FFPLAY-ALL(1)
โจ NAME โจ
ffplay โ the FFplay media player, bestie ๐ (yes that's the whole name section, she's lowkey humble like that)
๐ SYNOPSIS ๐
ffplay [options] [input_url]
๐ฆ DESCRIPTION ๐ฆ
Okay so picture this: FFplay is a very simple and portable media player that runs on the FFmpeg libraries plus the SDL library. That's the whole vibe. โจ
And likeโฆ its main character job? It's mostly used as a testbed for all the various FFmpeg APIs. So it's less "download this to watch your movies" and more "the devs use it to poke at stuff." Ngl it still slays at playing media tho ๐
๐ธ OPTIONS ๐ธ
So every numerical option here โ unless it says otherwise โ accepts a string that represents a number as input, and that string can be followed by one of the SI unit prefixes. Examples given: 'K', 'M', or 'G'. Cute, right? ๐
Now if you append 'i' to that SI unit prefix, the whole prefix gets interpreted as a unit prefix for binary multiples, which are based on powers of 1024 instead of powers of 1000. Math girlie behavior fr fr. And if you append 'B' to the SI unit prefix, it multiplies the value by 8. So this is how you get suffixes like 'KB', 'MiB', 'G' and 'B' as number suffixes. Obsessed with the flexibility honestly ๐ซถ
Options that don't take arguments are boolean options, and they set the corresponding value to true. Want it false? Just prefix the option name with "no". So using -nofoo will set the boolean option named "foo" to false. Iconic shortcut, no cap ๐
Options that do take arguments support a special syntax where the argument you gave on the command line is interpreted as a path to the file the actual argument value gets loaded from. To use this feature, add a forward slash / immediately before the option name (after the leading dash). Like so:
ffmpeg -i INPUT -/filter:v filter.script OUTPUT
That will load a filtergraph description from the file named filter.script. She's reading from a file, your honor ๐โจ
๐ Stream specifiers ๐
Some options are applied per-stream โ think bitrate or codec. Stream specifiers are how you precisely specify which stream(s) a given option belongs to. Vibe check on your streams, basically ๐
A stream specifier is a string that's generally appended to the option name and separated from it by a colon. Example: -codec:a:1 ac3 contains the "a:1" stream specifier, which matches the second audio stream. So it would select the ac3 codec for the second audio stream. Slay ๐ฏ
A stream specifier can match several streams too, so the option gets applied to all of them. Example: the stream specifier in -b:a 128k matches all audio streams.
An empty stream specifier matches all streams. For example, -codec copy or -codec: copy would copy all the streams without reencoding. Copy queen ๐
Possible forms of stream specifiers are:
stream_indexโ Matches the stream with this index. Example:-threads:1 4would set the thread count for the second stream to 4. And ifstream_indexis used as an additional stream specifier (peep below), then it selects stream numberstream_indexfrom the matching streams. Stream numbering is based on the order of the streams as detected by libavformat โ except when a stream group specifier or program ID is also specified. In that case it's based on the ordering of the streams in the group or program. Order matters, bestie ๐งstream_type[:additional_stream_specifier]โstream_typeis one of the 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. 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. Andgroup_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. ๐#stream_idori:stream_idโ Match the stream by stream id (like a PID in an MPEG-TS container, iykyk).m:key[:value]โ Matches streams with the metadata tagkeyhaving the specifiedvalue. Ifvalueisn't given, it matches streams that contain the given tag with any value. Heads up: the colon character':'inkeyorvalueneeds to be backslash-escaped. ๐disp: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'+'. Go off ๐uโ 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.
Okay small important note: in ffmpeg, matching by metadata will only work properly for input files. Just so you know, bestie ๐ญ
๐ Generic options ๐
These options are shared amongst the ff* tools. Family sharing, we love to see it ๐ซถ
-L,-licenseโ Show license. ๐-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.
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. The whole buffet ๐decoder=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. โจ-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 to libavcodec.
Little note: the term 'codec' is used throughout this documentation as a shortcut for what is more correctly called a media bitstream format. Precision, bestie ๐
-decodersโ Show available decoders.-encodersโ Show all available encoders.-bsfsโ Show available bitstream filters.-protocolsโ Show available protocols.-filtersโ Show available libavfilter filters.-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. ๐ (my personal fave, obviously)-sourcesdevice[,opt1=val1[,opt2=val2]...]โ Show autodetected sources of the input device. Some devices may provide system-dependent source names that cannot be autodetected. And the returned list cannot be assumed to be always complete. Ngl that's just how it is ๐ญ
ffmpeg -sources pulse,server=192.168.0.4
-sinksdevice[,opt1=val1[,opt2=val2]...]โ Show autodetected sinks of the output device. Some devices may provide system-dependent sink names that cannot be autodetected. Same deal: the returned list cannot be assumed to be always complete. ๐ซถ
ffmpeg -sinks pulse,server=192.168.0.4
-loglevel [flags+]loglevelor-v [flags+]loglevelโ Set logging level and flags used by the library. Let's control the chatter ๐ฌ
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. โฐ
Flags can also be used alone by adding a '+'/'-' prefix to set/reset a single flag without affecting other flags or changing loglevel. And when setting both flags and loglevel, a '+' separator is expected between the last flags value and before loglevel. ๐
loglevel is a string or a number containing one of the following values:
quiet,-8โ Show nothing at all; be silent. ๐คซpanic,0โ Only show fatal errors which could lead the process to crash, such as an assertion failure. Heads up: this is not currently used for anything.fatal,8โ Only show fatal errors. These are errors after which the process absolutely cannot continue. ๐error,16โ Show all errors, including ones which can be recovered from.warning,24โ Show all warnings and errors. Any message related to possibly incorrect or unexpected events will be shown.info,32โ Show informative messages during processing. This is in addition to warnings and errors. This is the default value. ๐verbose,40โ Same as"info", except more verbose. She's chatty.debug,48โ Show everything, including debugging information.trace,56โ (that's it, that's the entire description, she said what she said)
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
okay so another example that enables repeated log output without affecting the current state of the level prefix flag or loglevel:
ffmpeg [...] -loglevel +repeat
By default the program logs to stderr. If coloring is supported by the terminal, colors are used to mark errors and warnings. Log coloring can be disabled by setting the environment variable AV_LOG_FORCE_NOCOLOR, or can be forced by setting the environment variable AV_LOG_FORCE_COLOR.
-reportโ Dump the full command line and log output to a file namedprogram-YYYYMMDD-HHMMSS.login the current directory. This file can be useful for bug reports. 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, these options will affect the report; option values must be escaped if they contain special characters or the options delimiter : (see the โQuoting and escapingโ section in the ffmpeg-utils manual).
The following options are recognized:
fileโ set the file name to use for the report;%pis expanded to the name of the program,%tis expanded to a timestamp,%%is expanded to a plain%levelโ 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 (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 will not appear in the report.
-hide_bannerโ Suppress printing the banner.
All FFmpeg tools will normally show a copyright notice, build options and library versions. This option can be used to suppress printing this information.
-cpuflags flags (global)โ Allows setting and clearing cpu flags. This option is intended for testing. Do not use it unless you know what you're doing.
ffmpeg -cpuflags -sse+mmx ...
ffmpeg -cpuflags mmx ...
ffmpeg -cpuflags 0 ...
Possible flags for this option are:
x86โmmx,mmxext,sse,sse2,sse2slow,sse3,sse3slow,ssse3,atom,sse4.1,sse4.2,avx,avx2,xop,fma3,fma4,3dnow,3dnowext,bmi1,bmi2,cmovARMโarmv5te,armv6,armv6t2,vfp,vfpv3,neon,setendAArch64โarmv8,vfp,neonPowerPCโaltivec- Specific Processors โ
pentium2,pentium3,pentium4,k6,k62,athlon,athlonxp,k8
-cpucount count (global)โ Override detection of CPU count. This option is intended for testing. Do not use it unless you know what you're doing.
ffmpeg -cpucount 2
-max_alloc bytesโ Set 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 if you do not 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. To see the list of available AVOptions, use the -help option. They are separated into two categories:
genericโ These options can be set for any container, codec or device. Generic options are listed underAVFormatContextoptions for containers/devices and underAVCodecContextoptions for codecs.privateโ These options are specific to the given container, device or codec. Private options are listed under their corresponding containers/devices/codecs.
For example, to write an ID3v2.3 header instead of a default ID3v2.4 to 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, and thus a stream specifier should be attached 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 the above 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 absolute index of the output stream.
Note: the-nooptionsyntax cannot be used for boolean AVOptions, use-option 0/-option 1.
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 Main options ๐
-x widthโ Force displayed width.-y heightโ Force displayed height.-fsโ Start in fullscreen mode.-anโ Disable audio.-vnโ Disable video.-snโ Disable subtitles.-ss posโ Seek to pos. Note that in most formats it is not possible to seek exactly, so ffplay will seek to the nearest seek point to pos.
pos must be a time duration specification, see the Time duration section in the ffmpeg-utils(1) manual.
-t durationโ Play duration seconds of audio/video.
duration must be a time duration specification, see the Time duration section in the ffmpeg-utils(1) manual.
-bytesโ Seek by bytes.-seek_intervalโ Set custom interval, in seconds, for seeking using left/right keys. Default is 10 seconds.-nodispโ Disable graphical display.-noborderโ Borderless window.-alwaysontopโ Window always on top. Available on: X11 with SDL >= 2.0.5, Windows SDL >= 2.0.6.-volumeโ Set the startup volume.0means silence,100means no volume reduction or amplification. Negative values are treated as0, values above100are treated as100.-f fmtโ Force format.-window_title titleโ Set window title (default is the input filename).-left titleโ Set the x position for the left of the window (default is a centered window).-top titleโ Set the y position for the top of the window (default is a centered window).-loop numberโ Loops movie playback number times.0means forever.-showmode modeโ Set the show mode to use. Available values for mode are:0,videoโ show video1,wavesโ show audio waves2,rdftโ show audio frequency band using RDFT ((Inverse) Real Discrete Fourier Transform)
Default value is video; if video is not present or cannot be played, rdft is automatically selected.
You can interactively cycle through the available show modes by pressing the key w.
-vf filtergraphโ Create the filtergraph specified by filtergraph and use it to filter the video stream.
filtergraph is a description of the filtergraph to apply to the stream, and must have a single video input and a single video output. In the filtergraph, the input is associated to the label "in", and the output to the label "out". See the ffmpeg-filters manual for more information about the filtergraph syntax.
You can specify this parameter multiple times and cycle through the specified filtergraphs along with the show modes by pressing the key w.
-af filtergraphโ filtergraph is a description of the filtergraph to apply to the input audio. Use the option-filtersto show all the available filters (including sources and sinks).-i input_urlโ Read input_url.
๐ Advanced options ๐
-statsโ Print several playback statistics, in particular show the stream duration, the codec parameters, the current position in the stream and the audio/video synchronisation drift. It is shown by default, unless the log level is lower thaninfo. Its display can be forced by manually specifying this option. To disable it, you need to specify-nostats.-fastโ Non-spec-compliant optimizations.-genptsโ Generate pts.-sync typeโ Set the master clock to audio (type=audio), video (type=video) or external (type=ext). Default is audio. The master clock is used to control audio-video synchronization. Most media players use audio as master clock, but in some cases (streaming or high quality broadcast) it is necessary to change that. This option is mainly used for debugging purposes.-ast audio_stream_specifierโ Select the desired audio stream using the given stream specifier. The stream specifiers are described in the Stream specifiers chapter. If this option is not specified, the"best"audio stream is selected in the program of the already selected video stream.-vst video_stream_specifierโ Select the desired video stream using the given stream specifier. The stream specifiers are described in the Stream specifiers chapter. If this option is not specified, the"best"video stream is selected.-sst subtitle_stream_specifierโ Select the desired subtitle stream using the given stream specifier. The stream specifiers are described in the Stream specifiers chapter. If this option is not specified, the"best"subtitle stream is selected in the program of the already selected video or audio stream.-autoexitโ Exit when video is done playing.-exitonkeydownโ Exit if any key is pressed.-exitonmousedownโ Exit if any mouse button is pressed.-codec:media_specifier codec_nameโ Force a specific decoder implementation for the stream identified by media_specifier, which can assume the valuesa(audio),v(video), andssubtitle.-acodec codec_nameโ Force a specific audio decoder.-vcodec codec_nameโ Force a specific video decoder.-scodec codec_nameโ Force a specific subtitle decoder.-autorotateโ Automatically rotate the video according to file metadata. Enabled by default, use-noautorotateto disable it.-framedropโ bestie, this one just drops video frames when the video's out of sync โจ It's on by default if the master clock isn't set to video. Wanna force frame dropping for all master clock sources? Use this option. Wanna turn it off?-noframedrop. Slay.-infbufโ do not limit the input buffer size โ read as much data as possible from the input, ASAP ๐ This is enabled by default for realtime streams, where data might get dropped if it's not read in time. Use this option to get infinite buffers for all inputs, or-noinfbufto disable it. iykyk.-filter_threadsnb_threads โ tells you how many threads get used to process a filter pipeline ๐งต Every pipeline spawns a thread pool with this many threads available for parallel processing. Default is0, which literally means the thread count is decided by the number of available CPUs. main character scheduling fr.-enable_vulkanโ use the vulkan renderer instead of the SDL builtin renderer ๐ฆ Depends onlibplacebo. no cap.-vulkan_paramsโ vulkan configuration, given as a list ofkey=valuepairs separated by":"๐-hwaccelโ use HW accelerated decoding ๐ฅ Turning this on will enable the vulkan renderer automatically. it's giving efficiency.-video_bgpattern โ sets the video background pattern used for transparent videos ๐ผ๏ธ For solid color patterns you can use the color name or color code as specified in the Color section in theffmpeg-utils(1)manual. You can also use the special"tiles"keyword for a checker board style pattern โ and that's also the default. The"none"pattern does rendering without alpha blending, effectively ignoring the alpha channel. periodt.
๐ While playing ๐
okay so this is the fun part โ the keyboard is literally your bestie now, here's every binding ๐
q,ESCโ quit. bye bestie ๐fโ toggle full screen ๐ฅ๏ธp,SPCโ pause โธ๏ธmโ toggle mute ๐9,0and/,*โ decrease and increase volume respectively ๐ (yes, both pairs do the same thing, iconic)aโ cycle audio channel in the current program ๐งvโ cycle video channel ๐บtโ cycle subtitle channel in the current program ๐ฌcโ cycle program ๐wโ cycle video filters or show modes ๐sโ step to the next frame โญ๏ธ Pauses if the stream isn't already paused, steps to the next video frame, and pauses. so satisfying ngl.- left/right โ seek backward/forward by 10 seconds, or a custom interval if
-seek_intervalis set โชโฉ - down/up โ seek backward/forward 1 minute โฑ๏ธ
- page down/page up โ seek to previous/next chapter, or backward/forward 10 minutes if there's no chapters ๐
- right mouse click โ seek to percentage in file corresponding to fraction of width ๐ฑ๏ธ (yes it maps your click position to the file, lowkey genius)
- left mouse double-click โ toggle full screen ๐ฑ๏ธ๐ฑ๏ธ
๐ SYNTAX ๐
This section documents the syntax and formats employed by the FFmpeg libraries and tools. buckle up, it's grammar class but make it cute ๐
๐ง Quoting and escaping ๐ง
FFmpeg adopts the following quoting and escaping mechanism, unless it's explicitly specified otherwise. The rules, bestie:
'and\are special characters (used for quoting and escaping respectively) ๐ On top of those, 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. annoying but true ๐ญ - Leading and trailing whitespaces, unless escaped or quoted, are removed from the parsed string โ๏ธ
Heads up: you may need to add a second level of escaping when using the command line or a script, and that depends on the syntax of the adopted shell language. lowkey the villain of the whole system.
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 ๐
The tool tools/ffescape in the FFmpeg source tree can be used to automatically quote or escape a string in a script ๐ ๏ธ
โจ Examples โจ
- 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๏ธ Date ๐๏ธ
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 โฐ
Time is local time unless Z is appended, in which case it's interpreted as UTC. If the year-month-day part isn't specified, it takes the current year-month-day ๐ฆ
โณ Time duration โณ
There are two accepted syntaxes for expressing time duration, bestie:
[-][<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 the decimal value for SS ๐
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 ๐ซ
In both expressions, the optional - indicates a negative duration.
๐ธ Examples ๐ธ
The following examples are all valid time duration:
55โ 55 seconds0.2โ 0.2 seconds200msโ 200 milliseconds, that's0.2s200000usโ 200000 microseconds, that's0.2s12:03:45โ 12 hours, 03 minutes and 45 seconds23.189โ 23.189 seconds
๐ผ๏ธ Video size ๐ผ๏ธ
Specify the size of the sourced video โ it may be a string of the form widthx*height*, or the name of a size abbreviation ๐
The following abbreviations are recognized:
ntscโ720x480palโ720x576qntscโ352x240qpalโ352x288sntscโ640x480spalโ768x576filmโ352x240ntsc-filmโ352x240sqcifโ128x96qcifโ176x144cifโ352x2884cifโ704x57616cifโ1408x1152qqvgaโ160x120qvgaโ320x240vgaโ640x480svgaโ800x600xgaโ1024x768uxgaโ1600x1200qxgaโ2048x1536sxgaโ1280x1024qsxgaโ2560x2048hsxgaโ5120x4096wvgaโ852x480wxgaโ1366x768wsxgaโ1600x1024wuxgaโ1920x1200woxgaโ2560x1600wqsxgaโ3200x2048wquxgaโ3840x2400whsxgaโ6400x4096whuxgaโ7680x4800cgaโ320x200egaโ640x350hd480โ852x480hd720โ1280x720hd1080โ1920x10802kโ2048x10802kflatโ1998x10802kscopeโ2048x8584kโ4096x21604kflatโ3996x21604kscopeโ4096x1716nhdโ640x360hqvgaโ240x160wqvgaโ400x240fwqvgaโ432x240hvgaโ480x320qhdโ960x5402kdciโ2048x10804kdciโ4096x2160uhd2160โ3840x2160uhd4320โ7680x4320
๐๏ธ Video rate ๐๏ธ
Specify the frame rate of a video, expressed as the number of frames 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 ๐ซ
The following abbreviations are recognized:
ntscโ30000/1001palโ25/1qntscโ30000/1001qpalโ25/1sntscโ30000/1001spalโ25/1filmโ24/1ntsc-filmโ24000/1001
โ๏ธ Ratio โ๏ธ
A ratio can be expressed as an expression, or in the form numerator:denominator ๐
Careful bestie โ a ratio with an infinite (1/0) or negative value is considered valid, so you should check on the returned value if you wanna exclude those values. ๐
The undefined value can be expressed using the "0:0" string.
๐จ Color ๐จ
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 ๐
The alpha component may be a string composed by "0x" followed by a 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 isn't specified, then 0xff is assumed ๐
The string random will result in a random color ๐ฒ
The following names of colors are recognized:
AliceBlueโ0xF0F8FFAntiqueWhiteโ0xFAEBD7Aquaโ0x00FFFFAquamarineโ0x7FFFD4Azureโ0xF0FFFFBeigeโ0xF5F5DCBisqueโ0xFFE4C4Blackโ0x000000BlanchedAlmondโ0xFFEBCDBlueโ0x0000FFBlueVioletโ0x8A2BE2Brownโ0xA52A2ABurlyWoodโ0xDEB887CadetBlueโ0x5F9EA0Chartreuseโ0x7FFF00Chocolateโ0xD2691ECoralโ0xFF7F50CornflowerBlueโ0x6495EDCornsilkโ0xFFF8DCCrimsonโ0xDC143CCyanโ0x00FFFFDarkBlueโ0x00008BDarkCyanโ0x008B8BDarkGoldenRodโ0xB8860BDarkGrayโ0xA9A9A9DarkGreenโ0x006400DarkKhakiโ0xBDB76BDarkMagentaโ0x8B008BDarkOliveGreenโ0x556B2FDarkorangeโ0xFF8C00DarkOrchidโ0x9932CCDarkRedโ0x8B0000DarkSalmonโ0xE9967ADarkSeaGreenโ0x8FBC8FDarkSlateBlueโ0x483D8BDarkSlateGrayโ0x2F4F4FDarkTurquoiseโ0x00CED1DarkVioletโ0x9400D3DeepPinkโ0xFF1493DeepSkyBlueโ0x00BFFFDimGrayโ0x696969DodgerBlueโ0x1E90FFFireBrickโ0xB22222FloralWhiteโ0xFFFAF0ForestGreenโ0x228B22Fuchsiaโ0xFF00FFGainsboroโ0xDCDCDCGhostWhiteโ0xF8F8FFGoldโ0xFFD700GoldenRodโ0xDAA520Grayโ0x808080Greenโ0x008000GreenYellowโ0xADFF2FHoneyDewโ0xF0FFF0HotPinkโ0xFF69B4IndianRedโ0xCD5C5CLavenderBlushโ0xFFF0F5LawnGreenโ0x7CFC00LemonChiffonโ0xFFFACDLightBlueโ0xADD8E6LightCoralโ0xF08080LightCyanโ0xE0FFFFLightGoldenRodYellowโ0xFAFAD2LightGreenโ0x90EE90LightGreyโ0xD3D3D3LightPinkโ0xFFB6C1๐LightSalmonโ0xFFA07ALightSeaGreenโ0x20B2AALightSkyBlueโ0x87CEFALightSlateGrayโ0x778899LightSteelBlueโ0xB0C4DELightYellowโ0xFFFFE0Limeโ0x00FF00LimeGreenโ0x32CD32Linenโ0xFAF0E6Magentaโ0xFF00FFMaroonโ0x800000MediumAquaMarineโ0x66CDAAMediumBlueโ0x0000CDMediumOrchidโ0xBA55D3MediumPurpleโ0x9370D8MediumSeaGreenโ0x3CB371MediumSlateBlueโ0x7B68EEMediumSpringGreenโ0x00FA9AMediumTurquoiseโ0x48D1CCMediumVioletRedโ0xC71585MidnightBlueโ0x191970MintCreamโ0xF5FFFAMistyRoseโ0xFFE4E1Moccasinโ0xFFE4B5NavajoWhiteโ0xFFDEADNavyโ0x000080OldLaceโ0xFDF5E6Oliveโ0x808000OliveDrabโ0x6B8E23Orangeโ0xFFA500OrangeRedโ0xFF4500Orchidโ0xDA70D6PaleGoldenRodโ0xEEE8AAPaleGreenโ0x98FB98PaleTurquoiseโ0xAFEEEEPaleVioletRedโ0xD87093PapayaWhipโ0xFFEFD5PeachPuffโ0xFFDAB9Peruโ0xCD853FPinkโ0xFFC0CB๐Plumโ0xDDA0DDPowderBlueโ0xB0E0E6Purpleโ0x800080Redโ0xFF0000RosyBrownโ0xBC8F8FRoyalBlueโ0x4169E1SaddleBrownโ0x8B4513Salmonโ0xFA8072SandyBrownโ0xF4A460SeaGreenโ0x2E8B57SeaShellโ0xFFF5EESiennaโ0xA0522DSilverโ0xC0C0C0SkyBlueโ0x87CEEBSlateBlueโ0x6A5ACDSlateGrayโ0x708090Snowโ0xFFFAFAโ๏ธSpringGreenโ0x00FF7FSteelBlueโ0x4682B4Tanโ0xD2B48CTealโ0x008080Thistleโ0xD8BFD8Tomatoโ0xFF6347๐Turquoiseโ0x40E0D0Violetโ0xEE82EEWheatโ0xF5DEB3Whiteโ0xFFFFFFWhiteSmokeโ0xF5F5F5Yellowโ0xFFFF00YellowGreenโ0x9ACD32
๐ง Channel Layout ๐ง
Okay bestie, real talk โ a channel layout is just the map of where all the audio channels are placed in space in a multi-channel stream. Like, which speaker goes where in your room. FFmpeg has its own special syntax for saying all that, and it's honestly kind of a vibe once you get it. ๐ฆ
Individual channels
Every channel has an id, and here's the whole guest list:
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 ๐โจ
You don't have to spell everything out yourself โ these identifiers are the pre-made fits. Just drop the name and you're done:
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
Not me pointing out that 6.1 shows up twice with two different compositions โ that's literally what the source says, so I'm keeping both. Not a typo on my end, bestie, I promise. ๐
Custom layouts ๐ ๏ธโจ
A custom channel layout is just a sequence of terms, glued together with +. 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.)
Standard layouts, the short way
You can also specify a standard channel layout with any of these:
- 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, yielding the default channel layout for that number of channels (see the functionav_channel_layout_default). Note that not all channel counts have a default layout โ vibe check failed on those, sorry. ๐ญ - a number of channels, in decimal, followed by
C, yielding an unknown channel layout with the specified number of channels. Note that not all channel layout specification strings support unknown channel layouts. - a channel layout mask, in hexadecimal starting with
0x(see theAV_CH_*macros inlibavutil/channel_layout.h.
โ ๏ธ History lesson, and it's giving "back in my day": before libavutil version 53 the trailing charactercto specify a number of channels was optional, but now it is required. Meanwhile a channel layout mask can also be specified as a decimal number (if and only if not followed bycorC). So yes, thecis mandatory now. Periodt.
Also, go check out the function av_channel_layout_from_string defined in libavutil/channel_layout.h. ๐
โจ EXPRESSION EVALUATION โจ
Okay so when FFmpeg needs to do math, it uses its own little internal formula evaluator, implemented through the libavutil/eval.h interface. Yes bestie, it has a whole calculator built in ๐
An expression may contain unary operators, binary operators, constants, and functions. It's giving math class but make it slay.
Two expressions expr1 and expr2 can be combined to form another expression "expr1;expr2". expr1 and expr2 are evaluated in turn, and the new expression evaluates to the value of expr2. So like, the second one is the main character 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. They can be accessed using the "ld" and "st" functions with an index argument varying from 0 to 9 to specify which internal variable to access. Little numbered lockers, basically ๐
๐งฎ The Functions ๐งฎ
The following functions are available:
abs(x)
Compute absolute value of x. No more negative vibes โจ
acos(x)
Compute arccosine of x.
asin(x)
Compute arcsine of x.
atan(x)
Compute arctangent of x.
atan2(y, x)
Compute principal value of the arc tangent of y/x.
between(x, min, max)
Return 1 if x is greater than or equal to min and lesser than or equal to max, 0 otherwise. A true vibe check ๐ฆ
bitand(x, y) and bitor(x, y)
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). ๐ญ Precision loss is not the moment, fr fr.
ceil(expr)
Round the value of expression expr upwards to the nearest integer. For example, "ceil(1.5)" is "2.0".
clip(x, min, max)
Return the value of x clipped between min and max. Keeping it in range, periodt ๐
cos(x)
Compute cosine of x.
cosh(x)
Compute hyperbolic cosine of x.
eq(x, y)
Return 1 if x and y are equivalent, 0 otherwise.
exp(x)
Compute exponential of x (with base "e", the Euler's number).
floor(expr)
Round the value of expression expr downwards to the nearest integer. For example, "floor(-1.5)" is "-2.0".
gauss(x)
Compute Gauss function of x, corresponding to "exp(-x*x/2) / sqrt(2*PI)".
gcd(x, y)
Return the greatest common divisor of x and y. If both x and y are 0 or either or both are less than zero then behavior is undefined. ๐ So like, don't do that.
gt(x, y)
Return 1 if x is greater than y, 0 otherwise.
gte(x, y)
Return 1 if x is greater than or equal to y, 0 otherwise.
hypot(x, y)
This function is similar to the C function with the same name; it returns "sqrt(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. Pythagoras could never ๐
if(x, y)
Evaluate x, and if the result is non-zero return the result of the evaluation of y, return 0 otherwise.
if(x, y, z)
Evaluate x, and if the result is non-zero return the evaluation result of y, otherwise the evaluation result of z.
ifnot(x, y)
Evaluate x, and if the result is zero return the result of the evaluation of y, return 0 otherwise.
ifnot(x, y, z)
Evaluate x, and if the result is zero return the evaluation result of y, otherwise the evaluation result of z.
isinf(x)
Return 1.0 if x is +/-INFINITY, 0.0 otherwise.
isnan(x)
Return 1.0 if x is NAN, 0.0 otherwise.
ld(idx)
Load the value of the internal variable with index idx, which was previously stored with st(idx, expr). The function returns the loaded value.
lerp(x, y, z)
Return linear interpolation between x and y by amount of z.
log(x)
Compute natural logarithm of x.
lt(x, y)
Return 1 if x is lesser than y, 0 otherwise.
lte(x, y)
Return 1 if x is lesser than or equal to y, 0 otherwise.
max(x, y)
Return the maximum between x and y.
min(x, y)
Return the minimum between x and y.
mod(x, y)
Compute the remainder of division of x by y.
not(expr)
Return 1.0 if expr is zero, 0.0 otherwise.
pow(x, y)
Compute the power of x elevated y, it is equivalent to "(x)^(y)".
print(t) and print(t, l)
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. Little peek at what's going on inside ๐
random(idx)
Return a pseudo random value between 0.0 and 1.0. idx is the index of the internal variable used to save the seed/state, which can be previously stored with st(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)
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 with st(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)
Find an input value for which the function represented by expr with argument ld(0) is 0 in the interval 0..max.
The expression in expr must denote a continuous function or the result is undefined. โ ๏ธ Not continuous? Not our problem, but also it is your problem.
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)
Round the value of expression expr to the nearest integer. For example, "round(1.5)" is "2.0".
sgn(x)
Compute sign of x.
sin(x)
Compute sine of x.
sinh(x)
Compute hyperbolic sine of x.
sqrt(expr)
Compute the square root of expr. This is equivalent to "(expr)^.5".
squish(x)
Compute expression "1/(1 + exp(4*x))". Love that name honestly, iconic ๐ธ
st(idx, expr)
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 from 0 to 9. 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. So no passing notes between expressions, bestie, they don't talk ๐ญ
tan(x)
Compute tangent of x.
tanh(x)
Compute hyperbolic tangent of x.
taylor(expr, x) and taylor(expr, x, idx)
Evaluate a Taylor series at x, given an expression representing the ld(idx)-th derivative of a function at 0.
When the series does not converge the result is undefined.
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.
time(0)
Return the current (wallclock) time in seconds. Clock check โฐ
trunc(expr)
Round the value of expression expr towards zero to the nearest integer. For example, "trunc(-1.5)" is "-1.0".
while(cond, expr)
Evaluate expression expr while the expression cond is non-zero, and returns the value of the last expr evaluation, or NAN if cond was always false.
๐ The Constants ๐
The following constants are available:
PIโ area of the unit disc, approximately 3.14Eโexp(1)(Euler's number), approximately 2.718PHIโ golden ratio(1+sqrt(5))/2, approximately 1.618
๐ Truthy Business ๐
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 off, build your own toolkit ๐ซถ
๐ง Unit Prefixes ๐ง
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.
The list of available International System prefixes follows, with indication of the corresponding powers of 10 and of 2.
yโ 10^-24 / 2^-80zโ 10^-21 / 2^-70aโ 10^-18 / 2^-60fโ 10^-15 / 2^-50pโ 10^-12 / 2^-40nโ 10^-9 / 2^-30uโ 10^-6 / 2^-20mโ 10^-3 / 2^-10cโ 10^-2dโ 10^-1hโ 10^2kโ 10^3 / 2^10Kโ 10^3 / 2^10Mโ 10^6 / 2^20Gโ 10^9 / 2^30Tโ 10^12 / 2^40Pโ 10^15 / 2^50Eโ 10^18 / 2^60Zโ 10^21 / 2^70Yโ 10^24 / 2^80
๐ฌ CODEC OPTIONS ๐ฌ
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. Everyone's got their own little settings, love that for them 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. Also some options are meant only for decoding or encoding. Read the label before you use it, bestie ๐
Options may be set by specifying -option value in the FFmpeg tools, or by setting the value explicitly in the "AVCodecContext" options or using the libavutil/opt.h API for programmatic use.
The list of supported options follow:
binteger (encoding,audio,video) โ Set bitrate in bits/s. Default value is200K.abinteger (encoding,audio) โ Set audio bitrate (in bits/s). Default value is128K.btinteger (encoding,video) โ 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. ๐ฌ So like, don't crank it down too hard.flagsflags (decoding/encoding,audio,video,subtitles) โ Set generic flags.
Possible values:
mv4โ Use four motion vector by macroblock (mpeg4).qpelโ Use 1/4 pel motion compensation.
loopโ use loop filter ๐ซqscaleโ use fixed qscale, periodt.pass1โ use the internal 2pass ratecontrol in first pass mode ๐ฌpass2โ use the internal 2pass ratecontrol in second pass mode ๐ฌgrayโ only decode/encode grayscale ๐ค๐คpsnrโ seterror[?]variables during encoding.truncatedโ input bitstream might be randomly truncated ๐drop_changedโ don't output frames whose parameters differ from the first decoded frame in the stream. ErrorAVERROR_INPUT_CHANGEDis returned when a frame is dropped. so real ๐ildctโ use interlaced DCT.low_delayโ force low delay โกglobal_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. it's giving reproducibility icon ๐งชaicโ apply H263 advanced intra coding / mpeg4 ac prediction.ilmeโ apply interlaced motion estimation.cgopโ use closed gop ๐ชoutput_corruptโ output even potentially corrupted frames. lowkey chaotic but okay ๐ซ
time_baserational number โ 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 be 1 / frame_rate and timestamp increments should be identically 1. the way this is literally the backbone of timestamp math ๐ฆ
ginteger (encoding,video) โ set the group of picture (GOP) size. Default value is12.arinteger (decoding/encoding,audio) โ set audio sampling rate (in Hz) ๐งacinteger (decoding/encoding,audio) โ set number of audio channels.cutoffinteger (encoding,audio) โ set cutoff bandwidth. (Supported only by selected encoders, see their respective documentation sections.) iykyk, check your encoder's docs ๐frame_sizeinteger (encoding,audio) โ set audio frame size.
Each submitted frame except the last must contain exactly frame_size samples per channel. May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, in that case the frame size is not restricted. It is set by some decoders to indicate constant frame size. โจ
frame_numberinteger โ set the frame number.delayinteger โ (that's it, that's the option ๐ )qcompfloat (encoding,video) โ 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.qblurfloat (encoding,video) โ set video quantizer scale blur (VBR).qmininteger (encoding,video) โ set min video quantizer scale (VBR). Must be included between-1and69, default value is2.qmaxinteger (encoding,video) โ set max video quantizer scale (VBR). Must be included between-1and1024, default value is31.qdiffinteger (encoding,video) โ set max difference between the quantizer scale (VBR).bfinteger (encoding,video) โ set max number of B frames between non-B-frames.
Must be an integer between -1 and 16. 0 means that B-frames are disabled. If a value of -1 is used, it will choose an automatic value depending on the encoder. Default value is 0.
b_qfactorfloat (encoding,video) โ set qp factor between P and B frames.codec_taginteger โ (just vibes and a tag ๐ท๏ธ)bugflags (decoding,video) โ workaround for not auto-detected encoder bugs ๐
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 ๐truncโ trancated frames
strictinteger (decoding/encoding,audio,video) โ 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. โ ๏ธ bestie pls heed this one
b_qoffsetfloat (encoding,video) โ set QP offset between P and B frames.err_detectflags (decoding,audio,video) โ set error detection flags ๐
Possible values:
crccheckโ verify embedded CRCsbitstreamโ detect bitstream specification deviationsbufferโ detect improper bitstream lengthexplodeโ abort decoding on minor error detection ๐ฅignore_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. ๐ญ fr fr it's for analysis not aestheticscarefulโ 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_framesinteger โ (yep, that's the whole thing ๐ซถ)block_aligninteger โ (no extra deets, it is what it is)rc_override_countinteger โ (just a count, bestie)maxrateinteger (encoding,audio,video) โ set max bitrate tolerance (in bits/s). Requiresbufsizeto be set. don't forget the bufsize or it won't slay ๐ฅminrateinteger (encoding,audio,video) โ set min bitrate tolerance (in bits/s). Most useful in setting up a CBR encode. It is of little use elsewise.bufsizeinteger (encoding,audio,video) โ set ratecontrol buffer size (in bits).i_qfactorfloat (encoding,video) โ set QP factor between P and I frames.i_qoffsetfloat (encoding,video) โ set QP offset between P and I frames.dctinteger (encoding,video) โ set DCT algorithm.
Possible values:
autoโ autoselect a good one (default)fastintโ fast integerintโ accurate integermmxaltivecfaanโ floating point AAN DCT
lumi_maskfloat (encoding,video) โ compress bright areas stronger than medium ones โจtcplx_maskfloat (encoding,video) โ set temporal complexity masking.scplx_maskfloat (encoding,video) โ set spatial complexity masking.p_maskfloat (encoding,video) โ set inter masking.dark_maskfloat (encoding,video) โ compress dark areas stronger than medium ones ๐คidctinteger (decoding/encoding,video) โ select IDCT implementation.
Possible values:
autointsimplesimplemmxsimpleautoโ automatically pick an IDCT compatible with the simple onearmaltivecsh4simplearmsimplearmv5tesimplearmv6simpleneonxvidfaaniโ floating point AAN IDCT
slice_countinteger โ (that's all, just a count ๐)ecflags (decoding,video) โ set error concealment strategy ๐ฉน
Possible values:
guess_mvsโ iterative motion vector (MV) search (slow) ๐ขdeblockโ use strong deblock filter for damaged MBsfavor_interโ favor predicting from the previous frame instead of the current
bits_per_coded_sampleinteger โ (no description, it's literally just the number of bits per coded sample ๐ )aspectrational number (encoding,video) โ set sample aspect ratio.sarrational number (encoding,video) โ set sample aspect ratio. Alias toaspect. same thing, different name bestie ๐debugflags (decoding/encoding,audio,video,subtitles) โ print specific debug info ๐
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
cmpinteger (encoding,video) โ 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, slow ๐ขzeroโ0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snow โ๏ธw97โ 9/7 wavelet, only used in snow โ๏ธdctmaxchroma
subcmpinteger (encoding,video) โ set sub 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, slow ๐ขzeroโ0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used in snow โ๏ธw97โ 9/7 wavelet, only used in snow โ๏ธdctmaxchroma
mbcmpinteger (encoding,video) โ set macroblock compare function.
Possible values:
sadโ sum of absolute differences, fast (this is the default btw ๐ )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 โ like, it's giving "why would you" energy)bitโ number of bits needed for the blockrdโ rate distortion optimal, slow ๐zeroโ literally just0vsadโ sum of absolute vertical differencesvsseโ sum of squared vertical differencesnsseโ noise preserving sum of squared differencesw53โ 5/3 wavelet, only used insnoww97โ 9/7 wavelet, only used insnowdctmaxchroma
ildctcmpinteger (encoding,video) โ sets the interlaced dct compare function โจ
The possible values are, and yes it's the exact same lil' family of compare functions:
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 insnoww97โ 9/7 wavelet, only used insnowdctmaxchroma
dia_sizeinteger (encoding,video) โ sets the diamond type & size for motion estimation ๐
The ranges go like this, bestie, so pay attention:
(1024, INT_MAX)โ full motion estimation (slowest ๐ญ)(768, 1024]โumhmotion estimation(512, 768]โhexmotion estimation(256, 512]โl2sdiamond motion estimation[2,256]โvardiamond motion estimation(-1, 2)โ small diamond motion estimation-1โ funny diamond motion estimation ๐น(INT_MIN, -1)โsabdiamond motion estimation
last_predinteger (encoding,video) โ sets the amount of motion predictors from the previous frame ๐ซถprecmpinteger (encoding,video) โ sets the pre motion estimation compare function โจ
The possible values (yep, the same iconic lineup):
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 insnoww97โ 9/7 wavelet, only used insnowdctmaxchroma
pre_dia_sizeinteger (encoding,video) โ sets the diamond type & size for the motion estimation pre-pass ๐subqinteger (encoding,video) โ sets the sub pel motion estimation quality โญme_rangeinteger (encoding,video) โ sets the limit of motion vectors range (1023for DivX player, iykyk)global_qualityinteger (encoding,audio,video)slice_flagsintegermbdinteger (encoding,video) โ sets the macroblock decision algorithm (high quality mode) ๐
Possible values:
simpleโ usembcmp(default)bitsโ use fewest bitsrdโ use best rate distortion
rc_init_occupancyinteger (encoding,video) โ sets the number of bits which should be loaded into the rc buffer before decoding even starts ๐ซถflags2flags (decoding/encoding,audio,video,subtitles)
Possible values, bestie:
fastโ allow non spec compliant speedup tricks ๐๏ธnooutโ skip bitstream encodingignorecropโ ignore cropping information fromspslocal_headerโ place global headers at every keyframe instead of inextradatachunksโ frame data might be split into multiple chunksshowallโ show all frames before the first keyframeexport_mvsโ export motion vectors into frame side-data (see"AV_FRAME_DATA_MOTION_VECTORS") for codecs that support it. Also peepdoc/examples/export_mvs.c๐skip_manualโ do not skip samples and export skip information as frame side dataass_ro_flush_noopโ do not reset the ASSReadOrderfield on flushicc_profilesโ generate/parse embedded ICC profiles from/to colorimetry tags ๐
export_side_dataflags (decoding/encoding,audio,video,subtitles)
Possible values:
mvsโ export motion vectors into frame side-data (see"AV_FRAME_DATA_MOTION_VECTORS") for codecs that support it. Also seedoc/examples/export_mvs.cprftโ export encoder Producer Reference Time into packet side-data (see"AV_PKT_DATA_PRFT") for codecs that support itvenc_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 VP9film_grainโ export film grain parameters through frame side data (see"AV_FRAME_DATA_FILM_GRAIN_PARAMS"). Supported at present by AV1 decoders ๐๏ธenhancementsโ 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 to be used, in case the selected codec implementation supports multi-threading ๐งต
Possible values:
auto,0โ automatically select the number of threads to set
Default value is auto. Slay.
dcinteger (encoding,video) โ setsintra_dc_precisionnssewinteger (encoding,video) โ sets thensseweight โ๏ธskip_topinteger (decoding,video) โ sets the number of macroblock rows at the top which are skipped โฌ๏ธskip_bottominteger (decoding,video) โ sets the number of macroblock rows at the bottom which are skipped โฌ๏ธprofileinteger (encoding,audio,video) โ sets the encoder codec profile. Default value isunknown. Encoder specific profiles are documented in the relevant encoder documentation ๐levelinteger (encoding,audio,video) โ sets the encoder level. This level depends on the specific codec, and might correspond to the profile level. It is set by default tounknown.
Possible values:
unknown
lowresinteger (decoding,audio,video) โ decode at1= 1/2,2= 1/4,3= 1/8 resolutions ๐mblmininteger (encoding,video) โ sets the min macroblock lagrange factor (VBR)mblmaxinteger (encoding,video) โ sets the max macroblock lagrange factor (VBR)
skip_loop_filterinteger (decoding,video)skip_idctinteger (decoding,video)skip_frameinteger (decoding,video)
Okay so these three besties make the decoder discard processing depending on the frame type selected by the option value ๐ซถ
skip_loop_filter skips frame loop filtering, skip_idct skips frame IDCT/dequantization, and skip_frame skips decoding.
Possible values:
noneโ discard no framedefaultโ discard useless frames like 0-sized framesnorefโ discard all non-reference framesbidirโ discard all bidirectional framesnokeyโ discard all frames excepts keyframesnointraโ discard all frames except I framesallโ discard all frames ๐
Default value is default.
bidir_refineinteger (encoding,video) โ refine the two motion vectors used in bidirectional macroblocks โจkeyint_mininteger (encoding,video) โ sets the minimum interval between IDR-framesrefsinteger (encoding,video) โ sets reference frames to consider for motion compensationtrellisinteger (encoding,audio,video) โ sets rate-distortion optimal quantizationmv0_thresholdinteger (encoding,video)compression_levelinteger (encoding,audio,video)bits_per_raw_sampleintegerchannel_layoutinteger (decoding/encoding,audio) โ see the Channel Layout section in the ffmpeg-utils(1) manual for the required syntax ๐rc_max_vbv_usefloat (encoding,video)rc_min_vbv_usefloat (encoding,video)
color_primariesinteger (decoding/encoding,video) ๐จ
Possible values:
bt709โ BT.709bt470mโ BT.470 Mbt470bgโ BT.470 BGsmpte170mโ SMPTE 170 Msmpte240mโ SMPTE 240 Mfilmโ Filmbt2020โ BT.2020smpte428smpte428_1โ SMPTE ST 428-1smpte431โ SMPTE 431-2smpte432โ SMPTE 432-1jedec-p22โ JEDEC P22
color_trcinteger (decoding/encoding,video) ๐
Possible values:
bt709โ BT.709gamma22โ BT.470 Mgamma28โ BT.470 BGsmpte170mโ SMPTE 170 Msmpte240mโ SMPTE 240 Mlinearโ Linearloglog100โ Loglog_sqrtlog316โ Log square rootiec61966_2_4iec61966-2-4โ IEC 61966-2-4bt1361bt1361eโ BT.1361iec61966_2_1iec61966-2-1โ IEC 61966-2-1bt2020_10bt2020_10bitโ BT.2020 - 10 bitbt2020_12bt2020_12bitโ BT.2020 - 12 bitsmpte2084โ SMPTE ST 2084smpte428smpte428_1โ SMPTE ST 428-1arib-std-b67โ ARIB STD-B67
colorspaceinteger (decoding/encoding,video) ๐
Possible values:
rgbโ RGBbt709โ BT.709fccโ FCCbt470bgโ BT.470 BGsmpte170mโ SMPTE 170 Msmpte240mโ SMPTE 240 Mycocgโ YCOCGbt2020ncbt2020_nclโ BT.2020 NCLbt2020cbt2020_clโ BT.2020 CLsmpte2085โ SMPTE 2085chroma-derived-ncโ Chroma-derived NCLchroma-derived-cโ Chroma-derived CLictcpโ ICtCpcolor_rangeinteger (decoding/encoding,video) โ bestie, if you're using this as an input parameter it's literally just a lil hint to the decoder telling it whichcolor_rangethe input has. The possible values, slay:tvmpeglimitedโ MPEG (219*2^(n-8))pcjpegfullโ JPEG (2^n-1)
chroma_sample_locationinteger (decoding/encoding,video) โ where the chroma samples sit, no cap. The possible values:leftcentertoplefttopbottomleftbottom
alpha_modeinteger (decoding/encoding,video) โ the transparency vibe. Possible values:premultipliedstraight
log_level_offsetinteger โ sets the log level offset. That's it, that's the whole gig โจslicesinteger (encoding,video) โ the number of slices, used in parallelized encoding. More slices = more parallelism, iykyk ๐งthread_typeflags (decoding/encoding,video) โ picks which multithreading methods to use. Heads up though: usingframewill increase the decoding delay by one frame per thread, so clients that can't provide future frames should not use it ๐
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, fr fr.frameโ decode more than one frame at once.
Default value is slice+frame. Periodt ๐
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 that's the whole description, bestie, it's giving mysterious main character energy ๐sub_charencencoding (decoding,subtitles) โ sets the input subtitles character encoding.field_orderfield_order (video) โ sets/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). It works just like thegrayflag in theflagsoption, except it skips chroma information instead of alpha. Default is0.codec_whitelistlist (input) โ a","-separated list of allowed decoders. By default all are allowed ๐dump_separatorstring (input) โ the 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_pixelsinteger (decoding/encoding,video) โ maximum number of pixels per image. Use this to avoid out-of-memory failures from huge images. Protect your RAM, queen ๐apply_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 isn't met, the cropping will be partially applied to maintain alignment. Default is1(enabled).
Note, bestie: 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. ๐
๐ฌ DECODERS ๐ฌ
Decoders are these configured elements in FFmpeg that let you decode multimedia streams. Iconic behaviour, honestly.
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 every available decoder with the configure option --list-decoders ๐ฆ
You can also disable all the decoders with the configure option --disable-decoders and then selectively enable / disable single decoders with --enable-decoder=DECODER / --disable-decoder=DECODER.
And the -decoders option of the ff* tools will display the list of enabled decoders. Slay ๐ธ
๐น VIDEO DECODERS ๐น
A description of some of the currently available video decoders follows. Buckle up.
av1 โจ
AOMedia Video 1 (AV1) decoder.
Options
operating_pointโ selects an operating point of a scalable AV1 bitstream (0-31). Default is0.
hevc ๐
HEVC (AKA ITU-T H.265 or ISO/IEC 23008-2) decoder.
The decoder supports MV-HEVC multiview streams with at most two views. Which views get output is selected by supplying a list of view IDs to the decoder (the view_ids option). You can set this option either statically before decoder init, or from the get_format() callback โ which is super useful for when the view count or IDs change dynamically during decoding.
Only the base layer is decoded by default.
Note: if you're using the ffmpeg CLI tool, you should be using view specifiers as documented in its manual, rather than the options documented here. Okay? Okay ๐
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. All of them. The whole squad ๐ซถview_ids_available(MV-HEVC) โ the caller may read this option 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 then the value is informational only and may be incorrect (e.g. when the stream contains multiple distinct VPS NALUs). So likeโฆ read it at your own risk, bestie ๐ญ
view_pos_available(MV-HEVC) โ the caller may read this option 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 the view with IDview_ids_available[i].
Same validity restrictions as for view_ids_available apply to this option. Same rules, different option, no cap.
rawvideo ๐ฅ
Raw video decoder.
This decoder decodes rawvideo streams.
Options
top,top_field_firstโ 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
libdav1d ๐ง
dav1d AV1 decoder.
libdav1d allows libavcodec to decode the AOMedia Video 1 (AV1) codec. It 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 sets the max amount of frames the decoder may buffer internally. The default value is0(autodetect).filmgrainโ applies film grain to the decoded video if present in the bitstream. Defaults to the internal default of the library.
โ ๏ธ 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. Don't say I didn't warn you ๐
oppointโ selects an operating point of a scalable AV1 bitstream (0-31). Defaults to the internal default of the library.alllayersโ outputs all spatial layers of a scalable AV1 bitstream. The default value isfalse.
libdavs2 ๐
AVS2-P2/IEEE1857.4 video decoder wrapper.
This decoder allows libavcodec to decode AVS2 streams with the davs2 library. Short and sweet, we love that for her.
libuavs3d โญ
AVS3-P2/IEEE1857.10 video decoder.
libuavs3d allows libavcodec to decode AVS3 streams. It 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 sets the amount of frame threads to use during decoding. The default value is0(autodetect).
libxevd ๐
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, bestie ๐
To get more accurate and extensive documentation of the libxevd options, invoke the command xevd_app --help or consult the libxevd documentation.
threads(threads) โ force the use of a specific number of threads.
QSV Decoders ๐
The family of Intel QuickSync Video decoders (VC1, MPEG-2, H.264, HEVC, JPEG/MJPEG, VP8, VP9, AV1, VVC). A whole dynasty, honestly.
Common Options
The following options are supported by all qsv decoders:
async_depthโ internal parallelization depth. The higher the value, the higher the latency. Choose wisely ๐ซgpu_copyโ a GPU-accelerated copy between video and system memory. The values:defaultonoff
HEVC Options
Extra options for hevc_qsv:
load_pluginโ a user plugin to load in an internal session:nonehevc_swhevc_hw
load_pluginsโ a:-separate list of hexadecimal plugin UIDs to load in an internal session.
v210 ๐
Uncompressed 4:2:2 10-bit decoder. Simple. Effective. Iconic.
Options
custom_strideโ sets 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. Special little guy, that one ๐
๐ง AUDIO DECODERS ๐ง
okay bestie so this is the part where we meet the decoders that turn your squiggly audio bytes into actual sound ๐ here's the rundown on some of the ones chillin' in the codebase right now.
๐ ac3
the AC-3 audio decoder, periodt.
this one implements part of ATSC A/52:2010 and ETSI TS 102 366, plus the undocumented RealAudio 3 (a.k.a. dnet). yes, the undocumented one โ she read the forbidden texts, no cap ๐ญ
โจ AC-3 Decoder Options โจ
-drc_scalevalue โ the Dynamic Range Scale Factor, aka the factor applied to dynamic range values from the AC-3 stream. it's applied exponentially, fyi. default value is1. there are 3 notable scale factor ranges and they're giving very different vibes:drc_scale == 0โ DRC disabled. produces full range audio ๐ฅ0 < drc_scale <= 1โ DRC enabled. applies a fraction of the stream DRC value. audio reproduction lands somewhere between full range and full compression, iykyk.drc_scale > 1โ DRC enabled. appliesdrc_scaleasymmetrically. loud sounds are fully compressed, soft sounds get enhanced โจ
๐ธ flac
the FLAC audio decoder ๐ฆ
this decoder aims to implement the complete FLAC specification from Xiph. ambitious queen, we love to see it ๐
๐ FLAC Decoder options ๐
-use_buggy_lpcโ so the lavc FLAC encoder used to produce buggy streams with high lpc values (like the default value, lol ๐). this option makes it possible to decode such streams correctly by using lavc's old buggy lpc logic for decoding. yes bestie, we're using the bug on purpose to fix the bug. iconic.
๐ง ffwavesynth
internal wave synthesizer ๐
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 ๐ so likeโฆ don't ask, she's mysterious.
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 ๐ versatile.
๐ฆ 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.
โญ Options โญ
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). so like, off by default, you gotta opt in ๐ซถ
๐ libmpeghdec
libmpeghdec decoder wrapper.
libmpeghdec allows libmpeghdec to decode the MPEG-H 3D audio codec ๐งโจ requires the presence of the libmpeghdec headers and library during configuration. you need to explicitly configure the build with --enable-libmpeghdec --enable-nonfree.
heads up babes: that --enable-nonfree is right there in the configure line โ it's what the build needs, fr fr.
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 ๐ซถ good to know, right?
๐ 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 โจ same energy, wideband edition.
๐ 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 and that's on having options.
โจ SUBTITLES DECODERS โจ
Okay bestie, this is the subtitle decoder zone โ where the little words at the bottom of your screen get their whole personality. Let's go ๐
๐ libaribb24
A decoder for ARIB STD-B24 captions. Yes, it's a whole standard, and yes it's iconic.
It implements profiles A and C of the ARIB STD-B24 standard. Slay.
๐ libaribb24 Decoder Options
-aribb24-base-pathpath โ Sets the base path for the libaribb24 library. This is what it uses for reading config files (for custom unicode conversions) and for dumping non-text symbols as images under that location. Unset by default โ no cap, it just vibes with no path until you give it one ๐ซถ-aribb24-skip-ruby-textboolean โ Tells the decoder wrapper to skip text blocks that contain half-height ruby text. Enabled by default โจ
๐ฆ libaribcaption
Yet another ARIB STD-B24 caption decoder, but this one uses the external libaribcaption library. More decoders, more fun, periodt.
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. Trilingual legend behavior 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". And listen โ if both libaribb24 and libaribcaption are enabled, the libaribcaption decoder precedes. It's giving main character energy ๐
๐ธ libaribcaption Decoder Options
-sub_typesubtitle_type โ Specifies the format of the decoded subtitles. The options 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. iykyk ๐
-caption_encodingencoding_scheme โ Specifies the encoding scheme of input subtitle text. Your choices: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 the 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.
-fontfont_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. ๐-ass_single_rectboolean โ 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 singleAVSubtitle, 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 is false.
If your player cannot handle AVSubtitles with multiple ASS rectangles properly, set this option to true or define ASS_SINGLE_RECT=1 to change default behavior at compilation. ๐ซถ
-force_outline_textboolean โ Specify whether to always render outline text for all characters regardless of the indication by character style. The default isfalse.-outline_widthnumber (0.0 - 3.0) โ Specify width for outline text, in dots (relative). The default is1.5.-ignore_backgroundboolean โ Specify whether to ignore background color rendering. The default isfalse.-ignore_rubyboolean โ Specify whether to ignore rendering for ruby-like (furigana) characters. The default isfalse.-replace_drcsboolean โ Specify whether to render replaced DRCS characters as Unicode characters. The default istrue.-replace_msz_asciiboolean โ Specify whether to replace MSZ (Middle Size; half width) fullwidth alphanumerics with halfwidth alphanumerics. The default istrue.-replace_msz_japaneseboolean โ Specify whether to replace some MSZ (Middle Size; half width) fullwidth Japanese special characters with halfwidth ones. The default istrue.-replace_msz_glyphboolean โ Specify whether to replace MSZ (Middle Size; half width) characters with halfwidth glyphs if the fonts support 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. ๐-canvas_sizeimage_size โ Specify the resolution of the canvas to render subtitles to; usually, this should be the frame size of the 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 the "-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 the "-canvas_size" option is not specified. If the "-canvas_size" option is specified with different size, the caption will be stretched or shrunk as specified size with calculated SAR. โจ
โญ libaribcaption decoder usage examples
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
๐ dvbsub
Options
compute_clutโ the math-y glow-up option:-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 the default. ๐
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. Retro but make it fashion ๐
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-bit 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". So many hex codes, so little time ๐ญ
ifo_paletteโ Specify the IFO file from which the global palette is obtained. (experimental) โ it's giving work in progress, handle with care ๐งforced_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๏ธ 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". ๐ฅ
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. Ngl, vintage transmission problems are a mood ๐txt_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. Cleaning up the mess, love that for us ๐txt_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. Live forever or until the next thing happens, honestly same ๐txt_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.
๐ฅ BITSTREAM FILTERS ๐ฅ
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". Look at all those filters, obsessed ๐
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, it's your build, your rules 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 '='. Periodt โจ
ffmpeg -i INPUT -c:v copy -bsf:v filter1[=opt1=str1:opt2=str2][,filter2] OUTPUT
Okay so below is the โจ current โจ roster of bitstream filters, with all their lil parameters (if they have any). Buckle up bestie, some of these have a lot of options ๐
๐ aac_adtstoasc
Converts an MPEG-2/4 AAC ADTS stream into an MPEG-4 Audio Specific Configuration bitstream. Glow-up, but for headers.
What it actually does: builds an MPEG-4 AudioSpecificConfig out of an MPEG-2/4 ADTS header, then yeets the ADTS header entirely. Bye ๐
And it's required in some situations โ for example when you're copying an AAC stream from a raw ADTS AAC container or an MPEG-TS container over to MP4A-LATM, to an FLV file, or to MOV/MP4 files and related formats like 3GP or M4A. Good news tho: for MP4A-LATM and MOV/MP4 and friends it gets auto-inserted, so you don't even have to think about it ๐ซถ
๐ฆ av1_metadata
Modify metadata embedded in an AV1 stream. Little header surgery, no cap.
tdโ Insert or remove temporal delimiter OBUs in all temporal units of the stream.insertโ Insert a TD at the beginning of every TU which does not already have one.removeโ Remove the TD from the beginning of every TU which has one.
color_primaries,transfer_characteristics,matrix_coefficientsโ Set the color description fields in the stream (see AV1 section 6.4.2).color_rangeโ Set the color range in the stream (see AV1 section 6.4.2; note that this cannot 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.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_rateis not also set. ๐delete_paddingโ Deletes Padding OBUs.
๐ธ chomp
Removes zero padding at the end of a packet. Justโฆ monch. ๐
๐ dca_core
Extracts the core from a DCA/DTS stream, dropping extensions such as DTS-HD. It's giving "keep the main character, lose the entourage".
๐ dovi_rpu
Manipulate Dolby Vision metadata in a HEVC/AV1 bitstream, optionally enabling metadata compression. Fancy fancy.
stripโ If enabled, strip 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.
๐ง dump_extra
Adds extradata to the beginning of the filtered packets โ except when those packets already exactly begin with the extradata that's intended to be added. We're not double-dipping, bestie.
freqโ The additional argument specifies which packets should be filtered. It accepts the values:k,keyframeโ add extradata to all key packetse,allโ add extradata to all packets
If not specified it is assumed k.
For example, the following ffmpeg command forces a global header (thus disabling individual packet headers) in the H.264 packets generated by the libx264 encoder, but 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
โญ dv_error_marker
Blocks in DV which are marked as damaged get replaced by blocks of the specified color. It's giving "we fixed it in post" โจ
colorโ The color to replace damaged blocks bystaโ A 16 bit mask which specifies 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 concealmenterrโ Error, No concealmentresโ Reservednotokโ Error or concealmentnotresโ Not reservedAa,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
๐ eac3_core
Extracts the core from an E-AC-3 stream, dropping extra channels. Same energy as dca_core but for E-AC-3, iykyk.
๐ซถ eia608_to_smpte436m
Convert from a EIA_608 stream to a SMPTE_436M_ANC data stream, wrapping the closed captions in CTA-708 CDP VANC packets. Very niche, very slay.
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 samples8bit_color_diffโ 8-bit component color difference samples8bit_luma_and_color_diffโ 8-bit component luma and color difference samples10bit_lumaโ 10-bit component luma samples10bit_color_diffโ 10-bit component color difference samples10bit_luma_and_color_diffโ 10-bit component luma and color difference samples8bit_luma_parity_errorโ 8-bit component luma samples with parity error8bit_color_diff_parity_errorโ 8-bit component color difference samples with parity error8bit_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 integercdp_hdr_sequence_cntrandcdp_ftr_sequence_cntrfields. Defaults to0.cdp_frame_rateโ Set the CDP'scdp_frame_ratefield. 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.
๐ฅ extract_extradata
Extract the in-band extradata. Okay so context first, because this one's actually kinda interesting:
Certain codecs allow the long-term headers (e.g. MPEG-2 sequence headers, or H.264/HEVC (VPS/)SPS/PPS) to be transmitted either "in-band" (i.e. as a part of the bitstream containing the coded frames) or "out of band" (e.g. on the container level). That latter form is called "extradata" in FFmpeg terminology. The more you know ๐ซ
This bitstream filter detects the in-band headers and makes them available as extradata.
removeโ When this option is enabled, the long-term headers are removed from the bitstream after extraction.
๐ filter_units
Remove units with types in โ or not in โ a given set from the stream. Bouncer energy: some units get in, some don't.
pass_typesโ List of unit types or ranges of unit types to pass through while removing all others. This is specified 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 removed and all others 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.
โ ๏ธ Extradata is unchanged by this transformation, but heads up: if the stream contains inline parameter sets then the output may be unusable if they are removed. Consider yourself warned bestie ๐ญ
For example, 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
Extract the Rgb or Alpha part of an HAPQA file, without recompression, in order to create an HAPQ or an HAPAlphaOnly file. No quality loss, no drama 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
Modify metadata embedded in an H.264 stream. Yes, another one. Yes, it's also iconic.
๐ Heads up: this list continues past what you see here โ more options are coming right up in the next chunk. Don't panic, we're not skipping anything ๐ซถ
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).fixed_frame_rate_flagโ Set whether the stream has fixed framerate โ typically this indicates that the framerate is exactly half the tick rate, but the exact meaning is dependent on interlacing and the picture structure (see H.264 section E.2.1 and table E-6).
zero_new_constraint_set_flags ๐
okay so this one zeroes out constraint_set4_flag and constraint_set5_flag inside the SPS. bestie, those bits were reserved in an older version of the H.264 spec, which means some hardware decoders straight up require them to be zero ๐. the slay part? zeroing them still leaves you with a perfectly valid bitstream, so no cap, nothing breaks. โจ
crop_left, crop_right, crop_top, crop_bottom ๐ฆ
these four set the frame cropping offsets in the SPS. if the stream is already cropped, these values will replace the current ones โ like a glow-up for your crop box ๐ .
heads up though: these fields are set in pixels, and some sizes may just not be representable if the chroma is subsampled or the stream is interlaced (see H.264 section 7.4.2.1.1). so like, do a vibe check on your numbers first ๐.
sei_user_data โญ
this one inserts a string as SEI unregistered user data. the argument has to be of the form UUID+string, where the UUID is hex digits possibly separated by hyphens, and the string can literally be anything you want ๐ซถ.
for example, 086f3693-b7b3-4f2c-9653-21492feee5b8+hello will insert the string hello associated with the given UUID. iconic.
delete_filler ๐
deletes both filler NAL units and filler SEI messages. that's it. that's the whole thing. bye filler ๐
display_orientation ๐ธ
insert, extract or remove Display orientation SEI messages. see H.264 section D.1.27 and D.2.27 for the syntax and semantics (iykyk).
the modes are:
passinsertremoveextract
default is pass.
insert mode works in conjunction with the rotate and flip options, which is lowkey cute. any pre-existing Display orientation messages will be removed in insert or remove mode. and extract mode? it attaches the display matrix to the packet as side data โจ.
rotate ๐
set rotation in display orientation SEI (anticlockwise angle in degrees, bestie โ anticlockwise, don't forget). range is -360 to +360. default is NaN.
flip ๐ช
set flip in display orientation SEI. your options:
horizontalvertical
default is unset.
level ๐
set the level in the SPS. refer to H.264 section A.3 and tables A-1 to A-5, fr fr.
the argument must be one of these three flavors:
- the name of a level (for example,
4.2) - a
level_idcvalue (for example,42) - the special name
auto, which tells the filter to attempt to guess the level from the input stream properties ๐ฅ
h264_mp4toannexb ๐ง
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 โ typically the MPEG-2 transport stream format (muxer mpegts). so if your thing refuses to play, this might be why 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. so like, you don't even have to ask ๐
h264_redundant_pps ๐
this applies a specific fixup to some Blu-ray BDMV H264 streams which contain redundant PPSs. those PPSs modify irrelevant parameters of the stream, confusing other transformations which require the correct extradata (rude, honestly).
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 ๐ญ. one side effect, for example, is seeking will return garbled output until a new PPS appears. literally the worst.
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. queen behavior ๐โจ
hevc_metadata ๐
modify metadata embedded in an HEVC stream. let's go through the options one by one, bestie:
aud
insert or remove AUD NAL units in all access units of the stream. pick your fighter:
insertremove
sample_aspect_ratio
set the sample aspect ratio in the stream in the VUI parameters.
video_format, video_full_range_flag
set the video format in the stream (see H.265 section E.3.1 and table E.2).
colour_primaries, transfer_characteristics, matrix_coefficients
set the colour description in the stream (see H.265 section E.3.1 and tables E.3, E.4 and E.5). three tasty little options, one colour glow-up ๐
chroma_sample_loc_type
set the chroma sample location in the stream (see H.265 section E.3.1 and figure E.1).
tick_rate
set the tick rate in the VPS and VUI parameters (time_scale / num_units_in_tick). combined with num_ticks_poc_diff_one, this can set a constant framerate in the stream ๐.
ngl, note that it is likely to be overridden by container parameters when the stream is in a container. so don't get too attached, bestie.
num_ticks_poc_diff_one
set poc_proportional_to_timing_flag in VPS and VUI and use this value to set num_ticks_poc_diff_one_minus1 (see H.265 sections 7.4.3.1 and E.3.1). ignored if tick_rate is not also set โ so it's a package deal, no solo acts ๐.
crop_left, crop_right, crop_top, crop_bottom
set the conformance window cropping offsets in the SPS. these values will replace the current ones if the stream is already cropped โจ.
these fields are set in pixels. note that some sizes may not be representable if the chroma is subsampled (H.265 section 7.4.3.2.1). math is math, unfortunately ๐
width, height
set width and height after crop.
level
set the level in the VPS and SPS. see H.265 section A.4 and tables A.6 and A.7.
the argument must be:
- the name of a level (for example,
5.1) - a
general_level_idcvalue (for example,153for level 5.1) - the special name
auto, indicating that the filter should attempt to guess the level from the input stream properties โญ
hevc_mp4toannexb ๐ฆ
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) โ same energy as the H.264 one, different codec 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. auto-magic, no cap โจ
imxdump ๐ฌ
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. so like, check your version first, bestie ๐
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 ๐
convert MJPEG/AVI1 packets to full JPEG/JFIF packets.
so here's the lore: 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 ๐ญ, 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."
so 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. it's giving magical little JPEG makeover ๐งโจ
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 ๐
add an MJPEG A header to the bitstream, to enable decoding by Quicktime. short, sweet, slays.
mov2textsub ๐
extract a representable text file from MOV subtitles, stripping the metadata header from each subtitle packet.
see also the text2movsub filter โ they're like a matching set, bestie ๐ซถ
mpeg2_metadata ๐ธ
modify metadata embedded in an MPEG-2 stream. options time:
display_aspect_ratio
set the display aspect ratio in the stream.
the following fixed values are supported:
4/316/9221/100
any other value will result in square pixels being signalled instead (see H.262 section 6.3.3 and table 6-3). so like, choose wisely ๐ญ
frame_rate
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 section 6.3.3 and table 6-4). close enough is literally the whole vibe here ๐
video_format
set the video format in the stream (see H.262 section 6.3.6 and table 6-6).
colour_primaries, transfer_characteristics, matrix_coefficients
set the colour description in the stream (see H.262 section 6.3.6 and tables 6-7, 6-8 and 6-9). slay, colour trio ๐
mpeg4_unpack_bframes ๐ฅ
unpack DivX-style packed B-frames.
okay so DivX-style packed B-frames are not valid MPEG-4 โ they were only a workaround for the broken Video for Windows subsystem ๐. 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. not them being a whole mess 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 ๐
damages the contents of packets or simply drops them without damaging the container. can be used for fuzzing or testing error resilience/concealment โ like a lil chaos agent, but make it scientific ๐งชโจ
parameters:
amount
accepts an expression whose evaluation per-packet determines how often bytes in that packet will be modified. a value below 0 will result in a variable frequency. default is 0, which results in no modification. however, if neither amount nor drop is specified, amount will be set to -1. see below for accepted variables ๐
๐
drop
okay so this one takes an expression that gets evaluated per-packet, and whatever it spits out decides whether that packet gets yeeted. Positive value โ packet dropped, periodt. Negative value โ it's a variable chance of dropping, roughly inverse in proportion to how big the value is (bigger negative = less likely). Default is 0, which means nothing gets dropped. Peep the variable list below, bestie.
๐
dropamount
takes a non-negative integer, and gives you a variable chance of the packet getting dropped โ again, roughly inverse in proportion to the value. Default 0 = no drops, no drama. This one's kept around for backwards compatibility and it's literally equivalent to setting drop to a negative value of the same magnitude, i.e. "dropamount=4" is the same as "drop=-4". Also: it gets ignored if drop is also specified. so don't do both and expect magic, okay?
Both amount and drop accept expressions containing these variables:
nโ the index of the packet, starting from zero ๐tbโ the timebase for packet timestampsptsโ packet presentation timestampdtsโ packet decoding timestampnoptsโ constant representingAV_NOPTS_VALUEstartptsโ first non-AV_NOPTS_VALUEPTS seen in the streamstartdtsโ first non-AV_NOPTS_VALUEDTS seen in the streamduration,dโ packet duration, in timebase unitsposโ packet position in input; may be-1when unknown or not setsizeโ packet size, in byteskeyโ whether packet is marked as a keyframestateโ a pseudo random integer, primarily derived from the content of packet payload
โจ Examples
Apply modification to every byte but don't 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
This bitstream filter passes the packets through unchanged. literally does nothing. iconic behaviour honestly.
๐ pcm_rechunk
Repacketize PCM audio to a fixed number of samples per packet, or a fixed packet rate per second. Think of it as the asetnsamples audio filter's cousin โ except it works on audio packets instead of audio frames.
nb_out_samples,nโ sets 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 pads the last audio packet with silence so it contains the same number of samples as the previous ones (or roughly the same number โ seeframe_rate). Default value is1.frame_rate,rโ 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 isn't divisible by the frame rate, then the number of samples won't be constant โ it'll vary slightly so each packet starts as close to the frame boundary as possible. Using this option takes precedence overnb_out_samples.
You can generate that well known 1602-1601-1602-1601-1602 pattern of 48kHz audio for NTSC frame rate using the frame_rate option. slay:
ffmpeg -f lavfi -i sine=r=48000:d=1 -c pcm_s16le -bsf pcm_rechunk=r=30000/1001 -f framecrc -
๐ธ pgs_frame_merge
Merges 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"). so like, not optional, bestie.
๐ prores_metadata
Modifies color property metadata embedded in a prores stream. cute.
color_primariesโ sets 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 sets 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 sets 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
๐ remove_extra
Removes extradata from packets. It accepts the following parameter:
freqโ sets which frame types to remove extradata from:kโ remove extradata from non-keyframes onlykeyframeโ remove extradata from keyframes onlye,allโ remove extradata from all frames
โญ setts
Sets PTS and DTS in packets. It accepts the following parameters:
ts,pts,dtsโ set expressions for PTS, DTS or bothdurationโ set expression for durationtime_baseโ set output time baseprescaleโ set whether to convert time fields to user-set output time base before evaluation of expressions. Defaults to0.
The expressions get evaluated through the eval API and can contain the following constants:
Nโ the count of the input packet. Starting from0.TSโ the demux timestamp in input in case of"ts"or"dts"option, or presentation timestamp in case of"pts"optionPOSโ the original position in the file of the packet, or undefined if undefined for the current packetDTSโ the demux timestamp in inputPTSโ the presentation timestamp in inputDURATIONโ the duration in inputSTARTDTSโ the DTS of the first packetSTARTPTSโ the PTS of the first packetPREV_INDTSโ the previous input DTSPREV_INPTSโ the previous input PTSPREV_INDURATIONโ the previous input durationPREV_OUTDTSโ the previous output DTSPREV_OUTPTSโ the previous output PTSPREV_OUTDURATIONโ the previous output durationNEXT_DTSโ the next input DTSNEXT_PTSโ the next input PTSNEXT_DURATIONโ the next input durationTBโ the timebase in which time fields are denominated. The user-set output timebase ifprescaleis enabled, else the input timebase.TB_OUTโ the output timebaseSRโ the sample rate of stream packet belongsNOPTSโ theAV_NOPTS_VALUEconstant
For example, to set PTS equal to DTS (not recommended if B-frames are involved, just so you know ๐):
ffmpeg -i INPUT -c:a copy -bsf:a setts=pts=DTS out.mkv
๐ซถ showinfo
Logs basic packet information. Mainly useful for testing, debugging, and development. your bestie for "wait, what is this packet actually".
๐ง smpte436m_to_eia608
Converts from a "SMPTE_436M_ANC" data stream to a "EIA_608" stream โ extracting the closed captions from CTA-708 CDP VANC packets, and ignoring all other data. bye to everything else โจ
๐ text2movsub
Converts text subtitles to MOV subtitles (as used by the "mov_text" codec) with metadata headers. See also the mov2textsub filter โ the other direction, iykyk.
๐ฅ trace_headers
Logs 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 โ but depending on the build, only a subset of these may be available. check your build bestie.
๐ truehd_core
Extracts the core from a TrueHD stream, dropping ATMOS data. so long, atmos.
๐ vp9_metadata
Modifies metadata embedded in a VP9 stream.
color_spaceโ sets 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 profiles0and2. Available values:unknownbt601bt709smpte170smpte240bt2020rgb
color_rangeโ sets the color range value in the frame header. Note that any value imposed by the color space will take precedence over this value. Available values:tvpc
๐ฆ vp9_superframe
Merges 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. it's giving reparative surgery ๐
๐ vp9_superframe_split
Splits VP9 superframes into single frames. the reverse vibe.
๐ vp9_raw_reorder
Given a VP9 stream with correct timestamps but possibly out of order, inserts additional show-existing-frame packets to correct the ordering. it just wants things in the right order, honestly same.
๐ FORMAT OPTIONS ๐
Okay bestie, so the libavformat library is out here giving you a whole bunch of generic global options โ and the iconic part? You can set them on all the muxers and demuxers. Every single one. โจ And on top of that, each muxer or demuxer might have its own little private options that are specific to that one component, like a signature vibe.
You can 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. ๐ซถ
The list of supported options follows, and yes, we're doing all of them:
avioflagsflags (input/output) โ Possible values are giving:directโ reduce buffering. Lowkey less buffering, highkey less latency.
probesizeinteger (input) โ sets the probing size in bytes, i.e. the size of the data to analyze to get stream information. A higher value lets you detect more information in case it's dispersed into the stream, but it will increase latency โ trade-off city. Must be an integer not lesser than32. It's5000000by default. ๐max_probe_packetsinteger (input) โ sets the maximum number of buffered packets when probing a codec. Default is2500packets.packetsizeinteger (output) โ sets packet size. That's it, that's the whole option.fflagsflags โ sets format flags. Some are implemented for a limited number of formats, so don't come for me if your fave format doesn't do all of them.
Possible values for input files:
discardcorruptโ discard corrupted packets. Bye, trash. ๐fastseekโ enables fast, but inaccurate seeks for some formats. Speed over precision, we love a trade-off.genptsโ generate missing PTS if DTS is present.igndtsโ 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. Fr fr, remember that.ignidxโ ignore index.nobufferโ reduce the latency introduced by buffering during initial input streams analysis.nofillinโ do not fill in missing values in packet fields that can be exactly calculated.noparseโ disable AVParsers, this needs+nofillintoo. Not me needing a whole extra flag, but okay.sortdtsโ 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. She's the default for a reason. ๐bitexactโ 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.flush_packetsโ write out packets immediately.shortestโ stop muxing at the end of the shortest stream. It may be needed to increasemax_interleave_deltato avoid flushing the longer streams before EOF. Important detail, don't skip it.
seek2anyinteger (input) โ allow seeking to non-keyframes on demuxer level when supported if set to1. Default is0.analyzedurationinteger (input) โ specify how many microseconds are analyzed to probe the input. A higher value will enable detecting more accurate information, but will increase latency (again with the latency, I know). It defaults to5,000,000microseconds =5seconds.cryptokeyhexadecimal string (input) โ set decryption key. Secretive. Mysterious. Main character energy. ๐ต๏ธโ๏ธindexmeminteger (input) โ set max memory used for timestamp index (per stream).rtbufsizeinteger (input) โ set max memory used for buffering real-time frames.fdebugflags (input/output) โ print specific debug info. Possible values:ts
max_delayinteger (input/output) โ set maximum muxing or demuxing delay in microseconds.fpsprobesizeinteger (input) โ set number of frames used to probe fps.audio_preloadinteger (output) โ set microseconds by which audio packets should be interleaved earlier.chunk_durationinteger (output) โ set microseconds for each chunk.chunk_sizeinteger (output) โ set size in bytes for each chunk.err_detect,f_err_detectflags (input) โ set error detection flags. Heads up though:f_err_detectis deprecated and should be used only via the ffmpeg tool. Don't be out here using the deprecated one, bestie. ๐
Possible values:
crccheckโ verify embedded CRCs.bitstreamโ detect bitstream specification deviations.bufferโ detect improper bitstream length.explodeโ abort decoding on minor error detection. Dramatic, honestly iconic.carefulโ consider things that violate the spec and have not been seen in the wild as errors.compliantโ consider all spec non compliancies as errors.aggressiveโ consider things that a sane encoder should not do as an error.
max_interleave_deltainteger (output) โ set maximum buffering duration for interleaving. The duration is expressed in microseconds, and defaults to10000000(10 seconds). Ngl, that's the whole point so let me explain it properly:
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.
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_timestampsinteger (input) โ use wallclock as timestamps if set to1. Default is0.avoid_negative_tsinteger (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.make_zeroโ shift timestamps so that the first timestamp is0.auto(default) โ enables shifting when required by the target format.disabledโ 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. So like, everything moves together, no chaos. ๐
skip_initial_bytesinteger (input) โ set number of bytes to skip before reading header and frames if set to1. Default is0.correct_ts_overflowinteger (input) โ correct single timestamp overflows if set to1. Default is1.flush_packetsinteger (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. Three whole moods. โจoutput_ts_offsetoffset (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.
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).
format_whitelistlist (input) โ,separated list of allowed demuxers. By default all are allowed. A little VIP list for your demuxers. ๐๏ธdump_separatorstring (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_streamsinteger (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.skip_estimate_duration_from_ptsbool (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_probesizeinteger (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 is 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. ๐ฎโ๐จ Okay that was a lot but every word of it matters.strict,f_strictinteger (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 software.strictโ strictly conform to all the things in the spec no matter what consequences. No notes.normalunofficialโ allow unofficial extensions.experimentalโ 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. ๐จ Bestie I need you to actually read that one, it's not a drill.
๐ฆ Format stream specifiers ๐ฆ
Format stream specifiers allow selection of one or more streams that match specific properties. It's giving "choose your fighter." 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. So if you want the full lore, that's where it lives.
๐ธ DEMUXERS ๐ธ
Demuxers are configured elements in FFmpeg that can read the multimedia streams from a particular type of file. Think of them as the little readers that crack open a file type and hand you the streams inside โ each one knowing its own format's whole personality. โจ
When you configure your FFmpeg build, literally all the supported demuxers are enabled by default โ slay, no setup needed ๐
. Wanna see the whole roster? Hit up the configure option --list-demuxers and it'll spill the entire list.
You can also turn the whole squad off with --disable-demuxers, then selectively let one back in with --enable-demuxer=DEMUXER, or kick a single one out with --disable-demuxer=DEMUXER. Pick your fighters, bestie ๐ฎ.
Oh and the -demuxers option of the ff* tools will show you the list of enabled demuxers. Want a combined glow-up list of enabled demuxers and muxers? That's -formats. Both, together, iconic.
And now โ the description of some of the currently available demuxers. Buckle up ๐ฆ.
๐ธ aa ๐ธ
Audible Format 2, 3, and 4 demuxer.
This one's whole job is demuxing Audible Format 2, 3, and 4 (.aa) files. That's it, that's the vibe.
๐ง aac ๐ง
Raw Audio Data Transport Stream AAC demuxer.
This demuxer is used to demux an ADTS input containing a single AAC stream, along with any ID3v1/2 or APE tags hanging out in there. Tags included, bestie ๐ท๏ธ.
๐ฆ apng ๐ฆ
Animated Portable Network Graphics demuxer.
This one demuxes APNG files. Here's the tea: all headers โ except the PNG signature โ up to (but not including) the first fcTL chunk get transmitted as extradata. Then frames are split as being all the chunks between two fcTL ones, or between the last fcTL and IEND chunks. Frame boundaries, sorted โจ.
-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. Default of0imposes no limit, go wild ๐โโ๏ธ.-default_fpsint โ Default framerate in frames per second when none is specified in the file (0meaning as fast as possible). Default is15.
๐ asf ๐
Advanced Systems Format demuxer.
This demuxer handles ASF files and MMS network streams, both at once, multitasking queen ๐.
-no_resync_searchbool โ Do not try to resynchronize by looking for a certain optional start code. Like, just don't go looking, okay? ๐
๐ concat ๐
Virtual concatenation script demuxer.
Okay this one's kind of main character energy: it reads a list of files and other directives from a text file, and demuxes them one after the other, as if all their packets had been muxed together. Stitching the whole timeline into one, periodt โ๏ธ.
The timestamps in the files are adjusted so that the first file starts at 0 and each next file starts where the previous one finishes. Lowkey important caveat: this is done globally and may cause gaps if all streams do not have exactly the same length. Slight mismatch โ little timeline gaps, ngl ๐ญ.
All files must have the same streams (same codecs, same time base, etc.). No mixing and matching, bestie โ they gotta match fr fr.
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 can be used to override the duration stored in each file. Fix it manually if the vibes are off 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. Exactly. As. Is. No sneaky BOM ๐จ.
duration 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 is not available or accurate.
If the duration is set for all files, then it is possible to seek in the whole concatenated video.
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. Roughly-in-point vibes ๐ฌ.
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 the duration directive) 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. Overlap is real, bestie.
outpoint 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 that the demuxer will not output packets with a decoding timestamp greater or equal to Out point. >= Out point? Not on the menu ๐ โโ๏ธ.
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 be able to decode the earliest stream until Out point. Messy but honest ๐.
The duration of the files (if not specified by the duration directive) 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, use file_packet_meta instead. Old and busted ๐ซ .
file_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. The fresh new version, we stan ๐ซถ.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. Order said no, the id said yes ๐ .stream_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. id is 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 to 0, any file name is accepted. Chaos mode, your call ๐.
The default is 1.
auto_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 the h264_mp4toannexb bitstream filter to H.264 streams in MP4 format. This is necessary in particular if there are resolution changes. Resolution glow-up? Gotta convert, girl โจ.
segment_time_metadataโ If set to1, every packet will contain thelavf.concat.start_timeand thelavf.concat.durationpacket metadata values, which are thestart_timeand thedurationof 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
๐ dash ๐
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. Mirroring the metadata, cute ๐.
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). A whole dictionary of keys, spoiled ๐ .
๐ง dvdvideo ๐ง
DVD-Video demuxer, powered by libdvdnav and libdvdread.
Can directly ingest DVD titles, specifically sequential PGCs, 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 menu ripping, we respect the hustle ๐ซก.
Block devices (DVD drives), ISO files, and directory structures are accepted. Activate with -f dvdvideo in front of one of these inputs.
Big ol' warning: 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. Read that again, bestie ๐ญ.
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. Build it right or it's not gonna work โจ.
You will need to provide either the desired "title number" or exact PGC/PG coordinates. Lots of open-source DVD players and tools can help you dig those up. If you don't specify anything, the demuxer just defaults to title 1, which honestly works for a whole lot of discs. BUT โ because the format is so flexible, it's recommended you check manually. There are so many discs out there authored strangely or with straight-up invalid headers. ๐
If your input is an actual real-life DVD drive, heads up: some drives will silently fail on reading bad sectors from the disc and just hand you back random bits instead, which is effectively corrupt data. No cap. This is especially prominent on aging or rotting discs. You'd need a second pass and integrity checks to even detect the corruption. And btw โ this is not an FFmpeg issue.
๐ฌ Background ๐ฌ
DVD-Video is not a directly accessible, linear container format in the traditional sense. Instead, it allows for complex and programmatic playback of carefully muxed MPEG-PS streams that are stored in headerless VOB files. To the end-user, these streams are known simply as "titles", but the actual logical playback sequence is defined by one or more "PGCs", or Program Group Chains, within the title. The PGC is in turn comprised of multiple "PGs", or "Programs", which are the actual video segments (and for a typical video feature, sequentially ordered). The PGC structure, along with stream layout and metadata, are stored in IFO files that need to be parsed. PGCs can be thought of as playlists, in easier terms. ๐
An actual DVD player relies on user GUI interaction via menus and an internal VM to drive the direction of demuxing. Generally, the user would either navigate (via menus) or automatically be redirected to the PGC of their choice. During this process and the subsequent playback, the DVD player's internal VM also maintains a state and executes instructions that can create jumps to different sectors during playback. This is why libdvdnav is involved โ because a linear read of the MPEG-PS blobs on the disc (VOBs) is not enough to produce the right sequence in many cases. It's giving โจmain character energyโจ from the navigation layer.
There are many other DVD structures (a long subject) that will not be discussed here. NAV packets, in particular, are handled by this demuxer to build accurate timing but not emitted as a stream. For a good high-level understanding, refer to: <https://code.videolan.org/videolan/libdvdnav/-/blob/master/doc/dvd_structures>
โ๏ธ Options โ๏ธ
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.chapter_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 to signal end at the last possible chapter.angleint โ the video angle number, referring to what is essentially an additional video stream that is 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 at a particular angle in different regions. This option will not affect the region code of a real DVD drive, if used as an input. Not applicable to menus. Default is0, "world".menubool โ demux menu assets instead of navigating a title. Requires 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 is a VMG menu (root-level). Default is1, menu of the first VTS.pgcint โ the entry PGC to start playback, in conjunction withpg. Alternative to settingtitle. Chapter markers are not supported at this time. Must be explicitly set for menus. Default is0, automatically resolve from value oftitle.pgint โ the entry PG to start playback, in conjunction withpgc. Alternative to settingtitle. Chapter markers are not supported at this time. Default is1, the first PG of the PGC.preindexbool โ enable this to have 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. This is non-ideal extra work for real optical drives. It is 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 exist many discs with filler segments at the beginning of the PGC, often with junk data intended for controlling a real DVD player's buffering speed and with no other material data value. Not applicable to menus. Default is1, true.
๐ซ Examples ๐ซ
- 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> ...
๐ฎ ea
Electronic Arts Multimedia format demuxer. ๐น๏ธ
This format is used by various Electronic Arts games. iykyk.
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 which contains the alpha channel in addition to the ordinary video.
๐๏ธ imf
Interoperable Master Format demuxer. โจ
This demuxer presents 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. ๐ซถ
๐ฆ flv, live_flv, kux
Adobe Flash Video Format demuxer.
This demuxer is used to demux FLV files and RTMP network streams. In case of live network streams, if you force format, you may use live_flv option instead of flv to survive timestamp discontinuities. KUX is a 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. The little looping icon that it is. ๐
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 hundredth of seconds. Range is0to65535. Default value is65535(nearly eleven minutes), 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 information 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 overlay filter is used to end the output video at the length of the shortest input file, which in this case is input.mp4 as the GIF in this example loops infinitely. ๐
๐ hls
HLS demuxer โ 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". ๐
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 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 exceptmpegts, which is always allowed. It is recommended to set the whitelists correctly instead of depending on extensions. Enabled by default.max_reloadโ maximum number of times a insufficient list is attempted to be reloaded. Default value is1000.m3u8_hold_countersโ the maximum number of times to loadm3u8when 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.
๐ผ๏ธ image2
Image file demuxer.
Okay so this demuxer reads from a list of image files, and the list is specified by a pattern. The syntax and the meaning of the pattern is specified by the pattern_type option. ๐ผ๏ธ
The pattern may contain a suffix which is used to automatically determine the format of the images contained in the files.
The size, the pixel format, and the format of each image must be the same for all the files in the sequence โ like, all of them, no mixing, bestie. ๐ โโ๏ธ
This demuxer accepts the following options:
framerateโ sets the frame rate for the video stream. Defaults to25.loopโ if set to1, it loops over the input. Default value is0.pattern_typeโ selects the pattern type used to interpret the filename you handed it. It accepts one of these values:noneโ disables pattern matching, so the video will only contain the specified image. You should use this option if you don't want to create sequences from multiple images and your filenames may contain special pattern characters. ๐sequenceโ selects a sequence pattern type, used to specify a sequence of files indexed by sequential numbers. A sequence pattern may contain the string"%d"or"%0Nd", which specifies the position of the characters representing a sequential number in each filename matched by the pattern. If the form"%d0Nd"is used, the string representing the number in each filename is 0-padded and N is 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"%d"or"%0Nd", the first filename of the file list specified by the pattern must contain a number inclusively contained betweenstart_numberandstart_number+start_number_range-1, and all the following numbers must be sequential. For example the pattern"img-%03d.bmp"will match a sequence of filenames of the formimg-001.bmp,img-002.bmp, ...,img-010.bmp, etc.; the pattern"i%%m%%g-%d.jpg"will 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 must not necessarily contain"%d"or"%0Nd"โ for example to convert a single image fileimg.jpegyou can employ the command:
ffmpeg -i img.jpeg img.png
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. ๐- Default value is
sequence.
pixel_formatโ sets the pixel format of the images to read. If not specified, the pixel format is guessed from the first image file in the sequence.start_numberโ sets the index of the file matched by the image file pattern to start to read from. 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, will set frame timestamp to modification time of 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, will set frame timestamp to the modification time of the image file in nanosecond precision. โฑ๏ธvideo_sizeโ sets the video size of the images to read. If not specified, the video size is guessed from the first image file in the sequence.export_path_metadataโ if set to1, 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
- 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 100 in the sequence:
ffmpeg -framerate 10 -start_number 100 -i 'img-%03d.jpeg' out.mkv
- Read images matching the
"*.png"glob pattern, that is all the files terminating with the".png"suffix:
ffmpeg -framerate 10 -pattern_type glob -i "*.png" out.mkv
๐ฎ libgme
The Game Music Emu library is a collection of video game music file emulators. Nostalgia unlocked fr fr ๐น๏ธ
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, so pick your fave wisely. Track indexes start at0. Default is to pick the first track. Number of tracks is exported astracksmetadata 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 ๐ญ. 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
ModPlug based module demuxer.
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. โจ
It accepts the following options:
noise_reductionโ applies a simple low-pass filter. Can be1(on) or0(off). Default is0.reverb_depthโ sets amount of reverb. Range0-100. Default is0.reverb_delayโ sets 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. ๐bass_rangeโ sets cutoff i.e. 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 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 ๐ฌ). Default is5 MiB.video_stream_exprโ string which is evaluated using theevalAPI to assign colors to the generated video stream. Variables which can be used are"x","y","w","h","t","speed","tempo","order","pattern"and"row".video_streamโ generate video stream. Can be1(on) or0(off). Default is0.video_stream_wโ sets video frame width in 'chars' where one char indicates 8 pixels. Range is20-512. Default is30.video_stream_hโ sets video frame height in 'chars' where one char indicates 8 pixels. Range is20-512. Default is30.video_stream_ptxtโ print metadata on video stream. Includes"speed","tempo","order","pattern","row"and"ts"(time in ms). Can be1(on) or0(off). Default is1.
๐ผ libopenmpt
libopenmpt based module demuxer.
See <https://lib.openmpt.org/libopenmpt/> for more information.
Some files have multiple subsongs (tracks), and this can be set with the subsong option. ๐
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.layoutโ sets the channel layout. Valid values are 1, 2, and 4 channel layouts. The default value isSTEREO.sample_rateโ sets the sample rate for libopenmpt to output. Range is from1000toINT_MAX. The value default is48000.
๐บ mcc
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 ๐. You can change it to return all VANC data in a "SMPTE_436M_ANC" data stream by setting -eia608_extract 0.
Examples
- 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. ๐
- 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.
๐ฌ mov/mp4/3gp
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). The whole iconic family ๐
Registered extensions: mov, mp4, m4a, 3gp, 3g2, mj2, psp, m4b, ism, ismv, isma, f4v
Options
This demuxer accepts the following options:
enable_drefsโ enable loading of external tracks, disabled by default. Enabling this can theoretically leak information in some use cases. โ ๏ธ Like, be aware.use_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. No cap, don't just flip this on for random files.seek_streams_individuallyโ when seeking, identify the closest point in each stream individually and demux 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 ignore 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 modify the stream index to reflect the timeline described by the edit list."ignore_editlist"must be set tofalsefor this option to be effective. If both"ignore_editlist"and 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 okay so this one just tells it to not parse chapters at all, and yes that includes those lil GoPro 'HiLight' tags/moments ๐ฌ. Heads up tho: chapters only get parsed when the input is seekable in the first place. Default isfalse.use_mfra_forโ for seekable fragmented input, this sets the fragment's starting timestamp from the media fragment random access box, if it's there. The options are:autoโ auto-detect whether to set mfra timestamps as PTS or DTS (this is the default) โจdtsโ 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, this sets the fragment's starting timestamp tobaseMediaDecodeTimefrom thetfdtbox. Default is enabled, which means it'll prefer using thetfdtbox to set DTS ๐ . Disable it and it'll useearliest_presentation_timefrom thesidxbox instead. Either way, the timestamp from themfrabox gets used if it's available anduse_mfra_foris set toptsordts.export_allโ exports unrecognized boxes inside the udta box as metadata entries. The first four characters of the box type become the key ๐. Default isfalse.export_xmpโ exports the entire contents of the XMP_ box and uuid box as a string with the key"xmp". Small catch: ifexport_allis set and this option isn't, the contents of the XMP_ box still get exported, but with the key"XMP_"instead. Default isfalse.activation_bytesโ the 4-byte key required to decrypt Audible AAX and AAX+ files. See the Audible AAX subsection below ๐ง.audible_fixed_keyโ the fixed key used for handling Audible AAX/AAX+ files. It's been pre-set already, so you really shouldn't need to specify it.decryption_keyโ default 16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7) ๐.decryption_keysโ a 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).max_stts_deltaโ so sometimes a trak's stts box has these very high sample deltas that are actually intended, but usually they're written in error, or they're used to stash a negative value for dts correction when treated as signed 32-bit integers ๐ซ . This option lets you set an upper limit, and beyond that the delta gets clamped to1. 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 the uint32 range.
interleaved_readโ interleaves packets from multiple tracks right at the demuxer level. For badly interleaved files, this prevents playback issues caused by large gaps between packets in different tracks, since MOV/MP4 don't have packet placement requirements ๐. But โ and it's a big but โ this can cause excessive seeking on very badly interleaved files, because of all the seeking between tracks. So disabling it may prevent I/O issues, at the expense of playback.
๐ง Audible AAX
Audible AAX files are encrypted M4B files, and you can decrypt them by specifying a 4 byte activation secret. Like so:
ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
๐ mpegts
MPEG-2 transport stream demuxer. This demuxer accepts the following options:
resync_sizeโ sets the size limit for looking up a new synchronization. Default value is65536.skip_unknown_pmtโ skips PMTs for programs not defined in the PAT. Default value is0.fix_teletext_ptsโ overrides 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, so set this option to0if you want your teletext packet PTS and DTS values left untouched ๐.ts_packetsizeโ output option carrying the raw packet size in bytes. It shows the detected raw packet size โ you literally cannot set this yourself, bestie.scan_all_pmtsโ scan and combine all PMTs. The value is an integer from-1to1(-1means automatic setting,1means enabled,0means disabled). Default value is-1.merge_pmt_versionsโ reuses existing streams when a PMT's version gets updated and elementary streams move to different PIDs. Default value is0.max_packet_sizeโ sets the maximum size, in bytes, of a packet emitted by the demuxer. Payloads above this size get split across multiple packets. Range is184toINT_MAX/2. Default is204800bytes.
๐ผ๏ธ mpjpeg
MJPEG encapsulated in multi-part MIME demuxer. This one lets you read MJPEG where each frame is represented as a part of a multipart/x-mixed-replace stream โจ.
strict_mime_boundaryโ the default implementation applies a relaxed standard to multi-part MIME boundary detection, so that we don't regress with the numerous existing endpoints out there not generating a proper MIME MJPEG stream ๐ญ. Turning this option on by setting it to1results in a stricter check of the boundary value.
๐ฅ rawvideo
Raw video demuxer. This demuxer lets you read raw video data โ and because there's no header specifying the assumed video parameters, you have to specify them yourself in order to decode the data correctly. No cap.
This demuxer accepts the following options:
framerateโ sets the input video frame rate. Default value is25.pixel_formatโ sets the input video pixel format. Default value is"yuv420p".strideโ sets the 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 sets the input video size. This value must be specified explicitly.
For example, 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, use the command:
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", with 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
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 ๐. For more info on the format, see .
This demuxer implements the specification as of March 2024, which has been stable and unchanged since April 2014. Iconic.
โจ Examples
- Render CC to ASS using the built-in decoder:
ffmpeg -i CC.rcwt.bin CC.ass
Note that if your output appears to be empty, you may have to manually set the decoder's data_field option to pick the desired CC substream ๐.
- Convert an RCWT backup to Scenarist (SCC) format:
ffmpeg -i CC.rcwt.bin -c:s copy CC.scc
Note that the SCC format does not support all of the possible CC extensions that can be stored in RCWT (such as EIA-708) ๐.
๐ง sbg
SBaGen script demuxer. This demuxer reads the script language used by SBaGen <http://uazu.net/sbagen/> to generate binaural beats sessions ๐. A SBG script looks like that:
-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
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 ๐ซถ. On the other hand, 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 time the script is read, and the script layout gets frozen according to that reference. Which means: if the script is directly played, the actual times will match the absolute timestamps up to the sound controller's clock accuracy โ but if the user somehow pauses the playback or seeks, all times get shifted accordingly. Facts.
๐บ tedcaptions
JSON captions used for <http://www.ted.com/>.
TED does not provide links to the captions, but they can be guessed from the page ๐. The file tools/bookmarklets.html from the FFmpeg source tree contains a bookmarklet to expose them.
This demuxer accepts the following option:
start_timeโ sets 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 they include a 15s intro.
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
Vapoursynth wrapper.
Due to security concerns, Vapoursynth scripts will not be autodetected, so the input format has to be forced ๐ค. For ff* CLI tools, add -f vapoursynth before the input -i yourscript.vpy.
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 is1 MiB.
๐ต w64
Sony Wave64 Audio demuxer. This demuxer accepts the following options:
max_sizeโ see the same option for thewavdemuxer.
๐ wav
RIFF Wave Audio demuxer. This demuxer accepts the following options:
max_sizeโ specifies 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 ๐.
๐ METADATA ๐
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 with the metadata muxer/demuxer. Itโs giving โnotes app but for media tags.โ ๐
The file format goes like this:
- 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 the 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 the 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, with a trailing space, and value isbar, with a leading space).
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. The workflow is lowkey iconic, ngl.
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
โจ PROTOCOL OPTIONS โจ
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. Cute, right? ๐ซถ
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."ALL"matches all protocols. Protocols prefixed by-are disabled. All protocols are allowed by default but protocols used by another protocol (nested protocols) are restricted to a per protocol subset.
๐ PROTOCOLS ๐
Protocols are configured elements in FFmpeg that enable access to resources that require specific protocols. Itโs basically the backstage pass system for I/O. ๐๏ธ
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.
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.
A description of the currently available protocols follows. Buckle up, bestie. ๐ฆ
๐ amqp
Advanced Message Queueing Protocol (AMQP) version 0-9-1 is a broker based publish-subscribe communication protocol.
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.
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 /.
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.
The following options are supported:
exchangeโ Sets the exchange to use on the broker. RabbitMQ has several predefined exchanges:"amq.direct"is the default exchange, where the publisher and subscriber must have a matchingrouting_key;"amq.fanout"is the same as a broadcast operation (i.e. the data is forwarded to all queues on the fanout exchange independent of therouting_key); and"amq.topic"is similar to"amq.direct", but allows for more complex pattern matching (refer to the RabbitMQ documentation).routing_keyโ Sets the routing key. The default value is"amqp". The routing key is used on the"amq.direct"and"amq.topic"exchanges 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 anint). 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.connection_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 to"persistent"(2). This is the default value. Messages may be written to the broker's disk depending on its setup.non-persistentโ Delivery mode set to"non-persistent"(1). Messages will stay in broker's memory unless the broker is under memory pressure.
โก async
Asynchronous data filling wrapper for input stream. It fills data in a background thread, to decouple I/O operation from demux thread. Main character energy for your I/O. ๐
async:<URL>
async:http://host/resource
async:cache:http://host/resource
๐ฟ bluray
Read BluRay playlist.
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
๐๏ธ cache
Caching wrapper for input stream. It caches the input stream to temporary file. It brings seeking capability to live streams. No cap, itโs literally giving rewind to the live vibe. โช
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>
๐ concat
Physical concatenation protocol. Read and seek from many resources in sequence as if they were a unique resource.
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. Shells stay dramatic, we love that for them. ๐
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.
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
๐ crypto
AES-encrypted stream reading protocol.
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>
๐งฌ data
Data in-line in the URI. See http://en.wikipedia.org/wiki/Data_URI_scheme. Itโs the โeverything is a URI if you believe hard enoughโ protocol. ๐
For example, to convert a GIF file given inline with ffmpeg:
ffmpeg -i "data:image/gif;base64,R0lGODdhCAAIAMIEAAAAAAAA//8AAP//AP///////////////ywAAAAACAAIAAADF0gEDLojDgdGiJdJqUX02iB4E8Q9jUMkADs=" smiley.png
๐๏ธ fd
File descriptor access protocol.
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 corresponds to a regular file. fd protocol doesn't support passing a file descriptor via URL for security.
This protocol accepts the following options:
blocksizeโ Sets the max block size for I/O ops, in bytes. Default is"INT_MAX", which means the requested block size is literally not limited. Setting it reasonably low improves how fast the user termination request gets handled, which is super valuable if data transmission is slow. ๐ขfdโ Set file descriptor.
๐ธ file
File access protocol, bestie. Read from or write to a file. ๐
A file URL can look like this:
file:<filename>
where filename is the path of the file to read.
An URL that does not have a protocol prefix will be assumed to be a file URL. Depending on the build, an URL that looks like a Windows path with the drive letter at the beginning will also be assumed to be a file URL (usually not the case in builds for unix-like systems). ๐ชโจ
For example, to read from a file input.mpeg with ffmpeg, use the command:
ffmpeg -i file:input.mpeg output.mpeg
This protocol accepts the following options:
truncateโ Truncate existing files on write, if set to1. A value of0prevents truncating. Default value is1. โ๏ธblocksizeโ 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, which is valuable for files on slow medium. ๐followโ If set to1, the protocol will retry reading at the end of the file, allowing reading files that still are being written. In order for this to terminate, you either need to use therw_timeoutoption, or use the interrupt callback (for API users). ๐seekableโ Controls if seekability is advertised on the file.0means non-seekable,-1means auto (seekable for normal files, non-seekable for named pipes).
Many demuxers handle seekable and non-seekable resources differently, overriding this might speed up opening certain files at the cost of losing some features (e.g. accurate seeking). ๐ฏ
pkt_sizeโ Set 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. ๐
For reading, if explicitly set, 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.
๐ฆ ftp
FTP (File Transfer Protocol). Read from or write to remote resources using FTP protocol. ๐ก
Following syntax is required:
ftp://[user[:password]@]server[:port]/path/to/remote/resource.mpeg
This protocol accepts the following options.
timeoutโ Set timeout in microseconds 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. โณftp-userโ Set a user to be used for authenticating to the FTP server. This is overridden by the user in the FTP URL. ๐คftp-passwordโ Set 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. ๐ftp-anonymous-passwordโ Password used when login as anonymous user. Typically an e-mail address should be used. ๐งftp-write-seekableโ Control seekability of connection during encoding. If set to1the resource is supposed to be seekable, if set to0it is assumed not to be seekable. Default value is0. ๐๏ธ
NOTE: Protocol can be used as output, but it is recommended to not do it, unless special care is taken (tests, customized server configuration etc.). Different FTP servers behave in different way during seek operation. ff* tools may produce incomplete content due to server limitations. ๐
๐ง gopher
Gopher protocol.
๐ gophers
Gophers protocol. The Gopher protocol with TLS encapsulation. ๐
๐ http
HTTP (Hyper Text Transfer Protocol). This protocol accepts the following options:
seekableโ Control seekability of connection. If set to1the resource is supposed to be seekable, if set to0it is assumed not to be seekable, if set to-1it will try to autodetect if it is seekable. Default value is-1. ๐chunked_postโ If set to1use chunked Transfer-Encoding for posts, default is1. ๐ฆhttp_proxyโ set HTTP proxy to tunnel through e.g.http://example.com:1234. ๐ฐ๏ธheadersโ Set custom HTTP headers, can override built in default headers. The value must be a string encoding the headers. โ๏ธcontent_typeโ Set a specific content type for the POST messages or for listen mode. ๐ท๏ธuser_agentโ Override the User-Agent header. If not specified the protocol will use a string describing the libavformat build. ("Lavf/<version>") ๐ต๏ธrefererโ Set the Referer header. Include'Referer: URL'header in HTTP request. ๐multiple_requestsโ Use persistent connections if set to1, default is0. โป๏ธrequest_sizeโ Limit the size of requests made. This is useful for some pathological servers that throttle unbounded range requests, as well as when expecting to seek frequently. Disabled (set to0) by default.
Note that if enabling this option, it's strongly recommended to also enable the multiple_requests option, as well as setting short_seek_size to the same value or higher. Doing so allows FFmpeg to reuse a single HTTP connection wherever possible. ๐ซถ
initial_request_sizeโ Limit 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. Lasts until the demuxer makes a read request larger than this size (without a seek in between), after which the implementation will continue using requests as usual. Disabled (set to0) by default.
Note that if enabling this option, it's strongly recommended to also enable the multiple_requests option, as well as setting short_seek_size to the same value or higher. ๐
post_dataโ Set custom HTTP post data. ๐ฎmime_typeโ Export the MIME type. ๐ท๏ธhttp_versionโ Exports the HTTP response version number. Usually"1.0"or"1.1". ๐ขcookiesโ Set 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. ๐ชicyโ If set to1request 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 is1. ๐ปicy_metadata_headersโ If the server supports ICY metadata, this contains the ICY-specific HTTP reply headers, separated by newline characters. ๐icy_metadata_packetโ If the server supports ICY metadata, andicywas set to1, this contains the last non-empty metadata packet sent by the server. It should be polled in regular intervals by applications interested in mid-stream metadata updates. โฑ๏ธmetadataโ Set an exported dictionary containing Icecast metadata from the bitstream, if present. Only useful with the C API. ๐งauth_typeโ Set HTTP authentication type. No option for Digest, since this method requires getting nonce parameters from the server first and can't be used straight away like Basic. ๐noneโ Choose the HTTP authentication type automatically. This is the default. โจbasicโ Choose the HTTP basic authentication.
โ ๏ธ Security tea: 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. ๐จ
send_expect_100โ Send anExpect: 100-continueheader for POST. If set to1it will send, if set to0it won't, if set to-1it will try to send if it is applicable. Default value is-1. ๐จlocationโ An exported dictionary containing the content location. Only useful with the C API. ๐offsetโ Set initial byte offset. ๐งญend_offsetโ Try to limit the request to bytes preceding this offset. ๐methodโ 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 do not 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. ๐ง
reconnectโ Reconnect automatically when disconnected before EOF is hit. ๐reconnect_at_eofโ If set then eof is treated like an error and causes reconnection, this is useful for live / endless streams. โพ๏ธreconnect_on_network_errorโ Reconnect automatically in case of TCP/TLS errors during connect. ๐reconnect_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'. ๐reconnect_streamedโ If set then even streamed/non seekable streams will be reconnected on errors. ๐reconnect_delay_maxโ Set the maximum delay in seconds after which to give up reconnecting. โฒ๏ธreconnect_max_retriesโ Set the maximum number of times to retry a connection. Default unset. ๐reconnect_delay_total_maxโ Set the maximum total delay in seconds after which to give up reconnecting. โฑ๏ธrespect_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. ๐ซกlistenโ set this to1and boom, you've got an experimental HTTP server ๐ . 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 to2and you get an experimental multi-client HTTP server โ but heads up bestie, that one is not yet implemented inffmpeg.cso you literally must not use it as a command line option ๐.
# 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 that a client requested, when the experimental HTTP server is the one in play.reply_codeโ the HTTP code that gets sent back to the client, again only when the experimental HTTP server is running the show.short_seek_sizeโ sets the threshold, in bytes, for when readahead should be preferred over doing a seek + a brand new HTTP request. Genuinely useful, like, for making sure you stay on the same connection while reading big video packets with lil baby audio packets sandwiched in between ๐ซถ.
๐ช HTTP Cookies ๐ช
Some HTTP requests are gonna get straight-up denied unless you pass cookie values along with the request ๐ญ. The cookies option is how you hand those over. Bare minimum, every cookie has to specify a value plus a path and a domain. Any HTTP request matching both the domain and the path will automatically get the cookie value dropped into the HTTP Cookie header field. You can separate multiple cookies with a newline. Slay.
The required syntax to play a stream while specifying a cookie is:
ffplay -cookies "nlqptid=nltid=tsn; path=/; domain=somedomain.com;" http://somedomain.com/somestream.m3u8
๐ง Icecast ๐ง
Icecast protocol โ for streaming to Icecast servers.
This protocol accepts the following options:
ice_genreโ sets the stream genre.ice_nameโ sets the stream name.ice_descriptionโ sets the stream description.ice_urlโ sets the stream's website URL.ice_publicโ sets whether the stream should be public or not. Default is0(aka not public, private vibes only).user_agentโ overrides the User-Agent header. If you don't specify one, a string of the form"Lavf/<version>"gets used.passwordโ sets the Icecast mountpoint password.content_typeโ sets the stream content type. You must set this if it's anything other thanaudio/mpeg.legacy_icecastโ enables support for Icecast versions< 2.4.0, which don't support the HTTP PUT method and use the SOURCE method instead.tlsโ establishes a TLS (HTTPS) connection to Icecast.
icecast://[<username>[:<password>]@]<server>:<port>/<mountpoint>
๐ช ipfs ๐ช
InterPlanetary File System (IPFS) protocol support, bestie. You can access files stored on the IPFS network through what are called gateways โ these are http(s) endpoints. This protocol wraps the IPFS native protocols (ipfs:// and ipns://) so they get sent to one of those gateways. Users can (and honestly should) host their own node, which means this protocol will use your local gateway to reach files on the IPFS network ๐.
This protocol accepts the following options:
gatewayโ defines which gateway to use. When it's not set, the protocol first tries to locate the local gateway by checking$IPFS_GATEWAY, then$IPFS_PATH, then"$HOME/.ipfs/", in that exact order ๐
You can use this protocol in 2 ways. With IPFS:
ffplay ipfs://<hash>
Or with the IPNS protocol (IPNS is the mutable version of IPFS):
ffplay ipns://<hash>
๐บ mmst ๐บ
MMS (Microsoft Media Server) protocol over TCP. That's it, that's the whole vibe.
๐บ mmsh ๐บ
MMS (Microsoft Media Server) protocol over HTTP.
The required syntax is:
mmsh://<server>[:<port>][/<app>][/<playpath>]
๐ md5 ๐
MD5 output protocol.
It computes the MD5 hash of the data being written, and on close it writes that hash to the designated output โ or to stdout if you didn't specify one. Super handy for testing muxers without actually writing a real file โจ.
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:
โ ๏ธ Heads up: some formats (typically MOV) need the output protocol to be seekable, so they will fail with the MD5 output protocol. Not a drill ๐
๐ฐ pipe ๐ฐ
UNIX pipe access protocol. Read and write from UNIX pipes, iconic behaviour.
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 isn't specified at all, the stdout file descriptor is used by default for writing, and stdin for reading ๐ซถ.
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 sets the I/O operation maximum block size, in bytes. Default value is"INT_MAX", which means the requested block size doesn't get limited at all. Setting this reasonably low improves how fast your termination requests get reacted to โ genuinely valuable when data transmission is slow ๐.fdโ sets the file descriptor.
โ ๏ธ And again, bestie: some formats (typically MOV) require the output protocol to be seekable, so they'll fail with the pipe output protocol. Same energy as the MD5 situation ๐ญ
๐ก prompeg ๐ก
Pro-MPEG Code of Practice #3 Release 2 FEC protocol.
The Pro-MPEG CoP#3 FEC is a 2D parity-check forward error correction mechanism for MPEG-2 Transport Streams sent over RTP. Fancy, right? ๐
This protocol must be used in conjunction with the "rtp_mpegts" muxer and the "rtp" protocol. No solo missions.
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)d=nโ the number of rows (4-20,LxD <= 100)
Example usage:
-f rtp_mpegts -fec prompeg=l=8:d=4 rtp://<hostname>:<port>
๐ rist ๐
Reliable Internet Streaming Transport protocol. Reliable, like your bestie who always texts back.
The accepted options are:
rist_profileโ supported values:simplemainโ this one is the default.advanced
buffer_sizeโ sets the internal RIST buffer size in milliseconds, used for retransmission of data. Default value is0, which means "use the librist default" (1 sec). Maximum value is 30 seconds.fifo_sizeโ size of the librist receiver output fifo, in number of packets. This must be a power of 2. Defaults to8192(versus the librist default of1024).overrun_nonfatal=1|0โ survive in case of a librist fifo buffer overrun. Default value is0.pkt_sizeโ sets the maximum packet size for sending data.1316by default.log_levelโ sets the loglevel for RIST logging messages. You only need to set this if you explicitly want to enable debug level messages or packet loss simulation โ otherwise the regular loglevel is respected ๐ซถ.secretโ set an override of the encryption secret; by default it's unset.encryptionโ set the encryption type; by default it's disabled. Acceptable values are128and256.
๐ฅ rtmp ๐ฅ
Real-Time Messaging Protocol.
The Real-Time Messaging Protocol (RTMP) is used for streaming multimedia content across a TCP/IP network. Classic, iconic, still here.
The required syntax is:
rtmp://[<username>:<password>@]<server>[:<port>][/<app>][/<instance>][/<playpath>]
The accepted parameters are:
usernameโ an optional username (mostly for publishing).passwordโ an optional password (mostly for publishing).serverโ the address of the RTMP server.portโ the number of the TCP port to use (by default it's1935).appโ 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 also override the value parsed from the URI through the"rtmp_app"option ๐playpathโ the path or name of the resource to play, with reference to the application specified in app; it may be prefixed by"mp4:". You can also override the value parsed from the URI through the"rtmp_playpath"option.listenโ act as a server, listening for an incoming connection.timeoutโ maximum time to wait for the incoming connection. Implies listen ๐ซถ
Additionally, the following parameters can be set via command line options (or in code via "AVOption"s):
rtmp_appโ name of the application to connect to on the RTMP server. This option overrides the parameter specified in the URI.rtmp_bufferโ set the client buffer time in milliseconds. The default is3000.rtmp_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 โBfor Boolean,Nfor number,Sfor string,Ofor object, orZfor null โ 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 ๐คrtmp_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 โจrtmp_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>).)rtmp_flush_intervalโ how many packets get flushed in the same request (this one's RTMPT only bestie ๐ ). Default is10.rtmp_liveโ says "this media is a live stream, ok?". When it's live, no resuming and no seeking โ like, it is what it is, you can't scrub it ๐ญ. Default value is"any", which means the subscriber first tries to play the live stream specified in the playpath; if a live stream of that name isn't found, it plays the recorded stream instead. The other possible values are"live"and"recorded".rtmp_pageurlโ URL of the web page where the media was embedded. By default, no value will be sent.rtmp_playpathโ the stream identifier to play or to publish. This option overrides the parameter specified in the URI.rtmp_subscribeโ name of the live stream to subscribe to. By default no value will be sent. It's only sent if the option is specified or ifrtmp_liveis set tolive.rtmp_swfhashโ SHA256 hash of the decompressed SWF file (32 bytes).rtmp_swfsizeโ size of the decompressed SWF file, required for SWFVerification.rtmp_swfurlโ URL of the SWF player for the media. By default no value will be sent.rtmp_swfverifyโ URL to the player swf file; it computes the hash/size automatically โจ.rtmp_tcurlโ 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 that reduces the efficiency / effect of TCP_NODELAY. So likeโฆ it's giving "the setting is there but the vibe is mid" ๐.
tcp_keepalive=1|0โ enables the TCP keepalive mechanism to detect dead peers and help maintain long-lived idle connections ๐ซถ. 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.
So 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
And 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 ๐
Encrypted Real-Time Messaging Protocol.
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 โจstreamingโจ.
rtmps ๐
Real-Time Messaging Protocol over a secure SSL connection.
The Real-Time Messaging Protocol (RTMPS) is used for streaming multimedia content across an encrypted connection. Secure lil guy ๐.
rtmpt ๐ง
Real-Time Messaging Protocol tunneled through HTTP.
The Real-Time Messaging Protocol tunneled through HTTP (RTMPT) is used for streaming multimedia content within HTTP requests to traverse firewalls. Firewall said "no" and RTMPT said "bet" ๐ .
rtmpte ๐
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.
rtmpts โญ
Real-Time Messaging Protocol tunneled through HTTPS.
The Real-Time Messaging Protocol tunneled through HTTPS (RTMPTS) is used for streaming multimedia content within HTTPS requests to traverse firewalls.
libsmbclient ๐ฆ
libsmbclient permits one to manipulate CIFS/SMB network resources.
Following syntax is required, no cap:
smb://[[domain:]user[:password@]]server[/share[/path[/file]]]
This protocol accepts the following options.
timeoutโ sets the timeout in milliseconds 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.truncateโ truncate existing files on write, if set to1. A value of0prevents truncating. Default value is1.workgroupโ sets the workgroup used for making connections. By default the workgroup is not specified.
For more information see: <http://www.samba.org/>.
libssh ๐ธ
Secure File Transfer Protocol via libssh.
Read from or write to remote resources using SFTP protocol.
Following syntax is required:
sftp://[user[:password]@]server[:port]/path/to/remote/resource.mpeg
This protocol accepts the following options.
timeoutโ sets the timeout 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.truncateโ truncate existing files on write, if set to1. A value of0prevents truncating. Default value is1.private_keyโ specifies 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 ๐
Real-Time Messaging Protocol and its variants supported through librtmp.
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 ๐.
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).
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.
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 ๐
Real-time Transport Protocol.
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.
Options can also be specified via command line options (or in code via "AVOption"s).
The list of supported options follows, bestie โจ:
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 ๐.
local_rtcpport,localrtcpport=nโ 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.write_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 timeout (in microseconds) of socket I/O operations to n.
Important notes, don't skip these ๐ฅ:
- If
rtcpportis not set the RTCP port will be set to the RTP port value plus 1. - 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 plus 1.
rtsp ๐
Real-Time Streaming Protocol.
RTSP is not technically a protocol handler in libavformat, 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 ๐
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.
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 ๐ฆ
The following options are supported.
initial_pauseโ do not start playing the stream immediately if set to1. Default value is0.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.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, which is lowkey so useful for slipping past proxies and is widely used for security consideration, bestie ๐
You can specify multiple lower transport protocols, and in that case they get tried one at a time (so if the setup of one fails, the next one is tried, no big deal). For the muxer, only the tcp and udp options are supported, iykyk.
๐ฆ rtsp_flags
Set RTSP flags. The following values are accepted:
filter_srcโ accept packets only from the negotiated peer address and port. Like, boundaries, we stan ๐listenโ act as a server, listening for an incoming connection. main character energy frprefer_tcpโ try TCP for RTP transport first, if TCP is available as RTSP RTP transportsatip_rawโ export the raw MPEG-TS stream instead of demuxing it. The flag will simply write out the raw stream, with the original PAT/PMT/PIDs intact. no touchy, just vibes โจ
Default value is none.
๐ allowed_media_types
Set the media types to accept from the server. The following flags are accepted:
videoaudiodatasubtitle
By default it accepts all media types. generous queen ๐ซถ
๐ min_port
Set the minimum local UDP port. Default value is 5000.
๐ max_port
Set the maximum local UDP port. Default value is 65000.
๐ธ listen_timeout
Set the maximum timeout (in seconds) to establish an initial connection. Setting listen_timeout > 0 sets rtsp_flags to listen. Default is -1, which means an infinite timeout when listen mode is set. literally forever, bestie ๐ญ
๐ง reorder_queue_size
Set the number of packets to buffer for handling of reordered packets.
โญ timeout
Set the socket TCP I/O timeout in microseconds (yes, microseconds, do not come for me).
๐ฆ user_agent
Override the User-Agent header. If not specified, it defaults to the libavformat identifier string.
๐ buffer_size
Set the maximum socket buffer size in bytes.
When receiving data over UDP, the demuxer tries to reorder received packets (since they may arrive out of order, or packets may get lost totally โ rude, honestly). 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, the streams to display can be chosen with -vst n and -ast n for video and audio respectively, and can be switched on the fly by pressing v and a. iconic behaviour tbh ๐
โจ Examples โจ
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>
๐ sap
Session Announcement Protocol (RFC 2974). This is not technically a protocol handler in libavformat โ it's a muxer and demuxer. It's used for signalling of RTP streams, by announcing the SDP for the streams regularly on a separate port. it's giving "hey besties, stream's over here" ๐ข
๐ธ 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, the announcements are sent to the commonly used SAP announcement multicast address224.2.127.254(sap.mcast.net), orff0e::2:7ffeif destination is an IPv6 address.announce_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|1 โ 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 to1, to be able to receive the stream. The RTP stack in libavformat for receiving requires all streams to be sent on unique ports. so like, pick your fighter 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]
๐ฆ 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; 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. obsessed with the follow-through โจ
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]
๐ง 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.
Options can also can be specified via command line options (or in code via "AVOption"s). yes, both ways, we're flexible ๐
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. go off, unlimited ๐ซถ
โญ 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 "AVOption"s).
The list of supported options follows.
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). ngl this one's messy, but we move ๐ญffs=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) / 100ifinputbwis 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 version 1.3.0 this is the only flag to set the latency, however this is effectively equivalent to settingpeerlatency, when 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.-1infinite (CSRTCC limit is 30mbps),0relative to input rate (seeinputbw),>0absolute limit value. Default value is0(relative).mode=caller|listener|rendezvous โ connection mode.calleropens client connection.listenerstarts server to listen for incoming connections.rendezvoususe Rendez-Vous connection mode. Default value iscaller.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|0 โ 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 once it's gone it's gone bestieenforced_encryption=1|0 โ 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 the0-"INT_MAX".kmpreannounce=packetsโ this is the lil gap between "hey bestie here's ur new encryption key โจ" and the moment the switchover actually happens. Lowkey it also covers the next interval โ the one between switchover happening and the old key getting decommissioned. Default is-1, and-1means auto (0x1000in the srt library). Range is integers from0toINT_MAX. ๐snddropdelay=microsecondsโ the sender's extra delay before it starts dropping packets, added on top of the default drop delay time interval. Special value-1: don't drop packets on the sender at all. Not one, not ever. ๐payload_size=bytesโ sets the maximum declared size of a packet transferred 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 than 1456 bytes. ๐pkt_size=bytesโ alias forpayload_size. Same vibes, different name. ๐ฆpeerlatency=microsecondsโ the latency value (as described down inrcvlatency) that the sender side sets as a minimum value for the receiver. It's giving "here's the floor, bestie." โญpbkeylen=bytesโ sender encryption key length, in bytes. Can only be set to0,16,24and32. Enables sender encryption if not0. Not required on the receiver (set it to0there), key size is obtained from the sender in the HaiCrypt handshake. Default value is0. ๐ฅrcvlatency=microsecondsโ the time that should elapse since the moment when the packet was sent and the moment when it's delivered to the receiver application in the receiving function. Think of it as buffer time big enough to cover the time spent sending, unexpectedly extended RTT time, and the time needed to retransmit the lost UDP packet. The effective latency value will be the maximum of this option's value and the value ofpeerlatencyset by the peer side. Before version1.3.0this option was only available aslatency. ๐ญrecv_buffer_size=bytesโ set the UDP receive buffer size, expressed in bytes. ๐ซถsend_buffer_size=bytesโ set the UDP send buffer size, expressed in bytes. ๐ซถtimeout=microsecondsโ set raise error timeouts for read, write and connect operations. Heads up: 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 enabled on the receiver, it skips missing packets that haven't been delivered in time and delivers the following packets to the application when their time-to-play has come. It also sends a fake ACK to the sender. When 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 was automatically enabled in the sender if the receiver supports it. ๐sndbuf=bytesโ set the send buffer size, expressed in bytes. ๐ธrcvbuf=bytesโ set the receive buffer size, expressed in bytes.
Bestie listen to me: the receive buffer must not be greater than ffs. ๐จ
lossmaxttl=packetsโ the value up to which the Reorder Tolerance may grow. When Reorder Tolerance is> 0, then the packet loss report is delayed until that number of packets come in. Reorder Tolerance increases every time a "belated" packet has come, but it wasn't due to retransmission (that is, when UDP packets tend to come out of order), with the difference between the latest sequence and this packet's sequence, and not more than the value of this option. By default it's0, which means this whole mechanism is turned off, and the loss report is always sent immediately upon experiencing a "gap" in sequences. ๐งminversionโ the minimum SRT version that is required from the peer. A connection to a peer that does not satisfy the minimum version requirement will be rejected. Periodt.
The version format in hex is 0xXXYYZZ for x.y.z in human readable form. ๐
streamid=stringโ a string limited to 512 characters that can be set on the socket prior to connecting. This stream ID will be able to be retrieved by the listener side from the socket that is returned fromsrt_acceptand was connected by a socket with that set stream ID. SRT doesn't enforce any special interpretation of the contents of this string. Also 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 the matter of luck which one would win. ๐srt_streamid=stringโ alias forstreamidto avoid conflict with ffmpeg command line option. Crisis averted. ๐smoother=live|fileโ the type of Smoother used for the transmission for that socket, which is responsible for the transmission and congestion control. The Smoother type must be exactly the same on both connecting parties, otherwise the connection is rejected. No mismatched vibes allowed. ๐messageapi=1|0โ when set, this socket uses the Message API, otherwise it uses Buffer API. Note that in live mode (seetranstype) there's only message API available. In File mode you can choose to use one of two modes:- Stream API (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 will take care of any speed and congestion control. When receiving, you can also receive as many data as desired, the data not extracted will be waiting for the next call. There is no boundary between data portions in the Stream mode. ๐
- 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. ๐ฌ
transtype=live|fileโ sets the transmission type for the socket. Lowkey setting this option sets multiple other parameters to their default values as required for a particular transmission type. ๐live: 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, and limited to the value defined first inpayload_size(1316is default in this mode). There is no speed control in this mode, only the bandwidth control, if configured, in order to not exceed the bandwidth with the overhead transmission (retransmitted and control packets). ๐ฅfile: set options as for non-live transmission. Seemessageapifor further explanations. ๐
linger=secondsโ the number of seconds that the socket waits for unsent data when closing. Default is-1.-1means auto (off with0seconds in live mode, on with180seconds in file mode). The range for this option is integers in the0-INT_MAX. ๐ดtsbpd=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. โฐ
For more information see: <https://github.com/Haivision/srt>.
๐ srtp ๐
Secure Real-time Transport Protocol. Very secure, very demure. โจ
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 master key, the following 14 bytes are used as master salt. ๐
๐ฆ subfile ๐ฆ
Virtually extract a segment of a file or another stream. The underlying stream must be seekable โ no cap, if it can't seek, it can't do the thing. ๐ญ
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 end of file. ๐
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
๐ธ tee ๐ธ
Writes the output to multiple protocols. The individual outputs are separated by |. It's giving "why choose one when you can have both." ๐
tee:file://path/to/local/this.avi|file://path/to/local/that.avi
โญ tcp โญ
Transmission Control Protocol. The reliable one. The one who texts back. ๐ซถ
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. ๐
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. ๐local_addr=addrโ local IP address of a network interface used for tcp socket connect. ๐ฆlocal_port=portโ local port used for tcp socket connect. ๐ฆtimeout=microsecondsโ 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. โฐ
listen_timeout=millisecondsโ set listen timeout, expressed in milliseconds. โณrecv_buffer_size=bytesโ set receive buffer size, expressed in bytes. ๐send_buffer_size=bytesโ set send buffer size, expressed in bytes. ๐tcp_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 reduces the efficiency / effect of TCP_NODELAY. Ngl that's just how it is bestie. ๐
tcp_mss=bytesโ set maximum segment size for outgoing TCP packets, expressed in bytes. ๐ฆ
okay so real talk โ here's how you actually spin up a listening TCP connection with ffmpeg and then go vibe-check it with ffplay:
ffmpeg -i <input> -f <format> tcp://<hostname>:<port>?listen
ffplay tcp://<hostname>:<port>
๐ tls
Transport Layer Security (TLS) / Secure Sockets Layer (SSL). yes both names, it's giving legacy-acronym energy but we move ๐
The required syntax for a TLS/SSL url is literally:
tls://<hostname>:<port>[?<options>]
options is 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. clean URLs ate, no cap.
Options can also be specified via command line options (or in code via AVOptions).
The list of supported options follows, bestie:
ca_file,cafile=filenameโ a file holding certificate authority (CA) root certificates that you're treating as trusted. If the linked TLS library ships with a default, you might not need to specify this for verification to work โ 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, it tries to verify the peer we're talking to. Heads up tho: if you're using OpenSSL, this currently only makes sure that the peer certificate is signed by one of the root certificates in the CA database โ it does not validate that the certificate actually matches the host name we're trying to connect to. (With other backends, the host name is validated as well, so slay for them.)
This is disabled by default since it requires a CA database to be provided by the caller in many cases.
cert_file,cert=filenameโ 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=filenameโ a file containing the private key for the certificate. ๐listen=1|0โ if enabled, listen for connections on the provided port, and assume the server role in the handshake instead of the client role. main character energy fr.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>
๐ฐ๏ธ dtls
Datagram Transport Layer Security (DTLS).
The required syntax for a DTLS URL is:
dtls://<hostname>:<port>[?<options>]
options is 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).
DTLS shares most options with TLS, but operates over UDP instead of TCP. same vibes, different transport ๐ฆ
The list of supported options follows:
ca_file,cafile=filenameโ 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=filenameโ 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=filenameโ a file containing the private key for the certificate.cert_pem=stringโ certificate PEM string โจkey_pem=stringโ private key PEM string โจlisten=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=sizeโ 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 the 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>
๐ก udp
User Datagram Protocol. the classic. the icon. unreliable in the most lovable way.
The required syntax for an UDP URL is:
udp://<hostname>:<port>[?<options>]
options is 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).
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. iykyk ๐ง
The list of supported options follows:
buffer_size=sizeโ 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 is32 KBfor output,384 KBfor input. See alsofifo_size.bitrate=bitrateโ if set to nonzero, the output will have the specified constant bitrate if the input has enough packets to sustain it.burst_bits=bitsโ when usingbitratethis specifies the maximum number of bits in packet bursts.localport=portโ override the local UDP port to bind with.localaddr=addrโ local IP address of a network interface used for sending packets or joining multicast groups.pkt_size=sizeโ set the size in bytes of UDP packets.reuse=1|0โ explicitly allow or disallow reusing UDP sockets.ttl=ttlโ set the time to live value (for multicast only).dscp=dscpโ 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. lowkey a glow-up ngl.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. not me blocking an IP ๐ซfifo_size=unitsโ set the UDP receiving circular buffer size, expressed as a number of packets with size of188bytes. If not specified defaults to7*4096.overrun_nonfatal=1|0โ survive in case of UDP receiving circular buffer overrun. Default value is0.timeout=microsecondsโ 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 using188sized 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> ...
๐งฆ unix
Unix local socket. yes it's just a file path, and yes that's iconic of it.
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 AVOptions):
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.
๐ช๏ธ zmq
ZeroMQ asynchronous messaging using the libzmq library.
This library supports unicast streaming to multiple clients without relying on an external server. no middleman, we love to see it ๐ซถ
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. so chill about it โจ
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 bestie this one forces the maximum packet size for sending/receiving data, and the default is131,072bytes ๐ On the server side it sets the max size of packets sent via ZeroMQ, and on the clients it sets an internal buffer size for receiving packets. And listen โpkt_sizeon the clients should literally be equal to or greater thanpkt_sizeon the server, ok? Otherwise the received message may get truncated and that causes decoding errors ๐ญ no cap.
๐ธ DEVICE OPTIONS ๐ธ
So the libavdevice library gives you the exact same interface as libavformat, periodt. Like, an input device is considered like a demuxer, and an output device like a muxer, and the interface plus the generic device options are the same ones provided by libavformat (go peek at the ffmpeg-formats manual, iykyk).
On top of that, each input or output device may support its own so-called private options which are specific to that component ๐
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 for programmatic use. Multiple lanes, all valid โจ
๐ INPUT DEVICES ๐
Input devices are configured elements in FFmpeg that enable accessing the data coming from a multimedia device attached to your system ๐ฆ
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 the input devices using the configure option --disable-indevs, and selectively enable an input device using --enable-indev=INDEV, or you can disable a particular input device using --disable-indev=INDEV. Mix and match, she contains multitudes ๐
The option -devices of the ff* tools will display the list of supported input devices.
A description of the currently available input devices follows ๐
alsa
The ALSA (Advanced Linux Sound Architecture) input device ๐ง
To enable this input device during configuration you need libasound installed on your system.
This device allows capturing from an ALSA device, and 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.
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.channelsโ set the number of channels. Default is2.
android_camera
The Android camera input device ๐ฑ
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 allows capturing from all cameras on an Android device, which 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 ignored ๐
Generally the back facing camera has index 0 while the front facing camera has index 1 โ selfie mode activated ๐ซถ
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.
avfoundation
The AVFoundation input device ๐
AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >= 10.7 as well as on iOS.
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.
There are two device name aliases:
defaultโ select the AVFoundation default device of the corresponding type.noneโ do not record the corresponding media type. This is equivalent to specifying an empty device name or index.
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 isntsc, corresponding to a frame rate of30000/1001.-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 sends 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 0 and audio from audio device 0 into
out.avi:
$ ffmpeg -f avfoundation -i "0:0" out.avi
- Record video from video device 2 and audio from audio device 1 into
out.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
decklink
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.
DeckLink is very picky about the formats it supports, ngl. 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 to false. 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 to false.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.raw_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.
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.
Heads up bestie, this part picks up right in the middle of the DeckLink tea โ โ no new headings needed, we're still in there.
Note: DeckLink SDK 11.0 straight up replaced the duplex property with a profile property. So for the DeckLink Duo 2 and DeckLink Quad 2, a profile is shared between any 2 sub-devices that use the same connectors. For the DeckLink 8K Pro, a profile is shared between all 4 sub-devices. Meaning the DeckLink 8K Pro supports four profiles, periodt. ๐
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_format
The timecode type to include in the frame and video stream metadata. Gotta be one of none, rp188vitc, rp188vitc2, rp188ltc, rp188hfr, rp188any, vitc, vitc2, or serial. Defaults to none (aka not included, she's not showing up to the party).
So 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. Lowkey note that this is slightly different from the ordering used by the DeckLink API, which goes HFR, VITC1, LTC, VITC2. Don't mix them up bestie ๐
video_input
Sets the video input source. Must be unset, sdi, hdmi, optical_sdi, component, composite or s_video. Defaults to unset.
audio_input
Sets the audio input source. Must be unset, embedded, aes_ebu, analog, analog_xlr, analog_rca or microphone. Defaults to unset.
video_pts
Sets the video packet timestamp source. Must be video, audio, reference, wallclock or abs_wallclock. Defaults to video.
audio_pts
Sets the audio packet timestamp source. Must be video, audio, reference, wallclock or abs_wallclock. Defaults to audio.
draw_bars
If set to true, color bars get drawn in the event of a signal loss. Defaults to true.
โ ๏ธ This option is deprecated, bestie โ please use the signal_loss_action option instead. She's retired but still hanging around ๐
signal_loss_action
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.2,barsโ draw color bars on signal loss. Only supported for 8-bit input signals.3,repeatโ repeat the last video frame on signal loss.
Defaults to bars.
queue_size
Sets the maximum input buffer size in bytes. If the buffering reaches this value, incoming frames will be dropped, no cap. Defaults to 1073741824.
audio_depth
Sets the audio sample bit depth. Must be 16 or 32. Defaults to 16.
decklink_copyts
If set to true, timestamps are forwarded as they are without removing the initial offset. Defaults to false.
timestamp_align
Capture start time alignment in seconds. If set to nonzero, input frames are dropped till the system timestamp aligns with the configured value. An 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.
Ngl 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 case,timestamp_alignseconds. Defaults to0. ๐ญ
wait_for_tc (bool)
Drop frames till a frame with timecode is received. Sometimes serial timecode isn't received with the first input frame. If that happens, the stored stream timecode will be inaccurate. If this option is set to true, input frames are dropped till a frame with timecode is received. Option timecode_format must be specified. Defaults to false.
enable_klv(bool)
If set to true, 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 to false.
โจ Examples โจ
- List input devices:
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
๐ dshow ๐
Windows DirectShow input device. Yes, Windows besties, this one's for you ๐ซถ
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. Iconic behaviour honestly.
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. Like, it just won't, sorry ๐
video_size
Set the video size in the captured video.
framerate
Set the frame rate in the captured video.
sample_rate
Set the sample rate (in Hz) of the captured audio.
sample_size
Set the sample size (in bits) of the captured audio.
channels
Set the number of channels in the captured audio.
list_devices
If set to true, print a list of devices and exit.
list_options
If set to true, print a list of the selected device's options and exit.
video_device_number
Set the video device number for devices with the same name (starts at 0, defaults to 0).
audio_device_number
Set the audio device number for devices with the same name (starts at 0, defaults to 0).
pixel_format
Select the pixel format to be used by DirectShow. This may only be set when the video codec is not set or set to rawvideo.
audio_buffer_size
Set the 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 of 500ms). Setting this value too low can degrade performance. See also <http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx>
video_pin_name
Select the video capture pin to use by name or alternative name.
audio_pin_name
Select the audio capture pin to use by name or alternative name.
crossbar_video_input_pin_number
Select video input pin number for the crossbar device. This will be routed to the crossbar device's Video Decoder output pin.
Note that changing this value can affect future invocations (it sets a new default) until a system reboot occurs. She's got main character energy and she remembers ๐ฅ
crossbar_audio_input_pin_number
Select audio input pin number for the 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 a system reboot occurs. Same deal, bestie.
show_video_device_dialog
If set to true, 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 avoid green bars at the bottom, flickering scan lines, etc. And note that with some devices, changing these properties can also affect future invocations (sets new defaults) until a system reboot occurs. ๐
show_audio_device_dialog
If set to true, 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_dialog
If set to true, 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_dialog
If set to true, 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_dialog
If set to true, 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_dialog
If set to true, 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_load
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 use this, an audio capture source has to be specified, but it can be anything โ even a fake one. Fake it till you make it ๐
audio_device_save
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. Rude but that's the rule.
video_device_load
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 use this, a video capture source has to be specified, but it can be anything โ even a fake one.
video_device_save
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_timestamps
If set to false, the timestamp for video frames will be derived from the wallclock instead of the timestamp provided by the capture device. This lets you work around devices that provide unreliable timestamps. Very slay of you to fix their mess ๐ธ
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:
(and we're picking that one up in the next part, hold that thought ๐ฆ)
$ ffmpeg -f dshow -video_device_number 1 -i video="Camera"โ picks the second video device that literally goes by the name Camera, because the index here is1(it's zero-based, bestie ๐ ).- Open video device Camera and audio device Microphone:
$ ffmpeg -f dshow -i video="Camera":audio="Microphone"
- Print the list of supported options in selected device and exit โ like a little menu peek, then it dips out:
$ ffmpeg -list_options true -f dshow -i video="Camera"
- Specify pin names to capture by name or alternative name, specify alternative device name โ yes this line is as long as it looks, do not fear it:
$ 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"
- Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup โ crossbars are giving main-character energy ngl:
$ 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"
๐ fbdev ๐
The Linux framebuffer input device. Say hi ๐
So the Linux framebuffer is this graphic hardwareโindependent abstraction layer for showing graphics on a computer monitor โ typically on the console. You reach it through a file device node, and that node is usually /dev/fb0 ๐.
Want the deep lore? Go read the file Documentation/fb/framebuffer.txt that ships inside the Linux source tree. Also peep <http://linux-fbdev.sourceforge.net/> and fbset(1).
To record from the framebuffer device /dev/fb0 with ffmpeg:
ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
And you can absolutely snag a single screenshot image with this one:
ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
Options
framerateโ sets the frame rate. Default is25. slay.
๐ฅ๏ธ gdigrab ๐ฅ๏ธ
The Win32 GDIโbased screen capture device โ Windows girlies rise ๐โจ
This device lets you capture a region of the display on Windows.
Amongst the options for the input filenames are such elements as:
desktop
or
title=<window_title>
or
hwnd=<window_hwnd>
The first one captures the entire desktop, or a fixed region of the desktop. The second and third instead capture the contents of a single window, no matter where that window is sitting on your screen. Iconic, honestly.
For example, to grab the entire 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 tells it whether to draw the mouse pointer. Use the value0to not draw the pointer. Default value is1. (Yes, cursor can stay, she's part of the aesthetic ๐ฑ๏ธ)framerateโ sets the grabbing frame rate. Default value isntsc, which corresponds to a frame rate of30000/1001. periodt.show_regionโ shows the grabbed region on screen.
If show_region is specified with 1, then the grabbing region gets 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 ๐
Heads up bestie: show_region is incompatible with grabbing the contents of a single window.
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. The 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 note note: the offset calculation is from the top left corner of the primary monitor on Windows. If you have 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. negative girlie ๐
offset_yโ when capturing a region withvideo_size, this sets the distance from the top edge of the screen or desktop.
Same deal: offset calculation starts at the top left corner of the primary monitor on Windows. Monitor sitting above your primary? Negative offset_y value, go go go โฌ๏ธ
๐ฅ iec61883 ๐ฅ
FireWire DV/HDV input device using libiec61883. Retro tech but make it cute ๐
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 was removed. rip old stack ๐
Specify the FireWire port to be used as input file, or auto to choose the first port connected.
Options
dvtypeโ overrides autodetection of DV/HDV. This should only be used if auto detection doesn't work, or if usage of a different device type should be prohibited.
๐จ Treating a DV device as HDV (or the other way around) will not work and results in undefined behavior. The valuesauto,dvandhdvare supported.
dvbufferโ sets the maximum size of buffer for incoming data, in frames. For DV this is an exact value. For HDV it is not frame exact, since HDV doesn't have a fixed frame size. iykyk.dvguidโ selects the capture device by specifying its GUID. Capturing will only be performed from the specified device and fails if no device with the given GUID is found. This is useful to select the input if 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 ๐ง
The JACK input device. Audio besties, this one's for you ๐ซถ
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 name client_name:input_N, where client_name is the name provided by the application, and N is a number which identifies the channel. Each writable client will send 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
For more information read: <http://jackaudio.org/>
Options
channelsโ sets the number of channels. Default is2. stereo supremacy ๐
๐ kmsgrab ๐
The KMS video input device. Certification: advanced. Vibes: immaculate.
Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a DRM object that can be passed to other hardware functions.
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. no cap, that's literally what the page says ๐ญ
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 it 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.
Important: 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 to 30.
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 ๐
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
- To capture 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
๐ฆ lavfi ๐ฆ
The Libavfilter input virtual device. She's the filtergraph girlie and she's everything โจ
This input device reads data from the open output pads of a libavfilter filtergraph.
For each filtergraph open output, the input device creates a corresponding stream which is mapped to the generated output. The filtergraph is specified through the option graph.
Options
graph
Okay bestie, this one's the big one ๐ โ it specifies the filtergraph to use as input.
Every video open output has got 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 gets auto-assigned the "out0" label (she's the main character, she doesn't need to introduce herself ๐
), but all the others? Yeah, those need to be specified explicitly. No shortcuts.
You can tack the suffix "+subcc" onto the output label to create an extra stream with the closed captions packets attached to that output โ this is experimental, and for now it's only for EIA-608 / CEA-708. The subcc streams get created after all the normal streams, in the order of the corresponding stream. Example time, because honestly this is so much clearer with numbers: 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. See? Math. Iconic. ๐ง
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 ๐. The syntax of the filtergraph is literally the same as the one specified by the graph option. Same vibes, different delivery method.
dumpgraph
Dump graph to stderr. That's it, that's the whole thing ๐ซถ.
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 for specifying the graph description, and omit the
"out0"label:
ffplay -f lavfi color=c=pink
- Create three different video test filtered sources and play them:
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 it 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
libcdio
Audio-CD input device based on libcdio ๐ฟ.
To enable this input device during configuration you need libcdio installed on your system. It requires the configure option --enable-libcdio.
This device allows playing and grabbing from an Audio-CD. So like, ripping. But make it โจopen sourceโจ.
For example, to copy with ffmpeg the entire Audio-CD in /dev/sr0, you may run the command:
ffmpeg -f libcdio -i /dev/sr0 cd.wav
Options
speedโ Set drive reading speed. Default value is0.
The speed is specified in CD-ROM speed units. The speed is set through the libcdio cdio_cddap_speed_set function. Heads up ๐ซถ: on many CD-ROM drives, specifying a value that's too large will just result in using the fastest speed. She'll do what she wants.
paranoia_modeโ Set paranoia recovery mode flags. It accepts one of the following values:disableverifyoverlapneverskipfull
Default value is disable.
For more information about the available recovery modes, consult the paranoia project documentation.
libdc1394
IIDC1394 input device, based on libdc1394 and libraw1394 ๐ฅ.
Requires the configure option --enable-libdc1394.
Options
framerateโ Set the frame rate. Default is"ntsc", corresponding to a frame rate of30000/1001. Very specific of her, honestly.pixel_formatโ Select the pixel format. Default is"uyvy422".video_sizeโ Set the video size given as a string such as"640x480"or"hd720". Default is"qvga".
openal
The OpenAL input device provides audio capture on all systems with a working OpenAL 1.1 implementation ๐ง.
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 be provided 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 the --extra-cflags and --extra-ldflags for allowing the build system to locate the OpenAL headers and libraries. Annoying? Lowkey yes. Necessary? Also yes ๐ญ.
An incomplete list of OpenAL implementations follows:
- Creative โ The official Windows implementation, providing hardware acceleration with supported devices and software fallback. See <http://openal.org/>.
- OpenAL Soft โ 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 allows one to capture from an audio input device handled through OpenAL.
You need to specify the name of the device to capture in the provided filename. If the empty string is provided, the device will automatically select the default device. You can get the list of the supported devices by using the option list_devices.
Options
channelsโ Set the number of channels in the captured audio. Only the values1(monaural) and2(stereo) are currently supported. Defaults to2.sample_sizeโ Set the sample size (in bits) of the captured audio. Only the values8and16are currently supported. Defaults to16.sample_rateโ Set the sample rate (in Hz) of the captured audio. Defaults to44.1k.list_devicesโ If set to true, print a list of devices and exit. Defaults tofalse.
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 filename โ yes, on purpose ๐):
$ ffmpeg -f openal -i '' out.ogg
Capture from two devices simultaneously, writing to two different files, 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. She's trying her best ๐
oss
Open Sound System input device ๐.
The filename to provide to the input device is the device node representing the OSS input device, and is usually set to /dev/dsp.
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_rateโ Set the sample rate in Hz. Default is48000.channelsโ Set the number of channels. Default is2.
pulse
PulseAudio input device ๐ฆ.
To enable this output device you need to configure FFmpeg with --enable-libpulse.
The filename to 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.
More information about PulseAudio can be found on <http://www.pulseaudio.org>.
Options
serverโ Connect to a specific PulseAudio server, specified by an IP address. Default server is used when not provided.nameโ Specify the application name PulseAudio will use when showing active clients; by default it is the"LIBAVFORMAT_IDENT"string.stream_nameโ Specify the stream name PulseAudio will use when showing active streams; by default it is"record".sample_rateโ Specify the samplerate in Hz; by default48kHzis used.channelsโ Specify the channels in use; by default2(stereo) is set.frame_sizeโ This option does nothing and is deprecated. Rip to her, she's a ghost ๐ปfragment_sizeโ Specify the size in bytes of the minimal buffering fragment in PulseAudio; it will affect the audio latency. By default it is set to50 msamount of data.wallclockโ Set the initial PTS using the current time. Default is1.
Examples
Record a stream from default device:
ffmpeg -f pulse -i default /tmp/pulse.wav
sndio
sndio input device ๐.
To enable this input device during configuration you need libsndio installed on your system.
The filename to provide to the input device is the device node representing the sndio input device, and is usually set to /dev/audio0.
For example to grab from /dev/audio0 using ffmpeg use the command:
ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
Options
sample_rateโ Set the sample rate in Hz. Default is48000.channelsโ Set the number of channels. Default is2.
video4linux2, v4l2
Video4Linux2 input video device ๐น.
"v4l2" can be used as alias for "video4linux2". Same girl, shorter name ๐
.
If FFmpeg is built with v4l-utils support (by using the --enable-libv4l2 configure option), it is possible to use it with the -use_libv4l2 input device option.
The name of the device to grab is a file device node; usually Linux systems tend to automatically create such nodes when the device (e.g. an USB webcam) is plugged into the system, and has a name of the kind /dev/videoN, where N is a number associated to the device.
Video4Linux2 devices usually support a limited set of widthx*height* sizes and frame rates. You can check which are supported using -list_formats all for Video4Linux2 devices. Some devices, like TV cards, support one or more standards. It is 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. Clock lore fr fr โญ
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, leave 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
Okay, back in the v4l2 option buffet โ grab a plate, bestie, because these knobs are lowkey essential:
standardโ Sets the standard. It has to be the name of a standard that's actually supported. Wanna see the roster? Use thelist_standardsoption. โจchannelโ Sets the input channel number. Default is-1, which means it uses the previously selected channel. No cap.video_sizeโ Sets the video frame size. The argument must be a string in the formWIDTHxHEIGHTor a valid size abbreviation. ๐pixel_formatโ Selects the pixel format (only valid for raw video input). ๐input_formatโ Sets the preferred pixel format (for raw video) or a codec name. This option lets you select the input format when several are available. ๐ฆframerateโ Sets the preferred video frame rate. ๐ธlist_formatsโ Lists available formats (supported pixel formats, codecs, and frame sizes) and exits. Available values are:allโ Show all available (compressed and non-compressed) formats.rawโ Show only raw video (non-compressed) formats.compressedโ Show only compressed formats.
list_standardsโ Lists supported standards and exits. Available values are:allโ Show all supported standards.
timestamps,tsโ Sets the type of timestamps for grabbed frames. Available values are:defaultโ Use timestamps from the kernel.absโ Use absolute timestamps (wall clock).mono2absโ Force conversion from monotonic to absolute timestamps.
Default value is default.
use_libv4l2โ Use libv4l2 (v4l-utils) conversion functions. Default is0.
๐ฅ vfwcap ๐ฅ
VfW (Video for Windows) capture input device. The filename passed as input is the capture driver number, ranging from 0 to 9. You may use list as filename to print a list of drivers. Any other filename will be interpreted as device number 0. ๐ซถ
โจ Options โจ
video_sizeโ Set the video frame size.framerateโ Set the grabbing frame rate. Default value isntsc, corresponding to a frame rate of30000/1001. ๐ฅ
๐ฆ x11grab ๐ฆ
X11 video input device. To enable this input device during configuration you need libxcb installed on your system. It will be automatically detected during configuration. This device allows one to capture a region of an X11 display. periodt.
The filename passed as input has the syntax:
[<hostname>]:<display_number>.<screen_number>[+<x_offset>,<y_offset>]
hostname:display_number.screen_number specifies the X11 display name of the screen to grab from. hostname can be omitted, and defaults to localhost. The environment variable DISPLAY contains the default display name.
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. ๐
Check the X11 documentation (e.g. man X) for more detailed information. Use the xdpyinfo program for getting basic information about the properties of your X11 display (e.g. grep for "name" or "dimensions"). ๐
For example to grab from :0.0 using ffmpeg:
ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
Grab at position 10,20:
ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
๐ Options ๐
select_regionโ Specify whether to select the grabbing area graphically using the pointer. 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. ๐draw_mouseโ Specify whether to draw the mouse pointer. A value of0specifies not to draw the pointer. Default value is1. ๐follow_mouseโ Make the grabbed area follow the mouse. The argument can becenteredor a number of pixelsPIXELS.
When it is specified with centered, the grabbing region follows the mouse pointer and keeps the pointer at the center of the region; otherwise, the region follows only when the mouse pointer reaches within PIXELS (greater than zero) to 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 Set the grabbing frame rate. Default value isntsc, corresponding to a frame rate of30000/1001. ๐show_regionโ Show the grabbed region on screen. Ifshow_regionis specified with1, then the grabbing region will be indicated on screen. With this option, it is easy to know what is being grabbed if only a portion of the screen is grabbed. โญregion_borderโ Set the region border thickness if-show_region 1is used. Range is1to128and default is3(XCB-based x11grab only).
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. 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 options -tree and -root.
If the window is later enlarged, the new area is not recorded. Video ends when the window is closed, unmapped (i.e., iconified) or shrunk beyond the video size (which defaults to the initial window size).
This option disables options follow_mouse and select_region. ๐
video_sizeโ Set the video frame size. Default is the full desktop or window. ๐งgrab_x,grab_yโ Set the grabbing region coordinates. They are expressed as 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 is0. ๐
๐ RESAMPLER OPTIONS ๐
Okay bestie, so the audio resampler has a whole little universe of named options and we're gonna go through every single one, no skips, no cap โจ
You can set these a bunch of ways, and literally all of them count:
- by specifying
-option valuein the FFmpeg tools option=valuefor thearesamplefilter- by setting the value explicitly in the
SwrContextoptions - or using the
libavutil/opt.hAPI for programmatic use (iykyk ๐ง)
uchl,used_chlayoutโ sets the used input channel layout. Default is unset. Heads up: this one is only used for special remapping, so it's giving niche-but-iconic ๐isr,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 specifies the input sample format. It defaults tonone.osf,out_sample_fmtโ specifies the output sample format. Defaults tonone.tsf,internal_sample_fmtโ sets the internal sample format. Default value isnone. When you don't set it explicitly, it just picks one for you automatically โ main character energy, it handles itself ๐ichl,in_chlayoutandochl,out_chlayoutโ set the input/output channel layout. For the exact syntax you gotta check the Channel Layout section in theffmpeg-utils(1)manual, okay? Don't guess, go read it ๐clev,center_mix_levelโ sets the center mix level. It's a value in deciBel, and it must be in the interval[-32,32].slev,surround_mix_levelโ sets the surround mix level. Also in deciBel, also has to be in the interval[-32,32].lfe_mix_levelโ sets the LFE mix into non-LFE level. It kicks in when you've got an LFE input but no LFE output. Value in deciBel, and yeah, interval[-32,32].rmvol,rematrix_volumeโ sets rematrix volume. Default value is1.0.rematrix_maxvalโ sets the maximum output value for rematrixing. This is your lil tug-of-war: preventing clipping vs. preventing volume reduction. A value of1.0prevents clipping. Choose wisely bestie ๐ธflags,swr_flagsโ sets flags used by the converter. Default value is0.
It supports this individual flag:
resโ force resampling. Like the name says, it forces resampling to be used even when the input and output sample rates match.
dither_scaleโ sets the dither scale. Default value is1.dither_methodโ sets the dither method. Default value is0.
Supported values, going down the list:
rectangularโ select rectangular dithertriangularโ select triangular dithertriangular_hpโ select triangular dither with high passlipshitzโ select Lipshitz noise shaping dither.shibataโ select Shibata noise shaping dither.low_shibataโ select low Shibata noise shaping dither.high_shibataโ select high Shibata noise shaping dither.f_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 sets the resampling engine. Default value isswr.
Supported values:
swrโ select the native SW Resampler; filter optionsprecisionandchebyare not applicable in this case.soxrโ select the SoX Resampler (where available);compensation, and filter optionsfilter_size,phase_shift,exact_rational,filter_type&kaiser_beta, are not applicable in this case.
filter_sizeโ forswronly, sets the resampling filter size, default value is32.phase_shiftโ forswronly, sets resampling phase shift, default value is10, and it must be in the interval[0,30].linear_interpโ use linear interpolation when enabled (and it's enabled by default). Disable it if you'd rather preserve speed instead of quality whenexact_rationalfails. Trade-offs, bestie ๐exact_rationalโ forswronly. When enabled, it tries to use an exactphase_countbased on the input and output sample rate. BUT โ if that ends up larger than1 << phase_shift, then thephase_countbecomes1 << phase_shiftas a fallback. Default is enabled.cutoffโ sets cutoff frequency ratio (swr: 6dB point;soxr: 0dB point). Must be a float value between0and1. Default value is0.97withswr, and0.91withsoxrโ and that soxr one, with a sample-rate of44100, preserves the entire audio band to 20kHz. Obsessed with her attention to detail ๐precisionโ forsoxronly, the precision in bits to which the resampled signal will be 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'. Glow-up unlocked โจchebyโ forsoxronly, selects passband rolloff none (Chebyshev) & higher-precision approximation for 'irrational' ratios. Default value is0.asyncโ forswronly. It's a simple 1-parameter audio sync to timestamps, doing it via 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 gets applied to make the samples match the audio timestamps.first_ptsโ forswronly, assumes the first pts should be this value. The time unit is1 / sample rate. This lets you do 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 is done. For 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 due to encoder delay. Very "let me fix this for you" of it ๐ซถmin_compโ forswronly, sets the minimum difference between timestamps and audio data (in seconds) needed to trigger stretching/squeezing/filling or trimming of the data so it matches the timestamps. The default is that stretching/squeezing/filling and trimming is disabled (min_comp=FLT_MAX).min_hard_compโ forswronly, sets the minimum difference between timestamps and audio data (in seconds) to trigger adding/dropping samples so it matches the timestamps. This option is basically a threshold that picks between hard (trim/fill) and soft (squeeze/stretch) compensation. Note: all compensation is disabled by default throughmin_comp. The default here is0.1.comp_durationโ forswronly, sets the duration (in seconds) over which data is stretched/squeezed to make it match the timestamps. Must be a non-negative double float value, default value is1.0.max_soft_compโ forswronly, sets the maximum factor by which data is stretched/squeezed to make it match the timestamps. Must be a non-negative double float value, default value is0.matrix_encodingโ selects matrixed stereo encoding.
It accepts the following values:
noneโ select nonedolbyโ select Dolbydpliiโ select Dolby Pro Logic II
Default value is none.
filter_typeโ forswronly, selects the resampling filter type. Just so you know, 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, sets the Kaiser window beta value. Must be a double float value in the interval[2,16], default value is9.output_sample_bitsโ forswronly, sets 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. Frugal queen ๐
โจ SCALER OPTIONS โจ
okay so the video scaler has its own whole lil set of named options and we're gonna go through every single one, no skipping ๐
You can set these by doing -option value in the FFmpeg tools, with a couple of API-only exceptions flagged down below (iykyk). And if you're doing the programmatic thing, you can set them explicitly in the SwsContext options or through the libavutil/opt.h API. ๐ซถ
sws_flags
Sets the scaler flags. This is ALSO how you pick the scaling algorithm, bestie โ and you should only select a single algorithm. Default value is bicubic.
It accepts the following values:
fast_bilinearโ picks the fast bilinear scaling algorithm.bilinearโ picks the bilinear scaling algorithm.bicubicโ picks the bicubic scaling algorithm.experimentalโ picks the experimental scaling algorithm ๐neighborโ picks the nearest neighbor rescaling algorithm.areaโ picks the averaging area rescaling algorithm.bicublinโ bicubic for the luma component, bilinear for the chroma components. two vibes at once โจgaussโ picks the Gaussian rescaling algorithm.sincโ picks the sinc rescaling algorithm.lanczosโ picks the Lanczos rescaling algorithm. The default width (alpha) is3and can be changed by settingparam0.splineโ picks the natural bicubic spline rescaling algorithm.print_infoโ enables printing/debug logging.accurate_rndโ enables accurate rounding.full_chroma_intโ enables full chroma interpolation.full_chroma_inpโ selects full chroma input.bitexactโ enables bitexact output.unstableโ allows the use of experimental new code. May subtly affect the output or even produce wrong results. For testing only, fr fr ๐
srcw (API only)
Sets the source width.
srch (API only)
Sets the source height.
dstw (API only)
Sets the destination width.
dsth (API only)
Sets the destination height.
src_format (API only)
Sets the source pixel format (must be expressed as an integer).
dst_format (API only)
Sets the destination pixel format (must be expressed as an integer).
src_range (boolean)
If the value is set to 1, it means the source is full range. Default value is 0, which means the source is limited range.
dst_range (boolean)
If the value is set to 1, full range gets enabled for the destination. Default value is 0, which enables limited range.
gamma (boolean)
If the value is set to 1, gamma correct scaling gets enabled. Default value is 0.
param0, param1
Set scaling algorithm parameters. The values you specify are specific to some scaling algorithms and just ignored by others, nbd. The specified values are floating point number values.
sws_dither
Sets the dithering algorithm. Accepts one of the following values. Default value is auto.
autoโ automatic choice โจnoneโ 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, if you're into that ๐ )
alphablend
Sets 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 checkerboardnoneโ no blending
๐ฆ FILTERING INTRODUCTION ๐ฆ
So filtering in FFmpeg is enabled through the libavfilter library. That's the whole vibe check. ๐
In libavfilter, a filter can have multiple inputs AND multiple outputs โ main character energy, honestly. 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. literally so iconic ๐ญ
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. In the example, the split filter generates two outputs that are associated to the labels [main] and [tmp].
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. ๐
There exist so-called source filters that do not have an audio/video input, and sink filters that will not have audio/video output. slay, they're special like that.
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. fancy ๐
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. obsessed.
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. ngl this part trips people up, so like, double check it bestie ๐ซถ
๐ธ FILTERGRAPH DESCRIPTION ๐ธ
okay bestie so a filtergraph is literally a directed graph of connected filters โ yes, an actual graph, we're doing graph theory in our media player, it's giving CS major era ๐
It can contain cycles, and there can be multiple links between a pair of filters. And likeโฆ each link has one input pad on one side connecting it to one filter from which it takes its input, and one output pad on the other side connecting it to one filter accepting its output. Pads are the little handshake points, iykyk ๐ค
Each filter in a filtergraph is an instance of a filter class registered in the application, which defines the features and the number of input and output pads of the filter.
A filter with no input pads is called a "source", and a filter with no output pads is called a "sink". Sources give, sinks take, main character energy on both ends โจ
๐ Filtergraph syntax ๐
A filtergraph has a textual representation, which is recognized by the -filter/-vf/-af and -filter_complex options in ffmpeg and -vf/-af in ffplay, and by the avfilter_graph_parse_ptr() function defined in libavfilter/avfilter.h.
So here's the tea on how it's built up, layer by layer ๐ง
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 has to be the name of one of the filter classes registered in the program optionally followed by @id. The name of the filter class is optionally followed by a string =arguments.
arguments is a string which contains the parameters used to initialize the filter instance. It may have 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 -- type, start_frame and nb_frames. Then the parameter listin:0:30means that the valueinis assigned to the optiontype,0tostart_frameand30tonb_frames. - 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.
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 be 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.
The name and arguments of the filter are optionally preceded and followed by a list of link labels. A link label allows one to 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. it's literally matchmaking for pads 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.
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. defaults slay ๐ซถ
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 orphan pads allowed, we don't do that here ๐ค
Leading and trailing whitespaces (space, tabs, or line feeds) separating tokens in the filtergraph specification are ignored. This means that the filtergraph can be expressed using empty lines and spaces to improve readability. aesthetic formatting is valid formatting bestie โจ
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. It is possible to specify swscale flags for those automatically inserted scalers by prepending sws_flags=flags; to the filtergraph description.
Here is a BNF description of the filtergraph syntax โ iconic, legendary, no notes:
<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>]
๐ฆ Notes on filtergraph escaping ๐ฆ
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. ๐ญ yes it's that deep
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). ๐ซ
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. ๐ real
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. way easier, trust ๐
โญ TIMELINE EDITING โญ
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. on/off era, we love a boolean moment ๐ฅ
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 ๏ธw,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. live editing, we love to see it โจ
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, the list is right there bestie ๐
๐ CHANGING OPTIONS AT RUNTIME WITH A COMMAND ๐
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. ๐
So like, 'T' = "this one's live, you can poke it while it's running." periodt ๐
โจ OPTIONS FOR FILTERS WITH SEVERAL INPUTS โจ
Okay bestie, some filters with several inputs support a common set of options. Important: these options can only be set by name, not with the short notation. No shortcuts here, iykyk ๐
eof_actionโ the action to take when EOF is encountered on the secondary input. It accepts one of these values:repeatโ repeat the last frame (the default).endallโ end both streams.passโ pass the main input through.
shortestโ if set to1, force the output to terminate when the shortest input terminates. Default value is0.repeatlastโ if set to1, force the filter to extend the last frame of secondary streams until the end of the primary stream. A value of0disables this behavior. Default value is1.ts_sync_modeโ how strictly to sync streams based on secondary input timestamps. It accepts one of these values:defaultโ frame from secondary input with the nearest lower or equal timestamp to the primary input frame.nearestโ frame from secondary input with the absolute nearest timestamp to the primary input frame.
๐ง AUDIO FILTERS ๐ง
When you configure your FFmpeg build, you can disable any of the existing filters using --disable-filters. The configure output will show the audio filters included in your build.
Below is a description of the currently available audio filters. Letโs gooo ๐
๐ aap
Apply Affine Projection algorithm to the first audio stream using the second audio stream.
This adaptive filter is used to estimate unknown audio based on multiple input audio samples. Affine projection algorithm can make trade-offs between computation complexity with convergence speed. Iconic behavior fr ๐
The filter accepts the following options. โจ
orderโ set the filter order.projectionโ set the projection order.muโ set the filter mu.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.
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.
๐๏ธ 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. Itโs done to get the highest attention of a listener, โfattenโ the sound and bring more โpowerโ to the track. If a signal is compressed too much it may sound dull or โdeadโ afterwards or it may start to โpumpโ (which could be a powerful effect but can also destroy a track completely). 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.
Compression is done by detecting the volume above a chosen level โthresholdโ and dividing it by the factor set with โratioโ. 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 โAttackโ and โReleaseโ. โattackโ determines how long the signal has to rise above the threshold before any reduction will occur and โreleaseโ 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. The overall reduction of the signal can be made up afterwards with the โmakeupโ setting. So compressing the peaks of a signal about 6dB and raising the makeup to this level results in a signal twice as loud than the source. To gain a softer entry in the compression the โkneeโ flattens the hard edge at the threshold in the range of the chosen decibels.
The filter accepts the following options:
level_inโ set input gain. Default is1. Range is between0.015625and64.modeโ set mode of compressor operation. Can beupwardordownward. Default isdownward.thresholdโ if a signal of stream rises above this level it will affect the gain reduction. By default it is0.125. Range is between0.00097563and1.ratioโ set a ratio by which the signal is reduced.1:2means that if the level rose 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. Default is2.82843. Range is between1and8.linkโ choose if theaveragelevel between all channels of input stream or the louder (maximum) channel of input stream affects the reduction. Default isaverage.detectionโ should the exact signal be taken in case ofpeakor an RMS one in case ofrms. Default isrmswhich is mostly smoother.mixโ how much to use compressed signal in output. Default is1. Range is between0and1.
๐ Commands
This filter supports all of the above options as commands. Slay ๐
๐ธ acontrast
Simple audio dynamic range compression/expansion filter.
The filter accepts the following options:
contrastโ set contrast. Default is33. Allowed range is between0and100.
๐ acopy
Copy the input audio source unchanged to the output. This is mainly useful for testing purposes. Lowkey the simplest icon here ๐ซถ
๐ฆ acrossfade
Apply cross fade from one input audio stream to another input audio stream. The cross fade is applied for specified duration near the end of first stream.
The filter accepts the following 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 theconcatfilter. Default is2.nb_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 is44100.duration,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_samples.overlap,oโ should first stream end overlap with second stream start. Default is enabled.curve1โ set curve for cross fade transition for first stream.curve2โ set curve for cross fade transition for second stream.
For description of available curve types see afade filter description.
โจ 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
๐ acrossover
Split audio stream into several bands.
This filter splits audio stream into two or more frequency ranges. Summing all streams back will give flat output.
The filter accepts the following options:
splitโ set split frequencies. Those must be positive and increasing.orderโ 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 octave.4thโ 24 dB per octave.6thโ 36 dB per octave.8thโ 48 dB per octave.10thโ 60 dB per octave.12thโ 72 dB per octave.14thโ 84 dB per octave.16thโ 96 dB per octave.18thโ 108 dB per octave.20thโ 120 dB per octave.
Default is 4th.
levelโ set input gain level. Allowed range is from0to1. Default value is1.gainsโ set output gain for each band. Default value is1for all bands.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.
Default value is auto.
๐ Examples
- Split input audio stream into two bands (low and high) with split frequency of 1500 Hz, each band will be in 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 additional middle band (frequencies between 1500 and 8000):
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
๐ฅ acrusher
Reduce audio bit resolution. ๐
okay so this filter is a bit crusher with enhanced functionality โ and itโs genuinely iconic, no cap. A bit crusher is used to audibly reduce the number of bits an audio signal is sampled with. The important part: this doesnโt change the bit depth at all, it just produces the effect. Material reduced in bit depth sounds more harsh and โdigital.โ 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 half and the upper half of the signal. And an Anti-Aliasing setting can produce โsofterโ crushing sounds. ๐
Another feature of this filter is the logarithmic mode. This setting switches from linear distances between bits to logarithmic ones. The result is a much more โnaturalโ sounding crusher which doesnโt 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. โจ
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.
๐ Commands ๐
This filter supports the all above options as commands.
๐ acue ๐
Delay audio filtering until a given wallclock timestamp. See the cue filter. Thatโs the whole vibe โ very โwait for itโ behavior. ๐ซถ
๐ฆ adeclick ๐ฆ
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 size of 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 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 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 be also 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".
๐ธ adeclip ๐ธ
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 size of 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".
๐ adecorrelate ๐
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.
โญ adelay โญ
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 number of given delays is smaller than number of channels all remaining channels will not be delayed. If you want to delay exact number of samples, append'S'to number. If you want instead to delay in seconds, append's'to number.allโ Use last set delay for all remaining channels. By default is disabled. This option if enabled changes how option"delays"is interpreted.
โจ Examples โจ
- Delay first channel by 1.5 seconds, the third channel by 0.5 seconds and leave the second channel (and any other channels that may be present) unchanged.
adelay=1500|0|500
- Delay second channel by 500 samples, the third channel by 700 samples 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
๐ง adenorm ๐ง
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".
๐ซ Commands ๐ซ
This filter supports the all above options as commands.
๐ aderivative, aintegral ๐
Compute derivative/integral of audio stream. Applying both filters one after another produces original audio. Itโs giving โundo buttonโ energy, honestly. ๐ญ
๐ฅ adrc ๐ฅ
Apply spectral dynamic range controller filter to input audio stream.
A description of the accepted options follows.
transferโ Set the transfer expression.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".
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.
๐ Commands ๐
This filter supports the all above options as commands.
๐ Examples ๐
- Apply spectral compression to all frequencies with threshold of -50 dB and 1:6 ratio:
adrc=transfer='if(gt(p,-50),-50+(p-(-50))/6,p)':attack=50:release=100
- Similar to above but with 1:2 ratio 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 -85 dB 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 -10 dB and 1:2 ratio:
adrc=transfer='if(lt(p,-10),-10+(p-(-10))*2,p)':attack=50:release=100
- Apply limiter to max -60 dB to all frequencies, with attack of 2 ms and release of 10 ms:
adrc=transfer='min(p,-60)':attack=2:release=10
๐ฆ adynamicequalizer ๐ฆ
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.
Okay bestie, back into the option list โ these are the detection/threshold modes for this filter:
cutbelowโ Cut frequencies below detection threshold.cutaboveโ Cut frequencies above detection threshold.boostbelowโ Boost frequencies below detection threshold.boostaboveโ Boost frequencies above detection threshold.
The default mode is cutbelow.
dftypeโ Set the type of detection filter. It can be one of the following:bandpasslowpasshighpasspeak
The default type is bandpass.
tftypeโ Set the type of target filter. It can be one of the following:belllowshelfhighshelf
The default type is bell.
autoโ Automatically gather threshold from the detection filter. By default this is disabled. This option is useful for detecting the threshold in a certain time frame of the input audio stream โ in that case the option value is changed at runtime. Available values are:disabledโ Disable using automatically gathered threshold value.offโ Stop picking threshold value.onโ Start picking threshold value.adaptiveโ Adaptively pick threshold value, by calculating sliding window entropy.
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.
๐ฌ Commands
This filter supports all the above options as commands. Slay, runtime tweaking unlocked. โจ
๐ซง adynamicsmooth
Apply dynamic smoothing to the input audio stream. Here's what you can tweak:
sensitivityโ Set the amount of sensitivity to frequency fluctations. Default is2. Allowed range is from0to1e+06.basefreqโ Set a base frequency for smoothing. Default value is22050. Allowed range is from2to1e+06.
๐ฌ Commands
This filter supports all the above options as commands. ๐ซถ
๐ aecho
Apply echoing to the input audio.
Echoes are reflected sound, and they can occur naturally amongst mountains (and sometimes large buildings) when you're talking or shouting. Digital echo effects emulate this behaviour and are often used to help fill out the sound of a single instrument or vocal. 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 have different delays and decays. Iconic behaviour, honestly.
Here are the accepted parameters:
in_gainโ Set input gain of the reflected signal. Default is0.6.out_gainโ Set output gain of the reflected signal. Default is0.3.delaysโ Set the list of time intervals in milliseconds between the original signal and reflections, separated by|. Allowed range for each delay is(0 - 90000.0]. Default is1000.decaysโ Set the list of loudness of reflected signals, separated by|. Allowed range for each decay is(0 - 1.0]. Default is0.5.
๐ 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:
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:
aecho=0.8:0.9:1000|1800:0.3|0.25
๐๏ธ aemphasis
Audio emphasis filter creates or restores material directly taken from LPs or emphased CDs with different filter curves. E.g. to store music on vinyl, the signal has to be altered by a filter first to even out the disadvantages of this recording medium. Once the material is played back, the inverse filter has to be applied to restore the distortion of the frequency response. Literally giving restoration main character energy. ๐
The filter accepts the following options:
level_inโ Set input gain.level_outโ Set output gain.modeโ Set filter mode. For restoring material usereproductionmode, otherwise useproductionmode. Default isreproductionmode.typeโ Set filter type. Selects 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).
๐ฌ Commands
This filter supports all the above options as commands. ๐
๐งฎ aeval
Modify an audio signal according to the specified expressions.
This filter accepts one or more expressions (one for each channel), which are evaluated and used to modify a corresponding audio signal.
It accepts the following parameters:
exprsโ Set 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.channel_layout,cโ Set 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 expressionnโ number of the evaluated sample, starting from0sโ sample ratetโ time of the evaluated sample expressed in secondsnb_in_channels,nb_out_channelsโ input and output number of channelsval(CH)โ the value of input channel with number CH
Note: this filter is slow. For faster processing you should use a dedicated filter. ๐
๐ Examples
- Half volume:
aeval=val(ch)/2:c=same
- Invert phase of the second channel:
aeval=val(0)|-val(1)
โจ aexciter
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 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, to create a more "crisp" or "brilliant" sound. It's giving sparkle but make it DSP. ๐ฅ
The filter accepts the following options:
level_inโ Set input level prior processing of signal. Allowed range is from0to64. Default value is1.level_outโ Set output level after processing of signal. Allowed range is from0to64. Default value is1.amountโ Set the amount of harmonics added to original signal. Allowed range is from0to64. Default is1.driveโ Set the amount of newly created harmonics. Allowed range is from0.1to10. Default is8.5.blendโ Set the octave of newly created harmonics. Allowed range is from-10to10. Default is0.freqโ Set the lower frequency limit of producing harmonics in Hz. Allowed range is from2000to12000Hz. Default is7500Hz.ceilโ Set the upper frequency limit of producing harmonics. Allowed range is from9999to20000Hz. If value is lower than10000Hz no limit is applied.listenโ Mute the original signal and output only added harmonics. By default is disabled.
๐ฌ Commands
This filter supports all the above options as commands. ๐
๐ฌ afade
Apply fade-in/out effect to input audio.
Here's what the accepted parameters do:
type,tโ Specify the effect type. Can be eitherinfor fade-in, oroutfor a fade-out effect. Default isin.start_sample,ssโ Specify the number of the start sample for starting to apply the fade effect. Default is0.nb_samples,nsโ Specify 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; at the end of the fade-out transition the output audio will be silence. Default is44100.start_time,stโ Specify the start time of the fade effect. Default is0. The value must be specified as a time duration; see the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. If set, this option is used instead ofstart_sample.duration,dโ Specify the duration of the fade effect. See the Time duration section in theffmpeg-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; 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 Set curve for fade transition. It accepts the following values: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 Set the initial gain for fade-in or final gain for fade-out. Default value is0.0.unityโ Set the initial gain for fade-out or final gain for fade-in. Default value is1.0.
๐ฌ Commands
This filter supports all the above options as commands. ๐ฆ
๐ Examples
- Fade in first 15 seconds of audio:
afade=t=in:ss=0:d=15
- Fade out last 25 seconds of a 900 seconds audio:
afade=t=out:st=875:d=25
๐ง afftdn
Denoise audio samples with FFT.
okay so here's the full rundown of every parameter this thing eats, no skips, no cap ๐
noise_reduction,nrโ sets the noise reduction in dB. allowed range is 0.01 to 97. default is 12 dB. โจnoise_floor,nfโ sets the noise floor in dB. allowed range is -80 to -20. default is -50 dB.noise_type,ntโ sets the noise type, bestie. 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. ๐
band_noise,bnโ sets a custom band noise profile for every one of 15 bands. bands are separated by' 'or'|'. iykyk ๐ซถresidual_floor,rfโ sets the residual floor in dB. allowed range is -80 to -20. default is -38 dB.track_noise,tnโ enables noise floor tracking. by default it's disabled. with this on, the noise floor gets adjusted automatically. literally hands-free ๐ฆtrack_residual,trโ enables residual tracking. by default it's disabled.output_mode,omโ sets the output mode. it accepts: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 like how fast it adapts gain adjustments per each frequency bin. value0enables instant adaptation, while higher values react much slower. allowed range is 0 to 1. default is 0.5. she's flexible ๐floor_offset,foโ sets the noise floor offset factor. this one adjusts the offset applied to the measured noise floor. heads up: it's only effective when noise floor tracking is enabled ๐ฅ. allowed range is -2.0 to 2.0. default is 1.0.noise_link,nlโ sets the noise link used for multichannel audio. accepts: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 0.2 to 5. default is 1.25.sample_noise,snโ toggles capturing and measurement of the noise profile from input audio. it accepts: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. super useful for reducing random music noise artefacts โจ. higher values increase the smoothing of gains. allowed range is 0 to 50. default is 0.
๐น๏ธ Commands
this filter supports some of the above mentioned options as commands. periodt ๐
๐ Examples
- reduce white noise by 10dB, and use a previously measured noise floor of -40dB:
afftdn=nr=10:nf=-40
- reduce white noise by 10dB, also set the initial noise floor to -80dB and enable automatic tracking of noise floor so the noise floor will gradually change during processing:
afftdn=nr=10:nf=-80:tn=1
- reduce noise by 20dB, using a noise floor of -40dB and using commands to take the noise profile of the first 0.4 seconds of input audio:
asendcmd=0.0 afftdn sn start,asendcmd=0.4 afftdn sn stop,afftdn=nr=20:nf=-40
๐๏ธ afftfilt
applies arbitrary expressions to samples in frequency domain. she's doing math in the frequency domain, main character energy fr fr ๐
โจ real
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.
๐ imag
sets the frequency domain imaginary expression for each separate channel, separated by '|'. default is "im".
each expression in real and imag can contain the following 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_size
sets the window size. allowed range is 16 to 131072. default is 4096.
win_func
sets the window function. it accepts:
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". so many windows, and honestly? each one ate ๐
overlap
sets the window overlap. if it's set to 1, the recommended overlap for the selected window function will be picked. default is 0.75.
๐ธ 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)"
๐ฆ afir
applies an arbitrary Finite Impulse Response filter. icon behavior honestly.
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. she contains multitudes ๐
heads up on how it works: 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 the same as the number of channels in the first stream. no cap.
it accepts the following 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 is 1, which means the whole IR is processed.gtypeโ this option is deprecated, and does nothing. ๐ literally a ghost.irnormโ set norm to be applied to IR coefficients before filtering. allowed range is -1 to 2. 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 is 1.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 is true.irgainโ set gain to be applied to IR coefficients before filtering. allowed range is 0 to 1. 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 is 30 seconds. allowed range is 0.1 to 60 seconds.responseโ this option is deprecated, and does nothing. ๐channelโ this option is deprecated, and does nothing. ๐sizeโ this option is deprecated, and does nothing. ๐rateโ this option is deprecated, and does nothing. ๐minpโ set minimal partition size used for convolution. default is 8192. allowed range is 1 to 65536. lower values decrease latency at the cost of higher CPU usage. trade-offs, always ๐ญmaxpโ set maximal partition size used for convolution. default is 8192. allowed range is 8 to 65536. lower values may increase CPU usage.nbirsโ set number of input impulse responses streams which will be switchable at runtime. allowed range is 1 to 32. default is 1.irโ set IR stream which will be used for convolution, starting from0, should always be lower than the value supplied by thenbirsoption. default is 0. this option can be changed at runtime via commands. slay ๐ฅprecisionโ set which precision to use when processing samples. it accepts: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". first one loads and prepares all IRs on initialization, second one once on first access of a specific IR. default is"init".
๐ Examples
- apply reverb to a stream using a 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, 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
irgainexplicitly set to the estimated value and withirnormdisabled:
"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"
โญ aformat
sets output format constraints for the input audio. the framework will negotiate the most appropriate format to minimize conversions. she negotiates. she compromises. she minimizes conversions ๐ซถ
it accepts the following parameters:
sample_fmts,fโ a|-separated list of the sample formats you're asking for โจsample_rates,rโ same deal, but for sample rates, also|-separatedchannel_layouts,clโ and again for channel layouts,|-separated bestie
Peep the Channel Layout section in the ffmpeg-utils(1) manual for the exact syntax you need here ๐
If you justโฆ don't pass a parameter at all? Then every value is fair game. No restrictions, no vibe check, all allowed ๐
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
afreqshift ๐
Applies a frequency shift to the input audio samples. Iconic little pitch-scoot, honestly.
The filter accepts these options:
shiftโ the frequency shift itself. Allowed range is-INT_MAXtoINT_MAX. Default?0.0.levelโ output gain slapped onto the final output. Allowed range is0.0to1.0. Default is1.0.orderโ the filter order used for filtering. Allowed range is1to16. Default is8.
Commands
This filter supports all of the above options as commands ๐
afwtdn ๐
Reduces broadband noise from your input samples using Wavelets. It's giving noise-cancelling headphones but make it math.
Here's the description of the accepted options:
sigmaโ sets the noise sigma, allowed range is0to1. Default value is0. This one controls the strength of the denoising applied to input samples. Most useful way to set this is via decibels, like-45dB.levelsโ the number of wavelet levels of decomposition. Allowed range is1to12. Default is10. Set this too low and the denoising performance gets very poor, like genuinely embarrassing.wavetโ the wavelet type used for decomposition of the input frame. They're sorted by number of coefficients, lowest to highest. More coefficients means worse filtering speed, but overall better quality. Available wavelets are:sym2sym4rbior68deb10sym10coif5bl3
percentโ sets the percent of full denoising. Allowed range is0to100percent. Default value is85percent, aka partial denoising.profileโ if enabled, the first input frame will be used as the noise profile. Heads up though: if that first frame's samples contain non-noise, performance will be very poor ๐ญadaptiveโ 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.samplesโ sets the size of a single frame in number of samples. Allowed range is512to65536. Default frame size is8192samples.softnessโ sets the softness applied inside the thresholding function. Allowed range is0to10. Default softness is1.
Commands
This filter supports all of the above options as commands ๐ซถ
agate ๐ช
A gate is mainly used to reduce the lower parts of a signal. This kind of signal processing reduces that annoying disturbing noise between the useful signals. Very "bouncer at the club, only the loud stuff gets in" energy ๐
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. Because an exact manipulation of the signal would cause distortion of the waveform, the reduction can be levelled over time. That's what attack and release are for.
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. Shorter signals than the chosen attack time will be left untouched, bestie โ they get a free pass โจ
level_inโ sets the input level before filtering. Default is1. Allowed range is0.015625to64.modeโ sets the mode of operation. Can be"upward"or"downward". Default is"downward". If set to"upward"mode, higher parts of the signal get amplified, expanding the dynamic range in the upward direction. Otherwise, in the case of"downward", lower parts of the signal get reduced.rangeโ sets the level of gain reduction when the signal is below the threshold. Default is0.06125. Allowed range is0to1. Setting this to0disables reduction entirely, and then the filter behaves like an expander.thresholdโ if a signal rises above this level, the gain reduction is released. Default is0.125. Allowed range is0to1.ratioโ sets a ratio by which the signal is reduced. Default is2. Allowed range is1to9000.attackโ the amount of milliseconds the signal has to rise above the threshold before gain reduction stops. Default is20milliseconds. Allowed range is0.01to9000.releaseโ the amount of milliseconds the signal has to fall below the threshold before the reduction is increased again. Default is250milliseconds. Allowed range is0.01to9000.makeupโ sets the amount of amplification of the signal after processing. Default is1. Allowed range is1to64.kneeโ curves the sharp knee around the threshold so it enters gain reduction more softly. Default is2.828427125. Allowed range is1to8.detectionโ choose whether the exact signal should be taken for detection or an RMS-like one. Default is"rms". Can be"peak"or"rms".linkโ choose whether the average level between all channels or the louder channel affects the reduction. Default is"average". Can be"average"or"maximum".
Commands
This filter supports all of the above options as commands ๐
aiir ๐๏ธ
Applies an arbitrary Infinite Impulse Response filter. Yes, arbitrary. Go off, king.
It accepts the following parameters:
zeros,zโ set B/numerator/zeros/reflection coefficients.poles,pโ set A/denominator/poles/ladder coefficients.gains,kโ set channels gains.dry_gainโ set input gain.wet_gainโ set output gain.format,fโ set the coefficients format:llโ lattice-ladder functionsfโ analog transfer functiontfโ digital transfer functionzpโ Z-plane zeros/poles, cartesian (this is the default โจ)prโ Z-plane zeros/poles, polar radianspdโ Z-plane zeros/poles, polar degreesspโ S-plane zeros/poles
process,rโ set the type of processing:dโ direct processingsโ serial processingpโ parallel processing
precision,eโ set the filtering precision:dblโ double-precision floating-point (default)fltโ single-precision floating-pointi32โ 32-bit integersi16โ 16-bit integers
normalize,nโ normalize the filter coefficients. By default this is enabled. Enabling it normalizes the magnitude response at DC to0dB.mixโ how much to use the filtered signal in the output. Default is1. Range is between0and1.responseโ show IR frequency response: magnitude (magenta), phase (green) and group delay (yellow) in an additional video stream. By default it's disabled.channelโ set which IR channel to display the frequency response for. By default the first channel is displayed. This option is used only whenresponseis enabled.sizeโ set the video stream size. This option is used only whenresponseis enabled.
Coefficients in "tf" and "sf" format are separated by spaces and are in ascending order.
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 ๐ฆ
You can provide different coefficients and gains for every channel โ in that case, use '|' to separate the coefficients or gains. The last provided coefficients get used for all the remaining channels.
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 analog transfer function format:
aiir=z=1.3057 0 0 0:p=1.3057 2.3892 2.1860 1:f=sf:r=d
alimiter ๐ง
The limiter prevents an input signal from rising over a desired threshold. This one uses lookahead technology to keep your signal from distorting ๐ That means there's a small delay after the signal is processed, so keep in mind that the delay it produces is the attack time you set. Not a bug, it's a feature, iykyk.
The filter accepts the following options:
level_inโ set input gain. Default is1.level_outโ set output gain. Default is1.limitโ don't let signals above this level pass the limiter. Default is1.attackโ the limiter will reach its attenuation level in this amount of time in milliseconds. Default is5milliseconds.releaseโ come back from limiting to attenuation1.0in this amount of milliseconds. Default is50milliseconds.ascโ 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.asc_levelโ select how much the release time is affected by ASC.0means nearly no changes in release time, while1produces higher release times.levelโ auto level the output signal. Default is enabled. This normalizes audio back to0dBif enabled.latencyโ compensate the delay introduced by using the lookahead buffer set with theattackparameter. Also flushes the valid audio data in the lookahead buffer when the stream hits EOF.
Depending on the setting you picked, it's recommended to upsample the input 2x or 4x times with aresample before applying this filter ๐
allpass ๐
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. Sneaky like that ๐ธ
The filter accepts the following options:
frequency,fโ set frequency in Hz.width_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 inwidth_typeunits.mix,mโ how much to use the filtered signal in the output. Default is1. Range is between0and1.channels,cโ tells the filter which channels to actually filter. Default is all the ones you've got ๐normalize,nโ normalizes the biquad coefficients. Off by default, bestie. Turn it on and it normalizes the magnitude response at DC to 0dB โจorder,oโ sets the filter order. Can be1or2. Default is2๐transform,aโ sets the transform type of the IIR filter. The options are giving range:didiitditdiilattsvfzdf
precision,rโ sets the precision of the filtering. Pick your fighter:autoโ picks the automatic sample format depending on the surround filters ๐s16โ always use signed 16-bits32โ always use signed 32-bitf32โ always use float 32-bitf64โ always use float 64-bit
Commands ๐
This filter supports the following commands, and yes they're all lowkey the same vibe:
frequency,fโ change allpass frequency. The syntax for the command is:"frequency"โจwidth_type,tโ change allpass width_type. Syntax is:"width_type"width,wโ change allpass width. Syntax is:"width"mix,mโ change allpass mix. Syntax is:"mix"
๐ aloop
Loops your audio samples. It's giving replay button, fr fr ๐
The filter accepts the following options:
loopโ sets the number of loops. Setting this value to-1will result in infinite loops. Default is0๐sizeโ sets the maximal number of samples. Default is0startโ sets the first sample of the loop. Default is0timeโ sets the time of loop start, in seconds. Only used if the option namedstartis set to-1โญ
๐ซถ amerge
Merges two or more audio streams into a single multi-channel stream. Glow-up for your channels โจ
All inputs must have the same sample rate, and format. No mixing and matching, bestie.
If the inputs don't have the same duration, the output will stop with the shortest one. Shortest king wins, I don't make the rules ๐ญ
The filter accepts the following options:
inputsโ sets the number of inputs. Default is2layout_modeโ this one controls how the output channel layout is determined, and whether the audio channels get reordered during the merge. Three moods:legacyโ this is the mode the filter behaved historically in, so it's the default ๐
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 the following 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) ๐
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. Yeah. It's giving chaos 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. That's it, that's the whole vibe.
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 ๐ธ
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 project that actually works ๐ซถ
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. Not me inserting a whole filter for you ๐
It accepts the following parameters:
inputsโ the number of inputs. If unspecified, it defaults to2durationโ how to determine the end-of-stream:longestโ the duration of the longest input. (default) ๐shortestโ the duration of the shortest inputfirstโ the duration of the first input
dropout_transitionโ the transition time, in seconds, for volume renormalization when an input stream ends. The default value is2secondsweightsโ 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 is1โญnormalizeโ always scale inputs instead of only doing summation of samples.
Beware of heavy clipping if inputs are not normalized prior or after filtering by this filter if this option is disabled ๐ญ By default it's enabled.
Examples โจ
- 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 ๐
This filter supports the following commands:
weightsnormalize
Syntax is same as the option with the same name. Copy paste energy, but make it a command โจ
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. Math but make it audio ๐ฅ
With this element-wise multiplication you can create amplitude fades and amplitude modulations. Iconic behaviour, honestly ๐
๐ anequalizer
A high-order parametric multiband equalizer, for each channel. It's giving main character EQ ๐
It accepts the following parameters:
paramsโ this option string is in format:"cchn f=cf w=w g=g t=f | ..."Each equalizer band is separated by'|'. Let's break it down:chnโ set the channel number to which equalization will be applied. If the input doesn't have that channel, the entry is ignored ๐fโ set the central frequency for the band. If the input doesn't have that frequency, the entry is ignoredwโ set the band width in Hertzgโ set the band gain in dBtโ set the filter type for the band. Optional, and can be:0โ Butterworth, this is default ๐1โ Chebyshev type 12โ Chebyshev type 2
curvesโ with this option activated, the frequency response ofanequalizeris displayed in the video stream. Visuals, we love to see it โจsizeโ sets the video stream size. Only useful if thecurvesoption is activatedmgainโ sets 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 activatedfscaleโ sets the frequency scale used to draw the frequency response in the video output. Can belinearorlogarithmic. Default islogarithmic๐colorsโ sets 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 ๐ค
Examples โจ
- 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 ๐
This filter supports the following commands:
changeโ alter existing filter parameters. The syntax for the commands is:"fN|f=freq|w=width|g=gain"
fN is the existing filter number, starting from 0 โ 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.
A 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. Your audio's skincare routine, no cap ๐งโโ๏ธ
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. Detectives, but for waveforms ๐
The filter accepts the following options:
strength,sโ sets the denoising strength. Allowed range is from0.00001to10000. Default value is0.00001โญpatch,pโ sets the patch radius duration. Allowed range is from1to100milliseconds. Default value is2millisecondsresearch,rโ sets the research radius duration. Allowed range is from2to300milliseconds. Default value is6millisecondsoutput,oโ sets the output mode. It accepts the following values:iโ pass input unchangedoโ pass noise filtered outnโ pass only noise
Default value is o ๐
smooth,mโ sets the smooth factor. Default value is11. Allowed range is from1to1000
Commands ๐
This filter supports the all above options as commands. Yes, the all above options โ we love the grammar, it ate ๐
๐ง anlmf, anlms
Applies the Normalized Least-Mean-(Squares|Fourth) algorithm to the first audio stream using the second audio stream. Two filters, one algorithm family, very sibling energy ๐ฏโโ๏ธ
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 (difference between the desired, 2nd input audio stream and the actual signal, the 1st input audio stream). It's literally learning in real time, obsessed ๐ญ
A description of the accepted options follows.
orderโ sets the filter ordermuโ sets the filter muepsโ sets the filter'seps. that's it, that's the whole vibe โจleakageโ sets the filterleakage. lowkey a lil leaky on purpose, iykyk ๐out_modeโ picks which signal actually slides out the other side. the options are:iโ pass the 1st input. straightforward icon behavior ๐dโ pass the 2nd input.oโ pass the difference between the desired signal, the 2nd input, and the error signal estimate.nโ pass the difference between the input, the 1st input, and the error signal estimate.eโ pass the error signal's estimated samples.
default value is o, bestie ๐ซถ
precisionโ tells it how much precision to flex when processing samples:autoโ auto-pick the internal sample format depending on the other filters. let it cook ๐ฅfloatโ always use single-floating point precision sample format.doubleโ always use double-floating point precision sample format. max effort, no notes ๐
Examples
one of the many usages of this filter is noise reduction โ the input audio gets filtered with the same samples delayed by a fixed amount. here's one such example for stereo audio, and yes the line is long, just copy it exactly bestie:
asplit[a][b],[a]adelay=32S|32S[a],[b][a]anlms=order=128:leakage=0.0005:mu=.5:out_mode=o
Commands
this filter supports the same commands as options, except the option order. everything else? command-able, periodt ๐
anull
passes the audio source through to the output completely unchanged. it's giving "i'm just here for moral support" ๐ซถ zero drama, zero processing, iconic.
apad
pads the end of an audio stream with silence. yes bestie, it's the "we need more runtime" filter ๐ธ
this can be used together with ffmpeg -shortest to extend audio streams to the same length as the video stream. very demure, very matching-lengths ๐
a description of the accepted options follows:
packet_sizeโ set the 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_lenโ pick one, you cannot have both 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. only used if set to a 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. only used if set to a 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 the pad_len nor the whole_len nor pad_dur nor whole_dur option is set, the filter will add silence to the end of the input stream indefinitely. no cap, it will just keep going ๐
note that forffmpeg4.4 and earlier, a zeropad_durorwhole_duralso caused the filter to add silence indefinitely. different era, same chaos ๐
Examples
- add
1024samples of silence to the end of the input:
apad=pad_len=1024
- make sure the audio output will contain at least
10000samples, and 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
adds a phasing effect to the input audio 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. it's giving ocean wave but make it audio ๐
a description of the accepted parameters follows:
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, but make it phase โจ
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.
Commands
this filter supports all the above options as commands. every single one, we love a flexible queen ๐
apsnr
measure Audio Peak Signal-to-Noise Ratio. it's a vibe check for your audio, fr fr ๐
this filter takes two audio streams for input, and outputs the first audio stream. results are in dB per channel at end of either input. so polite, it reports back at the end ๐ซถ
apsyclip
apply a Psychoacoustic clipper to the input audio stream. crunchy but make it science ๐ฅ
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. little peek behind the curtain ๐adaptiveโ set strength of adaptive distortion applied. default value is0.5. allowed range is from0to1.iterationsโ set number of iterations of the psychoacoustic clipper. allowed range is from1to20. default value is10.levelโ auto level the output signal. default is disabled. this normalizes audio back to0dBFSif enabled.
Commands
this filter supports all the above options as commands. iconic behavior ๐
apulsator
audio pulsator is something between an autopanner and a tremolo. but it can produce funny stereo effects as well ๐
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 has the ability to define an offset between left and right channel.
an offset of 0 means that both LFO shapes match each other โ the left and right channel are altered equally, which is 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), and pulsator acts as an autopanner. at 1 both curves match again. every setting in between moves the phase shift gaplessly 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. physics but make it a bop ๐ซ
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 the waveform shape the LFO will use. can be one of:sine,triangle,square,sawuporsawdown. default issine.amountโ set modulation. defines how much of the 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. it's the "i'll figure it out" filter ๐ง
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 ๐
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.
Examples
- 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 ๐ yes, it does exactly what it says, no plot twist.
warning: this filter requires memory to buffer the entire clip, so trimming is suggested. it's a hungry girl, feed it less audio ๐ญ
Examples
- take the first 5 seconds of a clip, and reverse it:
atrim=end=5,areverse
arls
apply the Recursive Least Squares algorithm to the first audio stream using the second audio stream. math girlies rise ๐
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 (the difference between the desired, 2nd input audio stream and the actual signal, the 1st input audio stream).
a description of the accepted options follows:
orderโ set the filter order.lambdaโ set the forgetting factor. it forgives, but it doesn't forget... until lambda says so ๐deltaโ set the coefficient to initialize the 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 the difference between the desired signal, the 2nd input, and the error signal estimate.nโ pass the difference between the input, the 1st input, and the error signal estimate.eโ pass the error signal's estimated samples.
default value is o ๐ซถ
precisionโ set which precision to use when processing samples:autoโ auto-pick the internal sample format depending on the other filters.floatโ always use single-floating point precision sample format.doubleโ always use double-floating point precision sample format. go big or go home ๐
arnndn
reduce noise from speech using Recurrent Neural Networks ๐ง โจ your voice, but with the background chaos politely escorted out.
this filter accepts the following options:
model,mโ set the train model file to load. this option is always required. no model, no filter, that's the rule bestie ๐ธmixโ sets how much of the filtered samples get mixed back into the final output, bestie. Allowed range is from-1to1, and the default is1. Negative values are โจspecialโจ โ they set how much of the filtered noise you keep in the final output instead. Set this to-1if you literally want to hear the actual noise that got removed from the input signal. ๐
Commands
This filter supports the all above options as commands. ๐ซถ
asdr
Measures the Audio Signal-to-Distortion Ratio, no cap. ๐
This filter takes two audio streams as input, and outputs the first audio stream. Results are in dB per channel, delivered at the end of either input. ๐
asetnsamples
Sets the number of samples in each output audio frame. ๐ง
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. So like, don't panic if the last one looks different. ๐ญ
The filter accepts the following options:
nb_out_samples,nโ sets the number of frames per each output audio frame. The number is intended as the number of samples per each channel. Default value is1024.pad,pโ if set to1, the filter pads the last audio frame with zeroes so that the last frame contains the same number of samples as the previous ones. Default value is1.
For example, to set the number of per-frame samples to 1234 and disable padding for the last frame, use:
asetnsamples=n=1234:p=0
asetrate
Sets the sample rate without altering the PCM data. Heads up: this results in a change of speed and pitch. ๐ต (iykyk โ chipmunk mode incoming.)
The filter accepts the following options:
sample_rate,rโ sets the output sample rate. Default is44100Hz.
ashowinfo
Shows one line containing various info for each input audio frame. The input audio is not modified โ it's purely here to spill the tea. โ
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, 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.plane_checksumsโ a list of Adler-32 checksums for each data plane.
asisdr
Measures the Audio Scaled-Invariant Signal-to-Distortion Ratio. Fancy name, iconic job. ๐
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.
asoftclip
Applies audio soft clipping. ๐ธ
Soft clipping is a type of distortion effect where the amplitude of a signal is saturated along a smooth curve, rather than the abrupt shape of hard-clipping. It's giving gentle glow-up instead of a brick wall ๐.
This filter accepts the following options:
typeโ sets the type of soft-clipping.
It accepts the following values:
hardtanhatancubicexpalgquinticsinerf
thresholdโ sets the threshold from where to start clipping. Default value is0dBor1.outputโ sets the gain applied to output. Default value is0dBor1.paramโ sets an additional parameter which controls the sigmoid function.oversampleโ sets the oversampling factor.
Commands
This filter supports the all above options as commands. 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. ๐ฆ
It accepts the following option:
win_sizeโ sets the window length in samples. Default value is2048. Allowed range is from32to65536.win_funcโ sets the window function.
It accepts the following values:
rectbartletthann,hanninghammingblackmanwelchflattopbharrisbnuttallbhannsinenuttalllanczosgausstukeydolphcauchyparzenpoissonbohmankaiser
Default is "hann".
overlapโ sets the window overlap. Allowed range is from0to1. Default value is0.5.measureโ selects 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
asr
Automatic Speech Recognition ๐ค โ literally the filter that listens so you don't have to.
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 sets the sampling rate of the input audio. Default is16000. This needs to match the speech models, otherwise you'll get poor results. (Vibe check your models first, bestie. ๐)hmmโ sets the dictionary containing acoustic model files.dictโ sets the pronunciation dictionary.lmโ sets the language model file.lmctlโ sets the language model set.lmnameโ sets which language model to use.logfnโ sets the output for log messages.
The filter exports recognized speech as the frame metadata "lavfi.asr.text". โจ
astats
Displays time-domain statistical info about the audio channels. Stats 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 sets metadata injection. All the metadata keys are prefixed with"lavfi.astats.X", whereXis the channel number starting from1, or the string"Overall". 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".
Read below for the description of the keys. ๐
resetโ sets the number of frames over which cumulative stats are calculated before being reset. Default is disabled.measure_perchannelโ selects 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 selects 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. the 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.
asubboost
Boosts subwoofer frequencies. ๐ Turn the bass all the way up, respectfully.
The filter accepts the following options:
dryโ sets the dry gain, i.e. how much of the original signal is kept. Allowed range is from0to1. Default value is1.0.wetโ sets the wet gain, i.e. how much of the filtered signal is kept. Allowed range is from0to1. Default value is1.0.boostโ sets the max boost factor. Allowed range is from1to12. Default value is2.decayโ sets the delay line decay gain value. Allowed range is from0to1. Default value is0.0.feedbackโ sets the delay line feedback gain value. Allowed range is from0to1. Default value is0.9.cutoffโ sets the cutoff frequency in Hertz. Allowed range is50to900. Default value is100.slopeโ sets how steep the cutoff slope is ๐ข allowed range is0.0001to1, and the default is0.5.delayโ sets the delay, bestie. allowed range is1to100, default20.channelsโ picks which channels get processed. default is literally all available ones ๐
โจ Commands โจ
this filter supports all of the above options as commands, periodt ๐
๐ฆ asubcut
cuts the subwoofer frequencies. like, bye bass ๐
the whole point of this one is that it lets you set a custom, steeper roll off than highpass gives you, so it can attenuate the frequency content in the stop-band way more aggressively. it's giving extra-strength ๐ช
here's what it accepts:
cutoffโ cutoff frequency in Hertz. allowed range is2to200. default20.orderโ the filter order. available values are3to20. default10.levelโ input gain level. allowed range is0to1. default1.
Commands
this filter supports all the above options as commands ๐
๐ asupercut
cut super frequencies โ๏ธโจ
options:
cutoffโ cutoff frequency in Hertz. allowed range is20000to192000. default20000.orderโ filter order. available values are3to20. default10.levelโ input gain level. allowed range is0to1. default1.
Commands
yep, all the above options work as commands ๐ซถ
๐ asuperpass
applies a high order Butterworth band-pass filter. fancy name, iconic behaviour ๐
options:
centerfโ center frequency in Hertz. allowed range is2to999999. default1000.orderโ filter order. available values are4to20. default4.qfactorโ the Q-factor. allowed range is0.01to100. default1.levelโ input gain level. allowed range is0to2. default1.
Commands
all of the above = commands, no cap ๐
โญ asuperstop
applies a high order Butterworth band-stop filter. the anti-band-pass, if you will ๐
options:
centerfโ center frequency in Hertz. allowed range is2to999999. default1000.orderโ filter order. available values are4to20. default4.qfactorโ Q-factor. allowed range is0.01to100. default1.levelโ input gain level. allowed range is0to2. default1.
Commands
all above options, usable as commands ๐
๐ง atempo
adjusts the audio tempo. the speed-up/slow-down filter, and it does it without touching the pitch, which is lowkey the coolest thing ever โจ
it accepts exactly one parameter: the audio tempo. if you don't specify it, the filter assumes the nominal 1.0 tempo. tempo has to be in the [0.5, 100.0] range.
โ ๏ธ heads up bestie: tempo greater than2will skip some samples rather than blending them in. if that's a problem for any reason, you can always daisy-chain severalatempoinstances to get the product tempo you want ๐ซถ
Examples
- slow the audio down to 80% tempo:
atempo=0.8
- speed the audio up to 300% tempo:
atempo=3
- speed it up to 300% by daisy-chaining two
atempoinstances:
atempo=sqrt(3),atempo=sqrt(3)
Commands
this filter supports these commands:
tempoโ changes the filter tempo scale factor. syntax for the command is:"tempo"
๐ธ atilt
applies a spectral tilt filter to the audio stream. it can apply any spectral roll-off slope over any frequency band you specify ๐ข
options:
freqโ central frequency of the tilt, in Hz. default is10000Hz.slopeโ slope direction of the tilt. default is0. allowed range is-1to1.widthโ width of the tilt. default is1000. allowed range is100to10000.orderโ order of the tilt filter.levelโ input volume level. allowed range is0to4. default is1.
Commands
all of the above options double as commands ๐๐
๐ atrim
trims the input so the output contains one continuous subpart of it. it's the scissors filter โ๏ธ
it takes these parameters:
startโ timestamp (in seconds) of the start of the section to keep. like, the audio sample with the timestamp start becomes the first sample in the output.endโ the time of the first audio sample that gets dropped. i.e. the sample immediately before the one with the timestamp end is the last sample in the output.start_ptsโ same asstart, except this one sets the start timestamp in samples instead of seconds.end_ptsโ same asend, except this 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 โ peep the Time duration section in the ffmpeg-utils(1) manual if you need the deets ๐
๐ okay so this part matters: the first two sets of start/end options 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, this filter doesn't modify the timestamps at all. if you want the output timestamps to start at zero, put theasetptsfilter afteratrim.
if you set multiple start or end options, this filter tries to be greedy and keeps all samples matching at least one of the constraints. want only the part that matches all the constraints at once? chain multiple atrim filters, bestie ๐ซถ
the defaults are set so that all the input is kept. so you can totally set, like, just the end values to keep everything before the specified time.
Examples
- 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
๐ฅ axcorrelate
calculates the normalized windowed cross-correlation between two input audio streams. very math, very main character energy ๐งฎโจ
the resulting samples are always between -1 and 1 inclusive. if the result is 1 it means the two input samples are highly correlated in that selected segment. result 0 means they're not correlated at all. and if the result is -1 it means the two input samples are out of phase, meaning they cancel each other out ๐
options:
sizeโ sets the size of the segment over which cross-correlation is calculated. default is256. allowed range is2to131072.algoโ sets the algorithm for cross-correlation. can be"slow","fast"or"best". default is"best". the fast algorithm assumes mean values over any given segment are always zero, and so it needs way fewer calculations to do its thing. that's generally not true, but it is valid for typical audio streams ๐ง
Examples
- calculate the correlation between channels in a stereo audio stream:
ffmpeg -i stereo.wav -af channelsplit,axcorrelate=size=1024:algo=fast correlation.wav
๐ง bandpass
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 (that's 20dB per decade, iykyk) ๐
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 used to specify the band-width of the filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specifies the band-width of the filter, inwidth_typeunits.mix,mโ how much of the filtered signal goes into the output. default is1. range is between0and1.channels,cโ which channels to filter. by default all available channels are filtered.normalize,nโ normalize the biquad coefficients. disabled by default. turning it on normalizes the magnitude response at DC to 0dB.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 you set this value 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'll just produce nasty artifacts ๐คข
๐ also note: the filter delay will be exactly this many samples when this is set to a non-zero value.
Commands
this filter supports these commands:
frequency,fโ change the bandpass frequency. syntax for the command is:"frequency"width_type,tโ change the bandpass width_type. syntax for the command is:"width_type"width,wโ change the bandpass width. syntax for the command is:"width"mix,mโ change the bandpass mix. syntax for the command is:"mix"
๐ bandreject
applies a two-pole Butterworth band-reject filter with central frequency frequency and (3dB-point) band-width width. it rolls off at 6dB per octave (20dB per decade) ๐
options:
frequency,fโ sets the filter's central frequency. default is3000.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 the filter, inwidth_typeunits.mix,mโ how much of the filtered signal goes into the output. default is1. range is between0and1.channels,cโ which channels to filter. by default all available channels are filtered.normalize,nโ normalize the biquad coefficients. disabled by default. enabling it normalizes the magnitude response at DC to 0dB.transform,aโ sets the transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ sets the precision of filtering.autoโ picks the sample format automatically, based on whatever the surround filters are doing โจs16โ always signed 16-bit, periodt.s32โ always signed 32-bit, no cap.f32โ always float 32-bit, she's โจpreciseโจ.f64โ always float 64-bit, maximum delulu precision ๐block_size,bโ sets the block size used for reverse IIR processing ๐ if you set it high enough (higher than the impulse response length truncated when it reaches near-zero values) the filtering becomes linear phase โ iconic. but if it's not big enough it will literally just produce nasty artifacts ๐ญ
heads up bestie: the filter delay will be exactly this many samples when you set it to a non-zero value. fr fr.
Commands
This filter supports the following commands:
frequency,fโ change bandreject frequency. Syntax for the command is:"frequency"width_type,tโ change bandreject width_type. Syntax for the command is:"width_type"width,wโ change bandreject width. Syntax for the command is:"width"mix,mโ change bandreject mix. Syntax for the command is:"mix"
bass, lowshelf
Boost or cut the bass (lower) frequencies of the audio, using a two-pole shelving filter with a response similar to that of a standard hi-fi's tone-controls ๐ง this is also known as shelving equalisation (EQ), iykyk.
The filter accepts the following options:
gain,gโ give the gain at 0 Hz. 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, that's the vibe check you do NOT want to fail.frequency,fโ set the filter's central frequency, so you can extend or reduce the frequency range to be boosted or cut. Default value is100Hz. ๐width_type,tโ set the method to specify band-width of filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ determines how steep the filter's shelf transition is ๐poles,pโ set number of poles. Default is2.mix,mโ how much to use the filtered signal in the output. Default is1. Range is between0and1. ๐channels,cโ specify 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 to0dBโจtransform,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 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 ๐ญ
note that the filter delay will be exactly this many samples when set to a non-zero value. ๐ซถ
Commands
This filter supports the following commands:
frequency,fโ change bass frequency. Syntax for the command is:"frequency"width_type,tโ change bass width_type. Syntax for the command is:"width_type"width,wโ change bass width. Syntax for the command is:"width"gain,gโ change bass gain. Syntax for the command is:"gain"mix,mโ change bass mix. Syntax for the command is:"mix"
biquad
Apply a biquad IIR filter with the given coefficients ๐งฎ where b0, b1, b2 and a0, a1, a2 are the numerator and denominator coefficients respectively. and channels, c specify which channels to filter, by default all available are filtered.
Commands
This filter supports the following commands:
a0a1a2b0b1b2โ change biquad parameter. Syntax for the command is:"value"mix,mโ how much to use the filtered signal in output. Default is1. Range is between0and1.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 to0dB. โจtransform,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 a high enough value (higher than the impulse response length truncated when it reaches near zero values) filtering will become linear phase; otherwise, if 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.
bs2b
Bauer stereo to binaural transformation, which improves headphone listening of stereo audio records ๐ง๐ฆ
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
Remap input channels to new locations ๐บ๏ธโจ
It accepts the following parameters:
mapโ map 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_channelis not given then it is 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 ๐คchannel_layoutโ the channel layout of the output stream. If not specified, then 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 ๐
If no mapping is present, the filter will implicitly map input channels to output channels, preserving indices.
Examples
- 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. ๐
- 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
Split each channel from an input audio stream into a separate output stream ๐ like, one stream per channel, she's organized.
It accepts the following parameters:
channel_layoutโ the channel layout of the input stream. The 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. The default is"all".
choosing channels not present in the channel layout in the input will result in an error โ ๏ธ
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, one containing only the left channel and the other the right channel โจ
- 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
Add a chorus effect to the audio ๐ธ
Can make a single vocal sound like a chorus, but can also be applied to instrumentation. She's versatile, okurrr.
Chorus resembles an echo effect with a short delay, but whereas with echo the delay is constant, with chorus it is varied using sinusoidal or triangular modulation. The modulation depth defines the range the modulated delay is played before or after the delay. Hence the delayed sound will sound slower or faster, that is the delayed sound tuned around the original one, like in a chorus where some vocals are slightly off key ๐ถ๐
It accepts the following parameters:
in_gainโ set input gain. Default is0.4.out_gainโ set output gain. Default is0.4.delaysโ set delays. A typical delay is around40msto60ms.decaysโ set decays.speedsโ set speeds.depthsโ set 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
Compress or expand the audio's dynamic range ๐๏ธโจ
It accepts the following parameters:
attacksdecaysโ a list of times in seconds for each channel over which the instantaneous level of the input signal is averaged to determine its volume.attacksrefers to increase of volume anddecaysrefers to decrease of volume. For most situations, the attack time (response to the 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 is0.3seconds and a typical value for decay is0.8seconds. If the specified number of attacks & decays is lower than the number of channels, the last set attack/decay will be used for all remaining channels ๐ซถpointsโ the list of points for the transfer function, given in dB relative to the maximum possible signal amplitude, bestie. Each key points list has to be defined with this syntax:"x0/y0|x1/y1|x2/y2|...."or"x0/y0 x1/y1 x2/y2 ...."
The input values have to be in strictly increasing order, but lowkey the transfer function does not have to be monotonically rising. The point "0/0" is assumed but can be overridden (by "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. It defaults to0.01. ๐gainโ sets the additional gain in dB to be applied at all points on the transfer function, so you can adjust the overall gain super easily. It defaults to0.volumeโ sets an initial volume, in dB, to be assumed for each channel when filtering starts. This lets you supply a nominal level up front so that, for example, a very large gain is not applied to initial signal levels before the companding has begun to operate. A typical value for audio that's initially quiet is-90dB. It defaults to0.delayโ sets a delay, in seconds. The input audio is analyzed immediately, but the audio is delayed before being fed to the volume adjuster. Specifying a delay approximately equal to the attack/decay times lets the filter effectively operate in predictive rather than reactive mode. It defaults to0.
โจ Examples โจ
- Make music with both quiet and loud passages suitable for listening to in a noisy environment:
compand=.3|.3:1|1:-90/-60|-60/-40|-40/-30|-20/-20:6:0:-90:0.2
- Another example for audio with whisper 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 (making 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
๐ธ compensationdelay ๐ธ
The Compensation Delay Line is a metric-based delay to compensate for differing positions of microphones or speakers. Iconic, honestly.
So like, say you recorded guitar with two microphones placed in different locations. Because the front of the sound wave has a fixed speed in normal conditions, the phasing of the microphones can vary and depends on their location and interposition. The best sound mix can be achieved when these microphones are in phase (synchronized). Note that a distance of ~30 cm between microphones makes one microphone capture the signal in antiphase to the other microphone โ and that makes the final mix sound moody ๐ญ. This filter helps solve phasing problems by adding different delays to each microphone track and making them synchronized. Slay.
The best result can be reached when you take one track as base and synchronize other tracks one by one with it. Remember that synchronization/delay tolerance depends on sample rate, too โ higher sample rates will give more tolerance. No cap.
The filter accepts the following parameters:
mmโ set millimeters distance. This is compensation distance for fine tuning. Default is0.cmโ set cm distance. This is compensation distance for tightening distance setup. Default is0.mโ set meters distance. This is compensation distance for hard distance setup. Default is0.dryโ set dry amount. Amount of unprocessed (dry) signal. Default is0.wetโ set wet amount. Amount of processed (wet) signal. Default is1.tempโ set temperature in degrees Celsius. This is the temperature of the environment. Default is20.
Commands
This filter supports all the above options as commands. ๐
๐ฆ crossfeed ๐ฆ
Apply the 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 extreme stereo separation of low frequencies.
The intent is to produce a more speaker-like sound to the listener. Periodt.
The filter accepts the following options:
strengthโ set the strength of 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-30dbwhen strength is set to1.rangeโ set soundstage wideness. Default is0.5. Allowed range is from0to1. This sets the cut off frequency of the low shelf filter. Default is cut off 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 input gain. Default is0.9.level_outโ set output gain. Default is1.block_sizeโ set 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
This filter supports all the above options as commands โจ.
๐ crystalizer ๐
A simple algorithm for audio noise sharpening.
This filter linearly increases the differences between each audio sample.
The filter accepts the following options:
iโ sets the intensity of the effect (default:2.0). Must be in range between-10.0to0(unchanged sound) to10.0(maximum effect). To do inverse filtering, use a negative value.cโ enable clipping. By default it's enabled.
Commands
This filter supports all the above options as commands.
๐ dcshift ๐
Apply a DC shift to the audio.
This can be useful to remove a DC offset (caused perhaps by a hardware problem in the recording chain) from the audio. The effect of a DC offset is reduced headroom and hence volume. The astats filter can be used to determine if a signal has a DC offset. Good to know tbh.
shiftโ set the DC shift, allowed range is[-1, 1]. It indicates the amount to shift the audio.limitergainโ optional. It should have a value much less than1(e.g.0.05or0.02) and is used to prevent clipping.
๐ deesser ๐
Apply de-essing to the audio samples.
iโ set intensity for triggering de-essing. Allowed range is from0to1. Default is0.mโ set amount of ducking on the treble part of 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 the following values:
iโ pass input unchanged.oโ pass ess filtered out.eโ pass only ess.
Default value is o.
๐ dialoguenhance ๐
Enhance dialogue in stereo audio.
This filter accepts stereo input and produces surround (3.0) channels output. The newly produced front center channel has enhanced speech dialogue originally available in both stereo channels. This filter outputs front left and front right channels the same as available in the stereo input. Main character energy fr fr.
The filter accepts the following 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 the above options as commands ๐ซถ.
โญ drmeter โญ
Measure audio dynamic range.
DR values of 14 and higher are found in very dynamic material. DR of 8 to 13 is found in transition material. And anything less than 8 has very poor dynamics and is very compressed.
The filter accepts the following options:
lengthโ set the window length in seconds used to split the audio into segments of equal length. Default is3seconds.
๐ dynaudnorm ๐
Dynamic Audio Normalizer.
This filter applies a certain amount of gain to the input audio in order to bring its peak magnitude to a target level (e.g. 0 dBFS). However, in contrast to more "simple" normalization algorithms, the Dynamic Audio Normalizer dynamically re-adjusts the gain factor to the input audio. This lets you apply extra gain to the "quiet" sections of the audio while avoiding distorting or clipping the "loud" sections. In other words: the Dynamic Audio Normalizer will "even out" the volume of quiet and loud sections, in the sense that the volume of each section is brought to the same target level. Note, however, that the Dynamic Audio Normalizer achieves this goal without applying "dynamic range compressing". It will retain 100% of the dynamic range within each section of the audio file. Obsessed, honestly ๐ฅ.
framelen,fโ sets the frame length, in milliseconds. Valid range is10to8000ms, default is500ms. Okay so real talk: the Dynamic Audio Normalizer chews through your audio in little chunks called frames, and it has to do this because a peak magnitude means literally nothing for one single sample value ๐ โ you need a whole contiguous run of samples to figure out what the peak actually is. A "standard" normalizer would just grab the peak of the entire file, but this one is extra and finds the peak individually for every frame. Frame length is given in ms, and the default500ms has been found to give good results with most files. Oh and heads up: the exact frame length in samples gets determined automatically from the sampling rate of each individual input audio file โจgausssize,gโ sets the Gaussian filter window size. Range3to301, and it must be an odd number. Default is31. This is probably the most important parameter in the whole Dynamic Audio Normalizer, no cap. The window size is specified in frames, centered on the current frame, and for simplicity's sake it has to be odd. So the default31means: the current frame, plus the15frames before it, plus the15frames after it ๐ซถ Bigger window โ stronger smoothing โ less gain variation โ slower gain adaptation. Smaller window โ weaker smoothing โ more gain variation โ faster gain adaptation. In other words bestie, crank this up and it starts acting like a "traditional" normalization filter; dial it down and it starts acting like a dynamic range compressor. Pick your fighter ๐peak,pโ sets the target peak value, i.e. the highest permissible magnitude level for the normalized audio. The filter tries to get as close to that target as it can while making absolutely sure the normalized signal never exceeds it ๐ฅ A frame's maximum local gain factor is imposed directly by the target peak magnitude. Default is0.95, which leaves a headroom of5%*. It is not recommended to go above this value โ ๏ธmaxgain,mโ sets the maximum gain factor. Range1.0to100.0, default10.0. For each input frame the normalizer works out the maximum possible local gain factor โ the biggest gain that won't cause clipping or distortion โ and that's determined by the frame's highest magnitude sample. But it also bounds that frame's max gain by a predetermined global maximum gain factor, specifically so it doesn't go feral with huge gain on "silent" or almost-silent frames ๐ Default max is10.0, and for most inputs that's plenty; usually it is not recommended to increase it. That said, if your input has an extremely low overall volume level, you might need to allow even higher gain factors. But note: the normalizer doesn't just slap a "hard" threshold on it (like cutting off values above the threshold) โ instead a "sigmoid" threshold function gets applied, so gain factors smoothly approach the threshold value but never exceed it. Iconic behaviour honestly ๐targetrms,rโ sets the target RMS. Range0.0to1.0, default0.0โ which means disabled. By default the Dynamic Audio Normalizer does "peak" normalization, meaning each frame's maximum local gain factor is defined (only) by that frame's highest magnitude sample, so samples get amplified as much as possible without exceeding the max signal level, i.e. without clipping. Optionally though, it can also take the frame's root mean square (RMS) into account. 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 staring at the signal's peak magnitude ๐ So by adjusting all frames to a constant RMS value, you get a uniform "perceived loudness" โ slay. If a target RMS value is specified, a frame's local gain factor is defined as the factor that would result in exactly that RMS value. But note: the maximum local gain factor is still restricted by the frame's highest magnitude sample, in order to prevent clipping ๐coupling,nโ enable channels coupling. Enabled by default. Default behaviour: amplify all channels by the same amount, meaning the same gain factor applies to every channel, so the maximum possible gain factor is determined by the "loudest" channel. But some recordings have uneven volume across channels โ one channel might be "quieter" than the other(s) โ and in that case you can use this option to disable the channel coupling ๐ Then the gain factor is determined independently for each channel, depending only on that individual channel's highest magnitude sample. Which lets you harmonize the volume of the different channels. Chef's kiss ๐correctdc,cโ enable DC bias correction. Disabled by default. So, an audio signal (in the time domain) is a sequence of sample values, and in the Dynamic Audio Normalizer those sample values are represented in the-1.0to1.0range, regardless of the original input format. Normally the audio signal (the "waveform") should be centered around the zero point โ meaning if you calculate the mean of all samples in a file, or in a single frame, the result should be0.0or at least very close to it. If there's a significant deviation of the mean from0.0, in either the positive or negative direction, that's called a DC bias or DC offset. Since a DC bias is clearly undesirable, the normalizer offers optional DC bias correction โจ 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 puts those samples back centered around0.0. And to avoid "gaps" at the frame boundaries, the DC correction offset values get interpolated smoothly between neighbouring frames. Smooth like butter ๐งaltboundary,bโ enable alternative boundary mode. Disabled by default. The normalizer looks at a certain neighbourhood around each frame โ the frames before it and the frames after it. But for the "boundary" frames at the very beginning and the very end of the audio file, not all neighbouring frames are available ๐ญ Like, for the first few frames of the file the preceding frames aren't known, and for the last few frames the subsequent frames aren't known. So the question arises: what gain factors do we assume for the missing frames in that "boundary" region? The Dynamic Audio Normalizer implements two modes for this. The default boundary mode assumes a gain factor of exactly1.0for the missing frames, which results in a smooth "fade in" and "fade out" at the beginning and end of the input respectively ๐ธcompress,sโ sets the compress factor. Range0.0to30.0, default0.0. By default the Dynamic Audio Normalizer does not apply "traditional" compression โ signal peaks don't get pruned, so the full dynamic range is retained within each local neighbourhood. But sometimes you want to combine the normalization algorithm with a more "traditional" compression, and that's exactly what this optional compression (thresholding) function is for. 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 โ and you knew this was coming โ the normalizer doesn't just apply a fixed threshold value; the threshold gets adjusted for each individual frame ๐ฆ In general, smaller parameters give stronger compression, and vice versa. Values below3.0are not recommended, because audible distortion may appear ๐threshold,tโ sets the target threshold value. This specifies the lowest permissible magnitude level for the audio input that will be normalized. If an input frame's volume is above this value, the frame gets normalized; otherwise the frame may not be normalized at all. Default is0, which means every input frame gets normalized. This option is mostly useful when you don't want digital noise to get amplified ๐ โโ๏ธchannels,hโ specify which channels to filter. By default, all available channels are filtered.overlap,oโ specify overlap for frames. If set to0(the default), no frame overlapping is done. Using values>0and<1gives you less conservative gain adjustments, kind of like when theframelenoption is set to a smaller value โ and if theframelenoption value is compensated for non-zero overlap, then gain adjustments will be smoother across time compared to the zero overlap case ๐curve,vโ specify the peak mapping curve expression, which gets 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. The expression can contain the following constants:chโ current channel numbersnโ current sample numbernb_channelsโ number of channelstโ timestamp expressed in secondssrโ sample rate
pโ current frame peak value ๐
๐ฌ Commands ๐ฌ
This filter supports the all above options as commands. yes bestie, all of them, go wild ๐ซถ
๐ง earwax ๐ง
Makes audio easier to listen to on headphones. that's it, that's the whole vibe ๐
What it actually does: it adds cues to 44.1kHz stereo (i.e. audio CD format) audio so that when you listen on headphones, the stereo image gets moved from inside your head (which is the standard headphone experience, lowkey cursed) to outside and in front of the listener (which is the standard speaker experience). it's giving "I'm not trapped in your skull anymore" โจ
Ported from SoX. iconic lineage fr fr ๐
๐๏ธ equalizer ๐๏ธ
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 โ and this is the whole point, unlike bandpass and bandreject filters โ that at all other frequencies is unchanged. no cap, everything else stays exactly where it was ๐
So you can build complex equalisation curves by giving this filter several times, each with a different central frequency. stack 'em like bracelets 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. the options are: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. > โ ๏ธ Beware of clipping when using a positive gain. like genuinely, watch it, positive gain will clip on you and it will not be cute ๐ญmix,mโ how much to use the filtered signal 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 it's disabled. Enabling it will normalize magnitude response at DC to 0dB.transform,aโ set transform type of IIR filter. your picks are: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 a high enough value (higher than 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 filter delay will be exactly this many samples when set to a non-zero value.
๐ธ Examples ๐ธ
- 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 ๐ฌ
This filter supports the following commands:
frequency,fโ change equalizer frequency. Syntax for the command is:frequencywidth_type,tโ change equalizer width_type. Syntax for the command is:width_typewidth,wโ change equalizer width. Syntax for the command is:widthgain,gโ change equalizer gain. Syntax for the command is:gainmix,mโ change equalizer mix. Syntax for the command is:mix
๐ extrastereo ๐
Linearly increases the difference between left and right channels, which adds some sort of "live" effect to playback. main character energy for your stereo field โจ
The filter accepts the following options:
mโ sets the difference coefficient (default:2.5).0.0means mono sound (average of both channels), with1.0sound will be unchanged, with-1.0left and right channels will be swapped. yes, swapped. chaos mode, we love her ๐cโ enable clipping. by default is enabled. (so if you want no clipping you gotta turn it off yourself, iykyk)
๐ฌ Commands ๐ฌ
This filter supports the all above options as commands. ๐ซถ
๐ฅ firequalizer ๐ฅ
Apply FIR Equalization using arbitrary frequency response. this one is the overachiever of the EQ filters fr fr 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 to0when 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 ongain_entrycubic_interpolate(f)โ same asgain_interpolate, but smoother โจ
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 is0.01.accuracyโ set filter accuracy in Hz. Lower value means more accurate. Default is5.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. ๐dumpscaleโ set scale fordumpfile. 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.
๐ Examples ๐
- 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 ๐
Apply a flanging effect to the audio. swooshy swoosh, you know the one ๐ฆ
The filter accepts the following options:
delayโ set base delay in milliseconds. Range from0to30. Default value is0.depthโ set added sweep delay in milliseconds. Range from0to10. Default value is2.regenโ set percentage regeneration (delayed signal feedback). Range from-95to95. Default value is0.widthโ set percentage of delayed signal mixed with original. Range from0to100. Default value is71.speedโ set sweeps per second (Hz). Range from0.1to10. Default value is0.5.shapeโ set swept wave shape, can betriangularorsinusoidal. Default value issinusoidal.phaseโ set swept wave percentage-shift for multi channel. Range from0to100. Default value is25.interpโ set delay-line interpolation,linearorquadratic. Default islinear.
๐ซถ haas ๐ซถ
Apply Haas effect to audio.
๐ก 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. so like... mono in, suddenly-it's-everywhere out โจ
The filter accepts the following options:
level_inโ set input level. By default is1, or 0dB.level_outโ set output level. By default is1, or 0dB.side_gainโ set gain applied to side part of signal. By default is1.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 is2.05milliseconds.left_balanceโ set left channel balance. By default is-1.left_gainโ set left channel gain. By default is1.left_phaseโ change left phase. By default is disabled.right_delayโ set right channel delay. By defaults is2.12milliseconds.right_balanceโ set right channel balance. By default is1.right_gainโ set right channel gain. By default is1.right_phaseโ change right phase. By default is enabled.
๐ฟ hdcd ๐ฟ
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 for bits ๐
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
โ ๏ธ 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. like, all that work and then wav just chops it ๐ญ Use something like -acodec pcm_s24le after the filter to get 24-bit PCM output.
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.process_stereoโ processes the stereo channels together as one unit ๐ and iftarget_gaindoesn't match between the channels, it's treated as invalid and the last validtarget_gaingets reused instead. consistency is the vibe.cdt_msโ sets the code detect timer period, in ms โฑ๏ธforce_peโ always extends peaks above -3dBFS, even if PE isn't signaled. no invitation needed, the peaks are getting extended anyway ๐analyze_modeโ replaces the audio with a solid tone and adjusts the amplitude so it signals some specific aspect of the decoding process. the output file can be loaded in an audio editor alongside the original to aid analysis ๐ฌโจ
analyze_mode=pe:force_pe=true can be used to see all samples above the PE level.
the modes are:
0,offโ disabled1,lleโ gain adjustment level at each sample2,peโ samples where peak extend occurs3,cdtโ samples where the code detect timer is active4,tgmโ samples where the target gain does not match between channels
๐ง headphone
okay so this one applies head-related transfer functions (HRTFs) to create virtual loudspeakers all around the listener, for binaural listening through headphones ๐ถ๐ซถ the HRIRs come in through additional streams โ for each channel you need one stereo input stream.
it accepts these options:
mapโ sets the mapping of input streams for 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, and the number of input streams must be not less than the number of channels in the first stream plus one ๐บ๏ธgainโ sets the gain applied to the audio. the value is in dB. default is0.typeโ sets the processing type. can betimeorfreq.timeis processing audio in the time domain, which is slow ๐freqis processing audio in the frequency domain, which is fast โก default isfreq.lfeโ sets a custom gain for LFE channels. the value is in dB. default is0.sizeโ sets the size of the frame, in number of samples, that will be processed at once. default value is1024. allowed range is from1024to96000.hrirโ sets the format of the hrir stream. default value isstereo, the alternative value ismultich. if it's set tostereo, the number of additional streams should be greater or equal to the number of input channels in the first input stream. also, each additional stream should have a stereo number of channels. if it's set tomultich, the number of additional streams should be exactly one โ and the number of input channels of the additional stream should be equal to or greater than twice the number of channels of the first input stream ๐ฆ
๐ Examples
- full example using wav files as coefficients with
amoviefilters for a 7.1 downmix, where eachamoviefilter uses a stereo file with IR coefficients as input. the files give coefficients for each position of the virtual loudspeaker:
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
amoviefilters for a 7.1 downmix, but now inmultichhrir format ๐ง
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
๐ธ highpass
applies a high-pass filter with a 3dB point frequency. the filter can be single-pole, or double-pole (that's the default). it rolls off at 6dB per pole per octave (which is 20dB per pole per decade) ๐
the filter accepts these 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 the filter, inwidth_typeunits. applies only to the double-pole filter. the default is0.707q, and that gives you a Butterworth response ๐งmix,mโ how much of the filtered signal ends up in the output. default is1. range is between0and1.channels,cโ specifies which channels to filter. by default, all available channels are filtered.normalize,nโ normalizes the biquad coefficients. by default it's disabled. enabling it will normalize the magnitude response at DC to 0dB.transform,aโ sets the transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ 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,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 becomes linear phase โ otherwise, if it's not big enough, it will just produce nasty artifacts ๐ญโ ๏ธ
note that the filter delay will be exactly this many samples when set to a non-zero value.
โจ๏ธ Commands
this filter supports these commands, so you can change stuff live:
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"
๐ join
joins multiple input streams into one multi-channel stream. it literally just brings everybody together ๐ซถ
it accepts these parameters:
inputsโ the number of input streams. defaults to2.channel_layoutโ the desired output channel layout. defaults tostereo.mapโ maps channels from inputs to the output. the argument is a'|'-separated list of mappings, each one in theinput_idx.in_channel-out_channelform.input_idxis the 0-based index of the input stream.in_channelcan be either the name of the input channel (likeFLfor front left) or its index in the specified input stream.out_channelis the name of the output channel.
if you don't specify the mappings explicitly, the filter will attempt to guess them โ it does that by first trying to find an unused matching input channel, and if that fails it just picks the first unused input channel ๐
โจ Examples
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
๐งฉ ladspa
loads a LADSPA (Linux Audio Developer's Simple Plugin API) plugin โ yes that's the whole name, they really committed to the acronym ๐ญ
to enable compilation of this filter you need to configure FFmpeg with --enable-ladspa ๐ ๏ธ
file,fโ specifies the name of the LADSPA plugin library to load. if the environment variableLADSPA_PATHis defined, the LADSPA plugin is searched for in each one of the directories specified by the colon-separated list inLADSPA_PATH; otherwise it looks 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 ๐controls,cโ sets the'|'-separated list of controls, which are zero or more floating point values that determine the behavior of the loaded plugin (things like delay, threshold or gain). controls need to be defined using this syntax:c0=value0|c1=value1|c2=value2|..., where valuei is the value set on the i-th control. alternatively they can also be defined using this syntax:value0|value1|value2|..., where valuei is the value set on the i-th control. and ifcontrolsis set to"help", all available controls and their valid ranges get printed ๐sample_rate,sโ specifies the sample rate, defaults to44100. only used if the plugin has zero inputs.nb_samples,nโ sets the number of samples per channel per each 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 greater than the specified duration, since the generated audio is always cut at the end of a complete frame. if not specified, or if the expressed duration is negative, the audio is supposed to be generated forever โพ๏ธ only used if the plugin has zero inputs.latency,lโ enables latency compensation. by default it's disabled. only used if the plugin has inputs.
๐ Examples
- 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) ๐:
ladspa=file=tap_reverb:tap_reverb
- generate white noise, with 0.2 amplitude:
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's
"SWH Plugins"collection:
ladspa=fast_lookahead_limiter_1913:fastLookaheadLimiter:20|0|2
- attenuate low frequencies using the Multiband EQ from Steve Harris's
"SWH Plugins"collection:
ladspa=mbeq_1197:mbeq:-24|-24|-24|0|0|0|0|0|0|0|0|0|0|0|0
- reduce stereo image using
"Narrower"from the"C* Audio Plugin Suite"(CAPS) library: - ๐ฆ and the last one of the previous batch,
ladspa=caps:Narrower, still living its best life:
ladspa=caps:Narrower
- ๐ Another white noise moment, this time pulling from the "C* Audio Plugin Suite" (CAPS) library:
ladspa=caps:White:.2
- ๐ธ Some fractal noise, also courtesy of "C* Audio Plugin Suite" (CAPS):
ladspa=caps:Fractal:c=c1=1
- ๐ Dynamic volume normalization using the "VLevel" plugin:
ladspa=vlevel-ladspa:vlevel_mono
๐ Commands
Bestie, this filter takes commands too โ here's the tea:
cNโ tweak the N-th control value. And if the value you hand over isn't valid? It just gets ignored, no cap, and the previous one stays exactly where it was. ๐
๐ง loudnorm
EBU R128 loudness normalization, and yes she does both dynamic and linear normalization modes. She's got support for single pass (livestreams, files) and double pass (files) โ versatile icon. This algorithm can target IL, LRA, and maximum true peak. Heads up: in dynamic mode, to accurately detect true peaks, the audio stream gets upsampled to 192 kHz, so use the -ar option or the aresample filter to explicitly set an output sample rate. โจ
The filter accepts the following options:
I,iโ set the integrated loudness target. Range is-70.0--5.0, default is-24.0.LRA,lraโ set the loudness range target. Range is1.0-50.0, default is7.0.TP,tpโ set the maximum true peak. Range is-9.0-+0.0, default is-2.0.measured_I,measured_iโ measured IL of the input file. Range is-99.0-+0.0.measured_LRA,measured_lraโ measured LRA of the input file. Range is0.0-99.0.measured_TP,measured_tpโ measured true peak of the input file. Range is-99.0-+99.0.measured_threshโ measured threshold of the input file. Range is-99.0-+0.0.offsetโ set the offset gain. The gain gets applied before the true-peak limiter. Range is-99.0-+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 that exceeds the target TP. If any of those 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 meant for playback on a stereo system, its EBU R128 measurement will be perceptually incorrect, which is giving broken. If set totrue, this option compensates for that effect. Multi-channel input files are not affected by this option at all. Options aretrueorfalse, default isfalse.print_formatโ set the 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.
๐ lowpass
Apply a low-pass filter with 3dB point frequency. The filter can be either single-pole or double-pole (double-pole is the default, obvi). It rolls off at 6dB per pole per octave (20dB per pole per decade). Slay.
The filter accepts the following options:
frequency,fโ set frequency in Hz. Default is500.poles,pโ set number of poles. Default is2.width_type,tโ set the method to specify band-width of the filter:hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ specify the band-width of a filter inwidth_typeunits. Applies only to the double-pole filter. Default is0.707q, which 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 get filtered.normalize,nโ normalize biquad coefficients, disabled by default. Enabling it will normalize magnitude response at DC to0dB.transform,aโ set transform type of the IIR filter:didiitditdiilattsvfzdf
precision,rโ set 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 set the block size used for reverse IIR processing. If you set this 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'll just produce nasty artifacts. ๐ Note that the filter delay will be exactly this many samples when set to a non-zero value.
๐ Examples
- Lowpass only the LFE channel โ and if LFE isn't present, it does absolutely nothing:
lowpass=c=LFE
๐ Commands
This filter supports the following commands:
frequency,fโ change lowpass frequency. Syntax for the command is:frequencywidth_type,tโ change lowpass width_type. Syntax for the command is:width_typewidth,wโ change lowpass width. Syntax for the command is:widthmix,mโ change lowpass mix. Syntax for the command is:mix
๐ง lv2
Load an LV2 (LADSPA Version 2) plugin. 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':'.controls,cโ set the'|'separated list of controls, which are zero or more floating point values that determine the behavior of the loaded plugin (think delay, threshold, or gain). Ifcontrolsis set tohelp, all available controls and their valid ranges get printed. ๐ซถsample_rate,sโ specify the sample rate, defaults to44100. 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 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.
๐ Examples
- Apply the bass enhancer plugin from Calf:
lv2=p=http\\\\://calf.sourceforge.net/plugins/BassEnhancer:c=amount=2
- Apply the vinyl plugin from Calf:
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
๐ Commands
This filter supports all options that are exported by the plugin as commands. iykyk.
๐๏ธ mcompand
Multiband compress or expand the audio's dynamic range. The input audio gets divided into bands using 4th order Linkwitz-Riley IIRs โ this is akin to the crossover of a loudspeaker, and it results in a flat frequency response when there's no compander action happening. โจ
It accepts the following parameters:
argsโ the option syntax is:attack,decay,[attack,decay..] soft-knee points crossover_frequency [delay [initial_volume [gain]]] | attack,decay ...โ for an explanation of each item, refer to thecompandfilter documentation.
๐๏ธ pan
Mix channels with specific gain levels. The filter accepts the output channel layout followed by a set of channel definitions. She's also designed to efficiently remap the channels of an audio stream โ main character energy, honestly.
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 โ pick a lane, bestie. ๐
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. Obsessed with a smart little optimization.
๐ Mixing examples
Say you wanna 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-channel 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
Ngl,ffmpegintegrates a default down-mix (and up-mix) system that should be preferred (see the-acoption) unless you have very specific needs. So don't reinvent the wheel for no reason. ๐ซถ
๐ธ Remapping examples
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. Ate. ๐ฅ
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 the 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"
๐ต replaygain
ReplayGain scanner filter. This filter takes an audio stream as an input and outputs it unchanged โ literally zero notes, she just observes. At the end of filtering it displays track_gain and track_peak. ๐
The filter accepts the following exported read-only options:
track_gainโ exported track gain in dB at end of stream.track_peakโ exported track peak at end of stream.
๐ resample
Convert the audio sample format, sample rate, and channel layout. It is not meant to be used directly. That's it, that's the whole vibe โ she's an internal icon, not a public one. ๐
๐งโ๐ค rubberband
Apply time-stretching and pitch-shifting with librubberband. To enable compilation of this filter, you need to configure FFmpeg with --enable-librubberband.
The filter accepts the following options:
tempoโ sets the tempo scale factor ๐ต like, how fast the whole thing grooves.pitchโ sets the pitch scale factor ๐ค up or down, your call bestie.transientsโ picks the transients detector. The possible values are literally:crispmixedsmooth
detectorโ picks the detector. Possible values, periodt:compoundpercussivesoft
phaseโ sets phase. Possible values are:laminarindependent
windowโ sets the processing window size. Possible values:standardshortlong
smoothingโ sets smoothing. Possible values:offon
formantโ turns formant preservation on when you're shift-pitching ๐ . Possible values are:shiftedpreserved
pitchqโ sets pitch quality. Possible values:qualityspeedconsistency
channelsโ sets channels. Possible values:aparttogether
๐๏ธ Commands
This filter supports the following commands:
tempoโ changes the filter tempo scale factor. Syntax for the command is :tempopitchโ changes the filter pitch scale factor. Syntax for the command is :pitch
sidechaincompress ๐ซถ
Okay so this filter is literally a normal compressor but with main-character energy: it can compress the detected signal using a second input signal. It needs two input streams and hands back one output stream. The first input stream gets processed depending on the second stream's signal, and then that filtered signal can go hang out with other filters in later stages of processing. Peep pan and amerge if you wanna see the family.
The filter accepts the following options:
level_inโ sets the input gain. Default is1. Range is between0.015625and64.modeโ sets 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 it's0.125. Range is between0.00097563and1.ratioโ sets a ratio about which the signal is reduced. Like,1:2means that if the level raised 4dB above the threshold, it'll only be 2dB above after the reduction. Default is2. Range is between1and20.attackโ the amount of milliseconds the signal has to rise above the threshold before gain reduction starts. Default is20. Range is between0.01and2000.releaseโ the amount of milliseconds the signal has to fall below the threshold before reduction is decreased again. Default is250. Range is between0.01and9000.makeupโ sets the amount by how much signal will be amplified after processing. Default is1. Range is from1to64.kneeโ curves the sharp knee around the threshold so you enter gain reduction more softly ๐ธ. Default is2.82843. Range is between1and8.linkโ chooses 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 sets the sidechain gain. Default is1. Range is between0.015625and64.mixโ how much to use the compressed signal in the output. Default is1. Range is between0and1.
Commands
This filter supports all the above options as commands. no cap ๐
Examples
- Full ffmpeg example taking 2 audio inputs, 1st input to be compressed depending on the signal of 2nd input, and later the compressed signal to be merged with the 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"
sidechaingate ๐ช
A sidechain gate acts like a normal (wideband) gate but it's got 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. Like, for example: if you cut all the 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're able to reduce the resonation of a natural drum or remove "rumbling" of muted strokes from a heavily distorted guitar ๐ฅ. 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 sets the input level before filtering. Default is1. Allowed range is from0.015625to64.modeโ sets 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 the dynamic range in the upward direction. Otherwise, in case of"downward", lower parts of the signal will be reduced.rangeโ 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.thresholdโ if a signal rises above this level, the gain reduction is released. Default is0.125. Allowed range is from0to1.ratioโ sets a ratio about which the signal is reduced. Default is2. Allowed range is from1to9000.attackโ the amount of milliseconds the signal has to rise above the threshold before gain reduction stops. Default is20milliseconds. Allowed range is from0.01to9000.releaseโ the 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 sets the amount of amplification of the signal after processing. Default is1. Allowed range is from1to64.kneeโ curves the sharp knee around the threshold so you enter gain reduction more softly โจ. Default is2.828427125. Allowed range is from1to8.detectionโ chooses if the exact signal should be taken for detection or an RMS-like one. Default isrms. Can bepeakorrms.linkโ chooses if the average level between all channels or the louder channel affects the reduction. Default isaverage. Can beaverageormaximum.level_scโ sets the sidechain gain. Default is1. Range is from0.015625to64.
Commands
This filter supports all the above options as commands. yup, all of them ๐ซถ
silencedetect ๐คซ
Detects silence in an audio stream. Lowkey iconic for finding dead air.
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.
The filter accepts the following options:
noise,nโ sets the noise tolerance. Can be specified in dB (in case"dB"is appended to the specified value) or as an amplitude ratio. Default is-60dB, or0.001.duration,dโ sets the 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 it's 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 -
silenceremove โ๏ธ
Removes silence from the beginning, middle or end of the audio. It's giving cleanup era ๐งนโจ
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 noises 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 as an amplitude ratio. Default value is0.start_silenceโ specify the 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, ngl.stop_periodsโ sets the count for trimming silence from the end of the 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 ๐ซ . 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.
okay so continuing the silenceremove optionsโthese are the ones that control how the tail end and silence detection behave, and honestly theyโre kind of the main characters for trimming, fr fr. ๐
stop_thresholdโ this is literally the same asstart_thresholdbut for trimming silence from the end of the audio. You can give it in dB (if"dB"is appended to the value) or as an amplitude ratio. Default value is0. ๐stop_silenceโ sets the max duration of silence at the end that will be kept after trimming. Default is0, which is equal to trimming all samples detected as silence. no cap, thatโs the full chop. โจstop_modeโ sets the mode for detecting the start of silence after the start of multi-channel audio. Can beanyorall. Default isall. Withany, any sample from any channel detected as silence will trigger start of silence trimming after start of audio streamโlimited usage, bestie. Withall, only if every sample from every channel is detected as silence will trigger start of silence trimming after start of audio stream. Itโs giving strict versus chaotic. ๐ญdetectionโ sets how silence is detected. The options are:avgโ mean of absolute values of samples in moving window.rmsโ root squared mean of absolute values of samples in moving window.peakโ maximum of absolute values of samples in moving window.medianโ median of absolute values of samples in moving window.ptpโ absolute of max peak to min peak difference of samples in moving window.devโ standard deviation of values of samples in moving window.
Default value is "rms". ๐ฆ
windowโ sets duration in number of seconds used to calculate size of window in number of samples for detecting silence. Using0will effectively disable any windowing and use only single sample per channel for silence detection. In that case it may be needed to also setstart_silenceand/orstop_silenceto nonzero values with alsostart_durationand/orstop_durationto nonzero values. Default value is0.02. Allowed range is from0to10. Lowkey crucial, highkey underrated. ๐ธtimestampโ sets processing mode of every audio frame output timestamp. The modes are:writeโ full timestamps rewrite, keep only the start time for the first output frame.copyโ non-dropped frames are left with same timestamp as input audio frame.
Default value is "write". ๐
๐ธ Examples ๐ธ
- The following example shows how this filter can be used to start a recording that does not contain the delay at the start which usually occurs between pressing the record button and the start of the performance:
silenceremove=start_periods=1:start_duration=5:start_threshold=0.02
- Trim all silence encountered from beginning to end where there is more than 1 second of silence in audio:
silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-90dB
- Trim all digital silence samples, using peak detection, from beginning to end where there is more than 0 samples of digital silence in audio and digital silence is detected in all channels at same positions in stream:
silenceremove=window=0:detection=peak:stop_mode=all:start_mode=all:stop_periods=-1:stop_threshold=0
- Trim every 2nd encountered silence period from beginning to end where there is more than 1 second of silence per silence period in audio:
silenceremove=stop_periods=-2:stop_duration=1:stop_threshold=-90dB
- Similar as above, but keep 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
- Similar as above, but keep maximum of 1.5 seconds of silence from start of 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
๐ฌ Commands ๐ฌ
This filter supports some above options as commands. yes bestie, runtime tweaking is on the menu. ๐ซถ
๐ง sofalizer ๐ง
SOFAlizer uses head-related transfer functions (HRTFs) to create virtual loudspeakers around the user for binaural listening via headphones (audio formats up to 9 channels supported). The HRTFs are stored in SOFA files (see http://www.sofacoustics.org/ for a database). SOFAlizer is developed at the Acoustics Research Institute (ARI) of the Austrian Academy of Sciences. iconic academic binaural behavior, honestly. ๐
To enable compilation of this filter you need to configure FFmpeg with --enable-libmysofa. slay, dependency check. โจ
The filter accepts the following options:
sofaโ set the SOFA file used for rendering. ๐gainโ set gain applied to audio. Value is in dB. Default is0.rotationโ set rotation of virtual loudspeakers in deg. Default is0.elevationโ set elevation of virtual speakers in deg. Default is0.radiusโ set distance in meters between loudspeakers and the listener with near-field HRTFs. Default is1.typeโ set processing type. Can betimeorfreq.timeis processing audio in time domain which is slow.freqis processing audio in frequency domain which is fast. Default isfreq. chose speed, periodt. ๐ฅspeakersโ set custom positions of virtual loudspeakers. Syntax for this option is:<CH> <AZIM> <ELEV>[|<CH> <AZIM> <ELEV>|...]. Each virtual loudspeaker is described with short channel name following with azimuth and elevation in degrees. Each virtual loudspeaker description is separated by'|'. For example to override front left and front right channel positions use:'speakers=FL 45 15|FR 345 15'. Descriptions with unrecognised channel names are ignored. iykyk, channel placement is a vibe. ๐ฆlfegainโ set custom gain for LFE channels. Value is in dB. Default is0.framesizeโ set custom frame size in number of samples. Default is1024. Allowed range is from1024to96000. Only used if optiontypeis set tofreq.normalizeโ should all IRs be normalized upon importing SOFA file. By default is enabled.interpolateโ should nearest IRs be interpolated with neighbor IRs if exact position does not match. By default is disabled.minphaseโ minphase all IRs upon loading of SOFA file. By default is disabled.anglestepโ set neighbor search angle step. Only used if optioninterpolateis enabled.radstepโ set neighbor search radius step. Only used if optioninterpolateis enabled.
๐ Examples ๐
- Using ClubFritz6 sofa file:
sofalizer=sofa=/path/to/ClubFritz6.sofa:type=freq:radius=1
- Using ClubFritz12 sofa file and bigger radius with small rotation:
sofalizer=sofa=/path/to/ClubFritz12.sofa:type=freq:radius=2:rotation=5
- Similar as above but with custom speaker positions for front left, front right, back left and back right and also with custom gain:
"sofalizer=sofa=/path/to/ClubFritz6.sofa:type=freq:radius=2:speakers=FL 45|FR 315|BL 135|BR 225:gain=28"
๐ฃ๏ธ speechnorm ๐ฃ๏ธ
Speech Normalizer. This filter expands or compresses each half-cycle of audio samples (local set of samples all above or all below zero and between two nearest zero crossings) depending on threshold value, so audio reaches target peak value under conditions controlled by below options. itโs giving audio glow-up, but make it math. ๐
The filter accepts the following options:
peak,pโ set the expansion target peak value. This specifies the highest allowed absolute amplitude level for the normalized audio input. Default value is0.95. Allowed range is from0.0to1.0.expansion,eโ set the maximum expansion factor. Allowed range is from1.0to50.0. Default value is2.0. This option controls maximum local half-cycle of samples expansion. The maximum expansion would be such that local peak value reaches target peak value but never to surpass it and that ratio between new and previous peak value does not surpass this option value. no overshoot, bestie. โจcompression,cโ set the maximum compression factor. Allowed range is from1.0to50.0. Default value is2.0. This option controls maximum local half-cycle of samples compression. This option is used only ifthresholdoption is set to value greater than0.0, then in such cases when local peak is lower or same as value set by threshold all samples belonging to that peak's half-cycle will be compressed by current compression factor.threshold,tโ set the threshold value. Default value is0.0. Allowed range is from0.0to1.0. This option specifies which half-cycles of samples will be compressed and which will be expanded. Any half-cycle samples with their local peak value below or same as this option value will be compressed by current compression factor, otherwise, if greater than threshold value they will be expanded with expansion factor so that it could reach peak target value but never surpass it. the sorting hat of half-cycles, lowkey. ๐raise,rโ set the expansion raising amount per each half-cycle of samples. Default value is0.001. Allowed range is from0.0to1.0. This controls how fast expansion factor is raised per each new half-cycle until it reachesexpansionvalue. Setting this options too high may lead to distortions. be careful, gorgeous. ๐ญfall,fโ set the compression raising amount per each half-cycle of samples. Default value is0.001. Allowed range is from0.0to1.0. This controls how fast compression factor is raised per each new half-cycle until it reachescompressionvalue.channels,hโ specify which channels to filter, by default all available channels are filtered.invert,iโ enable inverted filtering, by default is disabled. This inverts interpretation ofthresholdoption. When enabled any half-cycle of samples with their local peak value below or same asthresholdoption will be expanded otherwise it will be compressed.link,lโ link channels when calculating gain applied to each filtered channel sample, by default is disabled. When disabled each filtered channel gain calculation is independent, otherwise when this option is enabled the minimum of all possible gains for each filtered channel is used.rms,mโ set the expansion target RMS value. This specifies the highest allowed RMS level for the normalized audio input. Default value is0.0, thus disabled. Allowed range is from0.0to1.0.
๐ฌ Commands ๐ฌ
This filter supports all the above options as commands. runtime control, we love to see it. ๐ซถ
๐ Examples ๐
- 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 literally a whole toolbox for stereo signals โ it converts M/S stereo recordings to L/R while letting you control the parameters, and it can also spread the stereo image of a master track. It's giving "Swiss army knife but make it audio." ๐
It accepts these options:
level_inโ input level before filtering, for both channels. Default is1. Allowed range is0.015625to64.level_outโ output level after filtering, for both channels. Default is1. Allowed range is0.015625to64.balance_inโ input balance between both channels. Default is0. Allowed range is-1to1.balance_outโ output balance between both channels. Default is0. Allowed range is-1to1.softclipโ enable softclipping. Gives you analog distortion instead of that harsh digital 0dB clipping. Disabled by default.mutelโ mute the left channel. Disabled by default.muterโ mute the right channel. Disabled by default.phaselโ flip the phase of the left channel. Disabled by default.phaserโ flip the phase of the right channel. Disabled by default.modeโ set the stereo mode. Available values:lr>lrโ Left/Right to Left/Right, this is the default.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 level of the side signal. Default is1. Allowed range is0.015625to64.sbalโ balance of the side signal. Default is0. Allowed range is-1to1.mlevโ level of the middle signal. Default is1. Allowed range is0.015625to64.mpanโ middle signal pan. Default is0. Allowed range is-1to1.baseโ stereo base between mono and inversed channels. Default is0. Allowed range is-1to1.delayโ delay in milliseconds, i.e. how much to delay left from right channel and vice versa. Default is0. Allowed range is-20to20.sclevelโ S/C level. Default is1. Allowed range is1to100.phaseโ the stereo phase in degrees. Default is0. Allowed range is0to360.bmode_in,bmode_outโ set the balance mode for thebalance_in/balance_outoptions. Can be one of: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
This filter supports all of the above options as commands. Iconic. ๐
Examples
- 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 common to both channels, and by delaying the left signal into the right and vice versa โ thereby widening the stereo effect. It just makes everything feel bigger, no cap. โจ
It accepts these options:
delayโ time in milliseconds of the delay of left signal into right and vice versa. Default is20milliseconds.feedbackโ amount of gain in the delayed signal into right and vice versa. Gives a delay effect of the left signal in the right output and vice versa, which is what gives you that widening effect. Default is0.3.crossfeedโ cross feed of left into right with inverted phase. Helps suppress the mono. If the value is1it will cancel all the signal common to both channels. Default is0.3.drymixโ level of input signal of the original channel. Default is0.8.
Commands
This filter supports all the above options except delay as commands. (Yes, delay is the one that doesn't get to come to the party. ๐ญ)
superequalizer ๐๏ธ
Apply an 18 band equalizer. Eighteen. Bands. Obsessed.
The filter accepts these options:
1bโ set 65Hz band gain.2bโ set 92Hz band gain.3bโ set 131Hz band gain.4bโ set 185Hz band gain.5bโ set 262Hz band gain.6bโ set 370Hz band gain.7bโ set 523Hz band gain.8bโ set 740Hz band gain.9bโ set 1047Hz band gain.10bโ set 1480Hz band gain.11bโ set 2093Hz band gain.12bโ set 2960Hz band gain.13bโ set 4186Hz band gain.14bโ set 5920Hz band gain.15bโ set 8372Hz band gain.16bโ set 11840Hz band gain.17bโ set 16744Hz band gain.18bโ set 20000Hz band gain.
surround ๐
Apply the audio surround upmix filter. This one lets you produce multichannel output from an audio stream โ glow-up for your two-channel audio, fr fr. ๐ฅ
The filter accepts these options:
chl_outโ set 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 set the input channel layout. By default this isstereo. See the Channel Layout section in theffmpeg-utils(1)manual for the required syntax.level_inโ set the input volume level. By default this is1.level_outโ set 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 set the LFE low cut off frequency. By default this is128Hz.lfe_highโ set the LFE high cut off frequency. By default this is256Hz.lfe_modeโ set 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 set the temporal smoothness strength, used to gradually change factors when transforming stereo sound in time. Allowed range is0.0to1.0. Useful to improve output quality withfocusoption values greater than0.0. Default is0.0. Only values inside this range and without edges are effective.angleโ set the angle of the stereo surround transform. Allowed range is0to360. Default is90.focusโ set the focus of the stereo surround transform. Allowed range is-1to1. Default is0.fc_inโ set the front center input volume. By default this is1.fc_outโ set the front center output volume. By default this is1.fl_inโ set the front left input volume. By default this is1.fl_outโ set the front left output volume. By default this is1.fr_inโ set the front right input volume. By default this is1.fr_outโ set the front right output volume. By default this is1.sl_inโ set the side left input volume. By default this is1.sl_outโ set the side left output volume. By default this is1.sr_inโ set the side right input volume. By default this is1.sr_outโ set the side right output volume. By default this is1.bl_inโ set the back left input volume. By default this is1.bl_outโ set the back left output volume. By default this is1.br_inโ set the back right input volume. By default this is1.br_outโ set the back right output volume. By default this is1.bc_inโ set the back center input volume. By default this is1.bc_outโ set the back center output volume. By default this is1.lfe_inโ set the LFE input volume. By default this is1.lfe_outโ set the LFE output volume. By default this is1.allxโ set spread usage of the stereo image across the X axis, for all channels. Allowed range is-1to15. By default this value is negative-1, and thus unused.allyโ set spread usage of the stereo image across the Y axis, for all channels. Allowed range is-1to15. By default this value is negative-1, and thus unused.fcx,flx,frx,blx,brx,slx,srx,bcxโ set spread usage of the stereo image across the X axis for each channel. Allowed range is0.06to15. By default this value is0.5.fcy,fly,fry,bly,bry,sly,sry,bcyโ set spread usage of the stereo image across the Y axis for each channel. Allowed range is0.06to15. By default this value is0.5.win_sizeโ set the window size. Allowed range is1024to65536. Default size is4096.win_funcโ set the window function. It accepts the following values:rectbartletthann,hanninghammingblackmanwelchflattopbharrisbnuttallbhannsinenuttalllanczosgausstukeydolphcauchyparzenpoissonbohmankaiser
Default is "hann".
overlapโ set the window overlap. If set to1, the recommended overlap for the selected window function will be picked. Default is0.5.
tiltshelf ๐
Boost or cut the lower frequencies and cut or boost 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). It's giving "the tone knob on your dad's stereo, but make it precision." ๐
The filter accepts these options:
gain,gโ give the gain at0Hz. Its useful range is about-20(for a large cut) to+20(for a large boost). Beware of clipping when using a positive gain.frequency,fโ set 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 is3000Hz.width_type,tโ set the method to specify the band-width of the filter.hโ Hzqโ Q-Factoroโ octavesโ slopekโ kHz
width,wโ determine how steep the filter's shelf transition is.poles,pโ set the number of poles. Default is2.mix,mโ how much to use the filtered signal 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 how precise the filtering math gets to be ๐ pick your sample-format vibe:autoโ let it pick the sample format automatically, based on the surround filters โจs16โ always signed 16-bits32โ always signed 32-bitf32โ always float 32-bitf64โ always float 64-bit
block_size,bโ sets the block size used for reverse IIR processing. If you set this high enough (higher than the impulse response length truncated when it reaches near-zero values) the filtering becomes linear phase โ otherwise, if it's not big enough, it just produces nasty artifacts. ๐ญ
Heads up bestie: when this is set to a non-zero value, the filter delay will be exactly this many samples. No cap.
๐ Commands
This filter supports some options as commands. ๐ซถ
๐๏ธ treble, highshelf
Boost or cut 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. It's also known as shelving equalisation (EQ). Iconic behavior honestly ๐
The filter accepts the following options:
gain,gโ gives the gain at whichever is the lower of ~22 kHz and the Nyquist frequency. Its useful range is about -20 (big cut) to +20 (big boost). โ ๏ธ Beware of clipping when you use a positive gain, fr fr.frequency,fโ sets the filter's central frequency, so you can extend or reduce the frequency range being boosted or cut. Default value is3000Hz.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. ๐ชpoles,pโ sets the number of poles. Default is2.mix,mโ how much of the filtered signal goes into the output. Default is1. Range is between0and1.channels,cโ specifies which channels to filter; by default all available channels get filtered. ๐normalize,nโ normalizes the biquad coefficients; by default this is disabled. Enabling it normalizes 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 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,bโ 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 becomes linear phase; if it's not big enough it just makes nasty artifacts. ๐ญ
Note that the filter delay will be exactly this many samples when it's set to a non-zero value.
๐ Commands
This filter supports the following commands:
frequency,fโ change the treble frequency. Syntax for the command is:"frequency"width_type,tโ change the treblewidth_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"
๐ tremolo
Sinusoidal amplitude modulation. Wiggle wiggle ๐ฆ
The filter accepts the following options:
fโ modulation frequency in Hertz. Modulation frequencies in the subharmonic range (20Hz or lower) give you a tremolo effect. You can also use this filter as a ring modulator by specifying a modulation frequency higher than20Hz. 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.
๐ vibrato
Sinusoidal phase modulation. Same energy, different flavor โจ
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.
๐ virtualbass
Applies the audio Virtual Bass filter. Bass go brrr ๐
This filter accepts stereo input and produces stereo with LFE (2.1) channels as 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, just as they were in the stereo input โ no notes taken, no notes added ๐ซถ
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.
๐๏ธ volume
Adjusts the input audio volume. The main character of audio filters, honestly ๐
It accepts the following parameters:
volumeโ sets the audio volume expression.
Output values are clipped to the maximum value.
The output audio volume is given by the relation:
<output_volume> = <volume> * <input_volume>
The default value for volume is "1.0".
precisionโ 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 the input sample format toU8,S16, andS32.floatโ 32-bit floating-point; this limits the input sample format toFLT. (default)doubleโ 64-bit floating-point; this limits the input sample format toDBL.
replaygainโ chooses the behaviour when it encounters 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_preampโ pre-amplification gain in dB to apply to the selected replaygain gain.
Default value for replaygain_preamp is 0.0.
replaygain_noclipโ prevents clipping by limiting the gain applied.
Default value for replaygain_noclip is 1.
evalโ 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 โ ๏ธptsโ frame PTSsample_rateโ sample ratestartptsโ PTS at start of streamstarttโ time at start of streamtโ frame timetbโ timestamp timebasevolumeโ last set volume value
Okay important: whenevalis set toonce, only thesample_rateandtbvariables are available โ all the other variables will evaluate toNAN. ๐
๐ Commands
This filter supports the following commands:
volumeโ modifies the volume expression. The command accepts the same syntax as the corresponding option.
If the specified expression isn't valid, it's kept at its current value.
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, like this:
volume=0.5
- Increase input audio power by 6 decibels using fixed-point precision:
volume=volume=6dB:precision=fixed
- Fade volume after time
10with an annihilation period of5seconds:
volume='if(lt(t,10),1,max(1-(t-10)/5,0))':eval=frame
๐ volumedetect
Detects the volume of the input video. Detective mode activated ๐ต๏ธโโ๏ธ
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 get printed in the log when the end of the input stream is reached.
In particular it will show the mean volume (root mean square), the 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. ๐
๐ Examples
Here's 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
-27dB, or 10^-2.7. - The largest sample is at
-4dB, or more precisely between-4dB and-5dB. - There are
6samples at-4dB,62at-5dB,286at-6dB, etc.
In other words, raising the volume by +4 dB doesn't cause any clipping, raising it by +5 dB causes clipping for 6 samples, etc. Maths, but make it audio ๐
๐ฃ๏ธ whisper
Runs automatic speech recognition using OpenAI's Whisper model. Speech-to-text but make it ffmpeg โจ
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). โ ๏ธlanguageโ the language to use for transcription ('auto'for auto-detect). Default value:"auto"queueโ the max size that gets queued into the filter before whisper actually processes the audio. Small value = the stream gets processed more often, but the transcription quality drops and the CPU bill goes up. Big value (like10-20s) = more accurate results using less CPU (same as using thewhisper-clitool), but the transcription latency goes up, so it's not useful for real-time streams. Lowkey consider pairing this with thevad_modeloption and a large queue value. Default value:"3"use_gpuโ whether GPU support should be enabled. Default value:"true"โจgpu_deviceโ the GPU device index to use. Default value:"0"destinationโ if set, the transcription output gets sent to the specified file or URL (use one of the FFmpeg AVIO protocols); otherwise the output is just logged as info messages. The output also gets set in the"lavfi.whisper.text"frame metadata. Heads up: if the destination is a file and it already exists, it will be overwritten ๐ Default value: none.formatโ 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 set to a value greater than0, transcription segments get split so they don't exceed this length. Super useful for generating subtitles with shorter lines. Default value:"0"vad_modelโ path to the VAD model file. If set, the filter loads an additional voice activity detection module (https://github.com/snakers4/silero-vad) which is used to fragment the audio queue; use this option by setting a valid path obtained from the whisper.cpp repository (e.g."../whisper.cpp/models/ggml-silero-v5.1.2.bin") and bump thequeueparameter up to a higher value (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"
โจ Examples โจ
- Bestie, run a transcription and generate an srt file ๐
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 yeet the output in JSON format to an HTTP service ๐ฆ
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 ๐ค (this one's giving main character energy ngl)
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 -
๐ง AUDIO SOURCES ๐ง
Okay so below is the rundown of all the audio sources that currently exist. Slay.
abuffer
Buffers audio frames and makes them available to the filter chain. ๐
This source is mainly intended for programmatic use, specifically through the interface defined in libavfilter/buffersrc.h.
It accepts these parameters:
time_baseโ the timebase that gets used for timestamps of submitted frames. It has to be either a floating-point number or in numerator/denominator form.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 corresponding integer representation from theenum AVSampleFormatinlibavutil/samplefmt.h.channel_layoutโ the channel layout of the incoming audio buffers. Either a channel layout name fromchannel_layout_mapinlibavutil/channel_layout.c, or its corresponding integer representation from theAV_CH_LAYOUT_*macros inlibavutil/channel_layout.h.channelsโ the number of channels of the incoming audio buffers. If bothchannelsandchannel_layoutare specified, then they must be consistent (no fighting, besties ๐ซถ).
Examples
abuffer=sample_rate=44100:sample_fmt=s16p:channel_layout=stereo
will instruct the source to accept planar 16bit signed stereo at 44100Hz. And since the sample format named "s16p" corresponds to the number 6 and the "stereo" channel layout corresponds to the value 0x3, this is literally equivalent to:
abuffer=sample_rate=44100:sample_fmt=6:channel_layout=0x3
aevalsrc
Generates an audio signal specified by an expression. โจ
This source accepts one or more expressions as input (one for each channel), which get evaluated and used to generate a corresponding audio signal.
This source accepts these options:
exprsโ set the'|'-separated expressions list for each separate channel. In case thechannel_layoutoption is not specified, the selected channel layout depends on the number of provided expressions. Otherwise the last specified expression gets applied to the remaining output channels.channel_layout,cโ set the channel layout. The number of channels in the specified layout must equal the number of specified expressions.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 it's not specified, or the expressed duration is negative, the audio is supposed to be generated forever. โพ๏ธ
nb_samples,nโ set the number of samples per channel per each output frame, default is1024.sample_rate,sโ specify the sample rate, default is44100.
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 ๐คซ
aevalsrc=0
- Generate a sin signal with frequency of
440 Hz, set sample rate to8000 Hz
aevalsrc="sin(440*2*PI*t):s=8000"
- Generate a two channels signal, and 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 (the vibe of a broken TV, iconic)
aevalsrc="-2+random(0)"
- Generate an amplitude modulated signal
aevalsrc="sin(10*2*PI*t)*sin(880*2*PI*t)"
- Generate
2.5 Hzbinaural beats on a360 Hzcarrier ๐
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.
The resulting stream can be used with the afir filter to filter the audio signal.
The filter accepts these options:
delay,dโ set the fractional delay. Default is0.sample_rate,rโ set the sample rate, default is44100.nb_samples,nโ set the number of samples per each frame. Default is1024.taps,tโ set 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. ๐๏ธ
The resulting stream can be used with the afir filter to filter the audio signal.
The filter accepts these options:
preset,pโ set the equalizer preset. Default preset is"flat".
Available presets are:
custom
flat
acoustic
bass
beats
classic
clear
deep bass
dubstep
electronic
hard-style
hip-hop
jazz
metal
movie
pop
r&b
rock
vocal booster
gains,gโ set 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 set the custom bands from where the custom equalizer gains get 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 a frequency in Hz. Default is"25 40 63 100 160 250 400 630 1000 1600 2500 4000 6300 10000 16000 24000".taps,tโ set the number of filter coefficients in the output audio stream. Default value is4096.sample_rate,rโ set the sample rate of the output audio stream, default is44100.nb_samples,nโ set the number of samples per each frame in the output audio stream. Default is1024.interp,iโ set the interpolation method for the FIR equalizer coefficients. Can be"linear"or"cubic".phase,hโ set the phase type of the FIR filter. Can be"linear"or"min"(minimum-phase). Default is a minimum-phase filter.
afirsrc
Generates FIR coefficients using the frequency sampling method. ๐ฆ
The resulting stream can be used with the afir filter to filter the audio signal.
The filter accepts these options:
taps,tโ set the number of filter coefficients in the output audio stream. Default value is1025.frequency,fโ set the frequency points from where magnitude and phase get set. This must be in non-decreasing order, and the first element must be0while the last element must be1. Elements are separated by white spaces.magnitude,mโ set 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 set 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 set the sample rate, default is44100.nb_samples,nโ set the number of samples per each frame. Default is1024.win_func,wโ set the window function. Default isblackman.
๐ anullsrc ๐
The null audio source โ it literally just hands back unprocessed audio frames. Nothing extra, no seasoning. It's mostly useful as a template, and for analysis/debugging tools, or as the source for filters that ignore their input data anyway (like the sox synth filter, iykyk).
This source accepts the following options:
channel_layout,clโ sets the channel layout, and it can be either an integer or a string that represents a channel layout. Default forchannel_layoutis"stereo". The mapping between strings and channel layout values lives in thechannel_layout_mapdefinition inlibavutil/channel_layout.cโ go peek if you're curious ๐sample_rate,rโ sets the sample rate, defaults to44100.nb_samples,nโ sets the number of samples per requested frames.duration,dโ sets the duration of the sourced audio. The accepted syntax is in the Time duration section of theffmpeg-utils(1)manual. If it's not specified, or if the expressed duration is negative, the audio is assumed to be generated forever. infinite vibe fr.
Examples
- Set the sample rate to 48000 Hz and the channel layout to
AV_CH_LAYOUT_MONO.
anullsrc=r=48000:cl=4
- Same operation, but with a more obvious syntax:
anullsrc=r=48000:cl=mono
All the parameters need to be explicitly defined. No vibes-based defaults here, bestie.
๐ฃ๏ธ flite ๐ฃ๏ธ
Synthesizes a voice utterance using the libflite library. She speaks ๐
To enable compilation of this filter you need to configure FFmpeg with --enable-libflite.
Heads up: versions of the flite library prior to 2.0 are not thread-safe.
The filter accepts the following options:
list_voicesโ if set to1, lists the names of the available voices and exits immediately. Default value is0.nb_samples,nโ sets the maximum number of samples per frame. Default value is512.textfileโ sets the filename containing the text to speak.textโ sets the text to speak.voice,vโ sets the voice used for the speech synthesis. Default value is"kal". Also see thelist_voicesoption.
Examples
- Read from the 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 ffplay speak 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/>
๐ anoisesrc ๐
Generates a noise audio signal. Static queen 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. If you don't specify this option, you get noise with an infinite length. endless static arc ๐ญcolor,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 sets the number of samples per each output frame, default is1024.densityโ sets 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
๐ฆ hilbert ๐ฆ
Generates odd-tap Hilbert transform FIR coefficients.
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. math girlie hours โจ
The filter accepts the following options:
sample_rate,sโ sets the sample rate, default is44100.taps,tโ sets the length of the FIR filter, default is22051.nb_samples,nโ sets the number of samples per each frame.win_func,wโ sets the window function to be used when generating FIR coefficients.
๐ sinc ๐
Generates sinc kaiser-windowed low-pass, high-pass, band-pass, or band-reject FIR coefficients.
The resulting stream can be used with the afir filter for filtering the audio signal.
The filter accepts the following options:
sample_rate,rโ sets the sample rate, default is44100.nb_samples,nโ sets the number of samples per each frame. Default is1024.hpโ sets the high-pass frequency. Default is0.lpโ sets the low-pass frequency. Default is0. If the high-pass frequency is lower than the low-pass frequency and the low-pass frequency is higher than0, then the filter creates band-pass filter coefficients โ otherwise it makes band-reject filter coefficients. choose your fighter ๐ซถphaseโ sets the filter phase response. Default is50. Allowed range is from0to100.betaโ sets the Kaiser window beta.attโ sets the stop-band attenuation. Default is120dB, allowed range is from40to180dB.roundโ enables rounding, by default it's disabled.hptapsโ sets the number of taps for the high-pass filter.lptapsโ sets the number of taps for the low-pass filter.
๐ต sine ๐ต
Generates an audio signal made of a sine wave with amplitude 1/8.
The audio signal is bit-exact. no cap, literally bit-exact ๐ฅ
The filter accepts the following options:
frequency,fโ sets the carrier frequency. Default is440Hz.beep_factor,bโ enables 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 sets 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 an 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 the
"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 โจ AUDIO SINKS โจ ๐ธ
Below is a description of the currently available audio sinks.
๐ซถ abuffersink ๐ซถ
Buffers audio frames, and makes them available to the end of the filter chain.
This sink is mainly intended for programmatic use โ 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.
๐ anullsink ๐
Null audio sink; does absolutely nothing with the input audio. genuinely nothing, it's giving "I'm just here" ๐ญ It's mainly useful as a template and for use in analysis / debugging tools.
๐ฆ ๐ VIDEO FILTERS ๐ ๐ฆ
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.
๐ addroi ๐
Marks 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. You can mark multiple regions by applying the filter multiple times. stack 'em ๐ซถ
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-1to+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-1indicates 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-12and51. A typicalqoffsetvalue of-1/10therefore 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 around30, this region would get a QP of around24(an offset of approximately-1/10 * (51 - -12) = -6.3). An extreme value of-1would 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.clearโ if set to true, removes 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
โจ alphaextract โจ
Extracts the alpha component from the input as a grayscale video. This is especially useful with the alphamerge filter. dynamic duo energy ๐
๐
alphamerge ๐
Adds or replaces the alpha component of the primary input with the grayscale value of a second input. This is intended for use with alphaextract, so you can transmit or store frame sequences that have alpha in a format that doesn't support an alpha channel. iconic workaround, honestly ๐
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]
๐ amplify
Amplify the differences between the current pixel and the pixels sitting in the same spot on neighbouring frames. Basically glow-up the delta, bestie โจ
This filter accepts the following options:
radiusโ sets the frame radius. Default is2. Allowed range is from1to63. So like, a radius of3tells the filter to average7frames. Math is math ๐factorโ sets the factor used to amplify the difference. Default is2. Allowed range is from0to65535.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 is from0to65535.toleranceโ sets the tolerance for difference amplification. Any difference lower than this value will not alter the source pixel. Default is0. Allowed range is from0to65535.lowโ sets the lower limit for changing the source pixel. Default is65535. Allowed range is from0to65535. 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 is from0to65535. 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 is from0to15.
๐ฌ Commands
This filter supports the following commands that correspond to the option of the same name:
factorthresholdtolerancelowhighplanes
๐ ass
Same as the subtitles filter, except it doesn't need libavcodec and libavformat to work. On the flip side (๐ญ), it's limited to ASS (Advanced Substation Alpha) subtitle files. Trade-offs, bestie.
This filter accepts the following option in addition to the common options from the subtitles filter:
shapingโ sets the shaping engine.
Available values are:
autoโ the default libass shaping engine, which is the best available. ๐simpleโ fast, font-agnostic shaper that can do only substitutions.complexโ slower shaper using OpenType for substitutions and positioning.
The default is "auto".
๐ฆ atadenoise
Applies an Adaptive Temporal Averaging Denoiser to the video input. Say bye to the grain, not the vibes โจ
The filter accepts the following 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.
So like, 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. Two different personalities, both iconic 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, while the other way around is never true. Parallel will abort early on the first change being greater than the thresholds, while serial will continue processing the other side of the frames if they are equal to or below the thresholds. Fr fr, parallel said "I'm done here" ๐
0s,1s,2sโ set sigma for the 1st plane, 2nd plane or 3rd plane. Default is32767. Valid range is from0to32767. 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. ๐
๐ฌ Commands
This filter supports the same commands as the options, except the option "s". The command accepts the same syntax of the corresponding option.
๐ธ avgblur
Applies an average blur filter. Soft-focus main character energy ๐ซถ
The filter accepts the following 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.
๐ฌ Commands
This filter supports the same commands as the 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.
๐ง backgroundkey
Turns a static background into transparency. Green screen who? Never heard of her โจ
The filter accepts the following option:
thresholdโ threshold for scene change detection.similarityโ similarity percentage with the background.blendโ sets the blend amount for pixels that are not similar.
๐ฌ Commands
This filter supports all of the above options as commands.
โญ bbox
Computes the bounding box for the non-black pixels in the input frame luma plane.
This filter 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. Very "here are the receipts" of it all ๐
The filter accepts the following option:
min_valโ sets the minimal luma value. Default is16.
๐ฌ Commands
This filter supports all of the above options as commands.
๐ bilateral
Applies a bilateral filter โ spatial smoothing while preserving edges. Glow and structure, we love a multitasker ๐
The filter accepts the following options:
sigmaSโ sets the sigma of the gaussian function used to calculate the spatial weight. Allowed range is0to512. Default is0.1.sigmaRโ sets the sigma of the gaussian function used to calculate the range weight. Allowed range is0to1. Default is0.1.planesโ sets the planes to filter. Default is the first only.
๐ฌ Commands
This filter supports all of the above options as commands.
๐ bitplanenoise
Shows and measures bit plane noise.
The filter accepts the following options:
bitplaneโ sets which plane to analyze. Default is1.filterโ filters out noisy pixels from the"bitplane"set above. Default is disabled.
๐ค blackdetect, blackdetect_vulkan
Detects video intervals that are (almost) completely black. Lowkey useful for detecting chapter transitions, commercials, or straight-up invalid recordings ๐
The filter outputs its detection analysis to both the log and 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". In addition, a log line with level "debug" is printed per frame showing the black amount detected for that frame.
The filter also attaches metadata to the first frame of a black segment with the key "lavfi.black_start", and to the first frame after the black segment ends with the key "lavfi.black_end". The value is the frame's timestamp. This metadata is added regardless of the minimum duration specified. No cap.
The filter accepts the following 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. Detects frames which are (almost) transparent, instead of frames which are almost black.
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
๐ blackframe
Detects frames that are (almost) completely black. Can be useful to detect chapter transitions or commercials. 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.
In order to display the output lines, you need to set the loglevel at least to the AV_LOG_INFO value. Don't skip this step or you'll be staring at nothing, bestie 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.
๐ blend
Blends two video frames into each other. Collab era โจ
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 one 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:
okay so like, the blend modes?? there are SO many and they're all iconic in their own way ๐ here's the full roster, no crumbs left behind:
additionandaveragebleachburndarkendifferencedividedodgeexclusionextremityfreezegeometricglowgrainextractgrainmergehardlighthardmixhardoverlayharmonicheatinterpolatelightenlinearlightmultiplymultiply128negationnormaloroverlayphoenixpinlightreflectscreensoftdifferencesoftlightstainsubtractvividlightxor
๐ธ the opacity girlies
c0_opacity,c1_opacity,c2_opacity,c3_opacity,all_opacityโ sets the blend opacity for one specific pixel component, or for all of them when you useall_opacity. heads up bestie: this only does anything when you're using pixel-component blend modes. iykyk
โจ the expression girlies (yes there are two flavors)
c0_expr,c1_expr,c2_expr,c3_expr,all_exprโ sets the blend expression for a specific pixel component, or for all of them withall_expr. important: if you set these, the related mode options get ignored. like, completely. ๐
So what can you actually put in these expressions? These variables, bestie:
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 currently filtered plane.SW,SHโ the 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 for ayuv420pframe the values are1,1for the luma plane and0.5,0.5for the chroma planes ๐ฆTโ time of the current frame, expressed in seconds.TOP,Aโ value of the pixel component at the current location for the first video frame (the top layer).BOTTOM,Bโ value of the pixel component at the current location for the second video frame (the bottom layer).
also the blend filter supports the framesync options, obviously ๐โโ๏ธ
๐ Examples (eat these up)
- apply a transition from the bottom layer to the top layer over the first 10 seconds:
blend=all_expr='A*(if(gte(T,10),1,T/10))+B*(1-(if(gte(T,10),1,T/10)))'
- apply a linear horizontal transition from the top layer to the bottom layer:
blend=all_expr='A*(X/W)+B*(1-X/W)'
- apply a
1x1checkerboard effect:
blend=all_expr='if(eq(mod(X,2),mod(Y,2)),A,B)'
- apply the uncover-left effect:
blend=all_expr='if(gte(N*SW+X,W),A,B)'
- apply the uncover-down effect:
blend=all_expr='if(gte(Y-N*SH,0),A,B)'
- apply the 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 the video diagonally and show the top layer on one side and the bottom layer on the other:
blend=all_expr='if(gt(X,Y*(W/H)),A,B)'
- display the differences between the current frame and the previous one:
tblend=all_mode=grainextract
Commands
this filter supports the same commands as options ๐ซถ
๐ blockdetect
figures out how blocky your frames are โ and like, without touching them at all. the input frames come out exactly as they went in, it's just reporting ๐
based on Remco Muijs and Ihor Kirenko: "A no-reference blocking artifact measure for adaptive video processing." 2005 13th European signal processing conference.
options, let's go:
period_min,period_maxโ set the minimum and maximum values for determining pixel grids (periods). the default values are[3,24].planesโ set which 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
๐ฆ blurdetect
same vibe, different metric: it determines how blurry your frames are without altering them. based on Marziliano, Pina, et al. "A no-reference perceptual blur metric." it also allows for a block-based abbreviation.
options time:
low,highโ set the low and high threshold values used by the Canny thresholding algorithm.
the high threshold picks out the "strong" edge pixels, which then get connected through 8-connectivity with the "weak" edge pixels that the low threshold selected.
low and high have to be in the range [0,1], and low should be lesser or equal to high (don't be chaotic about it ๐).
the default value for low is 20/255, and the default value for high is 50/255.
radiusโ defines 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 than1, 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 than1, 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 the most significant
32x32blocks:
blurdetect=block_width=32:block_height=32:block_pct=80
๐ bm3d
denoises frames using the Block-Matching 3D algorithm. yes it's as fancy as it sounds โจ
the options:
sigmaโ set the denoising strength. default value is1. allowed range is from0to999.9. ngl the denoising algorithm is very sensitive tosigma, so adjust it according to the source. fr fr, tune itblockโ set the local patch size. this sets dimensions in 2D.bstepโ set the sliding step for processing blocks. default value is4. allowed range is from1to64. smaller values allow processing more reference blocks and is slower (tragic but real ๐ญ).groupโ set the maximal number of similar blocks for the 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 the radius for search block matching. default is9. allowed range is from1toINT32_MAX.mstepโ set the step between two search locations for block matching. default is1. allowed range is from1to64. smaller is slower.thmseโ set the threshold of mean square error for block matching. valid range is0toINT32_MAX.hdthrโ set the thresholding parameter for hard thresholding in the 3D transformed domain. larger values result in stronger hard-thresholding filtering in the frequency domain.estimโ set the filtering estimation mode. can bebasicorfinal. default isbasic.refโ if enabled, the filter will use the 2nd stream for block matching. default is disabled for thebasicvalue 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 the
nlmeansfilter 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
๐ boxblur
applies a boxblur algorithm to the input video. soft focus moment ๐
it accepts these parameters:
luma_radius,lrluma_power,lpchroma_radius,crchroma_power,cpalpha_radius,aralpha_power,ap
and here's the full description of the accepted options:
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 limit bestie
the 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 these 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,hsubis2andvsubis1.
luma_power,lp,chroma_power,cp,alpha_power,apโ specify how many times the boxblur filter is applied to the corresponding plane.
the 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. (zero effort, zero blur, we love a lazy queen ๐)
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 the alpha and chroma radius to0:
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
โญ bwdif
deinterlaces the input video. also, bwdif stands for "Bob Weaver Deinterlacing Filter" โ yes, a whole acronym for a name, main character energy honestly.
it's motion adaptive deinterlacing based on yadif with the use of w3fdif and cubic interpolation algorithms. it accepts these 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. accepts one of these: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
Okay so this one repacks CEA-708 closed captioning side data โ it's basically the glow-up artist for your captions. โจ
It fixes a whole bunch of issues that people see with commercial encoders related to upstream malformed CEA-708 payloads, specifically:
- incorrect number of tuples (wrong
cc_countfor the target FPS), and - incorrect ordering of tuples (i.e. the CEA-608 tuples are not at the first entries in the payload).
No cap, that's it, that's the whole filter. ๐ซถ
๐ cas
Apply the Contrast Adaptive Sharpen filter to your video stream. Crispy edges, bestie. ๐ฅ
The filter accepts the following options:
strengthโ set the sharpening strength. Default value is0. (Yeah, zero means no sharpening, so likeโฆ turn it up, babe ๐ )planesโ set which planes to filter. Default is to filter all planes except the alpha plane.
Commands
This filter supports the same commands as options. ๐ฎ
๐ chromahold
Removes all color information for all colors except for one certain one. It's giving "keep only the main character, everyone else go gray." ๐
The filter accepts the following options:
colorโ the color which will not be replaced with neutral chroma. The chosen one. โจsimilarityโ similarity percentage with the above color.0.01matches only the exact key color, while1.0matches everything. Wild range, honestly.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 withyuvenabled anymore. This can be used to pass exact YUV values as hexadecimal numbers. ๐ง
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 chromakey
YUV colorspace color/chroma keying. This is THE greenscreen filter, iykyk. ๐
The filter accepts the following options:
colorโ the color which will be replaced with transparency. Bye bye ๐similarityโ 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 pixel's color is to the key color. Soft edges, slay. ๐ฆyuvโ signals that the color passed is already in YUV instead of RGB.
Literal colors like"green"or"red"don't make sense withyuvenabled anymore. This can be used to pass exact YUV values as hexadecimal numbers. ๐ธ
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.
Examples ๐
- 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. Like a little skincare routine but for your video's color channels. ๐งโโ๏ธ
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. โกstephโ 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 is manhattan.
Commands
This filter supports the same commands as options. The command accepts the same syntax of the corresponding option.
๐ chromashift
Shift chroma pixels horizontally and/or vertically. Little scoot for the color channels. 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.
Commands
This filter supports the all above options as commands. ๐ฎ
๐ ciescope
Display a CIE color diagram with pixels overlaid onto it. Science girlie aesthetic, honestly iconic. ๐ฌ๐
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. See the"system"option for available values. ๐size,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. ๐จ
๐ codecview
Visualize information exported by some codecs. It's the "show me what the codec is actually thinking" filter. ๐ง โจ
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 by theframe_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)
Examples ๐
- 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
๐ colorbalance
Modify intensity of primary colors (red, green and blue) of input frames. Color grading era, we love to see it. ๐จ๐
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. Positive = this way, negative = the opposite way, got it? ๐ซถ
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 are 0.
plโ preserve lightness when changing color balance. Default is disabled.
Examples ๐ธ
- Add red color cast to shadows:
colorbalance=rs=.3
Commands
This filter supports the all above options as commands. ๐ฎ
๐ colorcontrast
Adjust color contrast between RGB components. Fancy. โจ
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. โ ๏ธ (so like, weights are literally the on switch, don't forget them)plโ set the amount of preserving lightness. Default value is0.0. Allowed range is from0.0to1.0.
Commands
This filter supports the all above options as commands. ๐
๐ colorcorrect
Adjust color white balance selectively for blacks and whites. This filter operates in YUV colorspace. Selective queen. ๐
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:manualaverageminmaxmedian
Default value is "manual".
Commands
This filter supports the all above options as commands. ๐
๐จ colorchannelmixer
Bestie, this one remixes your color channels like it's making a playlist ๐ฟ โ it adjusts video input frames by re-mixing the color channels.
Here's the vibe: it modifies one color channel by adding up the values of the other channels of the same pixels. So if the value you're tweaking is red, your output value comes out as:
<red>=<red>*<rr> + <blue>*<rb> + <green>*<rg> + <alpha>*<ra>
The filter accepts these options:
rr,rg,rb,raโ adjust how much the input red, green, blue and alpha channels contribute to the output red channel. Default is1forrr, and0forrg,rbandra.gr,gg,gb,gaโ adjust how much the input red, green, blue and alpha channels contribute to the output green channel. Default is1forgg, and0forgr,gbandga.br,bg,bb,baโ adjust how much the input red, green, blue and alpha channels contribute to the output blue channel. Default is1forbb, and0forbr,bgandba.ar,ag,ab,aaโ adjust how much the input red, green, blue and alpha channels contribute to the output alpha channel. Default is1foraa, and0forar,agandab.
Allowed ranges for all of these options are [-2.0, 2.0] ๐ซถ
pcโ set the preserve color mode. Accepted values:noneโ disable color preserving, this is the default ๐คlumโ preserve luminancemaxโ preserve max value of RGB tripletavgโ preserve average value of RGB tripletsumโ preserve sum value of RGB tripletnrmโ preserve normalized value of RGB tripletpwrโ preserve power value of RGB triplet
paโ set the preserve color amount when changing colors. Allowed range is[0.0, 1.0]. Default is0.0, so like, disabled by default, no cap.
โจ Examples
- Convert source to grayscale:
colorchannelmixer=.3:.4:.3:0:.3:.4:.3:0:.3:.4:.3
- Simulate sepia tones (so aesthetic ๐๏ธ):
colorchannelmixer=.393:.769:.189:0:.349:.686:.168:0:.272:.534:.131
๐น๏ธ Commands
This filter supports the all above options as commands.
๐ colordetect
Okay so this one literally analyzes the video frames to figure out the effective value range and alpha mode. It's giving detective energy ๐ต๏ธโโ๏ธ
The filter accepts the following options:
modeโ the set of properties to detect. Unavailable properties (like alpha mode for an input image with no alpha channel) get ignored automatically, no drama.
Accepts a combination of these 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 ๐
๐ colorize
Overlay a solid color on the video stream. It's like putting a gel over the lens, lowkey iconic.
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.
๐น๏ธ Commands
This filter supports the all above options as commands.
๐ฉ colorkey
RGB colorspace color keying, aka the greenscreen filter of your dreams 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 the"Color"section in theffmpeg-utilsmanual. 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.
โจ 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:
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
๐น๏ธ 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.
๐ฏ colorhold
Remove all color information for all RGB colors except for a certain one. It's the "everyone wears gray except the main character" filter, fr fr ๐
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.
๐น๏ธ 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 colorlevels
Adjust video input frames using levels. Think of it as the sliders panel in your editing app ๐๏ธ
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), and 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 allow manual selection of a constrained output level range.
preserveโ set preserve color mode. Accepted values:noneโ disable color preserving, this is the default ๐คlumโ preserve luminancemaxโ preserve max value of RGB tripletavgโ preserve average value of RGB tripletsumโ preserve sum value of RGB tripletnrmโ preserve normalized value of RGB tripletpwrโ preserve power value of RGB triplet
โจ 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
๐น๏ธ Commands
This filter supports the all above options as commands.
๐บ๏ธ colormap
Apply custom color maps to video stream. This one's a whole group project โ it needs three input video streams, okay?
First stream is the video stream that is going to be filtered out. Second and third video stream specify color patches for source color to target color mapping.
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 the 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".
๐ colormatrix
Convert color matrix. Simple as that, bestie.
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
๐จ colorspace
Convert colorspace, transfer characteristics or color primaries. Heads up though โ input video needs to have an even size or this whole thing falls apart ๐ญ
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
โฆand here's the rest of the trc squad, because she has range ๐
:
iec61966-2-1โ iec61966-2-1iec61966-2-4โ iec61966-2-4xvyccโ xvyccbt2020-10โ BT.2020 for 10-bits contentbt2020-12โ BT.2020 for 12-bits content
primaries โ okay so this one sets your output color primaries, bestie. Accepted values, no cap:
bt709โ BT.709bt470mโ BT.470Mbt470bgโ BT.470BG or BT.601-6 625smpte170mโ SMPTE-170M or BT.601-6 525smpte240mโ SMPTE-240Mfilmโ filmsmpte431โ SMPTE-431smpte432โ SMPTE-432bt2020โ BT.2020jedec-p22โ JEDEC P22 phosphors
range โ sets your output color range โจ accepted values:
tvโ TV (restricted) rangempegโ MPEG (restricted) rangepcโ PC (full) rangejpegโ JPEG (full) range
format โ sets your output color format ๐ accepted values:
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 โ does a fast conversion that justโฆ skips gamma/primary correction entirely ๐ it uses significantly less CPU, but it's mathematically incorrect, so like, know what you're signing up for. If you want output that matches what the colormatrix filter produces, go fast=1.
dither โ picks your dithering mode:
noneโ no dithering at allfsbโ Floyd-Steinberg dithering
wpadapt โ whitepoint adaptation mode:
bradfordโ Bradford whitepoint adaptationvonkriesโ von Kries whitepoint adaptationidentityโ identity whitepoint adaptation (i.e. no whitepoint adaptation)
clipgamut โ controls how out-of-gamut colors get clipped when they 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 โ overrides all the input properties at once ๐ซถ same accepted values as all.
ispace โ overrides input colorspace. Same accepted values as space.
iprimaries โ overrides input color primaries. Same accepted values as primaries.
itrc โ overrides input transfer characteristics. Same accepted values as trc.
irange โ overrides input color range. Same accepted values as range.
So the way this filter works, bestie: it converts the transfer characteristics, color space and color primaries over to whatever values you specified. The output value โ if you didn't specify it โ gets set to a default based on the all property. And if that property isn't specified either? The filter logs an error, periodt. The output color range and format default to the same value as the input's color range and format. Your input transfer characteristics, color space, color primaries and color range should be set on the input data โ if any of those are missing, the filter logs an error and no conversion takes place. Like, none. Zero. ๐
So for example, to convert the input to SMPTE-240M, you'd run:
colorspace=smpte240m
๐ก๏ธ colortemperature
Adjusts the color temperature in video, so you can simulate variations in ambient color temperature. Iconic little mood-lighting filter honestly.
Accepts these options:
temperatureโ sets the temperature in Kelvin. Allowed range is from1000to40000. Default value is6500K.mixโ sets mixing with filtered output. Allowed range is from0to1. Default value is1.plโ sets the amount of preserving lightness. Allowed range is from0to1. Default value is0.
Commands
This filter supports same commands as options. Slay.
๐ convolution
Applies a convolution of 3x3, 5x5, 7x7, or horizontal/vertical up to 49 elements. It's givingโฆ math but make it fashion.
Accepts these options:
0m,1m,2m,3mโ set 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.0rdiv,1rdiv,2rdiv,3rdivโ set multiplier for calculated value for each plane. If unset or0, it will be1/sumof all matrix elements.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. Default is0.0.0mode,1mode,2mode,3modeโ set matrix mode for each plane. Can besquare,roworcolumn. Default issquare.
Commands
This filter supports the all above options as commands ๐ฅ
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"
๐ฆ convolve
Applies a 2D convolution of the video stream in the frequency domain, using a second stream as the impulse. Fancy. Academic. Obsessed.
Accepts these options:
planesโ set which planes to process.impulseโ set which impulse video frames will be processed; can befirstorall. Default isall.
Heads up bestie: the convolve filter also supports the framesync options.
๐ copy
Copies the input video source unchanged to the output. It's mainly useful for testing purposes โ like a little "are you even running" vibe check โจ
๐ coreimage
Video filtering on GPU using Apple's CoreImage API on OSX. Very main character energy.
Hardware acceleration is based on an OpenGL context. Usually, this means it's processed by video hardware. However โ software-based OpenGL implementations exist, which means there's genuinely no guarantee of hardware processing. It depends on the respective OSX, ngl.
Apple provides many filters and image generators 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 and the default values. Like this:
list_filters=true
filterโ specify all filters by their respective name and options. Uselist_filtersto figure out all valid filter names and options. Numerical options are given as a float value and get 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. And there's a special option namedefaultavailable to use default options for a filter.
It's required to specify either default or at least one of the filter options. All omitted options get 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 gets copied into the input image. It's given by a list of space separated float values:
output_rect=x\ y\ width\ height
If you don't give it, 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, iykyk.
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 โ like they exist but they're not serving the fantasy yet ๐
Some filters generate output images with additional padding, depending on the respective filter kernel. The padding gets automatically removed so the filter output has the same size as the input image.
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 don't use the pixel information of this image to generate their output. However, the generated output is blended onto this image, which results in partial or complete coverage of the output image. Blend, slay, repeat ๐
You can use the coreimagesrc video source to generate input images that get fed directly into the filter chain. By using it, providing input images by another video source or an input video isn't required at all.
Examples
- List all filters available:
coreimage=list_filters=true
- Use the
CIBoxBlurfilter with default options to blur an image:
coreimage=filter=CIBoxBlur@default
- Use a filter chain with
CISepiaToneat default values andCIVignetteEffectwith its center at 100x100 and a radius of 50 pixels:
coreimage=filter=CIBoxBlur@default#CIVignetteEffect@inputCenter=100\ 100@inputRadius=50
- Use
nullsrcandCIQRCodeGeneratorto 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
๐ corr
Obtains the correlation between two input videos. This filter takes two input videos โ yes, two, it's a whole duet situation ๐ซถ
Both input videos must have the same resolution and pixel format for this filter to work correctly โ no cap, it just won't vibe otherwise ๐. It also assumes both inputs have the same number of frames, which get compared one by one.
The obtained per component, average, min and max correlation is printed through the logging system (so keep an eye on your logs, bestie ๐).
The filter stores the calculated correlation of each frame in frame metadata โจ.
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 ๐:
ffmpeg -i main.mpg -i ref.mpg -lavfi corr -f null -
๐ซถ cover_rect
Cover a rectangular object. Iconic behaviour, honestly ๐ .
It accepts the following options:
coverโ Filepath of the optional cover image, needs to be inyuv420. Yes,yuv420, it's picky like that.modeโ Set covering mode. It accepts the following values:coverโ cover it by the supplied image ๐ผ๏ธblurโ cover it by interpolating the surrounding pixels ๐ซ๏ธ
Default value is blur.
๐ธ 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
โ๏ธ crop
Crop the input video to given dimensions. Literally the makeover filter ๐.
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. This expression is evaluated only once during the 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 expression is evaluated per-frame.keep_aspectโ If set to1will force the output display aspect ratio to be the same of the input, by changing the output sample aspect ratio. It defaults to0.exactโ Enable exact cropping. If enabled, subsampled videos will be cropped at exact width/height/x/y as specified and will not be rounded to 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 forxandy. They are 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 is the same as(iw / ih) * sarhsub,vsubโ horizontal and vertical chroma subsample values. For example for the pixel formatyuv422phsubis2andvsubis1.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 โ ๏ธtโ The timestamp expressed in seconds. It'sNANif the input timestamp is unknown.
The expression for out_w may depend on the value of out_h, and the expression for out_h may depend on out_w, but they cannot depend on x and y, as x and y are evaluated after out_w and out_h. Order matters, bestie ๐ซ .
The x and y parameters specify the expressions for the position of the top-left corner of the output (non-cropped) area. They are evaluated for each frame. If the evaluated value is not valid, it is approximated to the nearest valid value.
The expression for x may depend on y, and the expression for y may depend on x. Mutual dependency, we love to see it ๐.
๐ 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)
๐ Commands
This filter supports the following commands:
w,out_w,h,out_h,x,yโ Set width/height of the output video and the horizontal/vertical position in 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.
๐ cropdetect
Auto-detect the crop size. It literally does your homework for you ๐ญโจ.
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 according to mode.
It accepts the following parameters:
modeโ Depending onmodecrop 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 higher black value threshold, which can be optionally specified from nothing (0) to everything (255for 8-bit based formats). An intensity value greater to the set value is considered non-black. It defaults to24. You can also specify a value between0.0and1.0which 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 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.
Default value for low is 5/255, and default value for high is 15/255.
๐ฆ 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 -
๐ Commands
This filter supports the following commands:
limitโ The command accepts the same syntax of the corresponding option. If the specified expression is not valid, it is kept at its current value.
โฐ cue
Delay video filtering until a given wallclock timestamp โณ. 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 its input.
The filter can be used 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. Lowkey honest of it ๐ซถ.
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.
๐จ curves
Apply color adjustments using curves. It's giving Adobe Photoshop meets GIMP, and honestly? Ate 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. Iconic minimalism, honestly โจ.
So like, this filter lets you redefine those two points and add even more โ a brand new curve gets drawn so it passes smoothly through all your new coordinates. The new points have to be strictly increasing along the x-axis, and both their x and y values gotta live in the [0;1] interval. The curve itself is made with either a natural or monotonic cubic spline interpolation, depending on the interp option (default: "natural"). The "natural" spline gives you a smoother curve overall, while the monotonic ("pchip") spline guarantees the transitions between your points stay monotonic. And if the computed curves wander outside the vector spaces? Values get clipped accordingly. ๐
The filter accepts the following options:
presetโ pick one of the available color presets. You can totally use this in addition to ther,g,bparameters โ and in that case, the later options win over the preset values. The presets are:nonecolor_negativecross_processdarkerincrease_contrastlighterlinear_contrastmedium_contrastnegativestrong_contrastvintage
Default is "none".
master,mโ set the master key points. These define a second pass mapping, sometimes called a "luminance" or "value" mapping. Works 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 includingmaster). Can be used alongside the other per-component key point options โ and in that case, any component you didn't set falls back on thisallsetting.psfileโ specify a Photoshop curves file (".acv") to import the settings from.plotโ save a Gnuplot script of the curves into the file you specify.interpโ specify the kind of interpolation. The available algorithms are:naturalโ natural cubic spline using a piece-wise cubic polynomial that's twice continuously differentiable.pchipโ monotonic cubic spline using a piecewise cubic Hermite interpolating polynomial (PCHIP).
To dodge some filtergraph syntax conflicts, each key points list has to be defined using this syntax: "x0/y0 x1/y1 x2/y2 ...".
Commands
This filter supports the same commands as options. โจ
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 components:
red "(0;0.11) (0.42;0.51) (1;0.95)"
green โ "(0;0) (0.50;0.48) (1;1)"
blue โ "(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. ๐ต๏ธโโ๏ธ
This filter shows hexadecimal pixel values of part of video โ literally the pixels but in numbers, iykyk.
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 a color background picked from the input video, and the text color is picked in such a way so it's always visible.
axisโ draw rows and columns numbers on the left and top of the 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 the same commands as options, excluding the "size" option. ๐
dblur
Apply Directional blur filter.
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 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. ๐
dctdnoiz
Denoise frames using 2D DCT (frequency domain filtering).
Heads up bestie โ this filter is not designed for real time. ๐ซ
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 the 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<<ndefines 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 processing speed. Also, a larger block size doesn't necessarily mean better de-noising. ๐
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. โจ
The filter accepts the following options:
1thr2thr3thr4thr
Set banding detection threshold for each plane. Default is 0.02. Valid range is 0.00003 to 0.5. If the difference between the current pixel and the reference pixel is less than the threshold, it'll be considered as banded.
range,rโ banding detection range in pixels. Default is16. If positive, a random number in range0to the set value will be used. If negative, the exact absolute value will be used. The range defines a square of four pixels around the current pixel.direction,dโ set direction in radians from which four pixels will be compared. If positive, a random direction from0to the set direction will be picked. If negative, the exact absolute value will be picked. For example, direction0,-PIor-2*PIradians will pick only pixels on the same row, and-PI/2will pick only pixels on the same column.blur,bโ if enabled, the current pixel is compared with the average value of all four surrounding pixels. The default is enabled. If disabled, the current pixel is compared with all four surrounding pixels. The pixel is considered banded if only all four differences with surrounding pixels are less than threshold.coupling,cโ if enabled, the current pixel is changed if and only if all pixel components are banded โ e.g. the banding detection threshold is triggered for all color components. The default is disabled.
Commands
This filter supports the all above options as commands. ๐
deblock
Remove blocking artifacts from input video.
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.alphabetagammadelta
Set blocking detection thresholds. Allowed range is 0 to 1. Defaults are: 0.098 for alpha and 0.05 for the rest. Using a higher threshold gives more deblocking strength. Setting alpha controls 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 to 0 disables 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. ๐
decimate
Drop duplicated frames at regular intervals.
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 sets the threshold for duplicate detection. If a frame's difference metric is less than or equal to this value, it gets declared a duplicate. Default is1.1. So basically the "are these two frames the same pic, bestie?" line โจscthreshโ sets the scene change threshold. Default is15. Lowkey the "is this a new scene or nah" detector ๐ฌblockx,blockyโ set the size of the x and y-axis blocks used during metric calculations. Bigger blocks = better noise suppression, but also = worse detection of small movements. Must be a power of two. Default is32. Not optional, she's doing math ๐ppsrcโ marks the main input as a pre-processed input and activates the clean source input stream. This lets the input be pre-processed 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 is0. Two streams, one glow-up, zero quality loss ๐ซถchromaโ sets whether or not chroma is considered in the metric calculations. Default is1. Color girlies stay winning ๐mixedโ sets whether or not the input only partially contains content to be decimated. Default is"false". If enabled, the video output stream will be in variable frame rate. Heads up, that VFR is real ๐
โจ deconvolve โจ
Applies 2D deconvolution of the video stream in the frequency domain using the second stream as impulse. It's giving "un-blur me with science" ๐ฌ๐
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 noise when doing divisions. Default is0.0000001. Super useful when width and height are not the same and not a power of 2, or if the stream prior to convolving had noise. Tiny number, huge job ๐
The deconvolve filter also supports the framesync options.
โจ dedot โจ
Reduces cross-luminance (aka dot-crawl) and cross-color (aka rainbows) from video. The most cursed little visual artifacts, gone โจ๐
It accepts the following options:
mโ set mode of operation. Can be a combination ofdotcrawlfor cross-luminance reduction and/orrainbowsfor cross-color reduction.ltโ set spatial luma threshold. Lower values increase reduction of cross-luminance.tlโ set tolerance for temporal luma. Higher values increase reduction of cross-luminance.tcโ set tolerance for chroma temporal variation. Higher values increase reduction of cross-color.ctโ set temporal chroma threshold. Lower values increase reduction of cross-color.
โจ deflate โจ
Applies a deflate effect to the video. This filter replaces the pixel by the local (3x3) average, but only takes into account values lower than the pixel. Squish, but make it respectful ๐
It accepts the following options:
threshold0,threshold1,threshold2,threshold3โ limit the maximum change for each plane. Default is65535. If0, that plane will remain unchanged. Like a "do not touch" sign for that channel ๐ซ
Commands โ this filter supports all the above options as commands. Yes bestie, you can change them at runtime ๐
โจ deflicker โจ
Removes temporal frame luminance variations. The flickering was giving migraine energy, so bye ๐
It accepts the following options:
size,sโ set moving-average filter size in frames. Default is5. Allowed range is2-129.mode,mโ set averaging mode to smooth temporal luminance variations.
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 one only wants metadata. All vibes, no pixels ๐
โจ deinterlace_d3d12 โจ
Deinterlaces the input video using D3D12 hardware-accelerated video processing. GPU said "I got this" ๐๐ฅ
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. No format, no party โ that's a whole requirement, not a suggestion.
The filter automatically queries the hardware for the required number of temporal reference frames (if needed) and manages a frame queue to supply them. Self-sufficient icon ๐
It accepts the following options:
methodโ the deinterlacing method. It 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 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.customโ 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. It 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. Double the frames, double the drama ๐ฅ
The default value is "frame".
deintโ specify which frames to deinterlace. It 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".
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 d3d12 pipeline):
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
โจ dejudder โจ
Removes judder produced by partially interlaced telecined content. The stutter was NOT it ๐ญ
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. So yeah โ VFR warning, bestie, keep that in mind ๐ซถ
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 delogo โจ
Suppresses a TV station logo by a simple interpolation of the surrounding pixels. Just set a rectangle covering the logo and watch it disappear (and sometimes something even uglier appear โ your mileage may vary). Ngl this filter is a little chaotic, but iconic ๐๐
It accepts the following parameters:
x,yโ specify the top left corner coordinates of the logo. They must be specified. Non-negotiable, she needs the corner ๐w,hโ specify the width and height of the logo to clear. They must be specified. Also non-negotiable.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. So the green box is basically a little aura showing you where the magic happens 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
โจ derain โจ
Removes the rain in the input image/video by applying the derain methods based on convolutional neural networks. Yes, she's an AI filter, and yes, she ate ๐ง๏ธ๐ฅ
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>. Go be a scientist, bestie ๐ง
The filter accepts the following options:
filter_typeโ specify which filter to use. This option accepts the following values:derainโ Derain filter. To conduct derain filter, you need to use a derain model.dehazeโ Dehaze filter. To conduct 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. This option accepts the following values:tensorflowโ TensorFlow backend. To enable this backend you need to install the TensorFlow for C library (see <https://www.tensorflow.org/install/lang_c>) and configure FFmpeg with"--enable-libtensorflow".
modelโ set path to the model file specifying network architecture and its parameters. Note that different backends use different file formats. TensorFlow can load files for only its format. Kind of a "read the room" situation for file formats ๐
To get full functionality (such as async execution), please use the dnn_processing filter.
โจ deshake โจ
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. Your shaky walking-vlog era is over, we're stabilizing her ๐ฆ
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. Fr, if your bestie is dancing in frame, she's not camera shake โ don't let the vectors get confused ๐
If any or all of x, y, w and h are set to -1, then the full frame is used. This lets later options be set without specifying the bounding box for the motion vector search.
Default: search the whole frame.
rx,ryโ Specify the maximum extent of movement in x and y directions in the range0-64pixels. Default16.edgeโ Specify how to generate pixels to fill blanks at the edge of the frame. Available values are:blank,0โ Fill zeroes at blank locations.original,1โ Original image at blank locations.clamp,2โ Extruded edge value at blank locations.mirror,3โ Mirrored edge at blank locations. Default value ismirror.
blocksizeโ Specify the blocksize to use for motion search. Range4-128pixels, default8.contrastโ Specify the contrast threshold for blocks. Only blocks with more than the specified contrast (difference between darkest and lightest pixels) will be considered. Range1-255, default125.searchโ Specify the search strategy. Available values are:exhaustive,0โ Set exhaustive search.less,1โ Set less exhaustive search. Default value isexhaustive.
filenameโ If set, a detailed log of the motion search is written to the specified file.
๐ despill ๐
Remove unwanted contamination of foreground colors, caused by reflected color of greenscreen or bluescreen.
This filter accepts the following options, bestie:
typeโ Set what type of despill to use.mixโ Set how spillmap will be generated.expandโ Set how much to get rid of still remaining spill.redโ Controls amount of red in spill area.greenโ Controls amount of green in spill area. Should be-1for greenscreen.blueโ Controls amount of blue in spill area. Should be-1for bluescreen.brightnessโ Controls brightness of spill area, preserving colors.alphaโ Modify alpha from generated spillmap.
๐ฎ Commands ๐ฎ
This filter supports all the above options as commands.
๐ detelecine ๐
Apply an exact inverse of the telecine operation. It requires a predefined pattern specified using the pattern option, which must be the same as that passed to the telecine filter.
This filter accepts the following options:
first_fieldโ Available values are:top,tโ top field firstbottom,bโ bottom field first The default value is"top".
patternโ A string of numbers representing the pulldown pattern you wish to apply. The default value is23.start_frameโ A number representing position of the first frame with respect to the telecine pattern. This is to be used if the stream is cut. The default value is0.
๐ธ dilation ๐ธ
Apply dilation effect to the video.
This filter replaces the pixel by the local(3x3) maximum.
It accepts the following options:
threshold0,threshold1,threshold2,threshold3โ Limit the maximum change for each plane, default is65535. If0, plane will remain unchanged.coordinatesโ Flag which specifies the pixel to refer to. Default is255, i.e. all eight pixels are used.
Flags to local 3x3 coordinates maps like this:
1 2 3
4 5
6 7 8
๐ฎ Commands ๐ฎ
This filter supports all the above options as commands.
๐ฆ displace ๐ฆ
Displace pixels as indicated by second and third input stream.
It takes three input streams and outputs one stream, the first input is the source, and second and third input 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 displacement map streams terminates, last frame from that displacement map will be used.
Note that once generated, displacements maps can be reused over and over again.
A description of the accepted options follows.
edgeโ Set displace behavior for pixels that are out of range. Available values are: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 other side.mirrorโ Out of range pixels will be replaced with mirrored pixels. Default issmear.
โจ Examples โจ
- Add ripple effect to 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 wave effect to 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
๐ง dnn_classify ๐ง
Do classification with deep neural networks based on bounding boxes.
The filter accepts the following options:
dnn_backendโ Specify which DNN backend to use for model loading and execution. This option accepts onlyopenvinonow, tensorflow backends will be added.modelโ Set path to 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 path to label file specifying the mapping between label id and name. Each label name is written in one line, trailing spaces and empty lines are skipped. The first line is the name of label id0, and the second line is the name of label id1, etc. The label id is considered as name if the label file is not provided.backend_configsโ Set the configs to be passed into backend. For tensorflow backend, you can set its configs withsess_configoptions, please usetools/python/tf_sess_config.pyto get the configs for your system.
๐ dnn_detect ๐
Do object detection with deep neural networks.
The filter accepts the following options:
dnn_backendโ Specify which DNN backend to use for model loading and execution. This option accepts onlyopenvinonow, tensorflow backends will be added.modelโ Set path to 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 path to label file specifying the mapping between label id and name. Each label name is written in one line, trailing spaces and empty lines are skipped. The first line is the name of label id0(usually it is 'background'), and the second line is the name of label id1, etc. The label id is considered as name if the label file is not provided.backend_configsโ Set the configs to be passed into backend. To use async execution, setasync(default:set). Roll back to sync execution if the backend does not support async.
๐ dnn_processing ๐
Do image processing with deep neural networks. It works together with another filter which converts the pixel format of the Frame to what 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 (see<https://www.tensorflow.org/install/lang_c>) and configure FFmpeg with--enable-libtensorflow.openvinoโ OpenVINO backend. To enable this backend you need to build and install the OpenVINO for C library (see<https://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 are not installed into system path).torchโ Libtorch backend. To enable this backend you need to build and install Libtroch for C++ library. Please download cxx11 ABI version (see<https://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/.
modelโ Set path to model file specifying network architecture and its parameters. Note that different backends use different file formats. TensorFlow, OpenVINO and Libtorch backend can load files for only its 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 backend. To use async execution, setasync(default:set). Roll back to sync execution if the backend does not support async. For tensorflow backend, you can set its configs withsess_configoptions, please usetools/python/tf_sess_config.pyto get the configs of TensorFlow backend for your system.
โจ Examples โจ
- Remove rain in rgb24 frame with
can.pb(see derain filter):
./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 sr filter) for frame withyuv420p(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 sr filter), which changes frame size, for formatyuv420p(planar YUV formats supported), please usetools/python/tf_sess_config.pyto get the configs of 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
Okay bestie, this one draws a colored box right on top of the input image. It's giving literal highlighter energy. โจ
It accepts the following parameters:
x,yโ the expressions that specify the top left corner coordinates of the box. Defaults to0.width,wandheight,hโ the expressions specifying the width and height of the box; if they're0they get interpreted as the input width and height. Defaults to0.color,cโ specify the color of the box to write. For the general syntax of this option, check the "Color" section in theffmpeg-utilsmanual. If the special valueinvertis used, the box edge color is the same as the video with inverted luma. ๐thickness,tโ the expression that sets the thickness of the box edge. A value offillwill create a filled box (obsessed actually). Default value is3.
See below for the list of accepted constants.
replaceโ applicable if the input has alpha. 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, 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,ihandin_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. Mutual reference slay ๐
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
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. No crash, no drama, it just stays exactly where it is. ๐ซถ
๐ drawgraph
Draw a graph using input video metadata. Literally turning your metadata into a whole little chart, main character energy fr.
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.
Example using metadata from signalstats filter:
signalstats,drawgraph=lavfi.signalstats.YAVG:min=0:max=255
Example using metadata from ebur128 filter:
ebur128=metadata=1,adrawgraph=lavfi.r128.M:min=-120:max=5
๐ฒ drawgrid
Draw a grid on the input image. Aesthetic grid moment, we love to see it. ๐ฆ
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,wandheight,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 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,ihandin_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
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 deal as before, it just vibes where it is. โจ
โ๏ธ drawtext
Draw a text string or text from a specified file on top of a video, using the libfreetype library. This is THE text-on-video filter, the icon, the legend. ๐
Heads up, build-flag bestie: to enable compilation of this filter, you need to configure FFmpeg with--enable-libfreetypeand--enable-libharfbuzz. To enable default font fallback and thefontoption you need to configure FFmpeg with--enable-libfontconfig. To enable thetext_shapingoption, you need to configure FFmpeg with--enable-libfribidi. Miss these and the filter simply won't be there, no cap. ๐ญ
Syntax
It accepts the following parameters:
boxโ Used to draw a box around text using the background 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 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. ๐จy_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.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.
Fr fr,strftimeis deprecated โ if you're building something new, clock that and reach fornormalexpansion instead. ๐
fix_boundsโ if true, it checks your text coords and fixes them so nothing gets clipped. no more text hiding behind the edge of the frame ๐fontcolorโ the color used for drawing the fonts. for the syntax of this option, check the "Color" section in theffmpeg-utilsmanual. the default value offontcoloris"black".fontcolor_exprโ a string that gets expanded the same way astextto obtain a dynamicfontcolorvalue. by default this option has an empty value and is not processed. when this option is set, it overrides thefontcoloroption. highkey the glow-up โจfontโ the font family used for drawing text. by defaultSans.fontfileโ the font file used for drawing text. the path must be included. this parameter is mandatory if the fontconfig support is disabled. like, no fontconfig? then this is your only way in, bestie ๐ซถalphaโ draws the text applying alpha blending. the value can be a number between0.0and1.0. the expression accepts the same variablesx,yas well. the default value is1. please seefontcolor_expr. transparency slay ๐fontsizeโ the font size used for drawing text. the default value offontsizeis16.text_shapingโ if set to1, it attempts to shape the text (for example, reverse the order of right-to-left text and join Arabic characters) before drawing it. otherwise, it just draws the text exactly as given. by default1(if supported). respectful of every script fr fr ๐ft_load_flagsโ the flags used for loading the fonts.
the flags map the corresponding flags supported by libfreetype, and are a combination of these values:
defaultno_scaleno_hintingrenderno_bitmapvertical_layoutforce_autohintcrop_bitmappedanticignore_global_advance_widthno_recurseignore_transformmonochromelinear_designno_autohint
the default value is "default".
for more information consult the documentation for the FT_LOAD_* libfreetype flags.
shadowcolorโ the color used for drawing a shadow behind the drawn text. for the syntax of this option, check the "Color" section in theffmpeg-utilsmanual. the default value ofshadowcoloris"black".boxwโ sets the width of the box drawn around the text. the default value ofboxwis computed automatically to match the text width.boxhโ sets the height of the box drawn around the text. the default value ofboxhis computed automatically to match the text height.shadowx,shadowyโ the x and y offsets for the text shadow position with respect to the position of the text. they can be either positive or negative values. the default value for both is"0".start_numberโ the starting frame number for then/frame_numvariable. the default value is"0".tabsizeโ the size in number of spaces used for rendering the tab. default value is4.timecodeโ sets the initial timecode representation in"hh:mm:ss[:;.]ff"format. it can be used with or without thetextparameter. thetimecode_rateoption must be specified. โฐtimecode_rate,rate,rโ sets the timecode frame rate (timecode only). the value will be 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 will wrap around at 24 hours. default is0(disabled). midnight reset energy ๐textโ the text string to be drawn. the text must be a sequence of UTF-8 encoded characters. this parameter is mandatory if no file is specified with the parametertextfile.textfileโ a text file containing 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 parameter text.
if both text and textfile are specified, an error is thrown. pick a lane, bestie ๐ญ
text_sourceโ the text source should be set asside_data_detection_bboxesif you want to use text data in detection bboxes of side data.
if text source is set, text and textfile will be ignored and it will still use text data in detection bboxes of side data. so please do not use this parameter if you are not sure about the text source. like, seriously, only if you know ๐
reloadโ thetextfilewill be reloaded at the specified frame interval. be sure to updatetextfileatomically, or it may be read partially, or even fail. range is0toINT_MAX. default is0.
for real, atomic updates only โ half-written files are giving chaos ๐
x,yโ the expressions which specify the offsets where text will be drawn within the video frame. they are relative to the top/left border of the output image.
the default value of x and y is "0".
see below for the list of accepted constants and functions.
the parameters for x and y are expressions containing the following constants and functions:
darโ input display aspect ratio, it is the same as(w / h) * sarhsub,vsubโ horizontal and vertical chroma subsample values. for example for the pixel format"yuv422p"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 is a positive value, due to 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 is a negative value, due to the grid's orientation, with the Y axis upwards.max_glyph_hโ maximum glyph height, that is the maximum height for all the glyphs contained in the rendered text, it is equivalent toascent - descent.max_glyph_wโ maximum glyph width, that is 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 input frame, starting from0rand(min, max)โ return a random number included between min and max ๐ฒsarโ the input sample aspect ratio.tโ 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 allow the x and y expressions to refer to each other, so you can for example specify "y=x/dar". mutual reference? iconic 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).
๐ธ Text expansion ๐ธ
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. this feature is deprecated in favor of "normal" expansion with the gmtime or localtime expansion functions. like, it still works but it's giving legacy ๐
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 thetextoption 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 thetextfileoption avoids these problems. four layers of escaping is genuinely not the vibe ๐ญ use the file, bestie.
the following functions are available:
expr,eโ the expression evaluation result.
it must take one argument specifying the expression to be evaluated, which accepts the same constants and functions as the x and y values. note that not all constants should be used, for example the text size is not known when evaluating the expression, so the constants text_w and text_h will have an undefined value.
expr_int_format,eifโ evaluate the expression's value and output as formatted integer.
the first argument is the expression to be evaluated, just as for the expr function. the second argument specifies the output format. allowed values are x, X, d and u. they are 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.
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]Nwhich 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]Nwhich 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 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.
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.
Okay so, the first argument? That's the format of the timestamp, and if you don't say anything it just defaults to "flt" โ which is seconds as a decimal number with microsecond accuracy. Then "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, and "localtime" stands for the timestamp of the frame formatted as local time zone time. ๐
The second argument is an offset that gets added to the timestamp. Little nudge, y'know? ๐ซ
If the format is set to "hms", a third argument "24HH" may be supplied to present the hour part of the formatted timestamp in 24h format (00-23). Bestie, 24h format is the superior format, I don't make the rules. ๐
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. ๐
โจ Commands โจ
This filter supports altering parameters via commands:
reinitโ Alter existing filter parameters.
The syntax for the argument is the same as for filter invocation, e.g.
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'
Heads up bestie: if the entire argument can't be parsed or applied as valid values, then the filter will continue with its existing parameters. It does not freak out. It just vibes with what it already had. ๐ซถ
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>
๐ Examples ๐
- 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 size 24 at position x=100 and y=50 (counting from the top-left corner of the screen), text is yellow with a red box around it. Both the text and the box have an opacity of 20%.
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 are not necessary if spaces are not used within the parameter list. ๐
- 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_LINE is 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 CREDITS off the bottom of the frame and scroll up.
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
"strftime"C 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_a and the fontsize value are included in the y offset.
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_basename metadata onto each frame if such metadata exists. Otherwise, plot the string "NA". Note that image2 demuxer must have option
-export_path_metadata 1for the special metadata fields to be available for filters.
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 ๐จ
Draw vector graphics on top of video frames, by executing a script written in a custom language called VGS (Vector Graphics Script). Iconic behaviour honestly. โจ
The documentation for the language can be found in drawvg - Language Reference. A version of this reference with rendered examples can be found at the https://ayosec.github.io/ffmpeg-drawvg/playground/docs/langref.html.
Graphics are rendered using the https://cairographics.org/.
To enable compilation of this filter, you need to configure FFmpeg with --enable-cairo. No cairo, no drawing, them's the rules. ๐ซถ
Parameters
Either "script" or "file" must be set. Like, pick one bestie, you gotta give it something.
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. Literally don't skip this step, the vibes will be off. 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 edgedetect ๐
Detect and draw edges. The filter uses the Canny Edge Detection algorithm. Serving outline realness. โ๏ธ
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.
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". ๐
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๏ธ elbg ๐๏ธ
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 between 0 and UINT32_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.pal8โ Set pal8 output pixel format. This option does not work with codebook length greater than 256. Default is disabled. โ ๏ธuse_alphaโ Include alpha values in the quantization calculation. Allows creating palettized output images (e.g. PNG8) with multiple alpha smooth blending. So pretty. ๐ฆ
๐ entropy ๐
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. Math girl summer fr fr. ๐งฎ
๐ epx ๐
Apply the EPX magnification filter which is designed for pixel art. Retro gamers rise up. ๐พ
It accepts the following option:
nโ Set the scaling dimension:2for"2xEPX",3for"3xEPX". Default is3.
๐ธ eq ๐ธ
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 sets the saturation expression ๐ must be a float in the range0.0to3.0, and the default is"1".gammaโ sets the gamma expression. float, range0.1to10.0, default"1".gamma_rโ sets the gamma expression for red. float, range0.1to10.0, default"1".gamma_gโ sets the gamma expression for green. float, range0.1to10.0, default"1".gamma_bโ sets the gamma expression for blue. float, range0.1to10.0, default"1".gamma_weightโ sets the gamma weight expression โจ this one's lowkey the glow-up saver: it lets you dial back how hard a high gamma value hits the bright parts of the image, so they don't get overamplified and just turn into plain white ๐ญ must be a float in range0.0to1.0.0.0turns gamma correction all the way down,1.0leaves it at full strength. default is"1".evalโ sets when the expressions for brightness, contrast, saturation and gamma get evaluated. it takes these values:initโ only evaluate expressions once, during filter initialization or when a command is processedframeโ evaluate expressions for every incoming frame
default value is init.
The expressions accept the following parameters:
nโ frame count of the input frame, starting from0posโ byte position of the corresponding packet in the input file,NANif unspecified. โ ๏ธ deprecated, do not use, fr frrโ frame rate of the input video,NANif the input frame rate is unknowntโ timestamp expressed in seconds,NANif the input timestamp is unknown
Commands ๐
bestie this filter takes commands too, here's the whole set:
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.
each command accepts the same syntax as its matching option ๐ซถ
and if the expression you hand it isn't valid? it just keeps whatever value it's currently on. no drama, no crash ๐
erosion ๐ชจ
applies an erosion effect to the video โ literally replaces each pixel with the local (3x3) minimum. it accepts these options:
threshold0,threshold1,threshold2,threshold3โ limit the maximum change for each plane. default is65535. if you set0, that plane stays completely unchanged โจcoordinatesโ a flag that says which pixels to refer to. default is255, i.e. all eight pixels get used.
the flags map onto local 3x3 coordinates like this:
1 2 3
4 5
6 7 8
Commands ๐ซ
this filter supports all of the above options as commands.
estdif ๐ฆ
deinterlaces the input video (the name stands for "Edge Slope Tracing Deinterlacing Filter", iykyk). it's a spatial only filter that uses an edge slope tracing algorithm to interpolate the missing lines. it accepts these parameters:
modeโ the interlacing mode to adopt, one of:frameโ output one frame for each framefieldโ output one frame for each field
default value is "field".
parityโ the picture field parity assumed for the input interlaced video, one of:tffโ assume the top field is firstbffโ assume the bottom field is firstautoโ 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, one of:allโ deinterlace all framesinterlacedโ only deinterlace frames marked as interlaced
default value is "all".
rslopeโ search radius for edge slope tracing. default1, allowed range1to15.redgeโ search radius for best edge matching. default2, allowed range0to15.ecostโ edge cost for edge matching. default2, allowed range0to50.mcostโ middle cost for edge matching. default1, allowed range0to50.dcostโ distance cost for edge matching. default1, allowed range0to50.interpโ the interpolation used. default is 4-point interpolation. one of:2pโ two-point interpolation4pโ four-point interpolation6pโ six-point interpolation
Commands ๐ธ
this filter supports the same commands as options.
exposure โ๏ธ
adjusts the exposure of the video stream. options:
exposureโ set the exposure correction in EV. allowed range is-3.0to3.0EV, default value is0EV.blackโ set the black level correction. allowed range is-1.0to1.0, default value is0.
Commands โจ
this filter supports the same commands as options.
extractplanes ๐ง
pulls the color channel components out of the input video stream and into separate grayscale video streams. one option:
planesโ set the plane(s) to extract. the available values are:yuvargb
๐จ picking planes that aren't in the input = error. and that means you literally cannot select"r","g","b"planes at the same time as"y","u","v"planes. no cap.
Examples ๐
- extract the luma, u and v color channel components from an 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 ๐
applies a fade-in/fade-out effect to the input video. 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 where the fade effect starts. default is0.nb_frames,nโ how many frames the fade effect lasts. at the end of the fade-in effect 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 where the fade effect starts. if both start_frame and start_time are 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 effect 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 both duration and nb_frames are specified, duration is used. default is0(nb_frames is used by default).color,cโ the color of the fade. default is"black".
Examples ๐
- fade in the first 30 frames of video:
fade=in:0:30
that 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 ๐
applies the feedback video filter. this one's giving main character energy: it passes cropped input frames to the 2nd output, and from there you can filter them with other video filters. once the filter receives a frame from the 2nd input, that frame gets combined on top of the original frame from the 1st input and passed to the 1st output ๐ซถ
the typical usage is filtering only part of a frame. options:
x,yโ set the top left crop position.w,hโ set the crop size.
Examples โญ
- blur only the top left rectangular part of a video frame of size 100x100 with the
gblurfilter:
[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 of size 100x100 with the
drawboxfilter:
[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 of size 100x100 with the
pixelizefilter:
[in][blurin]feedback=x=320:y=240:w=100:h=100[out][blurout];[blurout]pixelize[blurin]
fftdnoiz ๐
denoises frames using 3D FFT (that's frequency domain filtering, bestie โ different realm entirely). options:
sigmaโ set the noise sigma constant. this sets the denoising strength. default value is1, allowed range is0to30.
โ ๏ธ using very high sigma with low overlap may give you blocking artifacts. be so serious about that.
amountโ set the amount of denoising. by default all detected noise gets reduced. default value is1, allowed range is0to1.blockโ set the size of the block in pixels. default is32, can be8to256.overlapโ set the block overlap. default is0.5, allowed range is0.2to0.8.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 which planes get filtered. by default all available planes are filtered except alpha.
fftfilt ๐๏ธ
applies arbitrary expressions to samples in the frequency domain
dc_Yโ this is the DC value (aka the gain, bestie, it's literally the gain ๐ ) for the luma plane of the image. Takes an integer in range0to1000. Default?0. slay.dc_Uโ same energy, but for the 1st chroma plane. Integer in range0to1000, and the default is0too.dc_Vโ you guessed it ๐: DC value (gain) of the 2nd chroma plane. Integer0to1000, default0.weight_Yโ sets the frequency domain weight expression for the luma plane. yes it's an expression, yes you can be fancy โจweight_Uโ sets the frequency domain weight expression for the 1st chroma plane.weight_Vโ sets the frequency domain weight expression for the 2nd chroma plane.evalโ controls when those expressions get evaluated. lowkey important. it accepts these values:initโ only evaluate expressions once, during filter initialization. one and done ๐ซถframeโ evaluate expressions for each incoming frame. every single one, no skips.
Default value is init.
The filter accepts the following variables:
X,Yโ the coordinates of the current sample ๐W,Hโ the width and height of the imageNโ the number of the input frame, starting from0WS,HSโ the size of the FFT array for horizontal and vertical processing
Examples
- High-pass ๐โจ
fftfilt=dc_Y=128:weight_Y='squish(1-(Y+X)/100)'
- Low-pass ๐ง
fftfilt=dc_Y=0:weight_Y='squish((Y+X)/100-1)'
- Sharpen ๐ฅ
fftfilt=dc_Y=0:weight_Y='1+squish(1-(Y+X)/100)'
- Blur ๐ธ
fftfilt=dc_Y=0:weight_Y='exp(-4 * ((Y+X)/(W+H)))'
field
Okay so this one extracts a single field from an interlaced image, and it does it using stride arithmetic โ that's the whole trick, it avoids wasting CPU time. Iconic efficiency. The output frames are marked as non-interlaced.
The filter accepts the following options:
typeโ specify whether to extract the top field (if the value is0or"top") or the bottom field (if the value is1or"bottom").
fieldhint
This one creates new frames by copying the top and bottom fields from surrounding frames โ and which frames? The numbers come from a hint file ๐
hintโ set the file containing hints: absolute/relative frame numbers.
Here's the deal, bestie: 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 the file can not be out of [N-1,N+1] where N is the current frame number for "absolute" mode, or out of the [-1, 1] range for "relative" mode. First number tells from which frame to pick up the top field, and the second number tells from which frame to pick up the bottom field.
If optionally followed by "+" the output frame will be marked as interlaced. Else if followed by "-" the output frame will be marked as progressive. Else it will be marked the same as the input frame.
If optionally followed by "t" the output frame will use only the top field, or in case of "b" it will use only the bottom field.
If the line starts with "#" or ";" that line is skipped ๐
modeโ can be"absolute"or"relative"or"pattern". Default is"absolute". The"pattern"mode is the same as"relative"mode, except at the last entry of the file, if there are more frames to process than the"hint"file has, it seeks back to the start. loop it ๐
Example of the first several lines of a "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 -
fieldmatch
Field matching filter for inverse telecine โ its whole personality is reconstructing progressive frames from a telecined stream ๐ฌ
Important thing: the filter does not drop duplicated frames. So to achieve a complete inverse telecine, "fieldmatch" needs to be followed by a decimation filter such as decimate in the filtergraph. fr fr, it can't do it alone.
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. see? the split is a feature not a bug ๐
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.
Note that this filter uses the same algorithms as TIVTC/TFM (AviSynth project) and VIVTC/VFM (VapourSynth project). The latter is a light clone of TFM from which "fieldmatch" is based on. While the semantics and usage are very close, some behaviour and option names can differ. iykyk 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
The filter accepts the following options:
orderโ specify 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
Default value is auto.
modeโ set 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 the p/c/n/u/b meaning section.
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 ๐
Default value is pc_n.
ppsrcโ mark the main input stream as a pre-processed input, and enable the secondary input stream as the clean source to pick the fields from. See the filter introduction for more details. It is similar to theclip2feature from VFM/TFM.
Default value is 0 (disabled).
fieldโ set 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 set whether or not chroma is included during the match comparisons. In most cases it is recommended to leave this enabled ๐ซถ 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.
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.y0andy1default to0.scthreshโ set 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]".
Default value is 12.0.
combmatchโ whencombmatchis 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 force"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.
cthresh
okay so cthresh is the area combing threshold for combed frame detection โ basically it's the vibe-check for how strong or visible the combing has to be before the filter is like "yep, that's combed." ๐
Bigger values = combing has to be super obvious to get flagged. Smaller values = the filter is way more sensitive and will catch even faint combing.
Valid settings go from -1 (literally every pixel gets detected as combed, chaotic) all the way up to 255 (no pixel will ever be detected as combed, king of denial). It's basically a pixel difference value, and a good range is [8, 12].
Default is 9.
chroma
sets whether chroma counts toward the combed-frame decision. Bestie, only turn this off if your source has chroma problems (rainbowing, etc.) that are messing with the detection while chroma is enabled. Honestly chroma=0 is usually more reliable โ except for the specific case where the source has chroma-only combing.
Default is 0.
blockx, blocky
these 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 need to be detected as combed before a frame gets declared combed โ peek the combpel description for the details.
Possible values: any number that's a power of 2, starting at 4 and going up to 512.
Default is 16.
combpel
the number of combed pixels inside any of the blocky by blockx size blocks on the frame for the frame to count as combed. So like โ cthresh controls how visible the combing must be, and this one controls how much combing there has to be in any localized area (a window defined by blockx and blocky) on the frame. ๐
Minimum value is 0, maximum is blocky x blockx โ and at that max, no frames will ever be detected as combed. This setting is known as MI in TFM/VFM vocabulary.
Default is 80.
p/c/n/u/b meaning โจ
p/c/n
let's assume this 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
so because of the field matching, we can see some frames get duplicated. To do a complete inverse telecine you need to rely on a decimation filter after this operation โ see for instance the decimate filter.
Same operation but 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 โ 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 bit special, because they match from the opposite parity flag. In the examples below we're assuming we're currently matching the 2nd frame (Top:2, bottom:2). Depending on the match, an 'x' gets placed above and below each matched field. ๐
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
fieldorder
transforms the field order of the input video. iconic little order-flipper ๐ฆ
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 happens by shifting the picture content up or down by one line, then 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 does not alter the incoming video. no notes, no changes, we move. ๐
It's very 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
fillborders
fills the borders of the input video without changing the video stream dimensions. Sometimes video has garbage at the four edges and you don't want to crop the input just to keep the size a multiple of some number. so this is the moment. โจ
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.
mode accepts the following values:
smearโ fill pixels using the outermost pixelsmirrorโ fill pixels using mirroring (half sample symmetric)fixedโ fill pixels with a constant valuereflectโ fill pixels using reflecting (whole sample symmetric)wrapโ fill pixels using wrappingfadeโ fade pixels to a constant valuemarginsโ fill pixels at top and bottom with weighted averages of pixels near the borders
Default is smear.
colorโ set the color for pixels infixedorfademode. Default is black.
Commands
this filter supports the same commands as options, and the command accepts the same syntax as the corresponding option.
If the specified expression isn't valid, it's kept at its current value.
find_rect
finds a rectangular object in the input video. detective mode fr ๐ฅ
The object to search for must be specified as a gray8 image, given via the object option.
For each possible match a score is computed, and 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. (yeah. just one. pick a favourite.)
When an object is found, these metadata entries get 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.
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 the object is not detected. Default is disabled.
Examples
- Cover a rectangular object with 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
floodfill
flood area with values of same pixel components with another values. it's giving paint bucket ๐จ
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.
format
converts 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. team player energy 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".
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
fps ๐ฌ
Converts the video to a specified constant frame rate by duplicating or dropping frames as necessary โ no cap, it just does the thing.
It accepts the following parameters:
fpsโ the desired output frame rate. It takes expressions containing these constants:source_fpsโ the input's frame ratentscโ NTSC frame rate of30000/1001palโ PAL frame rate of25.0filmโ Film frame rate of24.0ntsc_filmโ NTSC-film frame rate of24000/1001
The default is 25.
start_timeโ pretend the first PTS should be the value you give, in seconds. This is what lets you pad/trim at the start of a stream. By default no assumption is made about the first frame's expected PTS, so no padding or trimming happens. For example, you could set this 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 what gets done when reading the last frame. Possible values are:roundโ use the same timestamp rounding method as used for other framespassโ pass through the 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 ๐
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
framepack ๐ฅฝ
Packs 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. Please note that you may conveniently adjust view properties with the scale and fps filters โ bestie behaviour, honestly.
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 otherlinesโ the views are packed by linecolumnsโ the views are packed by columnframeseqโ 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
framerate ๐
Change the frame rate by interpolating new video output frames from the source frames. Glow-up but make it temporal.
Ok so important bestie: 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 shortcuts, iykyk.
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 for flags is:scene_change_detect,scdโ enable scene change detection using the value of the optionscene. This flag is enabled by default.
framestep ๐
Select one frame every N-th frame. Genuinely the simplest filter here and she ate.
This filter accepts the following option:
stepโ select frame after everystepframes. Allowed values are positive integers higher than0. Default value is1.
freezedetect ๐ง
Detect frozen video. Crime scene investigation but for your stream that stopped moving.
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 casedBis 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).
freezeframes ๐ฅถ
Freeze video frames. Like pressing pause on a vibe.
This filter freezes video frames using frame from 2nd input.
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.
frei0r ๐จ
Apply a frei0r effect to the input video. Plugins, but make it video.
To enable the compilation of this filter, you need to install thefrei0rheader and configure FFmpeg with--enable-frei0r. Non-negotiable prerequisite, sorry babes ๐ญ
It accepts the following parameters:
filter_nameโ the name of thefrei0reffect to load. If the environment variableFREI0R_PATHis defined, thefrei0reffect is searched for in each of the directories specified by the colon-separated list inFREI0R_PATH. Otherwise, the standardfrei0rpaths 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 thefrei0reffect.
A frei0r effect parameter can be:
- a boolean (its value is either
yorn) - a double
- a color (specified as
R/G/B, whereR,G, andBare floating point numbers between0.0and1.0, inclusive) or a color description as specified in theColorsection in theffmpeg-utilsmanual - a position (specified as
X/Y, whereXandYare 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 โจ
Commands
This filter supports the filter_params option as commands. You're welcome ๐
fspp โก
Apply fast and simple postprocessing. It is a faster version of spp.
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 โ highkey iconic optimisation 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 is0โ 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).
The flicker warning on use_bframe_qp is real, bestie โ enabling it can cause flicker because B-Frames often have larger QP. Don't say I didn't warn you ๐
fsync ๐บ๏ธ
Synchronize video frames with an external mapping from a file. Fr fr the map is the moment.
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 -
gblur ๐ซง
Apply Gaussian blur filter. Soft focus era, we love her.
The filter accepts the following options:
sigmaโ set horizontal sigma, standard deviation of Gaussian blur. Default is0.5.stepsโ how many steps the Gaussian approximation gets. default is1.planesโ which planes get filtered. literally all of them by default, bestie.sigmaVโ vertical sigma, and if you hand it a negative number it just copies whateversigmais. default is-1.
Commands
This filter is down with commands the same way it's down with options โ the command speaks the exact same syntax as the matching option. ๐
If the expression you typed is not valid, no panic: it just stays at its current value. living its truth.
geq
Apply a generic equation to each pixel. yes really, every single pixel. math girl summer. ๐ฅ
The filter accepts the following options:
lum_expr,lumโ set the luma expression.cb_expr,cbโ set the chrominance blue expression.cr_expr,crโ set the chrominance red expression.alpha_expr,aโ set the alpha expression.red_expr,rโ set the red expression.green_expr,gโ set the green expression.blue_expr,bโ set the blue expression.
The colorspace gets picked based on whatever options you actually specified. If one of lum_expr, cb_expr, or cr_expr is in play, the filter automatically selects a YCbCr colorspace. If one of red_expr, green_expr, or blue_expr is in play, it selects an RGB colorspace instead. slay, it just knows. โจ
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 evaluate to the luma expression. the way it has a whole backup plan ๐ญ
The expressions can use the following 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. E.g. for YUV4:2:0 the values are1,1for the luma plane, and0.5,0.5for chroma planes.Tโ time of the current frame, expressed in seconds.p(x, y)โ return the value of the pixel at location (x,y) of the current plane.lum(x, y)โ return the value of the pixel at location (x,y) of the luma plane.cb(x, y)โ return 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 return 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 return 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), which lets you obtain sums of samples within a rectangle. See the functions without thesumpostfix. so basically the same icons but with receipts ๐interpolationโ set 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. it's not mad, it's just helpful ๐ซถ
Please note that this filter can use multiple threads, in which case each slice will have its own expression state. If you want to use only a single expression state because your expressions depend on previous state, then you should limit the number of filter threads to 1. bestie read that twice, it's important ๐
Examples
- Flip the image horizontally:
geq=p(W-X\,Y)
- Generate a bidimensional sine wave, with angle
PI/3and a wavelength of100pixels:
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 is the same size as the input (also see the
vignettefilter):
geq=lum=255*gauss((X/W-0.5)*3)*gauss((Y/H-0.5)*3)/gauss(0)/gauss(0),format=gray
gradfun
Fix the banding artifacts that sometimes sneak into nearly flat regions when you truncate to 8-bit color depth. It interpolates the gradients that should go where the bands are, and dithers them. banding? never heard of her. ๐ฆ
It is designed for playback only. Do not use it prior to lossy compression, because compression tends to lose the dither and bring back the bands. so do not come for me when it doesn't work, I warned you ๐ญ
It accepts the following 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 the 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 will fall back to the default value):
gradfun=radius=8
graphmonitor
Show various filtergraph stats. it's giving dashboard, it's giving observability ๐
With this filter you can debug a complete filtergraph. Especially issues with links filling up with queued frames. we love a diagnostic icon.
The filter accepts the following options:
size,sโ set video output size. Default ishd720.opacity,oโ set video opacity. Default is0.9. Allowed range is from0to1.mode,mโ set 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 set 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 the 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 the above two values.disabledโ show the timeline filter status.
rate,rโ set upper limit for video rate of output stream. Default value is25. This guarantees that the output video frame rate will not be higher than this value. a little ceiling, as a treat ๐
grayworld
A color constancy filter that applies color correction based on the grayworld assumption. no cap, it's just out here fixing your colors ๐
The algorithm uses linear light, so input data should be linearized beforehand (and possibly correctly tagged). do the prep work bestie, it matters 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. it's the science-y sibling of the one above ๐ง
See: https://staff.science.uva.nl/th.gevers/pub/GeversTIP07.pdf
The filter accepts the following options:
diffordโ the order of differentiation to be applied on the scene. Must be chosen in the range[0,2]and the default value is1.minknormโ the Minkowski parameter to be used for calculating the Minkowski distance. Must be chosen in the range[0,20]and the default value is1. Set to0for getting the max value instead of calculating the Minkowski distance. icon behavior honestly.sigmaโ the standard deviation of Gaussian blur to be applied on the scene. Must be chosen in the range[0,1024.0]and the default value =1.floor( sigma * break_off_sigma(3) )can't be equal to0ifdiffordis greater than0. yes that's a real constraint, I don't make the rules ๐
Examples
- Grey Edge:
greyedge=difford=1:minknorm=5:sigma=2
- Max Edge:
greyedge=difford=1:minknorm=0:sigma=2
guided
Apply guided filter for edge-preserving smoothing, dehazing and so on. smoothing but make it smart โจ
The filter accepts the following options:
radiusโ set the box radius in pixels. Allowed range is1to20. Default is3.epsโ set regularization parameter (with square). Allowed range is0to1. Default is0.01.modeโ set filter mode. Can bebasicorfast. Default isbasic.subโ set subsampling ratio forfastmode. Range is2to64. Default is4. No subsampling occurs inbasicmode.guidanceโ set guidance mode. Can beofforon. Default isoff. Ifoff, a single input is required. Ifon, two inputs of the same resolution and pixel format are required. The second input serves as the guidance. team work makes the dream work ๐ซถplanesโ set planes to filter. Default is first only.
Commands
This filter supports all of the above options as commands. yes, all of them, go off ๐
Examples
- Edge-preserving smoothing with guided filter:
ffmpeg -i in.png -vf guided out.png
- ๐ซถ Dehazing, structure-transferring filtering, detail enhancement with guided filter. For generating the guidance image, bestie, go read the paper "Guided Image Filtering". See:
http://kaiminghe.com/publications/pami12guidedfilter.pdf.
ffmpeg -i in.png -i guidance.png -filter_complex guided=guidance=on out.png
๐ haldclut ๐
Okay so haldclut applies a Hald CLUT to a video stream. The first input is the video stream to process, and the second one is the Hald CLUT. That Hald CLUT input can be a simple picture or a whole complete video stream.
The filter accepts these options:
clutโ sets which CLUT video frames will be processed from the second input stream. It can befirstorall. Default isall.shortestโ forces termination when the shortest input terminates. Default is0.repeatlastโ keeps applying the last CLUT after the end of the stream. A value of0disables the filter after the last frame of the CLUT is reached. Default is1.
haldclut also has the same interpolation options as lut3d โ both filters share the same internals, iykyk.
This filter also supports the framesync options.
More info about the Hald CLUT lives on Eskil Steenberg's website (Hald CLUT author) at http://www.quelsolaar.com/technology/clut.html.
๐ฎ Commands ๐ฎ
This filter supports the interp option as commands.
๐ Workflow examples ๐
๐ฌ Hald CLUT video stream
Generate an identity Hald CLUT stream altered with 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
๐ Note: make sure you use a lossless codec.
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
The Hald CLUT will be applied to the 10 first seconds (duration of clut.nut), then the latest picture of that CLUT stream will be applied to the remaining frames of the mandelbrot stream.
๐ Hald CLUT with preview
A Hald CLUT is supposed to be a squared image of Level*Level*Level by Level*Level*Level pixels. For a given Hald CLUT, FFmpeg will select the biggest possible square starting at the top left of the picture. The remaining padding pixels (bottom or right) will be ignored. This area can be used to add a preview of the Hald CLUT.
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 the same color bars processed by the color changes.
Then, the effect of this Hald CLUT can be visualized with:
ffplay input.mkv -vf "movie=clut.png, [in] haldclut"
๐ฆ hflip ๐ฆ
Flip the input video horizontally. That's it, that's the vibe.
For example, to horizontally flip the input video with ffmpeg:
ffmpeg -i in.avi -vf "hflip" out.avi
๐ธ histeq ๐ธ
This filter applies a global color histogram equalization on a per-frame basis.
It can be used to correct video that has a compressed range of pixel intensities. The filter redistributes the pixel intensities to equalize their distribution across the intensity range. It may be viewed as an "automatically adjusting contrast filter". This filter is useful only for correcting degraded or poorly captured source video.
The filter accepts these options:
strengthโ determines the amount of equalization to be applied. As the strength is reduced, the distribution of pixel intensities more-and-more approaches that of the input frame. The value must be a float number in the range[0,1]and defaults to0.200.intensityโ sets the maximum intensity that can generated and scales the output values appropriately. The strength should be set as desired and then the intensity can be limited if needed to avoid washing-out. The value must be a float number in the range[0,1]and defaults to0.210.antibandingโ sets the antibanding level. If enabled, the filter will randomly vary the luminance of output pixels by a small amount to avoid banding of the histogram. Possible values arenone,weakorstrong. It defaults tonone.
๐ histogram ๐
Compute and draw a color distribution histogram for the input video.
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. It shows the distribution of the Y, U, V, A or R, G, B components, depending on the input format, in the current frame. Below each graph a color component scale meter is shown.
The filter accepts these options:
level_heightโ sets height of level. Default value is200. Allowed range is[50, 2048].scale_heightโ sets height of color scale. Default value is12. Allowed range is[0, 40].display_modeโ sets display mode. It accepts these 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 theparade, except that the graphs representing color components are superimposed directly over one another. Default isstack.
levels_modeโ sets mode. Can be eitherlinear, orlogarithmic. Default islinear.componentsโ sets what color components to display. Default is7.fgopacityโ sets foreground opacity. Default is0.7.bgopacityโ sets background opacity. Default is0.5.colors_modeโ sets colors mode. It accepts these values:whiteonblackblackonwhitewhiteongrayblackongraycoloronblackcoloronwhitecolorongrayblackoncolorwhiteoncolorgrayoncolor
Default is whiteonblack.
โจ Examples โจ
- Calculate and draw histogram:
ffplay -i input -vf histogram
โจ hqdn3d โจ
This is a high precision/quality 3d denoise filter. It aims to reduce image noise, producing smooth images and making still images really still. It should enhance compressibility.
It accepts these optional parameters:
luma_spatialโ a non-negative floating point number which specifies spatial luma strength. It defaults to4.0.chroma_spatialโ a non-negative floating point number which specifies spatial chroma strength. It defaults to3.0*luma_spatial/4.0.luma_tmpโ a floating point number which specifies luma temporal strength. It defaults to6.0*luma_spatial/4.0.chroma_tmpโ a floating point number which specifies chroma temporal strength. It defaults toluma_tmp*chroma_spatial/luma_spatial.
๐ฎ Commands ๐ฎ
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.
๐พ hwdownload ๐พ
Download hardware frames to system memory.
The input must be in hardware frames, and the output a non-hardware format. Not all formats will be supported on the output โ it may be necessary to insert an additional format filter immediately following in the graph to get the output in a supported format. No cap, this part matters.
๐บ๏ธ hwmap ๐บ๏ธ
Map hardware frames to system memory or to another device.
This filter has several different modes of operation; which one is used depends on the input and output formats:
- Hardware frame input, normal frame output โ map the input frames to system memory and pass them to the output. If the original hardware frame is later required (for example, 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 โ that is, return the original hardware frame. Otherwise, a device must be provided. Create new hardware surfaces on that device for the output, then map them back to the software format at the input and give those frames to the preceding filter. This will then act like the
hwuploadfilter, but may be able to avoid an additional copy when the input is already in a compatible format. - 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 this is system-dependent, but typically it means that they must refer to the same underlying hardware context (for example, 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, as the original contents of the frame need not be loaded.directโ the mapping must not involve any copying. Indirect mappings to copies of frames are created in some cases where either direct mapping is not possible or it would have unexpected properties. Setting this flag ensures that the mapping is direct and will fail if that is not possible.
Defaults to read+write if not specified.
derive_devicetype โ rather than using the device supplied at initialisation, instead 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 โ 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.
โ ๏ธ Heads up bestie โ this one is dangerous. It can break the filter that came right before it in undefined ways if that filter has any extra constraints on its output. Do not touch it unless you fully understand the implications. Like, fr fr. ๐
๐ผ๏ธ hwupload
Uploads your system-memory frames up onto hardware surfaces. Slay. โจ
The device you're uploading to has to be supplied when the filter is initialised. If you're running through ffmpeg, pick the right device with the -filter_hw_device option, or with the derive_device option. Your 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've gotta refer to the same underlying hardware context (think: same graphics card, iykyk).
Extra parameters it accepts:
derive_device typeโ instead of using the device handed over at initialisation, derive a brand-new device of type type from the device that the input frames are already living on. Cute, right? ๐
๐ hwupload_cuda
Uploads system-memory frames to a CUDA device.
Accepts these optional parameters:
deviceโ the number of the CUDA device to use.
๐ง hqx
Applies a high-quality magnification filter built specifically for pixel art. This one was originally created by Maxim Stepin โ icon behavior, honestly. ๐
Accepts this option:
nโ set the scaling dimension:2forhq2x,3forhq3x, and4forhq4x. Default is3.
๐ hstack
Stacks your input videos horizontally. Side by side, bestie. ๐ซถ
Every stream has to be the same pixel format and the same height.
Ngl, this filter is faster than doing the same thing with theoverlayandpadfilters to build the same output.
Options:
inputsโ set the number of input streams. Default is2.shortestโ if set to1, force the output to terminate the moment the shortest input terminates. Default value is0.
๐ธ hsvhold
Turns a certain HSV range into gray values.
Here's the vibe: this filter measures the color difference between the HSV color you set in the options and the ones it actually measures in the video stream. Depending on your options, output colors can be changed to gray โ or not. Your call. ๐
Options:
hueโ set the hue value used in the color difference calculation. Allowed range is from-360to360. Default value is0.satโ set the saturation value used in the color difference calculation. Allowed range is from-1to1. Default value is0.valโ set the value used in the color difference calculation. Allowed range is from-1to1. Default value is0.similarityโ set the similarity percentage with the key color. Allowed range is from0to1. Default value is0.01.0.00001matches only the exact key color, while1.0matches literally everything.blendโ blend percentage. Allowed range is from0to1. Default value is0.0.0makes pixels either fully gray, or not gray at all. 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.
Same energy as above โ it measures the color difference between the HSV color you set in the options and the ones it measures in the video stream. Depending on your options, output colors can be made transparent by adding an alpha channel. โจ
Options:
hueโ set the hue value used in the color difference calculation. Allowed range is from-360to360. Default value is0.satโ set the saturation value used in the color difference calculation. Allowed range is from-1to1. Default value is0.valโ set the value used in the color difference calculation. Allowed range is from-1to1. Default value is0.similarityโ set the similarity percentage with the key color. Allowed range is from0to1. Default value is0.01.0.00001matches only the exact key color, while1.0matches everything.blendโ blend percentage. Allowed range is from0to1. Default value is0.0.0makes pixels either fully transparent, or not transparent at all. Higher values result in semi-transparent pixels, with a higher transparency the more similar the pixel's color is to the key color.
๐ hue
Modifies the hue and/or the saturation of the input. Main character filter energy, honestly. ๐
Accepts these parameters:
hโ specify the hue angle as a number of degrees. Accepts an expression, defaults to0.sโ specify the saturation in the[-10,10]range. Accepts an expression and defaults to1.Hโ specify the hue angle as a number of radians. Accepts an expression, defaults to0.bโ specify the brightness in the[-10,10]range. Accepts an expression and defaults to0.
handHare mutually exclusive โ you literally cannot specify both at the same time. Pick a lane bestie. ๐
The b, h, H and s option values are expressions containing these 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
- Set the hue to 90 degrees and the saturation to 1.0:
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 0 and 2 over a period of 1 second:
hue="H=2*PI*t: s=sin(2*PI*t)+1"
- Apply a 3 second saturation fade-in effect starting at 0:
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 3 second saturation fade-out effect starting at 5 seconds:
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))"
๐ ๏ธ Commands
This filter supports these commands:
bshHโ modify the hue and/or the saturation and/or the brightness of the input video. The command accepts the same syntax as the corresponding option. If the specified expression isn't valid, it's kept at its current value. No drama. ๐ซถ
๐ huesaturation
Applies hue-saturation-intensity adjustments to the input video stream.
Important: this filter operates in RGB colorspace.
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 gonna be adjusted. You set this by providing one or multiple values, so you 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 the strength of filtering. Allowed range is from0to100. Default value is1.rw,gw,bwโ set the weight for each RGB component. Allowed range is from0to1. By default it's set to0.333,0.334,0.333. These options get used in the saturation and lightness processing.lightnessโ set preserving lightness, disabled by default. Adjusting hues can change lightness from the original RGB triplet; with this option enabled, lightness is kept at the same value. ๐
๐ hysteresis
Grows the first stream into the second stream by connecting components. Sounds unhinged, but it makes it possible to build more robust edge masks. Slay.
Options:
planesโ set which planes get processed as a bitmap; unprocessed planes get copied from the first stream. Default value0xfโ all planes get processed.thresholdโ set the threshold used in filtering. If a pixel component value is higher than this value, the filter algorithm for connecting components kicks in. By default the value is0.
The hysteresis filter also supports the framesync options. ๐ง
๐ iccdetect
Detects the colorspace from an embedded ICC profile (if there is one), and updates the frame's tags to match accordingly.
Options:
forceโ if true, the frame's existing colorspace tags will always be overridden by the values detected from an ICC profile. Otherwise they'll only be assigned if they contain"unknown". Enabled by default.
๐จ iccgen
Generates ICC profiles and attaches them to frames.
Options:
color_primariescolor_trcโ configure the colorspace that the ICC profile will be generated for. The default value of"auto"infers the value from the input frame's metadata, defaulting to BT.709/sRGB as appropriate. Check out thesetparamsfilter for a list of possible values, but note that"unknown"values are not valid for this filter.forceโ if true, an ICC profile will be generated even if it would overwrite an already existing ICC profile. Disabled by default.
๐ช identity
Obtains the identity score between two input videos.
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 both inputs have the same number of frames, which get compared one by one.
The obtained per component, average, min and max identity score gets printed through the logging system.
The filter stores the calculated identity scores of each frame in frame metadata. ๐
It also supports the framesync options.
In the example below, the input file main.mpg being processed is compared against the reference file ref.mpg:
ffmpeg -i main.mpg -i ref.mpg -lavfi identity -f null -
๐ idet
Detects the video interlacing type.
This filter tries to detect whether the input frames are interlaced, progressive, top field first, or bottom field first. It'll also try to detect fields that are repeated between adjacent frames โ which is a sign of telecine, if you were wondering.
Single frame detection considers only immediately adjacent frames when it classifies each frame. Multiple frame detection incorporates the classification history of the previous frames. Two different vibes, both valid. ๐
The filter logs these metadata values:
single.current_frameโ detected type of the current frame using single-frame detection. One of:tff'' (top field first),bff'' (bottom field first),progressive'', orundetermined''single.tffโ cumulative number of frames detected as top field first using single-frame detection.multiple.tffโ cumulative number of frames detected as top field first using multiple-frame detection.single.bffโ cumulative number of frames detected as bottom field first using single-frame detection.multiple.current_frameโ detected type of the current frame using multiple-frame detection. One of:tff(top field first),bff(bottom field first),progressive, orundetermined.multiple.bffโ cumulative number of frames detected as bottom field first using multiple-frame detection.single.progressiveโ cumulative number of frames detected as progressive using single-frame detection.multiple.progressiveโ cumulative number of frames detected as progressive using multiple-frame detection.single.undeterminedโ cumulative number of frames that could not be classified using single-frame detection.multiple.undeterminedโ cumulative number of frames that could not be classified using multiple-frame detection.repeated.current_frameโ which field in the current frame is repeated from the last. One ofneither,top, orbottom.repeated.neitherโ cumulative number of frames with no repeated field.repeated.topโ cumulative number of frames with the top field repeated from the previous frame's top field.repeated.bottomโ cumulative number of frames with the bottom field repeated from the previous frame's bottom field.
The filter accepts the following options, bestie:
intl_thresโ sets the interlacing threshold.prog_thresโ sets the progressive threshold.rep_thresโ the threshold for repeated field detection.half_lifeโ number of frames after which a given frame's contribution to the statistics is halved (i.e., it contributes only0.5to its classification). The default of0means that all frames seen are given full weight of1.0forever.analyze_interlaced_flagโ when this is not0thenidetwill use the specified number of frames to determine if the interlaced flag is accurate, and it will not count undetermined frames. If the flag is found to be accurate it will be used without any further computations; if it's found to be inaccurate it will be cleared without any further computations. This allows inserting theidetfilter as a low computational method to clean up the interlaced flag.
โจ Examples โจ
Wanna inspect the field order of the first 360 frames in a video, in verbose detail? Say less:
ffmpeg -i INPUT -filter:v idet,metadata=mode=print -frames:v 360 -an -f null -
The idet filter will add analysis metadata to each frame, which will then be discarded. At the end, the filter will also print a final report with statistics. obsessed โ you get the receipts AND the cleanup.
๐ il
Deinterleave or interleave fields โ literally what it says on the tin.
This filter lets you process interlaced image fields without deinterlacing them. Deinterleaving splits the input frame into 2 fields (so-called half pictures). Odd lines get moved to the top half of the output image, even lines to the bottom half. You can process (filter) them independently and then re-interleave them. iconic separation behavior โจ
The filter accepts the following options:
luma_mode,lchroma_mode,calpha_mode,a
Available values for luma_mode, chroma_mode and alpha_mode are:
noneโ do nothing.deinterleave,dโ deinterleave fields, placing one above the other.interleave,iโ interleave fields. Reverse the effect of deinterleaving.
Default value is "none".
luma_swap,lschroma_swap,csalpha_swap,as
Swap luma/chroma/alpha fields. Exchanges even & odd lines. Default value is 0.
Commands
This filter supports the all above options as commands. ๐
๐ซง inflate
Apply the inflate effect to the video.
This filter replaces the pixel by the local (3x3) average, but only taking into account values higher than the pixel. It's giving selective glow-up, no cap.
It accepts the following options:
threshold0threshold1threshold2threshold3
Limit the maximum change for each plane. Default is 65535. If 0, the plane will remain unchanged.
Commands
This filter supports the all above options as commands.
๐ง interlace, interlace_vulkan
Simple interlacing filter from progressive contents. This interleaves upper (or lower) lines from odd frames with lower (or upper) lines from even frames, halving the frame rate and preserving image height.
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 this determines whether the interlaced frame is taken from the even (tffโ default) or odd (bff) lines of the progressive frame.lowpassโ vertical lowpass filter to avoid twitter interlacing and reduce moire patterns.0,offโ disable vertical lowpass filter.1,linearโ enable linear filter (default).2,complexโ enable complex filter. This will slightly less reduce twitter and moire, but better retain detail and the subjective sharpness impression.
๐ธ kerndeint
Deinterlace input video by applying Donald Graft's adaptive kernel deinterlacing. Works on the interlaced parts of a video to produce progressive frames โ surgical, honestly.
The description of the accepted parameters follows.
threshโ set the threshold which affects the filter's tolerance when determining if a pixel line must be processed. It must be an integer in the range[0,255]and defaults to10. A value of0will result in applying the process on every pixel.mapโ paint pixels exceeding the threshold value to white if set to1. Default is0.orderโ set the field order. Swap fields if set to1, leave fields alone if0. Default is0.sharpโ enable additional sharpening if set to1. Default is0.twowayโ enable twoway sharpening if set to1. Default is0.
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
๐ฆ kirsch
Apply the kirsch operator to the input video stream. Edge detection but make it fashion โจ
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 value which will be multiplied with the filtered result.deltaโ set value which will be added to the filtered result.
Commands
This filter supports the all above options as commands.
๐ lagfun
Slowly update darker pixels.
This filter makes short flashes of light appear longer โ the drama is extended, respectfully. This filter accepts the following options:
decayโ set factor for decaying. Default is.95. Allowed range is from0to1.planesโ set which planes to filter. Default is all. Allowed range is from0to15.
Commands
This filter supports the all above options as commands.
๐ lenscorrection
Correct radial lens distortion.
This filter can be used to correct for radial distortion as can result from the use of wide angle lenses, and thereby re-rectify the image. To find the right parameters one can use tools available for example as part of opencv, or simply trial-and-error. To use opencv, use the calibration sample (under samples/cpp) from the opencv sources and extract the k1 and k2 coefficients from the resulting matrix.
Note that effectively the same filter is available in the open-source tools Krita and Digikam from the KDE project. iykyk
In contrast to the vignette filter, which can also be used to compensate lens errors, this filter corrects the distortion of the image, whereas vignette corrects the brightness distribution โ so you may want to use both filters together in certain cases, though you will have to take care of ordering, i.e. whether vignetting should be applied before or after lens correction.
Options
The filter accepts the following options:
cxโ relative x-coordinate of the focal point of the image, and thereby the center of the distortion. This value has a range[0,1]and is expressed as fractions of the image width. Default is0.5.cyโ relative y-coordinate of the focal point of the image, and thereby the center of the distortion. This value has a range[0,1]and is expressed as fractions of the image height. Default is0.5.k1โ coefficient of the quadratic correction term. This value has a range[-1,1].0means no correction. Default is0.k2โ coefficient of the double quadratic correction term. This value has a range[-1,1].0means no correction. Default is0.iโ set interpolation type. Can be"nearest"or"bilinear". Default is"nearest".fcโ specify the color of the unmapped pixels. For the syntax of this option, check the"Color"section in theffmpeg-utilsmanual. Default color is"black@0".
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 half of the image diagonal and r_src and r_tgt are the distances from the focal point in the source and target images, respectively.
Commands
This filter supports the all above options as commands.
๐ lensfun
Apply lens correction via the lensfun library (http://lensfun.sourceforge.net/).
The lensfun filter requires the camera make, camera model, and lens model to apply the lens correction. The filter will load the lensfun database and query it to find the corresponding camera and lens entries in the database. As long as these entries can be found with the given options, the filter can perform corrections on frames. Note that incomplete strings will result in the filter choosing the best match with the given options, and the filter will output the chosen camera and lens models (logged with level "info"). You must provide the make, camera model, and lens model as they are required. no skipping the homework on this one ๐
ok so to get a list of available makes and models, you just leave out one or both of the make and model options โ the filter will yeet the full list into the log at level INFO. Column one is the make, column two is the model. ๐
And if you want the lens list, set any values for make and model and leave out the lens_model option โ boom, full list of lenses in the log, again at level INFO. Heads up: the ffmpeg tool will literally exit right after the list is printed. Like, it's done, it's leaving. ๐ซถ
The filter accepts these options, bestie:
makeโ the make of the camera (for example,"Canon"). This option is required.modelโ the model of the camera (for example,"Canon EOS 100D"). This option is required.lens_modelโ the model of the lens (for example,"Canon EF-S 18-55mm f/3.5-5.6 IS STM"). This option is required.db_pathโ the full path to the lens database folder. If you don't set it, the filter will try to load the database from the install path from when the library was built. Default is unset.modeโ the type of correction to apply. Valid values are:vignettingโ enables fixing lens vignetting.geometryโ enables fixing lens geometry. This is the default.subpixelโ enables fixing chromatic aberrations.vig_geoโ enables fixing lens vignetting and lens geometry.vig_subpixelโ enables fixing lens vignetting and chromatic aberrations.distortionโ enables fixing both lens geometry and chromatic aberrations.allโ enables all possible corrections. the whole menu, no skips. ๐
focal_lengthโ the focal length of the image/video (that's the zoom; expected to be constant for video). For example, an 18--55mm lens has a focal length range of [18--55], so pick a value in that range when you're using that lens. Default18.apertureโ the aperture of the image/video (again, expected constant for video). ngl, aperture is only used for vignetting correction. Default3.5.focus_distanceโ the focus distance of the image/video (expected constant for video). This one is only used for vignetting, and it only slightly affects the vignetting correction process. If you don't know it, just leave it at the default (which is1000).scaleโ the scale factor applied after transformation. After correction the video is no longer necessarily rectangular, so 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 is done. Lower values may show you more of the corrected image, higher values may avoid unmapped areas in the output. pick your fighter ๐target_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, apply it). un-correcting, iconic behaviour ๐ญinterpolationโ the type of interpolation used when correcting distortion. Valid options are:nearestlinear(default)lanczos
Examples ๐
- 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
- Apply the same as before, but only for the first 5 seconds of video. cute little snack-sized correction โจ
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
lcevc ๐ฆ
Low Complexity Enhancement Video Codec filter, built on liblcevc_dec (https://github.com/v-novaltd/LCEVCdec).
libplacebo ๐ฅ
Flexible GPU-accelerated processing filter, built on libplacebo (https://code.videolan.org/videolan/libplacebo).
Options ๐
The options for this filter are split into the following sections:
Output mode ๐ฌ
These options control the overall output mode. By default, libplacebo will try 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 the source frames.
inputsโ set the number of inputs. This can be used, alongside theidxvariable, to let you place/blend multiple inputs inside the output frame. Basically it gives you hstack, overlay, etc. energy. ๐ซถw,hโ set the output video dimension expression. Default values areiwandih. Allows for the same expressions as the scale filter.crop_x,crop_yโ set the input crop x/y expressions, default values are(iw-cw)/2and(ih-ch)/2.crop_w,crop_hโ set the input crop width/height expressions, default values areiwandih.pos_x,pos_yโ set the output placement x/y expressions, default values are(ow-pw)/2and(oh-ph)/2.pos_w,pos_hโ set the output placement width/height expressions, default values areowandoh.rotateโ rotate the input frame clockwise by the specified angle. Your options:0,36090180270
fpsโ set the output frame rate. This can be rational, e.g.60000/1001. If you set it to the special string"none"(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 your specified target framerate, in a manner as determined by theframe_mixeroption.formatโ set the output format override. If unset (the default), frames are output in the same format as the respective input frames. Otherwise, format conversion gets performed.force_original_aspect_ratio,force_divisible_byโ work exactly the same as the identical scale filter 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 ones from, like, anamorphic video sources โ get 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. Mutually exclusive withfit_mode. Disabled by default.pad_crop_ratioโ specifies a ratio (between 0.0 and 1.0) 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, giving you a mix of the two approaches. bestie's blender settings ๐fit_modeโ specify the content fit strategy according to a list of predefined modes. Determines how the input image is 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 this option is mutually exclusive withnormalize_sar. Defaults tofill. Valid values: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 either"contain"or"none", depending on whether the input is larger than the output or not.
fit_senseโ whenfit_modeis in use, this controls how the fit strategy is applied against the specified output resolution. Mutually exclusive withforce_original_aspect_ratio. Valid values: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 from 0.0 to 1.0, 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: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 fully replaces the conversion from the image color space to the output color space. If such a LUT is present, it has the highest priority, and overrides any ICC profiles, as well as options related to tone mapping and output colorimetry (color_primaries,color_trc). Periodt ๐extra_optsโ pass extra libplacebo internal configuration options. These can be specified as a list ofkey=valuepairs separated by:. The following example shows how to configure 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 that libplacebo will use to store and load cached shader objects. This cache is not cleaned up automatically. If the path does not end in a directory separator, the generated filenames will be effectively prefixed by the last path component. All directories must already exist.
-vf "libplacebo=shader_cache=/tmp/pl-shader-"
colorspace,color_primaries,color_trc,range,chroma_locationโ configure the colorspace that output frames will be delivered in. The default value ofautooutputs frames in the same format as the input frames, leading to no change. For any other value, conversion will be performed.
See the setparams filter for a list of possible values. ๐ฆ
alpha_modeโ choose the desired output alpha mode, when the output format has an alpha channel. See thesetparamsfilter for a list of possible values.apply_filmgrainโ apply film grain (e.g. AV1 or H.274) if present in source frames, and strip it from the output. Enabled by default. โจapply_dolbyvisionโ apply Dolby Vision RPU metadata if present in source frames, and strip it from the output. Enabled by default. Note that Dolby Vision will always outputBT.2020+PQ, overriding the usual input frame metadata. These will also be picked as the values ofautofor the respective frame output options.
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 the following constants:
in_idx,idxโ the (0-based) numeric index of the currently active input stream.crop_w,cw/crop_h,chโ the computed values ofcrop_wandcrop_h.pos_w,pw/pos_h,phโ the computed values ofpos_wandpos_h.in_t,tโ the input frame timestamp, in seconds.NANif input timestamp is unknown.out_t,otโ the input frame timestamp, in seconds.NANif input timestamp is unknown.nโ the input frame number, starting with0.
โจ Scaling โจ
The options in this section control how libplacebo performs upscaling and (if necessary) downscaling. Note that libplacebo will always internally operate on 4:4:4 content, so any sub-sampled chroma formats such as yuv420p will necessarily be upsampled and downsampled as part of the rendering process. That means scaling might be in effect even if the source and destination resolution are the same. ๐ญ lowkey important
upscaler,downscalerโ configure the filter kernel used for upscaling and downscaling. The respective defaults arespline36andmitchell. For a full list of possible values, passhelpto 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.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, 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. This is also popularly referred to as just"Jinc scaling". Slow but very high quality. ๐gaussianโ Gaussian kernel. Has certain ideal mathematical properties, but subjectively very blurry.mitchellโ cubic BC spline with parameters recommended by Mitchell and Netravali. Very little ringing.
frame_mixerโ controls the kernel used for mixing frames temporally. The default value isnone, which disables frame mixing. For a full list of possible values, passhelpto this option. The most important values are: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 is blended according to the relative overlap. This is the recommended option whenever preserving the original subjective appearance is desired.mitchell_clampโ larger filter kernel that smoothly interpolates multiple frames in a manner designed to eliminate ringing and other artefacts as much as possible. This is the recommended option wherever maximum visual smoothness is desired.linearโ linear blend/fade between frames. Especially useful for constructing e.g. slideshows.
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. Disabled by default.sigmoidโ enable sigmoidal compression during upscaling. Reduces ringing slightly. Enabled by default. ๐
โจ Deinterlacing โจ
Deinterlacing is automatically supported when frames are tagged as interlaced, however frames are not deinterlaced unless a deinterlacing algorithm is chosen.
deinterlaceโ the deinterlacing algorithm to use.weaveโ no deinterlacing, weave fields together into a single frame. This is the default.bobโ naive bob deinterlacing, simply repeat 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 skip the spatial deinterlacing check when usingyadifdeinterlacing.send_fieldsโ output 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 does not contain any interlaced frames. Disabled by default. ๐
โจ Debanding โจ
Libplacebo comes with a built-in debanding filter that is good at counteracting many common sources of banding and blocking. Turning this on is highly recommended whenever quality is desired. ๐ซถ
debandโ enable (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 lead to 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. Defaults to6.0.
โจ Color adjustment โจ
A collection of subjective color controls. Not very rigorous, so the exact effect will vary somewhat depending on the input primaries and colorspace.
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 will rotate the UV subvector, defaulting to BT.709 coefficients for RGB inputs.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).conesโ cone model to use for color blindness simulation. Accepts any combination ofl,mands. Here are 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.
โจ Peak detection โจ
To help deal with sources that only have static HDR10 metadata (or no tagging whatsoever), libplacebo uses its own internal frame analysis compute shader to analyze source frames and adapt the tone mapping function in realtime. If this is too slow, or if exactly reproducible frame-perfect results are needed, it's recommended to turn this feature off.
peak_detectโ enable HDR peak detection. Ignores staticMaxCLL/MaxFALLvalues in favor of dynamic detection from the input. Note that the detected values do not get written back to the output frames, they merely guide the internal tone mapping process. Enabled by default. ๐ฅsmoothing_periodโ the peak-detection smoothing period, somewhere between0.0and1000.0. Higher values make peak detection less responsive to changes in the input โ like, it stops freaking out every frame. Defaults to20.0๐scene_threshold_low,scene_threshold_highโ the lower and upper thresholds for scene change detection, expressed on a logarithmic scale between0.0and100.0. They default to1.0and3.0respectively. Set either one to a negative value and this whole functionality is disabled, no cap ๐ธpercentileโ which percentile of the frame brightness histogram gets used as the source peak for tone-mapping. Defaults to99.995, a pretty conservative value (sensible queen behaviour tbh). Setting it to100.0disables frame histogram measurement entirely and instead uses the true peak brightness for tone-mapping. iykyk ๐
Tone mapping ๐จ
The options in this section control how libplacebo performs tone-mapping and gamut-mapping when it's dealing with mismatches between wide-gamut or HDR content. In general, libplacebo relies on accurate source tagging and mastering display gamut information to produce the best results โ so tag your sources properly, bestie, it literally matters ๐
gamut_modeโ how to handle out-of-gamut colors that can occur as a result of colorimetric gamut mapping. The options are:clipโ do nothing, simply 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 โจrelativeโ relative colorimetric hard-clip. Similar to"perceptual"but without the soft knee.saturationโ saturation mapping, maps primaries directly to primaries in RGB space. Not recommended except for artificial computer graphics for which a bright, saturated display is desired ๐absoluteโ 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 ๐ฌdarkenโ 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). Great for debugging, cursed for watching.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 ๐
tonemappingโ the 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 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 the reinhard tone 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 like"clip", while values near0.0make this curve behave like"reinhard". The default value is0.3, which provides a good balance between colorimetric accuracy and preserving out-of-gamut details ๐hableโ 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 to"reinhard"with 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 ๐ญ 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 of"tonemapping". The default value of0.0is replaced by the curve's 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 with"peak_detect"๐ซถcontrast_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 when"contrast_recovery"is disabled.
Dithering ๐ฆ
By default, libplacebo will dither whenever necessary, which includes rendering to any integer format below 16-bit precision. It's recommended to always leave this on, since not doing so may result in visible banding in the output โ even if the "debanding" filter is enabled ๐ญ If maximum performance is needed, use "ordered_fixed" instead of disabling dithering. (That's the move. Trust.)
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. โจorderedโ 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.
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.
Debugging / performance โก
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 โ think of it as the "gaming mode" of the filter, bestie ๐
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 ๐ฅ (Yes, really. Almost everything stops working. Maximum speed though.)
Commands ๐
This filter supports almost all of the above options as commands. Slay โ you can tweak stuff at runtime, no restart needed 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:
- Feelin' fancy with frame mixing? Slap on
fps=60:frame_mixer=mitchell_clamp:
libplacebo=fps=60:frame_mixer=mitchell_clamp
- Wanna convert your input to standard sRGB JPEG? Say less:
libplacebo=format=yuv420p:colorspace=bt470bg:color_primaries=bt709:color_trc=iec61966-2-1:range=pc
- Higher quality debanding settings, for when you're extra:
libplacebo=deband=true:deband_iterations=3:deband_radius=8:deband_threshold=6
- Run this filter on the CPU on systems with Mesa installed (with the most expensive options turned off, bestie, we're budgeting):
ffmpeg ... -init_hw_device vulkan:llvmpipe ... -vf libplacebo=upscaler=none:downscaler=none:peak_detect=false
- Suppress the CPU-based AV1/H.274 film grain application in the decoder so this filter handles it instead. Lowkey important note: this is only a gain if the frames are already on the GPU, or if you're using
libplacebofor other purposes โ otherwise the VRAM roundtrip will more than offset any speedup you were hoping for. ๐ญ
ffmpeg -export_side_data +film_grain ... -vf libplacebo=apply_filmgrain=true
- Interop with VAAPI hwdec so you don't round-trip through RAM (the glow-up we deserve):
ffmpeg -init_hw_device vulkan -hwaccel vaapi -hwaccel_output_format vaapi ... -vf libplacebo
๐ libvmaf ๐
Calculate the VMAF (Video Multi-Method Assessment Fusion) score for a reference/distorted pair of input videos. It's giving โจquality judgeโจ.
The first input is the distorted video, and the second input is the reference video.
The VMAF score you get is printed through the logging system.
It requires Netflix's vmaf library (libvmaf) as a pre-requisite. Once you've installed the library, you can enable it using: ./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_v0.6.1"featureโ a|delimited list of features. Each feature can be configured with a number of parameters.log_pathโ set the file path to be used to store log files.log_fmtโ set the format of the log file (xml,json,csv, orsub).poolโ set the pool method to be used for computing vmaf. Options are"min","harmonic_mean"or"mean"(default).n_threadsโ set number of threads to be used when initializing libvmaf. Default value:0, no threads.n_subsampleโ set frame subsampling interval to be used.
This filter also supports the framesync options.
โจ Examples โจ
- In the examples below, a distorted video
distorted.mpgis compared with a reference filereference.mpg. - Basic usage, no drama:
ffmpeg -i distorted.mpg -i reference.mpg -lavfi libvmaf=log_path=output.xml -f null -
- Example with multiple models (go off, king):
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 ๐
This is the CUDA variant of the libvmaf filter. It only accepts CUDA frames โ that's the whole vibe check.
It requires Netflix's vmaf library (libvmaf) as a pre-requisite. Once you've installed the library, you can enable it using: ./configure --enable-nonfree --enable-ffnvcodec --enable-libvmaf.
โจ Examples โจ
- 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 -
๐ฆ limitdiff ๐ฆ
Apply limited difference filter using second and optionally third video stream. Very "spot the difference but make it scientific".
The filter accepts the following options:
thresholdโ set the threshold to use when allowing certain differences between video streams. Any absolute difference value lower or exact than this threshold will pick pixel components from the first video stream.elasticityโ set the elasticity of soft thresholding when processing video streams. This value multiplied with the first one sets the second threshold. Any absolute difference value greater or exact than 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 enable the reference (third) video stream processing. By default it's disabled. If set, this video stream will be used for calculating absolute difference with the first video stream.planesโ specify which planes will be processed. Defaults to all available.
Commands
This filter supports all the above options as commands, except option reference. (Not me excluding reference from the command squad ๐
)
๐ limiter ๐
Limits the pixel component values to the specified range [min, max]. Keeping everyone in their lane, respectfully.
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 specify which planes will be processed. Defaults to all available.
Commands
This filter supports all the above options as commands.
๐ฅ loop ๐ฅ
Loop video frames. It's giving rewind-the-TikTok energy.
The filter accepts the following options:
loopโ set the number of loops. Setting this value to-1will result in infinite loops. Default is0.sizeโ set maximal size in number of frames. Default is0.startโ set first frame of loop. Default is0.timeโ set the time of loop start in seconds. Only used if the option namedstartis set to-1.
โจ Examples โจ
- Loop single first frame infinitely (periodt):
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
๐ธ lut1d ๐ธ
Apply a 1D LUT to an input video. Iconic lil colour transform.
The filter accepts the following options:
fileโ set the 1D LUT file name.
Currently supported formats:
cubeโ Iridascspโ cineSpace
interpโ select interpolation mode.
Available values are:
nearestโ use values from the nearest defined point.linearโ interpolate values using the linear interpolation.cosineโ interpolate values using the cosine interpolation.cubicโ interpolate values using the cubic interpolation.splineโ interpolate values using the spline interpolation.
Commands
This filter supports all the above options as commands.
๐ lut3d ๐
Apply a 3D LUT to an input video. The big sister of lut1d, no cap.
The filter accepts the following options:
fileโ set the 3D LUT file name.
Currently supported formats:
3dlโ AfterEffectscubeโ Iridasdatโ DaVincim3dโ Pandoracspโ cineSpace
interpโ select 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.
๐ซถ lumakey ๐ซถ
Turn certain luma values into transparency. Bye-bye, luma. ๐
The filter accepts the following options:
thresholdโ set the luma which will be used as base for transparency. Default value is0.toleranceโ set the range of luma values to be keyed out. Default value is0.01.softnessโ set 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 ๐
Compute a look-up table for binding each pixel component input value to an output value, and apply it to the input video.
lutyuv applies a lookup table to a YUV input video, lutrgb to an RGB input video.
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.
The exact component associated to each of the c* options depends on the format in input.
The lut filter requires either YUV or RGB pixel formats in input, lutrgb requires RGB pixel formats in input, and lutyuv requires YUV. (Read the dress code, bestie ๐)
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 expression"maxval-clipval+minval".clip(val)โ the computed value inval, 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 expression"pow((clipval-minval)/(maxval-minval)\,gamma)*(maxval-minval)+minval"
All expressions default to "clipval".
Commands
This filter supports the same commands as options.
โจ Examples โจ
- Negate input video:
- crush the colors into their opposites โ negating via
maxval+minval-valis literally the same energy as just sayingnegval, bestie, the long way is just for the girlies who like to see the math:
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"
which is, and I cannot stress this enough, the exact same thing as:
lutrgb="r=negval:g=negval:b=negval"
lutyuv="y=negval:u=negval:v=negval"
- negate just the luma โ one line, no notes ๐
lutyuv=y=negval
- yeet the chroma, go full grayscale โ u and v get pinned to 128 and the color just... leaves the chat. iconic honestly:
lutyuv="u=128:v=128"
- luma burn effect โ double the value, let it glow ๐ฅ
lutyuv="y=2*val"
- no green, no blue, only vibes โ red stays, everything else is deleted:
lutrgb="g=0:b=0"
- set a flat alpha channel on your input โ needs the rgba format first, she's specific like that:
format=rgba,lutrgb=a="maxval-minval/2"
- gamma-correct the luma by 0.5 โ half the gamma, all of the slay:
lutyuv=y=gammaval(0.5)
- throw away the least significant bits of luma โ yes the bitmask is
128+64+32, keep it exactly, and yes the single quotes matter:
lutyuv=y='bitand(val, 128+64+32)'
- technicolor glam โ push u and v out from the midpoint, very 1960s movie musical:
lutyuv=u='(val-maxval/2)*2+maxval/2':v='(val-maxval/2)*2+maxval/2'
lut2, tlut2 ๐
Okay so lut2 is the two-input girly ๐ โ she takes two input streams and gives you back exactly one output stream.
Meanwhile tlut2 (the time lut2, iykyk) doesn't want two streams at all โ she takes two consecutive frames from one single stream. Main character behavior.
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, and this one corresponds to the alpha componentdโ set output bit depth, only available for thelut2filter. By default it's0, which means the bit depth is automatically picked from the first input format.
Also: lut2 supports the framesync options too, no cap ๐ซถ
Each of these bad boys specifies the expression used to compute the lookup table for the corresponding pixel component values.
Which component actually goes with which c* option? Depends on the format in the inputs, babes. It's giving "read the room / read the pixel format".
The expressions can contain the following constants:
w,hโ the input width and heightxโ the first input value for the pixel componentyโ the second input value for the pixel componentbdxโ the first input video bit depthbdyโ the second input video bit depth
All expressions default to x. periodt.
Commands ๐ฌ
This filter supports all the above options as commands except option d. (She's not like the other options.)
Examples โจ
- 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 ๐ธ
Clamp the first input stream with the second input and third input stream. Three streams, one clamp, very "hold my hand so I don't go out of bounds" energy.
She returns the value of the first stream, squeezed to live between second input stream โ 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; the unprocessed planes get copied straight from the first stream. By default the value is0xf, which means all planes get processed. all of them. every single one. ๐
Commands
This filter supports all the above options as commands.
maskedmax ๐
Merge the second and third input stream into the output stream using absolute differences between the second input stream and the first input stream, plus the absolute difference between the third input stream and the first input stream. The picked value comes from the second input stream if the second absolute difference is greater than the first one โ otherwise it comes from the third input stream. She's dramatic but she's fair.
This filter accepts the following options:
planesโ set which planes will be processed as bitmap; unprocessed planes get copied from the first stream. By default0xf, all planes are processed.
Commands
This filter supports all the above options as commands.
maskedmerge ๐ฆ
Merge the first input stream with the second input stream using per-pixel weights in the third input stream. Yes, the third stream is the boss here, we're just blending.
A value of 0 in the third stream pixel component means that pixel component from the first stream is returned unchanged. The maximum value (e.g. 255 for 8-bit videos) means that pixel component from the second stream is returned unchanged. Intermediate values define the amount of merging between both input stream's pixel components. It's a gradient, bestie, not a switch.
This filter accepts the following options:
planesโ set which planes will be processed as bitmap; unprocessed planes get copied from the first stream. By default0xf, all planes are processed.
Commands
This filter supports all the above options as commands.
maskedmin ๐ง
Merge the second and third input stream into the output stream using absolute differences between the second input stream and the first input stream, and the absolute difference between the third input stream and the first input stream. The picked value comes from the second input stream if the second absolute difference is less than the first one โ otherwise it comes from the third input stream. (Same as maskedmax but she flipped the comparison, as one does.)
This filter accepts the following options:
planesโ set which planes will be processed as bitmap; unprocessed planes get copied from the first stream. By default0xf, all planes are processed.
Commands
This filter supports all the above options as commands.
maskedthreshold โญ
Pick pixels by comparing the absolute difference of two video streams against a fixed threshold.
So: if the absolute difference between the pixel component of the first and second video stream is equal to or lower than the threshold you supplied, then the pixel component from the first video stream is picked. Otherwise the pixel component from the second video stream is picked. Simple as.
This filter accepts the following options:
thresholdโ set the threshold used when picking pixels from the absolute difference of the two input video streams.planesโ set which planes will be processed as bitmap; unprocessed planes get copied from the second stream (yes, second this time, keep up ๐). By default0xf, all planes are processed.modeโ set the mode of filter operation. Can beabsordiff. Default isabs.
Commands
This filter supports all the above options as commands.
maskfun ๐
Create a mask from the input video.
For example, it's useful to create motion masks after the tblend filter. Very "I made this for you" of her.
This filter accepts the following options:
lowโ set low threshold. Any pixel component lower than or exactly equal to this value will be set to0.highโ set high threshold. Any pixel component higher than this value will be set to the max value allowed for the 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 the frame. If the sum of all pixel components is higher than this average, the output frame will be completely filled with the value set by thefilloption. Typically useful for scene changes when used in combination with thetblendfilter. ๐
Commands
This filter supports all the above options as commands.
mcdeint ๐
Apply motion-compensation deinterlacing.
Heads up though: she needs one field per frame as input, and must therefore be used together with yadif=1/3 or an equivalent. No solo acts, she's a duet girlie.
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 uses 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 the 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 ๐
Pick the median pixel from a certain rectangle defined by radius. Democracy, but for pixels.
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, the value will be picked from the horizontalradiusoption. (She'll share, but only if you make her.)percentileโ set the median percentile. Default value is0.5. A default value of0.5will always pick median values, while0will pick minimum values, and1maximum values.
Commands
This filter supports the same commands as options. 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 crash, no drama, she just stays where she is. ๐ซถ
mergeplanes ๐
Merge color channel components from several video streams.
The filter accepts up to 4 input streams, and merges the selected input planes into the output video. It's a group project and she's the one actually doing the work.
This filter accepts the following options:
mappingโ set the input to output plane mapping. Default is0.
The mapping 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 mapping is similar: Bb describes the mapping for the output stream's second plane, Cc describes the mapping for the output stream's third plane, and Dd describes the mapping for the output stream's fourth plane. It's giving hex code, but make it planes. ๐
formatโ set output pixel format. Default isyuva444p.map0s,map1s,map2s,map3sโ set the input to output stream mapping for output Nth plane. Default is0.map0p,map1p,map2p,map3pโ set the input to output plane mapping for output Nth plane. Default is0.
Examples ๐
- Merge three gray video streams of the same width and height into a single video stream:
[a0][a1][a2]mergeplanes=0x001020:yuv444p
- Merge the 1st
yuv444pstream and the 2nd gray video stream into ayuva444pvideo stream:
[a0][a1]mergeplanes=0x00010210:yuva444p
- Swap Y and A plane in a
yuva444pstream: - Swap U and V plane in
yuv420pstream:
format=yuv420p,mergeplanes=0x000201:yuv420p
- Cast a
rgb24clip toyuv444p:
format=rgb24,mergeplanes=0x000102:yuv444p
๐ mestimate
Okay so this one estimates motion vectors using block matching algorithms and then exports them โ the vectors get stashed in frame side data so other filters can use them later. Bestie, it's literally giving "I did the math so you don't have to" ๐
This filter accepts the following options:
methodโ pick your motion estimation method. Accepted values are: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
Same energy as mestimate but make it GPU โจ This one estimates and exports motion vectors using D3D12 hardware-accelerated motion estimation. It leans on the GPU hardware motion estimation capabilities hanging out in the DirectX 12 Video APIs, which gets you significant performance improvements over the software-based mestimate filter. No cap, that's a glow-up.
Motion vectors are stored in frame side data to be used by other filters.
Heads up though: this filter requires the input to be in d3d12 hardware pixel format. And it uses quarter-pixel precision for motion vector estimation โ fancy.
This filter accepts the following options:
mb_sizeโ Macroblock size. Only8and16are supported. Default16.
Examples
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
Apply Midway Image Equalization effect using two video streams. ๐ซถ
So what even is that? Midway Image Equalization adjusts a pair of images so they have the same histogram, while keeping their dynamics as much as possible โ like, preserving the vibes of each image while matching them up. It's useful for e.g. matching exposures from a pair of stereo cameras. Iconic for stereo work, fr fr.
This filter has two inputs and one output, which must be of same pixel format, but may be of different sizes. The output of filter is first input adjusted with midway histogram of both inputs. (Yes, the first one โ remember that ๐)
This filter accepts the following option:
planesโ Set which planes to process. Default is15, which is all available planes.
๐ซ minterpolate
Convert the video to specified frame rate using motion interpolation. Smooth motion hours, basically โจ
This filter accepts the following options:
fpsโ Specify the output frame rate. This can be rational e.g.60000/1001. Frames are dropped if fps is 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. Scene change detection replace 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.
๐ธ mix
Mix several video input streams into one video stream. A whole friend group, blended into one 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 number of weights is smaller than number of frames last specified weight will be used for all remaining unset weights.scaleโ Specify scale, if it is set it will be multiplied with sum of each weight multiplied with pixel values to give 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.
๐ค monochrome
Convert video to gray using custom color filter. Grayscale but make it couture ๐
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 the all above options as commands.
๐ง morpho
This filter allows to apply main morphological grayscale transforms, erode and dilate with arbitrary structures set in second input stream.
And like โ unlike naive implementation and much slower performance in erosion and dilation filters, when speed is critical morpho filter should be used instead. So if you're in a hurry, bestie, pick this one. ๐โโ๏ธ๐จ
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. Yes, it literally just throws frames away when they're basically twins ๐ฏโโ๏ธ
The main use of this filter is for very-low-bitrate encoding (e.g. streaming over dialup modem), 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 to start dropping them. If the value is0, the frame is dropped disregarding the number of previous sequentially similar frames.
Default value is 0.
hilofracโ 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.
โญ msad
Obtain the MSAD (Mean Sum of Absolute Differences) between two input videos. It's a comparison filter, bestie โ it's giving "who wore it better" but with math ๐ฅ
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.
Fr fr, mismatch the resolution or pixel format and things get weird โ this filter is picky about its matchups.
The obtained per component, average, min and max MSAD is printed through the logging system.
The filter stores the calculated MSAD of each frame in frame metadata.
This filter also supports the framesync options.
okay so real quick, bestie: in this example the input file main.mpg being processed is literally being compared with the reference file ref.mpg.
ffmpeg -i main.mpg -i ref.mpg -lavfi msad -f null -
multiply
Multiply the first video stream's pixel values by the second video stream's pixel values. It's giving math but make it cinema โจ
The filter accepts these options:
scaleโ sets the scale applied to the second video stream. Default is1. Allowed range is from0to9.offsetโ sets the offset applied to the second video stream. Default is0.5. Allowed range is from-1to1.planesโ specifies which planes from the input video stream get processed. By default all planes are processed.
Commands
This filter supports the same commands as options. ๐
negate
Negate/invert the input video. Main character energy, but flipped ๐ญ
It accepts this option:
componentsโ sets which components to negate.
Available values for components are:
yuvargb
negate_alphaโ with value1, it negates the alpha component if present. Default value is0.
Commands
This filter supports the same commands as options. ๐ซถ
nlmeans
Denoise frames using the Non-Local Means algorithm. No cap, this one is lowkey iconic for cleaning up noisy footage.
Each pixel is adjusted by looking for other pixels with similar contexts. This context similarity is defined by comparing their surrounding patches of size pxp. Patches are searched in an area of rxr around the pixel.
Note that the research area defines centers for patches, which means some patches will be made of pixels outside that research area. ๐ง
The filter accepts these 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 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 chroma planes. The default value is0and means automatic.
nnedi
Deinterlace video using neural network edge directed interpolation. It's giving smart-girl deinterlacing ๐ฅ
This filter accepts these options:
weightsโ mandatory option; without the binary file the filter can not 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 isall. Can beallorinterlaced.fieldโ set 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 size of 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 are blended together to compute the final output value. Can befast, default, orslow.etypeโ set which set of weights to use in the predictor.
Can be one of the following:
a,absโ weights trained to minimize absolute error.s,mseโ weights trained to minimize squared error.
pscrnโ controls whether or not the prescreener neural network is 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. ๐ฆ
noformat
Force libavfilter not to use any of the specified pixel formats for the input to the next filter. It's the "girl, not that format" filter 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, but make it aesthetic ๐ธ
The filter accepts these 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 pattern.tโ 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)
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.
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. Obsessed with the flexibility, honestly ๐
The normalize filter accepts these options:
blackpt,whiteptโ colors which define the output range. The minimum input value is mapped toblackpt. The maximum input value is mapped towhitept. The defaults are black and white respectively. Specifying white forblackptand black forwhiteptwill 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.smoothingโ 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. No notes, just vibes ๐
ocio
OpenColorIO library filter. This filter lets you 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 these 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-v2.1, which specifies one of the built-in defaults.inputโ 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 it goes from a display/view to the "input colorspace".filetransformโ lets you point at an external file-transform instead of the OCIO config file. It's lowkey useful for applying a single transform without needing a whole OCIO config file. โจformatโ lets you specify the outputpix_fmtof the OCIO filter. This has to be a RGB colorspace, so bestie, you really are limited torgb24,rgba,rgb48,rgba48,gbrp10,gbrp12,gbrpf32le,gbrapf32leโ for most encoding we'd recommendrgb48. ๐context_paramsโ lets you specify additional context parameters for the OCIO filter. It's a list ofkey=valuepairs, separated by colons.
Examples ๐ซ
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 this assumes the OCIO file is defined with the OCIO environment variable. Note you will need to wrap the argument in quotes to ensure that the spaces are interpreted correctly.
input=ACEScg:display=sRGB - Display:view=ACES 1.0 - SDR Video:format=rgb48
As above, but using the OCIO file studio-config-v1.0.0_aces-v1.3_ocio-v2.1_ns.ocio rather than 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 will want to set the color matrix for the conversion. This is a good example of combining the two.
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 โ Optical Character Recognition ๐
This filter uses Tesseract for optical character recognition. To enable compilation of this filter, you need to configure FFmpeg with --enable-libtesseract. ๐ง
It accepts the following options:
datapathโ set datapath to 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. The filter exports confidence of recognized words as the frame metadata lavfi.ocr.confidence. ๐
ocv ๐ผ๏ธ
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 information: http://docs.opencv.org/master/modules/imgproc/doc/filtering.html
Several libopencv filters are supported; see the following subsections. ๐
dilate ๐ฅ
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, the number or columns and rows of the read file are assumed instead.
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 ๐ชจ
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.
smooth ๐งด
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 the following 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 ๐
2D Video Oscilloscope.
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 ๐
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 ๐ธ
- Inspect full first row of video frame.
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 ๐ซถ
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.
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).eof_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,W,main_h,Hโ the main input width and height.overlay_w,w,overlay_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"hsubis 2 andvsubis 1.nโ the number of input frame, starting from 0posโ the position in the file of the input frame,NANif unknown; deprecated, do not usetโ 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.
You can chain together more overlays but you should test the efficiency of such approach. ๐
Commands โจ
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 ๐
- Draw the overlay at 10 pixels from the bottom right corner of the main video:
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 ffmpeg tool with the
-filter_complexoption: - Insert 2 different transparent PNG logos (second logo chilling in the bottom right corner) using the ffmpeg tool:
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 โ and bestie,
WxHhas to specify the size of the main input to the overlay filter, no cap:
color=color=red@.3:size=WxH [over]; [in][over] overlay [out]
- Play an original video and a filtered version side by side (here we're using the
deshakefilter) with the ffplay tool:
ffplay input.avi -vf 'split[a][b]; [a]pad=iw*2:ih[src]; [b]deshake[filt]; [src][filt]overlay=w'
The above command is literally the same as:
ffplay input.avi -vf 'split[b], pad=iw*2[src], [b]deshake, [src]overlay=w'
- Make a sliding overlay that appears from the left to the right top part of the screen, starting since time 2 โ iconic entrance behavior tbh:
overlay=x='if(gte(t,2), -w+(t-2)*20, NAN)':y=0
- Compose output by putting two input videos side to side โ a whole collab:
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 sneaky little redaction moment:
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 layers on layers, we love a stacked fit:
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 ๐
Apply Overcomplete Wavelet denoiser. Say bye to the grain, bestie โจ
The filter accepts the following options:
depthโ Set depth.
Larger depth values will denoise lower frequency components more, but slow down filtering. So like, more glow-up, more waiting, iykyk.
Must be an int in the range 8-16, default is 8.
luma_strength,lsโ Set luma strength.
Must be a double value in the range 0-1000, default is 1.0.
chroma_strength,csโ Set chroma strength.
Must be a double value in the range 0-1000, default is 1.0.
๐ pad ๐
Add paddings to the input image, and place the original input at the provided x, y coordinates. It's giving "frame it, bestie" ๐ผ๏ธ
It accepts the following parameters:
width,wโheight,h
Specify an expression for the size of the output image with the paddings added. If the value for width or height is 0, the corresponding input size is used for the output.
The width expression can reference the value set by the height expression, and vice versa. Mutual support, we love to see it ๐
The default value of width and height is 0.
xโy
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. Cute little auto-center moment โจ
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_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/ihsarโ input sample aspect ratiodarโ input display aspect ratio, it is the same as(iw / ih) * sarhsub,vsubโ The horizontal and vertical chroma subsample values. For example for the pixel formatyuv422phsubis2andvsubis1.
๐ธ Examples ๐ธ
- Add paddings with the color
violetto the input video. The output video size is640x480, and the top-left corner of the input video is placed at column0, row40:
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 ๐จ
Generate one palette for a whole video stream. It's giving curator energy, fr fr ๐
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 be black. (So like, the leftovers just sit there in black, humble and unseen ๐ค)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. Main character = whatever's moving ๐singleโ 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.
๐ฆ Examples ๐ฆ
- Generate a representative palette of a given video using ffmpeg:
ffmpeg -i input.mkv -vf palettegen palette.png
๐ paletteuse ๐
Use a palette to downsample an input video stream. Glow-down, but make it art ๐จ
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. (An icon of questionable choices, we respect the archival moment ๐)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 processrectangleโ 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). Efficiency queen ๐
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.
๐ Examples ๐
- 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 ๐
Correct perspective of video not recorded perpendicular to the screen. (Filmed it at a whole angle? Not anymore bestie, we're straightening that vibe out ๐โจ)
Okay so here's the whole rundown of the params it takes ๐
x0,y0,x1,y1,x2,y2,x3,y3โ these set the coordinate expressions for the top left, top right, bottom left and bottom right corners. Default values are"0:0:W:0:0:H:W:H", and with those the perspective just... stays exactly the same, no cap. If the"sense"option is"source", then the points you specified get sent to the corners of the destination. If"sense"is"destination", then it's the other way around โ the corners of the source get sent to the coordinates you gave.
The expressions can use these variables:
W,Hโ the width and height of the video frame.inโ input frame count.onโ output frame count.
interpolationโ sets the interpolation used for the perspective correction.
It accepts these values:
linearcubic
Default value is linear.
senseโ sets how the coordinate options get interpreted, bestie.
It accepts these values:
0,sourceโ send the point in the source that's 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.
evalโ tells it when to evaluate the expressions for the coordinatesx0,y0,...x3,y3.
It accepts these values:
initโ only evaluate the expressions once, during filter initialization, or when a command gets processed.frameโ evaluate the expressions for every single incoming frame.
Default value is init.
๐ phase
Delays interlaced video by one field time so that the field order actually flips. Slay.
The intended use? Fixing PAL movies that were captured with the opposite field order to the film-to-video transfer. Like, a rescue mission ๐ซถ
Here's what it accepts:
modeโ sets the phase mode.
It accepts these 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' documentation has something to refer to โ but if you actually select it, the filter will faithfully do nothing. Iconic behaviour, honestly ๐aโ capture field order determined automatically by field flags, transfer opposite. The filter picks betweentandbmodes frame by frame using field flags. If no field information is available, then this works just likeu.uโ capture unknown or varying, transfer opposite. The filter picks betweentandbframe by frame by analyzing the images and selecting whichever alternative 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.Uโ both capture and transfer unknown or varying. The filter picks betweent,bandpusing image analysis only.
Commands ๐ฌ
This filter supports the all above options as commands.
โก photosensitivity
Reduces the various flashes in video, so it helps out users with epilepsy. Genuinely a good-vibes filter ๐
It accepts these 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.
๐ฌ pixdesctest
Pixel format descriptor test filter โ mainly useful for internal testing, ngl. The output video should be equal to the input video.
For example:
format=monow, pixdesctest
can be used to test the monowhite pixel format descriptor definition.
๐จ pixelize
Applies pixelization to the video stream. Aesthetic โจ
The filter accepts these options:
width,w,height,hโ set the block dimensions that get 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 ๐ฌ
This filter supports all options as commands.
๐ pixscope
Displays sample values of color channels. Mainly useful for checking color and levels. Minimum supported resolution is 640x480 โ don't try to be cute with anything smaller.
The filters accept these 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 ๐ฌ
This filter supports same commands as options.
๐๏ธ pp7
Applies 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 these options:
qpโ force a constant quantization parameter. It accepts an integer in range0to63. If you don't set it, the filter will use the QP from the video stream (if available).modeโ set the 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).
๐ซง premultiply
Applies an alpha premultiply effect to the input video stream, using the first plane of the second stream as alpha.
Both streams must have same dimensions and same pixel format. No exceptions, bestie.
The filter accepts this option:
planesโ set which planes will be processed; unprocessed planes will be copied. By default value0xf, all planes will be processed.inplaceโ don't require the 2nd input for processing, instead use the alpha plane from the input stream.
๐ premultiply_dynamic
Dynamically premultiplies or unpremultiplies 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.
The filter accepts this option:
planesโ set which planes will be processed; unprocessed planes will be copied. By default value0xf, all planes will be processed.
๐ง prewitt
Applies the prewitt operator to the input video stream.
The filter accepts these options:
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 ๐ฌ
This filter supports the all above options as commands.
๐ pseudocolor
Alters frame colors in the video with pseudocolors. It's giving glow-up ๐
This filter accepts these 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 it's 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.
The expressions can contain these 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 ๐ฌ
This filter supports the all above options as commands.
Examples โจ
- 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
Obtains the average, maximum and minimum PSNR (Peak Signal to Noise Ratio) between two input videos.
This filter takes 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 PSNR.
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, which get compared one by one. So like, keep them matched or it's gonna be a mess ๐ญ
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's 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.
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 tells the filter whether to write that max value into the stats log. Default is0, and it needsstats_version>= 2. If you set it whilestats_version< 2, the filter just returns an error. no cap. ๐ญ
This filter also supports the framesync options. ๐ซถ
The file printed if stats_file is selected? It's a whole sequence of key/value pairs, written as key:value, one for each compared couple of frames.
And if you specify a stats_version greater than 1, a header line comes before the list of per-frame-pair stats, with key value pairs following the frame format, with these parameters:
psnr_log_versionโ the version of the log file format. Will matchstats_version. โจfieldsโ a comma separated list of the per-frame-pair parameters included in the log.
A description of each shown per-frame-pair parameter, bestie, coming right up:
nโ sequential number of the input frame, starting from 1.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
- 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. iconic ๐
- 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 -
pullup
Pulldown reversal (inverse telecine) filter โ it can handle mixed hard-telecine, 24000/1001 fps progressive, and 30000/1001 fps progressive content. she's versatile ๐
The pullup filter is built to take advantage of future context when it makes its decisions. It's stateless in the sense that it doesn't lock onto a pattern to follow โ instead it looks forward to the following fields so it can identify matches and rebuild progressive frames. lowkey genius.
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.
The 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 of 8 pixels, while top and bottom are in units of 2 lines. The default is 8 pixels 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. ๐ง
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 ...
qp
Change video quantization parameters (QP). โจ
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
- Some equation like:
qp=2+2*sin(PI*qp)
qrencode
Generate a QR code using the libqrencode library (see https://fukuchi.org/works/qrencode/), and overlay it on top of the current frame. okay this one is genuinely so fun ๐
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 overlaid. ๐
This filter accepts the following options:
qrcode_width,qandpadded_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.
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.
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 an higher correction level, the encoding size will increase but the code will be more robust to corruption. Lower level isL.
It accepts the following values:
LMQH
expansionโ Select how the input text is expanded. Can be eithernone, ornormal(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,bcandforeground_color,fcโ Set the QR code and background color. The default value offoreground_colorisblack, the default value ofbackground_coloriswhite.
For the syntax of the color options, check the Color section in the ffmpeg-utils manual.
๐ฆ qrencode Expressions
The expressions set by the options contain the following constants and functions.
darโ input display aspect ratio, it is the same as(w / h) * sardurationโ the current frame's duration, in secondshsub,vsubโ horizontal and vertical chroma subsample values. For example for the pixel formatyuv422phsubis2andvsubis1.main_h,Hโ the input heightmain_w,Wโ the input widthnโ the number of input frame, starting from0pict_typeโ a number representing the picture typeqr_w,wโ the width of the encoded QR coderendered_qr_w,qandrendered_padded_qr_w,Qโ the width of the rendered QR code, without and without padding.
These parameters allow the q and Q expressions to refer to each other, so you can for example specify q=3/4*Q.
rand(min, max)โ return a random number included between min and maxsarโ the input sample aspect ratiotโ timestamp expressed in seconds,NANif the input timestamp is unknownx,yโ the x and y offset coordinates where the text is drawn.
These parameters allow the x and y expressions to refer to each other, so you can for example specify y=x/dar.
๐ธ qrencode Text expansion
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 thetextoption in the filter argument string and as the filter argument in the filtergraph description, and possibly also for the shell โ that makes up to four levels of escaping. Using a text file with thetextfileoption avoids these problems. ๐ญ seriously, four levels.
The following functions are available:
n,frame_numโ return the frame numberptsโ 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.
okay so, the qrencode text-expansion functions keep going like this, bestie:
expr_formatted,efโ Evaluate the expression's value and output as a formatted string. The first argument is the expression to be evaluated, just as for theexprfunction. The second argument specifies the output format. Allowed values arex,X,dandu. They are treated exactly as in theprintffunction. 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.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]Nwhich 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]Nwhich 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 empty. Available metadata can be identified by inspecting entries starting withTAGincluded within each frame section printed by runningffprobe -show_frames. String metadata generated in filters leading to the qrencode filter are also available.rand(min, max)โ return a random number included betweenminandmax.
โจ Examples
QR-code glow-up time โ commands exactly as the manual gives them:
- 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
Identify and decode a QR code using the libquirc library (see https://github.com/dlbeer/quirc/), and print the identified QR codes positions and payload as metadata. iykyk โจ
To enable the compilation of this filter, you need to configure FFmpeg with --enable-libquirc.
For each found QR code in the input video, some metadata entries are added with the prefix lavfi.quirc.N, where N is the index, starting from 0, associated to the QR code.
A description of each metadata value follows:
lavfi.quirc.countโ the number of found QR codes, it is not set in case none was found.lavfi.quirc.N.corner.M.xandlavfi.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 from0.lavfi.quirc.N.payloadโ the payload of the QR code.
๐ฒ random
Flush video frames from internal cache of frames into a random order. No frame is discarded. Inspired by frei0r nervous filter.
framesโ Set size in number of frames of internal cache, in range from2to512. Default is30.seedโ Set seed for random number generator, must be an integer included between0andUINT32_MAX. If not specified, or if explicitly set to less than0, the filter will try to use a good random seed on a best effort basis.
๐ readeia608
Read closed captioning (EIA-608) information from the top lines of a video frame.
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). A description of each metadata value follows:
lavfi.readeia608.X.ccโ The two bytes stored as EIA-608 data (printed in hexadecimal).lavfi.readeia608.X.lineโ The number of the line on which the EIA-608 data was identified and read.
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].chpโ Enable checking the parity bit. In the event of a parity error, the filter will output0x00for that character. Default is false.lpโ Lowpass lines prior to further processing. Default is enabled.
๐ฎ Commands
This filter supports the all above options as commands.
โจ Examples
- 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
๐ฆ readvitc
Read vertical interval timecode (VITC) information from the top lines of a video frame.
The filter adds frame metadata key lavfi.readvitc.tc_str with the timecode value, if a valid timecode has been detected. Further metadata key lavfi.readvitc.found is set to 0/1 depending on whether timecode data has been found or not.
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-1the full video frame is 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 or less thanthr_w.thr_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 or greater thanthr_b.
โจ Examples
- 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'
๐ remap
Remap pixels using 2nd: Xmap and 3rd: Ymap input video stream.
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 16bit depth, single channel.
formatโ Specify pixel format of output from this filter. Can becolororgray. Default iscolor.fillโ Specify the color of the unmapped pixels. For the syntax of this option, check theColorsection in the ffmpeg-utils manual. Default color isblack.
๐ง removegrain
The removegrain filter is a spatial denoiser for progressive video. sheโs giving cleanup era 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. Description of each mode follows:
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 neighbours 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 neighbours pixels are the closest.14โ Bob mode, interpolates bottom field from the line where the neighbours 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.24โ Similar as23.
๐ removelogo
Suppress a TV station logo, using an image file to determine which pixels comprise the logo. It works by filling in the pixels that comprise the logo with neighboring pixels.
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.
Pixels in the provided bitmap image with a value of zero are not considered part of the logo, 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. For making the filter bitmap, it is recommended to take a screen capture of a black frame with the logo visible, and then using a threshold filter followed by the erode filter once or twice.
Ok so if you need to, you can fix little splotches by hand ๐ โ but bestie, remember: if logo pixels aren't covered, the filter quality gets much worse. Marking too many pixels as part of the logo doesn't hurt as much, but it will increase the amount of blurring needed to cover over the image and will destroy more information than necessary, and those extra pixels will slow things down on a large logo. So likeโฆ be chill about it, ok? ๐ซถ
repeatfields
This filter uses the repeat_field flag from the Video ES headers and hard repeats fields based on its value. Literally just reads the flag and goes "aight, doubling it then" โจ
reverse
Reverse a video clip. It's giving rewind ๐ฌ
Warning: this filter requires memory to buffer the entire clip, so trimming is suggested. Like, your RAM is not infinite babe ๐ญ
Examples
- Take the first 5 seconds of a clip, and reverse it.
trim=end=5,reverse
rgbashift
Shift R/G/B/A pixels horizontally and/or vertically. It's a little pixel shove, ngl ๐ซธ
The filter accepts the following options:
rhโ Set amount to shift red horizontally.rvโ Set amount to shift red vertically.ghโ Set amount to shift green horizontally.gvโ Set amount to shift green vertically.bhโ Set amount to shift blue horizontally.bvโ Set amount to shift blue vertically.ahโ Set amount to shift alpha horizontally.avโ Set amount to shift alpha vertically.edgeโ Set edge mode, can besmear,default, orwarp.
Commands
This filter supports the all above options as commands. Slay ๐
roberts
Apply roberts cross operator to input video stream. Edge detection moment ๐
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 value which will be multiplied with filtered result.deltaโ Set value which will be added to filtered result.
Commands
This filter supports the all above options as commands. โจ
rotate
Rotate video by an arbitrary angle expressed in radians. Spin that thing ๐
The filter accepts the following options:
A description of the optional parameters follows. (Very demure, very mindful of the docs.)
angle,aโ Set an expression for the angle by which to rotate the input video clockwise, expressed as a number of radians. A negative value will result in a counter-clockwise rotation. By default it is set to"0".
This expression is evaluated for each frame. Every single one, bestie ๐ซก
out_w,owโ Set the output width expression, default value is"iw". This expression is evaluated just once during configuration.out_h,ohโ Set the output height expression, default value is"ih". This expression is evaluated just once during configuration.bilinearโ Enable bilinear interpolation if set to1, a value of0disables it. Default value is1.fillcolor,cโ Set the color used to fill the output area not covered by the rotated image. For the general syntax of this option, check the "Color" section in theffmpeg-utilsmanual. If the special value"none"is selected then no background is printed (useful for example if the background is never shown).
Default value is "black". ๐ค
The expressions for the angle and the output size can contain the following constants and functions:
nโ sequential number of the input frame, starting from 0. It is alwaysNANbefore the first frame is filtered.tโ time in seconds of the input frame, it is set to 0 when 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 format"yuv422p"hsubis 2 andvsubis 1.in_w,iw,in_h,ihโ the input video width and height.out_w,ow,out_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 for completely containing the input video rotated byaradians.
These are only available when computing theout_wandout_hexpressions. Not anywhere else, ok? ๐
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 oscillating with a period of T seconds and an amplitude of A radians:
rotate=A*sin(2*PI/T*t)
- Rotate the video, output size is 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, 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 the following commands:
a,angleโ Set the angle 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 vibes with what it had ๐
sab
Apply Shape Adaptive Blur. Soft-focus fairy vibes ๐ง
The filter accepts the following options:
luma_radius,lrโ Set luma blur filter strength, must be a value in range0.1-4.0, default value is1.0. A greater value will result in a more blurred image, and in slower processing.luma_pre_filter_radius,lpfrโ Set luma pre-filter radius, must be a value in the0.1-2.0range, default value is1.0.luma_strength,lsโ Set 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 Set chroma blur filter strength, must be a value in range-0.9-4.0. A greater value will result in a more blurred image, and in slower processing.chroma_pre_filter_radius,cpfrโ Set chroma pre-filter radius, must be a value in the-0.9-2.0range.chroma_strength,csโ Set chroma maximum difference between pixels to still be considered, must be a value in the-0.9-100.0range.
Each chroma option value, if not explicitly specified, is set to the corresponding luma option value. Cute, right? It just copies its sibling ๐
scale
Scale (resize) the input video, using the libswscale library. This is the main-character filter fr fr ๐
The scale filter forces the output display aspect ratio to be the same of the input, 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 will convert the input to the requested format.
Options
The filter accepts the following options, any of the options supported by the libswscale scaler, as well as any of the framesync options.
See the ffmpeg-scaler manual for the complete list of scaler options. (Go read it, iykyk ๐)
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 scale 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. ๐
evalโ Specify when to evaluatewidthandheightexpression. 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.
interlโ Set the interlacing mode. It accepts the following 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 Setlibswscalescaling flags. See theffmpeg-scalermanual for the complete list of values. If not explicitly specified the filter applies the default flags.param0,param1โ Setlibswscaleinput parameters for scaling algorithms that need them. See theffmpeg-scalermanual for the complete documentation. If not explicitly specified the filter applies empty parameters.intentโ Set the ICC rendering intent to use when transforming between different color spaces. It accepts the following 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. ๐relative_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 will reproduce in-gamut colors 1:1 on 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, stretches the input color volume directly onto the output color volume, in non-linear fashion that preserves the original signal appearance as much as possible. This intent is recommended for signal content evaluation, as it will not lead to any clipping. It is 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 Set the video size. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual.in_color_matrix,out_color_matrixโ Set in/output YCbCr color space type.
This setting, bestie, lets you override the autodetected value and also force a specific value used for the output and encoder. If you donโt specify it, the color space type depends on the pixel format.
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_rangeโ set in/output YCbCr sample range. This lets you override the autodetected value and 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 (0-255 in case of 8-bit luma).mpeg/limited/tvโ set "MPEG" range (16-235 in case of 8-bit luma).
in_chroma_loc,out_chroma_locโ set in/output chroma sample location. If not specified, center-sited chroma is used by default. Possible values:auto,unknown,left,center,topleft,top,bottomleft,bottom.in_primaries,out_primariesโ set in/output RGB primaries. This lets you override the autodetected value and force a specific value used for the output and encoder. Possible values:autoโ choose automatically. This is the default.bt709bt470mbt470bgsmpte170msmpte240mfilmbt2020smpte428smpte431smpte432jedec-p22ebu3213
in_transfer,out_transferโ set in/output transfer response curve (TRC). This lets you override the autodetected value and force a specific value used 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_ratioโ enable decreasing or increasing output video width or height if necessary to keep the original aspect ratio. Possible values:disableโ scale the video as specified and disable this feature.decreaseโ output video dimensions will automatically be decreased if needed.increaseโ output video dimensions will automatically be increased if needed.
One useful instance of this option is when you know a specific deviceโs 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 to the command line makes the output 1280x533.
Please note that this is a different thing than specifying -1 for w or h; 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. This works similar to using-nin thewandhoptions.
This option respects the value set for force_original_aspect_ratio, increasing or decreasing the resolution accordingly. The videoโs aspect ratio may be slightly modified.
This option can be handy if you need to have a video fit within or exceed a defined resolution using force_original_aspect_ratio but also have encoder restrictions on width or height divisibility.
reset_sarโ enabling this option leads to the output SAR being reset to1. Additionally, if the user requests proportional scaling either through the width or height expressions, e.g.w=-4:h=360orw=iw/2:h=-1, or by enablingforce_original_aspect_ratio, then the input DAR is taken into account and the output is scaled to produce square pixels. Default isfalse.
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 same asin_wandin_h.out_w,out_hโ the output (scaled) width and height.ow,ohโ same asout_wandout_h.aโ same asiw / ih.sarโ input sample aspect ratio.darโ input display aspect ratio. Calculated from(iw / ih) * sar.hsub,vsubโ horizontal and vertical input chroma subsample values. For example, for the pixel formatyuv422p,hsubis 2 andvsubis 1.ohsub,ovsubโ horizontal and vertical output chroma subsample values. For example, for the pixel formatyuv422p,hsubis 2 andvsubis 1.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.ref_w,rw,ref_h,rh,ref_a,ref_dar,rdar,ref_n,ref_t,ref_posโ equivalent to the above, but for a second reference input. If any of these variables are present, this filter accepts two inputs.
Examples ๐ธ
- 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:
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)
'[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 ๐
This filter supports the following commands:
width,wโ set the output video dimension 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.height,hโ set the output video dimension 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.
scharr ๐
Apply scharr operator to input video stream.
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 value which will be multiplied with filtered result.deltaโ set value which will be added to filtered result.
Commands
This filter supports all of the above options as commands, periodt.
scroll ๐
Scroll input video horizontally and/or vertically by constant speed.
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 ๐
Detect video scene change.
This filter sets frame metadata with mafd between frame, the scene score, and forwards the frame to the next filter, so they can use these metadata to detect scene change or others.
In addition, this filter logs a message and sets frame metadata when it detects a scene change by threshold.
lavfi.scd.mafd metadata keys are set with mafd for every frame.
lavfi.scd.score metadata keys are set with scene change score for every frame to detect scene change.
lavfi.scd.time metadata keys are set with current filtered frame time which detect scene change with 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 for threshold is[0., 100.]. Default value is10..sc_pass,sโ sets the flag to pass scene change frames to the next filter. Default value is0. You can enable it if you want to get a snapshot of scene change frames only. ๐ฌ
๐จ selectivecolor ๐จ
Adjusts cyan, magenta, yellow and black (CMYK) to certain ranges of colors (like "reds", "yellows", "greens", "cyans", ...). The adjustment range is defined by the "purity" of the color โ that is, how saturated it already is. It's basically the Adobe Photoshop Selective Color tool, but make it open source. ๐
The filter accepts the following options:
correction_methodโ selects the color correction method. Available values are:absoluteโ the specified adjustments are applied "as-is" (added/subtracted to the original pixel component value).relativeโ the 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 than 128)neutralsโ adjustments for all pixels except pure black and pure whiteblacksโ adjustments for black pixels (pixels where all components are lesser than 128)psfileโ specify a Photoshop selective color file (.asv) to import the settings from. ๐
All the adjustment settings (reds, yellows, ...) 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.
๐ธ Examples ๐ธ
- Increase cyan by 50% and reduce yellow by 33% in every green area, 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
๐ฆ separatefields ๐ฆ
The separatefields filter takes a frame-based video input and splits each frame into its component fields, producing a new half height clip with twice the frame rate and twice the frame count. Literally doubling everything, main character energy. โจ
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.
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, e.g. in case of scaling or if another setdar or a setsar filter is applied. So yeah, it's giving "teamwork makes the dream work" โ later filters can absolutely undo your vibe. 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.
It accepts the following parameters:
r,ratio,dar("setdar" only),sar("setsar" only) 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 formatyuv422phsub is 2 and vsub is 1.
โญ Examples โญ
- 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
๐ setfield ๐
Forces the field for the output video frame.
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, which affects how the frame is treated by following filters (e.g. fieldorder or yadif). Sneaky little metadata queen. ๐
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.
๐ setparams ๐
Forces frame parameters 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 setfield โ all vibes, no pixels touched. โจ
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 mode. Available values are:autoโ keep the same alpha mode (default).unspecified,unknownpremultipliedstraight
๐ซ shear ๐ซ
Applies shear transform to the input video. It's slanted, it's cute, it's a whole look. ๐ฆ
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 the ffmpeg-utils manual. 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 all the above options as commands. ๐
๐ showinfo ๐
Shows a line containing various information for each input video frame. The input video is not modified. Purely a "let me just look at you" filter. ๐
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 from 0.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, bestie. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual.iโ the type of interlaced mode:"P"for progressive,"T"for top field first,"B"for bottom field first.iskeyโ this is1if the frame is a key frame,0otherwise.typeโ 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 refer to the documentation of theAVPictureTypeenum and of theav_get_picture_type_charfunction defined inlibavutil/avutil.h. iykyk ๐checksumโ the Adler-32 checksum (printed in hexadecimal) of all the planes of the input frame.plane_checksumโ the Adler-32 checksum (printed in hexadecimal) of each plane of the input frame, expressed in the form[c0 c1 c2 c3].meanโ the mean value of pixels in each plane of the input frame, expressed in the form[mean0 mean1 mean2 mean3].stdevโ the standard deviation of pixel values in each plane of the input frame, expressed in the form[stdev0 stdev1 stdev2 stdev3].
showpalette ๐จ
Displays the 256 colors palette of each frame. Ngl this filter is only relevant for pal8 pixel format frames โ like, don't come for it if your frames aren't pal8, it literally can't help you.
It accepts the following option:
sโ Set the size of the box used to represent one palette color entry. Default is30(for a30x30pixel box).
shuffleframes ๐
Reorder and/or duplicate and/or drop video frames. Yes, all three, it's giving multitasking queen.
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. Number of indexes also sets 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.
Examples
- 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
shufflepixels ๐ฆ
Reorder pixels in video frames. Tiny pixels, big chaos.
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 be horizontal, vertical or block mode.width,wandheight,hโ Set shuffleblock_size. In case of horizontal shuffle mode only the width part of size is used, and in case of vertical shuffle mode only the height part of size is used.seed,sโ Set random seed used with shuffling pixels. Mainly useful to set to be able to reverse filtering process to get original input. For example, to reverse forward shuffle you need to use same parameters and exact same seed and to set direction to inverse. Write that seed down babes, it's your only way back. ๐ซถ
shuffleplanes ๐
Reorder and/or duplicate video planes. Plane-on-plane crime, but make it aesthetic.
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.
Examples
- Swap the second and third planes of the input:
ffmpeg -i INPUT -vf shuffleplanes=0:2:1:3 OUTPUT
signalstats ๐
Evaluate various visual metrics that assist in determining issues associated with the digitization of analog video media. It's like a vibe check for your analog capture, fr fr.
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:
statandoutโstatandoutspecify an additional form of image analysis.outoutputs video with the specified type of pixel highlighted. ๐
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 is yellow. ๐
Examples
- 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}
signature ๐๏ธ
Calculates the MPEG-7 Video Signature. The filter can handle more than one input. In this case 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. It's literally fingerprinting your video, main character forensics energy.
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. โก
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. ๐ซถ Heads up though: if you've got more than one input, this path has to be a prototype โ meaning it must contain%dor%0nd(where n is a positive integer) and that bit gets swapped out for the input number. And if you don't specify a filename at all? Nothing gets written. That's the default, bestie. ๐formatโ picks the output format. Your options are:binaryโ uses the specified binary representation (this is the default, no cap).xmlโ uses the specified xml representation. โจ
th_dโ sets the threshold for detecting one word as similar. The value has to be an integer greater than zero. Default is9000. ๐th_dcโ sets the threshold for detecting all words as similar. Again, integer greater than zero required. Default is60000.th_xhโ sets the threshold for detecting frames as similar. Integer greater than zero, please and thank you. Default is116.th_diโ sets the minimum length of a sequence, in frames, to recognize it as a matching sequence. Value must be a non negative integer. Default is0.th_itโ sets the minimum relation that matching frames to all frames must have. Value must be a double between0and1. Default is0.5. ๐ฆ
โจ Examples โจ
- Wanna calculate the signature of an input video and stash it in
signature.bin? Say less:
ffmpeg -i input.mkv -vf signature=filename=signature.bin -map 0:v -f null -
- Wanna detect whether two videos match and store the signatures in XML format in
signature0.xmlandsignature1.xml? Iconic, do this:
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 -
๐ธ siti ๐ธ
Calculates Spatial Information (SI) and Temporal Information (TI) scores for a video, exactly 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. ๐
Ngl bestie, heads up: this is a legacy implementation that corresponds to a superseded recommendation. For 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 literally one option:
print_summaryโ if set to1, summary statistics get printed to the console. Default0.
โจ Examples โจ
- To calculate SI/TI metrics and print summary:
ffmpeg -i input.mp4 -vf siti=print_summary=1 -f null -
๐ฆ smartblur ๐ฆ
Blurs the input video without touching the outlines. It's giving soft-focus main character energy. ๐
It accepts the following options:
luma_radius,lrโ sets the luma radius. The value must be a float in the range[0.1,5.0]specifying the variance of the gaussian filter used to blur the image (bigger = slower, sorry ๐ญ). Default is1.0.luma_strength,lsโ sets the luma strength. Must be a float in the range[-1.0,1.0]and it configures the blurring: a value in[0.0,1.0]blurs the image, while a value in[-1.0,0.0]sharpens it. Default1.0.luma_threshold,ltโ sets the luma threshold, used as a coefficient to decide whether a pixel should be blurred or not. Must be an integer in the range[-30,30]. A value of0filters all the image, a value in[0,30]filters flat areas, and a value in[-30,0]filters edges. Default0.chroma_radius,crโ sets the chroma radius. Float in[0.1,5.0], same deal: variance of the gaussian filter used to blur (slower if larger). Default isluma_radius.chroma_strength,csโ sets the chroma strength. Float in[-1.0,1.0];[0.0,1.0]blurs,[-1.0,0.0]sharpens. Default isluma_strength.chroma_threshold,ctโ sets the chroma threshold, same coefficient situation as luma. Integer in[-30,30];0filters everything,[0,30]filters flat areas,[-30,0]filters edges. Default isluma_threshold.alpha_radius,arโ sets the alpha radius. Float in[0.1,5.0], variance of the gaussian filter (slower if larger). Default isluma_radius.alpha_strength,asโ sets the alpha strength. Float in[-1.0,1.0];[0.0,1.0]blurs,[-1.0,0.0]sharpens. Default isluma_strength.alpha_threshold,atโ sets the alpha threshold, coefficient-style. Integer in[-30,30];0filters everything,[0,30]flat areas,[-30,0]edges. Default isluma_threshold.
Fr fr: if a chroma or alpha option isn't explicitly set, the corresponding luma value gets used instead. ๐ซถ
๐ sobel ๐
Applies the sobel operator to the input video stream. Edge detection slay. ๐ฅ
The filter accepts the following option:
planesโ sets which planes will be processed; unprocessed planes get copied. Default value is0xf, which means 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.
Commands
This filter supports the all above options as commands. ๐
๐ spp ๐
Applies a simple postprocessing filter that compresses and decompresses the image at several shifts โ or, in the case of quality level 6, all shifts โ and averages the results.
The filter accepts the following options:
qualityโ sets quality. This option defines the number of levels for averaging, and it accepts an integer in the range0-6. If set to0, the filter has no effect at all. A value of6means higher quality. For each increment of that value the speed drops by a factor of approximately 2. Default value is3. ๐ญqpโ 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 are: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. Using this option may cause flicker, since the B-Frames have often larger QP. Default is0(not enabled).
Commands
This filter supports the following commands:
quality,levelโ sets the quality level. The value"max"can be used to set the maximum level, currently6. โจ
๐ง sr ๐ง
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. The original repository is at https://github.com/HighVoltageRocknRoll/sr.git. ๐ซถ
The filter accepts the following options:
dnn_backendโ specifies 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 sets the path to the model file specifying network architecture and its parameters. Note that different backends use different file formats. TensorFlow and OpenVINO backends can load files for only its format.scale_factorโ sets the scale factor for the SRCNN model. Allowed values are2,3and4. Default value is2. Scale factor is necessary for the SRCNN model, because it accepts input upscaled using bicubic upscaling with proper scale factor.
Lowkey important: to get full functionality (such as async execution), please use the dnn_processing filter. ๐
๐ sr_amf ๐
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.
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 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.
โจ Examples โจ
- 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
โญ ssim โญ
Obtains the SSIM (Structural SImilarity Metric) between two input videos. ๐ฆ
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.
both video inputs have to match on resolution and pixel format or this filter just won't work right โ that's the vibe check it needs to pass ๐ค. It also lowkey assumes both inputs have the same number of frames, and it compares them one by one, bestie, one by one.
The filter stores the calculated SSIM of each frame ๐พ.
The description of the accepted parameters follows, and yes we're doing all of them:
stats_file,fโ if you specify this, the filter uses the named file to save the SSIM of each individual frame ๐. And when the filename equals-, the data gets sent to standard output, iconic behaviour honestly.
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 ๐ซถ.
A description of each shown parameter follows:
nโ sequential number of the input frame, starting from1๐ขY,U,V,R,G,Bโ SSIM of the compared frames for the component specified by the suffix ๐Allโ SSIM of the compared frames for the whole frame ๐dBโ same as above but in dB representation ๐
This filter also supports the framesync options, iykyk โจ
Examples
- for example, this whole situation right here:
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 ๐ฌ. The SSIM of each individual frame is stored in stats.log, no cap.
- another example with both
psnrandssimat same time, because we multitask ๐ :
ffmpeg -i main.mpg -i ref.mpg -lavfi "ssim;[0:v][1:v]psnr" -f null -
- and another example with different containers ๐ฑ:
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 -
stereo3d ๐
Convert between different stereoscopic image formats ๐ฅฝ.
The filters accept the following options (yes, "filters", that's what it says, plural energy):
inโ set the stereoscopic image format of input ๐ฅ
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. ๐
outโ set the stereoscopic image format of output ๐คsbslโ 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 ๐ฅ๏ธ
Default value is arcd. ๐ฆ
Examples
- convert input video from side by side parallel to anaglyph yellow/blue dubois, slay:
stereo3d=sbsl:aybd
- convert input video from above below (left eye above, right eye below) to side by side crosseye:
stereo3d=abl:sbsr
streamselect, astreamselect ๐๏ธ
Select video or audio streams ๐.
The filter accepts the following options:
inputsโ set number of inputs. Default is2โ๏ธmapโ set input indexes to remap to outputs ๐บ๏ธ
Commands
The streamselect and astreamselect filter supports the following commands:
mapโ set input indexes to remap to outputs
Examples
- select first 5 seconds 1st stream and rest of time 2nd stream, chef's kiss:
sendcmd='5.0 streamselect map 1',streamselect=inputs=2:map=0
- same as above, but for audio ๐ง:
asendcmd='5.0 astreamselect map 1',astreamselect=inputs=2:map=0
subtitles ๐ฌ
Draw subtitles on top of input video using the libass library โ๏ธ.
To enable compilation of this filter you need to configure FFmpeg with --enable-libass โ ๏ธ. This filter also requires a build with libavcodec and libavformat to convert the passed subtitles file to ASS (Advanced Substation Alpha) subtitles format, that's the โจ pipeline โจ.
The filter accepts the following options:
filename,fโ set the filename of the subtitle file to read ๐. It must be specified, no skipping.original_sizeโ specify the size of the original video, the video for which the ASS file was composed ๐๏ธ. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Due to a misdesign in ASS aspect ratio arithmetic (not our fault, bestie ๐ญ), 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 ๐ค. These fonts will be used in addition to whatever the font provider uses.alphaโ process alpha channel, by default alpha channel is untouched ๐ซฅcharencโ set subtitles input character encoding.subtitlesfilter only. Only useful if not UTF-8 ๐ฃstream_index,siโ set subtitles stream index.subtitlesfilter only ๐ขforce_styleโ override default style or script info parameters of the subtitles ๐ . It accepts a string containing ASS style formatKEY=VALUEcouples separated by,.wrap_unicodeโ break lines according to the Unicode Line Breaking Algorithm ๐. 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. ๐ธ
If the first key is not specified, it is assumed that the first value specifies the filename ๐ค.
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 โ yes this is as cute as it sounds ๐:
subtitles=sub.srt:force_style='Fontname=DejaVu Serif,PrimaryColour=&HCCFF0000'
super2xsai ๐น๏ธ
Scale the input by 2x and smooth using the Super2xSaI (Scale and Interpolate) pixel art scaling algorithm ๐จ.
Useful for enlarging pixel art images without reducing sharpness โ the retro gamer's bestie fr fr ๐พ.
swaprect ๐
Swap two rectangular objects in video, because sometimes you just gotta move the rectangle ๐ฆ.
This filter accepts the following options:
wโ set object widthhโ set object heightx1โ set 1st rect x coordinatey1โ set 1st rect y coordinatex2โ set 2nd rect x coordinatey2โ set 2nd rect y coordinate
All expressions are evaluated once for each frame โฑ๏ธ.
The all options are expressions containing the following constants, and yes, they're giving math class but make it fun:
w,hโ the input width and height ๐aโ same asw / hsarโ input sample aspect ratiodarโ input display aspect ratio, it is the same as(w / h) * sarnโ the number of the input frame, starting from0๐ขtโ the timestamp expressed in seconds. It'sNANif the input timestamp is unknown ๐คทโโ๏ธposโ the position in the file of the input frame,NANif unknown; deprecated, do not use ๐
Commands
This filter supports the all above options as commands ๐ฎ.
swapuv
Swaps the U and V planes. That's it. That's the whole filter. ๐
tblend
Blends successive video frames together โ one on top of the other, chef's kiss. โจ
See blend (like, go read that one, it's the whole story).
telecine
Applies the telecine process to your video. Yes, the pulldown thing. Vintage cinema vibes, no cap. ๐
It takes these options:
first_fieldโ which field gets to go first. Values:top,tโ top field firstbottom,bโ bottom field first- The default value is
"top".
patternโ a string of numbers representing the pulldown pattern you wish to apply. The default value is23.
Some typical patterns, bestie โ screenshot this:
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. Like the histogram filter but with main character energy over time. ๐
Unlike histogram, which only shows the histogram of a single input frame at a certain time, this filter also shows past histograms, for the number of frames defined by the width option.
The computed histogram is a representation of the color component distribution in an image.
Options, let's go:
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].display_mode,dโ sets the display mode. Accepts: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 inparade, 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".slideโ sets the slide mode. Available values are: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
"replace".
threshold
Applies the threshold effect to your video stream. ๐ฆ
This filter needs four video streams to do its thresholding thing. First stream is the stream we're filtering. Second stream holds the threshold values, third stream holds the min values, and last โ fourth โ stream holds the max values.
It takes this option:
planesโ sets which planes will be processed; unprocessed planes will be copied. By default the value is0xf, meaning all planes will be processed.
So like, for example: if a pixel's component value in the first stream is less than the threshold value of that pixel component from the 2nd (threshold) stream, the third stream value gets picked โ otherwise the fourth stream's pixel component value gets picked. Sorting hat behaviour, honestly. ๐
Using the color source filter, you can perform various types of thresholding:
Commands
This filter supports all the options as commands.
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. The it-girl of every batch, lowkey. ๐
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".
Okay so heads up: 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. Don't say I didn't warn you ๐
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. Grid moment โจ
The untile filter can do the reverse. Reversible queen.
Options:
layoutโ sets the grid size in the formCOLUMNSxROWS. Range is 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 (such as 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 theColorsection 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 get that 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 0 is necessary to prevent ffmpeg from duplicating each output frame to accommodate the originally detected frame rate. Like, actually necessary. ๐ซถ
- 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 the tilt-and-shift effect. ๐
What happens when you invert time and space? Buckle up.
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, since there are no infinite-width frames, 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 is either very little motion and the background is static, or when there is a lot of motion and a very wide depth of field (e.g. wide panorama, while moving on a train). Train window aesthetic, literally iconic. ๐
It accepts these parameters:
tiltโ tilt video while shifting (default). When unset, 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 into its place. Similarly, the last video frame may be reconstructed at the end. Alternatively it is 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. Old-school but make it โจaestheticโจ.
Frames are counted starting from 1, so the first input frame is considered odd. (Not me counting from one ๐)
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
Output:
11111 33333
22222 44444
11111 33333
22222 44444
11111 33333
22222 44444
11111 33333
22222 44444
drop_even,1โ bestie, we're only letting the odd frames through, the even ones get yeeted. Result: same height, half the frame rate โจ
------> 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,2โ the flip side, fr. Only even frames survive, odds are gone, height stays the same, half frame rate 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:
22222 44444
22222 44444
22222 44444
22222 44444
pad,3โ every frame gets stretched to full height, but the in-between lines get padded with black. Double height, same input frame rate, very much a vibe ๐
------> 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,4โ taking the upper field from odd frames and the lower field from even frames, weaving them together like a friendship bracelet ๐ 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:
11111 33333
22222 44444
11111 33333
22222 44444
interleave_bottom,5โ same energy but flipped: lower field from odd frames, upper field from even frames ๐ฆ 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
interlacex2,6โ double the frame rate, height unchanged. New frames get inserted, each one carrying the second temporal field from the previous input frame plus the first temporal field from the next input frame. Heads up: this mode relies on thetop_field_firstflag. It's the move for interlaced video displays with no field synchronisation ๐ฅ
------> 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
mergex2,7โ odd frames go into the upper field, even frames go into the lower field, and you get double height at the same frame rate. Chef's kiss ๐ธ
------> 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
Numeric values are deprecated but hey, they're still accepted for backward compatibility reasons ๐
Default mode is "merge", iykyk.
๐ flags
Specify flags influencing the filter process, bestie. That's literally it.
Available value for flags is:
low_pass_filter,vlpfโ turns on linear vertical low-pass filtering in the filter. Ngl you need vertical low-pass filtering 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 โจcomplex_filter,cvlpfโ turns on complex vertical low-pass filtering. This reduces interlace 'twitter' and Moire patterning slightly less, but it better retains detail and the subjective sharpness impression ๐bypass_ilโ skips over frames that are already interlaced, and only adjusts the frame rate.
Real talk: vertical low-pass filtering and bypassing already interlaced frames can only be enabled for modeinterleave_topandinterleave_bottom. No cap.
๐ tmedian
Picks the median pixels from several successive input video frames. Iconic behaviour, honestly.
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, by which all planes are processed ๐ซถpercentileโ sets the median percentile. Default value is0.5. A default of0.5will always pick median values, while0picks minimum values and1picks maximum values. Sliding that slider, love that for us.
Commands
This filter supports all the above options as commands โ excluding option "radius" ๐
๐ฆ tmidequalizer
Applies the Temporal Midway Video Equalization effect โจ
Midway Video Equalization adjusts a sequence of video frames so they all have the same histograms, while keeping their dynamics as much as possible. It's useful for, like, matching exposures from a sequence of video frames. Genuinely obsessed.
This filter accepts the following option:
radiusโ sets the filtering radius. Default is5. Allowed range is from1to127.sigmaโ sets the filtering sigma. Default is0.5. This controls the strength of the filtering. Setting this option to0effectively does nothing, which, okay, sure ๐ฅฒplanesโ sets which planes to process. Default is15, which is all available planes ๐
โญ tmix
Mixes successive video frames together. Group project energy but it actually works.
A description of the accepted options follows.
framesโ the number of successive frames to mix. If unspecified, it defaults to3.weightsโ specify the weight of each input video frame. Each weight is separated by a space. If the number of weights is smaller than the number of frames, the last specified weight gets reused for all the remaining unset weights ๐ฏscaleโ specify scale. If it's set, it gets multiplied with the sum of each weight multiplied with pixel values, giving you the final destination pixel value. By default,scaleis auto-scaled to the sum of the 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 a simple temporal convolution:
tmix=frames=3:weights="-1 3 -1"
- Similar to the 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
tonemap ๐
Tone map colors from different dynamic ranges. HDR bestie meets SDR bestie and they get along ๐
This filter expects data in single precision floating point, because it genuinely needs to operate on (and can output!) out-of-range values. So yeah, you'll need another filter like zscale to convert the resulting frame back to a format that's actually usable.
Heads up! The tonemapping algorithms implemented here only work on linear light, so the input data should be linearized beforehand (and possibly correctly tagged). No skipping that step, bestie ๐ญ
ffmpeg -i INPUT -vf zscale=transfer=linear,tonemap=clip,zscale=transfer=bt709,format=yuv420p OUTPUT
Options โจ
The filter accepts the following options.
tonemapโ set the tone map algorithm to use, bestie. 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 ๐๏ธ
This affects the following algorithms:
noneโ ignored. (yeah, it does nothing here, we been knew)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 ๐ธ 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. No tag, no desat, periodt.
peakโ override signal/nominal/reference peak with this value. Useful when the embedded peak information in display metadata is not reliable ๐ or when tone mapping from a lower range to a higher range.
tpad ๐
Temporarily pad video frames. Like a little cushion for your stream, cute right?
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 ๐ณ 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 ofcoloris"black".
transpose ๐ฆ
Transpose rows with columns in the input video and optionally flip it. It's giving gymnastics, honestly.
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 between4-7, the transposition is only done if the input video geometry is portrait and not landscape. These values are deprecated, thepassthroughoption should be used instead. And numerical values are deprecated too, and should be dropped in favor of symbolic constants. We're moving on, bestie 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
trim โ๏ธ
Trim the input so that the output contains one continuous subpart of the input. We're cropping the timeline, not the pixels, iykyk.
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.
Ngl this next bit matters a lot: 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. Bestie please don't forget thesetpts๐
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.
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. Slay, flexible queen ๐
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
unpremultiply ๐
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. No mixing and matching, bestie ๐ซถ
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. Bit math era fr fr ๐งฎ
inplaceโ do not require 2nd input for processing, instead use alpha plane from input stream.
unsharp โญ
Sharpen or blur the input video. Pick a lane, honestly, and the filter will do whichever you set.
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, positive values sharpen it, and a value of 0 disables the effect entirely. Default value is 0.0. Slay.
alpha_msize_x,axโ sets the alpha matrix horizontal size. Gotta be an odd integer between 3 and 23. Default?5. โจalpha_msize_y,ayโ sets the alpha matrix vertical size. Also an odd integer between 3 and 23, bestie. Default is5.alpha_amount,aaโ sets the alpha effect strength. Floating point number, and the reasonable zone is between-1.5and1.5.
Negative values blur the input video, positive ones sharpen it, and 0 disables the effect. Default value is 0.0.
All parameters are optional and default to the equivalent of the string '5:5:1.0:5:5:0.0'. Like, every single one. ๐ซถ
Examples
- Apply strong luma sharpen effect:
unsharp=luma_msize_x=7:luma_msize_y=7:luma_amount=2.5
- Apply a strong blur of both luma and chroma parameters:
unsharp=7:7:-2:7:7:-2
untile
Decomposes a video made of tiled images back into the individual images. It's giving reverse-engineering energy and I'm obsessed. ๐ฆ
The frame rate of the output video is the frame rate of the input video multiplied by the number of tiles. Math! We love her.
This filter does the 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, check the "Video size" section in theffmpeg-utilsmanual. iykyk.
Examples
- Produce a 1-second video from a still image file made of 25 frames stacked vertically, like an analogic film reel:
ffmpeg -r 1 -i image.jpg -vf untile=1x25 movie.mkv
uspp
Applies an ultra slow/simple postprocessing filter that compresses and decompresses the image at several (or โ in the case of quality level 8 โ all) shifts and averages the results. She's thorough, she's slow, she's iconic. ๐
The way this differs from the behavior 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. No cap.
Heads up bestie: this filter is not available in ffmpeg versions between 5.0 and 6.0. Check your version before you come for her. 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 set to0, the filter will have no effect. A value of8means the higher quality. For each increment of that value the speed drops by a factor of approximately2. Default value is3. (So yes, quality 8 is a commitment. ๐)qpโ force a constant quantization parameter. If not set, the filter will use the QP from the video stream (if available).codecโ use specified codec instead ofsnow.
v360
Convert 360 videos between various formats. Literally a whole world of projections, buckle up. ๐๐
The filter accepts the following options:
inputoutputโ set format of the input/output video.
Available formats:
e,equirectโ Equirectangular projection.c3x2,c6x1,c1x6โ Cubemap with3x2/6x1/1x6layout.
Format specific options:
in_pad,out_padโ set padding proportion for the input/output cubemap. Values in decimals.
Example values:
0โ No padding.0.01โ 1% of face is padding. For example, with 1920x1280 resolution face size would be640x640and padding would be3pixels from each side. (640 * 0.01 = 6pixels)
Default value is 0. Maximum value is 0.1.
fin_pad,fout_padโ set fixed padding for the input/output cubemap. Values in pixels.
Default value is 0. If greater than zero it overrides other padding options. (She said what she said. ๐)
in_forder,out_forderโ set 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.
in_frot,out_frotโ set 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.
Format specific options:
h_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view. (Diagonal is the main character, apparently. โจ)
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
dfisheyeโ Dual fisheye.
Format specific options:
h_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
barrel,fb,barrelsplitโ Facebook's 360 formats. (Mark Zuckerberg could never, honestly.)sgโ Stereographic format.
Format specific options:
h_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
mercatorโ Mercator format.ballโ Ball format, gives significant distortion toward the back. She's quirky like that. ๐hammerโ Hammer-Aitoff map projection format.sinusoidalโ Sinusoidal map projection format.fisheyeโ Fisheye projection.
Format specific options:
h_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
panniniโ Pannini projection.
Format specific options:
h_fovโ set output pannini parameter.ih_fovโ set input pannini parameter.
cylindricalโ Cylindrical projection.
Format specific options:
h_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
perspectiveโ Perspective projection. (output only, okurrr)
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_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ogโ Orthographic format.
Format specific options:
h_fov,v_fov,d_fovโ set output horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
ih_fov,iv_fov,id_fovโ set input horizontal/vertical/diagonal field of view. Values in degrees.
If diagonal field of view is set it overrides horizontal and vertical field of view.
octahedronโ Octahedron projection.cylindricaleaโ Cylindrical Equal Area projection.interpโ set interpolation method. Note: more complex interpolation methods require much more memory to run. (Your RAM is gonna feel it, fr fr. 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.
Default value is line. โ
w,hโ sets the output video resolution. Lowkey the default resolution depends on formats, so don't come at it expecting a fixed number ๐ซin_stereo,out_stereoโ sets the input/output stereo format, bestie:2dโ 2D monosbsโ side by sidetbโ top bottom- Default value is
2dfor input and output format. That's the vibe out of the box ๐
yaw,pitch,rollโ sets rotation for the output video. Values in degrees, periodt.rorderโ sets the rotation order for the output video. Pick one item for each position:y,Yโ yawp,Pโ pitchr,Rโ roll- Default value is
ypr. Iconic little triple ๐ธ
h_flip,v_flip,d_flipโ flips the output video horizontally (swaps left-right)/vertically (swaps up-down)/in-depth (swaps back-forward). Boolean values, no cap.ih_flip,iv_flipโ sets whether the input video is flipped horizontally/vertically. Boolean values ๐ฆin_transโ sets whether the input video is transposed. Boolean value, and by default it's disabled.out_transโ sets whether the output video needs to be transposed. Boolean value, by default disabled.h_offset,v_offsetโ sets the output horizontal/vertical off-axis offset. Default is set to0. Allowed range is from-1to1. Stay in your lane or it won't work ๐alpha_maskโ builds a mask in the alpha plane for all unmapped pixels by marking them fully transparent. Boolean value, by default disabled.reset_rotโ resets the rotation of the output video. Boolean value, by default disabled. Main character energy: start fresh โจ
Examples ๐ฌ
- 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
This filter supports subset of above options as commands. So yes, you can yeet these at it live ๐ซถ
vaguedenoiser
Applies a wavelet based denoiser. It's giving "glow-up for grainy footage" โจ
So here's the whole situation: it transforms each frame from the video input into the wavelet domain, using Cohen-Daubechies-Feauveau 9/7 (yes, that's the whole name, I didn't make it up ๐). Then it applies some filtering to the obtained coefficients. It does an inverse wavelet transform after. And because wavelet properties are Like That, it should give you a nice smoothed result, and reduced noise, without blurring picture features. Obsessed honestly.
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 starts looking 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 an intermediary situation between (more) soft and (less) hard thresholding.- Default is
garrote. She's the middle child and she ate ๐
nstepsโ number of times the wavelet will decompose the picture. Picture can't be decomposed beyond a particular point (typically,8for 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
Applies a variable blur filter by using a 2nd video stream to set the blur radius. Heads up: the 2nd stream must have the same dimensions, no exceptions, it's giving strict bestie behavior ๐ค
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. ๐ง
Commands
This filter supports all the above options as commands. Every single one, slay ๐
vectorscope
Displays 2 color component values in the two dimensional graph (which is called a vectorscope). It's the aesthetic plot moment of the whole page ๐
This filter accepts the following options:
mode,mโ set vectorscope mode. It accepts the following values:gray,tintโ gray values are displayed on graph, higher brightness means more pixels have 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,eโnoneโ no envelope, this is default.instantโ instant envelope, even the darkest single pixel will be clearly highlighted. Not one pixel left behind ๐peakโ 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. Both. At once. Periodt.
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. Math is mathing ๐งฎhthreshold,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,t0andtint1,t1โ set color tint for gray/tint vectorscope mode. By default both options are zero. This means no tint, and output will remain gray. Respect the neutral era ๐ฉถ
vidstabdetect
Analyzes video stabilization/deshaking. It performs pass 1 of 2 โ see vidstabtransform for pass 2, because this filter is the setup girlie and that one is the payoff ๐
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. No flag, no filter โ that's the whole deal ๐จ
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. She's thorough ๐ฅstepsizeโ 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 to0, it is disabled. The frames are counted starting from1. (Yes, from1, not0โ don't come for me ๐ญ)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). Efficiency queen ๐
Examples ๐ฌ
- 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:
...and the code block from that last example wraps up with just this one lonely line:
vidstabdetect=show=1
- Want to analyze a video with medium shakiness using
ffmpeg? Say less:
ffmpeg -i input -vf vidstabdetect=shakiness=5:show=1 dummy.avi
๐ vidstabtransform ๐
Video stabilization/deshaking: this is pass 2 of 2, bestie โ if you skipped pass 1, go look at vidstabdetect first, iykyk.
So what it does: it reads a file that has transform information for each frame, then applies/compensates those transforms. Team it up with vidstabdetect and boom, you've got yourself a deshaker. See also <http://public.hronopik.de/vid.stab>. And important: you also gotta use the unsharp filter, see below, fr fr.
To enable compilation of this filter you need to configure FFmpeg with --enable-libvidstab. No flag, no filter. ๐
Options
inputโ Set the path to the file it reads the transforms from. Default value istransforms.trf.smoothingโ Set the number of frames (value*2 + 1) used for lowpass filtering the camera movements. Default value is10. For example, a number of10means that 21 frames are used (10 in the past and 10 in the future) to smoothen the motion in the video. A larger value leads to a smoother video, but it limits the acceleration of the camera (pan/tilt movements).0is a special case where a static camera is simulated.optalgoโ Set the camera path optimization algorithm. Accepted values are:gaussโ gaussian kernel low-pass filter on camera motion (default)avgโ averaging on transformations
maxshiftโ Set the maximal number of pixels to translate frames. Default value is-1, meaning no limit.maxangleโ Set the maximal angle in radians (degree*PI/180) to rotate frames. Default value is-1, meaning no limit.cropโ Specify 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 Set percentage to zoom. A positive value will result in a zoom-in effect, a negative value in a zoom-out effect. Default value is0(no zoom).optzoomโ Set 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), seezoomspeedNote that the value given atzoomis added to the one calculated here.
zoomspeedโ Set percent to zoom maximally each frame (enabled whenoptzoomis set to2). Range is from0to5, default value is0.25.interpolโ Specify 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. Use alsotripodoption ofvidstabdetect.debugโ Increase log verbosity if set to1. Also the detected global motions are 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. ๐
- 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
๐ vflip ๐
Flip the input video vertically. That's it, that's the filter. โจ
For example, to vertically flip a video with ffmpeg:
ffmpeg -i in.avi -vf "vflip" out.avi
๐ vfrdet ๐
Detect variable frame rate video. 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 the ones with constant delta pts. If there were frames with variable delta, then it will also show min, max and average delta encountered. Receipts on receipts. ๐งพ
๐ vibrance ๐
Boost or alter saturation. The filter accepts the following options:
intensityโ Set strength of boost if positive value, or strength of alter if negative value. Default is0. Allowed range is from-2to2.rbalโ Set the red balance. Default is1. Allowed range is from-10to10.gbalโ Set the green balance. Default is1. Allowed range is from-10to10.bbalโ Set the blue balance. Default is1. Allowed range is from-10to10.rlumโ Set the red luma coefficient.glumโ Set the green luma coefficient.blumโ Set 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 the above options as commands. ๐ซถ
๐๏ธ vif ๐๏ธ
Obtain the average VIF (Visual Information Fidelity) between two input videos.
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.
The obtained average VIF score is 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 -
๐ vignette ๐
Make or reverse a natural vignetting effect. Aesthetic. The filter accepts the following options:
angle,aโ Set lens angle expression as a number of radians. The value is clipped in the[0,PI/2]range. Default value:PI/5x0,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 isforward.
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 isinit.
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 is1/1.
Expressions
The alpha, x0 and y0 expressions can contain the following parameters.
w,hโ input width and heightnโ the number of input frame, starting from 0ptsโ 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
๐ฅ vmafmotion ๐ฅ
Obtain the average VMAF motion score of a video. It is one of the component metrics of VMAF.
The obtained average motion score is 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 -
โก vpp_amf โก
Scale (resize) and convert colorspace, transfer characteristics or color primaries for the input video, using AMD Advanced Media Framework library for hardware acceleration. Setting the output width and height works in the same way as for the scale filter. ๐ฅ
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 thescalefilter.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 LinearlogโLOGlog-sqrtโLOG_SQRTiec61966-2-4โiec61966-2-4bt1361-ecgโBT1361_ECGiec61966-2-1โiec61966-2-1bt2020-10โ BT.2020 for 10-bits contentbt2020-12โ BT.2020 for 12-bits content
smpte2084โ SMPTE2084 ๐smpte428โ SMPTE428arib-std-b67โ ARIB_STD_B67primariesโ picks the output color primaries, bestie. The accepted values (and what they actually are) are: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
Examples โจ
- Scale input to 720p, keeping aspect ratio and ensuring the output is
yuv420p. Iconic little one-liner:
vpp_amf=-2:720:format=yuv420p
- Upscale to 4K and change color profile to
bt2020. Glow-up time ๐ฆ:
vpp_amf=4096:2160:color_profile=bt2020
๐ธ vstack ๐ธ
Stacks input videos vertically, like, literally one on top of the other.
Every stream has to have the same pixel format and the same width, no cap.
Fun fact: this filter is faster than doing the same output with overlay and pad, so use it, bestie, it's giving efficiency ๐
The filter accepts the following options:
inputsโ sets the number of input streams. Default is2.shortestโ if set to1, the output is forced to terminate when the shortest input terminates. Default value is0.
๐ซถ w3fdif ๐ซถ
Deinterlaces the input video (w3fdif stands for "Weston 3 Field Deinterlacing Filter" โ yes, that's a whole mouthful).
It's 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. BBC really said "we'll handle the fields" ๐
This filter uses field-dominance info in the frame to decide which of each pair of fields goes first in the output. If it gets it wrong, use the setfield filter before the w3fdif filter โ that's the fix, iykyk.
There are two sets of filter coefficients, the so-called "simple" and "complex". Which set gets used can be set by passing an optional parameter:
filterโ sets the interlacing filter coefficients. Accepts one of: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: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: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 specifies which frames to deinterlace. Accepts one of:allโ deinterlace all frames,interlacedโ only deinterlace frames marked as interlaced.
Default value is all.
Commands ๐
This filter supports the same commands as options. Slay.
๐ waveform ๐
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's giving "data but make it art" โจ
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 sets 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 sets 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 sets 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 displays a separate graph for the color components side by side in"row"mode or one below the other in"column"mode.paradeโ displays a 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 sets which color components to display. Default is1, which means only luma or red color component if input is in RGB colorspace. If it's set, for example, to7it will display all 3 (if) available color components.envelope,eโnoneโ 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,fโlowpassโ 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 sets 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 sets graticule opacity.flags,flโ sets graticule flags.numbersโ draw numbers above lines. By default enabled.dotsโ draw dots instead of lines.
scale,sโ sets scale used for displaying graticule.digitalmillivoltsire
Default is digital.
bgopacity,bโ sets background opacity.tint0,t0tint1,t1โ set tint for output. Only used withlowpassfilter and when display is notoverlayand input pixel formats are not RGB.fitmode,fmโ sets 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 to1/1.sizeโ set sample aspect ratio to match input size of video
Default is none.
inputโ sets input formats for filter to pick from. Can beall, for selecting from all available formats, orfirst, for selecting first available format. Default isfirst.
๐ง weave, doubleweave ๐ง
The weave takes a field-based video input and joins each two sequential fields into a single frame, producing a new double height clip with half the frame rate and half the frame count. Two fields becoming one frame? That's called commitment ๐
The doubleweave works the same as weave but without halving frame rate and frame count.
It accepts the following option:
first_fieldโ sets first field. Available values are:top,tโ set the frame as top-field-first.bottom,bโ set the frame as bottom-field-first.
Examples โญ
- Interlace video using
selectandseparatefieldsfilter. Look at this lil pipeline go:
separatefields,select=eq(mod(n,4),0)+eq(mod(n,4),3),weave
๐ xbr ๐
Applies 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>. Pixel art girlies stay winning ๐จ
It accepts the following option:
nโ sets the scaling dimension:2for"2xBR",3for"3xBR"and4for"4xBR". Default is3.
๐ฆ xcorrelate ๐ฆ
Applies normalized cross-correlation between the first and second input video stream.
Second input video stream dimensions must be lower than first input video stream. That's the rule, bestie, don't fight it.
The filter accepts the following options:
planesโ sets which planes to process.secondaryโ sets which secondary video frames will be processed from the second input video stream, can befirstorall. Default isall.
The xcorrelate filter also supports the framesync options. Fancy.
๐ฅ xfade ๐ฅ
Applies cross fade from one input video stream to another input video stream. The cross fade is applied for the specified duration. It's giving dramatic transition, main character energy โจ
Both inputs must be constant frame-rate and have the same resolution, pixel format, frame rate and timebase. No exceptions.
The filter accepts the following options:
transitionโ set one of available transition effects:customfadewipeleftwiperightwipeupwipedownslideleftsliderightslideupslidedowncirclecroprectcropdistancefadeblackfadewhiteradialsmoothleftsmoothrightsmoothupsmoothdowncircleopencircleclosevertopenvertclosehorzopenhorzclosedissolvepixelizediagtldiagtrdiagbldiagbrhlslicehrslicevuslicevdslicehblurfadegrayswipetlwipetrwipeblwipebrsqueezehsqueezevzoominfadefastfadeslowhlwindhrwindvuwindvdwindcoverleftcoverrightcoverupcoverdownrevealleftrevealrightrevealuprevealdown
Default transition effect is fade. ๐
durationโ sets the cross fade duration in seconds. Range is0to60seconds. Default duration is1second. โฑ๏ธoffsetโ sets the cross fade start relative to the first input stream, in seconds. Default offset is0.exprโ sets the expression for thecustomtransition effect. ๐ง
The expressions can use the following variables and functions:
X,Yโ the coordinates of the current sample.W,Hโ the width and height of the image.Pโ progress of the 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 of2seconds starting at offset of5seconds:
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. ๐ฏ like, the group chat votes and the middle opinion wins.
The filter accepts the following options:
inputsโ set number of inputs. Default is3. Allowed range is from3to255. If number of inputs is even number, than result will be mean value between two median values.planesโ set which planes to filter. Default value is15, by which all planes are processed.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 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. ๐
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> ๐
- 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 at24frames per second, with color format4:2:0, bit depth8, 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 depth8andtest_video.yuvwith bit depth10, both at60frames per second with color format4:2:0, 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. ๐งฑ like a collage but make it cinema.
All streams must be of same pixel format.
The filter accepts the following options:
inputsโ set number of input streams. Default is2.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 at0and 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. ๐จ
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. ๐จ
shortestโ if set to1, force the output to terminate when the shortest input terminates. Default value is0.fillโ if set to valid color, all unused pixels will be filled with that color. By default fill is set tonone, so it is disabled. ๐จ
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
ngl bestie, quick heads up before we keep it moving:
โ ๏ธ Note that if inputs are of different sizes, gaps or overlaps may occur. like, it's giving "we tried" โ not a crash, just a lil visual mess. ๐
yadif ๐ฆ
Deinterlace the input video (and yes, yadif means "yet another deinterlacing filter" โ the Unix world has a whole thing about naming stuff "yet another," iykyk ๐
).
It accepts the following parameters:
modeโ the interlacing mode to adopt, she takes one of these values:0,send_frameโ output one frame for each frame. one-to-one, no drama โจ1,send_fieldโ output 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. periodt. parityโ the picture field parity assumed for the input interlaced video. it accepts one of these: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. and lowkey important: if the interlacing is unknown or the decoder does not export this information, top field first will be assumed. ๐ซถ deintโ specify which frames to deinterlace. accepts one of these:0,allโ deinterlace all frames. every single one, no skip ๐1,interlacedโ only deinterlace frames marked as interlaced.
- The default value is
all.
yaepblur ๐ธ
Apply blur filter while preserving edges (yaepblur means "yet another edge preserving blur filter" โ see, the naming thing again ๐ญ). 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 bestie, actual cited paper, we're academic now ๐.
It accepts the following 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 โจ๏ธ
This filter supports same commands as options. slay.
zoompan ๐
Apply Zoom & Pan effect. main character energy fr.
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 number of frames the effect will last for a single input image. Default is90.sโ set the output image size, default is'hd720'.fpsโ set the output frame rate, default is'25'.
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. (not me getting aNAN, embarrassing ๐)out_time,time,otโ the output timestamp expressed in seconds.x,yโ last calculatedxandyposition fromxandyexpression for current input frame.px,pyโxandyof last output frame of previous input frame, or0when there was not yet such frame (first input frame).zoomโ last calculated zoom fromzexpression for current input frame.pzoomโ last calculated zoom of last output frame of previous input frame.durationโ number of output frames for current input frame. calculated fromdexpression for each input frame.pdurationโ number of output frames created for previous input frame.aโ rational number: input width / input height.sarโ sample aspect ratio.darโ display aspect ratio.
Examples ๐ฅ
- Zoom in up to 1.5x and pan at same time to some spot near center of 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 center of 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 center of 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 ๐
Scale (resize) 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. (compile-time flag, so don't come for me if it's not there ๐)
The zscale filter forces the output display aspect ratio to be the same as the input, by changing the output sample aspect ratio. iconic behaviour honestly.
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 โจ
The filter accepts the following options.
width,w,height,hโ set the output video dimension expression. Default value is the input dimension.- If the
widthorwvalue is0, the input width is used for the output. If theheightorhvalue is0, the input height is used for the output. - If one and only one of the values is
-nwithn >= 1, thezscalefilter 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 bynand adjust the value if necessary. - If both values are
-nwithn >= 1, the behavior will be identical to both values being set to0as previously detailed. - See below for the list of accepted constants for use in the dimension expression.
- If the
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 formatyuv422phsubis2andvsubis1.ohsub,ovsubโ horizontal and vertical output chroma subsample values. For example for the pixel formatyuv422phsubis2andvsubis1.
Commands ๐
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. (so it just, like, stays. no crash, no fuss ๐ซถ)
๐ง CUDA VIDEO FILTERS ๐ง
To enable CUDA and/or NPP filters please refer to configuration guidelines for CUDA and for CUDA NPP filters.
Running CUDA filters requires you to initialize a hardware device and to pass that device to all filters in any filter graph. no shortcuts bestie, the whole graph needs the device ๐
-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 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
Since CUDA filters operate exclusively on GPU memory, frame data must sometimes be uploaded (<code>hwupload</code>) to hardware surfaces associated with the appropriate CUDA device before processing, and downloaded (<code>hwdownload</code>) back to normal memory afterward, if required. Whether <code>hwupload</code> or <code>hwdownload</code> is necessary depends on the specific workflow:
- If the input frames are already in GPU memory (e.g., when using
-hwaccel cudaor-hwaccel_output_format cuda), explicit use ofhwuploadis not needed, as the data is already in the appropriate memory space. - If the input frames are in CPU memory (e.g., software-decoded frames or frames processed by CPU-based filters), it is necessary to use
hwuploadto transfer the data to GPU memory for CUDA processing. - If the output of the CUDA filters needs to be further processed by software-based filters or saved in a format not supported by GPU-based encoders,
hwdownloadis required to transfer the data back to CPU memory.
Note that hwupload uploads data to a surface with the same layout as the software frame, so it may be necessary to add a format filter immediately before hwupload to ensure the input is in the correct format. Similarly, hwdownload may not support all output formats, so an additional format filter may need to be inserted immediately after hwdownload in the filter graph to ensure compatibility.
๐ CUDA ๐
Below is a description of the currently available Nvidia CUDA video filters.
Prerequisites:
- Install Nvidia CUDA Toolkit
Note: If FFmpeg detects the Nvidia CUDA Toolkit during configuration, it will enable CUDA filters automatically without requiring any additional flags. If you want to explicitly enable them, use the following options:
- Configure FFmpeg with
--enable-cuda-nvcc --enable-nonfree. - Configure FFmpeg with
--enable-cuda-llvm. Additional requirement:llvmlib must be installed.
๐ bilateral_cuda ๐
CUDA accelerated bilateral filter, an edge preserving filter. This filter is mathematically accurate thanks to the use of GPU acceleration. For best output quality, use one to one chroma subsampling, i.e. yuv444p format.
The filter accepts the following options:
sigmaSโ Set sigma of gaussian function to calculate spatial weight, also called sigma space. Allowed range is0.1to512. Default is0.1.sigmaRโ Set sigma of gaussian function to calculate color range weight, also called sigma color. Allowed range is0.1to512. Default is0.1.window_sizeโ Set window size of the bilateral function to determine the number of neighbours to loop on. If the number entered is even, one will be added automatically. Allowed range is1to255. Default is1.
โจ Examples โจ
- 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
๐ฆ bwdif_cuda ๐ฆ
Deinterlace the input video using the bwdif algorithm, but implemented in CUDA so that it can work as part of a GPU accelerated pipeline with nvdec and/or nvenc.
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 chromakey_cuda ๐
CUDA accelerated YUV colorspace color/chroma keying.
This filter works like normal chromakey filter but operates on CUDA frames. For more details and parameters see chromakey.
โจ Examples โจ
- 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
๐ธ colorspace_cuda ๐ธ
CUDA accelerated implementation of the colorspace filter.
It is by no means feature complete compared to the software colorspace filter, and at the current time only supports color range conversion between jpeg/full and mpeg/limited range.
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
๐ overlay_cuda ๐
Overlay one video on top of another.
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 on which the second input is overlaid.
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,W;main_h,Hโ The main input width and height.overlay_w,w;overlay_h,hโ The overlay input width and height.x,yโ The computed values for x and y. 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.tโ The timestamp of the main input frame, expressed in seconds,NANif unknown.
Default value is "0" for both expressions.
evalโ Set when the expressions for x and y are 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.
๐ซถ pad_cuda ๐ซถ
Add paddings to an input video stream using CUDA.
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 available options, please see the documentation for the pad filter.
โจ Examples โจ
- 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
โญ scale_cuda โญ
Scale (resize) and convert (pixel format) the input video, using accelerated CUDA kernels. 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.
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 of"auto"(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 identical scale filter options.reset_sarโ Works the same as the identical scale filter option.
โจ Examples โจ
- Scale to 720p, aspect ratio preserved, and make sure the output is
yuv420p.
scale_cuda=-2:720:format=yuv420p
- Upscale to 4K with the nearest neighbour algorithm.
scale_cuda=4096:2160:interp_algo=nearest
- Do zero conversion, zero scaling โ just copy every input frame into a freshly allocated one. This is lowkey a lifesaver when a filter + encode chain would otherwise drain the decoder's frame pool dry. ๐ญ
scale_cuda=passthrough=0
thumbnail_cuda ๐ผ๏ธ
Picks the most representative frame out of a run of consecutive frames, using CUDA. Bestie, it literally just looks at a batch and goes "this one. this is the one." ๐
It accepts these options:
nโ the frames batch size to analyze. Out of a set ofnframes the filter picks one, then handles the next batch ofnframes, and so on till the end. Default is100.
Heads up: since the filter keeps track of the whole frames sequence, a bigger n means higher memory usage โ so a high value is not recommended. Don't be greedy. ๐
Example
- Thumbnails get extracted from every
n=150-frame batch, one pick per batch. Then the chosen frames are 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 โจ
Deinterlaces your input video using the yadif algorithm โ except it's implemented in CUDA, so it can chill as part of a GPU accelerated pipeline with nvdec and/or nvenc. Same brain, GPU body. ๐ซถ
It accepts these parameters:
modeโ the interlacing mode to adopt. Takes 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.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 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.
deintโ specify which frames to deinterlace. Accepts one of these:0,allโ deinterlace all frames.1,interlacedโ only deinterlace frames marked as interlaced.
The default value is all.
๐ CUDA NPP ๐
Below is a description of the currently available NVIDIA Performance Primitives (libnpp) video filters. Fancy library, fancy filters. ๐
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 the exact same way as it does for the scale filter. ๐
The following 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 these: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 enables decreasing or increasing the output video width or height when necessary, to keep the original aspect ratio. Possible values:disableโ scale the video as specified and disable 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 case for this: when you know a specific device's maximum allowed resolution, you can use this to limit the output video to that while retaining the aspect ratio. Say device A allows 1280x720 playback and your video is 1920x800 โ use this option (set to decrease) and pass 1280x720 on the command line, and the output becomes 1280x533. Slay. โจ
Please note this is a different thing than specifying-1forworhโ you still need to specify the output resolution for this option to work. Don't skip that step, bestie. ๐
force_divisible_byโ makes sure 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. The video's aspect ratio may be slightly modified. ๐ฌ
It can be handy if you need a video to fit within or exceed a defined resolution using force_original_aspect_ratio, but you've also got encoder restrictions on width or height divisibility.
reset_sarโ works the same as the identicalscalefilter option.evalโ specify when to evaluate the width and height expression. Accepts these values:initโ only evaluate expressions once during 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, or NaN if this info is unavailable and/or meaningless (for example in the case of synthetic video). Only available witheval=frame. Deprecated, do not use. โ ๏ธ
scale2ref_npp
Uses the NVIDIA Performance Primitives (libnpp) to scale (resize) the input video, based on a reference video. The main character is the reference, honestly. ๐
See the scale_npp filter for 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 the following 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, or NaN if this info is unavailable and/or meaningless (for example in the 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 ๐ฅ
Uses the NVIDIA Performance Primitives (libnpp) to perform image sharpening with border control. Crispy edges, no cap.
The following additional options are accepted:
border_typeโ the type of sampling to be used at frame borders. One of these:replicateโ replicate pixel values.
transpose_npp ๐ฆ
Transposes rows with columns in the input video, and optionally flips it. For more in-depth examples, see the transpose video filter โ it shares mostly the same options.
It accepts these parameters:
dirโ specify 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 do 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 (when height >= width).landscapeโ preserve landscape geometry (when width >= height).
๐ง OPENCL VIDEO FILTERS ๐ง
Below is a description of the currently available OpenCL video filters. GPU girlies, this one's for you. ๐
To enable compilation of these filters you need to configure FFmpeg with --enable-opencl.
Running OpenCL filters requires you to initialize a hardware device and to pass that device to all filters in any filter graph. Like introducing your friend to the whole group chat. ๐ซถ
-init_hw_device opencl[=name][:device[,key=value...]]โ initialise a new hardware device of typeopenclcalled 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 info see https://www.ffmpeg.org/ffmpeg.html#Advanced-Video-options.
- Example of choosing the first device on the second platform and running
avgblur_openclwith default parameters on it.
-init_hw_device opencl=gpu:1.0 -filter_hw_device gpu -i INPUT -vf "hwupload, avgblur_opencl, hwdownload" OUTPUT
Okay bestie, OpenCL lore drop ๐ซถ: these filters literally canโt reach frame data sitting in normal memory, so all of it needs to be uploaded (hwupload) to hardware surfaces connected to the right device before itโs used, then downloaded (hwdownload) back to normal memory. Note that hwupload uploads to a surface with the same layout as the software frame, so you may need to add a format filter immediately before to get the input into the right format. And hwdownload does not support all formats on output โ you may need to insert an extra format filter immediately after it in the graph to get output in a supported format. ๐
avgblur_opencl ๐
Apply average blur filter.
The filter accepts these options:
sizeXโ horizontal radius size. Range is[1, 1024], default is1.planesโ which planes to filter. Default is0xf, which means all planes get processed.sizeYโ vertical radius size. Range is[1, 1024], default is0. If zero, thesizeXvalue is used.
Example:
- Apply average blur filter with horizontal and vertical size of
3, setting each pixel of the output to the average value of the7x7region 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
boxblur_opencl ๐ธ
Apply a boxblur algorithm to the input video.
It accepts these parameters:
luma_radius,lrluma_power,lpchroma_radius,crchroma_power,cpalpha_radius,aralpha_power,ap
Okay, description time:
luma_radius,lr;chroma_radius,cr;alpha_radius,arโ set an expression for the box radius in pixels used to blur the corresponding input plane. The radius value must be a non-negative number, and must not be greater than the value of the expressionmin(w,h)/2for the luma and alpha planes, and ofmin(cw,ch)/2for the chroma planes. Default value forluma_radiusis2. If not specified,chroma_radiusandalpha_radiusdefault to the corresponding value set forluma_radius. The expressions can contain these 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,hsubis2andvsubis1.
luma_power,lp;chroma_power,cp;alpha_power,apโ specify how many times the boxblur filter is applied to the corresponding plane. Default value forluma_poweris2. If not specified,chroma_powerandalpha_powerdefault to the corresponding value set forluma_power. A value of0will disable the effect.
Examples:
Apply boxblur filter, setting each pixel of the output to the average value of box radii 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
2and luma, chroma, and alpha power set to3. The filter will run3times with box radius set to2for 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_powerto1,chroma_radiusto4,chroma_powerto5,alpha_radiusto3andalpha_powerto7.
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
colorkey_opencl ๐
RGB colorspace color keying.
The filter accepts these 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 pixel color is to the key color.
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
convolution_opencl โจ
Apply convolution of 3x3, 5x5, 7x7 matrix.
The filter accepts these options:
0m,1m,2m,3mโ set matrix for each plane. Matrix is sequence of9,25or49signed 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
erosion_opencl ๐ฆ
Apply erosion effect to the video.
This filter replaces the pixel by the local(3x3) minimum.
It accepts these 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 local3x3coordinates region centered onx:
1 2 3
4 x 5
6 7 8
Example:
- Apply erosion filter with
threshold0set to30,threshold1set40,threshold2set to50andcoordinatesset to231, setting each pixel of the output to the local minimum between pixels:1,2,3,6,7,8of the3x3region 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 minus threshold of corresponding plane.
-i INPUT -vf "hwupload, erosion_opencl=30:40:50:coordinates=231, hwdownload" OUTPUT
deshake_opencl ๐
Feature-point based video stabilization filter.
The filter accepts these 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 verbosetoffmpeg. Viewing point matches in the output video is only supported for RGB input. Defaults to0.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
dilation_opencl ๐ซถ
Apply dilation effect to the video.
This filter replaces the pixel by the local(3x3) maximum.
It accepts the following options:
threshold0,threshold1,threshold2,threshold3โ the cap on how much each plane is allowed to change ๐ Range is[0, 65535]and the default is65535. And if you set it to0, that plane literally just stays exactly as it was, untouched, no notes ๐coordinatesโ a flag saying which pixels we're allowed to peek at ๐ Range is[0, 255], default255โ which means all eight neighbors get used. Each flag points at a spot in the local 3x3 neighborhood centered onx:
1 2 3
4 x 5
6 7 8
Example โจ
- Apply the dilation filter with
threshold0set to30,threshold1set to40,threshold2set to50, andcoordinatesset to231โ which sets every output pixel to the local maximum among pixels1,2,3,6,7,8of the 3x3 region centered on it in the input ๐ฏ And if the difference between the input pixel and that local max is more than the threshold of the corresponding plane, the output pixel gets set to input pixel + that plane's threshold:
-i INPUT -vf "hwupload, dilation_opencl=30:40:50:coordinates=231, hwdownload" OUTPUT
nlmeans_opencl ๐ง
Non-local Means denoise filter, but through OpenCL ๐ซถ This filter accepts the same options as nlmeans.
overlay_opencl ๐
Overlay one video on top of another, bestie. Classic.
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 ๐ Heads up though: this filter requires the same memory layout for all the inputs, so you might need a format conversion first ngl.
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.
Examples ๐ธ
- 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 the same memory layout for color channels, and the overlay has an additional alpha plane โ like
INPUTisyuv420pand theLOGOisyuva420p:
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuva420p, hwupload[b], [a][b]overlay_opencl, hwdownload" OUTPUT
pad_opencl ๐ฆ
Adds padding to the input image and drops the original input at the x, y coordinates you give it. It's giving "scrapbook page with a cute margin" energy honestly ๐
It accepts the following options:
width,wandheight,hโ specify an expression for the size of the output image with the paddings added โจ If the value for width or height is0, the corresponding input size gets used for the output instead. Also: the width expression can reference the value set by the height expression, and vice versa โ they're mutual besties like that ๐ซถ The default value ofwidthandheightis0.xandyโ specify the offsets for placing the input image inside the padded area, relative to the top/left border of the output image. The x expression can reference the value set by the y expression, and vice versa. Default value ofxandyis0. And ifxoryevaluate to a negative number, they get changed so the input image is centered on the padded area ๐ฏcolorโ the color of the padded area. For the syntax of this option, check theColorsection in theffmpeg-utilsmanual.aspectโ pad to an aspect instead of 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 same asin_wandin_h.out_w,out_hโ the output width and height (i.e. the size of the padded area), as specified by thewidthandheightexpressions.ow,ohโ 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, which is the same as(iw / ih) * sar.
prewitt_opencl ๐ฅ
Applies the Prewitt operator (https://en.wikipedia.org/wiki/Prewitt_operator) to the input video stream. Edge detection slay ๐
The filter accepts the following options:
planesโ set which planes to filter. Default value is0xf, which means all planes get processed.scaleโ set the value that gets multiplied with the filtered result. Range is[0.0, 65535]and default value is1.0.deltaโ set the value that gets added to the filtered result. Range is[-65535, 65535]and default value is0.0.
Example โญ
- Apply the Prewitt operator with
scaleset to2anddeltaset to10:
-i INPUT -vf "hwupload, prewitt_opencl=scale=2:delta=10, hwdownload" OUTPUT
program_opencl ๐
Filter video using an OpenCL program. This one's the main character fr โ you bring the code, it runs it ๐ง
sourceโ OpenCL program source file.kernelโ kernel name in the 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 ๐ซถ
The program source file must contain a kernel function with the given name, which gets run once for each plane of the output โจ Each run on a plane is enqueued as a separate 2D global NDRange with one work-item for every pixel to be generated. So the global ID offset for each work-item is literally the coordinates of a pixel in the destination image. iykyk.
The kernel function needs to take the following arguments:
- Destination image,
__write_only image2d_t. This image becomes the output, and the kernel should write all of it. - Frame index,
unsigned int. This is a counter starting from zero and going up 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 can't be written to ๐
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 that increases with the index counter. Pixel values get linearly interpolated by the sampler, and the output doesn't need to have the same dimensions as the input ๐
__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 how much of each input gets used varying with the index counter ๐
__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));
}
remap_opencl ๐
Remap pixels using the 2nd: Xmap and 3rd: Ymap input video stream. Yes, that's the numbering โ 2nd and 3rd ๐ซถ
So the destination pixel at position (X, Y) gets picked from the source (x, y) position where x = Xmap(X, Y) and y = Ymap(X, Y). And if the mapping values are out of range, a zero value for that pixel gets used for the destination pixel ๐
Xmap and Ymap input video streams must be of the same dimensions, and the output video stream will have Xmap/Ymap video stream dimensions. Also, Xmap and Ymap input video streams are 32bit float pixel format, single channel ๐
interpโ specify the interpolation used for remapping pixels. Allowed values arenearandlinear. Default value islinear.fillโ specify the color of the unmapped pixels. For the syntax of this option, check theColorsection in theffmpeg-utilsmanual. Default color isblack.
roberts_opencl ๐
Applies the Roberts cross operator (https://en.wikipedia.org/wiki/Roberts_cross) to the input video stream. More edge detection, we love to see it โจ
The filter accepts the following options:
planesโ set which planes to filter. Default value is0xf, which means all planes get processed.scaleโ set the value that gets multiplied with the filtered result. Range is[0.0, 65535]and default value is1.0.deltaโ set the value that gets added to the filtered result. Range is[-65535, 65535]and default value is0.0.
Example ๐
- Apply the Roberts cross operator with
scaleset to2anddeltaset to10:
-i INPUT -vf "hwupload, roberts_opencl=scale=2:delta=10, hwdownload" OUTPUT
๐ธ sobel_opencl
Okay so this one literally just applies the Sobel operator (you know, the edge-detection icon โ <https://en.wikipedia.org/wiki/Sobel_operator>) to your input video stream. Edge vibes only. โจ
It takes exactly one option:
planesโ tells it which planes to filter. Default is0xf, which means all the planes get processed. slay.scaleโ a value that gets multiplied with the filtered result. Range is[0.0, 65535]and the default is1.0.deltaโ a value that gets added to the filtered result. Range is[-65535, 65535]and the default is0.0.
๐ Example
- Apply the sobel operator with
scaleset to 2 anddeltaset to 10:
-i INPUT -vf "hwupload, sobel_opencl=scale=2:delta=10, hwdownload" OUTPUT
๐ tonemap_opencl
This one does HDR (PQ/HLG) โ SDR conversion with tone-mapping. It's giving "make your HDR look right on a normal screen" realness. ๐
It accepts these parameters:
tonemapโ specify which tone-mapping operator to use. Same as thetonemapoption intonemap.paramโ tunes the tone mapping algorithm. Same as theparamoption intonemap.desatโ applies desaturation for highlights that go past this level of brightness. The higher you set it, the more color info gets preserved. It helps stop super-highlights from looking unnaturally blown out by (smoothly) turning them into white instead. Result: images feel more natural, but you lose info about those out-of-range colors. The default value is0.5, and ngl the algorithm here is a little different from the cpu versiontonemaphas right now. Setting it to0.0disables this option entirely.thresholdโ the tonemapping algorithm params get fine-tuned per scene, and this threshold is what detects whether the scene actually changed or not. If the distance between the current frame's average brightness and the current running average exceeds the threshold value, it re-calculates the scene average and peak brightness. Default 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.
lowkey the original says "Possible value are" for matrix โ that's just how it's written, don't come for me ๐ซถ
๐ Example
- Convert HDR (PQ/HLG) video to bt2020-transfer-characteristic p010 format using the linear operator:
-i INPUT -vf "format=p010,hwupload,tonemap_opencl=t=bt2020:tonemap=linear:format=p010,hwdownload,format=p010" OUTPUT
๐ฆ unsharp_opencl
Sharpen or blur your input video. Two moods, one filter, iconic. โจ
It accepts these parameters:
luma_msize_x,lxโ set the luma matrix horizontal size. Range is[1, 23]and the default is5.luma_msize_y,lyโ set the luma matrix vertical size. Range is[1, 23]and the default is5.luma_amount,laโ set the luma effect strength. Range is[-10, 10]and the default is1.0. Negative values blur the input video, positive values sharpen it, and a value of zero disables the effect completely.chroma_msize_x,cxโ set the chroma matrix horizontal size. Range is[1, 23]and the default is5.chroma_msize_y,cyโ set the chroma matrix vertical size. Range is[1, 23]and the default is5.chroma_amount,caโ set the chroma effect strength. Range is[-10, 10]and the default is0.0. Negative values blur the input video, positive values sharpen it, zero disables the effect.
Every single parameter is optional and defaults to the equivalent of the string '5:5:1.0:5:5:0.0'. iykyk. ๐
๐ Examples
- Apply a 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
โญ xfade_opencl
Cross fade two videos together with a custom transition effect, using OpenCL. Main character transition energy fr fr. ๐ฅ
It accepts these options:
transitionโ set one of the possible transition effects:customโ selects the custom transition effect; the actual transition description gets picked from thesourceandkerneloptions.fadewipeleftwiperightwipeupwipedownslideleftsliderightslideupslidedown
Default transition is fade.
sourceโ OpenCL program source file for the custom transition.kernelโ set the name of the kernel to use for the custom transition from the program source file.durationโ set duration of the video transition.offsetโ set the time of the start of the transition relative to the first video.
Okay so here's how the custom thing works ๐: the program source file must contain a kernel function with the given name, and it gets run once for each plane of the output. Each run on a plane is enqueued as a separate 2D global NDRange with one work-item for each pixel to be generated. So the global ID offset for each work-item is literally the coordinates of a pixel in the destination image. periodt.
The kernel function needs to take these arguments:
- Destination image,
__write_only image2d_t. This image becomes the output โ 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.
๐ Example programs
- Apply the 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);
}
๐ and that's the whole custom-kernel situation โ copy that shape and you're golden.
๐ VAAPI VIDEO FILTERS ๐
Okay so VAAPI video filters are normally besties with the VAAPI decoder and the VAAPI encoder โ like they literally show up as a trio. Here's the whole rundown of the VAAPI video filters, no gatekeeping.
To even compile these filters you gotta configure FFmpeg with --enable-vaapi. That's the vibe check for the build, fr.
And to actually use vaapi filters you need to set up the vaapi device correctly โ no shortcuts, bestie. For more info, please read https://trac.ffmpeg.org/wiki/Hardware/VAAPI.
overlay_vaapi
Overlay one video on the top of another. Classic main character + supporting character situation.
It takes two inputs and has one output. The first input is the "main" video on which the second input is overlaid. ๐
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 the overlaid video on the main video. Default values areoverlay_iwforwandoverlay_ih*w/overlay_iwforh.
The expressions can contain the following parameters:
main_w,W,main_h,Hโ The main input width and height.overlay_iw,overlay_ihโ The overlay input width and height.overlay_w,w,overlay_h,hโ The overlay output width and height.overlay_x,x,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. (Yes, it's backwards from your gut feeling, iykyk.)eof_actionโ See framesync.shortestโ See framesync.repeatlastโ See framesync.
This filter also supports the framesync options.
Examples
- Overlay an image
LOGOat the top-left corner of theINPUTvideo. Both inputs for this filter areyuv420pformat.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuv420p, hwupload[b], [a][b]overlay_vaapi" OUTPUT
- Overlay an image
LOGOat the offset(200, 100)from the top-left corner of theINPUTvideo. The inputs have same memory layout for color channels, the overlay has additional alpha plane, likeINPUTisyuv420p, and theLOGOisyuva420p.
-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
tonemap_vaapi
Perform HDR-to-SDR or HDR-to-HDR tone-mapping. It currently only accepts HDR10 as input โ that's the whole guest list rn. ๐
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 set 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. ๐lightโ 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.
Example
- Convert HDR(HDR10) video to bt2020-transfer-characteristic p010 format
tonemap_vaapi=format=p010:t=bt2020-10
- Convert HDR video to HDR video
tonemap_vaapi=display=7500\ 3000|34000\ 16000|13250\ 34500|15635\ 16450|500\ 10000000
Notice the backslash-space escapes in that display value โ copy it exactly, don't get cute with it. ๐
hstack_vaapi
Stack input videos horizontally. Side-by-side slay.
This is the VA-API variant of the hstack filter โ each input stream may have different height, and this filter will scale down/up each input stream while keeping the original aspect. So nobody gets stretched, we love to see it. โจ
It accepts the following options:
inputsโ See hstack.shortestโ See hstack.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.
vstack_vaapi
Stack input videos vertically. Same energy, but stacked up.
This is the VA-API variant of the vstack filter โ 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 See vstack.shortestโ See vstack.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.
xstack_vaapi
Stack video inputs into custom layout. This is the "I make the rules" one, highkey iconic.
This is the VA-API variant of the xstack filter, each input stream may have different size, this filter will scale down/up each input stream to the given output size, or the size of the first input stream.
It accepts the following options:
inputsโ See xstack.shortestโ See xstack.layoutโ See xstack. 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 See xstack.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 the "Video size" section in the ffmpeg-utils manual.fillโ See xstack.
pad_vaapi
Add paddings to the input image, and place the original input at the provided x, y coordinates. It's giving scrapbook page with a border, honestly. ๐
It accepts the following options:
width,w,height,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. ๐ (built-in centering, we stan)colorโ Specify the color of the padded area. For the syntax of this option, check the "Color" section 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 as in_w and in_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 as out_w and out_h.x,yโ The x and y offsets as specified by the x and y expressions, orNANif not yet specified.aโ same asiw / ihsarโ input sample aspect ratiodarโ input display aspect ratio, it is the same as(iw / ih) * sar
drawbox_vaapi
Draw a colored box on the input image. Arts and crafts time, bestie. ๐๏ธ
It accepts the following parameters:
x,yโ The expressions which specify the top left corner coordinates of the box. It defaults to0.width,w,height,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 the "Color" section 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,ih,in_w,iwโ The input width and height.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.
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
That last one has negative offsets and math in it โ literally just paste it as-is and let the expressions cook. ๐ฅ
๐ VIDEOTOOLBOX VIDEO FILTERS ๐
Okay bestie, so these are the VideoToolbox video filters, and they're basically the Apple-silicon-era glow-up of video filtering. โจ
The VideoToolbox filter depends on the VideoToolbox framework, and it's auto detected when building ffmpeg for an Apple platform such as macOS. If autodetect is disabled, just add --enable-videotoolbox to configure. Easy. ๐
โจ scale_vt โจ
Scales and converts the color parameters using VTPixelTransferSession. It's giving "resize but make it Apple-native." ๐ฆ
The filter accepts the following options:
w,hโ Set the output video dimension expression. Default value is the input dimension. (So if you don't touch it, it just matches what came in. Iconic lazy-girl behavior, honestly.) ๐color_matrixโ Set the output colorspace matrix.color_primariesโ Set the output color primaries.color_transferโ Set the output transfer characteristics.
๐ Examples ๐
- 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, the way that command does HDRโSDR and halves the size in one -vf? Chef's kiss. ๐ฅ
๐ธ transpose_vt ๐ธ
Transposes rows with columns in the input video, and optionally flips it too. For more in-depth examples, go check out the transpose video filter โ it shares mostly the same options. (Sibling energy fr fr. ๐ฏ)
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) ๐ซclockโ 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) ๐ซถportraitโ Preserve portrait geometry (whenheight >= width).landscapeโ Preserve landscape geometry (whenwidth >= height).
Lowkey important: passthrough only skips the transposition when the geometry matches โ it's not out here skipping filters for fun. Read the value, bestie. ๐
The way dir defaults to cclock_flip is such a quirky main-character choice, but periodt, that's the spec. ๐
๐ VULKAN VIDEO FILTERS
Okay bestie, gather round โ here's the rundown on all the Vulkan video filters we currently have, and yes they are exactly as extra as they sound. โจ
First things first: to even compile these filters you gotta configure FFmpeg with --enable-vulkan and either --enable-libglslang or --enable-libshaderc. No shortcuts, no cap. ๐
And running Vulkan filters? It literally requires you to initialize a hardware device and then pass that device to all filters in any filter graph. Like, all of them. Every single one. It's giving "everybody in the group chat needs to be on the same page." ๐ซถ
-init_hw_device vulkan[=name][:device[,key=value...]]โ Initialise a new hardware device of typevulkancalled name, using the given device parameters and options in key=value. The following options are supported:debugโ Switches validation layers on if set to1.linear_imagesโ Allocates linear images. Does not apply to decoding.disable_multiplaneโ Disables multiplane images. Does not apply to decoding.avoid_host_importโ Avoids the use of dynamic host memory imports, in favor of a regularmemcpy()into a previously mapped buffer.
-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> ๐
- ๐ฅ Example of choosing the first device and running
nlmeans_vulkanfilter with default parameters on it.
-init_hw_device vulkan=vk:0 -filter_hw_device vk -i INPUT -vf "hwupload,nlmeans_vulkan,hwdownload" OUTPUT
Okay so here's the tea โ โ Vulkan filters are not able to access frame data in normal memory. 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. Note that hwupload will upload to a frame with the same layout as the software frame, so it may be necessary to add a format filter immediately before to get the input into the right format โ and hwdownload does not support all formats on the output. It is usually necessary to insert an additional format filter immediately following in the graph to get the output in a supported format. ๐
๐ธ avgblur_vulkan
Apply an average blur filter, implemented on the GPU using Vulkan.
The filter accepts the following options:
sizeXโ Set horizontal radius size. Range is[1, 32]and default value is3.sizeYโ Set vertical radius size. Range is[1, 32]and default value is3.planesโ Set which planes to filter. Default value is0xf, by which all planes are processed.
๐ฆ blend_vulkan
Blend two Vulkan frames into each other.
The blend filter takes two input streams and outputs one stream, the first input is the "top" layer and second input is "bottom" layer. By default, the output terminates when the longest input terminates.
A description of the accepted options follows.
c0_modec1_modec2_modec3_modeall_mode
Set blend mode for specific pixel component or all pixel components in case of all_mode. Default value is normal.
Available values for component modes are:
normalmultiply
๐ bwdif_vulkan
Deinterlacer using bwdif, the "Bob Weaver Deinterlacing Filter" algorithm, implemented on the GPU using Vulkan.
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 chromaber_vulkan
Apply an effect that emulates chromatic aberration. Works best with RGB inputs, but provides a similar effect with YCbCr inputs too. โจ
dist_xโ Horizontal displacement multiplier. Each chroma pixel's position will be multiplied by this amount, starting from the center of the image. Default is0.dist_yโ Similarly, this sets the vertical displacement multiplier. Default is0.
โญ color_vulkan
Video source that creates a Vulkan frame of a solid color. Useful for benchmarking, or overlaying. ๐
It accepts the following parameters:
colorโ The color to use. Either a name, or a hexadecimal value. The default value isblack.sizeโ The size of the output frame. Default value is1920x1080.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 is1/1.formatโ The pixel format of the output Vulkan frames. Default value isyuv444p.out_rangeโ Set the output YCbCr sample range.
This allows the autodetected value to be overridden as well as allows forcing 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. That's it, that's the whole vibe. ๐ช
๐ง hflip_vulkan
Flips an image horizontally.
๐ง flip_vulkan
Flips an image along both the vertical and horizontal axis. Double flip, double slay. ๐
๐ gblur_vulkan
Apply Gaussian blur filter on Vulkan frames.
The filter accepts the following options:
sigmaโ Set horizontal sigma, standard deviation of Gaussian blur. Default is0.5.sigmaVโ Set vertical sigma, if negative it will be same assigma. Default is-1.planesโ Set which planes to filter. By default all planes are filtered.sizeโ Set the kernel size along the horizontal axis. Default is19.sizeVโ Set the kernel size along the vertical axis. Default is0, which sets to use the same value assize.
๐ฅ nlmeans_vulkan
Denoise frames using Non-Local Means algorithm, implemented on the GPU using Vulkan. Supports more pixel formats than nlmeans or nlmeans_opencl, including alpha channel support. Iconic behaviour honestly. ๐
The filter accepts the following options.
sโ Set denoising strength for all components. Default is1.0. Must be in range[0.0, 100.0].pโ Set patch size for all planes. Default is7. Must be odd number in range[0, 99].rโ Set research size. Default is15. Must be odd number in range[0, 99].tโ Set parallelism. Default is8. Must be a number in the range[1, 64]. Larger values will use more VRAM but may not result in greater speed. The optimal value is hardware and input dependent.s0,s1,s2,s3โ Set denoising strength for a specific component. Default is1.0, equal tos. Must be in range[0.0, 100.0].0.0disables denoising in that component.p0,p1,p2,p3โ Set patch size for a specific component. Default is7, equal top. Must be odd number in range[0, 99].
๐ overlay_vulkan
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 all inputs to use the same pixel format. So, format conversion may be needed. ๐ญ
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 transpose_vulkan
Transpose rows with columns in the input video and optionally flip it. For more in depth examples see the transpose video filter, which shares mostly the same options.
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)clockโ Rotate by 90 degrees clockwise.cclockโ Rotate by 90 degrees counterclockwise.clock_flipโ Rotate by 90 degrees clockwise and vertically flip.
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 (whenheight >= width).landscapeโ Preserve landscape geometry (whenwidth >= height).
๐ QSV VIDEO FILTERS ๐
Okay so hereโs the tea on the currently available QSV video filters, bestie. โจ
To enable compilation of these filters you need to configure FFmpeg with --enable-libmfx or --enable-libvpl.
To use QSV filters, you need to setup the QSV device correctly. For more information, please read https://trac.ffmpeg.org/wiki/Hardware/QuickSync.
๐ hstack_qsv ๐
Stack input videos horizontally. Itโs the QSV variant of the hstack filter, and each input stream may have a different height โ this filter will scale down/up each input stream while keeping the original aspect. ๐
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.
๐ฆ vstack_qsv ๐ฆ
Stack input videos vertically. This is the QSV variant of the vstack filter, and each input stream may have a different width โ this filter will scale down/up each input stream while keeping the original aspect. ๐ธ
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 ๐
Stack video inputs into a custom layout. This is the QSV variant of the xstack filter. ๐
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_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 theVideo sizesection in the ffmpeg-utils manual.fillโ Seexstack.
๐ VIDEO SOURCES ๐
Below is a description of the currently available video sources. Letโs go, bestie. ๐ซถ
๐ buffer ๐
Buffer video frames, and make them available to the filter chain.
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 theVideo sizesection in the ffmpeg-utils manual.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
๐ง cellauto ๐ง
Create a pattern generated by an elementary cellular automaton. 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.
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 is 25.random_fill_ratio,ratioโ Set the random fill ratio for the initial cellular automaton row. It is a floating point number value ranging from 0 to 1, 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 between 0 andUINT32_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 from 0 to 255. Default value is 110.size,sโ Set the size of the output video. For the syntax of this option, check theVideo sizesection in the ffmpeg-utils manual.
If filename or pattern is specified, the size is set by default to the width of the specified initial state row, and the height is set to width * PHI.
If size is 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 to 320x518 (used for a randomly generated initial state).
scrollโ If set to 1, scroll the output upward when all the rows in the output have been already filled. If set to 0, the new generated row will be written over the top row just after the bottom row is filled. Defaults to 1.start_full,fullโ If set to 1, completely fill the output with generated rows before outputting the first frame. This is the default behavior, for disabling set the value to 0.stitchโ If set to 1, stitch the left and right row edges together. This is the default behavior, for disabling set the value to 0.
๐ Examples ๐
- Read the initial state from
pattern, and specify an output of size 200x400.
cellauto=f=pattern:s=200x400
- Generate a random initial row with a width of 200 cells, with a fill ratio of 2/3:
cellauto=ratio=2/3:s=200x200
- Create a pattern generated by rule 18 starting by a single alive cell centered on an initial row with width 100:
cellauto=p=@s=100x400:full=0:rule=18
- Specify a more elaborated initial pattern:
cellauto=p='@@ @ @@':s=100x400:full=0:rule=18
๐ฆ coreimagesrc ๐ฆ
Video source generated on GPU using Apple's CoreImage API on OSX.
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 theVideo sizesection in the ffmpeg-utils manual. 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.
๐ Examples ๐
- 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.
๐ ddagrab ๐
Captures the Windows Desktop via Desktop Duplication API.
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.
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 at 0.
Defaults to output 0.
draw_mouseโ Whether to draw the mouse cursor.
Defaults to true.
Only affects hardware cursors. If a game or application renders its own cursor, it'll always be captured.
okay so we're still in ddagrab land โ here are the rest of the options, no cap ๐
framerateโ Maximum framerate at which the desktop will be captured. The interval between successive frames will not be smaller than the inverse of theframerate. Whendup_framesis true (the default) and the desktop is not being updated often enough, the filter will duplicate a previous frame. Note: there is no background buffering going on, so when the filter is not polled often enough, the actual inter-frame interval may be significantly larger.
Defaults to 30 FPS.
video_sizeโ Specify the size of the captured video.
Defaults to the full size of the screen.
Cropped from the bottom/right if smaller than screen size.
offset_xโ Horizontal offset of the captured video.offset_yโ Vertical offset of the captured video.output_fmtโ Desired filter output format. Defaults to 8 Bit BGRA.
It accepts the following values:
autoโ Passes all supported output formats to DDA and returns what DDA decides to use.8bit,bgraโ 8 Bit formats always work, and DDA will convert to them if necessary.10bit,x2bgr10โ Filter initialization will fail if 10 bit format is requested but unavailable.
dup_framesโ When this option is set to true (the default), the filter will duplicate frames when the desktop has not been updated in order to maintain approximately constant target framerate. When this option is set to false, the filter will wait for the desktop to be updated (inter-frame intervals may vary significantly in this case).
โจ Examples โจ
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. 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, this can be achieved by specifying a smaller size and its offsets into the screen:
ddagrab=video_size=800x600:offset_x=100:offset_y=100
๐ gfxcapture ๐
Capture windows or monitors using Windows.Graphics.Capture API.
This source provides low overhead capture of application windows or entire monitors. The filter outputs hardware frames in "d3d11" format; use "hwdownload,format=" if system memory frames are required.
The window to be captured can be selected 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 provided expressions to be selected. The first matching window will be picked, in whatever order Windows returns them.
Explicit handles (hwnd, hmonitor) override pattern or index based selection. If neither handles nor a monitor index are given, the first window matching the provided regular expressions is captured.
This source does NOT hold a stable FPS. It returns frames at whatever rate the compositor provides them, only capped by themax_framerate. If you need a stable rate, you need to add anfpsfilter to drop/duplicate frames as needed.
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 Aswindow_title, but matched against the window class name.window_exeโ 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 is60 FPS. 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 a negative number is provided, the width will be 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 a negative number is provided, the height will be 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. (yes, the manpage says left here too โ we don't make the rules ๐ญ)crop_rightโ Crop this many pixels from the left side of the captured frames. (same energy ๐)crop_bottomโ Crop this many pixels from the left side of the captured frames. (the copy-paste is real ๐)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. Remaining area is filled with black.
scale_modeโ 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
โจ Examples โจ
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
๐ gradients ๐
Generate several gradients.
size,sโ Set frame size. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is"640x480".rate,rโ Set frame rate, expressed as number of frames per second. Default value is"25".c0,c1,c2,c3,c4,c5,c6,c7โ Set 8 colors. Default for each color is to pick a random one.x0,y0,y0,y1โ Set gradient line source and destination points. If negative or out of range, random ones are picked. (yes, the original literally listsy0twice, bestie 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 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.
speedโ Set speed of gradients rotation.type,tโ Set type of gradients. Available values are:linearradialcircularspiralsquare
Default type is linear.
๐ Commands ๐
This source supports the some above options as commands. (yes, โthe some aboveโ โ we're keeping it โจ)
๐ฆ mandelbrot ๐ฆ
Generate a Mandelbrot set fractal, and progressively zoom towards the point specified with start_x and start_y.
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 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 is"25".size,sโ Set frame size. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is"640x480".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.
๐งช mptestsrc
Okay so this one generates a bunch of test patterns โ literally the same ones the MPlayer test filter makes โจ. Main character energy for your encoding experiments.
The size of the generated video is fixed, and it's 512x512 โ no, you can't change it, bestie, that's the whole point. This source is useful in particular for testing encoding features ๐.
It accepts these options:
rate,rโ the frame rate of the sourced video, meaning the number of frames generated per second ๐ . Gotta 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. Default value is"25"โจ.duration,dโ sets the duration of the sourced video. See the Time duration section in theffmpeg-utils(1)manual for the accepted syntax ๐ซถ. If not specified, or if the expressed duration is negative, the video is supposed to be generated forever ๐ญ (no cap, forever-forever).test,tโ sets 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 is30๐
Default value is "all", which will cycle through the list of all tests ๐.
Some examples, because we love a demo:
mptestsrc=t=dc_luma
will generate a "dc_luma" test pattern ๐.
๐ง frei0r_src
Provides a frei0r source ๐ธ.
To enable compilation of this filter you need to install the frei0r header and configure FFmpeg with --enable-frei0r ๐ ๏ธ.
This source accepts the following parameters:
sizeโ the size of the video to generate. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual ๐.framerateโ the framerate of the generated video. It may be a string of the formnum/denor a frame rate abbreviation โฑ๏ธ.filter_nameโ the name of the frei0r source to load. For more information regarding frei0r and how to set the parameters, read the frei0r section in the video filters documentation ๐.filter_paramsโ a'|'-separated list of parameters to pass to the frei0r source ๐ซถ.
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
Generates a life pattern ๐ โ yes, that life.
This source is based on a generalization of John Conway's life game ๐งซ.
The sourced input represents a life grid, each pixel represents a cell which can be in one of two possible states: alive or dead ๐. Every cell interacts with its eight neighbours, which are the cells that are horizontally, vertically, or diagonally adjacent ๐.
At each interaction the grid evolves according to the adopted rule, which specifies the number of neighbor alive cells which will make a cell stay alive or born ๐ฃ. The rule option allows one to specify the rule to adopt.
This source accepts the following options:
filename,fโ set the file from which to read the initial grid state ๐. In the file, each non-whitespace character is considered an alive cell, and newline is used to delimit the end of each row. If this option is not specified, the initial grid is generated randomly ๐ฒ.rate,rโ set the video rate, that is the number of frames generated per second. Default is25โฑ๏ธ.random_fill_ratio,ratioโ set the random fill ratio for the initial random grid. It's a floating point number value ranging from0to1, defaults to1/PHI๐. It is ignored when a file is specified ๐.random_seed,seedโ set the seed for filling the initial random grid, 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 ๐ฐ.ruleโ set the life rule ๐.
A rule can be specified with a code of the kind SNS/BNB, where NS and NB are sequences of numbers in the range 0-8, NS specifies the number of alive neighbor cells which make a live cell stay alive, and NB the number of alive neighbor cells which make a dead cell to become alive (i.e. to "born") ๐ฃ. "s" and "b" can be used in place of "S" and "B", respectively.
Alternatively a rule can be specified by an 18-bits integer ๐ข. The 9 high order bits are used to encode the next cell state if it is alive for each number of neighbor alive cells, the low order bits specify the rule for "borning" new cells. Higher order bits encode for an higher number of neighbor cells. For example the number 6153 = "(12<<9)+9" specifies a stay alive rule of 12 and a born rule of 9, which corresponds to "S23/B03" ๐
.
Default value is "S23/B3", which is the original Conway's game of life rule, and will keep a cell alive if it has 2 or 3 neighbor alive cells, and will born a new cell if there are three alive cells around a dead cell ๐.
size,sโ set the size of the output video. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual ๐.
If filename is specified, the size is set by default to the same size of the input file. If size is set, it must contain the size specified in the input file, and the initial grid defined in that file is centered in the larger resulting area ๐ฏ.
If a filename is not specified, the size value defaults to "320x240" (used for a randomly generated initial grid) ๐ธ.
stitchโ if set to1, stitch the left and right grid edges together, and the top and bottom edges also. Defaults to1๐งต.moldโ set cell mold speed. If set, a dead cell will go fromdeath_colortomold_colorwith a step ofmold๐.moldcan have a value from0to255.life_colorโ set the color of living (or new born) cells ๐.death_colorโ set the color of dead cells. Ifmoldis set, this is the first color used to represent a dead cell ๐ค.mold_colorโ set mold color, for definitely dead and moldy cells ๐ฆ .
For the syntax of these 3 color options, check the "Color" section in the ffmpeg-utils manual ๐จ.
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) usingffplay:
ffplay -f lavfi life=s=300x200:mold=10:r=60:ratio=0.1:death_color=#C83232:life_color=#00ff00,scale=1200:800:flags=16
๐ซ๏ธ perlin
Generates Perlin noise โจ.
Perlin noise is a kind of noise with local continuity in space ๐. This can be used to generate patterns with continuity in space and time, e.g. to simulate smoke, fluids, or terrain ๐ฅ.
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 ๐ต. In this case the persistence option specify the ratio of the amplitude with respect to the previous component. More octave components enable to 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 is"320x240"๐.rate,rโ specify the frame rate expected for the video stream, expressed as a number of frames per second. Default value is25โฑ๏ธ.octavesโ specify the total number of components making up the noise, each one with doubled frequency. Default value is1๐ถ.persistenceโ set the ratio used to compute the amplitude of the next octave component with respect to the previous component amplitude. Default value is1๐.xscale,yscaleโ define a scale factor used to multiple thex,ycoordinates. This can be useful to define an effect with a pattern stretched along thexoryaxis. Default value is1๐.tscaleโ define a scale factor used to multiple the time coordinate. This can be useful to change the time variation speed. Default value is1๐ฐ๏ธ.random_modeโ set random mode used to compute initial pattern ๐ฒ.
Supported values are:
randomโ compute and use random seed ๐.kenโ use the predefined initial pattern defined by Ken Perlin in the original article, can be useful to compare the output with other sources ๐.seedโ use the value specified byrandom_seedoption ๐ฑ.
Default value is "random" โจ.
random_seed,seedโ whenrandom_modeis set torandom_seed, use this value to compute the initial pattern. Default value is0๐ข.
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
yaxis, and convert gray level to red-only signal:
perlin=octaves=7:tscale=0.4:yscale=0.3,lutrgb=r=val:b=0:g=0
๐ณ qrencodesrc
Generates a QR code using the libqrencode library (see <https://fukuchi.org/works/qrencode/>) ๐ฑโจ.
To enable the compilation of this source, you need to configure FFmpeg with --enable-libqrencode ๐ ๏ธ.
The QR code is generated from the provided text or text pattern ๐. The corresponding QR code is scaled and put in the video output according to the specified output size options ๐.
In case no text is specified, the QR code is not generated, but an empty colored output is returned instead ๐.
This source 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 ๐. 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 ๐ซถ.
These expressions are evaluated only once, when initializing the source ๐ . See the qrencode Expressions section for details ๐.
okay so quick heads-up bestie: some of the constants are lowkey missing for the source (like x or t or ยธn), because they only make sense when youโre evaluating the expression for each frame instead of at initialization time. no cap, thatโs just the vibe ๐
rate,rโ sets the frame rate of the sourced video, aka how many frames get generated per second. it has to 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"โจcase_sensitive,csโ tellslibqrencodeto use case sensitive encoding. this is enabled by default. you can disable it to reduce the QR encoding size ๐level,lโ sets 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. can be either"none"or"normal"(default). see the qrencode Text expansion section for the details ๐ฆtexttextfileโ define the text to be rendered. if neither is specified, no QR is encoded (just an empty colored frame, iconic but empty ๐). if expansion is enabled, the text is treated as a text template using the qrencode expansion mechanism. see the qrencode Text expansion section for details.background_color,bcforeground_color,fcโ set the QR code and background color. default forforeground_coloris"black", default forbackground_coloris"white". for the syntax of the color options, check the"Color"section in theffmpeg-utilsmanual ๐
๐ 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}
๐ allrgb, allyuv, color, colorchart, colorspectrum, haldclutsrc, nullsrc, pal75bars, pal100bars, rgbtestsrc, smptebars, smptehdbars, testsrc, testsrc2, yuvtestsrc
okay so this is the source squad, and they all have main character energy in different ways ๐
the "allrgb" source returns frames of size 4096x4096 of all rgb colors. literally all of them.
the "allyuv" source returns frames of size 4096x4096 of all yuv colors. yuv girlies rise ๐ซถ
the "color" source provides an uniformly colored input. simple, clean, slay.
the "colorchart" source provides a colors checker chart ๐จ
the "colorspectrum" source provides a color spectrum input ๐
the "haldclutsrc" source provides an identity Hald CLUT. see also haldclut filter.
the "nullsrc" source returns unprocessed video frames. itโs mainly useful in analysis / debugging tools, or as the source for filters which ignore the input data. lowkey the โno thoughts head emptyโ source ๐
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 donโt, thatโs a vibe check fail ๐ญ
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. this is mainly intended for testing purposes.
the "testsrc2" source is similar to testsrc, but supports more pixel formats instead of just "rgb24". this allows using it as an input for other tests without requiring a format conversion. glow-up fr fr โจ
the "yuvtestsrc" source generates an YUV test pattern. you should see a y, cb and cr stripe from top to bottom.
the sources accept the following parameters:
levelโ sets the level of the Hald CLUT, only available in the"haldclutsrc"source. 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 sets the color of the source, only available in the"color"source. for the syntax of this option, check the"Color"section in theffmpeg-utilsmanual.size,sโ sets the size of the sourced video. for the syntax of this option, check the"Video size"section in theffmpeg-utilsmanual. default value is"320x240". this option is not available with the"allrgb","allyuv", and"haldclutsrc"filters ๐ซrate,rโ sets 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. default value is"25".duration,dโ sets the duration of the sourced video. see the Time duration section in theffmpeg-utils(1)manual for the accepted syntax. if not specified, or if the expressed duration is negative, the video is supposed to be generated forever โพ๏ธ. since the frame rate is used as time base, all frames including the last one will have their full duration. if the specified duration is not a multiple of the frame duration, it will be rounded up.sarโ sets the sample aspect ratio of the sourced video.alphaโ sets the alpha (opacity) of the background, only available in the"testsrc2"source. the value must be between0(fully transparent) and255(fully opaque, the default).decimals,nโ sets the number of decimals to show in the timestamp, only available in the"testsrc"source. 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 the"colorspectrum"source. can be one of the following:blackwhiteall
patch_sizeโ sets patch size of single color patch, only available in the"colorchart"source. default is"64x64".presetโ sets colorchecker colors preset, only available in the"colorchart"source. available values are:referenceskintones
default value is "reference".
๐ธ 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
"qcif"and 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,
"nullsrc"can be used. the following command generates noise in the luma plane by employing the"geq"filter:
nullsrc=s=256x256, geq=random(1)*255:128:128
๐ Commands
the "color" source supports the following commands:
c,colorโ sets the color of the created image. accepts the same syntax of the corresponding color option.
๐ฆ openclsrc
generate video using an OpenCL program. nerdy but make it fashion ๐
sourceโ OpenCL program source file.kernelโ kernel name in program.size,sโ size of frames to generate. this must be set.formatโ pixel format to use for the generated frames. this must be set.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.) ๐
__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. iconic fractal behavior โจ
__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);
}
โญ sierpinski
generates a Sierpinski carpet/triangle fractal, and randomly pans around. art but make it math ๐จ
this source accepts the following options:
size,sโ sets frame size. for the syntax of this option, check the"Video size"section in theffmpeg-utilsmanual. default value is"640x480".rate,rโ sets frame rate, expressed as number of frames per second. default value is"25".seedโ sets seed which is used for random panning.jumpโ sets max jump for single pan destination. allowed range is from1to10000.typeโ sets fractal type, can be default"carpet"or"triangle".
๐ zoneplate
generates a zoneplate test video pattern. very test, very video, very zoneplate ๐
this source accepts the following options:
size,sโ sets frame size. for the syntax of this option, check the"Video size"section in theffmpeg-utilsmanual. default value is"320x240".rate,rโ sets the frame rate, i.e. how many frames per second. the default is"25"โญduration,dโ how long the sourced video lasts. the accepted syntax is in the Time duration section of theffmpeg-utils(1)manual, iykyk. and if you don't specify it โ or the duration you give is negative โ the video is supposed to be generated forever ๐ญ๐sarโ sets the sample aspect ratio of the sourced video. cute, simple.precisionโ sets the precision in bits for the look-up table used for sine calculations. default is10, allowed range is4to16โจxoโ horizontal axis offset for the output signal. default0.yoโ vertical axis offset for the output signal. default0.toโ time axis offset for the output signal. default0.k0โ the 0-order constant added to the signal phase. default0.kxโ the 1-order phase factor multiplier for the horizontal axis. default0.kyโ the 1-order phase factor multiplier for the vertical axis. default0.ktโ the 1-order phase factor multiplier for the time axis. default0.kxt,kyt,kxyโ phase factor multipliers for the combination of spatial and temporal axis. default0.kx2โ the 2-order phase factor multiplier for the horizontal axis. default0.ky2โ the 2-order phase factor multiplier for the vertical axis. default0.kt2โ the 2-order phase factor multiplier for the time axis. default0.kuโ the constant added to the final phase to produce the chroma-blue component of the signal. default0๐kvโ the constant added to the final phase to produce the chroma-red component of the signal. default0โค๏ธ
๐ฎ Commands
this source also supports some of the options above as commands. periodt.
โจ Examples
- generate a horizontal color sine sweep:
zoneplate=ku=512:kv=0:kt2=0:kx2=256:s=wvga:xo=-426:kt=11
- generate a vertical color sine sweep:
zoneplate=ku=512:kv=0:kt2=0:ky2=156:s=wvga:yo=-240:kt=11
- generate a circular zone-plate:
zoneplate=ku=512:kv=100:kt2=0:ky2=256:kx2=556:s=wvga:yo=0:kt=11
๐ฌ VIDEO SINKS
okay bestie, here's the rundown on the currently available video sinks. the end-of-the-pipeline girlies ๐ซถ
buffersink
buffers video frames and makes them available to the end of the filter graph. it's giving "the final boss of the graph".
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 AVBufferSinkContext structure โ that's the thing that defines the incoming buffers' formats โ which gets passed as the opaque parameter to "avfilter_init_filter" for initialization. no cap.
nullsink
null video sink: does absolutely nothing with the input video ๐ it's mainly useful as a template, and for use in analysis / debugging tools. it's the "i'm just here to vibe" of sinks.
๐ MULTIMEDIA FILTERS
below is the description of the currently available multimedia filters. these ones do the most, fr fr ๐
a3dscope
converts input audio to 3d scope video output. it's giving audio but make it cinematic ๐
the filter accepts the following options:
rate,rโ sets the frame rate, expressed as number of frames per second. default value is"25".size,sโ specifies the video size for the output. for the syntax of this option, check the Video size section in theffmpeg-utilsmanual. default value is"hd720"โจfovโ sets the camera field of view. default is90degrees. allowed range is from40to150.rollโ sets the camera roll.pitchโ sets the camera pitch.yawโ sets the camera yaw.xzoomโ sets the camera zoom on the X-axis.yzoomโ sets the camera zoom on the Y-axis.zzoomโ sets the camera zoom on the Z-axis.xposโ sets the camera position on the X-axis.yposโ sets the camera position on the Y-axis.zposโ sets the camera position on the Z-axis.lengthโ sets the length of displayed audio waves in number of frames.
๐ฎ Commands
the filter supports some of the options above as commands. slay.
abitscope
converts input audio to a video output, displaying the audio bit scope. little visual of your bits, basically ๐
the filter accepts the following options:
rate,rโ sets the frame rate, expressed as number of frames per second. default value is"25".size,sโ specifies the video size for the output. for the syntax of this option, check the Video size section in theffmpeg-utilsmanual. default value is"1024x256".colorsโ specify a list of colors separated by a space or by'|', which will be used to draw the channels. unrecognized or missing colors get replaced by white. so if your color choices are a mystery, congrats, it's white now ๐mode,mโ sets the output mode. can be"bars"or"trace". default is"bars".
adrawgraph
draws a graph using input audio metadata. โ๏ธ See drawgraph.
agraphmonitor
See graphmonitor. that's it, that's the whole vibe check โจ
ahistogram
converts input audio to a video output, displaying the volume histogram. it's the "look at my range" filter ๐
the filter accepts the following options:
dmodeโ specifies how the histogram is calculated. it accepts the following values:singleโ use a single histogram for all channels.separateโ use a separate histogram for each channel.
default is "single".
rate,rโ sets the frame rate, expressed as number of frames per second. default value is"25".size,sโ specifies the video size for the output. for the syntax of this option, check the Video size section in theffmpeg-utilsmanual. default value is"hd720".scaleโ sets the display scale. it accepts the following values:logโ logarithmicsqrtโ square rootcbrtโ cubic rootlinโ linearrlogโ reverse logarithmic
default is "log".
ascaleโ sets the amplitude scale. it accepts the following values:logโ logarithmiclinโ linear
default is "log".
acountโ sets how many frames to accumulate in the histogram. default is1. setting this to-1accumulates all frames ๐คrheightโ sets the histogram ratio of window height.slideโ sets the sonogram sliding. it accepts the following values:replaceโ replace old rows with new ones.scrollโ scroll from top to bottom.
default is "replace".
hmodeโ sets the histogram mode. it accepts the following values:absโ use absolute values of samples.signโ use untouched values of samples.
default is "abs".
aphasemeter
measures the phase of the input audio, which gets exported as metadata "lavfi.aphasemeter.phase" โ that's 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. main character behavior: shows up, does its job, leaves your audio intact ๐ซถ
audio will be rematrixed to stereo if it has a different channel layout. the phase value is in range "[-1, 1]", where -1 means the left and right channels are completely out of phase, and 1 means the channels are in phase. no in-between erasure ๐
the filter accepts the following options, all related to its video output:
rate,rโ sets the output frame rate. default value is25.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 is"800x400".rc,gc,bcโ specify the red, green, blue contrast. default values are2,7and1. allowed range is"[0, 255]".mpcโ sets the color used for drawing the median phase. if the color is"none", which is the default, no median phase value will be drawn.videoโ enables video output. default is enabled.
๐ phasing detection
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. it's literally the group chat notifying you that something's off ๐ญ
the filter accepts the following options for this detection:
phasingโ enables mono and out of phase detection. default is disabled.tolerance,tโ sets the phase tolerance for mono detection, in amplitude ratio. default is0. allowed range is"[0, 1]".angle,aโ sets the angle threshold for out of phase detection, in degree. default is170. allowed range is"[90, 180]".duration,dโ sets the mono or out of phase duration until notification, expressed in seconds. default is2.
โจ Examples
- 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 -
avectorscope
converts input audio to a video output, representing the audio vector scope. ๐ฆ
the filter is used to measure the difference between channels of a stereo audio stream. a monaural signal โ identical left and right signal โ results in a straight vertical line. any stereo separation is visible as a deviation from this line, creating a Lissajous figure. and if that straight line (or a deviation from it) shows up but horizontal, that indicates the left and right channels are out of phase. so like, the vibe check is entirely geometric ๐
the filter accepts the following options:
mode,mโ sets 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 sets the video size for the output. for the syntax of this option, check the Video size section in theffmpeg-utilsmanual. default value is"400x400".rate,rโ sets the output frame rate. default value is25.rc,gc,bc,acโ specify the red, green, blue and alpha contrast. default values are40,160,80and255. allowed range is"[0, 255]".rf,gf,bf,afโ specify the red, green, blue and alpha fade. default values are15,10,5and5. allowed range is"[0, 255]".zoomโ sets the zoom factor. default value is1. allowed range is"[0, 10]". values lower than1will auto adjust the zoom factor to the maximal possible value. it's giving "i'll fix it for you bestie" ๐ซถdrawโ sets 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 specifies the amplitude scale of audio samples. available values are:linโ linear.sqrtโ square root.cbrtโ cubic root.logโ logarithmic.
swapโ swaps the left channel axis with the right channel axis.mirrorโ mirrors the axis.noneโ no mirror.
xโ mirror only the x axis ๐ชyโ mirror only the y axis ๐ชxyโ mirror both axes, go off king ๐
๐ธ Examples
- Complete example using
ffplayโ yes bestie, this is the whole thing, run it and watch the pretty circles:
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
This filter supports all the options above as commands โ every single one โ except size and rate. Those two are built different and don't take orders mid-stream, sorry. ๐
โฑ๏ธ bench, abench
Lowkey a stopwatch for your filtergraph. It benchmarks part of a filtergraph, no cap.
The filter accepts the following options:
actionโ start or stop a timer. That's the whole vibe check.
Available values are:
startโ grab the current time, stash it as frame metadata (using the keylavfi.bench.start_time), and forward that frame on to the next filter. ๐ซถstopโ grab the current time and fetch thelavfi.bench.start_timemetadata off the input frame's metadata to work out the time difference. Then it prints the time difference, average, maximum and minimum time (respectivelyt,avg,maxandmin). The timestamps are expressed in seconds. โฒ๏ธ
โจ Examples
- Benchmark the
selectivecolorfilter โ wrap it in a bench sandwich, iconic:
bench=start,selectivecolor=reds=-.2 .12 -.49,bench=stop
๐ concat
Concatenate audio and video streams, joining them together one after the other. It's giving "playlist but make it filters." ๐ถ
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. No mixing and matching, bestie โ keep it consistent. โจ
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. โ ๏ธ (it's called unsafe for a reason, bestie, proceed with caution)
The filter has v+a outputs: first v video outputs, then a audio outputs. ๐บ๐
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, always. 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 (silence is golden, and also a padding strategy)
For this filter to work correctly, all segments must start at timestamp 0. Not 0.1, not "roughly zero" โ zero. ๐ฏ
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. That part's on you, bestie. ๐ซก
Different frame rates are acceptable but will result in variable frame rate at output; be sure to configure the output file to handle it. It's giving chaos but the manageable kind. ๐
๐ Examples
- Concatenate an opening, an episode and an ending, all in bilingual version (video in stream
0, audio in streams1and2) โ the full trilogy arc, obsessed:
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)movie sources, and adjusting the resolution โ multitasking queen behavior:
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]
Heads up bestie: a desync will happen at the stitch if the audio and video streams do not have exactly the same duration in the first file. Not a maybe. A will. ๐ญ
๐ Commands
This filter supports the following commands:
nextโ close the current segment and step to the next one. On to the next era, periodt. โจ
๐ ebur128
EBU R128 scanner filter. It takes an audio stream and analyzes its loudness level โ like a vibe check but for volume. 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). ๐
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. Don't forget your conversion bestie, or you'll get something sus at the end. ๐
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). ๐
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 the "Video size" section in theffmpeg-utilsmanual. Default and minimum resolution is640x480. ๐meterโ 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. Pick your fighter. ๐ฅmetadataโ 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 is0. ๐ท๏ธframelogโ force the frame logging level.
Available values are:
quietโ logging disabled ๐คinfoโ information logging levelverboseโ verbose logging level ๐ฃ๏ธ
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 bySPK). ๐trueโ 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 byTPK) and true-peak per frame (identified byFTPK). This mode requires a build withlibswresample. โ ๏ธ
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. ๐งpanlawโ 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 (inLUFS) 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). ๐๏ธgaugeโ set the value displayed by the gauge. Valid values aremomentaryand sshortterm. 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). ๐๏ธscaleโ sets the display scale for the loudness. Valid parameters areabsolute(inLUFS) 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, inLUFS. ๐rangeโ read-only exported value for measured loudness range, inLU. ๐lra_lowโ read-only exported value for measured LRA low, inLUFS. ๐lra_highโ read-only exported value for measured LRA high, inLUFS. ๐sample_peakโ read-only exported value for measured sample peak, indBFS. ๐true_peakโ read-only exported value for measured true peak, indBFS. ๐
๐ฆ Examples
- Real-time graph using
ffplay, with a EBU scale meter +18 โ visually stunning, honestly:
ffplay -f lavfi -i "amovie=input.mp3,ebur128=video=1:meter=18 [out0][out1]"
- Run an analysis with
ffmpegโ the no-notes version:
ffmpeg -nostats -i input.mp3 -filter_complex ebur128 -f null -
๐งต interleave, ainterleave
Temporally interleave frames from several inputs. Take turns bestie, we're sharing. ๐ค
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 allowed. โฐ
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. Not me waiting forever for one input to text back. 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. That's the whole mood.
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. Fair's fair. ๐
These filters accept the following options:
nb_inputs,nโ set the number of different inputs, it is2by default. ๐ฏdurationโ how to determine the end-of-stream.longestโ the duration of the longest input. (default) ๐ขshortestโ the duration of the shortest input. ๐
firstโ how long the first input is ๐ซ
Examples โจ
- Interleave frames that belong to different streams, using
ffmpeg:
ffmpeg -i bambi.avi -i pr0n.mkv -filter_complex "[0:v][1:v] interleave" out.avi
- Add a flickering blur effect, bestie:
select='if(gt(random(0), 0.2), 1, 2)':n=2 [tmp], boxblur=2:2, [tmp] interleave
latency, alatency โฑ๏ธ
Measures how much latency the filtering has, okay? ๐ซถ
It reports the previous filter's filtering latency โ the delay in number of audio samples for audio filters, or number of video frames for video filters.
When the input stream ends, the filter reports the min and max measured latency for the previously running filter in the filtergraph. cute, right? ๐
metadata, ametadata ๐ท๏ธ
Manipulates frame metadata. Obsessed, honestly.
This filter accepts the following options:
modeโ sets the mode of operation of the filter ๐ธ
Can be one of the following:
selectโ if bothvalueandkeyare set, it selects frames that have such metadata. If onlykeyis set, it selects every frame that has that key in its metadata.addโ adds new metadatakeyandvalue. If the key is already there, it does nothing.modifyโ modifies the value of a key that's already present.deleteโ ifvalueis set, it deletes only keys that have such value. Otherwise, it deletes the key. Ifkeyisn't set, it deletes all metadata values in the frame ๐printโ prints the key and its value if metadata was found. Ifkeyisn't set, it prints all metadata values available in the frame.
keyโ sets the key used with all modes. It must be set for all modes exceptprintanddelete.valueโ sets the metadata value that will be used. This option is mandatory formodifyandaddmode ๐functionโ which function to use when comparing metadata value andvalue.
Can be one of 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 optionexprevaluates to true.ends_withโ values are interpreted as strings, returns true if the metadata value ends with thevalueoption string.
exprโ sets the expression used whenfunctionis set toexpr. The expression is evaluated through the eval API and can contain the following 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 is written to the named file. Instead of a plain filename you can specify any writable url. The filename ``-'' is shorthand for standard output. If thefileoption isn't set, output goes to the log withAV_LOG_INFOloglevel.directโ reduces buffering in print mode when output is written to a URL set usingfile.
Examples ๐
- Print all metadata values for frames with the 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'
perms, aperms ๐
Sets read/write permissions for the output frames.
These filters are mainly aimed at developers, to test the direct path in the following filter in the filtergraph. iykyk ๐ง
The filters accept the following options:
modeโ selects the permissions mode.
It accepts the following values:
noneโ does nothing. This is the default.roโ sets all the output frames read-only.rwโ sets all the output frames directly writable.toggleโ makes the frame read-only if writable, and writable if read-only.randomโ sets each output frame read-only or writable randomly.
seedโ sets the seed for therandommode, and must be an integer included 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.
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 ๐ญ Inserting aformatoraformatfilter before theperms/apermsfilter can avoid this problem.
realtime, arealtime โณ
Slows down filtering to match real time approximately.
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 time limit for the pauses. Any pause longer than that gets 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 than1.0will result in faster than realtime processing, smaller values will slow processing down. The limit is automatically adapted accordingly. Default is1.0.
A processing speed faster than what's possible without these filters cannot be achieved. no cap ๐ซถ
Commands ๐
Both filters support all the above options as commands.
segment, asegment โ๏ธ
Splits a single input stream into multiple streams.
This filter does the opposite of the concat filters.
segment works on video frames, asegment on audio samples.
This filter accepts the following options:
timestampsโ timestamps of 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.frames,samplesโ exact frame/sample count to split the segments.
In all cases, prefixing each segment with '+' makes it relative to the previous segment โจ
Examples ๐ฆ
- Split the input audio stream into three output audio streams: 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"
select, aselect ๐
Selects frames to pass in the output.
This filter accepts the following options:
expr,eโ sets the expression, which is evaluated for each input frame.
If the expression evaluates to zero, the frame is discarded.
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 ๐
outputs,nโ sets the number of outputs. The output to which the selected frame gets sent 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 from 0.selected_nโ the (sequential) number of the selected frame, starting from 0.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 isn'tNAN. It remainsNANif not found.start_tโ the first PTS, in seconds, in the stream which isn'tNAN. It remainsNANif not found.pict_type(video only) โ the type of the filtered frame. It can assume one of the following values:IPBSSISPBI
interlace_type(video only) โ the frame interlace type. It can assume one of the following 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.posโ the position in the file of the filtered frame,-1if the information isn't available (e.g. for synthetic video); deprecated, do not use ๐ฉscene(video only) โ value between 0 and 1 to 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).concatdec_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 aren't 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. ๐
Okay so the concatdec_select variable is -1 when the frame pts is at least start_time and either the duration metadata is missing or the frame pts is less than start_time + duration, itโs 0 otherwise, and itโs NaN if the start_time metadata is missing.
That basically means an input frame gets selected if its pts is inside the interval set by the concat demuxer. Bestie, thatโs the whole vibe check. ๐ฆ
iw(video only) โ the width of the input video frame.ih(video only) โ the height of the input video frame.view(video only) โ View ID for multi-view video.
The default value of the select expression is "1".
โจ Examples โจ
- Select all frames in input:
select
The example above is the same as:
select=1
- Skip all frames:
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
Comparing scene against a value between 0.3 and 0.5 is generally a sane choice.
- 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
ffconcatfile 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.
These filters read commands that get sent to other filters in the filtergraph.
sendcmd has to be inserted between two video filters, and asendcmd has to be inserted between two audio filters โ but apart from that, they act the same way. Periodt. ๐
You can provide the command specification 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.filename,fโ set the filename of the commands to be read and sent to the other filters.
Commands syntax
A commands description is a sequence of interval specifications, and it includes a list of commands to execute when a particular event related to that interval happens. The event is typically the current frame time entering or leaving a given time interval. ๐
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.
The current frame time counts as within the specified interval if itโs included in the interval [START, END) โ that is, when the time is greater than or equal to START and lesser than END.
COMMANDS is a sequence of one or more command specifications, separated by ,, relating to that interval. The syntax of a command specification is:
[<FLAGS>] <TARGET> <COMMAND> <ARG>
FLAGS is optional and specifies the type of events relating to the time interval that enable sending the specified command. It must be a non-null sequence of identifier flags separated by + or | and enclosed between [ and ]. โจ
The following flags are recognized:
enterโ the command is sent when the current frame timestamp enters the specified interval. In other words, itโs sent when the previous frame timestamp was not in the given interval, and the current one is.leaveโ the command is sent when the current frame timestamp leaves the specified interval. In other words, itโs sent when the previous frame timestamp was in the given interval, and the current one is not.exprโ the commandARGis interpreted as an expression and the result of the expression is passed asARG.
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.PTSโ 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 is not specified, a default value of [enter] is assumed.
TARGET specifies the target of the command, usually the name of the filter class or a specific filter instance name.
COMMAND specifies the name of the command for the target filter.
ARG is optional and specifies the optional list of arguments for the given COMMAND.
Between one interval specification and another, whitespaces, or sequences of characters starting with # until the end of line, are ignored and can be used to annotate comments.
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>]
Examples
- 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 lets you 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
โฑ๏ธ setpts, asetpts โฑ๏ธ
Change the PTS (presentation timestamp) of the input frames.
setpts works on video frames, and asetpts works on audio frames. Slay, but make it timestamps. ๐
This filter accepts the following options:
exprโ the expression evaluated for each frame to construct its timestamp.strip_fps(video only) โ a boolean option that determines if the original framerate and frame duration metadata is unset. If set to true, be advised that a sane frame rate should be explicitly specified if output is sent to a constant frame rate muxer. Default is"false".
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.PREV_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.
Examples
- 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
Commands
Both filters support all above options as commands. Iconic. ๐
๐ setrange ๐
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, but only sets the corresponding property, which affects how the frame is treated by following filters.
The filter accepts the following options:
range
okay so this one's a lil picker for the color range ๐ here's what you can hand it:
autoโ keeps the exact same color range property it already had. no notes, it just vibes.unspecified,unknownโ marks the color range as unspecified.limited,tv,mpegโ sets the color range to limited.full,pc,jpegโ sets the color range to full.
โจ settb, asettb โจ
This one sets the timebase used for the output frames' timestamps. Honestly? It's mostly here for testing timebase config โ like a little lab rat for your timestamps ๐งช
It takes these parameters:
expr,tbโ the expression that gets evaluated into the output timebase.
So the value you give for tb is an arithmetic expression that represents a rational number. That expression can use the constants "AVTB" (the default timebase, bestie ๐), "intb" (the input timebase) and "sr" (the sample rate โ audio only, ikyk). The default value is "intb".
๐ธ 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
This is the iconic one, no cap ๐ โ it 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 manpage itself is here to humble it: the transform itself is not really constant Q โ the Q factor is actually variable/clamped ๐. It comes with a musical tone scale, from E0 to D#10.
The filter accepts these options:
size,sโ specifies 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 is1920x1080.fps,rate,rโ sets the output frame rate. Default value is25.bar_hโ sets the bargraph height. It must be even. Default value is-1, which computes the bargraph height automatically โจaxis_hโ sets the axis height. It must be even. Default value is-1, which computes the axis height automatically.sono_hโ sets the sonogram height. It must be even. Default value is-1, which computes the sonogram height automatically.fullhdโ sets the fullhd resolution. โ ๏ธ This option is deprecated, usesize,sinstead. Default value is1.sono_v,volumeโ specifies the sonogram volume expression. It can contain these variables:bar_vโ thebar_vevaluated expressionfrequency,freq,fโ the frequency where it is evaluatedtimeclamp,tcโ the value of thetimeclampoption
and these functions:
a_weighting(f)โ A-weighting of equal loudnessb_weighting(f)โ B-weighting of equal loudnessc_weighting(f)โ C-weighting of equal loudness
Default value is 16.
bar_v,volume2โ specifies the bargraph volume expression. It can contain these variables:sono_vโ thesono_vevaluated expressionfrequency,freq,fโ the frequency where it is evaluatedtimeclamp,tcโ the value of thetimeclampoption
and these functions:
a_weighting(f)โ A-weighting of equal loudnessb_weighting(f)โ B-weighting of equal loudnessc_weighting(f)โ C-weighting of equal loudness
Default value is "sono_v".
sono_g,gammaโ specifies the sonogram gamma. Lower gamma = more contrast in the spectrum, higher gamma = the spectrum gets more range. Default value is3. Acceptable range is[1, 7].bar_g,gamma2โ specifies the bargraph gamma. Default value is1. Acceptable range is[1, 7].bar_tโ specifies the bargraph transparency level. Lower value makes the bargraph sharper. Default value is1. Acceptable range is[0, 1].timeclamp,tcโ specifies the transform timeclamp. At low frequency there's a trade-off between accuracy in the time domain vs the frequency domain ๐ซถ Iftimeclampis lower, events in the time domain get represented more accurately (think a fast bass drum); otherwise events in the frequency domain get represented more accurately (think a bass guitar). Acceptable range is[0.002, 1]. Default value is0.17.attackโ sets the attack time in seconds. The default is0(disabled). Otherwise it limits future samples by applying asymmetric windowing in the time domain โ super useful when you need low latency โก Accepted range is[0, 1].basefreqโ specifies the transform base frequency. Default value is20.01523126408007475, which is the frequency 50 cents below E0. Acceptable range is[10, 100000].endfreqโ specifies the transform end frequency. Default value is20495.59681441799654, which is the frequency 50 cents above D#10. Acceptable range is[10, 100000].coeffclampโ โ ๏ธ this option is deprecated and ignored. it's just sitting there. leave it alone ๐tlengthโ specifies the transform length in the time domain. Use this 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 evaluatedtimeclamp,tcโ the value of thetimeclampoption
Default value is "384*tc/(384+tc*f)".
countโ specifies the transform count for every video frame. Default value is6. Acceptable range is[1, 30].fcountโ specifies the transform count for every single pixel. Default value is0, which makes it computed automatically. Acceptable range is[0, 10].fontfileโ specifies the font file for use with freetype to draw the axis. If it's not specified, it uses the embedded font. ๐ Note that drawing with a font file or the embedded font is not implemented with custombasefreqandendfreqโ use theaxisfileoption instead.fontโ specifies a fontconfig pattern. This has lower priority thanfontfile. The":"in the pattern may be replaced by"|"to avoid unnecessary escaping.fontcolorโ specifies the font color expression. This is an arithmetic expression that should return an integer value0xRRGGBB. It can contain these variables:frequency,freq,fโ the frequency where it is evaluatedtimeclamp,tcโ the value of thetimeclampoption
and these functions:
midi(f)โ midi number of frequencyf. Some midi numbers for you: E0(16), C1(24), C2(36), A4(69) ๐นr(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 specifies an image file to draw the axis. This option overrides thefontfileandfontcoloroptions ๐ฅaxis,textโ enable/disable drawing text to the axis. If it's set to0, drawing to the axis is disabled, ignoring thefontfileandaxisfileoptions. Default value is1.cspโ set colorspace. Accepted values are:unspecifiedโ Unspecified (default)bt709โ BT.709fccโ FCCbt470bgโ BT.470BG or BT.601-6 625smpte170mโ SMPTE-170M or BT.601-6 525smpte240mโ SMPTE-240Mbt2020nclโ BT.2020 with non-constant luminance
cschemeโ sets the spectrogram color scheme. This is a list of floating point values with the format"left_r|left_g|left_b|right_r|right_g|right_b". The default is"1|0.5|0|0|0.5|1".
๐ 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 tlength equation:
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 fontcolor and fontfile, 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
๐ฆ showcwt ๐ฆ
Converts input audio into a video output that represents the frequency spectrum using a Continuous Wavelet Transform and Morlet wavelet ๐ cute AND mathy.
The filter accepts these options:
size,sโ specifies the video size for the output. For the syntax of this option, check the "Video size" section in theffmpeg-utilsmanual. Default value is640x512.rate,rโ sets the output frame rate. Default value is25.scaleโ sets the frequency scale used. Allowed values are:linearlogbarkmelerbssqrtcbrtqdrtfm
Default value is "linear".
iscaleโ sets the intensity scale used. Allowed values are:linearlogsqrtcbrtqdrt
Default value is "log".
minโ sets the minimum frequency that will be used in output. Default is20Hz.maxโ sets the maximum frequency that will be used in output. Default is20000Hz. Heads up bestie: the real frequency upper limit depends on the input audio's sample rate, and that limit will be enforced on this value when it's set to something greater than the Nyquist frequency ๐จiminโ sets the minimum intensity that will be used in output.imaxโ sets the maximum intensity that will be used in output.logbโ sets the logarithmic basis for how brightness strength gets mapped when we translate calculated magnitude values into pixel values, bestie. Allowed range is0to1. Default value is0.0001. ๐deviationโ sets the frequency deviation. Values lower than1are more frequency oriented, values higher than1are more time oriented (iykyk). Allowed range is0to10. Default value is1.ppsโ sets the number of pixel output per each second in one row. Allowed range is from1to1024. Default value is64.modeโ sets the output visual mode. Allowed values are:magnitudeโ show magnitude. โจphaseโ show only phase.magphaseโ show combination of magnitude and phase. Magnitude is mapped to brightness and phase to color. Iconic tbh.channelโ show unique color per channel magnitude.stereoโ show unique color per stereo difference.
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.rlโ direction from right to left.udโ direction from up to down.duโ direction from down to up.
barโ sets the ratio of bargraph display to display size. Default is0.rotationโ sets color rotation, must be in[-1.0, 1.0]range. Default value is0.
๐ showfreqs ๐
Converts input audio to video output representing the audio power spectrum. Audio amplitude is on the Y-axis while frequency is on the X-axis. It's giving science fair but make it cute ๐ง
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".rate,rโ set video rate. Default is25.modeโ 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.sqrtโ square root scale.cbrtโ cubic root scale.logโ logarithmic scale.
Default is "log".
fscaleโ set frequency scale.
It accepts the following values:
linโ linear scale.logโ logarithmic scale.rlogโ reverse logarithmic scale.
Default is "lin".
win_sizeโ set window size. Allowed range is from16to65536.
Default is 2048
win_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".
overlapโ set window overlap. In range[0, 1]. Default is1, which means optimal overlap for the selected window function will be picked. She picks for you, queen ๐averagingโ set time averaging. Setting this to0will display current maximal peaks. Default is1, which means time averaging is disabled.colorsโ 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. Rude but okay ๐cmodeโ set channel display mode.
It accepts the following values:
combinedseparate
Default is "combined".
minampโ set minimum amplitude used in"log"amplitude scaler.dataโ 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.
๐ฆ showspatial ๐ฆ
Converts stereo input audio to a video output, representing the spatial relationship between two channels. Just the two of them, main character energy fr fr.
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".win_sizeโ set window size. Allowed range is from1024to65536. Default size is4096.win_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".
rate,rโ set output framerate.
๐ showspectrum ๐
Converts input audio to a video output, representing the audio frequency spectrum. Obsessed with her, no cap 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".slideโ 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 rightscrollโ the samples scroll from right to leftfullframeโ frames are only produced when the samples reach the rightrscrollโ the samples scroll from left to rightlreplaceโ the samples start again on the right when they reach the left
Default value is "replace".
modeโ specify display mode.
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.
colorโ specify 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 scheme ๐morelandโ 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 scheme ๐ฅfieryโ each channel is displayed using the fiery color schemefruitโ each channel is displayed using the fruit color scheme ๐coolโ 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 channel.
scaleโ specify 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 sqrt.
fscaleโ specify frequency scale.
It accepts the following values:
linโ linearlogโ logarithmic
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 is1.win_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".
orientationโ set orientation of time vs frequency axis. Can be"vertical"or"horizontal". Default is"vertical".overlapโ set ratio of overlap window. Default value is0. When value is1overlap is set to recommended size for specific window function currently used.gainโ set scale gain for calculating intensity color values. Default value is1.dataโ set which data to display. Can be"magnitude", default, or"phase", or unwrapped phase:"uphase".rotationโ set color rotation, must be in[-1.0, 1.0]range. Default value is0.startโ set start frequency from which to display spectrogram. Default is0.stopโ set stop frequency to which to display spectrogram. Default is0.fpsโ set upper frame rate limit. Default is"auto", unlimited.legendโ draw time and frequency axes and legends. Default is disabled.drangeโ set dynamic range used to calculate intensity color values. Default is120dBFS. Allowed range is from10to200.limitโ set upper limit of input audio samples volume in dBFS. Default is0dBFS. Allowed range is from-100to100.opacityโ set opacity strength when using pixel format output with alpha component.
The usage is very similar to the showwaves filter; see the examples in that section.
๐ธ Examples ๐ธ
- 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 to a single video frame, representing the audio frequency spectrum. One frame, one moment, immaculate vibes โจ
The filter accepts the following options:
size,sโ sets the video size for the output ๐ for the syntax of this one, peep the "Video size" section in theffmpeg-utilsmanual. Default is4096x2048(yes, big girl size).modeโ the display mode, bestie. Here's what it takes:combinedโ all channels displayed in the same rowseparateโ all channels displayed in separate rows
Default is combined.
colorโ picks the display color mode. The options are genuinely giving a whole palette:channelโ each channel gets its own separate colorintensityโ each channel uses the same color schemerainbowโ rainbow color schememorelandโ moreland color schemenebulaeโ nebulae color schemefireโ fire color schemefieryโ fiery color schemefruitโ fruit color schemecoolโ cool color schememagmaโ magma color schemegreenโ green color schemeviridisโ viridis color schemeplasmaโ plasma color schemecividisโ cividis color schemeterrainโ terrain color scheme
Default is intensity.
scaleโ the scale used for calculating intensity color values. takes:linโ linearsqrtโ square root, defaultcbrtโ cubic rootlogโ logarithmic4thrtโ 4th root5thrtโ 5th root
Default is log. (yeah the page says both, that's literally what it says, don't come for me ๐ซถ)
fscaleโ sets the frequency scale. takes:linโ linearlogโ logarithmic
Default is lin.
saturationโ sets the saturation modifier for displayed colors ๐ negative values give you an alternative color scheme,0is no saturation at all. Must be in the[-10.0, 10.0]range. Default is1.win_funcโ sets the window function. The full roster, no skips:rectbartletthannhanninghammingblackmanwelchflattopbharrisbnuttallbhannsinenuttalllanczosgausstukeydolphcauchyparzenpoissonbohmankaiser
Default is hann.
orientationโ sets the orientation of the time vs frequency axis. Can beverticalorhorizontal. Default isvertical.gainโ scale gain for calculating intensity color values. Default is1.legendโ draws time and frequency axes and legends. Enabled by default โจrotationโ sets color rotation, must be in the[-1.0, 1.0]range. Default 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 is120dBFS. Allowed range is from10to200.limitโ sets the upper limit of input audio samples volume in dBFS. Default is0dBFS. Allowed range is from-100to100.opacityโ sets the opacity strength when you're using pixel format output with an alpha component ๐
Examples
- Extract an audio spectrogram of a whole audio track in a
1024x1024picture usingffmpeg:
ffmpeg -i audio.flac -lavfi showspectrumpic=s=1024x1024 spectrogram.png
showvolume ๐
Turns input audio volume into a video output. Iconic behavior honestly.
The filter takes these 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. That expression can use these variables:VOLUMEโ current max volume of channel in dBPEAKโ current peakCHANNELโ current channel number, starting from0
tโ if set, displays channel names. Enabled by default.vโ if set, displays volume values. Enabled by default.oโ sets the orientation, can be horizontal:hor vertical:v, default ish.sโ sets the step size, allowed range is[0, 5]. Default is0, which means step is disabled.pโ sets the background opacity, allowed range is[0, 1]. Default is0.mโ sets the metering mode, can be peak:por rms:r, default isp.dsโ sets the display scale, can be linear:linor log:log, default islin.dmโ in second. If set to> 0., displays a line for the max level in the previous seconds. default is disabled:0.dmcโ the color of the max line. Use when thedmoption is set to> 0. default is:orange
showwaves ๐
Turns input audio into a video output representing the sample waves. So cute.
The filter takes these options:
size,sโ sets the video size for the output. For the syntax, check the "Video size" section in theffmpeg-utilsmanual. Default is600x240.modeโ sets the display mode. Available values:pointโ draw a point for each samplelineโ draw a vertical line for each samplep2pโ draw a point for each sample and a line between themclineโ draw a centered vertical line for each sample
Default 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 thenoption. Default is25.split_channelsโ sets if channels should be drawn separately or overlap. Default is0.colorsโ sets colors separated by'|'which are going to be used for drawing of each channel.scaleโ sets the amplitude scale. Available values:linโ linearlogโ logarithmicsqrtโ square rootcbrtโ cubic root
Default is linear.
drawโ sets the draw mode. This is mostly useful to set for highn. Available values:scaleโ scale pixel values for each drawn samplefullโ draw every sample directly
Default is scale.
Examples
- 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 ๐ฆ
Turns input audio into a single video frame, representing the sample waves. One frame, all the vibes.
The filter takes these options:
size,sโ sets the video size for the output. For the syntax, check the "Video size" section in theffmpeg-utilsmanual. Default is600x240.split_channelsโ sets if channels should be drawn separately or overlap. Default is0.colorsโ sets colors separated by'|'which are going to be used for drawing of each channel.scaleโ sets the amplitude scale. Available values:linโ linearlogโ logarithmicsqrtโ square rootcbrtโ cubic root
Default is linear.
drawโ sets the draw mode. Available values:scaleโ scale pixel values for each drawn samplefullโ draw every sample directly
Default is scale.
filterโ sets the filter mode. Available values:averageโ use average samples values for each drawn samplepeakโ use peak samples values for each drawn sample
Default is average.
Examples
- 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 ๐
Deletes frame side data, or selects frames based on it. Chaotic but useful.
This filter takes these options:
modeโ sets the mode of operation of the filter. Can be one of these:selectโ select every frame with side data oftypedeleteโ 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 ๐ 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
spectrumsynth ๐ง
Synthesizes audio from 2 input video spectrums โ the first input stream represents magnitude across time and the 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 reverse-engineering the visual into sound, we love a glow-up ๐
This filter is literally built to reverse processed showspectrum filter outputs โ but bestie, it can also synthesize sound from other spectrograms too. โจ Just know that in that case the results are gonna be poor if the phase data isn't available, because then the phase data has to be recreated, and ngl it's usually just recreated from random noise. ๐ญ
For best results:
- use gray only output (that's
"channel"color mode in theshowspectrumfilter) - use
"log"scale for magnitude video - use
"lin"scale for phase video - to produce phase, for the 2nd video, use the
"data"option - input videos should generally use
"fullframe"slide mode, since that saves the resources needed for decoding video ๐ซถ
The filter accepts the following options:
sample_rateโ set the sample rate of the output audio. Fr fr, the sample rate of the audio the spectrum was generated from may totally differ. ๐channelsโ set how many channels are 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". โญslideโ set the slide that was used when generating the input spectrums. Can be"replace","scroll","fullframe"or"rscroll". Default is"fullframe". ๐win_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. ๐orientationโ set the orientation of the input videos. Can be"vertical"or"horizontal". Default is"vertical".
๐ Examples
- First, create magnitude and phase videos from audio โ this example assumes the audio is stereo with
44100sample rate โ then resynthesize those 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
๐ฆ split, asplit
Split the input into several identical outputs. Iconic behavior, no notes. โจ
"asplit" works with audio input, "split" works with video.
The filter accepts a single parameter which specifies the number of outputs. If you don't specify it, it defaults to 2.
๐ 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
โจ zmq, azmq
Receive commands sent through a libzmq client, and forward them to filters in the filtergraph. It's giving remote control for your filtergraph, lowkey obsessed. ๐
"zmq" and "azmq" work as pass-through filters. "zmq" must be inserted between two video filters, "azmq" between two audio filters. Both are capable of sending messages to any filter type. ๐ซถ
To enable these filters you need to install thelibzmqlibrary and headers and configure FFmpeg with--enable-libzmq. No cap, it just won't be there otherwise.
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). ๐
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. โญ
๐ธ Examples
Look at tools/zmqsend for an example of a zmq client which can be used to send commands processed by these filters. Iykyk. ๐
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. Main character filter energy only. ๐
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
โจ MULTIMEDIA SOURCES โจ
okay besties, here's the tea on the multimedia sources you can actually get your hands on right now โ๐
๐ฌ amovie
Literally the exact same thing as the movie source, except it picks an audio stream by default. That's it. That's the whole vibe. ๐
๐ avsynctest
This one generates an Audio/Video Sync Test for you ๐ โ and ngl, it's kind of iconic. The generated stream periodically flashes a video frame and drops a beep into the audio, so you can go inspect your A/V sync issues like a little detective ๐โจ
It accepts the following options:
size,sโ sets the output video size. Default value ishd720๐framerate,frโ sets the output video frame rate. Default is30.samplerate,srโ sets the output audio sample rate. Default is44100.amplitude,aโ sets the output audio beep amplitude. Default is0.7.period,pโ sets the output audio beep period in seconds. Default is3.delay,dlโ sets the output video flash delay in number of frames. Default is0.cycle,cโ enables cycling of video delays; by default it's disabled.duration,dโ sets stream output duration. By default the duration is unlimited ๐fg,bg,agโ set foreground/background/additional color ๐จ
๐ซถ Commands
This source supports some of the above options as commands. yes bestie, you heard that right.
๐ฟ movie
Reads audio and/or video stream(s) out of a movie container. Main character behavior fr fr ๐
It accepts the following parameters:
filenameโ the name of the resource to read. And no, it's not necessarily a file โ it can also be a device or a stream accessed through some protocol ๐format_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 gets guessed frommovie_nameor 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 is0.streams,sโ specifies the streams to read. You can specify several streams, separated by+. The source will then have as many outputs, in the same order. The 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 automatically selected. Default value is-1. Deprecated โ ๏ธ. If the filter is calledamovie, it will select audio instead of video.loopโ specifies how many times to read the stream in sequence. If the value is0, the stream gets looped infinitely. Default value is1.
heads up bestie ๐จ when the movie is looped the source timestamps are not changed, so it will generate non monotonically increasing timestamps. you've been warned ๐
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 ๐งตformat_optsโ specify format options for the opened file. Format options can be specified 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 also allows overlaying a second video on top of the main input of a filtergraph, as shown in this graph:
input -----------> deltapts0 --> overlay --> output
^
|
movie --> scale--> deltapts1 -------+
๐ธ Examples
- Skip 3.2 seconds from the start of the AVI file
in.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]
๐ Commands
Both movie and amovie support the following commands:
seekโ performs a seek usingav_seek_frame. The syntax is:seek stream_index|timestamp|flagsstream_index: ifstream_indexis-1, a default stream is selected, andtimestampis 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 gets movie duration in AV_TIME_BASE units โฑ๏ธ
๐ง EXTERNAL LIBRARIES ๐ง
FFmpeg can be hooked up with a number 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 ๐ ๏ธโจ
๐ ฐ๏ธ Alliance for Open Media (AOM)
FFmpeg can make use of the AOM library for AV1 decoding and encoding ๐
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) ๐ช
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 occurs 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 you need amdgru-pro version 19.20+ and the amf-amdgpu-pro package (amdgru-pro contains it, but does not install it automatically) ๐
This driver can be installed using the amdgpu-pro-install script in the official amd driver archive.
๐๏ธ 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 ๐ซถ
For Windows, 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.
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 is 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 โจ 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 ๐
๐ต 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>.
๐ป codec2
FFmpeg can make use of the codec2 library for codec2 decoding and encoding. There is currently no native decoder, so libcodec2 must be used for decoding โ ๏ธ
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 ๐งโจ 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.
๐ฆ dav1d
FFmpeg can make use of the dav1d library for AV1 video decoding ๐
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.
๐ง 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.
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), you must upgrade FFmpeg's license to GPL in order to use it ๐ณ important!!
โญ 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.
๐ฎ Game Music Emu ๐ฎ
okay so FFmpeg can make use of the Game Music Emu library to read audio from supported video game music file formats. Like, actual game OST files, we love that for us. Pass --enable-libgme to configure to enable it. Deets live at https://bitbucket.org/mpyne/game-music-emu/overview ๐ฎโจ
โก Intel QuickSync Video โก
FFmpeg can use Intel QuickSync Video (QSV) for accelerated decoding and encoding of multiple codecs. To use QSV, FFmpeg must be linked against the libmfx dispatcher, which loads the actual decoding libraries. (Yes, the dispatcher is the main character here and it loads the real ones. Middle management but make it iconic.)
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.
๐งก Kvazaar ๐งก
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.
๐ต LAME ๐ต
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.
๐ฌ LCEVCdec ๐ฌ
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.
LCEVCdec is under the BSD-3-Clause-Clear License. ๐
๐ฃ๏ธ libilbc ๐ฃ๏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.
๐ผ๏ธ libjxl ๐ผ๏ธ
JPEG XL is an image format intended to fully replace legacy JPEG for an extended period of life. (Legacy JPEG found shaking.) 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.
๐ฌ 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.
๐น ModPlug ๐น
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. Tracker files bestie, it's giving 1996 in the best way ๐
๐๏ธ OpenCORE, VisualOn, and Fraunhofer libraries ๐๏ธ
Spun off Google Android sources, OpenCore, VisualOn and Fraunhofer libraries provide encoders for a number of audio codecs.
OpenCORE and VisualOn libraries are under the Apache License 2.0 (seehttp://www.apache.org/licenses/LICENSE-2.0for 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-version3to configure in order to use it. โ ๏ธ
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. โ ๏ธ
๐ 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.
๐ VisualOn AMR-WB encoder library ๐
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.
๐ง Fraunhofer AAC library ๐ง
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.
๐ 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.
๐ฑ LC3 library ๐ฑ
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.
๐ OpenH264 ๐
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; 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). Not me warning you that the built-in one ate and left no crumbs, but like, it did ๐
๐พ OpenJPEG ๐พ
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.
๐ฆ 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.
๐ SVT-AV1 ๐
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.
๐ธ SVT-JPEG-XS ๐ธ
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.
๐ถ TwoLAME ๐ถ
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.
๐ฆ 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/.
Due to security concerns, Vapoursynth scripts will not be autodetected so the input format has to be forced. For ff* CLI tools, add-f vapoursynthbefore the input-i yourscript.vpy. ๐ Please don't skip this, bestie, it's for your own safety.
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.
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. โ ๏ธ
๐ 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.
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. โ ๏ธ
๐๏ธ 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.
๐๏ธ xavs2 ๐๏ธ
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.
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. โ ๏ธ
๐ง eXtra-fast Essential Video Encoder (XEVE) ๐ง
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.
๐ง eXtra-fast Essential Video Decoder (XEVD) ๐ง
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.
๐บ ZVBI ๐บ
ZVBI is a VBI decoding library which can be used by FFmpeg to decode DVB teletext pages and DVB teletext subtitles.
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 actual full tea โ โ this section is just the vibe check version.
๐ผ File Formats ๐ผ
FFmpeg supports the following file formats through the libavformat library:
Heads up bestie: each entry below shows the Encoding column and the Decoding column from the original list, so an X means yes and (blank) means it's not supported on that side. The comment line underneath is the note that came with it โจ
3dostrโ Encoding: (blank) ยท Decoding: X4xmโ Encoding: (blank) ยท Decoding: X- 4X Technologies format, used in some games.
8088flex TMVโ Encoding: (blank) ยท Decoding: XAAXโ Encoding: (blank) ยท Decoding: X- Audible Enhanced Audio format, used in audiobooks.
AAโ Encoding: (blank) ยท Decoding: X- Audible Format 2, 3, and 4, used in audiobooks.
ACT Voiceโ Encoding: (blank) ยท Decoding: X- contains G.729 audio
Adobe Filmstripโ Encoding: X ยท Decoding: XAudio IFF (AIFF)โ Encoding: X ยท Decoding: XAmerican Laser Games MMโ Encoding: (blank) ยท Decoding: X- Multimedia format used in games like Mad Dog McCree.
Okay bestie, deep breath โ we're in the thick of the format list now and there's genuinely like a hundred of these, so let's go ๐ (and yeah, ๐ฅ means demux, ๐ค means mux โ same deal as always)
3GPP AMRโ ๐ฅ demux + ๐ค mux, both directions, we love a versatile iconAmazing Studio Packed Animation Fileโ ๐ค mux only ยท Multimedia format used in game Heart Of Darkness. (niche but iconic)Apple HTTP Live Streamingโ ๐ค mux onlyArtworx Data Formatโ ๐ค mux onlyInterplay ACMโ ๐ค mux only ยท Audio only format used in some Interplay games.ADPโ ๐ค mux only ยท Audio format used on the Nintendo Gamecube.AFCโ ๐ค mux only ยท Audio format used on the Nintendo Gamecube. (gamecube girls stay winning)ADS/SS2โ ๐ค mux only ยท Audio format used on the PS2.APNGโ ๐ฅ demux + ๐ค muxASFโ ๐ฅ demux + ๐ค mux ยท Advanced / Active Streaming Format.ASTโ ๐ฅ demux + ๐ค mux ยท Audio format used on the Nintendo Wii.AVIโ ๐ฅ demux + ๐ค mux, the classic, the momentAviSynthโ ๐ค mux onlyAVRโ ๐ค mux only ยท Audio format used on Mac.AVSโ ๐ค mux only ยท Multimedia format used by the Creature Shock game.Beam Software SIFFโ ๐ค mux only ยท Audio and video format used in some games by Beam Software.Bethesda Softworks VIDโ ๐ค mux only ยท Used in some games from Bethesda Softworks.Binary textโ ๐ค mux onlyBinkโ ๐ค mux only ยท Multimedia format used by many games.Bink Audioโ ๐ค mux only ยท Audio only multimedia format used by some games.Bitmap Brothers JVโ ๐ค mux only ยท Used in Z and Z95 games.BRPโ ๐ค mux only ยท Argonaut Games format.Brute Force & Ignoranceโ ๐ค mux only ยท Used in the game Flash Traffic: City of Angels.BFSTMโ ๐ค mux only ยท Audio format used on the Nintendo WiiU (based on BRSTM).BRSTMโ ๐ค mux only ยท Audio format used on the Nintendo Wii.BW64โ ๐ค mux only ยท Broadcast Wave 64bit.BWFโ ๐ฅ demux + ๐ค muxcodec2 (raw)โ ๐ฅ demux + ๐ค mux ยท Must be given-modeformat option to decode correctly. (no cap, do NOT forget the-mode, she will not decode for you)codec2 (.c2 files)โ ๐ฅ demux + ๐ค mux ยท Contains header with version and mode info, simplifying playback. (the self-sufficient version, we stan)CRI ADXโ ๐ฅ demux + ๐ค mux ยท Audio-only format used in console video games.CRI AIXโ ๐ค mux onlyCRI HCAโ ๐ค mux only ยท Audio-only format used in console video games.Discworld II BMVโ ๐ค mux onlyInterplay C93โ ๐ค mux only ยท Used in the game Cyberia from Interplay.Delphine Software International CINโ ๐ค mux only ยท Multimedia format used by Delphine Software games.Digital Speech Standard (DSS)โ ๐ค mux onlyCD+Gโ ๐ค mux only ยท Video format used by CD+G karaoke disks (karaoke night is LOADING ๐ค)Phantom Cineโ ๐ค mux onlyCommodore CDXLโ ๐ค mux only ยท Amiga CD video formatCore Audio Formatโ ๐ฅ demux + ๐ค mux ยท Apple Core Audio FormatCRC testing formatโ ๐ฅ demux only (no mux bestie, testing only)Creative Voiceโ ๐ฅ demux + ๐ค mux ยท Created for the Sound Blaster Pro.CRYO APCโ ๐ค mux only ยท Audio format used in some games by CRYO Interactive Entertainment.D-Cinema audioโ ๐ฅ demux + ๐ค muxDeluxe Paint Animationโ ๐ค mux onlyDCSTRโ ๐ค mux onlyDFAโ ๐ค mux only ยท This format is used in Chronomaster gameDirectDraw Surfaceโ ๐ค mux onlyDSD Stream File (DSF)โ ๐ค mux onlyDV videoโ ๐ฅ demux + ๐ค muxDXAโ ๐ค mux only ยท This format is used in the non-Windows version of the Feeble Files game and different game cutscenes repacked for use with ScummVM.Electronic Arts cdataโ ๐ค mux onlyElectronic Arts Multimediaโ ๐ค mux only ยท Used in various EA games; files have extensions likeWVEandUV2.Ensoniq Paris Audio Fileโ ๐ค mux onlyFFM (FFserver live feed)โ ๐ฅ demux + ๐ค muxFlash (SWF)โ ๐ฅ demux + ๐ค muxFlash 9 (AVM2)โ ๐ฅ demux + ๐ค mux ยท Only embedded audio is decoded. (just the audio, she's doing her best)FLI/FLC/FLX animationโ ๐ค mux only ยท.fli/.flcfilesFlash Video (FLV)โ ๐ฅ demux + ๐ค mux ยท Macromedia Flash video filesframecrc testing formatโ ๐ฅ demux onlyFunCom ISSโ ๐ค mux only ยท Audio format used in various games from FunCom like The Longest Journey.G.723.1โ ๐ฅ demux + ๐ค muxG.726โ ๐ค mux only ยท Both left- and right-justified.G.729 BITโ ๐ฅ demux + ๐ค muxG.729 rawโ ๐ค mux onlyGENHโ ๐ค mux only ยท Audio format for various games.GIF Animationโ ๐ฅ demux + ๐ค muxGXFโ ๐ฅ demux + ๐ค mux ยท General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.HNMโ ๐ค mux only ยท Only version 4 supported, used in some games from Cryo InteractiveiCEDraw Fileโ ๐ค mux onlyICOโ ๐ฅ demux + ๐ค mux ยท Microsoft Windows ICOid Quake II CIN videoโ ๐ค mux onlyid RoQโ ๐ฅ demux + ๐ค mux ยท Used in Quake III, Jedi Knight 2 and other computer games.IEC61937 encapsulationโ ๐ฅ demux + ๐ค muxIFFโ ๐ค mux only ยท Interchange File FormatIFVโ ๐ค mux only ยท A format used by some old CCTV DVRs.iLBCโ ๐ฅ demux + ๐ค muxInterplay MVEโ ๐ค mux only ยท Format used in various Interplay computer games.Iterated Systems ClearVideoโ ๐ค mux only ยท I-frames onlyIV8โ ๐ค mux only ยท A format generated by IndigoVision 8000 video server.IVF (On2)โ ๐ฅ demux + ๐ค mux ยท A format used by libvpxInternet Video Recordingโ ๐ค mux onlyIRCAMโ ๐ฅ demux + ๐ค muxLAFโ ๐ค mux only ยท Limitless Audio FormatLATMโ ๐ฅ demux + ๐ค muxLMLM4โ ๐ค mux only ยท Used by Linux Media Labs MPEG-4 PCI boardsLOASโ ๐ค mux only ยท contains LATM multiplexed AAC audioLRCโ ๐ฅ demux + ๐ค muxLVFโ ๐ค mux onlyLXFโ ๐ค mux only ยท VR native stream format, used by Leitch/Harris' video servers.Magic Lantern Video (MLV)โ ๐ค mux onlyMatroskaโ ๐ฅ demux + ๐ค muxMatroska audioโ ๐ฅ demux onlyFFmpeg metadataโ ๐ฅ demux + ๐ค mux ยท Metadata in text format.MAXIS XAโ ๐ค mux only ยท Used in Sim City 3000; file extension.xa.MCAโ ๐ค mux only ยท Used in some games from Capcom; file extension.mca.MD Studioโ ๐ค mux onlyMetal Gear Solid: The Twin Snakesโ ๐ค mux onlyMegalux Frameโ ๐ค mux only ยท Used by Megalux Ultimate PaintMobiClip MODSโ ๐ค mux onlyMobiClip MOFLEXโ ๐ค mux onlyMobotix .mxgโ ๐ค mux onlyMonkey's Audioโ ๐ค mux onlyMotion Pixels MVIโ ๐ค mux onlyMOV/QuickTime/MP4โ ๐ฅ demux + ๐ค mux ยท 3GP, 3GP2, PSP, iPod variants supported (the nepo baby of containers, and honestly? deserved)MP2โ ๐ฅ demux + ๐ค muxMP3โ ๐ฅ demux + ๐ค muxMPEG-1 Systemโ ๐ฅ demux + ๐ค mux ยท muxed audio and video, VCD format supportedMPEG-PS (program stream)โ ๐ฅ demux + ๐ค mux ยท also known asVOBfile, SVCD and DVD format supportedMPEG-TS (transport stream)โ ๐ฅ demux + ๐ค mux ยท also known as DVB Transport StreamMPEG-4โ ๐ฅ demux + ๐ค mux ยท MPEG-4 is a variant of QuickTime.MSFโ ๐ค mux only ยท Audio format used on the PS3.Mirillis FIC videoโ ๐ค mux only ยท No cursor rendering. (sorry bestie, no cursor for you)MIDI Sample Dump Standardโ ๐ค mux onlyMIME multipart JPEGโ ๐ฅ demux onlyMSN TCP webcamโ ๐ค mux only ยท Used by MSN Messenger webcam streams.MTVโ ๐ค mux onlyMusepackโ ๐ค mux onlyMusepack SV8โ ๐ค mux onlyMaterial eXchange Format (MXF)โ ๐ฅ demux + ๐ค mux ยท SMPTE 377M, used by D-Cinema, broadcast industry.Material eXchange Format (MXF), D-10 Mappingโ ๐ฅ demux + ๐ค mux ยท SMPTE 386M, D-10/IMX Mapping.NC camera feedโ ๐ค mux only ยท NC (AVIP NC4600) camera streamsNIST SPeech HEader REsourcesโ ๐ค mux onlyComputerized Speech Lab NSPโ ๐ค mux onlyNTT TwinVQ (VQF)โ ๐ค mux only ยท Nippon Telegraph and Telephone Corporation TwinVQ.Nullsoft Streaming Videoโ ๐ค mux onlyNuppelVideoโ ๐ค mux onlyNUTโ ๐ฅ demux + ๐ค mux ยท NUT Open Container FormatOggโ ๐ฅ demux + ๐ค muxPlaystation Portable PMPโ ๐ค mux onlyPortable Voice Formatโ ๐ค mux onlyRK Audio (RKA)โ ๐ค mux onlyTechnoTrend PVAโ ๐ค mux only ยท Used by TechnoTrend DVB PCI boards.
ngl that's a LOT of formats, and we're not even done yet โ keep scrolling bestie, the list continues ๐
okay so we're still deep in the format catalogue โ the two columns are demux and mux (โ
= yes, โ = no), and honestly? it's giving phonebook but make it slay ๐
QCPโ demux โ ยท mux โraw ADTS (AAC)โ demux โ ยท mux โraw AC-3โ demux โ ยท mux โraw AMR-NBโ demux โ ยท mux โraw AMR-WBโ demux โ ยท mux โraw APACโ demux โ ยท mux โraw APVโ demux โ ยท mux โraw aptXโ demux โ ยท mux โraw aptX HDโ demux โ ยท mux โraw Bonkโ demux โ ยท mux โraw Chinese AVS videoโ demux โ ยท mux โraw DFPWMโ demux โ ยท mux โraw Diracโ demux โ ยท mux โraw DNxHDโ demux โ ยท mux โraw DTSโ demux โ ยท mux โraw DTS-HDโ demux โ ยท mux โraw E-AC-3โ demux โ ยท mux โraw EVCโ demux โ ยท mux โraw FLACโ demux โ ยท mux โraw G.728โ demux โ ยท mux โraw GSMโ demux โ ยท mux โraw H.261โ demux โ ยท mux โraw H.263โ demux โ ยท mux โraw H.264โ demux โ ยท mux โraw HEVCโ demux โ ยท mux โraw Ingenient MJPEGโ demux โ ยท mux โraw MJPEGโ demux โ ยท mux โraw MLPโ demux โ ยท mux โraw MPEGโ demux โ ยท mux โraw MPEG-1โ demux โ ยท mux โraw MPEG-2โ demux โ ยท mux โraw MPEG-4โ demux โ ยท mux โraw NULLโ demux โ ยท mux โraw videoโ demux โ ยท mux โraw id RoQโ demux โ ยท mux โraw OBUโ demux โ ยท mux โraw OSQโ demux โ ยท mux โraw SBCโ demux โ ยท mux โraw Shortenโ demux โ ยท mux โraw TAKโ demux โ ยท mux โraw TrueHDโ demux โ ยท mux โraw VC-1โ demux โ ยท mux โraw PCM A-lawโ demux โ ยท mux โraw PCM mu-lawโ demux โ ยท mux โraw PCM Archimedes VIDCโ demux โ ยท mux โraw PCM signed 8 bitโ demux โ ยท mux โraw PCM signed 16 bit big-endianโ demux โ ยท mux โraw PCM signed 16 bit little-endianโ demux โ ยท mux โraw PCM signed 24 bit big-endianโ demux โ ยท mux โraw PCM signed 24 bit little-endianโ demux โ ยท mux โraw PCM signed 32 bit big-endianโ demux โ ยท mux โraw PCM signed 32 bit little-endianโ demux โ ยท mux โraw PCM signed 64 bit big-endianโ demux โ ยท mux โraw PCM signed 64 bit little-endianโ demux โ ยท mux โraw PCM unsigned 8 bitโ demux โ ยท mux โraw PCM unsigned 16 bit big-endianโ demux โ ยท mux โraw PCM unsigned 16 bit little-endianโ demux โ ยท mux โraw PCM unsigned 24 bit big-endianโ demux โ ยท mux โraw PCM unsigned 24 bit little-endianโ demux โ ยท mux โraw PCM unsigned 32 bit big-endianโ demux โ ยท mux โraw PCM unsigned 32 bit little-endianโ demux โ ยท mux โraw PCM 16.8 floating point little-endianโ demux โ ยท mux โraw PCM 24.0 floating point little-endianโ demux โ ยท mux โraw PCM floating-point 32 bit big-endianโ demux โ ยท mux โraw PCM floating-point 32 bit little-endianโ demux โ ยท mux โraw PCM floating-point 64 bit big-endianโ demux โ ยท mux โraw PCM floating-point 64 bit little-endianโ demux โ ยท mux โRDTโ demux โ ยท mux โREDCODE R3Dโ demux โ ยท mux โ โ File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio. ๐ฅRealMediaโ demux โ ยท mux โRedirectorโ demux โ ยท mux โRedSparkโ demux โ ยท mux โRenderware TeXture Dictionaryโ demux โ ยท mux โResolume DXVโ demux โ ยท mux โ โ Encoding is only supported for the DXT1 (Normal Quality, No Alpha) texture format.RF64โ demux โ ยท mux โRL2โ demux โ ยท mux โ โ Audio and video format used in some games by Entertainment Software Partners.RPL/ARMovieโ demux โ ยท mux โLego Mindstorms RSOโ demux โ ยท mux โRSDโ demux โ ยท mux โRTMPโ demux โ ยท mux โ โ Output is performed by publishing stream to RTMP serverRTPโ demux โ ยท mux โRTSPโ demux โ ยท mux โSample Dump eXchangeโ demux โ ยท mux โSAPโ demux โ ยท mux โSBGโ demux โ ยท mux โSDNSโ demux โ ยท mux โSDPโ demux โ ยท mux โSERโ demux โ ยท mux โDigital Pictures SGAโ demux โ ยท mux โSega FILM/CPKโ demux โ ยท mux โ โ Used in many Sega Saturn console games. ๐ฎSilicon Graphics Movieโ demux โ ยท mux โSierra SOLโ demux โ ยท mux โ โ .sol files used in Sierra Online games.Sierra VMDโ demux โ ยท mux โ โ Used in Sierra CD-ROM games.Smackerโ demux โ ยท mux โ โ Multimedia format used by many games.SMJPEGโ demux โ ยท mux โ โ Used in certain Loki game ports.SMPTE 337M encapsulationโ demux โ ยท mux โSmushโ demux โ ยท mux โ โ Multimedia format used in some LucasArts games.Sony OpenMG (OMA)โ demux โ ยท mux โ โ Audio format used in Sony Sonic Stage and Sony Vegas.Sony PlayStation STRโ demux โ ยท mux โSony Wave64 (W64)โ demux โ ยท mux โSoX native formatโ demux โ ยท mux โSUN AU formatโ demux โ ยท mux โSUP raw PGS subtitlesโ demux โ ยท mux โSVAGโ demux โ ยท mux โ โ Audio format used in Konami PS2 games.TDSCโ demux โ ยท mux โText filesโ demux โ ยท mux โTHPโ demux โ ยท mux โ โ Used on the Nintendo GameCube. ๐Tiertex Limited SEQโ demux โ ยท mux โ โ Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.True Audioโ demux โ ยท mux โVAGโ demux โ ยท mux โ โ Audio format used in many Sony PS2 games.VC-1 test bitstreamโ demux โ ยท mux โVidvox Hapโ demux โ ยท mux โVivoโ demux โ ยท mux โVPKโ demux โ ยท mux โ โ Audio format used in Sony PS games.Marble WADYโ demux โ ยท mux โWAVโ demux โ ยท mux โWaveform Archiverโ demux โ ยท mux โWavPackโ demux โ ยท mux โWebMโ demux โ ยท mux โWindows Televison (WTV)โ demux โ ยท mux โWing Commander III movieโ demux โ ยท mux โ โ Multimedia format used in Origin's Wing Commander III computer game.Westwood Studios audioโ demux โ ยท mux โ โ Multimedia format used in Westwood Studios games.Westwood Studios VQAโ demux โ ยท mux โ โ Multimedia format used in Westwood Studios games.Wideband Single-bit Data (WSD)โ demux โ ยท mux โWVEโ demux โ ยท mux โKonami XMDโ demux โ ยท mux โXMVโ demux โ ยท mux โ โ Microsoft video container used in Xbox games.XVAGโ demux โ ยท mux โ โ Audio format used on the PS3.xWMAโ demux โ ยท mux โ โ Microsoft audio container used by XAudio 2.eXtended BINary text (XBIN)โ demux โ ยท mux โYUV4MPEG pipeโ demux โ ยท mux โPsygnosis YOPโ demux โ ยท mux โ
and the official caption, word for word bestie, no notes:
"X" means that the feature in that column (encoding / decoding) is supported.
๐ผ๏ธ Image Formats
okay so here's the cute part: FFmpeg can read and write images for each frame of a video sequence, like literally frame by frame ๐ธ The following image formats are supported, and the columns go Name ยท Encoding ยท Decoding ยท Comments:
.Y.U.Vโ encode โ ยท decode โ โ one raw file per componentAlias PIXโ encode โ ยท decode โ โ Alias/Wavefront PIX image formatanimated GIFโ encode โ ยท decode โAPNGโ encode โ ยท decode โ โ Animated Portable Network GraphicsBMPโ encode โ ยท decode โ โ Microsoft BMP imageBRender PIXโ encode โ ยท decode โ โ Argonaut BRender 3D engine image format.CRIโ encode โ ยท decode โ โ Cintel RAWDPXโ encode โ ยท decode โ โ Digital Picture ExchangeEXRโ encode โ ยท decode โ โ OpenEXRFITSโ encode โ ยท decode โ โ Flexible Image Transport SystemHDRโ encode โ ยท decode โ โ Radiance HDR RGBE Image formatIMGโ encode โ ยท decode โ โ GEM Raster imageJPEGโ encode โ ยท decode โ โ Progressive JPEG is not supported. โ ๏ธJPEG 2000โ encode โ ยท decode โJPEG-LSโ encode โ ยท decode โJPEG-XSโ encodeEยท decodeEโ Supported through external library libsvtjpegxsLJPEGโ encode โ ยท decode โ โ Lossless JPEGMedia 100โ encode โ ยท decode โMSPโ encode โ ยท decode โ โ Microsoft Paint imagePAMโ encode โ ยท decode โ โ PAM is a PNM extension with alpha support.PBMโ encode โ ยท decode โ โ Portable BitMap imagePCDโ encode โ ยท decode โ โ PhotoCDPCXโ encode โ ยท decode โ โ PC PaintbrushPFMโ encode โ ยท decode โ โ Portable FloatMap imagePGMโ encode โ ยท decode โ โ Portable GrayMap imagePGMYUVโ encode โ ยท decode โ โ PGM with U and V components in YUV 4:2:0PGXโ encode โ ยท decode โ โ PGX file decoderPHMโ encode โ ยท decode โ โ Portable HalfFloatMap imagePICโ encode โ ยท decode โ โ Pictor/PC PaintPNGโ encode โ ยท decode โ โ Portable Network Graphics image ๐PPMโ encode โ ยท decode โ โ Portable PixelMap imagePSDโ encode โ ยท decode โ โ PhotoshopPTXโ encode โ ยท decode โ โ V.Flash PTX formatQOIโ encode โ ยท decode โ โ Quite OK Image formatSGIโ encode โ ยท decode โ โ SGI RGB image formatSun Rasterfileโ encode โ ยท decode โ โ Sun RAS image formatTIFFโ encode โ ยท decode โ โ YUV, JPEG and some extension is not supported yet.Truevision Targaโ encode โ ยท decode โ โ Targa (.TGA) image formatVBNโ encode โ ยท decode โ โ Vizrt Binary Image formatWBMPโ encode โ ยท decode โ โ Wireless Application Protocol Bitmap image formatWebPโ encodeEยท decode โ โ WebP image format, encoding supported through external library libwebpXBMโ encode โ ยท decode โ โ X BitMap image formatXFaceโ encode โ ยท decode โ โ X-Face image formatXPMโ encode โ ยท decode โ โ X PixMap image formatXWDโ encode โ ยท decode โ โ X Window Dump image format
and the two little legend lines, verbatim because they matter:
"X" means that the feature in that column (encoding / decoding) is supported.
"E" means that support is provided through an external library.
๐ฌ Video Codecs
okay last little bit for this stretch โ the video codec table, columns again Name ยท Encoding ยท Decoding ยท Comments. Here's where we're at:
4X Movieโ encode โ ยท decode โ โ Used in certain computer games.8088flex TMVโ ๐ฅ decode onlyA64 multicolorโ ๐ค encode only- Creates video suitable to be played on a commodore 64 (multicolor mode). iconic tbqh ๐
Amazing Studio PAF Videoโ ๐ฅ decode onlyAmerican Laser Games MMโ ๐ฅ decode only- Used in games like Mad Dog McCree.
Amuse Graphics Movieโ ๐ฅ decode onlyAMV Videoโ ๐ encode + decode- Used in Chinese MP3 players. yes bestie, players, that's not a typo ๐
ANSI/ASCII artโ ๐ฅ decode onlyApple Intermediate Codecโ ๐ฅ decode onlyApple MJPEG-Bโ ๐ฅ decode onlyApple Pixletโ ๐ฅ decode onlyApple ProResโ ๐ encode + decode- fourcc:
apch,apcn,apcs,apco,ap4h,ap4x
- fourcc:
Apple QuickDrawโ ๐ฅ decode only- fourcc:
qdrw
- fourcc:
APVโ ๐ฅ decode onlyArgonaut Videoโ ๐ฅ decode only- Used in some Argonaut games.
Asus v1โ ๐ encode + decode- fourcc:
ASV1
- fourcc:
Asus v2โ ๐ encode + decode- fourcc:
ASV2
- fourcc:
ATI VCR1โ ๐ฅ decode only- fourcc:
VCR1
- fourcc:
ATI VCR2โ ๐ฅ decode only- fourcc:
VCR2
- fourcc:
Auravision Auraโ ๐ฅ decode onlyAuravision Aura 2โ ๐ฅ decode onlyAutodesk Animator Flic videoโ ๐ฅ decode onlyAutodesk RLEโ ๐ฅ decode only- fourcc:
AASC
- fourcc:
AV1โ ๐ external-lib encode + ๐ external-lib decode- Supported through external libraries
libaom,libdav1d,librav1eandlibsvtav1
- Supported through external libraries
Avid 1:1 10-bit RGB Packerโ ๐ encode + decode- fourcc:
AVrp
- fourcc:
AVS (Audio Video Standard) videoโ ๐ฅ decode only- Video encoding used by the Creature Shock game.
AVS2-P2/IEEE1857.4โ ๐ external-lib encode + ๐ external-lib decode- Supported through external libraries
libxavs2andlibdavs2
- Supported through external libraries
AVS3-P2/IEEE1857.10โ ๐ external-lib decode only- Supported through external library
libuavs3d
- Supported through external library
AYUVโ ๐ encode + decode- Microsoft uncompressed packed 4:4:4:4
Beam Software VBโ ๐ฅ decode onlyBethesda VID videoโ ๐ฅ decode only- Used in some games from Bethesda Softworks.
Bink Videoโ ๐ฅ decode onlyBitJazz SheerVideoโ ๐ฅ decode onlyBitmap Brothers JV videoโ ๐ฅ decode onlyy41p Brooktree uncompressed 4:1:1 12-bitโ ๐ encode + decodeBrooktree ProSumer Videoโ ๐ฅ decode only- fourcc:
BT20
- fourcc:
Brute Force & Ignoranceโ ๐ฅ decode only- Used in the game Flash Traffic: City of Angels.
C93 videoโ ๐ฅ decode only- Codec used in Cyberia game.
CamStudioโ ๐ฅ decode only- fourcc:
CSCD
- fourcc:
CD+Gโ ๐ฅ decode only- Video codec for CD+G karaoke disks ๐ karaoke girlies rise
CDXLโ ๐ฅ decode only- Amiga CD video codec
Chinese AVS videoโ ๐ external-lib encode + ๐ฅ decode- AVS1-P2, JiZhun profile, encoding through external library
libxavs
- AVS1-P2, JiZhun profile, encoding through external library
Delphine Software International CIN videoโ ๐ฅ decode only- Codec used in Delphine Software International games.
Discworld II BMV Videoโ ๐ฅ decode onlyCineForm HDโ ๐ encode + decodeCanopus HQโ ๐ฅ decode onlyCanopus HQAโ ๐ฅ decode onlyCanopus HQXโ ๐ฅ decode onlyCanopus Lossless Codecโ ๐ฅ decode onlyCDToonsโ ๐ฅ decode only- Codec used in various Broderbund games.
Cinepakโ ๐ฅ decode onlyCirrus Logic AccuPakโ ๐ encode + decode- fourcc:
CLJR
- fourcc:
CPiA Video Formatโ ๐ฅ decode onlyCreative YUV (CYUV)โ ๐ฅ decode onlyDFAโ ๐ฅ decode only- Codec used in Chronomaster game.
Diracโ ๐ external-lib encode + ๐ฅ decode- supported though the native
vc2(Dirac Pro) encoder
- supported though the native
Deluxe Paint Animationโ ๐ฅ decode onlyDNxHDโ ๐ encode + decode- aka SMPTE VC3
Duck TrueMotion 1.0โ ๐ฅ decode only- fourcc:
DUCK
- fourcc:
Duck TrueMotion 2.0โ ๐ฅ decode only- fourcc:
TM20
- fourcc:
Duck TrueMotion 2.0 RTโ ๐ฅ decode only- fourcc:
TR20
- fourcc:
DV (Digital Video)โ ๐ encode + decodeDxtory capture formatโ ๐ฅ decode onlyFeeble Files/ScummVM DXAโ ๐ฅ decode only- Codec originally used in Feeble Files game.
Electronic Arts CMV videoโ ๐ฅ decode only- Used in NHL 95 game.
Electronic Arts Madcow videoโ ๐ฅ decode onlyElectronic Arts TGV videoโ ๐ฅ decode onlyElectronic Arts TGQ videoโ ๐ฅ decode onlyElectronic Arts TQI videoโ ๐ฅ decode onlyEscape 124โ ๐ฅ decode onlyEscape 130โ ๐ฅ decode onlyEVC / MPEG-5 Part 1โ ๐ external-lib encode + ๐ external-lib decode- encoding and decoding supported through external libraries
libxeveandlibxevd
- encoding and decoding supported through external libraries
FFmpeg video codec #1โ ๐ encode + decode- lossless codec (fourcc:
FFV1)
- lossless codec (fourcc:
Flash Screen Video v1โ ๐ encode + decode- fourcc:
FSV1
- fourcc:
Flash Screen Video v2โ ๐ encode + decodeFlash Video (FLV)โ ๐ encode + decode- Sorenson H.263 used in Flash
FM Screen Capture Codecโ ๐ฅ decode onlyForward Uncompressedโ ๐ฅ decode onlyFrapsโ ๐ฅ decode onlyGo2Meetingโ ๐ฅ decode only- fourcc:
G2M2, G2M3
- fourcc:
Go2Webinarโ ๐ฅ decode only- fourcc:
G2M4
- fourcc:
Gremlin Digital Videoโ ๐ฅ decode onlyH.261โ ๐ encode + decodeH.263 / H.263-1996โ ๐ encode + decodeH.263+ / H.263-1998 / H.263 version 2โ ๐ encode + decodeH.264 / AVC / MPEG-4 AVC / MPEG-4 part 10โ ๐ external-lib encode + ๐ฅ decode- encoding supported through external library
libx264and OpenH264
- encoding supported through external library
HEVCโ ๐ encode + decode- encoding supported through external library
libx265andlibkvazaar
- encoding supported through external library
HNM version 4โ ๐ฅ decode onlyHuffYUVโ ๐ encode + decodeHuffYUV FFmpeg variantโ ๐ encode + decodeIBM Ultimotionโ ๐ฅ decode only- fourcc:
ULTI
- fourcc:
id Cinematic videoโ ๐ฅ decode only- Used in Quake II.
id RoQ videoโ ๐ encode + decode- Used in Quake III, Jedi Knight 2, other computer games. gamer history fr ๐ฎ
IFF ILBMโ ๐ฅ decode only- IFF interleaved bitmap
IFF ByteRun1โ ๐ฅ decode only- IFF run length encoded bitmap
Infinity IMM4โ ๐ฅ decode onlyIntel H.263โ ๐ฅ decode onlyIntel Indeo 2โ ๐ฅ decode onlyIntel Indeo 3โ ๐ฅ decode onlyIntel Indeo 4โ ๐ฅ decode onlyIntel Indeo 5โ ๐ฅ decode onlyInterplay C93โ ๐ฅ decode only- Used in the game Cyberia from Interplay.
Interplay MVE videoโ ๐ฅ decode only- Used in Interplay
.MVEfiles.
- Used in Interplay
J2Kโ ๐ encode + decodeKarl Morton's video codecโ ๐ฅ decode only- Codec used in Worms games.
Kega Game Video (KGV1)โ ๐ฅ decode only- Kega emulator screen capture codec.
Lagarithโ ๐ฅ decode onlyLCEVC / MPEG-5 LCEVC / MPEG-5 Part 2โ ๐ external-lib decode only- decoding supported through external library
liblcevc-dec
- decoding supported through external library
LCL (LossLess Codec Library) MSZHโ ๐ฅ decode onlyLCL (LossLess Codec Library) ZLIBโ ๐ external-lib encode + ๐ external-lib decodeLEAD MCMPโ ๐ฅ decode onlyLOCOโ ๐ฅ decode onlyLucasArts SANM/Smushโ ๐ฅ decode only- Used in LucasArts games / SMUSH animations.
lossless MJPEGโ ๐ encode + decodeMagicYUV Videoโ ๐ encode + decodeMandsoft Screen Capture Codecโ ๐ฅ decode onlyMicrosoft ATC Screenโ ๐ฅ decode only- Also known as Microsoft Screen 3.
Microsoft Expression Encoder Screenโ ๐ฅ decode only- Also known as Microsoft Titanium Screen 2.
Microsoft RLEโ ๐ encode + decodeMicrosoft Screen 1โ ๐ฅ decode only- Also known as Windows Media Video V7 Screen.
Microsoft Screen 2โ ๐ฅ decode only- Also known as Windows Media Video V9 Screen.
Microsoft Video 1โ ๐ฅ decode onlyMimicโ ๐ฅ decode only- Used in MSN Messenger Webcam streams.
Miro VideoXLโ ๐ฅ decode only- fourcc:
VIXL
- fourcc:
MJPEG (Motion JPEG)โ ๐ encode + decodeMobotix MxPEG videoโ ๐ฅ decode onlyMotion Pixels videoโ ๐ฅ decode onlyMPEG-1 videoโ ๐ encode + decodeMPEG-2 videoโ ๐ encode + decodeMPEG-4 part 2โ ๐ encode + decodelibxvidcorecan be used alternatively for encoding.
MPEG-4 part 2 Microsoft variant version 1โ ๐ฅ decode onlyMPEG-4 part 2 Microsoft variant version 2โ ๐ encode + decodeMPEG-4 part 2 Microsoft variant version 3โ ๐ encode + decodeNewtek SpeedHQโ ๐ encode + decodeNintendo Gamecube THP videoโ ๐ฅ decode onlyNotchLCโ ๐ฅ decode onlyNuppelVideo/RTjpegโ ๐ฅ decode only- Video encoding used in NuppelVideo files.
On2 VP3โ ๐ฅ decode only- still experimental ๐
On2 VP4โ ๐ฅ decode only- fourcc:
VP40
- fourcc:
On2 VP5โ ๐ฅ decode only- fourcc:
VP50
- fourcc:
On2 VP6โ ๐ฅ decode only- fourcc:
VP60,VP61,VP62
- fourcc:
On2 VP7โ ๐ฅ decode only- fourcc:
VP70,VP71
- fourcc:
VP8โ ๐ external-lib encode + ๐ฅ decode- fourcc:
VP80, encoding supported through external librarylibvpx
- fourcc:
VP9โ ๐ external-lib encode + ๐ฅ decode- encoding supported through external library
libvpx
- encoding supported through external library
Pinnacle TARGA CineWave YUV16โ ๐ฅ decode only- fourcc:
Y216
- fourcc:
Q-team QPEGโ ๐ฅ decode only- fourccs:
QPEG, Q1.0, Q1.1
- fourccs:
QuickTime 8BPS videoโ ๐ฅ decode onlyQuickTime Animation (RLE) videoโ ๐ encode + decode- fourcc:
'rle 'โ yes the space is part of it, don't come for me ๐ญ
- fourcc:
QuickTime Graphics (SMC)โ ๐ encode + decode- fourcc:
'smc '
- fourcc:
QuickTime video (RPZA)โ ๐ encode + decode- fourcc:
rpza
- fourcc:
R10K AJA Kona 10-bit RGB Codecโ ๐ encode + decodeR210 Quicktime Uncompressed RGB 10-bitโ ๐ encode + decodeRaw Videoโ ๐ encode + decodeRealVideo 1.0โ ๐ encode + decodeRealVideo 2.0โ ๐ encode + decodeRealVideo 3.0โ ๐ฅ decode only- still far from ideal ๐ฌ
RealVideo 4.0โ ๐ฅ decode onlyRealVideo 6.0โ ๐ฅ decode onlyRenderware TXD (TeXture Dictionary)โ ๐ฅ decode only- Texture dictionaries used by the Renderware Engine.
RivaTuner Videoโ ๐ฅ decode only- fourcc:
'RTV1'
- fourcc:
RL2 videoโ ๐ฅ decode only- used in some games by Entertainment Software Partners
ScreenPressorโ decodeX๐ฌScreenpressoโ decodeXScreen Recorder Gold Codecโ decodeXSierra VMD videoโ decodeXโ used in Sierra VMD files ๐พSilicon Graphics Motion Video Compressor 1 (MVC1)โ decodeXSilicon Graphics Motion Video Compressor 2 (MVC2)โ decodeXSilicon Graphics RLE 8-bit videoโ decodeXSmacker videoโ decodeXโ the video encoding used in Smacker ๐ฎSMPTE VC-1โ decodeXSnowโ encodeX, decodeXโ experimental wavelet codec (fourcc:SNOW) โ๏ธSony PlayStation MDEC (Motion DECoder)โ decodeXSorenson Vector Quantizer 1โ encodeX, decodeXโ fourcc:SVQ1Sorenson Vector Quantizer 3โ decodeXโ fourcc:SVQ3Sunplus JPEG (SP5X)โ decodeXโ fourcc:SP5XTechSmith Screen Capture Codecโ decodeXโ fourcc:TSCCTechSmith Screen Capture Codec 2โ decodeXโ fourcc:TSC2Theoraโ encodeE, decodeXโ encoding is supported through the external librarylibtheora๐งTiertex Limited SEQ videoโ decodeXโ the codec used in the DOS CD-ROM FlashBack game ๐น๏ธUt Videoโ encodeX, decodeXv210 QuickTime uncompressed 4:2:2 10-bitโ encodeX, decodeXv308 QuickTime uncompressed 4:4:4โ encodeX, decodeXv408 QuickTime uncompressed 4:4:4:4โ encodeX, decodeXv410 QuickTime uncompressed 4:4:4 10-bitโ encodeX, decodeXVBLE Lossless Codecโ decodeXvMix Videoโ decodeXโ fourcc:'VMX1'VMware Screen Codec / VMware Videoโ decodeXโ the codec used in videos captured by VMware ๐ฅ๏ธWestwood Studios VQA (Vector Quantized Animation) videoโ decodeXWindows Media Imageโ decodeXWindows Media Video 7โ encodeX, decodeXWindows Media Video 8โ encodeX, decodeXWindows Media Video 9โ decodeXโ and heads up bestie, it's not completely working ๐ญWing Commander III / Xanโ decodeXโ used in Wing Commander III.MVEfilesWing Commander IV / Xanโ decodeXโ used in Wing Commander IVWinnov WNV1โ decodeXWMV7โ encodeX, decodeXYAMAHA SMAFโ encodeX, decodeXPsygnosis YOP Videoโ decodeXyuv4โ encodeX, decodeXโ libquicktime uncompressed packed 4:2:0ZeroCodec Lossless Videoโ decodeXZLIBโ encodeX, decodeXโ part of LCL, and the encoder is experimental ๐งชZip Motion Blocks Videoโ encodeX, decodeXโ the encoder works only inPAL8, no cap
So real talk, here's the key to the little letters, bestie ๐:
"X" means that the feature in that column (encoding / decoding) is supported. Periodt.
"E" means that support is provided through an external library. So like, somebody else's code is doing the heavy lifting ๐ซถ
๐ง Audio Codecs ๐ง
Same energy, same grid, but for sound this time:
Name : Encoding @tab Decoding @tab Comments
8SVX exponentialโ decodeX8SVX fibonacciโ decodeXAACโ encodeEX, decodeXโ encoding is supported through the internal encoder and the external librarylibfdk-aacโจAAC+โ encodeE, decodeIXโ encoding is supported through the external librarylibfdk-aacAC-3โ encodeIX, decodeIXACELP.KELVINโ decodeXADPCM 4X Movieโ decodeXADPCM Yamaha AICAโ decodeXADPCM AmuseGraphics Movieโ decodeXADPCM Argonaut Gamesโ encodeX, decodeXADPCM CDROM XAโ decodeXADPCM Creative Technologyโ decodeXโ16 -> 4,8 -> 4,8 -> 3,8 -> 2๐ขADPCM Electronic Artsโ decodeXโ used in various EA titlesADPCM Electronic Arts Maxis CDROM XSโ decodeXโ used in Sim City 3000 ๐๏ธADPCM Electronic Arts R1โ decodeXADPCM Electronic Arts R2โ decodeXADPCM Electronic Arts R3โ decodeXADPCM Electronic Arts XASโ decodeXADPCM G.722โ encodeX, decodeXADPCM G.726โ encodeX, decodeXADPCM IMA Acorn Replayโ decodeXADPCM IMA AMVโ encodeX, decodeXโ used in AMV filesADPCM IMA Cunning Developmentsโ decodeXADPCM IMA Electronic Arts EACSโ decodeXADPCM IMA Electronic Arts SEADโ decodeXADPCM IMA Funcomโ decodeXADPCM IMA High Voltage Software ALPโ encodeX, decodeXADPCM IMA Mobiclip MOFLEXโ decodeXADPCM IMA QuickTimeโ encodeX, decodeXADPCM IMA Simon & Schuster Interactiveโ encodeX, decodeXADPCM IMA Ubisoft APMโ encodeX, decodeXADPCM IMA Loki SDL MJPEGโ decodeXADPCM IMA WAVโ encodeX, decodeXADPCM IMA Westwoodโ decodeXADPCM ISS IMAโ decodeXโ used in FunCom gamesADPCM IMA Dialogicโ decodeXADPCM IMA Duck DK3โ decodeXโ used in some Sega Saturn console games ๐ฎADPCM IMA Duck DK4โ decodeXโ same, used in some Sega Saturn console gamesADPCM IMA Radicalโ decodeXADPCM IMA Xboxโ decodeXADPCM Microsoftโ encodeX, decodeXADPCM MS IMAโ encodeX, decodeXADPCM Nintendo Gamecube AFCโ decodeXADPCM Nintendo Gamecube DTKโ decodeXADPCM Nintendo THPโ decodeXADPCM Playstationโ decodeXADPCM QT IMAโ encodeX, decodeXADPCM Sanyoโ decodeXADPCM SEGA CRI ADXโ encodeX, decodeXโ used in Sega Dreamcast gamesADPCM Shockwave Flashโ encodeX, decodeXADPCM Sound Blaster Pro 2-bitโ decodeXADPCM Sound Blaster Pro 2.6-bitโ decodeXADPCM Sound Blaster Pro 4-bitโ decodeXADPCM VIMAโ decodeXโ used in LucasArts SMUSH animations ๐จADPCM Konami XMDโ decodeXADPCM Westwood Studios IMAโ encodeX, decodeXโ used in Westwood Studios games like Command and ConquerADPCM Yamahaโ encodeX, decodeXADPCM Zorkโ decodeXAMR-NBโ encodeE, decodeXโ encoding is supported through the external librarylibopencore-amrnbAMR-WBโ encodeE, decodeXโ encoding is supported through the external librarylibvo-amrwbencAmazing Studio PAF Audioโ decodeXApple lossless audioโ encodeX, decodeXโ QuickTime fourcc'alac'๐aptXโ encodeX, decodeXโ used in Bluetooth A2DPaptX HDโ encodeX, decodeXโ used in Bluetooth A2DPATRAC1โ decodeXATRAC3โ decodeXATRAC3+โ decodeXATRAC9โ decodeXBink Audioโ decodeXโ used in Bink and Smacker files in many gamesBonk audioโ decodeXCELTโ decodeEโ decoding is supported through the external librarylibceltcodec2โ encodeE, decodeEโ en/decoding supported through the external librarylibcodec2CRI HCAโ decodeXDelphine Software International CIN audioโ decodeXโ the codec used in Delphine Software International gamesDFPWMโ encodeX, decodeXDigital Speech Standard - Standard Play mode (DSS SP)โ decodeXDiscworld II BMV Audioโ decodeXCOOKโ decodeXโ all versions except5.1are supportedDCA (DTS Coherent Acoustics)โ encodeX, decodeXโ supported extensions:XCh,XXCH,X96,XBR,XLL,LBR(partially) ๐Dolby Eโ decodeXDPCM Cuberoot-Delta-Exactโ encodeX, decodeXโ used in a few gamesDPCM Gremlinโ decodeXDPCM id RoQโ encodeX, decodeXโ used in Quake III, Jedi Knight 2 and other computer gamesDPCM Marble WADYโ decodeXDPCM Interplayโ decodeXโ used in various Interplay computer gamesDPCM Squareroot-Delta-Exactโ encodeX, decodeXโ used in various gamesDPCM Sierra Onlineโ decodeXโ used in Sierra Online game audio filesDPCM Solโ decodeXDPCM Xanโ decodeXโ used in Origin's Wing Commander IV AVI filesDPCM Xilam DERFโ decodeXDSD (Direct Stream Digital), least significant bit firstโ encodeX, decodeXDSD (Direct Stream Digital), most significant bit firstโ encodeX, decodeXDSD (Direct Stream Digital), least significant bit first, planarโ encodeX, decodeXDSD (Direct Stream Digital), most significant bit first, planarโ encodeX, decodeXDSP Group TrueSpeechโ decodeXDST (Direct Stream Transfer)โ encodeX, decodeXDV audioโ decodeXEnhanced AC-3โ encodeX, decodeXEVRC (Enhanced Variable Rate Codec)โ decodeXFLAC (Free Lossless Audio Codec)โ encodeX, decodeIX๐FTR Voiceโ decodeXG.723.1โ encodeX, decodeXG.728โ decodeXG.729โ decodeXGSMโ encodeE, decodeXโ encoding is supported through the external librarylibgsmGSM Microsoft variantโ encodeE, decodeXโ encoding is supported through the external librarylibgsmIAC (Indeo Audio Coder)โ decodeXiLBC (Internet Low Bitrate Codec)โ encodeE, decodeEXโ encoding and decoding are supported through the external librarylibilbcIMC (Intel Music Coder)โ decodeXInterplay ACMโ decodeXLC3โ encodeE, decodeEโ supported through the external libraryliblc3MACE (Macintosh Audio Compression/Expansion) 6:1โ decodeXMarian's A-pac audioโ decodeXMI-SC4 (Micronas SC-4 Audio)โ decodeXMLP (Meridian Lossless Packing)โ encodeX, decodeXโ used in DVD-Audio discs ๐ฟMonkey's Audioโ decodeXMP1 (MPEG audio layer 1)โ decodeIXMP2 (MPEG audio layer 2)โ encodeIX, decodeIXโ encoding is supported also through the external libraryTwoLAMEMP3 (MPEG audio layer 3)โ encodeE, decodeIXโ encoding is supported through the external libraryLAME, andADU MP3andMP3onMP4are also supported ๐ตMPEG-4 Audio Lossless Coding (ALS)โ decodeXMPEG-H 3D Audioโ decodeEโ decoding is supported through the external librarylibmpeghdec
okay so the audio codec list literally refuses to end and we are picking up exactly where we left off, no heading, no recap, just vibes and codecs ๐ (and yes, every single one is here, I would never do you like that)
MobiClip FastAudioโ decode only, that's it (Xon the decode side)Musepack SV7โ decode only (X)Musepack SV8โ decode only (X)Nellymoser Asaoโ both ways, encodeX/ decodeXโจOn2 AVC (Audio for Video Codec)โ decode only (X)Opusโ encodeE, decodeXโ encoding comes to you courtesy of the external librarylibopusOSQ (Original Sound Quality)โ decode only (X)PCM A-lawโ encodeX/ decodeXPCM mu-lawโ encodeX/ decodeXPCM Archimedes VIDCโ encodeX/ decodeXPCM signed 8-bit planarโ encodeX/ decodeXPCM signed 16-bit big-endian planarโ encodeX/ decodeXPCM signed 16-bit little-endian planarโ encodeX/ decodeXPCM signed 24-bit little-endian planarโ encodeX/ decodeXPCM signed 32-bit little-endian planarโ encodeX/ decodeXPCM 32-bit floating point big-endianโ encodeX/ decodeXPCM 32-bit floating point little-endianโ encodeX/ decodeXPCM 64-bit floating point big-endianโ encodeX/ decodeXPCM 64-bit floating point little-endianโ encodeX/ decodeXPCM D-Cinema audio signed 24-bitโ encodeX/ decodeXPCM signed 8-bitโ encodeX/ decodeXPCM signed 16-bit big-endianโ encodeX/ decodeXPCM signed 16-bit little-endianโ encodeX/ decodeXPCM signed 24-bit big-endianโ encodeX/ decodeXPCM signed 24-bit little-endianโ encodeX/ decodeXPCM signed 32-bit big-endianโ encodeX/ decodeXPCM signed 32-bit little-endianโ encodeX/ decodeXPCM signed 16/20/24-bit big-endian in MPEG-TSโ decode only (X)PCM unsigned 8-bitโ encodeX/ decodeXPCM unsigned 16-bit big-endianโ encodeX/ decodeXPCM unsigned 16-bit little-endianโ encodeX/ decodeXPCM unsigned 24-bit big-endianโ encodeX/ decodeXPCM unsigned 24-bit little-endianโ encodeX/ decodeXPCM unsigned 32-bit big-endianโ encodeX/ decodeXPCM unsigned 32-bit little-endianโ encodeX/ decodeXPCM SGAโ decode only (X)QCELP / PureVoiceโ decode only (X)QDesign Music Codec 1โ decode only (X)QDesign Music Codec 2โ decode only (X) โ heads up: there are still some distortions ๐ญRealAudio 1.0 (14.4K)โ encodeX/ decodeXโ the Real 14400 bit/s codecRealAudio 2.0 (28.8K)โ decode only (X) โ the Real 28800 bit/s codecRealAudio 3.0 (dnet)โ encodeIX/ decodeXโ the Real low bitrate AC-3 codecRealAudio Losslessโ decode only (X)RealAudio SIPR / ACELP.NETโ decode only (X)RK Audio (RKA)โ decode only (X)SBC (low-complexity subband codec)โ encodeX/ decodeXโ the one used in Bluetooth A2DP ๐งShortenโ decode only (X)Sierra VMD audioโ decode only (X) โ used in Sierra VMD filesSmacker audioโ decode only (X)SMPTE 302M AES3 audioโ encodeX/ decodeXSonicโ encodeX/ decodeXโ experimental codec, she's still in beta bestieSonic losslessโ encodeX/ decodeXโ also experimental codecSpeexโ encodeE/ decodeEXโ supported through the external librarylibspeexTAK (Tom's lossless Audio Kompressor)โ decode only (X)True Audio (TTA)โ encodeX/ decodeXTrueHDโ encodeX/ decodeXโ used in HD-DVD and Blu-Ray discs ๐ฟTwinVQ (VQF flavor)โ decode only (X)VIMAโ decode only (X) โ used in LucasArts SMUSH animationsViewQuest VQCโ decode only (X)Vorbisโ encodeE/ decodeXโ a native but very primitive encoder exists, so, y'know, manage expectationsVoxware MetaSoundโ decode only (X)Waveform Archiverโ decode only (X)WavPackโ encodeX/ decodeXWestwood Audio (SND1)โ decode only (X)Windows Media Audio 1โ encodeX/ decodeXWindows Media Audio 2โ encodeX/ decodeXWindows Media Audio Losslessโ decode only (X)Windows Media Audio Proโ decode only (X)Windows Media Audio Voiceโ decode only (X)Xbox Media Audio 1โ decode only (X)Xbox Media Audio 2โ decode only (X)
and the legend, because the letters mean things:
Xmeans the feature in that column (encoding / decoding) is supported ๐Emeans support is provided through an external libraryImeans an integer-only version is available too โ which keeps performance high on systems without hardware floating point support โก
๐ฌ Subtitle Formats
the columns here are muxing, demuxing, encoding and decoding โ I'm only listing the ones that get an X, so if a column isn't mentioned, it's a no ๐
3GPP Timed Textโ encodingX, decodingXAQTitleโ demuxingX, decodingXDVBโ muxingX, demuxingX, encodingX, decodingXโ all four, she ate ๐DVB teletextโ demuxingX, decodingE(external library, bestie)DVDโ muxingX, demuxingX, encodingX, decodingXJACOsubโ muxingX, demuxingX, decodingXMicroDVDโ muxingX, demuxingX, decodingXMPL2โ demuxingX, decodingXMPsub (MPlayer)โ demuxingX, decodingXPGSโ decodingX, and that's the whole personalityPJS (Phoenix)โ demuxingX, decodingXRealTextโ demuxingX, decodingXSAMIโ demuxingX, decodingXSpruce format (STL)โ demuxingX, decodingXSSA/ASSโ muxingX, demuxingX, encodingX, decodingXSubRip (SRT)โ muxingX, demuxingX, encodingX, decodingXSubViewer v1โ demuxingX, decodingXSubViewerโ demuxingX, decodingXTED Talks captionsโ demuxingX, decodingXTTMLโ muxingX, encodingXVobSub (IDX+SUB)โ demuxingX, decodingXVPlayerโ demuxingX, decodingXWebVTTโ muxingX, demuxingX, encodingX, decodingXXSUBโ encodingX, decodingXXmeans that the feature is supported โจEmeans that support is provided through an external library
๐ Network Protocols
AMQPโE(external library)fileโXFTPโXGopherโXGophersโXHLSโXHTTPโXHTTPSโX๐IcecastโXMMSHโXMMSTโXpipeโXPro-MPEG FECโXRTMPโXRTMPEโXRTMPSโXRTMPTโXRTMPTEโXRTMPTSโXRTPโXSAMBAโE(external library)SCTPโXSFTPโE(external library)TCPโXTLSโXUDPโXZMQโE(external library)Xmeans that the protocol is supported ๐Emeans that support is provided through an external library
๐๏ธ Input/Output Devices
ALSAโ inputX, outputXBKTRโ inputXcacaโ outputXDV1394โ inputXLavfi virtual deviceโ inputXLinux framebufferโ inputX, outputXJACKโ inputXLIBCDIOโ inputXLIBDC1394โ inputXOpenALโ inputXOpenGLโ outputXOSSโ inputX, outputXPulseAudioโ inputX, outputXSDLโ outputXVideo4Linux2โ inputX, outputXVfW captureโ inputXX11 grabbingโ inputXWin32 grabbingโ inputXXmeans that input/output is supported ๐ซถ
โฑ๏ธ Timecode
AVIโ readX, writeXDVโ readX, writeXGXFโ readX, writeXMOVโ readX, writeXMPEG1/2โ readX, writeXMXFโ readX, writeX
๐ SEE ALSO
ffplay(1), ffmpeg(1), ffprobe(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)
like, the whole squad is here ๐
๐ AUTHORS
The FFmpeg developers.
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 it, we made it to the end of the whole thing ๐ญ๐๐ every last PCM variant, every subtitle format, every protocol โ all of it, no skips, no cap. the footer on this page just reads FFPLAY-ALL(1), which is the only credit she needs honestly. go watch something now bestie, you've earned it ๐โจ๐ฆ
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
- ๐ girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms