Default mode is "merge".
flags
Specifies flags that influence the filter process ๐ฉ
The available value for flags is:
low_pass_filter,vlpfโ enables linear vertical low-pass filtering in the filter. Vertical low-pass filtering is required when you're creating an interlaced destination from a progressive source that contains high-frequency vertical detail. The filtering reduces interlace 'twitter' and Moire patterning. (iconic behaviour honestly)complex_filter,cvlpfโ enables complex vertical low-pass filtering. This will slightly less reduce interlace 'twitter' and Moire patterning, but better retains detail and the subjective sharpness impression โจbypass_ilโ bypasses already interlaced frames and only adjusts the frame rate.
๐ heads up: vertical low-pass filtering and bypassing already interlaced frames can only be enabled for modeinterleave_topandinterleave_bottom. no exceptions bestie.
๐ง tmedian ๐ง
Picks median pixels from several successive input video frames. it's giving "majority vote but make it pixels" ๐ณ๏ธ
The filter accepts the following options:
radiusโ sets the radius of the median filter. Default is1. Allowed range is from1to127.planesโ sets which planes to filter. Default value is15, and with that all planes get processed.percentileโ sets the median percentile. Default value is0.5. That default0.5will always pick median values, while0picks minimum values and1picks maximum values.
Commands
This filter supports all above options as commands, excluding option radius. (sorry radius, you're not command-able ๐
)
๐ฆ tmidequalizer ๐ฆ
Applies the Temporal Midway Video Equalization effect.
Midway Video Equalization adjusts a sequence of video frames so they all have the same histograms, while maintaining their dynamics as much as possible. It's useful for e.g. matching exposures from a video frames sequence โ no cap, this one actually eats ๐ฅ
This filter accepts the following option:
radiusโ sets filtering radius. Default is5. Allowed range is from1to127.sigmaโ sets filtering sigma. Default is0.5. This controls the strength of filtering. Setting this option to0effectively does nothing (so don't bother, bestie ๐).planesโ sets which planes to process. Default is15, which is all available planes.
๐ tmix ๐
Mixes successive video frames ๐ like a smoothie but for pixels.
A description of the accepted options follows.
framesโ the number of successive frames to mix. If unspecified, it defaults to3.weightsโ specifies the weight of each input video frame. Each weight is separated by space. If the number of weights is smaller than the number offrames, the last specified weight will be used for all the remaining unset weights.scaleโ specifies the scale. If it's set, it gets multiplied with the sum of each weight multiplied with pixel values, giving the final destination pixel value. By defaultscaleis auto scaled to the sum of weights.planesโ sets which planes to filter. Default is all. Allowed range is from0to15.
Examples
- Average 7 successive frames:
tmix=frames=7:weights="1 1 1 1 1 1 1"
- Apply simple temporal convolution:
tmix=frames=3:weights="-1 3 -1"
- Similar as above but only showing temporal differences:
tmix=frames=3:weights="-1 2 -1":scale=1
Commands
This filter supports the following commands:
weightsscaleplanes
Syntax is the same as the option with the same name ๐
๐ธ tonemap โ tone map colors from different dynamic ranges
okay so this one is genuinely iconic for HDR girlies: it tone maps colors from different dynamic ranges ๐
Real talk though โ this filter expects data in single precision floating point, because it literally needs to operate on (and can output) out-of-range values. So you need another filter, like zscale, to convert the resulting frame back into a usable format. It's giving relay race ๐โโ๏ธ
Also important: the tonemapping algorithms implemented only work on linear light, so your input data should be linearized beforehand (and possibly correctly tagged). No skipping steps bestie ๐ญ
ffmpeg -i INPUT -vf zscale=transfer=linear,tonemap=clip,zscale=transfer=bt709,format=yuv420p OUTPUT
โจ Options
The filter accepts the following options.
tonemapโ Set the tone map algorithm to use. Possible values are:noneโ Do not apply any tone map, only desaturate overbright pixels.clipโ Hard-clip any out-of-range values. Use it for perfect color accuracy for in-range values, while distorting out-of-range values.linearโ Stretch the entire reference gamut to a linear multiple of the display.gammaโ Fit a logarithmic transfer between the tone curves.reinhardโ Preserve overall image brightness with a simple curve, using nonlinear contrast, which results in flattening details and degrading color accuracy.hableโ Preserve both dark and bright details better thanreinhard, at the cost of slightly darkening everything. Use it when detail preservation is more important than color and brightness accuracy.mobiusโ Smoothly map out-of-range values, while retaining contrast and colors for in-range material as much as possible. Use it when color accuracy is more important than detail preservation.
Default is none.
paramโ Tune the tone mapping algorithm. This affects the following algorithms:noneโ Ignored. (she said "not today" ๐)linearโ Specifies the scale factor to use while stretching. Default to1.0.gammaโ Specifies the exponent of the function. Default to1.8.clipโ Specify an extra linear coefficient to multiply into the signal before clipping. Default to1.0.reinhardโ Specify the local contrast coefficient at the display peak. Default to0.5, which means that in-gamut values will be about half as bright as when clipping.hableโ Ignored.mobiusโ Specify the transition point from linear to mobius transform. Every value below this point is guaranteed to be mapped 1:1. The higher the value, the more accurate the result will be, at the cost of losing bright details. Default to0.3, which due to the steep initial slope still preserves in-range colors fairly accurately.
desatโ Apply desaturation for highlights that exceed this level of brightness. The higher the parameter, the more color information will be preserved. This setting helps prevent unnaturally blown-out colors for super-highlights, by (smoothly) turning into white instead. This makes images feel more natural, at the cost of reducing information about out-of-range colors.
The default of 2.0 is somewhat conservative and will mostly just apply to skies or directly sunlit surfaces. A setting of 0.0 disables this option.
This option works only if the input frame has a supported color tag. iykyk ๐ซถ
peakโ Override signal/nominal/reference peak with this value. Useful when the embedded peak information in display metadata is not reliable or when tone mapping from a lower range to a higher range.
๐ tpad โ temporarily pad video frames
Like a little breather for your video stream. The filter accepts the following options:
startโ Specify number of delay frames before input video stream. Default is0.stopโ Specify number of padding frames after input video stream. Set to-1to pad indefinitely. Default is0.start_modeโ Set kind of frames added to beginning of stream. Can be eitheraddorclone. Withaddframes of solid-color are added. Withcloneframes are clones of first frame. Default isadd.stop_modeโ Set kind of frames added to end of stream. Can be eitheraddorclone. Withaddframes of solid-color are added. Withcloneframes are clones of last frame. Default isadd.start_duration,stop_durationโ Specify the duration of the start/stop delay. See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. These options overridestartandstop. Default is0.colorโ Specify the color of the padded area. For the syntax of this option, check the "Color" section in theffmpeg-utilsmanual.
The default value of color is "black".
๐ฆ transpose โ transpose rows with columns in the input video and optionally flip it
It accepts the following parameters:
dirโ Specify the transposition direction.
Can assume the following values:
0,4,cclock_flipโ Rotate by 90 degrees counterclockwise and vertically flip (default), that is:
L.R L.l
. . -> . .
l.r R.r
1,5,clockโ Rotate by 90 degrees clockwise, that is:
L.R l.L
. . -> . .
l.r r.R
2,6,cclockโ Rotate by 90 degrees counterclockwise, that is:
L.R R.r
. . -> . .
l.r L.l
3,7,clock_flipโ Rotate by 90 degrees clockwise and vertically flip, that is:
L.R r.R
. . -> . .
l.r l.L
For values between 4-7, the transposition is only done if the input video geometry is portrait and not landscape. These values are deprecated, the passthrough option should be used instead.
Numerical values are deprecated, and should be dropped in favor of symbolic constants. (she's retired, use the names ๐ )
passthroughโ Do not apply the transposition if the input geometry matches the one specified by the specified value. It accepts the following values:noneโ Always apply transposition.portraitโ Preserve portrait geometry (whenheight>=width).landscapeโ Preserve landscape geometry (whenwidth>=height).
Default value is "none".
For example to rotate by 90 degrees clockwise and preserve portrait layout:
transpose=dir=1:passthrough=portrait
The command above can also be specified as:
transpose=1:portrait
โจ trim โ trim the input so that the output contains one continuous subpart of the input
It accepts the following parameters:
startโ Specify the time of the start of the kept section, i.e. the frame with the timestamp start will be the first frame in the output.endโ Specify the time of the first frame that will be dropped, i.e. the frame immediately preceding the one with the timestamp end will be the last frame in the output.start_ptsโ This is the same asstart, except this option sets the start timestamp in timebase units instead of seconds.end_ptsโ This is the same asend, except this option sets the end timestamp in timebase units instead of seconds.durationโ The maximum duration of the output in seconds.start_frameโ The number of the first frame that should be passed to the output.end_frameโ The number of the first frame that should be dropped.
start, end, and duration are expressed as time duration specifications; see the Time duration section in the ffmpeg-utils(1) manual for the accepted syntax.
Note that the first two sets of thestart/endoptions and thedurationoption look at the frame timestamp, while the_framevariants simply count the frames that pass through the filter. Also note that this filter does not modify the timestamps. If you wish for the output timestamps to start at zero, insert asetptsfilter after thetrimfilter.
If multiple start or end options are set, this filter tries to be greedy and keep all the frames that match at least one of the specified constraints. To keep only the part that matches all the constraints at once, chain multiple trim filters. (fr fr, she's an overachiever ๐ญ)
The defaults are such that all the input is kept. So it is possible to set e.g. just the end values to keep everything before the specified time.
Examples:
- Drop everything except the second minute of input:
ffmpeg -i INPUT -vf trim=60:120
- Keep only the first second:
ffmpeg -i INPUT -vf trim=duration=1
๐ unpremultiply โ apply alpha unpremultiply effect to input video stream using first plane of second stream as alpha
Both streams must have same dimensions and same pixel format. (matching outfits only bestie ๐ฏโโ๏ธ)
The filter accepts the following option:
planesโ Set which planes will be processed, unprocessed planes will be copied. By default value0xf, all planes will be processed.
If the format has 1 or 2 components, then luma is bit 0. If the format has 3 or 4 components: for RGB formats bit 0 is green, bit 1 is blue and bit 2 is red; for YUV formats bit 0 is luma, bit 1 is chroma-U and bit 2 is chroma-V. If present, the alpha channel is always the last bit.
inplaceโ Do not require 2nd input for processing, instead use alpha plane from input stream. (solo mode, main character energy ๐)
๐ฅ unsharp โ sharpen or blur the input video
It accepts the following parameters:
luma_msize_x,lxโ Set the luma matrix horizontal size. It must be an odd integer between3and23. The default value is5.luma_msize_y,lyโ Set the luma matrix vertical size. It must be an odd integer between3and23. The default value is5.luma_amount,laโ Set the luma effect strength. It must be a floating point number, reasonable values lay between-1.5and1.5.
Negative values will blur the input video, while positive values will sharpen it, a value of zero will disable the effect.
Default value is 1.0.
chroma_msize_x,cxโ Set the chroma matrix horizontal size. It must be an odd integer between3and23. The default value is5.chroma_msize_y,cyโ Set the chroma matrix vertical size. It must be an odd integer between3and23. The default value is5.chroma_amount,caโ Set the chroma effect strength. It must be a floating point number, reasonable values lay between-1.5and1.5.
Negative values blur the input video, while positive values sharpen it โ and a value of 0 disables the effect entirely, no cap.
Default value is 0.0. ๐ซถ
alpha_msize_x,axโ sets the alpha matrix horizontal size. Gotta be an odd integer between3and23, bestie. Default value is5. โจalpha_msize_y,ayโ sets the alpha matrix vertical size. Also an odd integer between3and23. Default value is5. ๐alpha_amount,aaโ sets the alpha effect strength. Must be a floating point number, and the reasonable values live between-1.5and1.5.
Negative values blur the input video, positive values sharpen it, and 0 means no effect at all.
Default value is 0.0.
All the parameters are optional, and they default to the equivalent of the string '5:5:1.0:5:5:0.0'. ๐
Examples
- Apply a strong luma sharpen effect โ iconic behaviour fr:
unsharp=luma_msize_x=7:luma_msize_y=7:luma_amount=2.5
- Apply a strong blur of both luma and chroma parameters โ the way this one goes blurry on purpose:
unsharp=7:7:-2:7:7:-2
untile
Decomposes a video that's made of tiled images into the individual images. Like, un-tiling it. ๐งฉ
The frame rate of the output video is the frame rate of the input video multiplied by the number of tiles โ yes really, it speeds up like that.
This filter does the exact reverse of tile.
The filter accepts the following options:
layoutโ sets the grid size (i.e. the number of lines and columns). For the syntax of this option, go check the "Video size" section in theffmpeg-utilsmanual. ๐
Examples
- Produce a 1-second video from a still image file made of 25 frames stacked vertically, like an analogic film reel โ vintage film-girl energy, obsessed:
ffmpeg -r 1 -i image.jpg -vf untile=1x25 movie.mkv
uspp
Applies the ultra slow/simple postprocessing filter, which compresses and decompresses the image at several shifts (or โ in the case of quality level 8 โ all of them) and averages the results. ๐ซ
The way this differs from the behaviour of spp is that uspp actually encodes & decodes each case with libavcodec Snow, whereas spp uses a simplified intra only 8x8 DCT similar to MJPEG. iykyk.
Heads up bestie: this filter is not available in ffmpeg versions between5.0and6.0. ๐ญ
The filter accepts the following options:
qualityโ sets quality. This option defines the number of levels for averaging. It accepts an integer in the range0-8. If you set it to0, the filter just has no effect. A value of8means the higher quality. And for each increment of that value, the speed drops by a factor of approximately2. Default value is3. ๐ฎโ๐จqpโ force a constant quantization parameter. If it's not set, the filter will use the QP from the video stream (if available).codecโ use the specified codec instead ofsnow.
v360
Converts 360 videos between all the various formats. This one is a whole personality, buckle up. ๐
The filter accepts the following options:
inputoutputโ set the format of the input/output video.
Available formats:
e,equirectโ equirectangular projection.c3x2,c6x1,c1x6โ cubemap with3x2/6x1/1x6layout.
Format specific options:
in_padout_padโ set the padding proportion for the input/output cubemap. Values in decimals.
Example values:
0โ no padding.0.01โ 1% of the face is padding. For example, with1920x1280resolution the face size would be640x640and the padding would be3pixels from each side. (640 * 0.01 = 6pixels)
Default value is 0. Maximum value is 0.1. ๐ฅ
fin_padfout_padโ set fixed padding for the input/output cubemap. Values in pixels.
Default value is 0. If it's greater than zero, it overrides the other padding options.
in_forderout_forderโ set the order of faces for the input/output cubemap. Choose one direction for each position.
Designation of directions:
rโ rightlโ leftuโ updโ downfโ forwardbโ back
Default value is rludfb. ๐
in_frotout_frotโ set the rotation of faces for the input/output cubemap. Choose one angle for each position.
Designation of angles:
0โ 0 degrees clockwise1โ 90 degrees clockwise2โ 180 degrees clockwise3โ 270 degrees clockwise
Default value is 000000.
eacโ Equi-Angular Cubemap.flat,gnomonic,rectilinearโ regular video. Like, normal-normal.
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view. ๐
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
dfisheyeโ dual fisheye.
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
barrel,fb,barrelsplitโ Facebook's 360 formats. ๐ฆsgโ stereographic format.
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
mercatorโ Mercator format.ballโ ball format, gives significant distortion toward the back.hammerโ Hammer-Aitoff map projection format.sinusoidalโ sinusoidal map projection format.fisheyeโ fisheye projection.
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
panniniโ Pannini projection.
Format specific options:
h_fovโ set the output pannini parameter.ih_fovโ set the input pannini parameter.
cylindricalโ cylindrical projection. ๐
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
perspectiveโ perspective projection. (output only)
Format specific options:
v_fovโ set perspective parameter.
tetrahedronโ tetrahedron projection.tspโ truncated square pyramid projection.he,hequirectโ half equirectangular projection.equisolidโ equisolid format.
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ogโ orthographic format.
Format specific options:
h_fovv_fovd_fovโ set the output horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
ih_foviv_fovid_fovโ set the input horizontal/vertical/diagonal field of view. Values in degrees.
If the diagonal field of view is set, it overrides the horizontal and vertical field of view.
octahedronโ octahedron projection.cylindricaleaโ Cylindrical Equal Area projection. โจ
interpโ sets the interpolation method. Note: more complex interpolation methods require much more memory to run. You've been warned, bestie. ๐
Available methods:
near,nearestโ nearest neighbour.line,linearโ bilinear interpolation.lagrange9โ Lagrange9 interpolation.cube,cubicโ bicubic interpolation.lanc,lanczosโ Lanczos interpolation.sp16,spline16โ Spline16 interpolation.gauss,gaussianโ Gaussian interpolation.mitchellโ Mitchell interpolation. ๐
Default value is line.
whโ set the output video resolution. The default resolution depends on formats.in_stereoout_stereoโ set the input/output stereo format:2dโ 2D monosbsโ side by sidetbโ top bottom
Default value is 2d for both input and output format.
yawpitchrollโ set rotation for the output video. Values are in degrees.rorderโ set rotation order for the output video. Pick one item for each position:y,Yโ yawp,Pโ pitchr,Rโ roll
Default value is ypr.
h_flipv_flipd_flipโ flip the output video horizontally (swaps left-right) / vertically (swaps up-down) / in-depth (swaps back-forward). Boolean values.ih_flipiv_flipโ set if the input video is flipped horizontally / vertically. Boolean values.in_transโ set if the input video is transposed. Boolean value, by default disabled.out_transโ set if the output video needs to be transposed. Boolean value, by default disabled.h_offsetv_offsetโ set output horizontal / vertical off-axis offset. Default is set to 0. Allowed range is from-1to1.alpha_maskโ build a mask in the alpha plane for all unmapped pixels by marking them fully transparent. Boolean value, by default disabled.reset_rotโ reset the rotation of the output video. Boolean value, by default disabled.
Examples ๐
- Convert equirectangular video to cubemap with 3x2 layout and 1% padding using bicubic interpolation:
ffmpeg -i input.mkv -vf v360=e:c3x2:cubic:out_pad=0.01 output.mkv
- Extract back view of Equi-Angular Cubemap:
ffmpeg -i input.mkv -vf v360=eac:flat:yaw=180 output.mkv
- Convert transposed and horizontally flipped Equi-Angular Cubemap in side-by-side stereo format to equirectangular top-bottom stereo format:
v360=eac:equirect:in_stereo=sbs:in_trans=1:ih_flip=1:out_stereo=tb
Commands ๐
This filter supports a subset of the above options as commands.
vaguedenoiser
Bestie, this one applies a wavelet based denoiser. โจ
So what it does: it transforms each frame from the video input into the wavelet domain, using Cohen-Daubechies-Feauveau 9/7. Then it applies some filtering to the obtained coefficients. Then it does an inverse wavelet transform after. Because wavelet properties are lowkey iconic, it should give you a nice smoothed result, and reduced noise, without blurring picture features. No cap.
This filter accepts the following options:
thresholdโ the filtering strength. The higher it is, the more filtered the video will be. Hard thresholding can use a higher threshold than soft thresholding before the video looks overfiltered. Default value is2.methodโ the filtering method the filter will use. It accepts the following values:hardโ all values under the threshold will be zeroed.softโ all values under the threshold will be zeroed. All values above will be reduced by the threshold.garroteโ scales or nullifies coefficients โ intermediary between (more) soft and (less) hard thresholding.
Default is garrote.
nstepsโ number of times the wavelet will decompose the picture. The picture can't be decomposed beyond a particular point (typically, 8 for a 640x480 frame โ as 2^9 = 512 > 480). Valid values are integers between1and32. Default value is6.percentโ partial of full denoising (limited coefficients shrinking), from0to100. Default value is85.planesโ a list of the planes to process. By default all planes are processed.typeโ the threshold type the filter will use. It accepts the following values:universalโ threshold used is same for all decompositions.bayesโ threshold used depends also on each decomposition coefficients.
Default is universal.
varblur
Apply a variable blur filter by using the 2nd video stream to set the blur radius. Heads up: the 2nd stream must have the same dimensions. ๐ซถ
This filter accepts the following options:
min_rโ set min allowed radius. Allowed range is from0to254. Default is0.max_rโ set max allowed radius. Allowed range is from1to255. Default is8.planesโ set which planes to process. By default, all are used.
The varblur filter also supports the framesync options.
Commands
This filter supports all the above options as commands.
vectorscope
Display 2 color component values in the two dimensional graph (which is called a vectorscope). Honestly? So satisfying to look at. ๐
This filter accepts the following options:
mode,mโ set vectorscope mode. It accepts the following values:graytintโ gray values are displayed on graph, higher brightness means more pixels have the same component color value on location in graph. This is the default mode.colorโ gray values are displayed on graph. Surrounding pixels values which are not present in video frame are drawn in gradient of 2 color components which are set by optionxandy. The 3rd color component is static.color2โ actual color components values present in video frame are displayed on graph.color3โ similar ascolor2but higher frequency of same valuesxandyon graph increases value of another color component, which is luminance by default values ofxandy.color4โ actual colors present in video frame are displayed on graph. If two different colors map to same position on graph then color with higher value of component not present in graph is picked.color5โ gray values are displayed on graph. Similar tocolorbut with 3rd color component picked from radial gradient.
xโ set which color component will be represented on X-axis. Default is1.yโ set which color component will be represented on Y-axis. Default is2.intensity,iโ set intensity, used by modes:gray,color,color3andcolor5for increasing brightness of color component which represents frequency of (X, Y) location in graph.envelope,e:noneโ no envelope, this is default.instantโ instant envelope, even the darkest single pixel will be clearly highlighted.peakโ hold maximum and minimum values presented in graph over time. This way you can still spot out of range values without constantly looking at vectorscope.peak+instantโ peak and instant envelope combined together.
graticule,gโ set what kind of graticule to draw:nonegreencolorinvert
opacity,oโ set graticule opacity.flags,fโ set graticule flags:whiteโ draw graticule for white point.blackโ draw graticule for black point.nameโ draw color points short names.
bgopacity,bโ set background opacity.lthreshold,lโ set low threshold for color component not represented on X or Y axis. Values lower than this value will be ignored. Default is0. Note this value is multiplied with actual max possible value one pixel component can have. So for 8-bit input and low threshold value of0.1actual threshold is0.1 * 255 = 25.hthreshold,hโ set high threshold for color component not represented on X or Y axis. Values higher than this value will be ignored. Default is1. Note this value is multiplied with actual max possible value one pixel component can have. So for 8-bit input and high threshold value of0.9actual threshold is0.9 * 255 = 230.colorspace,cโ set what kind of colorspace to use when drawing graticule:auto601709
Default is auto.
tint0,t0tint1,t1โ set color tint forgray/tintvectorscope mode. By default both options are zero. This means no tint, and output will remain gray.
vidstabdetect
Analyze video stabilization/deshaking. Perform pass 1 of 2, see vidstabtransform for pass 2. ๐ฌ
This filter generates a file with relative translation and rotation transform information about subsequent frames, which is then used by the vidstabtransform filter.
To enable compilation of this filter you need to configure FFmpeg with --enable-libvidstab. Don't skip this bestie, it will not build otherwise. ๐
This filter accepts the following options:
resultโ set the path to the file used to write the transforms information. Default value istransforms.trf.shakinessโ set how shaky the video is and how quick the camera is. It accepts an integer in the range1-10, a value of1means little shakiness, a value of10means strong shakiness. Default value is5.accuracyโ set the accuracy of the detection process. It must be a value in the range1-15. A value of1means low accuracy, a value of15means high accuracy. Default value is15.stepsizeโ set stepsize of the search process. The region around minimum is scanned with 1 pixel resolution. Default value is6.mincontrastโ set minimum contrast. Below this value a local measurement field is discarded. Must be a floating point value in the range0-1. Default value is0.3.tripodโ set reference frame number for tripod mode.
If enabled, the motion of the frames is compared to a reference frame in the filtered stream, identified by the specified number. The idea is to compensate all movements in a more-or-less static scene and keep the camera view absolutely still.
If set to 0, it is disabled. The frames are counted starting from 1.
showโ show fields and transforms in the resulting frames. It accepts an integer in the range0-2. Default value is0, which disables any visualization.fileformatโ format for the transforms data file to be written. Acceptable values are:asciiโ human-readable plain textbinaryโ binary format, roughly 40% smaller thanascii. (default)
Examples ๐ฆ
- Use default values:
vidstabdetect
- Analyze strongly shaky movie and put the results in file
mytransforms.trf:
vidstabdetect=shakiness=10:accuracy=15:result="mytransforms.trf"
- Visualize the result of internal transformations in the resulting video:
vidstabdetect=show=1
- Analyze a video with medium shakiness using
ffmpeg:
ffmpeg -i input -vf vidstabdetect=shakiness=5:show=1 dummy.avi
๐ vidstabtransform
Video stabilization/deshaking: pass 2 of 2, see vidstabdetect for pass 1.
So basically this one reads a file full of transform info for each frame and then applies/compensates them. Pair it with the vidstabdetect filter and you can deshake your videos, bestie. See also <http://public.hronopik.de/vid.stab>. And listen โ it is important to also use the unsharp filter, see below. Not optional-optional, like actually important.
To enable compilation of this filter you need to configure FFmpeg with --enable-libvidstab.
Options
inputโ sets the path to the file we read the transforms from. Default value istransforms.trf.smoothingโ sets the number of frames (value*2 + 1) used for lowpass filtering the camera movements. Default value is10.
So for example a number of 10 means 21 frames get used (10 in the past and 10 in the future) to smoothen the motion in the video. A larger value gives you a smoother video, but it limits the acceleration of the camera (pan/tilt movements). 0 is that special case where a static camera is simulated.
optalgoโ sets the camera path optimization algorithm.
Accepted values are:
gaussโ gaussian kernel low-pass filter on camera motion (default)avgโ averaging on transformations
maxshiftโ sets the maximal number of pixels to translate frames. Default value is-1, meaning no limit.maxangleโ sets the maximal angle in radians (degree*PI/180) to rotate frames. Default value is-1, meaning no limit.cropโ specifies how to deal with borders that may be visible due to movement compensation.
Available values are:
keepโ keep image information from previous frame (default)blackโ fill the border black
invertโ invert transforms if set to1. Default value is0.relativeโ consider transforms as relative to previous frame if set to1, absolute if set to0. Default value is0.zoomโ sets percentage to zoom. A positive value gives you a zoom-in effect, a negative value a zoom-out effect. Default value is0(no zoom).optzoomโ sets optimal zooming to avoid borders.
Accepted values are:
0โ disabled1โ optimal static zoom value is determined (only very strong movements will lead to visible borders) (default)2โ optimal adaptive zoom value is determined (no borders will be visible), seezoomspeed
Note that the value you give at zoom gets added to the one calculated here. Math!
zoomspeedโ sets percent to zoom maximally each frame (enabled whenoptzoomis set to2). Range is from0to5, default value is0.25.interpolโ specifies the type of interpolation.
Available values are:
noโ no interpolationlinearโ linear only horizontalbilinearโ linear in both directions (default)bicubicโ cubic in both directions (slow)
tripodโ enable virtual tripod mode if set to1, which is equivalent torelative=0:smoothing=0. Default value is0.
Also use the tripod option of vidstabdetect. Teamwork ๐
debugโ increase log verbosity if set to1. Also the detected global motions get written to the temporary fileglobal_motions.trf. Default value is0.
Examples
- Use
ffmpegfor a typical stabilization with default values:
ffmpeg -i inp.mpeg -vf vidstabtransform,unsharp=5:5:0.8:3:3:0.4 inp_stabilized.mpeg
Note the use of the unsharp filter, which is always recommended. Always. ๐ซถ
- Zoom in a bit more and load transform data from a given file:
vidstabtransform=zoom=5:input="mytransforms.trf"
- Smoothen the video even more:
vidstabtransform=smoothing=30
๐ธ vflip
Flips the input video vertically. That's it, that's the whole vibe. Upside-down era.
For example, to vertically flip a video with ffmpeg:
ffmpeg -i in.avi -vf "vflip" out.avi
๐ฆ vfrdet
Detects variable frame rate video. โจ
This filter tries to detect if the input is variable or constant frame rate.
At the end it will output the number of frames detected as having variable delta pts, and ones with constant delta pts. And if there were frames with variable delta, then it will also show the min, max and average delta encountered. Receipts! ๐
๐ vibrance
Boost or alter saturation. Iconic little color filter, ngl.
The filter accepts the following options:
intensityโ sets the strength of the boost if it's a positive value, or the strength of the alter if it's a negative value. Default is0. Allowed range is from-2to2.rbalโ sets the red balance. Default is1. Allowed range is from-10to10.gbalโ sets the green balance. Default is1. Allowed range is from-10to10.bbalโ sets the blue balance. Default is1. Allowed range is from-10to10.rlumโ sets the red luma coefficient.glumโ sets the green luma coefficient.blumโ sets the blue luma coefficient.alternateโ ifintensityis negative and this is set to1, colors will change; otherwise colors will be less saturated, more towards gray.
Commands
This filter supports all of the above options as commands. Yes bestie, runtime control, we love to see it. ๐
๐ฅ vif
Obtains the average VIF (Visual Information Fidelity) between two input videos.
This filter takes two input videos. Two! It's a two-input filter, okay?
Both input videos must have the same resolution and pixel format for this filter to work correctly. It also assumes both inputs have the same number of frames, which get compared one by one. No skipping ahead, no falling behind. ๐
The obtained average VIF score gets printed through the logging system.
The filter stores the calculated VIF score of each frame.
This filter also supports the framesync options.
In the below example the input file main.mpg being processed is compared with the reference file ref.mpg:
ffmpeg -i main.mpg -i ref.mpg -lavfi vif -f null -
๐ง vignette
Makes or reverses a natural vignetting effect. Aesthetic af.
The filter accepts the following options:
angle,aโ set lens angle expression as a number of radians.
The value gets clipped in the [0,PI/2] range.
Default value: PI/5
x0,y0โ set center coordinates expressions. Respectivelyw/2andh/2by default.modeโ set forward/backward mode.
Available modes are:
forwardโ the larger the distance from the central point, the darker the image becomes.backwardโ the larger the distance from the central point, the brighter the image becomes. This can be used to reverse a vignette effect, though there is no automatic detection to extract the lens angle and other settings (yet). It can also be used to create a burning effect.
Default value is forward.
evalโ set evaluation mode for the expressions (angle,x0,y0).
It accepts the following values:
initโ evaluate expressions only once during the filter initialization.frameโ evaluate expressions for each incoming frame. This is way slower than theinitmode since it requires all the scalers to be re-computed, but it allows advanced dynamic expressions.
Default value is init.
ditherโ set dithering to reduce the circular banding effects. Default is1(enabled).aspectโ set vignette aspect. This setting allows one to adjust the shape of the vignette. Setting this value to the SAR of the input will make a rectangular vignetting following the dimensions of the video.
Default is 1/1.
Expressions
The alpha, x0 and y0 expressions can contain the following parameters.
w,hโ input width and heightnโ the number of input frame, starting from0ptsโ the PTS (Presentation TimeStamp) time of the filtered video frame, expressed in TB units,NANif undefinedrโ frame rate of the input video,NANif the input frame rate is unknowntโ the PTS (Presentation TimeStamp) of the filtered video frame, expressed in seconds,NANif undefinedtbโ time base of the input video
Examples
- Apply a simple strong vignetting effect:
vignette=PI/4
- Make a flickering vignetting:
vignette='PI/4+random(1)*PI/50':eval=frame
๐ vmafmotion
Obtains the average VMAF motion score of a video. It's one of the component metrics of VMAF. Little metric, big job.
The obtained average motion score gets printed through the logging system.
The filter accepts the following options:
stats_fileโ if specified, the filter will use the named file to save the motion score of each frame with respect to the previous frame. When filename equals-the data is sent to standard output.
Example:
ffmpeg -i ref.mpg -vf vmafmotion -f null -
๐ vpp_amf
Scale (resize) and convert colorspace, transfer characteristics or color primaries for the input video, using the AMD Advanced Media Framework library for hardware acceleration. GPU go brrr. โก Setting the output width and height works in the same way as for the scale filter.
The filter accepts the following options:
w,hโ set the output video dimension expression. Default value is the input dimension.
Allows for the same expressions as the scale filter.
scale_typeโ sets the algorithm used for scaling:bilinearโ Bilinear
This is the default.
bicubicโ Bicubic
formatโ controls the output pixel format. By default, or if none is specified, the input pixel format is used.force_original_aspect_ratio,force_divisible_byโ work the same as the identicalscalefilter options.reset_sarโ works the same as the identicalscalefilter option.color_profileโ specify all color properties at once.
The accepted values are:
bt601โ BT.601bt709โ BT.709bt2020โ BT.2020
trcโ specify output transfer characteristics.
The accepted values are:
bt709โ BT.709gamma22โ constant gamma of 2.2gamma28โ constant gamma of 2.8smpte170mโ SMPTE-170Msmpte240mโ SMPTE-240Mlinearโ LinearlogLOGlog-sqrtโ LOG_SQRTiec61966-2-4โ iec61966-2-4bt1361-ecgโ BT1361_ECGiec61966-2-1โ iec61966-2-1bt2020-10โ BT.2020 for 10-bits contentbt2020-12โ BT.2020 for 12-bits content
smpte2084โ SMPTE2084, the HDR one ๐smpte428โ SMPTE428arib-std-b67โ ARIB_STD_B67
๐จ primaries
Tell it what the output color primaries are, bestie โ this is the "what do pure red/green/blue actually look like" of it all. Accepted values:
bt709โ BT.709bt470mโ BT.470Mbt470bgโ BT.470BG or BT.601-6 625smpte170mโ SMPTE-170M or BT.601-6 525smpte240mโ SMPTE-240Mfilmโ filmbt2020โ BT.2020smpte428โ SMPTE-428smpte431โ SMPTE-431smpte432โ SMPTE-432jedec-p22โ JEDEC P22 phosphors
โจ Examples
- Scale input to 720p, keeping aspect ratio and ensuring the output is
yuv420pโ the classic glow-up ๐
vpp_amf=-2:720:format=yuv420p
- Upscale to 4K and change color profile to
bt2020โ main character energy, huge canvas ๐ฆ
vpp_amf=4096:2160:color_profile=bt2020
๐ฅ vstack
Stacks your input videos vertically, one on top of the other, like a little video sandwich ๐ฅช
All streams must be of same pixel format and of same width โ no cap, that's a hard requirement.
Fun fact: this filter is faster than using overlay and pad filter to create the same output. Slay, efficiency.
It accepts the following options:
inputsโ Set number of input streams. Default is2.shortestโ If set to1, force the output to terminate when the shortest input terminates. Default value is0.
๐๏ธ w3fdif
Deinterlace the input video โ and yes, "w3fdif" stands for "Weston 3 Field Deinterlacing Filter", iykyk.
Based on the process described by Martin Weston for BBC R&D, and implemented based on the de-interlace algorithm written by Jim Easterbrook for BBC R&D, the Weston 3 field deinterlacing filter uses filter coefficients calculated by BBC R&D. Literally BBC-approved deinterlacing, iconic ๐
This filter uses field-dominance information in frame to decide which of each pair of fields to place first in the output. If it gets it wrong use setfield filter before "w3fdif" filter โ noted, bestie ๐ซถ
There are two sets of filter coefficients, so called "simple" and "complex". Which set of filter coefficients is used can be set by passing an optional parameter:
filterโ Set the interlacing filter coefficients. Accepts one of the following values:simpleโ Simple filter coefficient set.complexโ More-complex filter coefficient set.
Default value is complex.
modeโ The interlacing mode to adopt. It accepts one of the following values:frameโ Output one frame for each frame.fieldโ Output one frame for each field.
The default value is "field".
parityโ The picture field parity assumed for the input interlaced video. It accepts one of the following values:tffโ Assume the top field is first.bffโ Assume the bottom field is first.autoโ Enable automatic detection of field parity.
The default value is "auto". If the interlacing is unknown or the decoder does not export this information, top field first will be assumed.
deintโ Specify which frames to deinterlace. Accepts one of the following values:allโ Deinterlace all frames,interlacedโ Only deinterlace frames marked as interlaced.
Default value is all.
Commands
This filter supports same commands as options โ cute and consistent ๐
๐ waveform
Video waveform monitor. It plots color component intensity โ by default luma only. Each column of the waveform corresponds to a column of pixels in the source video.
It accepts the following options:
mode,mโ Can be either"row", or"column". Default is"column". In row mode, the graph on the left side represents color component value0and the right side represents value =255. In column mode, the top side represents color component value =0and bottom side represents value =255.intensity,iโ Set intensity. Smaller values are useful to find out how many values of the same luminance are distributed across input rows/columns. Default value is0.04. Allowed range is[0, 1].mirror,rโ Set mirroring mode.0means unmirrored,1means mirrored. In mirrored mode, higher values will be represented on the left side for"row"mode and at the top for"column"mode. Default is1(mirrored).display,dโ Set display mode. It accepts the following values:overlayโ Presents information identical to that in the"parade", except that the graphs representing color components are superimposed directly over one another. This display mode makes it easier to spot relative differences or similarities in overlapping areas of the color components that are supposed to be identical, such as neutral whites, grays, or blacks.stackโ Display separate graph for the color components side by side in"row"mode or one below the other in"column"mode.paradeโ Display separate graph for the color components side by side in"column"mode or one below the other in"row"mode. Using this display mode makes it easy to spot color casts in the highlights and shadows of an image, by comparing the contours of the top and the bottom graphs of each waveform. Since whites, grays, and blacks are characterized by exactly equal amounts of red, green, and blue, neutral areas of the picture should display three waveforms of roughly equal width/height. If not, the correction is easy to perform by making level adjustments the three waveforms.
Default is "stack".
components,cโ Set which color components to display. Default is1, which means only luma or red color component if input is in RGB colorspace. If is set for example to7it will display all 3 (if) available color components.envelope,enoneโ No envelope, this is default.instantโ Instant envelope, minimum and maximum values presented in graph will be easily visible even with small"step"value.peakโ Hold minimum and maximum values presented in graph across time. This way you can still spot out of range values without constantly looking at waveforms.peak+instantโ Peak and instant envelope combined together.
filter,flowpassโ No filtering, this is default.flatโ Luma and chroma combined together.aflatโ Similar as above, but shows difference between blue and red chroma.xflatโ Similar as above, but use different colors.yflatโ Similar as above, but again with different colors.chromaโ Displays only chroma.colorโ Displays actual color value on waveform.acolorโ Similar as above, but with luma showing frequency of chroma values.
graticule,gโ Set which graticule to display.noneโ Do not display graticule.greenโ Display green graticule showing legal broadcast ranges.orangeโ Display orange graticule showing legal broadcast ranges.invertโ Display invert graticule showing legal broadcast ranges.
opacity,oโ Set graticule opacity.flags,flโ Set graticule flags.numbersโ Draw numbers above lines. By default enabled.dotsโ Draw dots instead of lines.
scale,sโ Set scale used for displaying graticule.digitalmillivoltsire
Default is digital.
bgopacity,bโ Set background opacity.tint0,t0tint1,t1
Set tint for output. Only used with lowpass filter and when display is not overlay and input pixel formats are not RGB.
fitmode,fmโ Set sample aspect ratio of video output frames. Can be used to configure waveform so it is not stretched too much in one of directions.noneโ Set sample aspect ration to 1/1.sizeโ Set sample aspect ratio to match input size of video
Default is none.
inputโ Set input formats for filter to pick from. Can beall, for selecting from all available formats, orfirst, for selecting first available format. Default isfirst.
๐ชก weave, doubleweave
The "weave" takes a field-based video input and join each two sequential fields into single frame, producing a new double height clip with half the frame rate and half the frame count. It's giving loom energy ๐งถ
The "doubleweave" works same as "weave" but without halving frame rate and frame count.
It accepts the following option:
first_fieldโ Set first field. Available values are:top,tโ Set the frame as top-field-first.bottom,bโ Set the frame as bottom-field-first.
๐ Examples
- Interlace video using
selectandseparatefieldsfilter:
separatefields,select=eq(mod(n,4),0)+eq(mod(n,4),3),weave
๐ xbr
Apply the xBR high-quality magnification filter which is designed for pixel art. It follows a set of edge-detection rules, see <https://forums.libretro.com/t/xbr-algorithm-tutorial/123> โ pixel art girlies stay winning ๐ฎโจ
It accepts the following option:
nโ Set the scaling dimension:2for"2xBR",3for"3xBR"and4for"4xBR". Default is3.
๐งฎ xcorrelate
Apply normalized cross-correlation between first and second input video stream.
Second input video stream dimensions must be lower than first input video stream โ no exceptions, bestie, that's the vibe check โ ๏ธ
The filter accepts the following options:
planesโ Set which planes to process.secondaryโ Set which secondary video frames will be processed from second input video stream, can befirstorall. Default isall.
The "xcorrelate" filter also supports the framesync options โ free real estate, we love to see it ๐ซถ
๐ฌ xfade
Apply cross fade from one input video stream to another input video stream. The cross fade is applied for specified duration โ smooth transition hours ๐ธ
Both inputs must be constant frame-rate and have the same resolution, pixel format, frame rate and timebase. All matching, periodt.
The filter accepts the following options:
transitionโ Set one of available transition effects:
okay so the transition names you can pick from are literally a whole menu โ no cap, hereโs the full lineup:
custom
fade
wipeleft
wiperight
wipeup
wipedown
slideleft
slideright
slideup
slidedown
circlecrop
rectcrop
distance
fadeblack
fadewhite
radial
smoothleft
smoothright
smoothup
smoothdown
circleopen
circleclose
vertopen
vertclose
horzopen
horzclose
dissolve
pixelize
diagtl
diagtr
diagbl
diagbr
hlslice
hrslice
vuslice
vdslice
hblur
fadegrays
wipetl
wipetr
wipebl
wipebr
squeezeh
squeezev
zoomin
fadefast
fadeslow
hlwind
hrwind
vuwind
vdwind
coverleft
coverright
coverup
coverdown
revealleft
revealright
revealup
revealdown
Default transition effect is fade โ sheโs the default for a reason ๐
durationโ sets cross fade duration in seconds. Range is 0 to 60 seconds. Default duration is 1 second.offsetโ sets cross fade start relative to first input stream in seconds. Default offset is 0.exprโ sets expression for custom transition effect.
The expressions can use these variables and functions, bestie:
X,Yโ the coordinates of the current sample.W,Hโ the width and height of the image.Pโ progress of transition effect.PLANEโ currently processed plane.Aโ return value of first input at current location and plane.Bโ return value of second input at current location and plane.a0(x, y),a1(x, y),a2(x, y),a3(x, y)โ return the value of the pixel at location(x,y)of the first/second/third/fourth component of first input.b0(x, y),b1(x, y),b2(x, y),b3(x, y)โ return the value of the pixel at location(x,y)of the first/second/third/fourth component of second input.
Examples
- Cross fade from one input video to another input video, with
fadetransition and duration of transition of 2 seconds starting at offset of 5 seconds:
ffmpeg -i first.mp4 -i second.mp4 -filter_complex xfade=transition=fade:duration=2:offset=5 output.mp4
xmedian
Pick median pixels from several input videos โ itโs giving group project, but make it median โจ
The filter accepts the following options:
inputsโ set number of inputs. Default is 3. Allowed range is from 3 to 255. If number of inputs is even number, then result will be mean value between two median values.planesโ set which planes to filter. Default value is 15, by which all planes are processed.percentileโ set median percentile. Default value is 0.5. Default value of 0.5 will pick always median values, while 0 will pick minimum values, and 1 maximum values.
Commands
This filter supports all above options as commands, excluding option "inputs".
xpsnr
Obtain the average (across all input frames) and minimum (across all color plane averages) eXtended Perceptually weighted peak Signal-to-Noise Ratio (XPSNR) between two input videos. iconic metric behavior ๐ฅ
The XPSNR is a low-complexity psychovisually motivated distortion measurement algorithm for assessing the difference between two video streams or images. This is especially useful for objectively quantifying the distortions caused by video and image codecs, as an alternative to a formal subjective test. The logarithmic XPSNR output values are in a similar range as those of traditional psnr assessments but better reflect human impressions of visual coding quality. More details on the XPSNR measure, which essentially represents a blockwise weighted variant of the PSNR measure, can be found in the following freely available papers:
- C. R. Helmrich, M. Siekmann, S. Becker, S. Bosse, D. Marpe, and T. Wiegand, "XPSNR: A Low-Complexity Extension of the Perceptually Weighted Peak Signal-to-Noise Ratio for High-Resolution Video Quality Assessment," in Proc. IEEE Int. Conf. Acoustics, Speech, Sig. Process. (ICASSP), virt./online, May 2020.
www.ecodis.de/xpsnr.htm - C. R. Helmrich, S. Bosse, H. Schwarz, D. Marpe, and T. Wiegand, "A Study of the Extended Perceptually Weighted Peak Signal-to-Noise Ratio (XPSNR) for Video Compression with Different Resolutions and Bit Depths," ITU Journal: ICT Discoveries, vol. 3, no. 1, pp. 65 - 72, May 2020.
http://handle.itu.int/11.1002/pub/8153d78b-en
When publishing the results of XPSNR assessments obtained using, e.g., this FFmpeg filter, a reference to the above papers as a means of documentation is strongly encouraged. The filter requires two input videos. The first input is considered a (usually not distorted) reference source and is passed unchanged to the output, whereas the second input is a (distorted) test signal. Except for the bit depth, these two video inputs must have the same pixel format. In addition, for best performance, both compared input videos should be in YCbCr color format.
The obtained overall XPSNR values mentioned above are printed through the logging system. In case of input with multiple color planes, we suggest reporting of the minimum XPSNR average.
The following parameter, which behaves like the one for the psnr filter, is accepted:
stats_file,fโ if specified, the filter will use the named file to save the XPSNR value of each individual frame and color plane. When the file name equals"-", that data is sent to standard output.
This filter also supports the framesync options.
Examples
- XPSNR analysis of two 1080p HD videos,
ref_source.yuvandtest_video.yuv, both at 24 frames per second, with color format 4:2:0, bit depth 8, and output of a logfile named"xpsnr.log":
ffmpeg -s 1920x1080 -framerate 24 -pix_fmt yuv420p -i ref_source.yuv -s 1920x1080 -framerate 24 -pix_fmt yuv420p -i test_video.yuv -lavfi xpsnr="stats_file=xpsnr.log" -f null -
- XPSNR analysis of two 2160p UHD videos,
ref_source.yuvwith bit depth 8 andtest_video.yuvwith bit depth 10, both at 60 frames per second with color format 4:2:0, no logfile output:
ffmpeg -s 3840x2160 -framerate 60 -pix_fmt yuv420p -i ref_source.yuv -s 3840x2160 -framerate 60 -pix_fmt yuv420p10le -i test_video.yuv -lavfi xpsnr="stats_file=-" -f null -
xstack
Stack video inputs into custom layout. All streams must be of same pixel format. pixel format matching is mandatory, bestie โ no mixing and matching ๐ซถ
The filter accepts the following options:
inputsโ set number of input streams. Default is 2.layoutโ specify layout of inputs. This option requires the desired layout configuration to be explicitly set by the user. This sets position of each video input in output. Each input is separated by'|'. The first number represents the column, and the second number represents the row. Numbers start at 0 and are separated by'_'. Optionally one can usewXandhX, whereXis video input from which to take width or height. Multiple values can be used when separated by'+'. In such case values are summed together.
Note that if inputs are of different sizes gaps may appear, as not all of the output video frame will be filled. Similarly, videos can overlap each other if their position doesn't leave enough space for the full frame of adjoining videos.
For 2 inputs, a default layout of "0_0|w0_0" (equivalent to "grid=2x1") is set. In all other cases, a layout or a grid must be set by the user. Either "grid" or "layout" can be specified at a time. Specifying both will result in an error.
gridโ specify a fixed size grid of inputs. This option is used to create a fixed size grid of the input streams. Set the grid size in the form"COLUMNSxROWS". There must be"ROWS * COLUMNS"input streams and they will be arranged as a grid with"ROWS"rows and"COLUMNS"columns. When using this option, each input stream within a row must have the same height and all the rows must have the same width.
If "grid" is set, then "inputs" option is ignored and is implicitly set to "ROWS * COLUMNS".
For 2 inputs, a default grid of "2x1" (equivalent to "layout=0_0|w0_0") is set. In all other cases, a layout or a grid must be set by the user. Either "grid" or "layout" can be specified at a time. Specifying both will result in an error.
shortestโ if set to 1, force the output to terminate when the shortest input terminates. Default value is 0.fillโ if set to valid color, all unused pixels will be filled with that color. By default fill is set to none, so it is disabled.
Examples
- Display 4 inputs into 2x2 grid.
Layout:
input1(0, 0) | input3(w0, 0)
input2(0, h0) | input4(w0, h0)
xstack=inputs=4:layout=0_0|0_h0|w0_0|w0_h0
Note that if inputs are of different sizes, gaps or overlaps may occur.
- Display 4 inputs into 1x4 grid.
Layout:
input1(0, 0)
input2(0, h0)
input3(0, h0+h1)
input4(0, h0+h1+h2)
xstack=inputs=4:layout=0_0|0_h0|0_h0+h1|0_h0+h1+h2
Note that if inputs are of different widths, unused space will appear.
- Display 9 inputs into 3x3 grid.
Layout:
input1(0, 0) | input4(w0, 0) | input7(w0+w3, 0)
input2(0, h0) | input5(w0, h0) | input8(w0+w3, h0)
input3(0, h0+h1) | input6(w0, h0+h1) | input9(w0+w3, h0+h1)
xstack=inputs=9:layout=0_0|0_h0|0_h0+h1|w0_0|w0_h0|w0_h0+h1|w0+w3_0|w0+w3_h0|w0+w3_h0+h1
Note that if inputs are of different sizes, gaps or overlaps may occur.
- Display 16 inputs into 4x4 grid.
Layout:
input1(0, 0) | input5(w0, 0) | input9 (w0+w4, 0) | input13(w0+w4+w8, 0)
input2(0, h0) | input6(w0, h0) | input10(w0+w4, h0) | input14(w0+w4+w8, h0)
input3(0, h0+h1) | input7(w0, h0+h1) | input11(w0+w4, h0+h1) | input15(w0+w4+w8, h0+h1)
input4(0, h0+h1+h2)| input8(w0, h0+h1+h2)| input12(w0+w4, h0+h1+h2)| input16(w0+w4+w8, h0+h1+h2)
xstack=inputs=16:layout=0_0|0_h0|0_h0+h1|0_h0+h1+h2|w0_0|w0_h0|w0_h0+h1|w0_h0+h1+h2|w0+w4_0|w0+w4_h0|w0+w4_h0+h1|w0+w4_h0+h1+h2|w0+w4+w8_0|w0+w4+w8_h0|w0+w4+w8_h0+h1|w0+w4+w8_h0+h1+h2
No cap: if the inputs are different sizes, you might get gaps or overlaps. Just so you know ๐
yadif
Deinterlaces your video, bestie โ and yeah, yadif stands for "yet another deinterlacing filter" ๐ญ the devs really said "we've done this before" and did it again, and honestly? Iconic.
It takes these parameters:
modeโ the interlacing mode to adopt. It accepts one of these values:0, send_frameโ output one frame for each frame.1, send_fieldโ output one frame for each field.2, send_frame_nospatialโ likesend_frame, but it skips the spatial interlacing check ๐3, send_field_nospatialโ likesend_field, but it skips the spatial interlacing check ๐
The default value is send_frame.
parityโ the picture field parity assumed for the input interlaced video. It accepts one of these values:0, tffโ assume the top field is first.1, bffโ assume the bottom field is first.-1, autoโ enable automatic detection of field parity.
The default value is auto. If the interlacing is unknown or the decoder doesn't export this info, top field first will be assumed. (So it just assumes, and we love a confident filter ๐ซถ)
deintโ specify which frames to deinterlace. Accepts one of these values:0, allโ deinterlace all frames.1, interlacedโ only deinterlace frames marked as interlaced.
The default value is all.
yaepblur
Blur filter that preserves edges โ yaepblur means "yet another edge preserving blur filter" ๐ these names, I swear. The algorithm is described in "J. S. Lee, Digital image enhancement and noise filtering by use of local statistics, IEEE Trans. Pattern Anal. Mach. Intell. PAMI-2, 1980." โ yes, actual academic citation, we stan a well-read filter ๐
It accepts these parameters:
radius,rโ set the window radius. Default value is3.planes,pโ set which planes to filter. Default is only the first plane.sigma,sโ set blur strength. Default value is128.
Commands
This filter supports the same commands as options. Slay โจ
zoompan
Applies the Zoom & Pan effect. Main character energy, literally moving the camera around your frame ๐ฅ
This filter accepts the following options:
zoom,zโ set the zoom expression. Range is1-10. Default is1.x,yโ set thexandyexpression. Default is0.dโ set the duration expression in number of frames. This sets for how many frames the effect will last for a single input image. Default is90.sโ set the output image size, default ishd720.fpsโ set the output frame rate, default is25.
Each expression can contain the following constants:
in_w,iwโ input width.in_h,ihโ input height.out_w,owโ output width.out_h,ohโ output height.inโ input frame count.onโ output frame count.in_time,itโ the input timestamp expressed in seconds. It'sNANif the input timestamp is unknown. (iykyk,NANmeans "no thoughts head empty" here ๐)out_time,time,otโ the output timestamp expressed in seconds.x,yโ last calculatedxandyposition from thexandyexpression for the current input frame.px,pyโxandyof the last output frame of the previous input frame, or0when there wasn't such a frame yet (first input frame).zoomโ last calculated zoom from thezexpression for the current input frame.pzoomโ last calculated zoom of the last output frame of the previous input frame.durationโ number of output frames for the current input frame. Calculated from thedexpression for each input frame.pdurationโ number of output frames created for the previous input frame.aโ rational number: input width / input height.sarโ sample aspect ratio.darโ display aspect ratio.
Examples
- Zoom in up to 1.5x and pan at the same time to some spot near the center of the picture:
zoompan=z='min(zoom+0.0015,1.5)':d=700:x='if(gte(zoom,1.5),x,x+1/a)':y='if(gte(zoom,1.5),y,y+1)':s=640x360
- Zoom in up to 1.5x and pan always at the center of the picture:
zoompan=z='min(zoom+0.0015,1.5)':d=700:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)'
- Same as above but without pausing:
zoompan=z='min(max(zoom,pzoom)+0.0015,1.5)':d=1:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)'
- Zoom in 2x into the center of the picture only for the first second of the input video:
zoompan=z='if(between(in_time,0,1),2,1)':d=1:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)'
zscale
Scales (resizes) the input video using the z.lib library: <https://github.com/sekrit-twc/zimg>. To enable compilation of this filter, you need to configure FFmpeg with --enable-libzimg ๐ ๏ธ
The zscale filter forces the output display aspect ratio to be the same as the input, by changing the output sample aspect ratio. Sneaky but correct ๐
If the input image format is different from the format requested by the next filter, the zscale filter will convert the input to the requested format.
Options
The filter accepts the following options.
width,w,height,hโ set the output video dimension expression. Default value is the input dimension.
If the width or w value is 0, the input width is used for the output. If the height or h value is 0, the input height is used for the output.
If one and only one of the values is -n with n >= 1, the zscale filter will use a value that maintains the aspect ratio of the input image, calculated from the other specified dimension. After that it will, however, make sure that the calculated dimension is divisible by n and adjust the value if necessary.
If both values are -n with n >= 1, the behavior will be identical to both values being set to 0 as previously detailed.
See below for the list of accepted constants for use in the dimension expression.
size,sโ set the video size. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual.dither,dโ set the dither type. Possible values are:noneorderedrandomerror_diffusion
Default is none.
filter,fโ set the resize filter type. Possible values are:pointbilinearbicubicspline16spline36spline64lanczos
Default is bilinear.
range,rโ set the color range. Possible values are:inputlimitedfull
Default is same as input.
primaries,pโ set the color primaries. Possible values are:input709unspecified170m240m2020
Default is same as input.
transfer,tโ set the transfer characteristics. Possible values are:input709unspecified601linear2020_102020_12smpte2084iec61966-2-1arib-std-b67
Default is same as input.
matrix,mโ set the colorspace matrix. Possible value are:input709unspecified470bg170m2020_ncl2020_cl
Default is same as input.
rangein,rinโ set the input color range. Possible values are:inputlimitedfull
Default is same as input.
primariesin,pinโ set the input color primaries. Possible values are:input709unspecified170m240m2020
Default is same as input.
transferin,tinโ set the input transfer characteristics. Possible values are:input709unspecified601linear2020_102020_12
Default is same as input.
matrixin,minโ set the input colorspace matrix. Possible value are:input709unspecified470bg170m2020_ncl2020_cl
chromal,cโ set the output chroma location. Possible values are:inputleftcentertoplefttopbottomleftbottom
chromalin,cinโ set the input chroma location. Possible values are:inputleftcentertoplefttopbottomleftbottom
nplโ set the nominal peak luminance.param_aโ parameter A for scaling filters. Parameterbfor bicubic, and the number of filter taps for lanczos.param_bโ parameter B for scaling filters. Parametercfor bicubic.
The values of the w and h options are expressions containing the following constants:
in_w,in_hโ the input width and height.iw,ihโ these are the same asin_wandin_h.out_w,out_hโ the output (scaled) width and height.ow,ohโ these are the same asout_wandout_h.aโ the same asiw / ih.sarโ input sample aspect ratio.darโ the input display aspect ratio. Calculated from(iw / ih) * sar.hsub,vsubโ horizontal and vertical input chroma subsample values. For example for the pixel formatyuv422p,hsubis2andvsubis1.ohsub,ovsubโ horizontal and vertical output chroma subsample values. For example for the pixel formatyuv422p,hsubis2andvsubis1.
Commands
This filter supports the following commands:
width,w,height,hโ set the output video dimension expression. The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current value. (No crash, no drama, it just stays where it is ๐ง)
๐ฆ CUDA VIDEO FILTERS ๐ฆ
To enable CUDA and/or NPP filters, please refer to the configuration guidelines for CUDA and for CUDA NPP filters. Lowkey a whole setup quest, but we move ๐ซถ
Running CUDA filters requires you to initialize a hardware device and to pass that device to all filters in any filter graph. Non-negotiable, bestie.
-init_hw_device cuda[=name][:device[,key=value...]]โ initialise a new hardware device of typecudacalled name, using the given device parameters.-filter_hw_device nameโ pass the hardware device called name to all filters in any filter graph.
For more detailed information see <https://www.ffmpeg.org/ffmpeg.html#Advanced-Video-options>
- Example of initializing a second CUDA device on the system and running
scale_cudaandbilateral_cudafilters.
./ffmpeg -hwaccel cuda -hwaccel_output_format cuda -i input.mp4 -init_hw_device cuda:1 -filter_complex \
"[0:v]scale_cuda=format=yuv444p[scaled_video];[scaled_video]bilateral_cuda=window_size=9:sigmaS=3.0:sigmaR=50.0" \
-an -sn -c:v h264_nvenc -cq 20 out.mp4
So like, CUDA filters live and breathe exclusively on GPU memory, which means frame data sometimes has to get uploaded (hwupload) to hardware surfaces tied to the right CUDA device before processing, and then downloaded (hwdownload) back to regular memory afterward if you need it there. Whether hwupload or hwdownload is actually necessary is giving "depends on your workflow" energy:
- If the input frames are already in GPU memory (like, say, when you're using
-hwaccel cudaor-hwaccel_output_format cuda), you do not need to explicitly usehwuploadโ the data is already chilling in the appropriate memory space. Slay. ๐ - If the input frames are in CPU memory (software-decoded frames, or frames that got processed by CPU-based filters), then yeah, you do need
hwuploadto transfer that data over to GPU memory so CUDA processing can happen. - If the output of the CUDA filters needs more processing by software-based filters, or needs to be saved in a format the GPU-based encoders don't support, then
hwdownloadis required to haul the data back to CPU memory.
Heads up bestie ๐ซถ โhwuploaduploads data to a surface with the same layout as the software frame, so you may need to drop aformatfilter immediately beforehwuploadto make sure the input is in the correct format. Same vibe in reverse:hwdownloadmay not support all output formats, so an extraformatfilter might need to be slipped in immediately afterhwdownloadin the filter graph to keep everything compatible.
CUDA
Here's the rundown on the currently available Nvidia CUDA video filters, bestie โจ
Prerequisites:
- Install Nvidia CUDA Toolkit
Note: if FFmpeg detects the Nvidia CUDA Toolkit during configuration, it will enable CUDA filters automatically, no extra flags needed. But if you want to explicitly enable them, use these options:
- Configure FFmpeg with
--enable-cuda-nvcc --enable-nonfree. - Configure FFmpeg with
--enable-cuda-llvm. Bonus requirement: thellvmlib must be installed.
bilateral_cuda
CUDA accelerated bilateral filter โ an edge preserving filter, and it's mathematically accurate thanks to that GPU acceleration, no cap ๐ฅ For the best output quality, use one to one chroma subsampling, i.e. yuv444p format.
The filter accepts the following options:
sigmaSโ Sets the sigma of the gaussian function used to calculate the spatial weight, also called sigma space. Allowed range is0.1to512. Default is0.1.sigmaRโ Sets the sigma of the gaussian function used to calculate the color range weight, also called sigma color. Allowed range is0.1to512. Default is0.1.window_sizeโ Sets the window size of the bilateral function to determine how many neighbours to loop on. If the number you enter is even, one will be added automatically (sneaky lil auto-correct ๐). Allowed range is1to255. Default is1.
Examples
- Apply the bilateral filter on a video.
./ffmpeg -v verbose \
-hwaccel cuda -hwaccel_output_format cuda -i input.mp4 \
-init_hw_device cuda \
-filter_complex \
" \
[0:v]scale_cuda=format=yuv444p[scaled_video];
[scaled_video]bilateral_cuda=window_size=9:sigmaS=3.0:sigmaR=50.0" \
-an -sn -c:v h264_nvenc -cq 20 out.mp4
bwdif_cuda
Deinterlaces the input video using the bwdif algorithm, but implemented in CUDA so it can run as part of a GPU accelerated pipeline with nvdec and/or nvenc. Iconic teamwork honestly ๐
It accepts the following parameters:
modeโ The interlacing mode to adopt. Accepts one of the following values:0,send_frameโ Output one frame for each frame.1,send_fieldโ Output one frame for each field.
The default value is send_field.
parityโ The picture field parity assumed for the input interlaced video. Accepts one of the following values:0,tffโ Assume the top field is first.1,bffโ Assume the bottom field is first.-1,autoโ Enable automatic detection of field parity.
The default value is auto. If the interlacing is unknown or the decoder doesn't export this information, top field first will be assumed.
deintโ Specifies which frames to deinterlace. Accepts one of the following values:0,allโ Deinterlace all frames.1,interlacedโ Only deinterlace frames marked as interlaced.
The default value is all.
chromakey_cuda
CUDA accelerated YUV colorspace color/chroma keying ๐
This filter works like the normal chromakey filter but operates on CUDA frames. For more details and parameters see chromakey.
Examples
- Make all the green pixels in the input video transparent and use it as an overlay for another video:
./ffmpeg \
-hwaccel cuda -hwaccel_output_format cuda -i input_green.mp4 \
-hwaccel cuda -hwaccel_output_format cuda -i base_video.mp4 \
-init_hw_device cuda \
-filter_complex \
" \
[0:v]chromakey_cuda=0x25302D:0.1:0.12:1[overlay_video]; \
[1:v]scale_cuda=format=yuv420p[base]; \
[base][overlay_video]overlay_cuda" \
-an -sn -c:v h264_nvenc -cq 20 output.mp4
- Process two software sources, explicitly uploading the frames:
./ffmpeg -init_hw_device cuda=cuda -filter_hw_device cuda \
-f lavfi -i color=size=800x600:color=white,format=yuv420p \
-f lavfi -i yuvtestsrc=size=200x200,format=yuv420p \
-filter_complex \
" \
[0]hwupload[under]; \
[1]hwupload,chromakey_cuda=green:0.1:0.12[over]; \
[under][over]overlay_cuda" \
-c:v hevc_nvenc -cq 18 -preset slow output.mp4
colorspace_cuda
CUDA accelerated implementation of the colorspace filter.
Real talk: it is by no means feature complete compared to the software colorspace filter โ at the current time it only supports color range conversion between jpeg/full and mpeg/limited range. That's it, that's the whole menu ๐ญ
The filter accepts the following options:
rangeโ Specify output color range. The accepted values are:tvโ TV (restricted) rangempegโ MPEG (restricted) rangepcโ PC (full) rangejpegโ JPEG (full) range
overlay_cuda
Overlay one video on top of another. Classic main character move โจ
This is the CUDA variant of the overlay filter. It only accepts CUDA frames. The underlying input pixel formats have to match.
It takes two inputs and has one output. The first input is the main video, and the second input gets overlaid on top of it.
It accepts the following parameters:
x,yโ Set expressions for the x and y coordinates of the overlaid video on the main video.
They can contain the following parameters:
main_w,Wโ The main input width and height.main_h,Hโ The main input width and height.overlay_w,wโ The overlay input width and height.overlay_h,hโ The overlay input width and height.x,yโ The computed values forxandy. They are evaluated for each new frame.nโ The ordinal index of the main input frame, starting from0.posโ The byte offset position in the file of the main input frame,NANif unknown. Deprecated, do not use. ๐ซtโ The timestamp of the main input frame, expressed in seconds,NANif unknown.
Default value is 0 for both expressions.
evalโ Set when the expressions forxandyare evaluated. It accepts the following values:initโ Evaluate expressions once during filter initialization or when a command is processed.frameโ Evaluate expressions for each incoming frame
Default value is frame.
eof_actionโ Seeframesync.shortestโ Seeframesync.repeatlastโ Seeframesync.
This filter also supports the framesync options.
pad_cuda
Add paddings to an input video stream using CUDA ๐
This filter is the CUDA-accelerated version of the pad filter. It accepts the same options and expressions and provides the same core functionality. For a detailed description of the available options, please see the documentation for the pad filter.
Examples
- Add a 200-pixel black border to all sides of a video frame:
ffmpeg -hwaccel cuda -hwaccel_output_format cuda -i input.mp4 -vf "pad_cuda=w=iw+400:h=ih+400:x=200:y=200" -c:v h264_nvenc out.mp4
- Pad the input video to a 16:9 aspect ratio, filling with the color
blue:
ffmpeg -hwaccel cuda -hwaccel_output_format cuda -i input.mp4 -vf "pad_cuda=w=ih*16/9/sar:h=ih:x=(ow-iw)/2:y=(oh-ih)/2:color=blue" -c:v h264_nvenc out.mp4
scale_cuda
Scale (resize) and convert (pixel format) the input video, using accelerated CUDA kernels ๐ Setting the output width and height works in the same way as for the scale filter.
The filter accepts the following options:
w,hโ Set the output video dimension expression. Default value is the input dimension.
Allows for the same expressions as the scale filter.
interp_algoโ Sets the algorithm used for scaling:nearestโ Nearest neighbour
Used by default if input parameters match the desired output.
bilinearโ Bilinearbicubicโ Bicubic
This is the default.
lanczosโ Lanczos
formatโ Controls the output pixel format. By default, or if none is specified, the input pixel format is used.
The filter does not support converting between YUV and RGB pixel formats. (sorry babes ๐)
passthroughโ If set to0, every frame is processed, even if no conversion is necessary. This mode can be useful to use the filter as a buffer for a downstream frame-consumer that exhausts the limited decoder frame pool.
If set to 1, frames are passed through as-is if they match the desired output parameters. This is the default behaviour.
use_filtersโ If set to1, filter with a generic weight LUT instead of using fixed-function shader kernels. May be faster or slower depending on the hardware. A value ofauto(the default) enables this automatically when required for correct anti-aliasing when downscaling.paramโ Algorithm-Specific parameter.
Affects the curves of the bicubic algorithm.
force_original_aspect_ratio,force_divisible_byโ Work the same as the identicalscalefilter options.reset_sarโ Works the same as the identicalscalefilter option.
Examples
- Scale input to 720p, keeping the aspect ratio and making sure the output is
yuv420p. Obsessed with how clean this one is:
scale_cuda=-2:720:format=yuv420p
- Upscale to 4K using the nearest neighbour algorithm. Big pixel energy, no smoothing, no thoughts:
scale_cuda=4096:2160:interp_algo=nearest
- Don't convert or scale anything at all โ just copy every input frame into a freshly allocated one. Sounds pointless, but it's actually a slay: it's useful when your filter + encode chain would otherwise exhaust the decoder's frame pool ๐
scale_cuda=passthrough=0
thumbnail_cuda
Picks the most representative frame out of a whole sequence of consecutive frames, and it does it with CUDA so it's fast. Basically the filter is scrolling through your timeline going "this one. this is the moment." ๐
It accepts these options:
nโ sets how many frames go in each batch to analyze. In a set ofnframes, the filter picks one of them, then moves on to the next batch ofnframes and keeps doing that till the end. Default is100.
Fr fr, since this filter keeps track of the whole frames sequence, a bigger n value means higher memory usage. So like... don't go wild with a huge value, bestie ๐ญ
Example
- Thumbnails get extracted from every
n=150-frame batch, one per batch. Then the chosen frames get scaled withscale_cuda:
./ffmpeg -hwaccel cuda -hwaccel_output_format cuda -i ./input.mp4 -vf "thumbnail_cuda=150,scale_cuda=1920:1080,hwdownload,format=nv12" ./output/out%03d.png
yadif_cuda
Deinterlaces the input video using the yadif algorithm โ but implemented in CUDA, so it can be part of a fully GPU-accelerated pipeline with nvdec and/or nvenc. It's giving teamwork, it's giving efficiency ๐ซถ
It accepts the following parameters:
modeโ the interlacing mode to adopt. Takes one of these values:0,send_frameโ outputs one frame for each frame.1,send_fieldโ outputs one frame for each field.2,send_frame_nospatialโ likesend_frame, but it skips the spatial interlacing check.3,send_field_nospatialโ likesend_field, but it skips the spatial interlacing check.
The default value is send_frame.
parityโ the picture field parity assumed for the input interlaced video. Takes one of these values:0,tffโ assumes the top field is first.1,bffโ assumes the bottom field is first.-1,autoโ enables automatic detection of field parity.
The default value is auto. And heads up: if the interlacing is unknown or the decoder doesn't export this info, top field first will be assumed.
deintโ specifies which frames to deinterlace. Accepts one of these values:0,allโ deinterlaces all frames.1,interlacedโ only deinterlaces frames marked as interlaced.
The default value is all.
๐ CUDA NPP ๐
Okay so below here is a description of the currently available NVIDIA Performance Primitives (libnpp) video filters โจ
Prerequisites:
- Install Nvidia CUDA Toolkit
- Install libnpp
To enable CUDA NPP filters:
- Configure FFmpeg with
--enable-nonfree --enable-libnpp.
scale_npp
Uses the NVIDIA Performance Primitives (libnpp) to do scaling and/or pixel format conversion on CUDA video frames. Setting the output width and height works exactly the same way as it does for the scale filter. Same vibes, GPU edition ๐
These additional options are accepted:
formatโ the pixel format of the output CUDA frames. If you set it to the stringsame(which is the default), the input format gets kept. Note that automatic format negotiation and conversion is not yet supported for hardware frames.interp_algoโ the interpolation algorithm used for resizing. One of the following:nnโ nearest neighbour.linearcubiccubic2p_bsplineโ 2-parameter cubic (B=1, C=0)cubic2p_catmullromโ 2-parameter cubic (B=0, C=1/2)cubic2p_b05c03โ 2-parameter cubic (B=1/2, C=3/10)superโ supersamplinglanczos
force_original_aspect_ratioโ lets you decrease or increase the output video width or height when necessary to keep the original aspect ratio. Possible values:disableโ scales the video as specified and disables this feature.decreaseโ the output video dimensions will automatically be decreased if needed.increaseโ the output video dimensions will automatically be increased if needed.
One genuinely useful instance of this option: when you know a specific device's maximum allowed resolution, you can use this to limit the output video to that while keeping the aspect ratio. For example, device A allows 1280x720 playback, and your video is 1920x800. Using this option (set it to decrease) and specifying 1280x720 on the command line makes the output 1280x533. Math ate, honestly ๐ฅ
Please note this is a different thing than specifying-1forworhโ you still need to specify the output resolution for this option to work.
force_divisible_byโ ensures that both output dimensions, width and height, are divisible by the given integer when used together withforce_original_aspect_ratio. Works similar to using-nin thewandhoptions.
This option respects the value set for force_original_aspect_ratio, increasing or decreasing the resolution accordingly. Warning though: the video's aspect ratio may be slightly modified ๐ฌ
It's handy if you need a video to fit within or exceed a defined resolution using force_original_aspect_ratio but you also have encoder restrictions on width or height divisibility.
reset_sarโ works the same as the identicalscalefilter option.evalโ specifies when to evaluate the width and height expression. It accepts the following values:initโ only evaluate expressions once during the filter initialization or when a command is processed.frameโ evaluate expressions for each incoming frame.
The values of the w and h options are expressions containing the following constants:
in_w,in_hโ the input width and height.iw,ihโ these are the same asin_wandin_h.out_w,out_hโ the output (scaled) width and height.ow,ohโ these are the same asout_wandout_h.aโ the same asiw / ih.sarโ input sample aspect ratio.darโ the input display aspect ratio. Calculated from(iw / ih) * sar.nโ the (sequential) number of the input frame, starting from 0. Only available witheval=frame.tโ the presentation timestamp of the input frame, expressed as a number of seconds. Only available witheval=frame.posโ the position (byte offset) of the frame in the input stream, orNaNif this information is unavailable and/or meaningless (for example in case of synthetic video). Only available witheval=frame. Deprecated, do not use ๐ซ
scale2ref_npp
Uses the NVIDIA Performance Primitives (libnpp) to scale (resize) the input video, based on a reference video. It's literally the main character scaling itself to match its fave ๐ซถ
See the scale_npp filter for the available options โ scale2ref_npp supports the same ones, but it uses the reference video instead of the main input as its basis. scale2ref_npp also supports these additional constants for the w and h options:
main_w,main_hโ the main input video's width and height.main_aโ the same asmain_w / main_h.main_sarโ the main input video's sample aspect ratio.main_dar,mdarโ the main input video's display aspect ratio. Calculated from(main_w / main_h) * main_sar.main_nโ the (sequential) number of the main input frame, starting from 0. Only available witheval=frame.main_tโ the presentation timestamp of the main input frame, expressed as a number of seconds. Only available witheval=frame.main_posโ the position (byte offset) of the frame in the main input stream, orNaNif this information is unavailable and/or meaningless (for example in case of synthetic video). Only available witheval=frame.
Examples
- Scale a subtitle stream (
b) to match the main video (a) in size before overlaying:
'scale2ref_npp[b][a];[a][b]overlay_cuda'
- Scale a logo to 1/10th the height of a video, while preserving its display aspect ratio:
[logo-in][video-in]scale2ref_npp=w=oh*mdar:h=ih/10[logo-out][video-out]
sharpen_npp
Uses the NVIDIA Performance Primitives (libnpp) to perform image sharpening with border control. Crispy edges, no cap โจ
These additional options are accepted:
border_typeโ the type of sampling to be used at frame borders. One of the following:replicateโ replicate pixel values.
transpose_npp
Transposes rows with columns in the input video and optionally flips it. For more in-depth examples, see the transpose video filter, which shares mostly the same options. Flip era ๐
It accepts the following parameters:
dirโ specifies the transposition direction.
Can assume the following values:
cclock_flipโ rotate by 90 degrees counterclockwise and vertically flip. (default)clockโ rotate by 90 degrees clockwise.cclockโ rotate by 90 degrees counterclockwise.clock_flipโ rotate by 90 degrees clockwise and vertically flip.
passthroughโ doesn't apply the transposition if the input geometry matches the one specified by the given value. Accepts the following values:noneโ always apply transposition. (default)portraitโ preserve portrait geometry (whenheight >= width).landscapeโ preserve landscape geometry (whenwidth >= height).
๐ OPENCL VIDEO FILTERS ๐
Below is a description of the currently available OpenCL video filters. GPU girlies rise ๐ฆ
To enable compilation of these filters you need to configure FFmpeg with --enable-opencl.
Running OpenCL filters means you've gotta initialize a hardware device and pass that device to all filters in any filter graph. It's giving "no device left behind" ๐
-init_hw_device opencl[=name][:device[,key=value...]]โ initialises a new hardware device of typeopenclcalled name, using the given device parameters.-filter_hw_device nameโ passes the hardware device called name to all filters in any filter graph.
For more detailed information, see <https://www.ffmpeg.org/ffmpeg.html#Advanced-Video-options>
- Example of choosing the first device on the second platform and running the
avgblur_openclfilter with default parameters on it:
-init_hw_device opencl=gpu:1.0 -filter_hw_device gpu -i INPUT -vf "hwupload, avgblur_opencl, hwdownload" OUTPUT
okay so real talk bestie โ OpenCL filters literally cannot reach frame data while it's just chilling in normal memory ๐ญ so every single frame has to be uploaded first with hwupload onto hardware surfaces that are connected to the appropriate device, used, and then downloaded back into normal memory with hwdownload.
โ ๏ธ heads up:hwuploaduploads to a surface with the same layout as the software frame, so you may need to add aformatfilter immediately before it to get the input into the right format ๐ andhwdownloaddoes not support all formats on the output โ it may be necessary to insert an additionalformatfilter immediately following it in the graph to get the output into a supported format. no cap, plan your graph accordingly ๐ซถ
๐ avgblur_opencl
Apply that average blur filter, bestie โจ
The filter accepts the following options:
sizeXโ sets the horizontal radius size. Range is[1, 1024]and the default value is1.planesโ picks which planes get filtered. Default value is0xf, which means all planes are processed ๐sizeYโ sets the vertical radius size. Range is[1, 1024]and the default value is0. If it's zero, thesizeXvalue gets used instead.
Example
- Apply average blur filter with horizontal and vertical size of
3, setting each pixel of the output to the average value of the 7x7 region centered on it in the input. For pixels on the edges of the image, the region does not extend beyond the image boundaries, and so out-of-range coordinates are not used in the calculations.
-i INPUT -vf "hwupload, avgblur_opencl=3, hwdownload" OUTPUT
๐ง boxblur_opencl
Applies a boxblur algorithm to the input video ๐ฆ
It accepts the following parameters:
luma_radius,lrluma_power,lpchroma_radius,crchroma_power,cpalpha_radius,aralpha_power,ap
A description of the accepted options follows ๐
luma_radius, lr / chroma_radius, cr / alpha_radius, ar
Set an expression for the box radius in pixels used for blurring the corresponding input plane.
The radius value must be a non-negative number, and must not be greater than the value of the expression min(w,h)/2 for the luma and alpha planes, and of min(cw,ch)/2 for the chroma planes ๐
Default value for luma_radius is 2. If not specified, chroma_radius and alpha_radius default to the corresponding value set for luma_radius.
The expressions can contain the following constants:
w,hโ the input width and height in pixels.cw,chโ the input chroma image width and height in pixels.hsub,vsubโ the horizontal and vertical chroma subsample values. For example, for the pixel formatyuv422p,hsubis 2 andvsubis 1.
luma_power, lp / chroma_power, cp / alpha_power, ap
Specify how many times the boxblur filter is applied to the corresponding plane.
Default value for luma_power is 2. If not specified, chroma_power and alpha_power default to the corresponding value set for luma_power.
A value of 0 will disable the effect ๐
Examples
Apply boxblur filter, setting each pixel of the output to the average value of box-radiuses luma_radius, chroma_radius, alpha_radius for each plane respectively. The filter will apply luma_power, chroma_power, alpha_power times onto the corresponding plane. For pixels on the edges of the image, the radius does not extend beyond the image boundaries, and so out-of-range coordinates are not used in the calculations.
- Apply a boxblur filter with the luma, chroma, and alpha radius set to 2 and luma, chroma, and alpha power set to 3. The filter will run 3 times with box-radius set to 2 for every plane of the image.
-i INPUT -vf "hwupload, boxblur_opencl=luma_radius=2:luma_power=3, hwdownload" OUTPUT
-i INPUT -vf "hwupload, boxblur_opencl=2:3, hwdownload" OUTPUT
- Apply a boxblur filter with luma radius set to 2, luma_power to 1, chroma_radius to 4, chroma_power to 5, alpha_radius to 3 and alpha_power to 7.
For the luma plane, a 2x2 box radius will be run once.
For the chroma plane, a 4x4 box radius will be run 5 times.
For the alpha plane, a 3x3 box radius will be run 7 times.
-i INPUT -vf "hwupload, boxblur_opencl=2:1:4:5:3:7, hwdownload" OUTPUT
๐ colorkey_opencl
RGB colorspace color keying ๐ literally making colors vanish.
The filter accepts the following options:
colorโ the color which will be replaced with transparency.similarityโ similarity percentage with the key color.0.01matches only the exact key color, while1.0matches everything ๐blendโ blend percentage.0.0makes pixels either fully transparent, or not transparent at all. Higher values result in semi-transparent pixels, with a higher transparency the more similar the pixels color is to the key color โจ
Examples
- Make every semi-green pixel in the input transparent with some slight blending:
-i INPUT -vf "hwupload, colorkey_opencl=green:0.3:0.1, hwdownload" OUTPUT
๐ convolution_opencl
Apply convolution of 3x3, 5x5, 7x7 matrix ๐ฅ math but make it fashion.
The filter accepts the following options:
0m,1m,2m,3mโ set matrix for each plane. Matrix is sequence of 9, 25 or 49 signed numbers. Default value for each plane is0 0 0 0 1 0 0 0 0.0rdiv,1rdiv,2rdiv,3rdivโ set multiplier for calculated value for each plane. If unset or0, it will be sum of all matrix elements. The option value must be a float number greater or equal to0.0. Default value is1.0.0bias,1bias,2bias,3biasโ set bias for each plane. This value is added to the result of the multiplication. Useful for making the overall image brighter or darker. The option value must be a float number greater or equal to0.0. Default value is0.0.
Examples
- Apply sharpen:
-i INPUT -vf "hwupload, convolution_opencl=0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0:0 -1 0 -1 5 -1 0 -1 0, hwdownload" OUTPUT
- Apply blur:
-i INPUT -vf "hwupload, convolution_opencl=1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1 1 1 1 1 1 1 1 1:1/9:1/9:1/9:1/9, hwdownload" OUTPUT
- Apply edge enhance:
-i INPUT -vf "hwupload, convolution_opencl=0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:0 0 0 -1 1 0 0 0 0:5:1:1:1:0:128:128:128, hwdownload" OUTPUT
- Apply edge detect:
-i INPUT -vf "hwupload, convolution_opencl=0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:0 1 0 1 -4 1 0 1 0:5:5:5:1:0:128:128:128, hwdownload" OUTPUT
- Apply laplacian edge detector which includes diagonals:
-i INPUT -vf "hwupload, convolution_opencl=1 1 1 1 -8 1 1 1 1:1 1 1 1 -8 1 1 1 1:1 1 1 1 -8 1 1 1 1:1 1 1 1 -8 1 1 1 1:5:5:5:1:0:128:128:0, hwdownload" OUTPUT
- Apply emboss:
-i INPUT -vf "hwupload, convolution_opencl=-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2:-2 -1 0 -1 1 1 0 1 2, hwdownload" OUTPUT
๐ธ erosion_opencl
Apply erosion effect to the video โ this filter replaces the pixel by the local(3x3) minimum ๐ณ๏ธ
It accepts the following options:
threshold0,threshold1,threshold2,threshold3โ limit the maximum change for each plane. Range is[0, 65535]and default value is65535. If0, plane will remain unchanged.coordinatesโ flag which specifies the pixel to refer to. Range is[0, 255]and default value is255, i.e. all eight pixels are used.
Flags to local 3x3 coordinates region centered on x:
1 2 3
4 x 5
6 7 8
Example
- Apply erosion filter with
threshold0set to 30,threshold1set 40,threshold2set to 50 andcoordinatesset to 231, setting each pixel of the output to the local minimum between pixels: 1, 2, 3, 6, 7, 8 of the 3x3 region centered on it in the input. If the difference between input pixel and local minimum is more then threshold of the corresponding plane, output pixel will be set to input pixel - threshold of corresponding plane.
-i INPUT -vf "hwupload, erosion_opencl=30:40:50:coordinates=231, hwdownload" OUTPUT
๐ฆ deshake_opencl
Feature-point based video stabilization filter ๐นโจ bye bye shaky cam.
The filter accepts the following options:
tripodโ simulates a tripod by preventing any camera movement whatsoever from the original frame. Defaults to0.debugโ whether or not additional debug info should be displayed, both in the processed output and in the console.
Note that in order to see console debug output you will also need to pass -v verbose to ffmpeg.
Viewing point matches in the output video is only supported for RGB input.
Defaults to 0.
adaptive_cropโ whether or not to do a tiny bit of cropping at the borders to cut down on the amount of mirrored pixels. Defaults to1.refine_featuresโ whether or not feature points should be refined at a sub-pixel level. This can be turned off for a slight performance gain at the cost of precision. Defaults to1.smooth_strengthโ the strength of the smoothing applied to the camera path from0.0to1.0.1.0is the maximum smoothing strength while values less than that result in less smoothing.0.0causes the filter to adaptively choose a smoothing strength on a per-frame basis. Defaults to0.0.smooth_window_multiplierโ controls the size of the smoothing window (the number of frames buffered to determine motion information from). The size of the smoothing window is determined by multiplying the framerate of the video by this number. Acceptable values range from0.1to10.0. Larger values increase the amount of motion data available for determining how to smooth the camera path, potentially improving smoothness, but also increase latency and memory usage. Defaults to2.0.
Examples
- Stabilize a video with a fixed, medium smoothing strength:
-i INPUT -vf "hwupload, deshake_opencl=smooth_strength=0.5, hwdownload" OUTPUT
- Stabilize a video with debugging (both in console and in rendered video):
-i INPUT -filter_complex "[0:v]format=rgba, hwupload, deshake_opencl=debug=1, hwdownload, format=rgba, format=yuv420p" -v verbose OUTPUT
๐ dilation_opencl
Apply dilation effect to the video ๐ this one replaces the pixel by the local(3x3) maximum.
It accepts the following options:
threshold0โ limits the max change for plane 0. Range:[0, 65535], default65535. If itโs0, that plane stays completely unchanged. ๐threshold1โ same vibe for plane 1: range[0, 65535], default65535; if0, plane stays unchanged.threshold2โ plane 2โs max-change cap. Range[0, 65535], default65535;0means no change.threshold3โ plane 3โs max-change cap. Range[0, 65535], default65535;0means no change.coordinatesโ flag that says which pixel to refer to. Range is[0, 255], default is255, i.e. all eight pixels are used. ๐
Flags map to a local 3x3 coordinate region centered on x:
1 2 3
4 x 5
6 7 8
๐ฆ Example
- Apply dilation filter with
threshold0set to30,threshold1set 40,threshold2set to50andcoordinatesset to231, setting each pixel of the output to the local maximum between pixels:1,2,3,6,7,8of the 3x3 region centered on it in the input. If the difference between input pixel and local maximum is more then threshold of the corresponding plane, output pixel will be set to input pixel + threshold of corresponding plane. โจ
-i INPUT -vf "hwupload, dilation_opencl=30:40:50:coordinates=231, hwdownload" OUTPUT
๐ nlmeans_opencl
Non-local Means denoise filter through OpenCL โ this filter accepts the same options as nlmeans. No cap, sheโs just borrowing the fit. ๐
๐ธ overlay_opencl
Overlay one video on top of another. It takes two inputs and has one output. The first input is the "main" video on which the second input is overlaid. This filter requires same memory layout for all the inputs, so format conversion may be needed. Lowkey important, bestie. ๐ซถ
The filter accepts the following options:
xโ set the x coordinate of the overlaid video on the main video. Default value is0.yโ set the y coordinate of the overlaid video on the main video. Default value is0.
๐ Examples
- Overlay an image
LOGOat the top-left corner of theINPUTvideo. Both inputs areyuv420pformat.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuv420p, hwupload[b], [a][b]overlay_opencl, hwdownload" OUTPUT
- The inputs have same memory layout for color channels, the overlay has additional alpha plane, like
INPUTisyuv420p, and theLOGOisyuva420p.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuva420p, hwupload[b], [a][b]overlay_opencl, hwdownload" OUTPUT
๐ง pad_opencl
Add paddings to the input image, and place the original input at the provided x, y coordinates. Itโs giving โmake room, main character incoming.โ ๐
It accepts the following options:
width,wandheight,hโ specify an expression for the size of the output image with the paddings added. If the value for width or height is0, the corresponding input size is used for the output. The width expression can reference the value set by the height expression, and vice versa. The default value ofwidthandheightis0.x,yโ specify the offsets to place the input image at within the padded area, with respect to the top/left border of the output image. The x expression can reference the value set by the y expression, and vice versa. The default value ofxandyis0. Ifxoryevaluate to a negative number, theyโll be changed so the input image is centered on the padded area. ๐colorโ specify the color of the padded area. For the syntax of this option, check the"Color"section in theffmpeg-utilsmanual.aspectโ pad to an aspect instead to a resolution.
The value for the width, height, x, and y options are expressions containing the following constants:
in_w,in_hโ the input video width and height.iw,ihโ these are the same asin_wandin_h.out_w,out_hโ the output width and height (the size of the padded area), as specified by thewidthandheightexpressions.ow,ohโ these are the same asout_wandout_h.x,yโ the x and y offsets as specified by thexandyexpressions, orNANif not yet specified.aโ same asiw / ih.sarโ input sample aspect ratio.darโ input display aspect ratio, it is the same as(iw / ih) * sar.
๐ฅ prewitt_opencl
Apply the Prewitt operator (https://en.wikipedia.org/wiki/Prewitt_operator) to input video stream. Edge-detection slay, no cap. โญ
The filter accepts the following option:
planesโ set which planes to filter. Default value is0xf, by which all planes are processed.scaleโ set value which will be multiplied with filtered result. Range is[0.0, 65535]and default value is1.0.deltaโ set value which will be added to filtered result. Range is[-65535, 65535]and default value is0.0.
๐ Example
- Apply the Prewitt operator with
scaleset to2anddeltaset to10.
-i INPUT -vf "hwupload, prewitt_opencl=scale=2:delta=10, hwdownload" OUTPUT
๐ program_opencl
Filter video using an OpenCL program. Custom kernel realness. ๐
sourceโ OpenCL program source file.kernelโ kernel name in program.inputsโ number of inputs to the filter. Defaults to1.size,sโ size of output frames. Defaults to the same as the first input.
The program_opencl filter also supports the framesync options.
The program source file must contain a kernel function with the given name, which will be run once for each plane of the output. Each run on a plane gets enqueued as a separate 2D global NDRange with one work-item for each pixel to be generated. The global ID offset for each work-item is therefore the coordinates of a pixel in the destination image. โจ
The kernel function needs to take the following arguments:
- Destination image,
__write_only image2d_t. This image will become the output; the kernel should write all of it. - Frame index,
unsigned int. This is a counter starting from zero and increasing by one for each frame. - Source images,
__read_only image2d_t. These are the most recent images on each input. The kernel may read from them to generate the output, but they canโt be written to.
๐ง Example programs
- Copy the input to the output (output must be the same size as the input).
__kernel void copy(__write_only image2d_t destination,
unsigned int index,
__read_only image2d_t source)
{
const sampler_t sampler = CLK_NORMALIZED_COORDS_FALSE;
int2 location = (int2)(get_global_id(0), get_global_id(1));
float4 value = read_imagef(source, sampler, location);
write_imagef(destination, location, value);
}
- Apply a simple transformation, rotating the input by an amount increasing with the index counter. Pixel values are linearly interpolated by the sampler, and the output need not have the same dimensions as the input.
__kernel void rotate_image(__write_only image2d_t dst,
unsigned int index,
__read_only image2d_t src)
{
const sampler_t sampler = (CLK_NORMALIZED_COORDS_FALSE |
CLK_FILTER_LINEAR);
float angle = (float)index / 100.0f;
float2 dst_dim = convert_float2(get_image_dim(dst));
float2 src_dim = convert_float2(get_image_dim(src));
float2 dst_cen = dst_dim / 2.0f;
float2 src_cen = src_dim / 2.0f;
int2 dst_loc = (int2)(get_global_id(0), get_global_id(1));
float2 dst_pos = convert_float2(dst_loc) - dst_cen;
float2 src_pos = {
cos(angle) * dst_pos.x - sin(angle) * dst_pos.y,
sin(angle) * dst_pos.x + cos(angle) * dst_pos.y
};
src_pos = src_pos * src_dim / dst_dim;
float2 src_loc = src_pos + src_cen;
if (src_loc.x < 0.0f || src_loc.y < 0.0f ||
src_loc.x > src_dim.x || src_loc.y > src_dim.y)
write_imagef(dst, dst_loc, 0.5f);
else
write_imagef(dst, dst_loc, read_imagef(src, sampler, src_loc));
}
- Blend two inputs together, with the amount of each input used varying with the index counter.
__kernel void blend_images(__write_only image2d_t dst,
unsigned int index,
__read_only image2d_t src1,
__read_only image2d_t src2)
{
const sampler_t sampler = (CLK_NORMALIZED_COORDS_FALSE |
CLK_FILTER_LINEAR);
float blend = (cos((float)index / 50.0f) + 1.0f) / 2.0f;
int2 dst_loc = (int2)(get_global_id(0), get_global_id(1));
int2 src1_loc = dst_loc * get_image_dim(src1) / get_image_dim(dst);
int2 src2_loc = dst_loc * get_image_dim(src2) / get_image_dim(dst);
float4 val1 = read_imagef(src1, sampler, src1_loc);
float4 val2 = read_imagef(src2, sampler, src2_loc);
write_imagef(dst, dst_loc, val1 * blend + val2 * (1.0f - blend));
}
๐ remap_opencl
Remap pixels using 2nd: Xmap and 3rd: Ymap input video stream. Itโs giving โpixel teleportation.โ ๐ฆ
Destination pixel at position (X, Y) will be picked from source (x, y) position where x = Xmap(X, Y) and y = Ymap(X, Y). If mapping values are out of range, zero value for pixel will be used for destination pixel.
Xmap and Ymap input video streams must be of same dimensions. Output video stream will have Xmap/Ymap video stream dimensions. Xmap and Ymap input video streams are 32bit float pixel format, single channel. ๐ซถ
interpโ specify interpolation used for remapping of pixels. Allowed values are"near"and"linear". Default value is"linear".fillโ specify the color of the unmapped pixels. For the syntax of this option, check the"Color"section in theffmpeg-utilsmanual. Default color is"black".
๐ roberts_opencl
Apply the Roberts cross operator (https://en.wikipedia.org/wiki/Roberts_cross) to input video stream. Another icon behavior. ๐
The filter accepts the following option:
planesโ set which planes to filter. Default value is0xf, by which all planes are processed.scaleโ set value which will be multiplied with filtered result. Range is[0.0, 65535]and default value is1.0.deltaโ set value which will be added to filtered result. Range is[-65535, 65535]and default value is0.0.
๐ Example
- Apply the Roberts cross operator with
scaleset to2anddeltaset to10.
-i INPUT -vf "hwupload, roberts_opencl=scale=2:delta=10, hwdownload" OUTPUT
๐ sobel_opencl
Okay so this one literally applies the Sobel operator (<https://en.wikipedia.org/wiki/Sobel_operator>) to your input video stream. Edge detection core, iconic, no notes.
The filter accepts the following option:
planesโ sets which planes get filtered. Default value is0xf, which means all the planes get processed. Slay.scaleโ sets the value that gets multiplied with the filtered result. Range is[0.0, 65535]and default value is1.0.deltaโ sets the value that gets added to the filtered result. Range is[-65535, 65535]and default value is0.0.
๐ Example
- Apply sobel operator with
scaleset to2anddeltaset to10:
-i INPUT -vf "hwupload, sobel_opencl=scale=2:delta=10, hwdownload" OUTPUT
๐ tonemap_opencl
This one performs HDR(PQ/HLG) to SDR conversion with tone-mapping. It's giving "make your HDR footage actually watchable on a normal screen" energy ๐
It accepts the following parameters:
tonemapโ specify the tone-mapping operator to be used. Same as thetonemapoption intonemap.paramโ tune the tone mapping algorithm. Same as theparamoption intonemap.desatโ apply desaturation for highlights that exceed this level of brightness. The higher the parameter, the more color information will be preserved. This setting helps prevent unnaturally blown-out colors for super-highlights, by (smoothly) turning into white instead. This makes images feel more natural, at the cost of reducing information about out-of-range colors.
The default value is 0.5, and the algorithm here is a little different from the cpu version tonemap currently. A setting of 0.0 disables this option.
thresholdโ the tonemapping algorithm parameters is fine-tuned per each scene. And a threshold is used to detect whether the scene has changed or not. If the distance between the current frame average brightness and the current running average exceeds a threshold value, we would re-calculate scene average and peak brightness. The default value is0.2.formatโ specify the output pixel format.
Currently supported formats are:
p010nv12
range,rโ set the output color range.
Possible values are:
tv/mpegpc/jpeg
Default is same as input.
primaries,pโ set the output color primaries.
Possible values are:
bt709bt2020
Default is same as input.
transfer,tโ set the output transfer characteristics.
Possible values are:
bt709bt2020
Default is bt709.
matrix,mโ set the output colorspace matrix.
Possible value are:
bt709bt2020
Default is same as input.
๐ฆ Example
- Convert HDR(PQ/HLG) video to bt2020-transfer-characteristic p010 format using linear operator:
-i INPUT -vf "format=p010,hwupload,tonemap_opencl=t=bt2020:tonemap=linear:format=p010,hwdownload,format=p010" OUTPUT
โจ unsharp_opencl
Sharpen or blur the input video. Your one-stop glow-up (or soft-focus) shop, bestie ๐
It accepts the following parameters:
luma_msize_x,lxโ set the luma matrix horizontal size. Range is[1, 23]and default value is5.luma_msize_y,lyโ set the luma matrix vertical size. Range is[1, 23]and default value is5.luma_amount,laโ set the luma effect strength. Range is[-10, 10]and default value is1.0.
Negative values will blur the input video, while positive values will sharpen it, a value of zero will disable the effect.
chroma_msize_x,cxโ set the chroma matrix horizontal size. Range is[1, 23]and default value is5.chroma_msize_y,cyโ set the chroma matrix vertical size. Range is[1, 23]and default value is5.chroma_amount,caโ set the chroma effect strength. Range is[-10, 10]and default value is0.0.
Negative values will blur the input video, while positive values will sharpen it, a value of zero will disable the effect.
All parameters are optional and default to the equivalent of the string '5:5:1.0:5:5:0.0'. So if you just raw-dog it with no options, that's the vibe you're getting ๐ซถ
๐ธ Examples
- Apply strong luma sharpen effect:
-i INPUT -vf "hwupload, unsharp_opencl=luma_msize_x=7:luma_msize_y=7:luma_amount=2.5, hwdownload" OUTPUT
- Apply a strong blur of both luma and chroma parameters:
-i INPUT -vf "hwupload, unsharp_opencl=7:7:-2:7:7:-2, hwdownload" OUTPUT
๐ฅ xfade_opencl
Cross fade two videos with custom transition effect by using OpenCL. Two videos walk in, one video walks out โ main character energy fr fr ๐
It accepts the following options:
transitionโ set one of possible transition effects.customโ select custom transition effect, the actual transition description will be picked fromsourceandkerneloptions.fadewipeleftwiperightwipeupwipedownslideleftsliderightslideupslidedown
Default transition is fade.
sourceโ OpenCL program source file for custom transition.kernelโ set name of kernel to use for custom transition from program source file.durationโ set duration of video transition.offsetโ set time of start of transition relative to first video.
The program source file must contain a kernel function with the given name, which will be run once for each plane of the output. Each run on a plane gets enqueued as a separate 2D global NDRange with one work-item for each pixel to be generated. The global ID offset for each work-item is therefore the coordinates of a pixel in the destination image.
The kernel function needs to take the following arguments:
- Destination image,
__write_only image2d_t.
This image will become the output; the kernel should write all of it.
- First Source image,
__read_only image2d_t. Second Source image,__read_only image2d_t.
These are the most recent images on each input. The kernel may read from them to generate the output, but they can't be written to.
- Transition progress,
float. This value is always between 0 and 1 inclusive.
Example programs:
- Apply dots curtain transition effect:
__kernel void blend_images(__write_only image2d_t dst,
__read_only image2d_t src1,
__read_only image2d_t src2,
float progress)
{
const sampler_t sampler = (CLK_NORMALIZED_COORDS_FALSE |
CLK_FILTER_LINEAR);
int2 p = (int2)(get_global_id(0), get_global_id(1));
float2 rp = (float2)(get_global_id(0), get_global_id(1));
float2 dim = (float2)(get_image_dim(src1).x, get_image_dim(src1).y);
rp = rp / dim;
float2 dots = (float2)(20.0, 20.0);
float2 center = (float2)(0,0);
float2 unused;
float4 val1 = read_imagef(src1, sampler, p);
float4 val2 = read_imagef(src2, sampler, p);
bool next = distance(fract(rp * dots, &unused), (float2)(0.5, 0.5)) < (progress / distance(rp, center));
write_imagef(dst, p, next ? val1 : val2);
}
โจ VAAPI VIDEO FILTERS โจ
Okay bestie, so VAAPI Video filters are usually used with a VAAPI decoder and a VAAPI encoder. Below is the description of VAAPI video filters. ๐
To enable compilation of these filters you need to configure FFmpeg with --enable-vaapi.
To use vaapi filters, you need to setup the vaapi device correctly. For more information, please read https://trac.ffmpeg.org/wiki/Hardware/VAAPI.
๐ overlay_vaapi
Overlay one video on the top of another.
It takes two inputs and has one output. The first input is the main video on which the second input is overlaid. Main character energy fr fr.
The filter accepts the following options:
x,yโ Set expressions for the x and y coordinates of the overlaid video on the main video. Default value is0for both expressions.w,hโ Set expressions for the width and height of the overlaid video on the main video. Default values areoverlay_iwforwandoverlay_ih*w/overlay_iwforh.
The expressions can contain the following parameters:
main_w,Wโ The main input width.main_h,Hโ The main input height.overlay_iwโ The overlay input width.overlay_ihโ The overlay input height.overlay_w,wโ The overlay output width.overlay_h,hโ The overlay output height.overlay_x,xโ Position of the overlay layer inside of main.overlay_y,yโ Position of the overlay layer inside of main.
alphaโ Set transparency of overlaid video. Allowed range is0.0to1.0. Higher value means lower transparency. Default value is1.0.eof_actionโ See framesync.shortestโ See framesync.repeatlastโ See framesync.
This filter also supports the framesync options.
โจ Examples โจ
- Top-left LOGO overlay: Overlay an image LOGO at the top-left corner of the INPUT video. Both inputs for this filter are yuv420p format.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuv420p, hwupload[b], [a][b]overlay_vaapi" OUTPUT
- Offset overlay at (200, 100): Overlay an image LOGO at the offset (200, 100) from the top-left corner of the INPUT video. The inputs have same memory layout for color channels, the overlay has additional alpha plane, like INPUT is yuv420p, and the LOGO is yuva420p.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuva420p, hwupload[b], [a][b]overlay_vaapi=x=200:y=100:w=400:h=300:alpha=1.0, hwdownload, format=nv12" OUTPUT
๐ tonemap_vaapi
Perform HDR-to-SDR or HDR-to-HDR tone-mapping. It currently only accepts HDR10 as input. We love a format with range.
It accepts the following parameters:
formatโ Specify the output pixel format. Default isnv12for HDR-to-SDR tone-mapping andp010for HDR-to-HDR tone-mapping.primaries,pโ Set the output color primaries. Default isbt709for HDR-to-SDR tone-mapping and same as input for HDR-to-HDR tone-mapping.transfer,tโ Set the output transfer characteristics. Default isbt709for HDR-to-SDR tone-mapping and same as input for HDR-to-HDR tone-mapping.matrix,mโ Set the output colorspace matrix. Default isbt709for HDR-to-SDR tone-mapping and same as input for HDR-to-HDR tone-mapping.displayโ Set the output mastering display colour volume. It is given by a'|'-separated list of two values, two values are space separated. It sets display primaries x & y in G, B, R order, then white point x & y, the nominal minimum & maximum display luminances. HDR-to-HDR tone-mapping will be performed when this option is set.lightโ Set the output content light level information. It accepts 2 space-separated values, the first input is the maximum light level and the second input is the maximum average light level. It is ignored for HDR-to-SDR tone-mapping, and optional for HDR-to-HDR tone-mapping.
โจ Example โจ
- HDR10 to p010: Convert HDR(HDR10) video to bt2020-transfer-characteristic p010 format.
tonemap_vaapi=format=p010:t=bt2020-10
- HDR to HDR: Convert HDR video to HDR video.
tonemap_vaapi=display=7500\ 3000|34000\ 16000|13250\ 34500|15635\ 16450|500\ 10000000
๐ฆ hstack_vaapi
Stack input videos horizontally.
This is the VA-API variant of the hstack filter. Each input stream may have different height, and this filter will scale down/up each input stream while keeping the original aspect. Side-by-side slay.
It accepts the following options:
inputsโ Seehstack.shortestโ Seehstack.heightโ Set height of output. If set to0, this filter will set height of output to height of the first input stream. Default value is0.
๐ธ vstack_vaapi
Stack input videos vertically.
This is the VA-API variant of the vstack filter. Each input stream may have different width, and this filter will scale down/up each input stream while keeping the original aspect.
It accepts the following options:
inputsโ Seevstack.shortestโ Seevstack.widthโ Set width of output. If set to0, this filter will set width of output to width of the first input stream. Default value is0.
๐ xstack_vaapi
Stack video inputs into custom layout.
This is the VA-API variant of the xstack filter. Each input stream may have different size, and this filter will scale down/up each input stream to the given output size, or the size of the first input stream. Custom layout = main character energy.
It accepts the following options:
inputsโ Seexstack.shortestโ Seexstack.layoutโ Seexstack. Moreover, this permits the user to supply output size for each input stream.
xstack_vaapi=inputs=4:layout=0_0_1920x1080|0_h0_1920x1080|w0_0_1920x1080|w0_h0_1920x1080
gridโ Seexstack.grid_tile_sizeโ Set output size for each input stream when grid is set. If this option is not set, this filter will set output size by default to the size of the first input stream. For the syntax of this option, check theVideo sizesection in the ffmpeg-utils manual.fillโ Seexstack.
๐ pad_vaapi
Add paddings to the input image, and place the original input at the provided x, y coordinates.
It accepts the following options:
width,wandheight,hโ Specify an expression for the size of the output image with the paddings added. If the value for width or height is0, the corresponding input size is used for the output. The width expression can reference the value set by the height expression, and vice versa. The default value of width and height is0.x,yโ Specify the offsets to place the input image at within the padded area, with respect to the top/left border of the output image. The x expression can reference the value set by the y expression, and vice versa. The default value of x and y is0. If x or y evaluate to a negative number, they'll be changed so the input image is centered on the padded area.colorโ Specify the color of the padded area. For the syntax of this option, check theColorsection in the ffmpeg-utils manual.aspectโ Pad to an aspect instead to a resolution.
The value for the width, height, x, and y options are expressions containing the following constants:
in_w,in_hโ The input video width and height.iw,ihโ These are the same asin_wandin_h.out_w,out_hโ The output width and height (the size of the padded area), as specified by the width and height expressions.ow,ohโ These are the same asout_wandout_h.x,yโ The x and y offsets as specified by the x and y expressions, orNANif not yet specified.aโ same asiw / ih.sarโ input sample aspect ratio.darโ input display aspect ratio, it is the same as(iw / ih) * sar.
๐ drawbox_vaapi
Draw a colored box on the input image. Arts and crafts era.
It accepts the following parameters:
x,yโ The expressions which specify the top left corner coordinates of the box. It defaults to0.width,wandheight,hโ The expressions which specify the width and height of the box; if0they are interpreted as the input width and height. It defaults to0.color,cโ Specify the color of the box to write. For the general syntax of this option, check theColorsection in the ffmpeg-utils manual.thickness,tโ The expression which sets the thickness of the box edge. A value offillwill create a filled box. Default value is3. See below for the list of accepted constants.replaceโ With value1, the pixels of the painted box will overwrite the video's color and alpha pixels. Default is0, which composites the box onto the input video.
The parameters for x, y, w and h and t are expressions containing the following constants:
in_h,ihโ The input height.in_w,iwโ The input width.x,yโ The x and y offset coordinates where the box is drawn.w,hโ The width and height of the drawn box.tโ The thickness of the drawn box.
โจ Examples โจ
- Black border box: Draw a black box around the edge of the input image.
drawbox
- Red box with 50% opacity: Draw a box with color red and an opacity of 50%.
drawbox=10:20:200:60:red@0.5
The previous example can be specified as:
drawbox=x=10:y=20:w=200:h=60:color=red@0.5
- Pink filled box: Fill the box with pink color.
drawbox=x=10:y=10:w=100:h=100:color=pink@0.5:t=fill
- Red 2.40:1 mask: Draw a 2-pixel red 2.40:1 mask.
drawbox=x=-t:y=0.5*(ih-iw/2.4)-t:w=iw+t*2:h=iw/2.4+t*2:t=2:c=red
๐ป VIDEOTOOLBOX VIDEO FILTERS ๐ป
Okay bestie, so this is the little crew of VideoToolbox video filters we've got rn โ here's the rundown on each one ๐
The VideoToolbox filter depends on the VideoToolbox framework, and it gets auto-detected when you're building ffmpeg for an Apple platform like macOS. If autodetect is disabled for some reason, just add --enable-videotoolbox to configure and you're golden โจ
๐ฆ scale_vt
This one scales and converts the color parameters using VTPixelTransferSession โ two jobs, one filter, we love an efficient queen ๐
The filter accepts the following options:
whโ Set the output video dimension expression. Default value is the input dimension. (So if you don't say anything, it just keeps whatever size you gave it, no drama ๐ )color_matrixโ Set the output colorspace matrix.color_primariesโ Set the output color primaries.color_transferโ Set the output transfer characteristics.
๐ธ Examples
- Perform HDR to SDR conversion, and scale to half size of input:
ffmpeg -hwaccel videotoolbox \
-hwaccel_output_format videotoolbox_vld \
-i hdr.mov \
-c:v hevc_videotoolbox \
-profile:v main \
-b:v 3M \
-vf scale_vt=w=iw/2:h=ih/2:color_matrix=bt709:color_primaries=bt709:color_transfer=bt709 \
-c:a copy \
-tag:v hvc1 \
sdr.mp4
Like, look at her go โ HDR in, SDR out, half the size, audio copied straight through, hvc1 tag slapped on at the end. Iconic behavior fr fr ๐ฅ
๐ง transpose_vt
This one transposes rows with columns in the input video, and optionally flips it too. For more in-depth examples, go peek at the transpose video filter โ it shares mostly the same options, so you already kinda know her ๐ซถ
It accepts the following parameters:
dirโ Specify the transposition direction.
Can assume the following values:
cclock_flipโ Rotate by 90 degrees counterclockwise and vertically flip. (default) โ yeah she's the default, don't come for her ๐clockโ Rotate by 90 degrees clockwise.cclockโ Rotate by 90 degrees counterclockwise.clock_flipโ Rotate by 90 degrees clockwise and vertically flip.hflipโ Flip the input video horizontally.vflipโ Flip the input video vertically.
passthroughโ Do not apply the transposition if the input geometry matches the one specified by the specified value. It accepts the following values:noneโ Always apply transposition. (default)portraitโ Preserve portrait geometry (when height >= width).landscapeโ Preserve landscape geometry (when width >= height).
Lowkey the passthrough option is the "respect the vibe of the original" switch โ set it and she'll skip the whole transpose if your geometry already matches. Very considerate, very demure โจ
๐ฅ VULKAN VIDEO FILTERS ๐ฅ
okay bestie, buckle up โ here's the rundown on all the Vulkan video filters we currently ship. GPU go brrr ๐
So to even compile these filters you gotta configure FFmpeg with --enable-vulkan and either --enable-libglslang or --enable-libshaderc. Both, like, pick one of the last two, but you need the vulkan one regardless. No cap. โจ
And running Vulkan filters means you have to initialize a hardware device and then pass that device to all the filters in any filter graph. Every single one. The whole squad. ๐ซถ
-init_hw_device vulkan[=name][:device[,key=value...]]โ Initialises a shiny new hardware device of typevulkancalled name, using the device parameters and options you give it inkey=value. Here's what's supported:debugโ Switches validation layers on if set to1.linear_imagesโ Allocates linear images. Nope, does not apply to decoding.disable_multiplaneโ Disables multiplane images. Also does not apply to decoding.avoid_host_importโ Avoids using dynamic host memory imports, in favor of a regularmemcpy()into a previously mapped buffer.
-filter_hw_device nameโ Passes the hardware device called name to all filters in any filter graph.
For way more detailed info, go peek at <https://www.ffmpeg.org/ffmpeg.html#Advanced-Video-options> ๐
- ๐ Example of choosing the first device and running
nlmeans_vulkanwith default parameters on it:
-init_hw_device vulkan=vk:0 -filter_hw_device vk -i INPUT -vf "hwupload,nlmeans_vulkan,hwdownload" OUTPUT
Here's the tea though: Vulkan filters cannot access frame data in normal memory ๐ญ so all frame data needs to be uploaded (hwupload) to hardware surfaces connected to the appropriate device before being used, and then downloaded (hwdownload) back to normal memory. Important detail: hwupload will upload to a frame with the same layout as the software frame, so you may need to add a format filter immediately before it to get your input into the right format. And hwdownload does not support all formats on the output โ usually you gotta insert an additional format filter immediately following in the graph to get the output into a supported format. Annoying but iconic, that's just how it is ๐
โจ avgblur_vulkan
Applies an average blur filter, implemented on the GPU using Vulkan.
It accepts the following options:
sizeXโ Sets the horizontal radius size. Range is[1, 32], default value is3.sizeYโ Sets the vertical radius size. Range is[1, 32], default value is3.planesโ Sets which planes to filter. Default value is0xf, which means all planes get processed. ๐
๐ฆ blend_vulkan
Blends two Vulkan frames into each other. Literally mixing vibes.
The blend filter takes two input streams and outputs one stream โ first input is the "top" layer and second input is the "bottom" layer. By default, the output terminates when the longest input terminates.
A description of the accepted options follows:
c0_modec1_modec2_modec3_modeall_modeโ Sets the blend mode for a specific pixel component, or for all pixel components in the case ofall_mode. Default value is"normal".
Available values for component modes are:
normalmultiply
๐ธ bwdif_vulkan
A deinterlacer using bwdif, the "Bob Weaver Deinterlacing Filter" algorithm, implemented on the GPU using Vulkan. Look at that name, so main character ๐ซ
It accepts the following parameters:
modeโ The interlacing mode to adopt. It accepts one of these:0,send_frameโ Output one frame for each frame.1,send_fieldโ Output one frame for each field.
Default value is "send_field".
parityโ The picture field parity assumed for the input interlaced video. Accepts one of:0,tffโ Assume the top field is first.1,bffโ Assume the bottom field is first.-1,autoโ Enables automatic detection of field parity.
Default value is "auto". Heads up: if the interlacing is unknown or the decoder doesn't export this information, top field first will be assumed.
deintโ Specifies which frames to deinterlace. Accepts one of:0,allโ Deinterlace all frames.1,interlacedโ Only deinterlace frames marked as interlaced.
Default value is "all".
๐ chromaber_vulkan
Applies an effect that emulates chromatic aberration. Works best with RGB inputs, but honestly gives a similar vibe with YCbCr inputs too.
dist_xโ Horizontal displacement multiplier. Each chroma pixel's position gets multiplied by this amount, starting from the center of the image. Default is0.dist_yโ Same energy, but this sets the vertical displacement multiplier. Default is0.
๐ color_vulkan
A video source that creates a Vulkan frame of a solid color. Super useful for benchmarking, or overlaying. ๐ฏ
It accepts the following parameters:
colorโ The color to use. Either a name, or a hexadecimal value. Default value is"black".sizeโ The size of the output frame. Default value is"1920x1080".rateโ The framerate to output at. Default value is60frames per second.durationโ The video duration. Default value is-0.000001.sarโ The video signal aspect ratio. Default value is"1/1".formatโ The pixel format of the output Vulkan frames. Default value is"yuv444p".out_rangeโ Sets the output YCbCr sample range.
This lets you override the autodetected value, and also lets you force a specific value used for the output and encoder. If not specified, the range depends on the pixel format. Possible values:
auto/unknownโ Choose automatically.jpeg/full/pcโ Set full range (0-255in case of 8-bit luma).mpeg/limited/tvโ Set"MPEG"range (16-235in case of 8-bit luma).
๐ง vflip_vulkan
Flips an image vertically. Upside down bestie ๐
๐ง hflip_vulkan
Flips an image horizontally. Mirror mirror ๐ช
๐ง flip_vulkan
Flips an image along both the vertical and horizontal axis. Double flip, double slay.
๐ gblur_vulkan
Applies a Gaussian blur filter on Vulkan frames. Soft focus aesthetic โจ
The filter accepts the following options:
sigmaโ Sets horizontal sigma, standard deviation of Gaussian blur. Default is0.5.sigmaVโ Sets vertical sigma; if negative it will be the same assigma. Default is-1.planesโ Sets which planes to filter. By default all planes are filtered.sizeโ Sets the kernel size along the horizontal axis. Default is19.sizeVโ Sets the kernel size along the vertical axis. Default is0, which sets it to use the same value assize.
๐ nlmeans_vulkan
Denoises frames using the Non-Local Means algorithm, implemented on the GPU using Vulkan. It supports more pixel formats than nlmeans or nlmeans_opencl, including alpha channel support. Obsessed with the range honestly ๐ฅ
The filter accepts the following options:
sโ Sets denoising strength for all components. Default is1.0. Must be in range[0.0, 100.0].pโ Sets patch size for all planes. Default is7. Must be an odd number in range[0, 99].rโ Sets research size. Default is15. Must be an odd number in range[0, 99].tโ Sets parallelism. Default is8. Must be a number in the range[1, 64]. Larger values will use more VRAM but may not actually result in greater speed โ the optimal value is hardware and input dependent, so like, don't just crank it ๐ญs0s1s2s3โ Sets denoising strength for a specific component. Default is1.0, equal tos. Must be in range[0.0, 100.0]. Setting0.0disables denoising in that component.p0p1p2p3โ Sets patch size for a specific component. Default is7, equal top. Must be an odd number in range[0, 99].
๐ overlay_vulkan
Overlays one video on top of another.
It takes two inputs and has one output. The first input is the "main" video, and the second input is overlaid on top of it. Lowkey important: this filter requires all inputs to use the same pixel format. So, format conversion may be needed. Plan ahead bestie ๐ซถ
The filter accepts the following options:
xโ Sets the x coordinate of the overlaid video on the main video. Default value is0.yโ Sets the y coordinate of the overlaid video on the main video. Default value is0.
๐ transpose_vulkan
Transposes rows with columns in the input video, and optionally flips it. For more in-depth examples check out the transpose video filter, which shares mostly the same options. iykyk ๐ซ
It accepts the following parameters:
dirโ Specifies the transposition direction.
Can assume the following values:
cclock_flipโ Rotate by 90 degrees counterclockwise and vertically flip. (default)clockโ Rotate by 90 degrees clockwise.cclockโ Rotate by 90 degrees counterclockwise.clock_flipโ Rotate by 90 degrees clockwise and vertically flip.
passthroughโ Does not apply the transposition if the input geometry matches the one specified by the given value. It accepts the following values:noneโ Always apply transposition. (default)portraitโ Preserve portrait geometry (whenheight >= width).landscapeโ Preserve landscape geometry (whenwidth >= height).
โจ QSV VIDEO FILTERS โจ
okay so these are the QSV filters that are currently available, bestie ๐
to even compile these filters you gotta configure FFmpeg with --enable-libmfx or --enable-libvpl. like, both exist, pick your fighter ๐ซถ
and to actually use QSV filters you need to set up the QSV device correctly first. for more info pls go read <https://trac.ffmpeg.org/wiki/Hardware/QuickSync> โ it's giving required reading, ngl ๐
๐ hstack_qsv
Stacks input videos horizontally. literally side-by-side vibes โจ
This is the QSV variant of the hstack filter, and the way it works: each input stream may have a different height, and this filter will scale down/up each input stream while keeping the original aspect. no squishing, we respect the aspect ratio ๐
It accepts the following options:
inputsโ seehstack. iykykshortestโ seehstack.heightโ Set height of output. If set to0, this filter will set height of output to height of the first input stream. Default value is0.
๐ฆ vstack_qsv
Stacks input videos vertically. stacking upward, main character energy going down the screen ๐
This is the QSV variant of the vstack filter, each input stream may have different width, this filter will scale down/up each input stream while keeping the original aspect.
It accepts the following options:
inputsโ seevstack.shortestโ seevstack.widthโ Set width of output. If set to0, this filter will set width of output to width of the first input stream. Default value is0.
๐ xstack_qsv
Stack video inputs into custom layout. yes custom, you're the layout designer now ๐
This is the QSV variant of the xstack filter.
It accepts the following options:
inputsโ seexstack.shortestโ seexstack.layoutโ seexstack. Moreover, this permits the user to supply output size for each input stream. like so:
xstack_qsv=inputs=4:layout=0_0_1920x1080|0_h0_1920x1080|w0_0_1920x1080|w0_h0_1920x1080
gridโ seexstack.grid_tile_sizeโ Set output size for each input stream whengridis set. If this option is not set, this filter will set output size by default to the size of the first input stream. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual.fillโ seexstack.
๐ธ VIDEO SOURCES ๐ธ
Below is a description of the currently available video sources. ok so these are where your video comes from, the origin story if you will ๐ง
๐ buffer
Buffer video frames, and make them available to the filter chain. it's literally the bridge ok ๐ซถ
This source is mainly intended for a programmatic use, in particular through the interface defined in libavfilter/buffersrc.h.
It accepts the following parameters:
video_sizeโ Specify the size (width and height) of the buffered video frames. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual.widthโ The input video width.heightโ The input video height.pix_fmtโ A string representing the pixel format of the buffered video frames. It may be a number corresponding to a pixel format, or a pixel format name.time_baseโ Specify the timebase assumed by the timestamps of the buffered frames.frame_rateโ Specify the frame rate expected for the video stream.colorspaceโ A string representing the color space of the buffered video frames. It may be a number corresponding to a color space, or a color space name.rangeโ A string representing the color range of the buffered video frames. It may be a number corresponding to a color range, or a color range name.alpha_modeโ A string representing the alpha mode of the buffered video frames. It may be a number corresponding to an alpha mode, or an alpha mode name.pixel_aspect,sarโ The sample (pixel) aspect ratio of the input video.hw_frames_ctxโ When using a hardware pixel format, this should be a reference to anAVHWFramesContextdescribing input frames.
For example:
buffer=width=320:height=240:pix_fmt=yuv410p:time_base=1/24:sar=1
will instruct the source to accept video frames with size 320x240 and with format yuv410p, assuming 1/24 as the timestamps timebase and square pixels (1:1 sample aspect ratio). Since the pixel format with name yuv410p corresponds to the number 6 (check the enum AVPixelFormat definition in libavutil/pixfmt.h), this example corresponds to:
buffer=size=320x240:pixfmt=6:time_base=1/24:pixel_aspect=1/1
Alternatively, the options can be specified as a flat string, but this syntax is deprecated:
width:height:pix_fmt:time_base.num:time_base.den:pixel_aspect.num:pixel_aspect.den
fr fr don't use that flat string version, it's giving legacy ๐ญ
โญ cellauto
Create a pattern generated by an elementary cellular automaton. yes it's math, yes it's gorgeous, no I will not elaborate ๐ โจ
The initial state of the cellular automaton can be defined through the filename and pattern options. If such options are not specified an initial state is created randomly. chaos as a treat ๐ฒ
At each new frame a new row in the video is filled with the result of the cellular automaton next generation. The behavior when the whole frame is filled is defined by the scroll option.
This source accepts the following options:
filename,fโ Read the initial cellular automaton state, i.e. the starting row, from the specified file. In the file, each non-whitespace character is considered an alive cell, a newline will terminate the row, and further characters in the file will be ignored.pattern,pโ Read the initial cellular automaton state, i.e. the starting row, from the specified string. Each non-whitespace character in the string is considered an alive cell, a newline will terminate the row, and further characters in the string will be ignored.rate,rโ Set the video rate, that is the number of frames generated per second. Default is25.random_fill_ratio,ratioโ Set the random fill ratio for the initial cellular automaton row. It is a floating point number value ranging from0to1, defaults to1/PHI. This option is ignored when a file or a pattern is specified.random_seed,seedโ Set the seed for filling randomly the initial row, must be an integer included between0andUINT32_MAX. If not specified, or if explicitly set to-1, the filter will try to use a good random seed on a best effort basis.ruleโ Set the cellular automaton rule, it is a number ranging from0to255. Default value is110.size,sโ Set the size of the output video. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual. Iffilenameorpatternis specified, the size is set by default to the width of the specified initial state row, and the height is set to width * PHI. Ifsizeis set, it must contain the width of the specified pattern string, and the specified pattern will be centered in the larger row. If a filename or a pattern string is not specified, the size value defaults to320x518(used for a randomly generated initial state).scrollโ If set to1, scroll the output upward when all the rows in the output have been already filled. If set to0, the new generated row will be written over the top row just after the bottom row is filled. Defaults to1.start_full,fullโ If set to1, completely fill the output with generated rows before outputting the first frame. This is the default behavior, for disabling set the value to0.stitchโ If set to1, stitch the left and right row edges together. This is the default behavior, for disabling set the value to0.
๐ Examples
- Read the initial state from
pattern, and specify an output of size200x400.
cellauto=f=pattern:s=200x400
- Generate a random initial row with a width of
200cells, with a fill ratio of2/3:
cellauto=ratio=2/3:s=200x200
- Create a pattern generated by rule
18starting by a single alive cell centered on an initial row with width100:
cellauto=p=@s=100x400:full=0:rule=18
- Specify a more elaborated initial pattern:
cellauto=p='@@ @ @@':s=100x400:full=0:rule=18
๐ฆ coreimagesrc
Video source generated on GPU using Apple's CoreImage API on OSX. apple girlies rise ๐
This video source is a specialized version of the coreimage video filter. Use a core image generator at the beginning of the applied filterchain to generate the content.
The coreimagesrc video source accepts the following options:
list_generatorsโ List all available generators along with all their respective options as well as possible minimum and maximum values along with the default values.
list_generators=true
size,sโ Specify the size of the sourced video. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual. The default value is320x240.rate,rโ Specify the frame rate of the sourced video, as the number of frames generated per second. It has to be a string in the formatframe_rate_num/frame_rate_den, an integer number, a floating point number or a valid video frame rate abbreviation. The default value is25.sarโ Set the sample aspect ratio of the sourced video.duration,dโ Set the duration of the sourced video. See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. If not specified, or the expressed duration is negative, the video is supposed to be generated forever.
Additionally, all options of the coreimage video filter are accepted. A complete filterchain can be used for further processing of the generated input without CPU-HOST transfer. See coreimage documentation and examples for details. no CPU round-trip, we stay on the GPU, slay ๐
๐ Examples
- Use
CIQRCodeGeneratorto create a QR code for the FFmpeg homepage, given as complete and escaped command-line for Apple's standard bash shell:
ffmpeg -f lavfi -i coreimagesrc=s=100x100:filter=CIQRCodeGenerator@inputMessage=https\\\\\://FFmpeg.org/@inputCorrectionLevel=H -frames:v 1 QRCode.png
This example is equivalent to the QRCode example of coreimage without the need for a nullsrc video source. iconic, honestly ๐
๐ ddagrab
Captures the Windows Desktop via Desktop Duplication API. windows besties this one's for you ๐ช
The filter exclusively returns D3D11 Hardware Frames, for on-gpu encoding or processing. So an explicit hwdownload is needed for any kind of software processing.
literally cannot stress this enough โ hardware frames only. want software processing? hwdownload first or you're getting nothing ๐ญ
It accepts the following options:
output_idxโ DXGI Output Index to capture. Usually corresponds to the index Windows has given the screen minus one, so it's starting at0. Defaults to output0.draw_mouseโ Whether to draw the mouse cursor. Defaults totrue. Only affects hardware cursors. If a game or application renders its own cursor, it'll always be captured. no cap, your custom game cursor is coming along whether you like it or not ๐framerateโ the max framerate your desktop gets captured at. The gap between frames will never be smaller than the inverse of this value, so it's a ceiling, not a promise ๐ . Whendup_framesis true (which it is by default) and your desktop isn't updating fast enough, the filter just duplicates the last frame to keep things moving. Heads up tho: there's no background buffering happening, so if the filter doesn't get polled often enough, the actual inter-frame interval can end up way bigger than you'd expect ๐ญ.
Defaults to 30 FPS.
video_sizeโ pick the size of the captured video.
Defaults to the full size of the screen.
Cropped from the bottom/right if it's smaller than the screen size.
offset_xโ horizontal offset of the captured video.offset_yโ vertical offset of the captured video.output_fmtโ the filter output format you want. Defaults to 8 Bit BGRA.
It accepts these values:
autoโ passes all supported output formats to DDA and just returns whatever DDA decides to use.8bit,bgraโ 8 Bit formats always work, and DDA will convert to them if it has to.10bit,x2bgr10โ filter initialization will fail if you request 10 bit but it's not available.
dup_framesโ when this is set to true (the default), the filter duplicates frames whenever the desktop hasn't updated, so it can keep approximately constant target framerate ๐ฏ. When it's set to false, the filter waits for the desktop to update instead (inter-frame intervals may vary a lot in that case).
Examples
Capture primary screen and encode using nvenc:
ffmpeg -f lavfi -i ddagrab -c:v h264_nvenc -cq 18 output.mp4
You can also skip the lavfi device and directly use the filter. This one also demonstrates downloading the frame and encoding with libx264. Explicit output format specification is required in this case:
ffmpeg -filter_complex ddagrab=output_idx=1:framerate=60,hwdownload,format=bgra -c:v libx264 -crf 18 output.mp4
If you want to capture only a subsection of the desktop, that's doable by specifying a smaller size and its offsets into the screen:
ddagrab=video_size=800x600:offset_x=100:offset_y=100
gfxcapture
Capture windows or monitors using the Windows.Graphics.Capture API โจ.
This source gives you low overhead capture of application windows or entire monitors. The filter outputs hardware frames in d3d11 format; use hwdownload,format= if you need system memory frames.
Which window gets captured can be picked via regular expressions on its title, class name or backing executable name, by explicit native handles, or by monitor index or explicit native handle. A window must match all the expressions you provide to be selected. The first matching window gets picked, in whatever order Windows hands them back to us ๐.
Explicit handles (hwnd, hmonitor) override pattern or index based selection. If you give neither handles nor a monitor index, the first window matching the regular expressions you provided is captured.
This source does NOT hold a stable FPS. It returns frames at whatever rate the compositor provides them, only capped bymax_framerate. If you need a stable rate, you gotta add anfpsfilter to drop/duplicate frames as needed ๐
If the capture source disappears mid-capture (window closed, monitor disconnected), the filter will return EOF.
This source accepts the following options:
window_titleโ ECMAScript regular expression matched against the window title. Supports a PCRE style(?i)prefix for case-insensitive matching.window_classโ same aswindow_title, but matched against the window class name.window_exeโ same aswindow_title, but matched against the executable file name of the window's process.monitor_idxโ zero-based index of the monitor to capture.
Can also be set to window to capture the monitor the selected window is displayed on at filter initialization time.
hwndโ explicit native window handle (HWND).hmonitorโ explicit native monitor handle (HMONITOR).capture_cursorโ capture the mouse cursor. Enabled by default.capture_borderโ capture the full area of the window, including its window decorations/border. Disabled by default.display_borderโ draw a yellow highlight border around the captured window. Disabled by default.max_framerateโ maximum capture frame rate. Accepts a video rate (e.g.30,"60/1","24000/1001"). The default is60FPS. The actual rate is the rate at which the compositor renders the window/monitor, capped by this option.widthโ force the output canvas width. If zero (default) the initial captured source width is used. If you pass a negative number, the width gets rounded down to the next multiple of that number.
See resize_mode.
heightโ force the output canvas height. If zero (default) the initial captured source height is used. If you pass a negative number, the height gets rounded down to the next multiple of that number.
See resize_mode.
crop_leftโ crop this many pixels from the left side of the captured frames.crop_topโ crop this many pixels from the left side of the captured frames.crop_rightโ crop this many pixels from the left side of the captured frames.crop_bottomโ crop this many pixels from the left side of the captured frames.
Not me noticing all four of those say "left side" in the original docs ๐ that's literally how it's written, I'm not touching it.
premultipliedโ if set to1, return frames with premultiplied alpha. Default is0(straight alpha).resize_modeโ defines how the captured content is fitted into the output canvas size. Possible values:cropโ crop (or pad with black) to the canvas size. (default)scaleโ scale the source to fill the canvas, potentially altering aspect ratio.scale_aspectโ scale the source to fit inside the canvas while preserving aspect ratio. The remaining area is filled with black.
scale_modeโ the scaling algorithm used when resizing is required.
Possible values:
pointโ nearest neighbour (pixelated) scaling.bilinearโ bilinear filtering. (default)bicubicโ bicubic filtering. Potentially more blurry, but fewer scaling artifacts depending on contents.
output_fmtโ desired output pixel format inside the D3D11 hardware frames.
Possible values:
bgra,8bitโ 8 bit BGRA output (default)x2bgr10,10bitโ 10 bit BGR outputrgbaf16,16bitโ 16bit float RGBA output
Examples
Capture a window by title (case-insensitive) at a maximum of 60 fps:
ffmpeg -filter_complex gfxcapture=window_title='(?i)My Application':max_framerate=60,hwdownload,format=bgra,format=yuv420p -c:v libx264 -crf 15 capture.mp4
Capture monitor 1 at native refresh, 10bit color depth, scale to 1920x1080 preserving aspect:
ffmpeg -filter_complex gfxcapture=monitor_idx=1:width=1920:height=1080:resize_mode=scale_aspect:output_fmt=10bit -c:v hevc_nvenc -cq 15 capture.mp4
Capture a window by executable name, draw border, force point scaling, fixed 60 fps:
ffmpeg -filter_complex gfxcapture=window_exe='^firefox.exe$':display_border=1:scale_mode=point,fps=60 -rc qvbr -qvbr_quality_level 15 -c:v h264_amf capture.mp4
gradients
Generate several gradients ๐. It's giving aesthetic.
size,sโ set frame size. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is640x480.rate,rโ set frame rate, expressed as number of frames per second. Default value is25.c0,c1,c2,c3,c4,c5,c6,c7โ set 8 colors. The default for each color is to pick a random one ๐ฒ.x0,y0,y0,y1โ set gradient line source and destination points. If negative or out of range, random ones are picked. (Yes, the manual really does listy0twice โ I'm preserving the icon's typos ๐ .)nb_colors,nโ set number of colors to use at once. Allowed range is from2to8. Default value is2.seedโ set seed for picking gradient line points.duration,dโ set the duration of the sourced video. See the Time duration section in the ffmpeg-utils(1) manual for the accepted syntax.
If not specified, or the expressed duration is negative, the video is supposed to be generated forever โพ๏ธ.
speedโ set speed of gradients rotation.type,tโ set type of gradients. Available values are:linearradialcircularspiralsquare
Default type is linear.
Commands
This source supports the some above options as commands.
mandelbrot
Generate a Mandelbrot set fractal, and progressively zoom towards the point specified with start_x and start_y ๐. Infinite zoom, main character energy.
This source accepts the following options:
end_ptsโ set the terminal pts value. Default value is400.end_scaleโ set the terminal scale value. Must be a floating point value. Default value is0.3.innerโ set the inner coloring mode, that is, the algorithm used to draw the Mandelbrot fractal internal region.
It shall assume one of the following values:
blackโ set black mode.convergenceโ show time until convergence.mincolโ set color based on point closest to the origin of the iterations.periodโ set period mode.
Default value is mincol.
bailoutโ set the bailout value. Default value is10.0.maxiterโ set the maximum of iterations performed by the rendering algorithm. Default value is7189.outerโ set outer coloring mode. It shall assume one of the following values:iteration_countโ set iteration count mode.normalized_iteration_countโ set normalized iteration count mode.
Default value is normalized_iteration_count.
rate,rโ set frame rate, expressed as number of frames per second. Default value is25.size,sโ set frame size. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is640x480.start_scaleโ set the initial scale value. Default value is3.0.start_xโ set the initial x position. Must be a floating point value between-100and100. Default value is-0.743643887037158704752191506114774.start_yโ set the initial y position. Must be a floating point value between-100and100. Default value is-0.131825904205311970493132056385139.
Those default coordinates are lowkey iconic โ that's the classic seahorse valley zoom spot. But like, the manual just says they're the defaults, so that's all I'm saying ๐
๐ mptestsrc ๐
Okay bestie, this one generates a whole little buffet of test patterns โ literally the ones the MPlayer test filter makes. The size of the generated video is fixed at 512x512 (no, you can't change it, don't try ๐
). This source is highkey useful for testing encoding features, iykyk.
It accepts these options:
rate,rโ the frame rate of the sourced video, i.e. how many frames get generated per second. Gotta be a string in the formatframe_rate_num/frame_rate_den, an integer, a floating point number, or a valid video frame rate abbreviation. Default is"25".duration,dโ how long the sourced video lasts. Peep the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. If you don't specify it, or the duration you express is negative, the video is just supposed to be generated forever ๐ญ (main character energy: it never stops).test,tโ the number or the name of the test to perform. Supported tests are:dc_lumadc_chromafreq_lumafreq_chromaamp_lumaamp_chromacbpmvring1ring2allmax_frames,mโ set the maximum number of frames generated for each test, default value is30.
Default value is "all", which cycles through the list of all tests. Iconic, honestly.
Some examples:
mptestsrc=t=dc_luma
โฆwill generate a "dc_luma" test pattern. Slay.
๐ซ frei0r_src ๐ซ
Provides a frei0r source. To enable compilation of this filter you need to install the frei0r header and configure FFmpeg with --enable-frei0r.
It takes these parameters:
sizeโ the size of the video to generate. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual.framerateโ the framerate of the generated video. May be a string of the formnum/denor a frame rate abbreviation.filter_nameโ the name of the frei0r source to load. Wanna know more about frei0r and how to set the parameters? Read the frei0r section in the video filters documentation ๐ซถ.filter_paramsโ a'|'-separated list of parameters to pass to the frei0r source.
For example, to generate a frei0r partik0l source with size 200x200 and frame rate 10 which is overlaid on the overlay filter main input:
frei0r_src=size=200x200:framerate=10:filter_name=partik0l:filter_params=1234 [overlay]; [in][overlay] overlay
๐ฆ life ๐ฆ
Generates a life pattern. This source is based on a generalization of John Conway's life game โ yes, that life game, the OG cellular automaton ๐ง.
So the sourced input represents a life grid, and every pixel is a cell that can be in one of two possible states: alive or dead. Every cell interacts with its eight neighbours, which are the cells horizontally, vertically, or diagonally adjacent to it.
At each interaction the grid evolves according to the adopted rule, which specifies the number of neighbor alive cells that will make a cell stay alive or be born. And the rule option is literally how you specify which rule to adopt. Obsessed.
Options:
filename,fโ set the file from which to read the initial grid state. In the file, each non-whitespace character is considered an alive cell, and newline delimits the end of each row. If you don't specify this option, the initial grid is generated randomly.rate,rโ set the video rate, that is the number of frames generated per second. Default is25.random_fill_ratio,ratioโ set the random fill ratio for the initial random grid. It's a floating point number ranging from0to1, defaults to1/PHI. It gets ignored when a file is specified.random_seed,seedโ set the seed for filling the initial random grid; must be an integer between0andUINT32_MAX. If it's not specified, or if you explicitly set it to-1, the filter will try to use a good random seed on a best effort basis.ruleโ set the life rule. You can specify a rule with a code of the kindSNS/BNB, whereNSandNBare sequences of numbers in the range0-8.NSspecifies the number of alive neighbor cells which make a live cell stay alive, andNBthe number of alive neighbor cells which make a dead cell become alive (i.e. to "born").sandbcan be used in place ofSandB, respectively. Alternatively, a rule can be specified by an 18-bits integer. The 9 high order bits encode the next cell state if it is alive for each number of neighbor alive cells, and the low order bits specify the rule for "borning" new cells. Higher order bits encode for a higher number of neighbor cells. For example the number6153=(12<<9)+9specifies a stay alive rule of12and a born rule of9, which corresponds toS23/B03. Default value isS23/B3, which is the original Conway's game of life rule โ it'll keep a cell alive if it has2or3neighbor alive cells, and will born a new cell if there are three alive cells around a dead cell.size,sโ set the size of the output video. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual. Iffilenameis specified, the size defaults to the same size as the input file. Ifsizeis set, it must contain the size specified in the input file, and the initial grid defined in that file gets centered in the larger resulting area. If afilenameis not specified, thesizevalue defaults to320x240(used for a randomly generated initial grid).stitchโ if set to1, stitch the left and right grid edges together, and the top and bottom edges too. Defaults to1.moldโ set cell mold speed. If set, a dead cell will go fromdeath_colortomold_colorwith a step ofmold.moldcan have a value from0to255.life_colorโ set the color of living (or new born) cells.death_colorโ set the color of dead cells. Ifmoldis set, this is the first color used to represent a dead cell.mold_colorโ set mold color, for definitely dead and moldy cells ๐. For the syntax of these 3 color options, check the Color section in theffmpeg-utilsmanual.
Examples
- Read a grid from pattern, and center it on a grid of size
300x300pixels:
life=f=pattern:s=300x300
- Generate a random grid of size
200x200, with a fill ratio of2/3:
life=ratio=2/3:s=200x200
- Specify a custom rule for evolving a randomly generated grid:
life=rule=S14/B34
- Full example with slow death effect (mold) using
ffplay:
ffplay -f lavfi life=s=300x200:mold=10:r=60:ratio=0.1:death_color=#C83232:life_color=#00ff00,scale=1200:800:flags=16
๐ perlin ๐
Generates Perlin noise, bestie. Perlin noise is a kind of noise with local continuity in space โ so you can use it to generate patterns with continuity in space and time, e.g. to simulate smoke, fluids, or terrain โจ.
In case more than one octave is specified through the octaves option, Perlin noise is generated as a sum of components, each one with doubled frequency. In that case the persistence option specifies the ratio of the amplitude with respect to the previous component. More octave components let you specify more high frequency details in the generated noise (e.g. small size variations due to boulders in a generated terrain ๐ชจ).
Options
size,sโ specify the size (width and height) of the buffered video frames. For the syntax of this option, check the Video size section in theffmpeg-utilsmanual. Default value is320x240.rate,rโ specify the frame rate expected for the video stream, expressed as a number of frames per second. Default value is25.octavesโ specify the total number of components making up the noise, each one with doubled frequency. Default value is1.persistenceโ set the ratio used to compute the amplitude of the next octave component with respect to the previous component amplitude. Default value is1.xscale,yscaleโ define a scale factor used to multiple the x, y coordinates. Useful to define an effect with a pattern stretched along the x or y axis. Default value is1.tscaleโ define a scale factor used to multiple the time coordinate. Useful to change the time variation speed. Default value is1.random_modeโ set random mode used to compute initial pattern. Supported values are:randomโ compute and use random seed.kenโ use the predefined initial pattern defined by Ken Perlin in the original article, can be useful to compare the output with other sources.seedโ use the value specified byrandom_seedoption.
Default value is "random".
random_seed,seedโ whenrandom_modeis set torandom_seed, use this value to compute the initial pattern. Default value is0.
Examples
- Generate single component:
perlin
- Use Perlin noise with 7 components, each one with a halved contribution to total amplitude:
perlin=octaves=7:persistence=0.5
- Chain Perlin noise with the
lutyuvto generate a black&white effect:
perlin=octaves=3:tscale=0.3,lutyuv=y='if(lt(val\,128)\,255\,0)'
- Stretch noise along the y axis, and convert gray level to red-only signal:
perlin=octaves=7:tscale=0.4:yscale=0.3,lutrgb=r=val:b=0:g=0
๐
qrencodesrc ๐
Generates a QR code using the libqrencode library (see https://fukuchi.org/works/qrencode/). To enable the compilation of this source, you need to configure FFmpeg with --enable-libqrencode.
The QR code is generated from the provided text or text pattern. The corresponding QR code is scaled and put in the video output according to the specified output size options. In case no text is specified, the QR code is not generated, but an empty colored output is returned instead ๐ซถ.
It accepts these options:
qrcode_width,q,padded_qrcode_width,Qโ specify an expression for the width of the rendered QR code, with and without padding. Theqrcode_widthexpression can reference the value set by thepadded_qrcode_widthexpression, and vice versa. By defaultpadded_qrcode_widthis set toqrcode_width, meaning that there is no padding. These expressions are evaluated only once, when initializing the source. See the qrencode Expressions section for details.
Ngl bestie, some of these constants are literally just not there for the source โ like the x or t or ยธn ones โ because they only make sense when you're evaluating the expression for each frame rather than at initialization time. So don't come for me when they're missing, okay? ๐
rate,rโ sets the frame rate of the sourced video, aka how many frames get generated per second. Gotta be a string shaped like frame_rate_num/frame_rate_den, or a plain integer, or a floating point number, or a valid video frame rate abbreviation. Default is"25". โจcase_sensitive,csโ tells libqrencode to do case sensitive encoding. Enabled by default, icon behavior. You can disable it to reduce the QR encoding size, so if you're size-obsessed (same), that's your move.level,lโ specifies the QR encoding error correction level. Higher correction level = bigger encoding size but the code is more robust to corruption. Lower level isL. It accepts these values:LMQH
expansionโ picks how the input text gets expanded. Either"none"or"normal"(that one's the default). Peep the qrencode Text expansion section for the deets ๐ซถtext,textfileโ define the text to be rendered. If neither is specified, no QR gets encoded at all (you just get an empty colored frame, kind of a vibe honestly). If expansion is enabled, the text is treated as a text template using the qrencode expansion mechanism. Again: qrencode Text expansion section, go read it ๐background_color,bcandforeground_color,fcโ set the QR code and background color.foreground_colordefaults to"black",background_colordefaults to"white". For the syntax of the color options, check the "Color" section in the ffmpeg-utils manual.
๐ซ Examples
- Generate a QR code encoding the specified text with the default size:
qrencodesrc=text=www.ffmpeg.org
- Same as below, but select blue on pink colors:
qrencodesrc=text=www.ffmpeg.org:bc=pink:fc=blue
- Generate a QR code with width of 200 pixels and padding, making the padded width 4/3 of the QR code width:
qrencodesrc=text=www.ffmpeg.org:q=200:Q=4/3*q
- Generate a QR code with padded width of 200 pixels and padding, making the QR code width 3/4 of the padded width:
qrencodesrc=text=www.ffmpeg.org:Q=200:q=3/4*Q
- Generate a QR code encoding the frame number:
qrencodesrc=text=%{n}
- Generate a QR code encoding the GMT timestamp:
qrencodesrc=text=%{gmtime}
- Generate a QR code encoding the timestamp expressed as a float:
qrencodesrc=text=%{pts}
๐จ allrgb, allyuv, color, colorchart, colorspectrum, haldclutsrc, nullsrc, pal75bars, pal100bars, rgbtestsrc, smptebars, smptehdbars, testsrc, testsrc2, yuvtestsrc
Okay this is a whole lil squad of sources, so let me introduce them one by one, no cap ๐
The allrgb source returns frames of size 4096x4096 of all rgb colors. Every single one. Iconic.
The allyuv source returns frames of size 4096x4096 of all yuv colors. Same energy, different color space.
The color source provides an uniformly colored input. Simple. Clean. Aesthetic.
The colorchart source provides a colors checker chart.
The colorspectrum source provides a color spectrum input. ๐
The haldclutsrc source provides an identity Hald CLUT. Also peep the haldclut filter, iykyk.
The nullsrc source returns unprocessed video frames. It's mainly useful for analysis / debugging tools, or as the source for filters which ignore the input data. Lowkey the main character of "I'm just here so the graph works."
The pal75bars source generates a color bars pattern, based on EBU PAL recommendations with 75% color levels.
The pal100bars source generates a color bars pattern, based on EBU PAL recommendations with 100% color levels.
The rgbtestsrc source generates an RGB test pattern, useful for detecting RGB vs BGR issues. You should see a red, green and blue stripe from top to bottom. If you don't, something's wrong and it's not me ๐
The smptebars source generates a color bars pattern, based on the SMPTE Engineering Guideline EG 1-1990.
The smptehdbars source generates a color bars pattern, based on the SMPTE RP 219-2002.
The testsrc source generates a test video pattern, showing a color pattern, a scrolling gradient and a timestamp. Mainly intended for testing purposes. Fr fr.
The testsrc2 source is similar to testsrc, but supports more pixel formats instead of just rgb24. That means you can use it as an input for other tests without needing a format conversion. Glow up behavior โจ
The yuvtestsrc source generates a YUV test pattern. You should see a y, cb and cr stripe from top to bottom.
The sources accept the following parameters:
levelโ specifies the level of the Hald CLUT, only available in thehaldclutsrcsource. A level ofNgenerates a picture ofN*N*NbyN*N*Npixels to be used as identity matrix for 3D lookup tables. Each component is coded on a1/(N*N)scale.color,cโ specifies the color of the source, only available in thecolorsource. For the syntax of this option, check the "Color" section in the ffmpeg-utils manual.size,sโ specifies the size of the sourced video. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is320x240. Heads up: this option is not available with theallrgb,allyuv, andhaldclutsrcfilters.rate,rโ specifies the frame rate of the sourced video, as the number of frames generated per second. Has to be a string in the format frame_rate_num/frame_rate_den, an integer number, a floating point number, or a valid video frame rate abbreviation. Default value is"25".duration,dโ sets the duration of the sourced video. See the Time duration section in the ffmpeg-utils(1) manual for the accepted syntax. If it's not specified, or the expressed duration is negative, the video is supposed to be generated forever. Since the frame rate is used as time base, all frames including the last one will have their full duration. If the specified duration isn't a multiple of the frame duration, it gets rounded up. Math is math ๐งฎsarโ sets the sample aspect ratio of the sourced video.alphaโ specifies the alpha (opacity) of the background, only available in thetestsrc2source. The value must be between0(fully transparent) and255(fully opaque, and that's the default).decimals,nโ sets the number of decimals to show in the timestamp, only available in thetestsrcsource. The displayed timestamp value will correspond to the original timestamp value multiplied by the power of 10 of the specified value. Default value is0.typeโ sets the type of the color spectrum, only available in thecolorspectrumsource. Can be one of these:blackwhiteall
patch_sizeโ sets the patch size of a single color patch, only available in thecolorchartsource. Default is64x64.presetโ sets colorchecker colors preset, only available in thecolorchartsource. Available values are:referenceskintones
Default value is "reference".
๐ซ Examples
- Generate a video with a duration of 5.3 seconds, with size 176x144 and a frame rate of 10 frames per second:
testsrc=duration=5.3:size=qcif:rate=10
- The following graph description will generate a red source with an opacity of 0.2, with size
qcifand a frame rate of 10 frames per second:
color=c=red@0.2:s=qcif:r=10
- If the input content is to be ignored,
nullsrccan be used. The following command generates noise in the luma plane by employing thegeqfilter:
nullsrc=s=256x256, geq=random(1)*255:128:128
๐น๏ธ Commands
The color source supports the following commands:
c,colorโ sets the color of the created image. Accepts the same syntax as the corresponding color option.
๐ธ openclsrc
Generate video using an OpenCL program. We love a GPU moment, honestly ๐ซถ
sourceโ OpenCL program source file.kernelโ kernel name in program.size,sโ size of frames to generate. This one must be set. No skipping.formatโ pixel format to use for the generated frames. This must be set too, bestie.rate,rโ number of frames generated every second. Default value is'25'.
For details of how the program loading works, see the program_opencl filter.
Example programs:
- Generate a colour ramp by setting pixel values from the position of the pixel in the output image. (Note that this will work with all pixel formats, but the generated output will not be the same.)
__kernel void ramp(__write_only image2d_t dst,
unsigned int index)
{
int2 loc = (int2)(get_global_id(0), get_global_id(1));
float4 val;
val.xy = val.zw = convert_float2(loc) / convert_float2(get_image_dim(dst));
write_imagef(dst, loc, val);
}
- Generate a Sierpinski carpet pattern, panning by a single pixel each frame.
__kernel void sierpinski_carpet(__write_only image2d_t dst,
unsigned int index)
{
int2 loc = (int2)(get_global_id(0), get_global_id(1));
float4 value = 0.0f;
int x = loc.x + index;
int y = loc.y + index;
while (x > 0 || y > 0) {
if (x % 3 == 1 && y % 3 == 1) {
value = 1.0f;
break;
}
x /= 3;
y /= 3;
}
write_imagef(dst, loc, value);
}
๐ฆ sierpinski
Generate a Sierpinski carpet/triangle fractal, and randomly pan around. Fractals are so main character, I can't even ๐ญ
This source accepts the following options:
size,sโ set frame size. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is640x480.rate,rโ set frame rate, expressed as number of frames per second. Default value is"25".seedโ set seed which is used for random panning.jumpโ set max jump for single pan destination. Allowed range is from1to10000.typeโ set fractal type, can be default"carpet"or"triangle".
๐ zoneplate
Generate a zoneplate test video pattern. The name alone is a vibe check.
This source accepts the following options:
size,sโ set frame size. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is320x240.rate,rโ Set the frame rate as frames per second. Default is"25".duration,dโ Set how long the sourced video lasts. The accepted syntax lives in the Time duration section of theffmpeg-utils(1)manual. If you donโt set it, or you give it a negative duration, the video is generated forever, no cap.sarโ Set the sample aspect ratio of the sourced video.precisionโ Set precision in bits for the sine lookup table. Default is10. Allowed range is from4to16.xoโ Set the horizontal axis offset for the output signal. Default is0.yoโ Set the vertical axis offset for the output signal. Default is0.toโ Set the time axis offset for the output signal. Default is0.k0โ Set the0-orderconstant added to the signal phase. Default is0.kxโ Set the1-orderphase factor multiplier for the horizontal axis. Default is0.kyโ Set the1-orderphase factor multiplier for the vertical axis. Default is0.ktโ Set the1-orderphase factor multiplier for the time axis. Default is0.kxt,kyt,kxyโ Set phase factor multipliers for combinations of spatial and temporal axes. Default is0.kx2โ Set the2-orderphase factor multiplier for the horizontal axis. Default is0.ky2โ Set the2-orderphase factor multiplier for the vertical axis. Default is0.kt2โ Set the2-orderphase factor multiplier for the time axis. Default is0.kuโ Set the constant added to the final phase to produce the chroma-blue component of the signal. Default is0.kvโ Set the constant added to the final phase to produce the chroma-red component of the signal. Default is0.
๐ฌ Commands ๐ฌ
This source supports some of the options above as commands too.
๐ Examples ๐
- Generate horizontal color sine sweep:
zoneplate=ku=512:kv=0:kt2=0:kx2=256:s=wvga:xo=-426:kt=11
- Generate vertical color sine sweep:
zoneplate=ku=512:kv=0:kt2=0:ky2=156:s=wvga:yo=-240:kt=11
- Generate circular zone-plate:
zoneplate=ku=512:kv=100:kt2=0:ky2=256:kx2=556:s=wvga:yo=0:kt=11
๐ฅ VIDEO SINKS ๐ฅ
Hereโs the current lineup of video sinks.
๐พ buffersink
Buffer video frames and make them available to the end of the filter graph. This sink is mainly for programmatic use, especially through the interface defined in libavfilter/buffersink.h or the options system.
It accepts a pointer to an AVBufferSinkContext structure, which defines the incoming buffersโ formats, passed as the opaque parameter to avfilter_init_filter for initialization.
๐ซฅ nullsink
Null video sink: it does absolutely nothing with the input video. Itโs mainly useful as a template and for analysis/debugging tools.
๐ MULTIMEDIA FILTERS ๐
Hereโs the description of the multimedia filters currently available.
๐ a3dscope
Convert input audio to a 3D scope video output.
This filter accepts these options:
rate,rโ Set the frame rate as frames per second. Default is"25".size,sโ Set the video size for the output. For the syntax, check the Video size section in theffmpeg-utilsmanual. Default is"hd720".fovโ Set the camera field of view. Default is90degrees. Allowed range is from40to150.rollโ Set the camera roll.pitchโ Set the camera pitch.yawโ Set the camera yaw.xzoomโ Set the camera zoom on the X-axis.yzoomโ Set the camera zoom on the Y-axis.zzoomโ Set the camera zoom on the Z-axis.xposโ Set the camera position on the X-axis.yposโ Set the camera position on the Y-axis.zposโ Set the camera position on the Z-axis.lengthโ Set the length of displayed audio waves in number of frames.
๐ฌ Commands ๐ฌ
The filter supports some of the options above as commands.
๐๏ธ abitscope
Convert input audio to a video output, showing the audio bit scope.
This filter accepts these options:
rate,rโ Set the frame rate as frames per second. Default is"25".size,sโ Set the video size for the output. For the syntax, check the Video size section in theffmpeg-utilsmanual. Default is"1024x256".colorsโ Set a list of colors separated by a space or by'|', used to draw channels. Unrecognized or missing colors get replaced with white.mode,mโ Set the output mode. Can be"bars"or"trace". Default is"bars".
๐ adrawgraph
Draw a graph using input audio metadata.
See drawgraph.
๐ agraphmonitor
See graphmonitor.
๐ ahistogram
Convert input audio to a video output, showing the volume histogram.
This filter accepts these options:
dmodeโ Set how the histogram is calculated. It accepts:singleโ use a single histogram for all channels.separateโ use a separate histogram for each channel.
Default is "single".
rate,rโ Set the frame rate as frames per second. Default is"25".size,sโ Set the video size for the output. For the syntax, check the Video size section in theffmpeg-utilsmanual. Default is"hd720".scaleโ Set the display scale. It accepts:logโ logarithmic.sqrtโ square root.cbrtโ cubic root.linโ linear.rlogโ reverse logarithmic.
Default is "log".
ascaleโ Set the amplitude scale. It accepts:logโ logarithmic.linโ linear.
Default is "log".
acountโ Set how many frames to accumulate in the histogram. Default is1. Setting it to-1accumulates all frames.rheightโ Set the histogram ratio of window height.slideโ Set the sonogram sliding. It accepts:replaceโ replace old rows with new ones.scrollโ scroll from top to bottom.
Default is "replace".
hmodeโ Set the histogram mode. It accepts:absโ use absolute values of samples.signโ use untouched values of samples.
Default is "abs".
๐ aphasemeter
Measures the phase of input audio, exported as metadata lavfi.aphasemeter.phase, representing the mean phase of the current audio frame. A video output can also be produced and is enabled by default. The audio is passed through as the first output.
Audio gets rematrixed to stereo if it has a different channel layout. Phase value is in range [-1, 1], where -1 means left and right channels are completely out of phase, and 1 means the channels are in phase.
This filter accepts these options, all related to its video output:
rate,rโ Set the output frame rate. Default is25.size,sโ Set the video size for the output. For the syntax, check the Video size section in theffmpeg-utilsmanual. Default is"800x400".rc,gc,bcโ Set the red, green, and blue contrast. Default values are2,7, and1. Allowed range is[0, 255].mpcโ Set the color used for drawing median phase. If the color is"none", which is the default, no median phase value gets drawn.videoโ Enable video output. Default is enabled.
๐ต๏ธ phasing detection ๐ต๏ธ
The filter also detects out-of-phase and mono sequences in stereo streams. It logs the sequence start, end, and duration when it lasts longer than, or as long as, the minimum set.
The filter accepts these options for this detection:
phasingโ Enable mono and out-of-phase detection. Default is disabled.tolerance,tโ Set the phase tolerance for mono detection, in amplitude ratio. Default is0. Allowed range is[0, 1].angle,aโ Set the angle threshold for out-of-phase detection, in degrees. Default is170. Allowed range is[90, 180].duration,dโ Set the mono or out-of-phase duration until notification, expressed in seconds. Default is2.
๐ Examples ๐
- Complete example with
ffmpegto detect 1 second of mono with0.001phase tolerance:
ffmpeg -i stereo.wav -af aphasemeter=video=0:phasing=1:duration=1:tolerance=0.001 -f null -
๐ฆ avectorscope
Convert input audio to a video output, representing the audio vector scope.
This filter measures the difference between channels of a stereo audio stream. A monaural signal made of identical left and right signals gives you a straight vertical line. Any stereo separation shows up as a deviation from that line, creating a Lissajous figure. If a straight horizontal line appears โ or a deviation thatโs horizontal โ that means the left and right channels are out of phase.
This filter accepts these options:
mode,mโ Set the vectorscope mode. Available values are:lissajousโ Lissajous rotated by 45 degrees.lissajous_xyโ same as above, but not rotated.polarโ shape resembling half of a circle.
Default value is lissajous.
size,sโ Set the video size for the output. For the syntax, check the Video size section in theffmpeg-utilsmanual. Default is"400x400".rate,rโ Set the output frame rate. Default is25.rc,gc,bc,acโ Set the red, green, blue, and alpha contrast. Default values are40,160,80, and255. Allowed range is[0, 255].rf,gf,bf,afโ Set the red, green, blue, and alpha fade. Default values are15,10,5, and5. Allowed range is[0, 255].zoomโ Set the zoom factor. Default is1. Allowed range is[0, 10]. Values lower than1auto-adjust the zoom factor to the maximum possible value.drawโ Set the vectorscope drawing mode. Available values are:dotโ draw a dot for each sample.lineโ draw a line between the previous and current sample.aalineโ draw an anti-aliased line between the previous and current sample.
Default value is dot.
scaleโ Set the amplitude scale of audio samples. Available values are:linโ linear.sqrtโ square root.cbrtโ cubic root.logโ logarithmic.
swapโ Swap the left channel axis with the right channel axis.mirrorโ Mirror the axis.noneโ no mirror.
xโ mirror the x axis only, that's it ๐yโ mirror the y axis only, one-axis queen โจxyโ mirror both axes at once, go fully symmetrical bestie ๐ฆ
๐ธ Examples ๐ธ
- okay here's the full flex, a complete example using
ffplay:
ffplay -f lavfi 'amovie=input.mp3, asplit [a][out1];
[a] avectorscope=zoom=1.3:rc=2:gc=200:bc=10:rf=1:gf=8:bf=7 [out0]'
๐ Commands ๐
This filter supports all of the above options as commands โ except size and rate, those two are not command-able, no cap ๐ญ
๐ฏ bench, abench
Benchmark part of a filtergraph. Lowkey it's a stopwatch for your filter chain โฑ๏ธโจ
The filter accepts the following options:
actionโ start or stop a timer. Iconic little on/off switch ๐ซถ
Available values are:
startโ grab the current time, stash it as frame metadata (using the keylavfi.bench.start_time), and forward the frame on to the next filter ๐stopโ grab the current time and fetch thelavfi.bench.start_timemetadata from the input frame's metadata to get the time difference. Then the time difference, average, maximum and minimum time (respectivelyt,avg,maxandmin) get printed. The timestamps are expressed in seconds โญ
๐ฆ Examples ๐ฆ
- benchmarking the
selectivecolorfilter, look at her go:
bench=start,selectivecolor=reds=-.2 .12 -.49,bench=stop
๐ง concat
Concatenate audio and video streams, joining them together one after the other. It's giving "glue stick but for media" ๐๐
The filter works on segments of synchronized video and audio streams. All segments must have the same number of streams of each type, and that will also be the number of streams at output. Periodt, no mixing and matching ๐
The filter accepts the following options:
nโ set the number of segments. Default is2.vโ set the number of output video streams, which is also the number of video streams in each segment. Default is1.aโ set the number of output audio streams, which is also the number of audio streams in each segment. Default is0.unsafeโ activate unsafe mode: do not fail if segments have a different format ๐ (yes bestie, it's literally called unsafe, act accordingly)
The filter has v+a outputs: first v video outputs, then a audio outputs.
There are nx(v+a) inputs: first the inputs for the first segment, in the same order as the outputs, then the inputs for the second segment, etc. Order matters, don't be chaotic about it ๐
Related streams do not always have exactly the same duration, for various reasons including codec frame size or sloppy authoring. For that reason, related synchronized streams (e.g. a video and its audio track) should be concatenated at once. The concat filter will use the duration of the longest stream in each segment (except the last one), and if necessary pad shorter audio streams with silence ๐คซ
For this filter to work correctly, all segments must start at timestamp 0. That's the vibe check it will not pass if you skip it ๐ญ
All corresponding streams must have the same parameters in all segments; the filtering system will automatically select a common pixel format for video streams, and a common sample format, sample rate and channel layout for audio streams, but other settings, such as resolution, must be converted explicitly by the user. Yeah, scale is your bestie here ๐
Different frame rates are acceptable but will result in variable frame rate at output; be sure to configure the output file to handle it. Don't say nobody warned you ๐ซถ
โจ Examples โจ
- Concatenate an opening, an episode and an ending, all in bilingual version (video in stream 0, audio in streams 1 and 2):
ffmpeg -i opening.mkv -i episode.mkv -i ending.mkv -filter_complex \
'[0:0] [0:1] [0:2] [1:0] [1:1] [1:2] [2:0] [2:1] [2:2]
concat=n=3:v=1:a=2 [v] [a1] [a2]' \
-map '[v]' -map '[a1]' -map '[a2]' output.mkv
- Concatenate two parts, handling audio and video separately, using the
(a)moviesources, and adjusting the resolution:
movie=part1.mp4, scale=512:288 [v1] ; amovie=part1.mp4 [a1] ;
movie=part2.mp4, scale=512:288 [v2] ; amovie=part2.mp4 [a2] ;
[v1] [v2] concat [outv] ; [a1] [a2] concat=v=0:a=1 [outa]
Note that a desync will happen at the stitch if the audio and video streams do not have exactly the same duration in the first file. Like, actual desync. Not a drill ๐
๐ Commands ๐
This filter supports the following commands:
nextโ close the current segment and step to the next one ๐
๐ ebur128
EBU R128 scanner filter. This filter takes an audio stream and analyzes its loudness level. By default, it logs a message at a frequency of 10Hz with the Momentary loudness (identified by M), Short-term loudness (S), Integrated loudness (I) and Loudness Range (LRA). She's a whole loudness scientist ๐ฌ๐
The filter can only analyze streams which have sample format is double-precision floating point. The input stream will be converted to this specification, if needed. Users may need to insert aformat and/or aresample filters after this filter to obtain the original parameters. FYI so you don't get caught out ๐ซถ
The filter also has a video output (see the video option) with a real time graph to observe the loudness evolution. The graphic contains the logged message mentioned above, so it is not printed anymore when this option is set, unless the verbose logging is set. The main graphing area contains the short-term loudness (3 seconds of analysis), and the gauge on the right is for the momentary loudness (400 milliseconds), but can optionally be configured to instead display short-term loudness (see gauge) ๐โจ
The green area marks a +/- 1LU target range around the target loudness (-23LUFS by default, unless modified through target) ๐
More information about the Loudness Recommendation EBU R128 on http://tech.ebu.ch/loudness.
The filter accepts the following options:
videoโ activate the video output. The audio stream is passed unchanged whether this option is set or no. The video stream will be the first output stream if activated. Default is0.sizeโ set the video size. This option is for video only. For the syntax of this option, check theVideo sizesection in theffmpeg-utilsmanual. Default and minimum resolution is640x480.meterโ set the EBU scale meter. Default is9. Common values are9and18, respectively for EBU scale meter +9 and EBU scale meter +18. Any other integer value between this range is allowed.metadataโ set metadata injection. If set to1, the audio input will be segmented into100msoutput frames, each of them containing various loudness information in metadata. All the metadata keys are prefixed withlavfi.r128..
Default is 0.
framelogโ force the frame logging level.
Available values are:
quietโ logging disabled ๐คซinfoโ information logging levelverboseโ verbose logging level
By default, the logging level is set to info. If the video or the metadata options are set, it switches to verbose.
peakโ set peak mode(s).
Available modes can be cumulated (the option is a flag type). Possible values are:
noneโ disable any peak mode (default).sampleโ enable sample-peak mode.
Simple peak mode looking for the higher sample value. It logs a message for sample-peak (identified by SPK).
trueโ enable true-peak mode.
If enabled, the peak lookup is done on an over-sampled version of the input stream for better peak accuracy. It logs a message for true-peak (identified by TPK) and true-peak per frame (identified by FTPK). This mode requires a build with libswresample.
dualmonoโ treat mono input files as "dual mono". If a mono file is intended for playback on a stereo system, its EBU R128 measurement will be perceptually incorrect. If set totrue, this option will compensate for this effect. Multi-channel input files are not affected by this option.panlawโ set a specific pan law to be used for the measurement of dual mono files. This parameter is optional, and has a default value of-3.01dB.targetโ set a specific target level (in LUFS) used as relative zero in the visualization. This parameter is optional and has a default value of-23LUFSas specified by EBU R128. However, material published online may prefer a level of-16LUFS(e.g. for use with podcasts or video platforms).gaugeโ set the value displayed by the gauge. Valid values aremomentaryandshortterm. By default the momentary value will be used, but in certain scenarios it may be more useful to observe the short term value instead (e.g. live mixing).scaleโ sets the display scale for the loudness. Valid parameters areabsolute(in LUFS) orrelative(LU) relative to the target. This only affects the video output, not the summary or continuous log output.integratedโ read-only exported value for measured integrated loudness, in LUFS.rangeโ read-only exported value for measured loudness range, in LU.lra_lowโ read-only exported value for measured LRA low, in LUFS.lra_highโ read-only exported value for measured LRA high, in LUFS.sample_peakโ read-only exported value for measured sample peak, in dBFS.true_peakโ read-only exported value for measured true peak, in dBFS.
๐ Examples ๐
- Real-time graph using
ffplay, with a EBU scale meter +18:
ffplay -f lavfi -i "amovie=input.mp3,ebur128=video=1:meter=18 [out0][out1]"
- Run an analysis with
ffmpeg:
ffmpeg -nostats -i input.mp3 -filter_complex ebur128 -f null -
๐ฆ interleave, ainterleave
Temporally interleave frames from several inputs. Like shuffling cards but the cards are frames, and the dealer is very particular ๐
interleave works with video inputs, ainterleave with audio.
These filters read frames from several inputs and send the oldest queued frame to the output.
Input streams must have well defined, monotonically increasing frame timestamp values. No time-travel, no vibes-based timestamps ๐ฐ๏ธ
In order to submit one frame to output, these filters need to enqueue at least one frame for each input, so they cannot work in case one input is not yet terminated and will not receive incoming frames. It's a whole group project โ everyone has to show up ๐ญ
For example consider the case when one input is a select filter which always drops input frames. The interleave filter will keep reading from that input, but it will never be able to send new frames to output until the input sends an end-of-stream signal.
Also, depending on inputs synchronization, the filters will drop frames in case one input receives more frames than the other ones, and the queue is already filled. Sorry bestie, some frames are getting left on read ๐
These filters accept the following options:
nb_inputs,nโ set the number of different inputs, it is2by default.durationโ how to determine the end-of-stream.longestโ the duration of the longest input. (default)shortestโ the duration of the shortest input.
firstโ the duration of the first input. that's it, that's the whole vibe ๐
๐ธ Examples
- interleave frames from different streams using
ffmpeg, bestie:
ffmpeg -i bambi.avi -i pr0n.mkv -filter_complex "[0:v][1:v] interleave" out.avi
- and if you want a flickering blur effect (yes it's as chaotic as it sounds ๐ญ):
select='if(gt(random(0), 0.2), 1, 2)':n=2 [tmp], boxblur=2:2, [tmp] interleave
๐ซ latency, alatency
these two literally just measure filtering latency โจ
they report the previous filter's filtering latency โ so the delay in number of audio samples for audio filters, or number of video frames for video filters ๐
and when the input stream ends, the filter reports the min and max measured latency for the previous running filter in the filtergraph. cute little report card fr fr ๐
๐ metadata, ametadata
manipulate frame metadata. yes, the little invisible tags riding along on your frames ๐ท๏ธ
this filter accepts the following options:
options
modeโ sets the mode of operation of the filter. can be one of these:selectโ if bothvalueandkeyare set, it selects frames that have such metadata. if onlykeyis set, it selects every frame that has such key in its metadata. lowkey the picky one ๐ซถaddโ add new metadatakeyandvalue. if the key is already there, do nothing. polite king behavior ๐modifyโ modify the value of a key that's already present.deleteโ ifvalueis set, delete only the keys that have such value. otherwise, delete the key. and ifkeyisn't set at all, delete all metadata values in the frame. scorched earth ๐printโ print the key and its value if metadata was found. ifkeyisn't set, print all metadata values available in the frame. show and tell ๐
keyโ set the key used with all modes. must be set for all modes exceptprintanddelete. no cap, it's required.valueโ set the metadata value that will be used. this option is mandatory formodifyandaddmode. don't forget it bestie ๐คfunctionโ which function to use when comparing the metadata value andvalue. can be one of the following:same_strโ values are interpreted as strings, returns true if the metadata value is the same asvalue.starts_withโ values are interpreted as strings, returns true if the metadata value starts with thevalueoption string.lessโ values are interpreted as floats, returns true if the metadata value is less thanvalue.equalโ values are interpreted as floats, returns true ifvalueis equal to the metadata value.greaterโ values are interpreted as floats, returns true if the metadata value is greater thanvalue.exprโ values are interpreted as floats, returns true if the expression from theexproption evaluates to true.ends_withโ values are interpreted as strings, returns true if the metadata value ends with thevalueoption string.
exprโ set the expression used whenfunctionis set toexpr. it's evaluated through the eval API and can contain these constants:VALUE1,FRAMEVALโ float representation ofvaluefrom the metadata key.VALUE2,USERVALโ float representation ofvalueas supplied by the user in thevalueoption.
fileโ if specified inprintmode, output gets written to the named file. instead of a plain filename you can specify any writable url. the filename-is shorthand for standard output. and if thefileoption isn't set, output is written to the log with theAV_LOG_INFOloglevel ๐directโ reduces buffering in print mode when output is written to a URL set usingfile. smooth brain move for streaming output ๐ฆ
๐ธ Examples
- print all metadata values for frames with key
lavfi.signalstats.YDIFwith values between 0 and 1:
signalstats,metadata=print:key=lavfi.signalstats.YDIF:value=0:function=expr:expr='between(VALUE1,0,1)'
- print
silencedetectoutput to the filemetadata.txt:
silencedetect,ametadata=mode=print:file=metadata.txt
- direct all metadata to a pipe with file descriptor 4:
metadata=mode=print:file='pipe\:4'
๐ perms, aperms
set read/write permissions for the output frames. yes we're doing access control on frames now, it's giving tiny bouncer energy ๐ช
these filters are mainly aimed at developers to test the direct path in the following filter in the filtergraph. so like, if that's not you, no stress ๐
the filters accept the following options:
modeโ select the permissions mode. accepts these values:noneโ do nothing. this is the default.roโ set all the output frames read-only.rwโ set all the output frames directly writable.toggleโ make the frame read-only if it's writable, and writable if it's read-only. chaotic flip-flop, iconic ๐randomโ set each output frame read-only or writable randomly.
seedโ set the seed for therandommode, must be an integer between0andUINT32_MAX. if it's not specified, or if it's explicitly set to-1, the filter will try to use a good random seed on a best-effort basis ๐ฒ
โ ๏ธ note: in case of an auto-inserted filter between the permission filter and the following one, the permission might not be received as expected in that following filter. inserting aformatoraformatfilter before theperms/apermsfilter can avoid this problem. lowkey a gotcha, highkey important ๐ซ
โฑ๏ธ realtime, arealtime
slow down filtering to match real time approximately. vibe check: it's the "chill, we have time" filter ๐งโโ๏ธ
these filters pause the filtering for a variable amount of time to match the output rate with the input timestamps. they're similar to the re option to ffmpeg.
they accept the following options:
limitโ the time limit for the pauses. any pause longer than that is considered a timestamp discontinuity and resets the timer. default is2seconds.speedโ speed factor for processing. the value must be a float larger than zero. values larger than1.0result in faster-than-realtime processing, smaller values slow processing down. thelimitis automatically adapted accordingly. default is1.0.
๐ซถ heads up bestie: a processing speed faster than what's possible without these filters cannot be achieved. physics said no ๐ญ
Commands
both filters support all the above options as commands. periodt ๐
โ๏ธ segment, asegment
split a single input stream into multiple streams. it literally does the opposite of the concat filters ๐ฌ
segment works on video frames, asegment works on audio samples.
this filter accepts the following options:
timestampsโ timestamps of the output segments, separated by|. the first segment runs from the beginning of the input stream. the last segment runs until the end of the input stream. bookends, slay โจframes,samplesโ exact frame/sample count to split the segments.
in all cases, prefixing each segment with + makes it relative to the previous segment. tiny detail, big difference ๐
๐ธ Examples
- split the input audio stream into three output audio streams โ starting at the start of the input audio stream and storing that in the 1st output audio stream, then following at the 60th second and storing that in the 2nd output audio stream, and last after the 150th second of the input audio stream stored in the 3rd output audio stream:
asegment=timestamps="60|150"
๐ select, aselect
select frames to pass in output. the main character filter fr fr ๐
this filter accepts the following options:
expr,eโ set the expression, which is evaluated for each input frame.
if the expression evaluates to zero, the frame is discarded ๐
if the evaluation result is negative or NaN, the frame is sent to the first output; otherwise it's sent to the output with index ceil(val)-1, assuming the input index starts from 0.
for example, a value of 1.2 corresponds to the output with index ceil(1.2)-1 = 2-1 = 1, that is the second output. math ate, honestly ๐
outputs,nโ set the number of outputs. which output the selected frame goes to is based on the result of the evaluation. default value is1.
the expression can contain the following constants:
nโ the (sequential) number of the filtered frame, starting from0.selected_nโ the (sequential) number of the selected frame, starting from0.prev_selected_nโ the sequential number of the last selected frame. it'sNANif undefined.TBโ the timebase of the input timestamps.ptsโ the PTS (Presentation TimeStamp) of the filtered frame, expressed inTBunits. it'sNANif undefined.tโ the PTS of the filtered frame, expressed in seconds. it'sNANif undefined.prev_ptsโ the PTS of the previously filtered frame. it'sNANif undefined.prev_selected_ptsโ the PTS of the last previously filtered frame. it'sNANif undefined.prev_selected_tโ the PTS of the last previously selected frame, expressed in seconds. it'sNANif undefined.start_ptsโ the first PTS in the stream which is notNAN. it remainsNANif not found.start_tโ the first PTS, in seconds, in the stream which is notNAN. it remainsNANif not found.pict_type(video only) โ the type of the filtered frame. it can assume one of these values:I,P,B,S,SI,SP,BI.interlace_type(video only) โ the frame interlace type. it can assume one of these values:PROGRESSIVEโ the frame is progressive (not interlaced).TOPFIRSTโ the frame is top-field-first.BOTTOMFIRSTโ the frame is bottom-field-first.
consumed_sample_n(audio only) โ the number of selected samples before the current frame.samples_n(audio only) โ the number of samples in the current frame.sample_rate(audio only) โ the input sample rate.keyโ this is1if the filtered frame is a key-frame,0otherwise. ๐posโ the position in the file of the filtered frame,-1if the information is not available (e.g. for synthetic video). deprecated, do not use ๐ซscene(video only) โ a value between0and1to indicate a new scene; a low value reflects a low probability for the current frame to introduce a new scene, while a higher value means the current frame is more likely to be one (see the example below). dramatic scene change detected ๐ญconcatdec_selectโ the concat demuxer can select only part of a concat input file by setting an inpoint and an outpoint, but the output packets may not be entirely contained in the selected interval. by using this variable, it's possible to skip frames generated by the concat demuxer which are not exactly contained in the selected interval.
this works by comparing the frame pts against the lavf.concat.start_time and the lavf.concat.duration packet metadata values which are also present in the decoded frames. iykyk ๐ง
concatdec_selectโ this one's-1when the frame pts is at leaststart_timeand either the duration metadata is missing or the frame pts is less thanstart_time + duration. Otherwise it's0, and it'sNaNif thestart_timemetadata is missing ๐ญ
So basically, bestie: an input frame gets selected if its pts lands inside the interval the concat demuxer set up. That's the whole vibe check.
iw(video only) โ the width of the input video frame ๐ih(video only) โ the height of the input video frame ๐view(video only) โ the view ID for multi-view video ๐
The default value of the select expression is "1".
๐ธ Examples ๐ธ
- Select all frames in input:
select
Which, like, is literally the same as:
select=1
- Skip all frames (ghosting everyone, iconic behaviour):
select=0
- Select only I-frames:
select='eq(pict_type\,I)'
- Select one frame every 100:
select='not(mod(n\,100))'
- Select only frames contained in the 10-20 time interval:
select=between(t\,10\,20)
- Select only I-frames contained in the 10-20 time interval:
select=between(t\,10\,20)*eq(pict_type\,I)
- Select frames with a minimum distance of 10 seconds:
select='isnan(prev_selected_t)+gte(t-prev_selected_t\,10)'
- Use
aselectto select only audio frames with samples number > 100:
aselect='gt(samples_n\,100)'
- Create a mosaic of the first scenes:
ffmpeg -i video.avi -vf select='gt(scene\,0.4)',scale=160:120,tile -frames:v 1 preview.png
Ngl, comparing scene against a value between 0.3 and 0.5 is generally a sane choice ๐ซถ
- Send even and odd frames to separate outputs, and compose them:
select=n=2:e='mod(n, 2)+1' [odd][even]; [odd] pad=h=2*ih [tmp]; [tmp][even] overlay=y=h
- Select useful frames from an ffconcat file which is using inpoints and outpoints but where the source files are not intra frame only:
ffmpeg -copyts -vsync 0 -segment_time_metadata 1 -i input.ffconcat -vf select=concatdec_select -af aselect=concatdec_select output.avi
๐ sendcmd, asendcmd ๐
Send commands to filters in the filtergraph. Like passing notes in class, but the notes are legal filter commands โจ
These filters read commands that then get sent to other filters in the filtergraph.
sendcmd must be inserted between two video filters, and asendcmd must be inserted between two audio filters โ but other than that, they act the exact same way. Twins fr fr ๐
The specification of commands can be provided in the filter arguments with the commands option, or in a file specified by the filename option.
These filters accept the following options:
commands,cโ set the commands to be read and sent to the other filters ๐จfilename,fโ set the filename of the commands to be read and sent to the other filters ๐
๐ฆ Commands syntax ๐ฆ
A commands description is a sequence of interval specifications, and each one holds a list of commands to run when a particular event related to that interval happens. The event is typically the current frame time entering or leaving a given time interval โฐ
An interval is specified by this syntax:
<START>[-<END>] <COMMANDS>;
The time interval is specified by the START and END times. END is optional and defaults to the maximum time.
A frame's current time counts as inside the interval if it's in [START, END), meaning the time is greater or equal to START and lesser than END โ half-open intervals, we love to see it ๐
COMMANDS is a sequence of one or more command specifications separated by ,, all relating to that interval. The syntax of a command specification is:
[<FLAGS>] <TARGET> <COMMAND> <ARG>
FLAGS is optional and says which type of events relating to the time interval actually enable sending the command. It has to be a non-null sequence of identifier flags separated by + or | and enclosed between [ and ].
The following flags are recognized:
enterโ the command is sent when the current frame timestamp enters the specified interval. In other words, it's sent when the previous frame timestamp was not in the given interval and the current one is ๐ชโจleaveโ the command is sent when the current frame timestamp leaves the specified interval. In other words, it's sent when the previous frame timestamp was in the given interval and the current one isn't ๐exprโ the command ARG is interpreted as an expression, and the result of that expression gets passed as ARG.
The expression is evaluated through the eval API and can contain the following constants:
POSโ original position in the file of the frame, or undefined if undefined for the current frame. Deprecated, do not use ๐PTSโ the presentation timestamp in input.Nโ the count of the input frame for video or audio, starting from0.Tโ the time in seconds of the current frame.TSโ the start time in seconds of the current command interval.TEโ the end time in seconds of the current command interval.TIโ the interpolated time of the current command interval,TI = (T - TS) / (TE - TS).Wโ the video frame width.Hโ the video frame height.
If FLAGS isn't specified, a default value of [enter] is assumed. No cap ๐งข
TARGET specifies the target of the command โ usually the name of the filter class or a specific filter instance name ๐ฏ
COMMAND specifies the name of the command for the target filter.
ARG is optional and specifies the optional list of argument for the given COMMAND.
Between one interval specification and another, whitespaces โ or sequences of characters starting with # until the end of line โ are ignored, and you can use them to annotate comments ๐
A simplified BNF description of the commands specification syntax follows:
<COMMAND_FLAG> ::= "enter" | "leave"
<COMMAND_FLAGS> ::= <COMMAND_FLAG> [(+|"|")<COMMAND_FLAG>]
<COMMAND> ::= ["[" <COMMAND_FLAGS> "]"] <TARGET> <COMMAND> [<ARG>]
<COMMANDS> ::= <COMMAND> [,<COMMANDS>]
<INTERVAL> ::= <START>[-<END>] <COMMANDS>
<INTERVALS> ::= <INTERVAL>[;<INTERVALS>]
๐ Examples ๐
- Specify audio tempo change at second 4:
asendcmd=c='4.0 atempo tempo 1.5',atempo
- Target a specific filter instance:
asendcmd=c='4.0 atempo@my tempo 1.5',atempo@my
- Specify a list of drawtext and hue commands in a file.
# show text in the interval 5-10
5.0-10.0 [enter] drawtext reinit 'fontfile=FreeSerif.ttf:text=hello world',
[leave] drawtext reinit 'fontfile=FreeSerif.ttf:text=';
# desaturate the image in the interval 15-20
15.0-20.0 [enter] hue s 0,
[enter] drawtext reinit 'fontfile=FreeSerif.ttf:text=nocolor',
[leave] hue s 1,
[leave] drawtext reinit 'fontfile=FreeSerif.ttf:text=color';
# apply an exponential saturation fade-out effect, starting from time 25
25 [enter] hue s exp(25-t)
A filtergraph that allows you to read and process the above command list stored in a file test.cmd can be specified with:
sendcmd=f=test.cmd,drawtext=fontfile=FreeSerif.ttf:text='',hue
โญ setpts, asetpts โญ
Change the PTS (presentation timestamp) of the input frames. Time is a social construct anyway โณ๐ซ
setpts works on video frames, asetpts works on audio frames.
This filter accepts the following options:
exprโ the expression which is evaluated for each frame to construct its timestamp.strip_fps(video only) โ boolean option that determines if the original framerate and frame duration metadata is unset. If you set it to true, be advised that a sane frame rate should be explicitly specified if output is sent to a constant frame rate muxer. Default isfalseโ ๏ธ
The expression is evaluated through the eval API and can contain the following constants:
FRAME_RATE,FRโ frame rate, only defined for constant frame-rate video.PTSโ the presentation timestamp in input.Nโ the count of the input frame for video, or the number of consumed samples not including the current frame for audio, starting from0.NB_CONSUMED_SAMPLESโ the number of consumed samples, not including the current frame (only audio).NB_SAMPLES,Sโ the number of samples in the current frame (only audio).SAMPLE_RATE,SRโ the audio sample rate.STARTPTSโ the PTS of the first frame.STARTTโ the time in seconds of the first frame.INTERLACEDโ state whether the current frame is interlaced.Tโ the time in seconds of the current frame.POSโ original position in the file of the frame, or undefined if undefined for the current frame; deprecated, do not use ๐PREV_INPTSโ the previous input PTS.PREV_INTโ previous input time in seconds.PREV_OUTPTSโ the previous output PTS.PREV_OUTTโ previous output time in seconds.RTCTIMEโ the wallclock (RTC) time in microseconds. This is deprecated, usetime(0)instead.RTCSTARTโ the wallclock (RTC) time at the start of the movie in microseconds.TBโ the timebase of the input timestamps.T_CHANGEโ time of the first frame after command was applied, or time of the first frame if no commands.
๐ Examples ๐
- Start counting PTS from zero:
setpts=PTS-STARTPTS
- Apply fast motion effect:
setpts=0.5*PTS
- Apply slow motion effect:
setpts=2.0*PTS
- Set fixed rate of 25 frames per second:
setpts=N/(25*TB)
- Apply a random jitter effect of +/-100 TB units:
setpts=PTS+randomi(0, -100\,100)
- Set fixed rate 25 fps with some jitter:
setpts='1/(25*TB) * (N + 0.05 * sin(N*2*PI/25))'
- Apply an offset of 10 seconds to the input PTS:
setpts=PTS+10/TB
- Generate timestamps from a "live source" and rebase onto the current timebase:
setpts='(RTCTIME - RTCSTART) / (TB * 1000000)'
- Generate timestamps by counting samples:
asetpts=N/SR/TB
๐ซ Commands ๐ซ
Both filters support all above options as commands. Slay, equal opportunity icon behaviour ๐
๐ง setrange ๐ง
Force color range for the output video frame.
The setrange filter marks the color range property for the output frames. It does not change the input frame โ it only sets the corresponding property, which affects how the frame is treated by the filters that come after it ๐โจ
The filter accepts the following options:
rangeโ bestie, this one picks the color range. Available values are:autoโ keep the same color range property.unspecified,unknownโ set the color range as unspecified.limited,tv,mpegโ set the color range as limited.full,pc,jpegโ set the color range as full.
๐๏ธ settb, asettb
This sets the timebase used for the output framesโ timestamps. Itโs mainly useful for testing timebase configuration. It accepts these parameters:
expr,tbโ the expression that gets evaluated into the output timebase.
The value for tb is an arithmetic expression representing a rational. That expression can contain the constants "AVTB" (the default timebase), "intb" (the input timebase), and "sr" (the sample rate, audio only). Default value is "intb".
Examples:
- Set the timebase to
1/25:
settb=expr=1/25
- Set the timebase to
1/10:
settb=expr=0.1
- Set the timebase to
1001/1000:
settb=1+0.001
- Set the timebase to
2*intb:
settb=2*intb
- Set the default timebase value:
settb=AVTB
๐ showcqt ๐
Okay so this one converts input audio into a video output that represents the frequency spectrum logarithmically, using the Brown-Puckette constant Q transform algorithm with direct frequency domain coefficient calculation. And yes, the transform itself is not really constant Q โ instead the Q factor is actually variable/clamped. It gives you a musical tone scale from E0 to D#10, which is honestly iconic. ๐
The filter accepts the following options:
size,sโ specify the video size for the output. It must be even. For the syntax of this option, check the"Video size"section in theffmpeg-utilsmanual. Default value is"1920x1080".fps,rate,rโ set the output frame rate. Default value is25.bar_hโ set the bargraph height. It must be even. Default value is-1, which computes the bargraph height automatically.axis_hโ set the axis height. It must be even. Default value is-1, which computes the axis height automatically.sono_hโ set the sonogram height. It must be even. Default value is-1, which computes the sonogram height automatically.fullhdโ set the fullhd resolution. This option is deprecated โ usesize,sinstead. Default value is1.sono_v,volumeโ specify the sonogram volume expression. It can contain these variables:bar_vโ thebar_vevaluated expression.frequency,freq,fโ the frequency where it is evaluated.timeclamp,tcโ the value of thetimeclampoption.
And these functions:
a_weighting(f)โ A-weighting of equal loudness.b_weighting(f)โ B-weighting of equal loudness.c_weighting(f)โ C-weighting of equal loudness.
Default value is 16.
bar_v,volume2โ specify the bargraph volume expression. It can contain these variables:sono_vโ thesono_vevaluated expression.frequency,freq,fโ the frequency where it is evaluated.timeclamp,tcโ the value of thetimeclampoption.
And these functions:
a_weighting(f)โ A-weighting of equal loudness.b_weighting(f)โ B-weighting of equal loudness.c_weighting(f)โ C-weighting of equal loudness.
Default value is "sono_v".
sono_g,gammaโ specify the sonogram gamma. Lower gamma makes the spectrum more contrast, higher gamma makes the spectrum have more range. Default value is3. Acceptable range is"[1, 7]".bar_g,gamma2โ specify the bargraph gamma. Default value is1. Acceptable range is"[1, 7]".bar_tโ specify the bargraph transparency level. Lower value makes the bargraph sharper. Default value is1. Acceptable range is"[0, 1]".timeclamp,tcโ specify the transform timeclamp. At low frequency, there is a trade-off between accuracy in the time domain and accuracy in the frequency domain. Iftimeclampis lower, events in the time domain are represented more accurately (such as a fast bass drum); otherwise, events in the frequency domain are represented more accurately (such as a bass guitar). Acceptable range is"[0.002, 1]". Default value is0.17.attackโ set attack time in seconds. The default is0(disabled). Otherwise, it limits future samples by applying asymmetric windowing in the time domain, useful when low latency is required. Accepted range is"[0, 1]".basefreqโ specify the transform base frequency. Default value is20.01523126408007475, which is a frequency 50 cents below E0. Acceptable range is"[10, 100000]".endfreqโ specify the transform end frequency. Default value is20495.59681441799654, which is a frequency 50 cents above D#10. Acceptable range is"[10, 100000]".coeffclampโ this option is deprecated and ignored.tlengthโ specify the transform length in the time domain. Use this option to control the accuracy trade-off between time domain and frequency domain at every frequency sample. It can contain these variables:frequency,freq,fโ the frequency where it is evaluated.timeclamp,tcโ the value of thetimeclampoption.
Default value is "384*tc/(384+tc*f)".
countโ specify the transform count for every video frame. Default value is6. Acceptable range is"[1, 30]".fcountโ specify the transform count for every single pixel. Default value is0, which makes it computed automatically. Acceptable range is"[0, 10]".fontfileโ specify a font file for use with freetype to draw the axis. If not specified, use the embedded font. Note that drawing with a font file or embedded font is not implemented with custombasefreqandendfreqโ use theaxisfileoption instead.fontโ specify a fontconfig pattern. This has lower priority thanfontfile. The":"in the pattern may be replaced by"|"to avoid unnecessary escaping.fontcolorโ specify a font color expression. This is an arithmetic expression that should return integer value0xRRGGBB. It can contain these variables:frequency,freq,fโ the frequency where it is evaluated.timeclamp,tcโ the value of thetimeclampoption.
And these functions:
midi(f)โ midi number of frequencyf. Some midi numbers: E0(16), C1(24), C2(36), A4(69).r(x),g(x),b(x)โ red, green, and blue value of intensityx.
Default value is "st(0, (midi(f)-59.5)/12); st(1, if(between(ld(0),0,1), 0.5-0.5*cos(2*PI*ld(0)), 0)); r(1-ld(1)) + b(ld(1))".
axisfileโ specify an image file to draw the axis. This option overrides thefontfileandfontcoloroptions.axis,textโ enable/disable drawing text to the axis. If it is set to0, drawing to the axis is disabled, ignoring thefontfileandaxisfileoptions. Default value is1.cspโ set colorspace. The accepted values are:unspecifiedโ unspecified (default).bt709โ BT.709.fccโ FCC.bt470bgโ BT.470BG or BT.601-6 625.smpte170mโ SMPTE-170M or BT.601-6 525.smpte240mโ SMPTE-240M.bt2020nclโ BT.2020 with non-constant luminance.
cschemeโ set the spectrogram color scheme. This is a list of floating point values with format"left_r|left_g|left_b|right_r|right_g|right_b". The default is"1|0.5|0|0|0.5|1".
Examples:
- Playing audio while showing the spectrum:
ffplay -f lavfi 'amovie=a.mp3, asplit [a][out1]; [a] showcqt [out0]'
- Same as above, but with frame rate 30 fps:
ffplay -f lavfi 'amovie=a.mp3, asplit [a][out1]; [a] showcqt=fps=30:count=5 [out0]'
- Playing at 1280x720:
ffplay -f lavfi 'amovie=a.mp3, asplit [a][out1]; [a] showcqt=s=1280x720:count=4 [out0]'
- Disable sonogram display:
sono_h=0
- A1 and its harmonics: A1, A2, (near)E3, A3:
ffplay -f lavfi 'aevalsrc=0.1*sin(2*PI*55*t)+0.1*sin(4*PI*55*t)+0.1*sin(6*PI*55*t)+0.1*sin(8*PI*55*t),
asplit[a][out1]; [a] showcqt [out0]'
- Same as above, but with more accuracy in the frequency domain:
ffplay -f lavfi 'aevalsrc=0.1*sin(2*PI*55*t)+0.1*sin(4*PI*55*t)+0.1*sin(6*PI*55*t)+0.1*sin(8*PI*55*t),
asplit[a][out1]; [a] showcqt=timeclamp=0.5 [out0]'
- Custom volume:
bar_v=10:sono_v=bar_v*a_weighting(f)
- Custom gamma, now the spectrum is linear to the amplitude:
bar_g=2:sono_g=2
- Custom
tlengthequation:
tc=0.33:tlength='st(0,0.17); 384*tc / (384 / ld(0) + tc*f /(1-ld(0))) + 384*tc / (tc*f / ld(0) + 384 /(1-ld(0)))'
- Custom
fontcolorandfontfile, C-note is colored green, others are colored blue:
fontcolor='if(mod(floor(midi(f)+0.5),12), 0x0000FF, g(1))':fontfile=myfont.ttf
- Custom font using fontconfig:
font='Courier New,Monospace,mono|bold'
- Custom frequency range with custom axis using an image file:
axisfile=myaxis.png:basefreq=40:endfreq=10000
๐ showcwt ๐
This one converts input audio into a video output representing the frequency spectrum using Continuous Wavelet Transform and Morlet wavelet. The filter accepts the following options:
size,sโ specify the video size for the output. For the syntax of this option, check the"Video size"section in theffmpeg-utilsmanual. Default value is"640x512".rate,rโ set the output frame rate. Default value is25.scaleโ set the frequency scale used. Allowed values are:linearlogbarkmelerbssqrtcbrtqdrtfm
Default value is "linear".
iscaleโ set the intensity scale used. Allowed values are:linearlogsqrtcbrtqdrt
Default value is "log".
minโ set the minimum frequency that will be used in output. Default is20 Hz.maxโ set the maximum frequency that will be used in output. Default is20000 Hz. The real frequency upper limit depends on the input audioโs sample rate, and such will be enforced on this value when it is set to a value greater than the Nyquist frequency.iminโ set the minimum intensity that will be used in output.imaxโ set the maximum intensity that will be used in output.logbโ sets the logarithmic basis for brightness strength when mapping calculated magnitude values onto pixel values. Allowed range is0to1, default is0.0001โจdeviationโ sets the frequency deviation. Lower values than1are more frequency oriented, higher values than1are more time oriented. Allowed range is0to10, default is1๐ppsโ sets the number of pixel output per each second in one row. Allowed range is1to1024, default is64๐modeโ sets the output visual mode. Allowed values are:magnitudeโ show magnitude ๐phaseโ show only phase ๐magphaseโ show combination of magnitude and phase. Magnitude is mapped to brightness and phase to color ๐channelโ show unique color per channel magnitude ๐จstereoโ show unique color per stereo difference ๐ฆ
Default value is "magnitude".
slideโ sets the output slide method. Allowed values are:replacescrollframe
directionโ sets the direction method for the output slide method. Allowed values are:lrโ direction from left to right โก๏ธrlโ direction from right to left โฌ ๏ธudโ direction from up to down โฌ๏ธduโ direction from down to up โฌ๏ธ
barโ sets the ratio of bargraph display to display size. Default is0๐rotationโ sets color rotation, must be in[-1.0, 1.0]range. Default value is0๐ซ
๐ธ showfreqs ๐ธ
Okay so this one converts input audio into a video output representing the audio power spectrum โ audio amplitude is on the Y-axis while frequency is on the X-axis ๐ literally the whole vibe in one picture.
The filter accepts the following options:
size,sโ specify size of video. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Default is"1024x512"๐ผ๏ธrate,rโ set video rate. Default is25โฑ๏ธmodeโ set display mode. This sets how each frequency bin will be represented. It accepts the following values:linebardot
Default is "bar".
ascaleโ set amplitude scale. It accepts the following values:linโ linear scale ๐sqrtโ square root scale ๐ฑcbrtโ cubic root scale ๐งlogโ logarithmic scale ๐ฒ
Default is "log".
fscaleโ set frequency scale. It accepts the following values:linโ linear scale ๐logโ logarithmic scale ๐ฒrlogโ reverse logarithmic scale ๐
Default is "lin".
win_sizeโ set window size. Allowed range is from16to65536. Default is2048๐ชwin_funcโ set windowing function. It accepts the following values:rect,bartlett,hanning,hamming,blackman,welch,flattop,bharris,bnuttall,bhann,sine,nuttall,lanczos,gauss,tukey,dolph,cauchy,parzen,poisson,bohman,kaiser. Default is"hanning"๐งoverlapโ set window overlap. In range[0, 1]. Default is1, which means optimal overlap for the selected window function will be picked ๐ซถaveragingโ set time averaging. Setting this to0will display current maximal peaks. Default is1, which means time averaging is disabled โณcolorsโ specify list of colors separated by space or by'|'which will be used to draw channel frequencies. Unrecognized or missing colors will be replaced by white color ๐คcmodeโ set channel display mode. It accepts the following values:combinedseparate
Default is "combined".
minampโ set minimum amplitude used in"log"amplitude scaler ๐dataโ set data display mode. It accepts the following values:magnitudephasedelay
Default is "magnitude".
channelsโ set channels to use when processing audio. By default all are processed ๐ง
๐ฆ showspatial ๐ฆ
This one converts stereo input audio into a video output, representing the spatial relationship between two channels โ the whole left-right lore, visualized ๐
The filter accepts the following options:
size,sโ specify the video size for the output. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Default value is"512x512"๐ผ๏ธwin_sizeโ set window size. Allowed range is from1024to65536. Default size is4096๐ชwin_funcโ set window function. It accepts the following values:rect,bartlett,hann,hanning,hamming,blackman,welch,flattop,bharris,bnuttall,bhann,sine,nuttall,lanczos,gauss,tukey,dolph,cauchy,parzen,poisson,bohman,kaiser. Default value is"hann"โจrate,rโ set output framerate โฑ๏ธ
๐ฅ showspectrum ๐ฅ
Converts input audio into a video output representing the audio frequency spectrum โ no cap, this is the one you've definitely seen in every music visualizer ever ๐
The filter accepts the following options:
size,sโ specify the video size for the output. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Default value is"640x512"๐slideโ specify how the spectrum should slide along the window. It accepts the following values:replaceโ the samples start again on the left when they reach the right ๐scrollโ the samples scroll from right to left โฌ ๏ธfullframeโ frames are only produced when the samples reach the right ๐๏ธrscrollโ the samples scroll from left to right โก๏ธlreplaceโ the samples start again on the right when they reach the left ๐
Default value is "replace".
modeโ specify display mode. It accepts the following values:combinedโ all channels are displayed in the same row ๐ฏseparateโ all channels are displayed in separate rows ๐
Default value is combined.
colorโ specify display color mode. It accepts the following values:channelโ each channel is displayed in a separate color ๐จintensityโ each channel is displayed using the same color scheme ๐กrainbowโ each channel is displayed using the rainbow color scheme ๐morelandโ each channel is displayed using the moreland color scheme ๐งnebulaeโ each channel is displayed using the nebulae color scheme โ๏ธfireโ each channel is displayed using the fire color scheme ๐ฅfieryโ each channel is displayed using the fiery color scheme ๐fruitโ each channel is displayed using the fruit color scheme ๐coolโ each channel is displayed using the cool color scheme ๐งmagmaโ each channel is displayed using the magma color scheme ๐greenโ each channel is displayed using the green color scheme ๐viridisโ each channel is displayed using the viridis color scheme ๐plasmaโ each channel is displayed using the plasma color scheme ๐cividisโ each channel is displayed using the cividis color scheme ๐terrainโ each channel is displayed using the terrain color scheme โฐ๏ธ
Default value is channel.
scaleโ specify scale used for calculating intensity color values. It accepts the following values:linโ linear ๐sqrtโ square root, default ๐ฑcbrtโ cubic root ๐งlogโ logarithmic ๐ฒ4thrtโ 4th root ๐5thrtโ 5th root ๐ฟ
Default value is sqrt.
fscaleโ specify frequency scale. It accepts the following values:linโ linear ๐logโ logarithmic ๐ฒ
Default value is lin.
saturationโ set saturation modifier for displayed colors. Negative values provide alternative color scheme.0is no saturation at all. Saturation must be in[-10.0, 10.0]range. Default value is1๐จwin_funcโ set window function. It accepts the following values:rect,bartlett,hann,hanning,hamming,blackman,welch,flattop,bharris,bnuttall,bhann,sine,nuttall,lanczos,gauss,tukey,dolph,cauchy,parzen,poisson,kaiser. Default value is"hann"๐ชorientationโ set orientation of time vs frequency axis. Can be"vertical"or"horizontal". Default is"vertical"๐overlapโ set ratio of overlap window. Default value is0. When value is1overlap is set to recommended size for the specific window function currently used ๐ซถgainโ set scale gain for calculating intensity color values. Default value is1๐dataโ set which data to display. Can be"magnitude", default, or"phase", or unwrapped phase:"uphase"๐rotationโ set color rotation, must be in[-1.0, 1.0]range. Default value is0๐ซstartโ set start frequency from which to display spectrogram. Default is0๐๏ธstopโ set stop frequency to which to display spectrogram. Default is0๐๏ธfpsโ set upper frame rate limit. Default is"auto", unlimited ๐legendโ draw time and frequency axes and legends. Default is disabled ๐drangeโ set dynamic range used to calculate intensity color values. Default is120dBFS. Allowed range is from10to200๐limitโ set upper limit of input audio samples volume in dBFS. Default is0dBFS. Allowed range is from-100to100๐opacityโ set opacity strength when using pixel format output with alpha component ๐ป
The usage is very similar to the showwaves filter; see the examples in that section ๐
โจ Examples โจ
- Large window with logarithmic color scaling:
showspectrum=s=1280x480:scale=log
- Complete example for a colored and sliding spectrum per channel using
ffplay:
ffplay -f lavfi 'amovie=input.mp3, asplit [a][out1];
[a] showspectrum=mode=separate:color=intensity:slide=1:scale=cbrt [out0]'
๐ showspectrumpic ๐
Converts input audio into a single video frame, representing the audio frequency spectrum โ one frame, one gorgeous spectrum, no motion ๐ผ๏ธโจ
The filter accepts the following options:
okay bestie we're still in the thick of it โ carrying straight on with the back half of the showspectrumpic options, no recap, no yapping, let's go โจ
size,sโ sets the video size for the output. For the syntax of this option, go check the "Video size" section in theffmpeg-utilsmanual. Default value is4096x2048. ๐modeโ picks the display mode, aka how the channels get laid out. It accepts the following values:combinedโ all channels are displayed in the same rowseparateโ all channels are displayed in separate rows
Default value is combined. ๐ซถ
colorโ sets the display color mode. It accepts the following values:channelโ each channel is displayed in a separate colorintensityโ each channel is displayed using the same color schemerainbowโ each channel is displayed using the rainbow color schememorelandโ each channel is displayed using the moreland color schemenebulaeโ each channel is displayed using the nebulae color schemefireโ each channel is displayed using the fire color schemefieryโ each channel is displayed using the fiery color schemefruitโ each channel is displayed using the fruit color schemecoolโ each channel is displayed using the cool color schememagmaโ each channel is displayed using the magma color schemegreenโ each channel is displayed using the green color schemeviridisโ each channel is displayed using the viridis color schemeplasmaโ each channel is displayed using the plasma color schemecividisโ each channel is displayed using the cividis color schemeterrainโ each channel is displayed using the terrain color scheme
Default value is intensity. ๐ (the color scheme roster is genuinely giving aesthetic mood board, ngl)
scaleโ the scale used for calculating intensity color values. It accepts the following values:linโ linearsqrtโ square root, defaultcbrtโ cubic rootlogโ logarithmic4thrtโ 4th root5thrtโ 5th root
Default value is log.
๐ okay so the page literally tagssqrtwith "default" up there and then says the default islogright after. I'm not fixing it, I'm just reporting it, bestie โ the manpage said what it said.
fscaleโ sets the frequency scale. It accepts the following values:linโ linearlogโ logarithmic
Default value is lin.
saturationโ sets the saturation modifier for displayed colors. Negative values give you an alternative color scheme, and0is no saturation at all. Saturation must be in the[-10.0, 10.0]range. Default value is1. ๐win_funcโ sets the window function. It accepts the following values:rectbartletthannhanninghammingblackmanwelchflattopbharrisbnuttallbhannsinenuttalllanczosgausstukeydolphcauchyparzenpoissonbohmankaiser
Default value is hann. ๐ฆ
orientationโ sets the orientation of the time vs frequency axis. Can beverticalorhorizontal. Default isvertical.gainโ sets the scale gain used for calculating intensity color values. Default value is1.legendโ draws the time and frequency axes plus legends. Default is enabled. ๐rotationโ sets color rotation, must be in the[-1.0, 1.0]range. Default value is0.startโ sets the start frequency from which to display the spectrogram. Default is0.stopโ sets the stop frequency to which to display the spectrogram. Default is0.drangeโ sets the dynamic range used to calculate intensity color values. Default is120 dBFS. Allowed range is from10to200.limitโ sets the upper limit of input audio samples volume in dBFS. Default is0 dBFS. Allowed range is from-100to100.opacityโ sets the opacity strength when you're using a pixel format output that has an alpha component. ๐ง
Examples ๐ธ
- Extract an audio spectrogram of a whole audio track into a
1024x1024picture usingffmpeg:
ffmpeg -i audio.flac -lavfi showspectrumpic=s=1024x1024 spectrogram.png
showvolume ๐
Turns input audio volume into a video output. The filter accepts the following options:
rate,rโ sets the video rate.bโ sets the border width, allowed range is[0, 5]. Default is1.wโ sets the channel width, allowed range is[80, 8192]. Default is400.hโ sets the channel height, allowed range is[1, 900]. Default is20.fโ sets the fade, allowed range is[0, 1]. Default is0.95.cโ sets the volume color expression. The expression can use the following variables:VOLUMEโ current max volume of channel in dB.PEAKโ current peak.CHANNELโ current channel number, starting from0.
tโ if set, displays channel names. Default is enabled.vโ if set, displays volume values. Default is enabled.oโ sets orientation, can be horizontal:hor vertical:v, default ish.sโ sets step size, allowed range is[0, 5]. Default is0, which means step is disabled.pโ sets background opacity, allowed range is[0, 1]. Default is0.mโ sets metering mode, can be peak:por rms:r, default isp.dsโ sets display scale, can be linear:linor log:log, default islin.dmโ in second. If set to >0., display a line for the max level in the previous seconds. Default is disabled:0.dmcโ the color of the max line. Use whendmoption is set to >0. Default is:orange. ๐
showwaves ๐
Converts input audio to a video output that represents the samples waves. The filter accepts the following options:
size,sโ sets the video size for the output. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Default value is600x240.modeโ sets the display mode. Available values are:pointโ draw a point for each sample.lineโ draw a vertical line for each sample.p2pโ draw a point for each sample and a line between them.clineโ draw a centered vertical line for each sample.
Default value is point.
nโ sets the number of samples which are printed on the same column. A larger value will decrease the frame rate. Must be a positive integer. This option can be set only if the value forrateis not explicitly specified. โ ๏ธrate,rโ sets the (approximate) output frame rate. This is done by setting the optionn. Default value is25.split_channelsโ sets whether channels should be drawn separately or overlap. Default value is0.colorsโ sets colors separated by'|'which are going to be used for drawing of each channel.scaleโ sets the amplitude scale. Available values are:linโ linear.logโ logarithmic.sqrtโ square root.cbrtโ cubic root.
Default is linear.
drawโ sets the draw mode. This is mostly useful to set for highn. Available values are:scaleโ scale pixel values for each drawn sample.fullโ draw every sample directly.
Default value is scale. ๐ฅ
Examples ๐
- Output the input file audio and the corresponding video representation at the same time:
amovie=a.mp3,asplit[out0],showwaves[out1]
- Create a synthetic signal and show it with
showwaves, forcing a frame rate of 30 frames per second:
aevalsrc=sin(1*2*PI*t)*sin(880*2*PI*t):cos(2*PI*200*t),asplit[out0],showwaves=r=30[out1]
showwavespic ๐
Converts input audio to a single video frame that represents the samples waves. One frame, iconic behavior. The filter accepts the following options:
size,sโ sets the video size for the output. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Default value is600x240.split_channelsโ sets whether channels should be drawn separately or overlap. Default value is0.colorsโ sets colors separated by'|'which are going to be used for drawing of each channel.scaleโ sets the amplitude scale. Available values are:linโ linear.logโ logarithmic.sqrtโ square root.cbrtโ cubic root.
Default is linear.
drawโ sets the draw mode. Available values are:scaleโ scale pixel values for each drawn sample.fullโ draw every sample directly.
Default value is scale.
filterโ sets the filter mode. Available values are:averageโ use average samples values for each drawn sample.peakโ use peak samples values for each drawn sample.
Default value is average. ๐
Examples โจ
- Extract a channel split representation of the wave form of a whole audio track in a
1024x800picture usingffmpeg:
ffmpeg -i audio.flac -lavfi showwavespic=split_channels=1:s=1024x800 waveform.png
sidedata, asidedata ๐ฆ
Deletes frame side data, or selects frames based on it. Very much the "block or keep" energy. This filter accepts the following options:
modeโ sets the mode of operation of the filter. Can be one of the following:selectโ select every frame with side data oftype.deleteโ delete side data oftype. Iftypeis not set, delete all side data in the frame.
typeโ sets the side data type used with all modes. Must be set forselectmode. โ ๏ธ Possible values are:PANSCANA53_CCSTEREO3DMATRIXENCODINGDOWNMIX_INFOREPLAYGAINDISPLAYMATRIXAFDMOTION_VECTORSSKIP_SAMPLESAUDIO_SERVICE_TYPEMASTERING_DISPLAY_METADATAGOP_TIMECODESPHERICALCONTENT_LIGHT_LEVELICC_PROFILES12M_TIMECODEDYNAMIC_HDR_PLUSREGIONS_OF_INTERESTVIDEO_ENC_PARAMSSEI_UNREGISTEREDFILM_GRAIN_PARAMSDETECTION_BOUNDING_BOXESDETECTION_BBOXESDOVI_RPU_BUFFERDOVI_METADATADYNAMIC_HDR_VIVIDAMBIENT_VIEWING_ENVIRONMENTVIDEO_HINT
(yes, all twenty-nine of them, I counted so you don't have to ๐ญ)
spectrumsynth ๐ฎ
Synthesizes audio from two input video spectrums โ first input stream represents magnitude across time, second represents phase across time. The filter will transform from frequency domain as displayed in videos back to time domain as presented in audio output. Literally reversing the whole art project back into sound, we love a glow-up in both directions ๐ซถ
still more to come, bestie โ don't close the tab ๐
Okay so this filter is mainly here to reverse processed showspectrum filter outputs, but bestie it can also synthesize sound from other spectrograms too. Lowkey in that case the results are gonna be poor if the phase data is not available, because then the phase data has to be recreated, usually just from random noise. For best results use gray-only output ("channel" color mode in showspectrum filter) and "log" scale for magnitude video and "lin" scale for phase video. To produce phase, for the 2nd video, use "data" option. Input videos should generally use "fullframe" slide mode because that saves resources needed for decoding video.
The filter accepts the following options:
sample_rateโ set the sample rate of the output audio; the sample rate of the audio that the spectrum was generated from may differ, no cap.channelsโ set the number of channels represented in the input video spectrums.scaleโ set the scale that was used when generating the magnitude input spectrum. Can be"lin"or"log". Default is"log".slideโ set the slide that was used when generating the inputs spectrums. Can be"replace","scroll","fullframe"or"rscroll". Default is"fullframe".win_funcโ set the window function used for resynthesis.overlapโ set the window overlap, in range"[0, 1]". Default is1, which means the optimal overlap for the selected window function will be picked.orientationโ set the orientation of input videos. Can be"vertical"or"horizontal". Default is"vertical".
Examples
- First create magnitude and phase videos from audio, assuming the audio is stereo with
44100sample rate, then resynthesize the videos back to audio withspectrumsynth:
ffmpeg -i input.flac -lavfi showspectrum=mode=separate:scale=log:overlap=0.875:color=channel:slide=fullframe:data=magnitude -an -c:v rawvideo magnitude.nut
ffmpeg -i input.flac -lavfi showspectrum=mode=separate:scale=lin:overlap=0.875:color=channel:slide=fullframe:data=phase -an -c:v rawvideo phase.nut
ffmpeg -i magnitude.nut -i phase.nut -lavfi spectrumsynth=channels=2:sample_rate=44100:win_func=hann:overlap=0.875:slide=fullframe output.flac
๐ธ split, asplit ๐ธ
Split the input into several identical outputs. Bestie, it's giving copy-paste energy but make it filtergraph.
"asplit" works with audio input, and "split" works with video.
The filter accepts a single parameter which specifies the number of outputs. If unspecified, it defaults to 2.
Examples
- Create two separate outputs from the same input:
[in] split [out0][out1]
- To create 3 or more outputs, you need to specify the number of outputs, like in:
[in] asplit=3 [out0][out1][out2]
- Create two separate outputs from the same input, one cropped and one padded:
[in] split [splitout1][splitout2];
[splitout1] crop=100:100:0:0 [cropout];
[splitout2] pad=200:200:100:100 [padout];
- Create 5 copies of the input audio with
ffmpeg:
ffmpeg -i INPUT -filter_complex asplit=5 OUTPUT
๐ zmq, azmq ๐
Receive commands sent through a libzmq client, and forward them to filters in the filtergraph. Literally the group-chat relay of the filter world.
"zmq" and "azmq" work as pass-through filters. "zmq" must be inserted between two video filters, and "azmq" between two audio filters. Both are capable of sending messages to any filter type.
To enable these filters you need to install the libzmq library and headers and configure FFmpeg with --enable-libzmq.
For more information about libzmq see: http://www.zeromq.org/
The "zmq" and "azmq" filters work as a libzmq server, which receives messages sent through a network interface defined by the bind_address (or the abbreviation "b") option. Default value of this option is tcp://localhost:5555. You may want to alter this value to your needs, but do not forget to escape any ':' signs (see filtergraph escaping).
The received message must be in the form:
<TARGET> <COMMAND> [<ARG>]
TARGET specifies the target of the command, usually the name of the filter class or a specific filter instance name. The default filter instance name uses the pattern Parsed_<filter_name>_<index>, but you can override this by using the filter_name@id syntax (see Filtergraph syntax).
COMMAND specifies the name of the command for the target filter.
ARG is optional and specifies the optional argument list for the given COMMAND.
Upon reception, the message is processed and the corresponding command is injected into the filtergraph. Depending on the result, the filter will send a reply to the client, adopting the format:
<ERROR_CODE> <ERROR_REASON>
<MESSAGE>
MESSAGE is optional.
Examples
Look at tools/zmqsend for an example of a zmq client which can be used to send commands processed by these filters.
Consider the following filtergraph generated by ffplay. In this example the last overlay filter has an instance name. All other filters will have default instance names.
ffplay -dumpgraph 1 -f lavfi "
color=s=100x100:c=red [l];
color=s=100x100:c=blue [r];
nullsrc=s=200x100, zmq [bg];
[bg][l] overlay [bg+l];
[bg+l][r] overlay@my=x=100 "
To change the color of the left side of the video, the following command can be used:
echo Parsed_color_0 c yellow | tools/zmqsend
To change the right side:
echo Parsed_color_1 c pink | tools/zmqsend
To change the position of the right side:
echo overlay@my x 150 | tools/zmqsend
๐ MULTIMEDIA SOURCES ๐
okay bestie so here's the rundown of all the multimedia sources we've got rn:
๐ amovie
literally the same energy as the movie source, except it picks an audio stream by default. that's the whole vibe. iykyk โจ
๐ฆ avsynctest
generates an Audio/Video Sync Test, no cap. the stream it makes periodically flashes a video frame and drops a beep in the audio โ super useful for checking out A/V sync issues. it's giving diagnostic icon ๐
it accepts these options:
size,sโ set the output video size. default is"hd720".framerate,frโ set the output video frame rate. default is30.samplerate,srโ set the output audio sample rate. default is44100.amplitude,aโ set the output audio beep amplitude. default is0.7.period,pโ set the output audio beep period in seconds. default is3.delay,dlโ set the output video flash delay in number of frames. default is0.cycle,cโ enable cycling of video delays; by default it's disabled.duration,dโ set stream output duration. by default duration is unlimited.fg,bg,agโ set foreground/background/additional color.
Commands
this source supports some of the above options as commands too ๐ซถ
๐ธ movie
reads audio and/or video stream(s) out of a movie container. main character behavior honestly.
it accepts these parameters:
filenameโ the name of the resource to read. and like, it's not necessarily a file โ it can also be a device or a stream accessed through some protocol.format_name,fโ specifies the format assumed for the movie to read, and it can be either the name of a container or an input device. if you don't specify it, the format is guessed from movie_name or by probing.seek_point,spโ specifies the seek point in seconds. frames will be output starting from this seek point. the parameter is evaluated withav_strtod, so the numerical value may be suffixed by an IS postfix. default value is"0".streams,sโ specifies the streams to read. you can give several streams, separated by+. the source will then have as many outputs, in the same order. syntax is explained in the "Stream specifiers" section in the ffmpeg manual. two special names,dvandda, specify respectively the default (best suited) video and audio stream. default isdv, ordaif the filter is called asamovie.stream_index,siโ specifies the index of the video stream to read. if the value is-1, the most suitable video stream gets auto-selected. default value is-1. deprecated btw. if the filter is calledamovie, it'll select audio instead of video.loopโ specifies how many times to read the stream in sequence. if the value is0, the stream will be looped infinitely. default value is1.
heads up bestie: when the movie is looped the source timestamps are not changed, so it'll generate non monotonically increasing timestamps. no cap, that's a real thing.
discontinuityโ specifies the time difference between frames above which the point is considered a timestamp discontinuity, which gets removed by adjusting the later timestamps.dec_threadsโ specifies the number of threads for decoding.format_optsโ specify format options for the opened file. format options can be given as a list of key=value pairs separated by:. the following example shows how to addprotocol_whitelistandprotocol_blacklistoptions:
ffplay -f lavfi
"movie=filename='1.sdp':format_opts='protocol_whitelist=file,rtp,udp\:protocol_blacklist=http'"
it lets you overlay a second video on top of the main input of a filtergraph, like this graph right here:
input -----------> deltapts0 --> overlay --> output
^
|
movie --> scale--> deltapts1 -------+
Examples
- skip
3.2seconds from the start of the AVI filein.avi, and overlay it on top of the input labelledin:
movie=in.avi:seek_point=3.2, scale=180:-1, setpts=PTS-STARTPTS [over];
[in] setpts=PTS-STARTPTS [main];
[main][over] overlay=16:16 [out]
- read from a video4linux2 device, and overlay it on top of the input labelled
in:
movie=/dev/video0:f=video4linux2, scale=180:-1, setpts=PTS-STARTPTS [over];
[in] setpts=PTS-STARTPTS [main];
[main][over] overlay=16:16 [out]
- read the first video stream and the audio stream with id
0x81fromdvd.vob; the video is connected to the pad namedvideoand the audio is connected to the pad namedaudio:
movie=dvd.vob:s=v:0+#0x81 [video] [audio]
Commands
both movie and amovie support these commands:
seekโ perform seek usingav_seek_frame. the syntax is:
seek stream_index|timestamp|flags
stream_index: if stream_index is-1, a default stream is selected, and timestamp is automatically converted from AV_TIME_BASE units to the stream specific time_base.timestamp: timestamp in AVStream.time_base units or, if no stream is specified, in AV_TIME_BASE units.flags: flags which select direction and seeking mode.
get_durationโ get movie duration in AV_TIME_BASE units.
๐ EXTERNAL LIBRARIES ๐
FFmpeg can be hooked up with a whole bunch of external libraries to add support for more formats. none of them are used by default bestie โ their use has to be explicitly requested by passing the appropriate flags to ./configure. that's the rule ๐
โญ Alliance for Open Media (AOM)
FFmpeg can make use of the AOM library for AV1 decoding and encoding. slay.
go to <http://aomedia.org/> and follow the instructions for installing the library. then pass --enable-libaom to configure to enable it.
๐ฅ AMD AMF/VCE
FFmpeg can use the AMD Advanced Media Framework library for accelerated H.264 and HEVC (only windows) encoding on hardware with Video Coding Engine (VCE). iconic.
to enable support you must obtain the AMF framework header files (version 1.4.9+) from <https://github.com/GPUOpen-LibrariesAndSDKs/AMF.git>.
create an AMF/ directory in the system include path. copy the contents of AMF/amf/public/include/ into that directory. then configure FFmpeg with --enable-amf.
initialization of the amf encoder happens in this order: 1) trying to initialize through dx11 (only windows) 2) trying to initialize through dx9 (only windows) 3) trying to initialize through vulkan.
to use the h.264 (AMD VCE) encoder on linux, amdgru-pro version 19.20+ and the amf-amdgpu-pro package are required (amdgru-pro contains it, but doesn't install it automatically). fr fr.
this driver can be installed using the amdgpu-pro-install script in the official amd driver archive.
๐ง AviSynth
FFmpeg can read AviSynth scripts as input. to enable support, pass --enable-avisynth to configure after installing the headers provided by <https://github.com/AviSynth/AviSynthPlus>. AviSynth+ can be configured to install only the headers by either passing -DHEADERS_ONLY:bool=on to the normal CMake-based build system, or by using the supplied GNUmakefile.
for Windows, the supported AviSynth variants are <http://avisynth.nl> for 32-bit builds and <http://avisynth.nl/index.php/AviSynth+> for 32-bit and 64-bit builds.
for Linux, macOS, and BSD, the only supported AviSynth variant is <https://github.com/AviSynth/AviSynthPlus>, starting with version 3.5.
okay so in 2016, AviSynth+ added support for building with GCC. however, due to the eccentricities of Windows' calling conventions, 32-bit GCC builds of AviSynth+ are not compatible with typical 32-bit builds of FFmpeg. ๐ญ by default, FFmpeg assumes compatibility with 32-bit MSVC builds of AviSynth+, since that's the most widely-used and entrenched build configuration. users can override this and enable support for 32-bit GCC builds of AviSynth+ by passing-DAVSC_WIN32_GCC32to--extra-cflagswhen configuring FFmpeg. 64-bit builds of FFmpeg are not affected, and can use either MSVC or GCC builds of AviSynth+ without any special flags. periodt. AviSynth(+) is loaded dynamically. distributors can build FFmpeg with--enable-avisynth, and the binaries will work regardless of the end user having AviSynth installed. if/when an end user would like to use AviSynth scripts, then they can install AviSynth(+) and FFmpeg will be able to find and use it to open scripts. ๐ซถ
๐ Chromaprint
FFmpeg can make use of the Chromaprint library for generating audio fingerprints. pass --enable-chromaprint to configure to enable it. see <https://acoustid.org/chromaprint>. lowkey obsessed with fingerprinting ngl.
๐ codec2
FFmpeg can make use of the codec2 library for codec2 decoding and encoding. there's currently no native decoder, so libcodec2 must be used for decoding.
go to <http://freedv.org/>, download Codec 2 source archive. build and install using CMake. Debian users can install the libcodec2-dev package instead. once libcodec2 is installed you can pass --enable-libcodec2 to configure to enable it.
the easiest way to use codec2 is with .c2 files, since they contain the mode information required for decoding. to encode such a file, use a .c2 file extension and give the libcodec2 encoder the -mode option:
ffmpeg -i input.wav -mode 700C output.c2
playback is as simple as:
ffplay output.c2
for a list of supported modes, run:
ffmpeg -h encoder=libcodec2
raw codec2 files are also supported. to make sense of them the mode in use needs to be specified as a format option:
ffmpeg -f codec2raw -mode 1300 -i input.raw output.wav
๐ dav1d
FFmpeg can make use of the dav1d library for AV1 video decoding. go to <https://code.videolan.org/videolan/dav1d> and follow the instructions for installing the library. then pass --enable-libdav1d to configure to enable it. โจ
๐ davs2
FFmpeg can make use of the davs2 library for AVS2-P2/IEEE1857.4 video decoding. go to <https://github.com/pkuvcl/davs2> and follow the instructions for installing the library. then pass --enable-libdavs2 to configure to enable it.
โ ๏ธ okay important: libdavs2 is under the GNU Public License Version 2 or later (see <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html> for details), so you must upgrade FFmpeg's license to GPL in order to use it.
๐ฆ uavs3d
FFmpeg can make use of the uavs3d library for AVS3-P2/IEEE1857.10 video decoding. go to <https://github.com/uavs3/uavs3d> and follow the instructions for installing the library. then pass --enable-libuavs3d to configure to enable it. ๐
Game Music Emu ๐ฎ๐ต
okay so bestie, FFmpeg can lowkey use the Game Music Emu library to read audio out of all those supported video game music file formats โ yes, the vibes of your fave retro soundtrack, decoded. To turn it on, pass --enable-libgme to configure. Go peep <https://bitbucket.org/mpyne/game-music-emu/overview>. โจ
Intel QuickSync Video ๐จ
FFmpeg can use Intel QuickSync Video (QSV) for accelerated decoding and encoding of multiple codecs. Iconic. But there's a catch, bestie: to use QSV, FFmpeg must be linked against the libmfx dispatcher, which is the thing that loads the actual decoding libraries.
The dispatcher is open source and can be downloaded from <https://github.com/lu-zero/mfx_dispatch.git>. FFmpeg needs to be configured with the --enable-libmfx option, and pkg-config needs to be able to locate the dispatcher's .pc files. No .pc files, no party. ๐ซถ
Kvazaar ๐ธ
FFmpeg can make use of the Kvazaar library for HEVC encoding.
Go to <https://github.com/ultravideo/kvazaar> and follow the instructions for installing the library. Then pass --enable-libkvazaar to configure to enable it. slay.
LAME ๐ง
FFmpeg can make use of the LAME library for MP3 encoding.
Go to <http://lame.sourceforge.net/> and follow the instructions for installing the library. Then pass --enable-libmp3lame to configure to enable it. that's the MP3 encoder of all time fr fr.
LCEVCdec ๐ง
FFmpeg can make use of the liblcevc_dec library for LCEVC enhancement layer decoding on supported bitstreams.
Go to <https://github.com/v-novaltd/LCEVCdec> and follow the instructions for installing the library. Then pass --enable-liblcevc-dec to configure to enable it.
๐ LCEVCdec is under the BSD-3-Clause-Clear License. noted, bestie โ keep that license clean.
libilbc ๐๏ธ
iLBC is a narrowband speech codec that has been made freely available by Google as part of the WebRTC project. libilbc is a packaging friendly copy of the iLBC codec. FFmpeg can make use of the libilbc library for iLBC decoding and encoding.
Go to <https://github.com/TimothyGu/libilbc> and follow the instructions for installing the library. Then pass --enable-libilbc to configure to enable it. ๐
libjxl ๐ผ๏ธ
JPEG XL is an image format intended to fully replace legacy JPEG for an extended period of life โ like, it's giving "the next main character image format." See <https://jpegxl.info/> for more information, and see <https://github.com/libjxl/libjxl> for the library source. You can pass --enable-libjxl to configure in order enable the libjxl wrapper. โจ
libvpx ๐ฌ
FFmpeg can make use of the libvpx library for VP8/VP9 decoding and encoding.
Go to <http://www.webmproject.org/> and follow the instructions for installing the library. Then pass --enable-libvpx to configure to enable it.
ModPlug ๐ผ
FFmpeg can make use of this library, originating in Modplug-XMMS, to read from MOD-like music files. See <https://github.com/Konstanty/libmodplug>. Pass --enable-libmodplug to configure to enable it. vintage tracker music nation rise ๐
OpenCORE, VisualOn, and Fraunhofer libraries ๐
Spun off Google Android sources, OpenCore, VisualOn and Fraunhofer libraries provide encoders for a number of audio codecs.
โ ๏ธ okay listen up because this part is important. OpenCORE and VisualOn libraries are under the Apache License 2.0 (see <http://www.apache.org/licenses/LICENSE-2.0> for details), which is incompatible to the LGPL version 2.1 and GPL version 2. You have to upgrade FFmpeg's license to LGPL version 3 (or if you have enabled GPL components, GPL version 3) by passing --enable-version3 to configure in order to use it.
โ ๏ธ and ALSO: the license of the Fraunhofer AAC library is incompatible with the GPL. Therefore, for GPL builds, you have to pass --enable-nonfree to configure in order to use it. To the best of our knowledge, it is compatible with the LGPL. no cap, read the fine print bestie.
OpenCORE AMR ๐
FFmpeg can make use of the OpenCORE libraries for AMR-NB decoding/encoding and AMR-WB decoding.
Go to <http://sourceforge.net/projects/opencore-amr/> and follow the instructions for installing the libraries. Then pass --enable-libopencore-amrnb and/or --enable-libopencore-amrwb to configure to enable them.
VisualOn AMR-WB encoder library ๐ค
FFmpeg can make use of the VisualOn AMR-WBenc library for AMR-WB encoding.
Go to <http://sourceforge.net/projects/opencore-amr/> and follow the instructions for installing the library. Then pass --enable-libvo-amrwbenc to configure to enable it.
Fraunhofer AAC library ๐
FFmpeg can make use of the Fraunhofer AAC library for AAC decoding & encoding.
Go to <http://sourceforge.net/projects/opencore-amr/> and follow the instructions for installing the library. Then pass --enable-libfdk-aac to configure to enable it.
Fraunhofer MPEG-H 3D Audio decoder library ๐
FFmpeg can make use of the Fraunhofer MPEG-H decoder library for MPEG-H 3DA decoding.
Go to <https://github.com/Fraunhofer-IIS/mpeghdec> and follow the instructions for installing the library. Then pass --enable-libmpeghdec --enable-nonfree to configure to enable it. (both flags, together, no skipping ๐
)
LC3 library ๐ถ
FFmpeg can make use of the Google LC3 library for LC3 decoding & encoding.
Go to <https://github.com/google/liblc3/> and follow the instructions for installing the library. Then pass --enable-liblc3 to configure to enable it.
OpenH264 ๐น
FFmpeg can make use of the OpenH264 library for H.264 decoding and encoding.
Go to <http://www.openh264.org/> and follow the instructions for installing the library. Then pass --enable-libopenh264 to configure to enable it.
For decoding, this library is much more limited than the built-in decoder in libavcodec โ like, currently, this library lacks support for decoding B-frames and some other main/high profile features. (It currently only supports constrained baseline profile and CABAC.) Using it is mostly useful for testing and for taking advantage of Cisco's patent portfolio license (<http://www.openh264.org/BINARY_LICENSE.txt>). so like, know what you're getting into, k? ๐ญ
OpenJPEG ๐
FFmpeg can use the OpenJPEG libraries for decoding/encoding J2K videos. Go to <http://www.openjpeg.org/> to get the libraries and follow the installation instructions. To enable using OpenJPEG in FFmpeg, pass --enable-libopenjpeg to ./configure.
rav1e ๐ฆ
FFmpeg can make use of rav1e (Rust AV1 Encoder) via its C bindings to encode videos. Go to <https://github.com/xiph/rav1e/> and follow the instructions to build the C library. To enable using rav1e in FFmpeg, pass --enable-librav1e to ./configure. rust girlies stay winning โจ
SVT-AV1 โก
FFmpeg can make use of the Scalable Video Technology for AV1 library for AV1 encoding.
Go to <https://gitlab.com/AOMediaCodec/SVT-AV1/> and follow the instructions for installing the library. Then pass --enable-libsvtav1 to configure to enable it.
SVT-JPEG-XS ๐๏ธ
FFmpeg can make use of the Scalable Video Technology for JPEG-XS library for JPEG-XS decoding and encoding.
Go to <https://github.com/OpenVisualCloud/SVT-JPEG-XS> and follow the instructions for installing the library. Then pass --enable-libsvtjpegxs to configure to enable it.
TwoLAME ๐ต
FFmpeg can make use of the TwoLAME library for MP2 encoding.
Go to <http://www.twolame.org/> and follow the instructions for installing the library. Then pass --enable-libtwolame to configure to enable it.
VapourSynth ๐ฆ
FFmpeg can read VapourSynth scripts as input. To enable support, pass --enable-vapoursynth to configure. Vapoursynth is detected via pkg-config. Versions 42 or greater supported. See <http://www.vapoursynth.com/>.
๐ Due to security concerns, Vapoursynth scripts will not be autodetected, so the input format has to be forced. Forff*CLI tools, add-f vapoursynthbefore the input-i yourscript.vpy. like:
-f vapoursynth -i yourscript.vpy
don't forget it or it simply won't work, bestie ๐
x264 ๐
FFmpeg can make use of the x264 library for H.264 encoding.
Go to <http://www.videolan.org/developers/x264.html> and follow the instructions for installing the library. Then pass --enable-libx264 to configure to enable it.
โ ๏ธ x264 is under the GNU Public License Version 2 or later (see <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html> for details), you must upgrade FFmpeg's license to GPL in order to use it.
x265 ๐
FFmpeg can make use of the x265 library for HEVC encoding.
Go to <http://x265.org/developers.html> and follow the instructions for installing the library. Then pass --enable-libx265 to configure to enable it.
โ ๏ธ x265 is under the GNU Public License Version 2 or later (see <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html> for details), you must upgrade FFmpeg's license to GPL in order to use it.
xavs ๐๏ธ
FFmpeg can make use of the xavs library for AVS encoding.
Go to <http://xavs.sf.net/> and follow the instructions for installing the library. Then pass --enable-libxavs to configure to enable it.
xavs2 ๐ฅ
FFmpeg can make use of the xavs2 library for AVS2-P2/IEEE1857.4 video encoding.
Go to <https://github.com/pkuvcl/xavs2> and follow the instructions for installing the library. Then pass --enable-libxavs2 to configure to enable it.
โ ๏ธ libxavs2 is under the GNU Public License Version 2 or later (see <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html> for details), you must upgrade FFmpeg's license to GPL in order to use it.
eXtra-fast Essential Video Encoder (XEVE) ๐
FFmpeg can make use of the XEVE library for EVC video encoding.
Go to <https://github.com/mpeg5/xeve> and follow the instructions for installing the XEVE library. Then pass --enable-libxeve to configure to enable it.
eXtra-fast Essential Video Decoder (XEVD) ๐ฌ
FFmpeg can make use of the XEVD library for EVC video decoding.
Go to <https://github.com/mpeg5/xevd> and follow the instructions for installing the XEVD library. Then pass --enable-libxevd to configure to enable it.
ZVBI ๐บ
ZVBI is a VBI decoding library which can be used by FFmpeg to decode DVB teletext pages and DVB teletext subtitles. (yes, the little text pages on old TV โ iconic behaviour.)
Go to <http://sourceforge.net/projects/zapping/> and follow the instructions for installing the library. Then pass --enable-libzvbi to configure to enable it.
๐ SUPPORTED FILE FORMATS ๐
You can use the -formats and -codecs options to have an exhaustive list. like, the FULL list, no tea left unspilled. ๐
File Formats ๐๏ธ
FFmpeg supports the following file formats through the libavformat library:
the columns go like this, mkay:
Name : Encoding @tab Decoding @tab Comments
3dostrโ decode:X4xmโ decode:Xโ 4X Technologies format, used in some games.8088flex TMVโ decode:XAAXโ decode:Xโ Audible Enhanced Audio format, used in audiobooks.AAโ decode:Xโ Audible Format 2, 3, and 4, used in audiobooks.ACT Voiceโ decode:Xโ contains G.729 audioAdobe Filmstripโ encode:Xยท decode:XAudio IFF (AIFF)โ encode:Xยท decode:XAmerican Laser Games MMโ decode:Xโ Multimedia format used in games like Mad Dog McCree.3GPP AMRโ demuxX, muxX๐Amazing Studio Packed Animation Fileโ muxXonly; multimedia format used in game Heart Of Darkness. ๐ฎApple HTTP Live Streamingโ muxXonly. ๐Artworx Data Formatโ muxXonly. ๐จInterplay ACMโ muxXonly; audio only format used in some Interplay games. ๐งADPโ muxXonly; audio format used on the Nintendo Gamecube. ๐ฎAFCโ muxXonly; audio format used on the Nintendo Gamecube. ๐ฎADS/SS2โ muxXonly; audio format used on the PS2. ๐ฎAPNGโ demuxX, muxXโจASFโ demuxX, muxX; Advanced / Active Streaming Format. ๐ฆASTโ demuxX, muxX; audio format used on the Nintendo Wii. ๐ฎAVIโ demuxX, muxX๐AviSynthโ muxXonly. ๐งAVRโ muxXonly; audio format used on Mac. ๐AVSโ muxXonly; multimedia format used by the Creature Shock game. ๐พBeam Software SIFFโ muxXonly; audio and video format used in some games by Beam Software. ๐ฎBethesda Softworks VIDโ muxXonly; used in some games from Bethesda Softworks. ๐ฎBinary textโ muxXonly. ๐คBinkโ muxXonly; multimedia format used by many games. ๐ฎBink Audioโ muxXonly; audio only multimedia format used by some games. ๐งBitmap Brothers JVโ muxXonly; used in Z and Z95 games. ๐น๏ธBRPโ muxXonly; Argonaut Games format. ๐ฎBrute Force & Ignoranceโ muxXonly; used in the game Flash Traffic: City of Angels. ๐BFSTMโ muxXonly; audio format used on the Nintendo WiiU (based on BRSTM). ๐ฎBRSTMโ muxXonly; audio format used on the Nintendo Wii. ๐ฎBW64โ muxXonly; Broadcast Wave 64bit. ๐BWFโ demuxX, muxX๐codec2 (raw)โ demuxX, muxX; must be given-modeformat option to decode correctly. โ ๏ธcodec2 (.c2 files)โ demuxX, muxX; contains header with version and mode info, simplifying playback. ๐งCRI ADXโ demuxX, muxX; audio-only format used in console video games. ๐ฎCRI AIXโ muxXonly. ๐ฎCRI HCAโ muxXonly; audio-only format used in console video games. ๐ฎDiscworld II BMVโ muxXonly. ๐ชInterplay C93โ muxXonly; used in the game Cyberia from Interplay. ๐ฎDelphine Software International CINโ muxXonly; multimedia format used by Delphine Software games. ๐ฎDigital Speech Standard (DSS)โ muxXonly. ๐๏ธCD+Gโ muxXonly; video format used by CD+G karaoke disks. ๐คPhantom Cineโ muxXonly. ๐ฅCommodore CDXLโ muxXonly; Amiga CD video format. ๐ฟCore Audio Formatโ demuxX, muxX; Apple Core Audio Format. ๐CRC testing formatโ demuxXonly. ๐งชCreative Voiceโ demuxX, muxX; created for the Sound Blaster Pro. ๐CRYO APCโ muxXonly; audio format used in some games by CRYO Interactive Entertainment. ๐ฎD-Cinema audioโ demuxX, muxX๐ฌDeluxe Paint Animationโ muxXonly. ๐จDCSTRโ muxXonly. ๐ฎDFAโ muxXonly; this format is used in Chronomaster game. โณDirectDraw Surfaceโ muxXonly. ๐ผ๏ธDSD Stream File (DSF)โ muxXonly. ๐งDV videoโ demuxX, muxX๐นDXAโ muxXonly; this format is used in the non-Windows version of the Feeble Files game and different game cutscenes repacked for use with ScummVM. ๐ฎElectronic Arts cdataโ muxXonly. ๐ฎElectronic Arts Multimediaโ muxXonly; used in various EA games; files have extensions like WVE and UV2. ๐ฎEnsoniq Paris Audio Fileโ muxXonly. ๐นFFM (FFserver live feed)โ demuxX, muxX๐กFlash (SWF)โ demuxX, muxXโกFlash 9 (AVM2)โ demuxX, muxX; only embedded audio is decoded. ๐FLI/FLC/FLX animationโ muxXonly;.fli/.flcfiles. ๐๏ธFlash Video (FLV)โ demuxX, muxX; Macromedia Flash video files. ๐ผframecrc testing formatโ demuxXonly. ๐งชFunCom ISSโ muxXonly; audio format used in various games from FunCom like The Longest Journey. ๐ฎG.723.1โ demuxX, muxXโ๏ธG.726โ muxXonly; Both left- and right-justified. โ๏ธG.729 BITโ demuxX, muxXโ๏ธG.729 rawโ muxXonly. โ๏ธGENHโ muxXonly; audio format for various games. ๐ฎGIF Animationโ demuxX, muxX๐GXFโ demuxX, muxX; General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers. ๐บHNMโ muxXonly; only version 4 supported, used in some games from Cryo Interactive. ๐ฎiCEDraw Fileโ muxXonly. ๐งICOโ demuxX, muxX; Microsoft Windows ICO. ๐ชid Quake II CIN videoโ muxXonly. ๐ฎid RoQโ demuxX, muxX; used in Quake III, Jedi Knight 2 and other computer games. ๐น๏ธIEC61937 encapsulationโ demuxX, muxX๐IFFโ muxXonly; Interchange File Format. ๐ฆIFVโ muxXonly; a format used by some old CCTV DVRs. ๐นiLBCโ demuxX, muxX๐งInterplay MVEโ muxXonly; format used in various Interplay computer games. ๐ฎIterated Systems ClearVideoโ muxXonly; I-frames only. ๐ผ๏ธIV8โ muxXonly; a format generated by IndigoVision 8000 video server. ๐นIVF (On2)โ demuxX, muxX; a format used by libvpx. ๐ฅInternet Video Recordingโ muxXonly. ๐IRCAMโ demuxX, muxX๐งLAFโ muxXonly; Limitless Audio Format. ๐งLATMโ demuxX, muxX๐งLMLM4โ muxXonly; used by Linux Media Labs MPEG-4 PCI boards. ๐งLOASโ muxXonly; contains LATM multiplexed AAC audio. ๐LRCโ demuxX, muxX๐LVFโ muxXonly. ๐ฎLXFโ muxXonly; VR native stream format, used by Leitch/Harris' video servers. ๐บMagic Lantern Video (MLV)โ muxXonly. ๐ทMatroskaโ demuxX, muxX๐Matroska audioโ demuxXonly. ๐งFFmpeg metadataโ demuxX, muxX; metadata in text format. ๐ท๏ธMAXIS XAโ muxXonly; used in Sim City 3000; file extension .xa. ๐๏ธMCAโ muxXonly; used in some games from Capcom; file extension .mca. ๐ฎMD Studioโ muxXonly. ๐ฎMetal Gear Solid: The Twin Snakesโ muxXonly. ๐Megalux Frameโ muxXonly; used by Megalux Ultimate Paint. ๐จMobiClip MODSโ muxXonly. ๐ฑMobiClip MOFLEXโ muxXonly. ๐ฑMobotix .mxgโ muxXonly. ๐นMonkey's Audioโ muxXonly. ๐Motion Pixels MVIโ muxXonly. ๐๏ธMOV/QuickTime/MP4โ demuxX, muxX; 3GP, 3GP2, PSP, iPod variants supported. ๐MP2โ demuxX, muxX๐งMP3โ demuxX, muxX๐งMPEG-1 Systemโ demuxX, muxX; muxed audio and video, VCD format supported. ๐MPEG-PS (program stream)โ demuxX, muxX; also known asVOBfile, SVCD and DVD format supported. ๐MPEG-TS (transport stream)โ demuxX, muxX; also known as DVB Transport Stream. ๐กMPEG-4โ demuxX, muxX; MPEG-4 is a variant of QuickTime. ๐ฌMSFโ muxXonly; audio format used on the PS3. ๐ฎMirillis FIC videoโ muxXonly; no cursor rendering. ๐ฑ๏ธMIDI Sample Dump Standardโ muxXonly. ๐นMIME multipart JPEGโ demuxXonly. ๐ผ๏ธMSN TCP webcamโ muxXonly; used by MSN Messenger webcam streams. ๐นMTVโ muxXonly. ๐บMusepackโ muxXonly. ๐งMusepack SV8โ muxXonly. ๐งMaterial eXchange Format (MXF)โ demuxX, muxX; SMPTE 377M, used by D-Cinema, broadcast industry. ๐ฌMaterial eXchange Format (MXF), D-10 Mappingโ demuxX, muxX; SMPTE 386M, D-10/IMX Mapping. ๐ฌNC camera feedโ muxXonly; NC (AVIP NC4600) camera streams. ๐นNIST SPeech HEader REsourcesโ muxXonly. ๐ฃ๏ธComputerized Speech Lab NSPโ muxXonly. ๐ฃ๏ธNTT TwinVQ (VQF)โ muxXonly; Nippon Telegraph and Telephone Corporation TwinVQ. โ๏ธNullsoft Streaming Videoโ muxXonly. ๐บNuppelVideoโ muxXonly. ๐๏ธNUTโ demuxX, muxX; NUT Open Container Format. ๐ฅOggโ demuxX, muxX๐งPlaystation Portable PMPโ muxXonly. ๐ฎPortable Voice Formatโ muxXonly. ๐๏ธRK Audio (RKA)โ muxXonly. ๐งTechnoTrend PVAโ muxXonly; used by TechnoTrend DVB PCI boards. ๐บQCPโ decode only, bestie (encode column is blank, decode isX) ๐raw ADTS (AAC)โ both ways, encodeX+ decodeXโจraw AC-3โ both ways, encodeX+ decodeX๐ฅraw AMR-NBโ decode only, encode blank / decodeX๐raw AMR-WBโ decode only, encode blank / decodeX๐raw APACโ decode only, encode blank / decodeX๐ฆraw APVโ both ways, encodeX+ decodeXโจraw aptXโ both ways, encodeX+ decodeX๐งraw aptX HDโ both ways, encodeX+ decodeX๐งraw Bonkโ decode only, encode blank / decodeX๐raw Chinese AVS videoโ both ways, encodeX+ decodeX๐ธraw DFPWMโ both ways, encodeX+ decodeXโจraw Diracโ both ways, encodeX+ decodeX๐raw DNxHDโ both ways, encodeX+ decodeX๐ฌraw DTSโ both ways, encodeX+ decodeX๐ฅraw DTS-HDโ decode only, encode blank / decodeX๐งraw E-AC-3โ both ways, encodeX+ decodeX๐ฅraw EVCโ both ways, encodeX+ decodeXโจraw FLACโ both ways, encodeX+ decodeX๐ถraw G.728โ decode only, encode blank / decodeX๐raw GSMโ decode only, encode blank / decodeX๐raw H.261โ both ways, encodeX+ decodeX๐ฅraw H.263โ both ways, encodeX+ decodeX๐ฅraw H.264โ both ways, encodeX+ decodeX๐raw HEVCโ both ways, encodeX+ decodeX๐raw Ingenient MJPEGโ decode only, encode blank / decodeX๐ผ๏ธraw MJPEGโ both ways, encodeX+ decodeX๐ผ๏ธraw MLPโ decode only, encode blank / decodeX๐งraw MPEGโ decode only, encode blank / decodeX๐ผraw MPEG-1โ decode only, encode blank / decodeX๐ผraw MPEG-2โ decode only, encode blank / decodeX๐ผraw MPEG-4โ both ways, encodeX+ decodeX๐ผraw NULLโ encode only, encodeX/ decode column blank ๐raw videoโ both ways, encodeX+ decodeX๐๏ธraw id RoQโ encode only, encodeX/ decode column blank ๐ฎraw OBUโ both ways, encodeX+ decodeXโจraw OSQโ decode only, encode blank / decodeX๐ตraw SBCโ both ways, encodeX+ decodeX๐งraw Shortenโ decode only, encode blank / decodeX๐ฉณraw TAKโ decode only, encode blank / decodeX๐ถraw TrueHDโ both ways, encodeX+ decodeX๐raw VC-1โ both ways, encodeX+ decodeX๐ฌraw PCM A-lawโ both ways, encodeX+ decodeX๐raw PCM mu-lawโ both ways, encodeX+ decodeX๐raw PCM Archimedes VIDCโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 8 bitโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 16 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 16 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 24 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 24 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 32 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 32 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 64 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM signed 64 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 8 bitโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 16 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 16 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 24 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 24 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 32 bit big-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM unsigned 32 bit little-endianโ both ways, encodeX+ decodeX๐๏ธraw PCM 16.8 floating point little-endianโ decode only, encode blank / decodeX๐raw PCM 24.0 floating point little-endianโ decode only, encode blank / decodeX๐raw PCM floating-point 32 bit big-endianโ both ways, encodeX+ decodeX๐raw PCM floating-point 32 bit little-endianโ both ways, encodeX+ decodeX๐raw PCM floating-point 64 bit big-endianโ both ways, encodeX+ decodeX๐raw PCM floating-point 64 bit little-endianโ both ways, encodeX+ decodeX๐RDTโ decode only, encode blank / decodeX๐กREDCODE R3Dโ decode only, encode blank / decodeX๐ฅ โ ๐ฌ File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.RealMediaโ both ways, encodeX+ decodeX๐บRedirectorโ decode only, encode blank / decodeX๐RedSparkโ decode only, encode blank / decodeXโกRenderware TeXture Dictionaryโ decode only, encode blank / decodeX๐งฑResolume DXVโ both ways, encodeX+ decodeX๐๏ธ โ ๐ฌ Encoding is only supported for the DXT1 (Normal Quality, No Alpha) texture format.RF64โ decode only, encode blank / decodeX๐ฆRL2โ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Audio and video format used in some games by Entertainment Software Partners.RPL/ARMovieโ decode only, encode blank / decodeX๐๏ธLego Mindstorms RSOโ both ways, encodeX+ decodeX๐คRSDโ decode only, encode blank / decodeX๐ตRTMPโ both ways, encodeX+ decodeX๐ก โ ๐ฌ Output is performed by publishing stream to RTMP serverRTPโ both ways, encodeX+ decodeX๐กRTSPโ both ways, encodeX+ decodeX๐ฅSample Dump eXchangeโ decode only, encode blank / decodeX๐๏ธSAPโ both ways, encodeX+ decodeX๐กSBGโ decode only, encode blank / decodeX๐ฎSDNSโ decode only, encode blank / decodeX๐SDPโ decode only, encode blank / decodeX๐SERโ decode only, encode blank / decodeX๐ญDigital Pictures SGAโ decode only, encode blank / decodeX๐ผ๏ธSega FILM/CPKโ both ways, encodeX+ decodeX๐ฎ โ ๐ฌ Used in many Sega Saturn console games.Silicon Graphics Movieโ decode only, encode blank / decodeX๐ฌSierra SOLโ decode only, encode blank / decodeX๐น๏ธ โ ๐ฌ .sol files used in Sierra Online games.Sierra VMDโ decode only, encode blank / decodeX๐ฟ โ ๐ฌ Used in Sierra CD-ROM games.Smackerโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Multimedia format used by many games.SMJPEGโ both ways, encodeX+ decodeX๐๏ธ โ ๐ฌ Used in certain Loki game ports.SMPTE 337M encapsulationโ decode only, encode blank / decodeX๐ปSmushโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Multimedia format used in some LucasArts games.Sony OpenMG (OMA)โ both ways, encodeX+ decodeX๐ง โ ๐ฌ Audio format used in Sony Sonic Stage and Sony Vegas.Sony PlayStation STRโ decode only, encode blank / decodeX๐ฎSony Wave64 (W64)โ both ways, encodeX+ decodeX๐SoX native formatโ both ways, encodeX+ decodeX๐๏ธSUN AU formatโ both ways, encodeX+ decodeXโ๏ธSUP raw PGS subtitlesโ both ways, encodeX+ decodeX๐ฌSVAGโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Audio format used in Konami PS2 games.TDSCโ decode only, encode blank / decodeX๐ทText filesโ decode only, encode blank / decodeX๐THPโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Used on the Nintendo GameCube.Tiertex Limited SEQโ decode only, encode blank / decodeX๐พ โ ๐ฌ Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.True Audioโ both ways, encodeX+ decodeX๐ถVAGโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Audio format used in many Sony PS2 games.VC-1 test bitstreamโ both ways, encodeX+ decodeX๐งชVidvox Hapโ both ways, encodeX+ decodeX๐ฌVivoโ decode only, encode blank / decodeX๐VPKโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Audio format used in Sony PS games.Marble WADYโ decode only, encode blank / decodeX๐ฒWAVโ both ways, encodeX+ decodeX๐Waveform Archiverโ decode only, encode blank / decodeX๐ผWavPackโ both ways, encodeX+ decodeX๐ถWebMโ both ways, encodeX+ decodeX๐Windows Televison (WTV)โ both ways, encodeX+ decodeX๐บWing Commander III movieโ decode only, encode blank / decodeX๐ โ ๐ฌ Multimedia format used in Origin's Wing Commander III computer game.Westwood Studios audioโ both ways, encodeX+ decodeX๐ง โ ๐ฌ Multimedia format used in Westwood Studios games.Westwood Studios VQAโ both ways, encodeX+ decodeX๐ฌ โ ๐ฌ Multimedia format used in Westwood Studios games.Wideband Single-bit Data (WSD)โ decode only, encode blank / decodeX๐ปWVEโ decode only, encode blank / decodeX๐ตKonami XMDโ decode only, encode blank / decodeX๐ฎXMVโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Microsoft video container used in Xbox games.XVAGโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Audio format used on the PS3.xWMAโ decode only, encode blank / decodeX๐ง โ ๐ฌ Microsoft audio container used by XAudio 2.eXtended BINary text (XBIN)โ both ways, encodeX+ decodeX๐YUV4MPEG pipeโ both ways, encodeX+ decodeX๐๏ธPsygnosis YOPโ decode only, encode blank / decodeX๐ฎ
Okay so the whole vibe of those two little columns: X means that the feature in that column โ encoding / decoding โ is supported. That's it, that's the whole legend ๐ซถ
๐ผ๏ธ Image Formats ๐ผ๏ธ
FFmpeg can read and write images for each frame of a video sequence, which is honestly iconic of it ๐ The following image formats are supported:
.Y.U.Vโ both ways, encodeX+ decodeX๐ โ ๐ฌ one raw file per componentAlias PIXโ both ways, encodeX+ decodeX๐จ โ ๐ฌ Alias/Wavefront PIX image formatanimated GIFโ both ways, encodeX+ decodeX๐APNGโ both ways, encodeX+ decodeXโจ โ ๐ฌ Animated Portable Network GraphicsBMPโ both ways, encodeX+ decodeX๐ผ๏ธ โ ๐ฌ Microsoft BMP imageBRender PIXโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Argonaut BRender 3D engine image format.CRIโ decode only, encode blank / decodeX๐ฅ โ ๐ฌ Cintel RAWDPXโ both ways, encodeX+ decodeX๐๏ธ โ ๐ฌ Digital Picture ExchangeEXRโ decode only, encode blank / decodeX๐ โ ๐ฌ OpenEXRFITSโ both ways, encodeX+ decodeX๐ญ โ ๐ฌ Flexible Image Transport SystemHDRโ both ways, encodeX+ decodeXโ๏ธ โ ๐ฌ Radiance HDR RGBE Image formatIMGโ decode only, encode blank / decodeX๐พ โ ๐ฌ GEM Raster imageJPEGโ both ways, encodeX+ decodeX๐ท โ ๐ฌ Progressive JPEG is not supported.JPEG 2000โ both ways, encodeX+ decodeX๐ผ๏ธJPEG-LSโ both ways, encodeX+ decodeX๐ผ๏ธJPEG-XSโE+E, so both ways via the external-library route ๐ธ โ ๐ฌ Supported through external library libsvtjpegxsLJPEGโ encode only, encodeX/ decode column blank ๐ โ ๐ฌ Lossless JPEGMedia 100โ decode only, encode blank / decodeX๐ฌMSPโ decode only, encode blank / decodeX๐จ โ ๐ฌ Microsoft Paint imagePAMโ both ways, encodeX+ decodeX๐๏ธ โ ๐ฌ PAM is a PNM extension with alpha support.PBMโ both ways, encodeX+ decodeXโซ โ ๐ฌ Portable BitMap imagePCDโ decode only, encode blank / decodeX๐ฟ โ ๐ฌ PhotoCDPCXโ both ways, encodeX+ decodeX๐๏ธ โ ๐ฌ PC PaintbrushPFMโ both ways, encodeX+ decodeX๐ โ ๐ฌ Portable FloatMap imagePGMโ both ways, encodeX+ decodeXโฌ โ ๐ฌ Portable GrayMap imagePGMYUVโ both ways, encodeX+ decodeX๐๏ธ โ ๐ฌ PGM with U and V components in YUV 4:2:0PGXโ decode only, encode blank / decodeX๐ โ ๐ฌ PGX file decoderPHMโ both ways, encodeX+ decodeX๐ โ ๐ฌ Portable HalfFloatMap imagePICโ decode only, encode blank / decodeX๐จ โ ๐ฌ Pictor/PC PaintPNGโ both ways, encodeX+ decodeX๐ฆ โ ๐ฌ Portable Network Graphics imagePPMโ both ways, encodeX+ decodeX๐จ โ ๐ฌ Portable PixelMap imagePSDโ decode only, encode blank / decodeX๐๏ธ โ ๐ฌ PhotoshopPTXโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ V.Flash PTX formatQOIโ both ways, encodeX+ decodeX๐ โ ๐ฌ Quite OK Image formatSGIโ both ways, encodeX+ decodeX๐ โ ๐ฌ SGI RGB image formatSun Rasterfileโ both ways, encodeX+ decodeXโ๏ธ โ ๐ฌ Sun RAS image formatTIFFโ both ways, encodeX+ decodeX๐ท โ ๐ฌ YUV, JPEG and some extension is not supported yet.Truevision Targaโ both ways, encodeX+ decodeX๐จ โ ๐ฌ Targa (.TGA) image formatVBNโ both ways, encodeX+ decodeX๐บ โ ๐ฌ Vizrt Binary Image formatWBMPโ both ways, encodeX+ decodeX๐ฑ โ ๐ฌ Wireless Application Protocol Bitmap image formatWebPโ encodeE/ decodeX๐ฆ โ ๐ฌ WebP image format, encoding supported through external library libwebpXBMโ both ways, encodeX+ decodeX๐ผ๏ธ โ ๐ฌ X BitMap image formatXFaceโ both ways, encodeX+ decodeX๐ โ ๐ฌ X-Face image formatXPMโ decode only, encode blank / decodeX๐จ โ ๐ฌ X PixMap image formatXWDโ both ways, encodeX+ decodeX๐ช โ ๐ฌ X Window Dump image format
Same legend as before, bestie: X means that the feature in that column โ encoding / decoding โ is supported. ๐
And E means that support is provided through an external library. So if you see an E, that's a "go install the library first" moment, not a "ffmpeg lied to me" moment ๐ซถ
๐ฌ Video Codecs ๐ฌ
Name : Encoding @tab Decoding @tab Comments โ same deal, here come the codecs:
4X Movieโ decode only, encode blank / decodeX๐ฎ โ ๐ฌ Used in certain computer games.8088flex TMVโ enc: โ ยท dec: XA64 multicolorโ enc: X ยท dec: โ โ creates video suitable to be played on a commodore 64 (multicolor mode) ๐น๏ธAmazing Studio PAF Videoโ enc: โ ยท dec: XAmerican Laser Games MMโ enc: โ ยท dec: X โ used in games like Mad Dog McCreeAmuse Graphics Movieโ enc: โ ยท dec: XAMV Videoโ enc: X ยท dec: X โ used in Chinese MP3 players โจANSI/ASCII artโ enc: โ ยท dec: XApple Intermediate Codecโ enc: โ ยท dec: XApple MJPEG-Bโ enc: โ ยท dec: XApple Pixletโ enc: โ ยท dec: XApple ProResโ enc: X ยท dec: X โ fourcc:apch,apcn,apcs,apco,ap4h,ap4xApple QuickDrawโ enc: โ ยท dec: X โ fourcc:qdrwAPVโ enc: โ ยท dec: XArgonaut Videoโ enc: โ ยท dec: X โ used in some Argonaut gamesAsus v1โ enc: X ยท dec: X โ fourcc:ASV1Asus v2โ enc: X ยท dec: X โ fourcc:ASV2ATI VCR1โ enc: โ ยท dec: X โ fourcc:VCR1ATI VCR2โ enc: โ ยท dec: X โ fourcc:VCR2Auravision Auraโ enc: โ ยท dec: XAuravision Aura 2โ enc: โ ยท dec: XAutodesk Animator Flic videoโ enc: โ ยท dec: XAutodesk RLEโ enc: โ ยท dec: X โ fourcc:AASCAV1โ enc: E ยท dec: E โ supported through external librarieslibaom,libdav1d,librav1eandlibsvtav1๐ฅAvid 1:1 10-bit RGB Packerโ enc: X ยท dec: X โ fourcc:AVrpAVS (Audio Video Standard) videoโ enc: โ ยท dec: X โ video encoding used by the Creature Shock gameAVS2-P2/IEEE1857.4โ enc: E ยท dec: E โ supported through external librarieslibxavs2andlibdavs2AVS3-P2/IEEE1857.10โ enc: โ ยท dec: E โ supported through external librarylibuavs3dAYUVโ enc: X ยท dec: X โ Microsoft uncompressed packed 4:4:4:4Beam Software VBโ enc: โ ยท dec: XBethesda VID videoโ enc: โ ยท dec: X โ used in some games from Bethesda SoftworksBink Videoโ enc: โ ยท dec: XBitJazz SheerVideoโ enc: โ ยท dec: XBitmap Brothers JV videoโ enc: โ ยท dec: Xy41p Brooktree uncompressed 4:1:1 12-bitโ enc: X ยท dec: XBrooktree ProSumer Videoโ enc: โ ยท dec: X โ fourcc:BT20Brute Force & Ignoranceโ enc: โ ยท dec: X โ used in the game Flash Traffic: City of AngelsC93 videoโ enc: โ ยท dec: X โ codec used in Cyberia gameCamStudioโ enc: โ ยท dec: X โ fourcc:CSCDCD+Gโ enc: โ ยท dec: X โ video codec for CD+G karaoke disks ๐คCDXLโ enc: โ ยท dec: X โ Amiga CD video codecChinese AVS videoโ enc: E ยท dec: X โ AVS1-P2, JiZhun profile, encoding through external librarylibxavsDelphine Software International CIN videoโ enc: โ ยท dec: X โ codec used in Delphine Software International gamesDiscworld II BMV Videoโ enc: โ ยท dec: XCineForm HDโ enc: X ยท dec: XCanopus HQโ enc: โ ยท dec: XCanopus HQAโ enc: โ ยท dec: XCanopus HQXโ enc: โ ยท dec: XCanopus Lossless Codecโ enc: โ ยท dec: XCDToonsโ enc: โ ยท dec: X โ codec used in various Broderbund gamesCinepakโ enc: โ ยท dec: XCirrus Logic AccuPakโ enc: X ยท dec: X โ fourcc:CLJRCPiA Video Formatโ enc: โ ยท dec: XCreative YUV (CYUV)โ enc: โ ยท dec: XDFAโ enc: โ ยท dec: X โ codec used in Chronomaster gameDiracโ enc: E ยท dec: X โ supported through the nativevc2(Dirac Pro) encoderDeluxe Paint Animationโ enc: โ ยท dec: XDNxHDโ enc: X ยท dec: X โ aka SMPTE VC3Duck TrueMotion 1.0โ enc: โ ยท dec: X โ fourcc:DUCKDuck TrueMotion 2.0โ enc: โ ยท dec: X โ fourcc:TM20Duck TrueMotion 2.0 RTโ enc: โ ยท dec: X โ fourcc:TR20DV (Digital Video)โ enc: X ยท dec: XDxtory capture formatโ enc: โ ยท dec: XFeeble Files/ScummVM DXAโ enc: โ ยท dec: X โ codec originally used in Feeble Files gameElectronic Arts CMV videoโ enc: โ ยท dec: X โ used in NHL 95 gameElectronic Arts Madcow videoโ enc: โ ยท dec: XElectronic Arts TGV videoโ enc: โ ยท dec: XElectronic Arts TGQ videoโ enc: โ ยท dec: XElectronic Arts TQI videoโ enc: โ ยท dec: XEscape 124โ enc: โ ยท dec: XEscape 130โ enc: โ ยท dec: XEVC / MPEG-5 Part 1โ enc: E ยท dec: E โ encoding and decoding supported through external librarieslibxeveandlibxevdFFmpeg video codec #1โ enc: X ยท dec: X โ lossless codec (fourcc:FFV1)Flash Screen Video v1โ enc: X ยท dec: X โ fourcc:FSV1Flash Screen Video v2โ enc: X ยท dec: XFlash Video (FLV)โ enc: X ยท dec: X โ Sorenson H.263 used in FlashFM Screen Capture Codecโ enc: โ ยท dec: XForward Uncompressedโ enc: โ ยท dec: XFrapsโ enc: โ ยท dec: XGo2Meetingโ enc: โ ยท dec: X โ fourcc:G2M2,G2M3Go2Webinarโ enc: โ ยท dec: X โ fourcc:G2M4Gremlin Digital Videoโ enc: โ ยท dec: XH.261โ enc: X ยท dec: XH.263 / H.263-1996โ enc: X ยท dec: XH.263+ / H.263-1998 / H.263 version 2โ enc: X ยท dec: XH.264 / AVC / MPEG-4 AVC / MPEG-4 part 10โ enc: E ยท dec: X โ encoding supported through external librarylibx264andOpenH264๐HEVCโ enc: X ยท dec: X โ encoding supported through external librarylibx265andlibkvazaarHNM version 4โ enc: โ ยท dec: XHuffYUVโ enc: X ยท dec: XHuffYUV FFmpeg variantโ enc: X ยท dec: XIBM Ultimotionโ enc: โ ยท dec: X โ fourcc:ULTIid Cinematic videoโ enc: โ ยท dec: X โ used in Quake IIid RoQ videoโ enc: X ยท dec: X โ used in Quake III, Jedi Knight 2, other computer games ๐ฎIFF ILBMโ enc: โ ยท dec: X โ IFF interleaved bitmapIFF ByteRun1โ enc: โ ยท dec: X โ IFF run length encoded bitmapInfinity IMM4โ enc: โ ยท dec: XIntel H.263โ enc: โ ยท dec: XIntel Indeo 2โ enc: โ ยท dec: XIntel Indeo 3โ enc: โ ยท dec: XIntel Indeo 4โ enc: โ ยท dec: XIntel Indeo 5โ enc: โ ยท dec: XInterplay C93โ enc: โ ยท dec: X โ used in the game Cyberia from InterplayInterplay MVE videoโ enc: โ ยท dec: X โ used in Interplay.MVEfilesJ2Kโ enc: X ยท dec: XKarl Morton's video codecโ enc: โ ยท dec: X โ codec used in Worms games ๐ชฑKega Game Video (KGV1)โ enc: โ ยท dec: X โ Kega emulator screen capture codecLagarithโ enc: โ ยท dec: XLCEVC / MPEG-5 LCEVC / MPEG-5 Part 2โ enc: โ ยท dec: E โ decoding supported through external libraryliblcevc-decLCL (LossLess Codec Library) MSZHโ enc: โ ยท dec: XLCL (LossLess Codec Library) ZLIBโ enc: E ยท dec: ELEAD MCMPโ enc: โ ยท dec: XLOCOโ enc: โ ยท dec: XLucasArts SANM/Smushโ enc: โ ยท dec: X โ used in LucasArts games / SMUSH animationslossless MJPEGโ enc: X ยท dec: XMagicYUV Videoโ enc: X ยท dec: XMandsoft Screen Capture Codecโ enc: โ ยท dec: XMicrosoft ATC Screenโ enc: โ ยท dec: X โ also known as Microsoft Screen 3Microsoft Expression Encoder Screenโ enc: โ ยท dec: X โ also known as Microsoft Titanium Screen 2Microsoft RLEโ enc: X ยท dec: XMicrosoft Screen 1โ enc: โ ยท dec: X โ also known as Windows Media Video V7 ScreenMicrosoft Screen 2โ enc: โ ยท dec: X โ also known as Windows Media Video V9 ScreenMicrosoft Video 1โ enc: โ ยท dec: XMimicโ enc: โ ยท dec: X โ used in MSN Messenger Webcam streams ๐ปMiro VideoXLโ enc: โ ยท dec: X โ fourcc:VIXLMJPEG (Motion JPEG)โ enc: X ยท dec: XMobotix MxPEG videoโ enc: โ ยท dec: XMotion Pixels videoโ enc: โ ยท dec: XMPEG-1 videoโ enc: X ยท dec: XMPEG-2 videoโ enc: X ยท dec: XMPEG-4 part 2โ enc: X ยท dec: X โlibxvidcorecan be used alternatively for encodingMPEG-4 part 2 Microsoft variant version 1โ enc: โ ยท dec: XMPEG-4 part 2 Microsoft variant version 2โ enc: X ยท dec: XMPEG-4 part 2 Microsoft variant version 3โ enc: X ยท dec: XNewtek SpeedHQโ enc: X ยท dec: XNintendo Gamecube THP videoโ enc: โ ยท dec: XNotchLCโ enc: โ ยท dec: XNuppelVideo/RTjpegโ enc: โ ยท dec: X โ video encoding used in NuppelVideo filesOn2 VP3โ enc: โ ยท dec: X โ still experimental โ ๏ธOn2 VP4โ enc: โ ยท dec: X โ fourcc:VP40On2 VP5โ enc: โ ยท dec: X โ fourcc:VP50On2 VP6โ enc: โ ยท dec: X โ fourcc:VP60,VP61,VP62On2 VP7โ enc: โ ยท dec: X โ fourcc:VP70,VP71VP8โ enc: E ยท dec: X โ fourcc:VP80, encoding supported through external librarylibvpxVP9โ enc: E ยท dec: X โ encoding supported through external librarylibvpxPinnacle TARGA CineWave YUV16โ enc: โ ยท dec: X โ fourcc:Y216Q-team QPEGโ enc: โ ยท dec: X โ fourccs:QPEG,Q1.0,Q1.1QuickTime 8BPS videoโ enc: โ ยท dec: XQuickTime Animation (RLE) videoโ enc: X ยท dec: X โ fourcc:'rle 'QuickTime Graphics (SMC)โ enc: X ยท dec: X โ fourcc:'smc 'QuickTime video (RPZA)โ enc: X ยท dec: X โ fourcc:rpzaR10K AJA Kona 10-bit RGB Codecโ enc: X ยท dec: XR210 Quicktime Uncompressed RGB 10-bitโ enc: X ยท dec: XRaw Videoโ enc: X ยท dec: XRealVideo 1.0โ enc: X ยท dec: XRealVideo 2.0โ enc: X ยท dec: XRealVideo 3.0โ enc: โ ยท dec: X โ still far from ideal ๐ฌRealVideo 4.0โ enc: โ ยท dec: XRealVideo 6.0โ enc: โ ยท dec: XRenderware TXD (TeXture Dictionary)โ enc: โ ยท dec: X โ texture dictionaries used by the Renderware EngineRivaTuner Videoโ enc: โ ยท dec: X โ fourcc:'RTV1'RL2 videoโ enc: โ ยท dec: X โ used in some games by Entertainment Software Partners- ScreenPressor โ dec:
X - Screenpresso โ dec:
X - Screen Recorder Gold Codec โ dec:
X - Sierra VMD video โ dec:
X- the video codec living inside Sierra VMD files ๐
- Silicon Graphics Motion Video Compressor 1 (MVC1) โ dec:
X - Silicon Graphics Motion Video Compressor 2 (MVC2) โ dec:
X - Silicon Graphics RLE 8-bit video โ dec:
X - Smacker video โ dec:
X- video encoding used in Smacker โจ
- SMPTE VC-1 โ dec:
X - Snow โ enc:
Xยท dec:X- experimental wavelet codec (
fourcc: SNOW) ๐ง
- experimental wavelet codec (
- Sony PlayStation MDEC (Motion DECoder) โ dec:
X - Sorenson Vector Quantizer 1 โ enc:
Xยท dec:Xfourcc: SVQ1
- Sorenson Vector Quantizer 3 โ dec:
Xfourcc: SVQ3
- Sunplus JPEG (SP5X) โ dec:
Xfourcc: SP5X
- TechSmith Screen Capture Codec โ dec:
Xfourcc: TSCC
- TechSmith Screen Capture Codec 2 โ dec:
Xfourcc: TSC2
- Theora โ enc:
Eยท dec:X- encoding supported through external library
libtheora
- encoding supported through external library
- Tiertex Limited SEQ video โ dec:
X- codec used in the DOS CD-ROM FlashBack game ๐ธ
- Ut Video โ enc:
Xยท dec:X - v210 QuickTime uncompressed 4:2:2 10-bit โ enc:
Xยท dec:X - v308 QuickTime uncompressed 4:4:4 โ enc:
Xยท dec:X - v408 QuickTime uncompressed 4:4:4:4 โ enc:
Xยท dec:X - v410 QuickTime uncompressed 4:4:4 10-bit โ enc:
Xยท dec:X - VBLE Lossless Codec โ dec:
X - vMix Video โ dec:
Xfourcc: 'VMX1'
- VMware Screen Codec / VMware Video โ dec:
X- the codec used in videos captured by VMware ๐
- Westwood Studios VQA (Vector Quantized Animation) video โ dec:
X - Windows Media Image โ dec:
X - Windows Media Video 7 โ enc:
Xยท dec:X - Windows Media Video 8 โ enc:
Xยท dec:X - Windows Media Video 9 โ dec:
X- not completely working โ bestie, that's literally a warning label ๐
- Wing Commander III / Xan โ dec:
X- used in Wing Commander III
.MVEfiles
- used in Wing Commander III
- Wing Commander IV / Xan โ dec:
X- used in Wing Commander IV
- Winnov WNV1 โ dec:
X - WMV7 โ enc:
Xยท dec:X - YAMAHA SMAF โ enc:
Xยท dec:X - Psygnosis YOP Video โ dec:
X - yuv4 โ enc:
Xยท dec:Xlibquicktimeuncompressed packed 4:2:0
- ZeroCodec Lossless Video โ dec:
X - ZLIB โ enc:
Xยท dec:X- part of LCL, encoder is experimental ๐
- Zip Motion Blocks Video โ enc:
Xยท dec:X- encoder works only in PAL8 โญ
Okay so the legend, because this table has lore:
Xmeans that the feature in that column (encoding / decoding) is supported ๐Emeans that support is provided through an external library
๐ Audio Codecs ๐
The columns are: Name ยท Encoding ยท Decoding ยท Comments ๐ฆ (same deal as before, X = supported, E = external library).
- 8SVX exponential โ dec:
X - 8SVX fibonacci โ dec:
X - AAC โ enc:
EXยท dec:X- encoding supported through internal encoder and external library
libfdk-aac๐ฅ
- encoding supported through internal encoder and external library
- AAC+ โ enc:
Eยท dec:IX- encoding supported through external library
libfdk-aac
- encoding supported through external library
- AC-3 โ enc:
IXยท dec:IX - ACELP.KELVIN โ dec:
X - ADPCM 4X Movie โ dec:
X - ADPCM Yamaha AICA โ dec:
X - ADPCM AmuseGraphics Movie โ dec:
X - ADPCM Argonaut Games โ enc:
Xยท dec:X - ADPCM CDROM XA โ dec:
X - ADPCM Creative Technology โ dec:
X16 -> 4,8 -> 4,8 -> 3,8 -> 2
- ADPCM Electronic Arts โ dec:
X- used in various EA titles ๐ฎ
- ADPCM Electronic Arts Maxis CDROM XS โ dec:
X- used in Sim City 3000
- ADPCM Electronic Arts R1 โ dec:
X - ADPCM Electronic Arts R2 โ dec:
X - ADPCM Electronic Arts R3 โ dec:
X - ADPCM Electronic Arts XAS โ dec:
X - ADPCM G.722 โ enc:
Xยท dec:X - ADPCM G.726 โ enc:
Xยท dec:X - ADPCM IMA Acorn Replay โ dec:
X - ADPCM IMA AMV โ enc:
Xยท dec:X- used in AMV files
- ADPCM IMA Cunning Developments โ dec:
X - ADPCM IMA Electronic Arts EACS โ dec:
X - ADPCM IMA Electronic Arts SEAD โ dec:
X - ADPCM IMA Funcom โ dec:
X - ADPCM IMA High Voltage Software ALP โ enc:
Xยท dec:X - ADPCM IMA Mobiclip MOFLEX โ dec:
X - ADPCM IMA QuickTime โ enc:
Xยท dec:X - ADPCM IMA Simon & Schuster Interactive โ enc:
Xยท dec:X - ADPCM IMA Ubisoft APM โ enc:
Xยท dec:X - ADPCM IMA Loki SDL MJPEG โ dec:
X - ADPCM IMA WAV โ enc:
Xยท dec:X - ADPCM IMA Westwood โ dec:
X - ADPCM ISS IMA โ dec:
X- used in FunCom games
- ADPCM IMA Dialogic โ dec:
X - ADPCM IMA Duck DK3 โ dec:
X- used in some Sega Saturn console games ๐น๏ธ
- ADPCM IMA Duck DK4 โ dec:
X- used in some Sega Saturn console games
- ADPCM IMA Radical โ dec:
X - ADPCM IMA Xbox โ dec:
X - ADPCM Microsoft โ enc:
Xยท dec:X - ADPCM MS IMA โ enc:
Xยท dec:X - ADPCM Nintendo Gamecube AFC โ dec:
X - ADPCM Nintendo Gamecube DTK โ dec:
X - ADPCM Nintendo THP โ dec:
X - ADPCM Playstation โ dec:
X - ADPCM QT IMA โ enc:
Xยท dec:X - ADPCM Sanyo โ dec:
X - ADPCM SEGA CRI ADX โ enc:
Xยท dec:X- used in Sega Dreamcast games
- ADPCM Shockwave Flash โ enc:
Xยท dec:X - ADPCM Sound Blaster Pro 2-bit โ dec:
X - ADPCM Sound Blaster Pro 2.6-bit โ dec:
X - ADPCM Sound Blaster Pro 4-bit โ dec:
X - ADPCM VIMA โ dec:
X- used in LucasArts SMUSH animations
- ADPCM Konami XMD โ dec:
X - ADPCM Westwood Studios IMA โ enc:
Xยท dec:X- used in Westwood Studios games like Command and Conquer ๐
- ADPCM Yamaha โ enc:
Xยท dec:X - ADPCM Zork โ dec:
X - AMR-NB โ enc:
Eยท dec:X- encoding supported through external library
libopencore-amrnb
- encoding supported through external library
- AMR-WB โ enc:
Eยท dec:X- encoding supported through external library
libvo-amrwbenc
- encoding supported through external library
- Amazing Studio PAF Audio โ dec:
X - Apple lossless audio โ enc:
Xยท dec:X- QuickTime
fourcc 'alac'๐
- QuickTime
- aptX โ enc:
Xยท dec:X- used in Bluetooth A2DP
- aptX HD โ enc:
Xยท dec:X- used in Bluetooth A2DP
- ATRAC1 โ dec:
X - ATRAC3 โ dec:
X - ATRAC3+ โ dec:
X - ATRAC9 โ dec:
X - Bink Audio โ dec:
X- used in Bink and Smacker files in many games
- Bonk audio โ dec:
X - CELT โ dec:
E- decoding supported through external library
libcelt
- decoding supported through external library
- codec2 โ enc:
Eยท dec:E- en/decoding supported through external library
libcodec2
- en/decoding supported through external library
- CRI HCA โ dec:
X - Delphine Software International CIN audio โ dec:
X- codec used in Delphine Software International games
- DFPWM โ enc:
Xยท dec:X - Digital Speech Standard - Standard Play mode (DSS SP) โ dec:
X - Discworld II BMV Audio โ dec:
X - COOK โ dec:
X- all versions except 5.1 are supported ๐
- DCA (DTS Coherent Acoustics) โ enc:
Xยท dec:X- supported extensions:
XCh,XXCH,X96,XBR,XLL,LBR(partially)
- supported extensions:
- Dolby E โ dec:
X - DPCM Cuberoot-Delta-Exact โ dec:
X- used in a few games
- DPCM Gremlin โ dec:
X - DPCM id RoQ โ enc:
Xยท dec:X- used in Quake III, Jedi Knight 2 and other computer games ๐ฅ
- DPCM Marble WADY โ dec:
X - DPCM Interplay โ dec:
X- used in various Interplay computer games
- DPCM Squareroot-Delta-Exact โ dec:
X- used in various games
- DPCM Sierra Online โ dec:
X- used in Sierra Online game audio files
- DPCM Sol โ dec:
X - DPCM Xan โ dec:
X- used in Origin's Wing Commander IV AVI files
- DPCM Xilam DERF โ dec:
X - DSD (Direct Stream Digital), least significant bit first โ dec:
X - DSD (Direct Stream Digital), most significant bit first โ dec:
X - DSD (Direct Stream Digital), least significant bit first, planar โ dec:
X - DSD (Direct Stream Digital), most significant bit first, planar โ dec:
X - DSP Group TrueSpeech โ dec:
X - DST (Direct Stream Transfer) โ dec:
X - DV audio โ dec:
X - Enhanced AC-3 โ enc:
Xยท dec:X - EVRC (Enhanced Variable Rate Codec) โ dec:
X - FLAC (Free Lossless Audio Codec) โ enc:
Xยท dec:IX๐ฆ - FTR Voice โ dec:
X - G.723.1 โ enc:
Xยท dec:X - G.728 โ dec:
X - G.729 โ dec:
X - GSM โ enc:
Eยท dec:X- encoding supported through external library
libgsm
- encoding supported through external library
- GSM Microsoft variant โ enc:
Eยท dec:X- encoding supported through external library
libgsm
- encoding supported through external library
- IAC (Indeo Audio Coder) โ dec:
X - iLBC (Internet Low Bitrate Codec) โ enc:
Eยท dec:EX- encoding and decoding supported through external library
libilbc
- encoding and decoding supported through external library
- IMC (Intel Music Coder) โ dec:
X - Interplay ACM โ dec:
X - LC3 โ enc:
Eยท dec:E- supported through external library
liblc3
- supported through external library
- MACE (Macintosh Audio Compression/Expansion) 6:1 โ dec:
X - Marian's A-pac audio โ dec:
X - MI-SC4 (Micronas SC-4 Audio) โ dec:
X - MLP (Meridian Lossless Packing) โ enc:
Xยท dec:X- used in DVD-Audio discs ๐ฟ
- Monkey's Audio โ dec:
X - MP1 (MPEG audio layer 1) โ dec:
IX - MP2 (MPEG audio layer 2) โ enc:
IXยท dec:IX- encoding is also supported through external library TwoLAME
- MP3 (MPEG audio layer 3) โ enc:
Eยท dec:IX- encoding supported through external library LAME; ADU MP3 and MP3onMP4 are also supported ๐ง
- MPEG-4 Audio Lossless Coding (ALS) โ dec:
X - MPEG-H 3D Audio โ dec:
E- decoding supported through external library
libmpeghdec
- decoding supported through external library
โฆand we're sliding straight back into the audio codec roll-call, no intro needed ๐
. Reading order for each line: encoding then decoding, and X means it's a yes.
- MobiClip FastAudio โ decode
Xonly. Encoder said no ๐ซ - Musepack SV7 โ decode
Xonly - Musepack SV8 โ decode
Xonly - Nellymoser Asao โ encode
X, decodeX. Both ways, slay โจ - On2 AVC (Audio for Video Codec) โ decode
Xonly - Opus โ encode
E, decodeX. Note on the page: encoding supported through external library libopus ๐ซถ - OSQ (Original Sound Quality) โ decode
Xonly - PCM A-law โ encode
X, decodeX - PCM mu-law โ encode
X, decodeX - PCM Archimedes VIDC โ encode
X, decodeX - PCM signed 8-bit planar โ encode
X, decodeX - PCM signed 16-bit big-endian planar โ encode
X, decodeX - PCM signed 16-bit little-endian planar โ encode
X, decodeX - PCM signed 24-bit little-endian planar โ encode
X, decodeX - PCM signed 32-bit little-endian planar โ encode
X, decodeX - PCM 32-bit floating point big-endian โ encode
X, decodeX - PCM 32-bit floating point little-endian โ encode
X, decodeX - PCM 64-bit floating point big-endian โ encode
X, decodeX - PCM 64-bit floating point little-endian โ encode
X, decodeX - PCM D-Cinema audio signed 24-bit โ encode
X, decodeX - PCM signed 8-bit โ encode
X, decodeX - PCM signed 16-bit big-endian โ encode
X, decodeX - PCM signed 16-bit little-endian โ encode
X, decodeX - PCM signed 24-bit big-endian โ encode
X, decodeX - PCM signed 24-bit little-endian โ encode
X, decodeX - PCM signed 32-bit big-endian โ encode
X, decodeX - PCM signed 32-bit little-endian โ encode
X, decodeX - PCM signed 16/20/24-bit big-endian in MPEG-TS โ decode
Xonly. So specific, love that for it ๐ - PCM unsigned 8-bit โ encode
X, decodeX - PCM unsigned 16-bit big-endian โ encode
X, decodeX - PCM unsigned 16-bit little-endian โ encode
X, decodeX - PCM unsigned 24-bit big-endian โ encode
X, decodeX - PCM unsigned 24-bit little-endian โ encode
X, decodeX - PCM unsigned 32-bit big-endian โ encode
X, decodeX - PCM unsigned 32-bit little-endian โ encode
X, decodeX - PCM SGA โ decode
Xonly - QCELP / PureVoice โ decode
Xonly - QDesign Music Codec 1 โ decode
Xonly - QDesign Music Codec 2 โ decode
Xonly. Page note: There are still some distortions. ๐ (real of them to admit it) - RealAudio 1.0 (14.4K) โ encode
X, decodeX. Page note: Real 14400 bit/s codec - RealAudio 2.0 (28.8K) โ decode
Xonly. Page note: Real 28800 bit/s codec - RealAudio 3.0 (dnet) โ encode
IX, decodeX. Page note: Real low bitrate AC-3 codec - RealAudio Lossless โ decode
Xonly - RealAudio SIPR / ACELP.NET โ decode
Xonly - RK Audio (RKA) โ decode
Xonly - SBC (low-complexity subband codec) โ encode
X, decodeX. Page note: Used in Bluetooth A2DP ๐ฆ - Shorten โ decode
Xonly - Sierra VMD audio โ decode
Xonly. Page note: Used in Sierra VMD files. - Smacker audio โ decode
Xonly - SMPTE 302M AES3 audio โ encode
X, decodeX - Sonic โ encode
X, decodeX. Page note: experimental codec โ๏ธ - Sonic lossless โ encode
X, decodeX. Page note: experimental codec - Speex โ encode
E, decodeEX. Page note: supported through external library libspeex - TAK (Tom's lossless Audio Kompressor) โ decode
Xonly - True Audio (TTA) โ encode
X, decodeX - TrueHD โ encode
X, decodeX. Page note: Used in HD-DVD and Blu-Ray discs. - TwinVQ (VQF flavor) โ decode
Xonly - VIMA โ decode
Xonly. Page note: Used in LucasArts SMUSH animations. - ViewQuest VQC โ decode
Xonly - Vorbis โ encode
E, decodeX. Page note: A native but very primitive encoder exists. ๐ - Voxware MetaSound โ decode
Xonly - Waveform Archiver โ decode
Xonly - WavPack โ encode
X, decodeX - Westwood Audio (SND1) โ decode
Xonly - Windows Media Audio 1 โ encode
X, decodeX - Windows Media Audio 2 โ encode
X, decodeX - Windows Media Audio Lossless โ decode
Xonly - Windows Media Audio Pro โ decode
Xonly - Windows Media Audio Voice โ decode
Xonly - Xbox Media Audio 1 โ decode
Xonly - Xbox Media Audio 2 โ decode
Xonly
Now the legend, because the letters are doing a lot of heavy lifting here:
Xmeans that the feature in that column (encoding / decoding) is supported.Emeans that support is provided through an external library.Imeans that an integer-only version is available, too (ensures high performance on systems without hardware floating point support).
๐ฌ Subtitle Formats ๐ฌ
Columns go Muxing, Demuxing, Encoding, Decoding โ in that order, every line, no cap.
- 3GPP Timed Text โ encode
X, decodeX(muxing and demuxing stay blank) - AQTitle โ demux
X, decodeX - DVB โ mux
X, demuxX, encodeX, decodeX. Full house, icon behavior ๐ - DVB teletext โ demux
X, decodeE - DVD โ mux
X, demuxX, encodeX, decodeX - JACOsub โ mux
X, demuxX, decodeX - MicroDVD โ mux
X, demuxX, decodeX - MPL2 โ demux
X, decodeX - MPsub (MPlayer) โ demux
X, decodeX - PGS โ decode
Xonly - PJS (Phoenix) โ demux
X, decodeX - RealText โ demux
X, decodeX - SAMI โ demux
X, decodeX - Spruce format (STL) โ demux
X, decodeX - SSA/ASS โ mux
X, demuxX, encodeX, decodeX - SubRip (SRT) โ mux
X, demuxX, encodeX, decodeX - SubViewer v1 โ demux
X, decodeX - SubViewer โ demux
X, decodeX - TED Talks captions โ demux
X, decodeX - TTML โ mux
X, encodeX(demuxing and decoding stay blank) - VobSub (IDX+SUB) โ demux
X, decodeX - VPlayer โ demux
X, decodeX - WebVTT โ mux
X, demuxX, encodeX, decodeX - XSUB โ encode
X, decodeX
Tiny legend again, because consistency:
Xmeans that the feature is supported.Emeans that support is provided through an external library.
๐ Network Protocols ๐
Name : Support. That's the whole vibe.
- AMQP โ
E - file โ
X - FTP โ
X - Gopher โ
X - Gophers โ
X - HLS โ
X - HTTP โ
X - HTTPS โ
X - Icecast โ
X - MMSH โ
X - MMST โ
X - pipe โ
X - Pro-MPEG FEC โ
X - RTMP โ
X - RTMPE โ
X - RTMPS โ
X - RTMPT โ
X - RTMPTE โ
X - RTMPTS โ
X - RTP โ
X - SAMBA โ
E - SCTP โ
X - SFTP โ
E - TCP โ
X - TLS โ
X - UDP โ
X - ZMQ โ
E
And the legend, one more time:
Xmeans that the protocol is supported.Emeans that support is provided through an external library.
๐๏ธ Input/Output Devices ๐๏ธ
Two columns here: Input and Output. If a cell's empty in the original, it just doesn't get a X, bestie.
- ALSA โ input
X, outputX - BKTR โ input
X(no output) - caca โ output
X(no input) - DV1394 โ input
X - Lavfi virtual device โ input
X - Linux framebuffer โ input
X, outputX - JACK โ input
X - LIBCDIO โ input
X - LIBDC1394 โ input
X - OpenAL โ input
X - OpenGL โ output
X - OSS โ input
X, outputX - PulseAudio โ input
X, outputX - SDL โ output
X - Video4Linux2 โ input
X, outputX - VfW capture โ input
X - X11 grabbing โ input
X - Win32 grabbing โ input
X
Legend:
Xmeans that input/output is supported.
โฑ๏ธ Timecode โฑ๏ธ
Read and Write, and honestly it's X's across the board, we love a clean sweep ๐ฅ
- AVI โ read
X, writeX - DV โ read
X, writeX - GXF โ read
X, writeX - MOV โ read
X, writeX - MPEG1/2 โ read
X, writeX - MXF โ read
X, writeX
๐ SEE ALSO ๐
Go read your sisters, bestie, they're all iconic:
ffprobe(1)ffmpeg(1)ffplay(1)ffmpeg-utils(1)ffmpeg-scaler(1)ffmpeg-resampler(1)ffmpeg-codecs(1)ffmpeg-bitstream-filters(1)ffmpeg-formats(1)ffmpeg-devices(1)ffmpeg-protocols(1)ffmpeg-filters(1)
๐ AUTHORS ๐
The FFmpeg developers. That's the credit line, periodt ๐ซถ
For details about the authorship, see the Git history of the project (https://git.ffmpeg.org/ffmpeg), e.g. by typing the command git log in the FFmpeg source directory, or browsing the online repository at https://git.ffmpeg.org/ffmpeg.
Maintainers for the specific components are listed in the file MAINTAINERS in the source code tree.
And that's a wrap, babe ๐ โ the footer is the source/version-plus-date line that closes out FFPROBE-ALL(1), and you just read the whole thing, every last X. Genuinely obsessed with you rn ๐
โจ
๐ฆ where this page comes from
- alpine 3.24: ffmpeg-doc 8.1.3-r0 ยท GPL-2.0-or-later AND LGPL-2.1-or-later
- nixos 26.05: ffmpeg 8.1.3
- nixos 26.05: ffmpeg-headless 8.1.3
- ๐ girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms