GStreamer(1)

💖 GStreamer 💖 (that's the manual name bestie, section 1, general commands)

okay so welcome to the gst-launch-1.0 page, aka the place where pipelines get built and run and your terminal gets very loud. buckle up. 🎀

---

✨ NAME ✨

gst-launch-1.0 — build and run a GStreamer pipeline 💅

---

✨ SYNOPSIS ✨

gst-launch-1.0 [OPTION...] PIPELINE-DESCRIPTION

---

✨ DESCRIPTION ✨

So gst-launch-1.0 is the tool that builds and runs basic GStreamer pipelines. that's the whole vibe. 🦋

In its simple form, a PIPELINE-DESCRIPTION is just a list of elements, separated by exclamation marks (!). You can stick properties onto elements like property=value. And you can also set a "preset" using the @preset=<preset name> syntax. cute right?

For the full deets on every possible PIPELINE-DESCRIPTION, scroll down to the pipeline description section below, or go read the GStreamer documentation.

⚠️ bestie listen. gst-launch-1.0 is primarily a debugging tool for developers and users. You should not build applications on top of it. fr fr. If you want an application, write a little python script or Rust application (or literally whatever other programming language you prefer) and use the gst_parse_launch() function of the GStreamer API — that's the easy way to construct pipelines from pipeline descriptions. periodt. 👑

---

✨ OPTIONS ✨

gst-launch-1.0 accepts the following options, and yes we're listing all of them:

• --help — prints the help synopsis and the available FLAGS
• -v, --verbose — output status information and property notifications 📢
• -q, --quiet — do NOT print any progress information (silent mode, mysterious, iconic)
• -m, --messages — output messages posted on the pipeline's bus
• -t, --tags — output tags (also known as metadata)
• -e, --eos-on-shutdown — force an EOS event on sources before shutting the pipeline down. This is useful to make sure muxers create readable files when a muxing pipeline is shut down forcefully via Control-C — especially in the case of mp4mux and qtmux, where the created file will be unreadable if the file has not been finalised properly. 💀 so yeah, use it.
• -f, --no-fault — do not install a segfault handler
• --no-position — do not print the current position of the pipeline. If this option is unspecified, the position will be printed when stdout is a TTY. To enable printing position when stdout is not a TTY, use the --force-position option.
• --force-position — allow printing the current position of the pipeline even if stdout is not a TTY. This option has no effect if the --no-position option is specified.

---

💜 GSTREAMER OPTIONS 💜

gst-launch-1.0 also accepts these options that are common to all GStreamer applications. shared slay. 🌈

• --gst-version — prints the version string of the GStreamer core library.
• --gst-fatal-warnings — causes GStreamer to abort if a warning message occurs. This is equivalent to setting the environment variable G_DEBUG to 'fatal_warnings' (see the environment variables section below for more info). 😭 it really will just abort.
• --gst-debug=STRING — a comma separated list of category_name:level pairs to specify debugging levels for each category. Level is in the range 0-9, where 0 will show no messages and 9 will show all messages. The wildcard * can be used to match category names. Note that the order of categories and levels is important — wildcards at the end may override levels set earlier. The log levels are: 1=ERROR, 2=WARNING, 3=FIXME, 4=INFO, 5=DEBUG, 6=LOG, 7=TRACE, 9=MEMDUMP. Since GStreamer 1.2 you can also use the debug level names, e.g. --gst-debug=*sink:LOG. A full description of the various debug levels lives in the GStreamer core library API documentation, in the "Running GStreamer Applications" section.

Use --gst-debug-help to show category names.

Example: GST_CAT:5,GST_ELEMENT_*:3,oggdemux:5

• --gst-debug-level=LEVEL — sets the threshold for printing debugging messages. A higher level will print more messages. The useful range is 0-9, with the default being 0. Level 6 (LOG level) will show all information that is usually required for debugging purposes. Higher levels are only useful in very specific cases. See above for the full list of levels. 👀
• --gst-debug-no-color — GStreamer normally prints debugging messages so that the messages are color-coded when printed to a terminal that handles ANSI escape sequences. Using this option causes GStreamer to print messages without color. Setting the GST_DEBUG_NO_COLOR environment variable will achieve the same thing.
• --gst-debug-color-mode — GStreamer normally prints debugging messages so that the messages are color-coded when printed to a terminal that handles ANSI escape sequences (on *nix), or uses the W32 console API to color the messages printed into a console (on W32). Using this option causes GStreamer to print messages without color ('off' or 'disable'), print messages with default colors ('on' or 'auto'), or print messages using ANSI escape sequences for coloring ('unix'). Setting the GST_DEBUG_COLOR_MODE environment variable will achieve the same thing. 🌈
• --gst-debug-disable — disables debugging. gone. bye. 🙈
• --gst-debug-help — prints a list of available debug categories and their default debugging level.
• --gst-plugin-path=PATH — add directories separated with ':' to the plugin search path
• --gst-plugin-load=PLUGINS — preload plugins specified in a comma-separated list. Another way to specify plugins to preload is to use the environment variable GST_PLUGIN_PATH

---

✨ PIPELINE DESCRIPTION ✨

A pipeline consists of elements and links. Elements can be put into bins of different sorts. Elements, links and bins can be specified in a pipeline description in any order. yes queen, any order you want. 🫶

🌸 Elements 🌸

ELEMENTTYPE [PROPERTY1 ...]

Creates an element of type ELEMENTTYPE and sets the PROPERTIES.

🌸 Properties 🌸

PROPERTY=VALUE ...

Sets the property to the specified value. You can use gst-inspect-1.0(1) to find out about properties and the allowed values of different elements. Enumeration properties can be set by name, nick or value. (three ways, so many options, obsessed.)

🌸 Presets 🌸

@preset=<preset name> ...

Sets the preset on the element. you can use gst-inspect-1.0(1) to find out what presets are available for a specific element. 💅

🌸 Bins 🌸

[BINTYPE.] ( [PROPERTY1 ...] PIPELINE-DESCRIPTION )

Specifies that a bin of type BINTYPE is created and the given properties are set. Every element between the braces gets put into the bin. Please note the dot that has to be used after the BINTYPE. ⚠️

You will almost never need this functionality — it is only really useful for applications using the gst_launch_parse() API with 'bin' as bintype. That way it's possible to build partial pipelines instead of a full-fledged top-level pipeline.

🌸 Links 🌸

[[SRCELEMENT].[PAD1,...]] ! [[SINKELEMENT].[PAD1,...]]
[[SRCELEMENT].[PAD1,...]] ! CAPS ! [[SINKELEMENT].[PAD1,...]]
[[SRCELEMENT].[PAD1,...]] : [[SINKELEMENT].[PAD1,...]]
[[SRCELEMENT].[PAD1,...]] : CAPS : [[SINKELEMENT].[PAD1,...]]

Links the element with name SRCELEMENT to the element with name SINKELEMENT, using the caps specified in CAPS as a filter. Names can be set on elements with the name property. If the name is omitted, the element that was specified directly in front of or after the link is used. This works across bins. 🦋

If a padname is given, the link is done with these pads. If no pad names are given, all possibilities are tried and a matching pad is used. If multiple padnames are given, both sides must have the same number of pads specified, and multiple links are done in the given order.

So the simplest link is a simple exclamation mark, which links the element to the left of it to the element to the right of it. ✨

Linking using the : operator attempts to link all possible pads between the elements.

🌸 Caps 🌸

MEDIATYPE [, PROPERTY[, PROPERTY ...]]] [; CAPS[; CAPS ...]]

Creates a capability with the given media type and optionally with given properties. The media type can be escaped using " or '. If you want to chain caps, you can add more caps in the same format afterwards. chain chain chain ⛓️

🌸 Properties 🌸

NAME=[(TYPE)]VALUE
in lists and ranges: [(TYPE)]VALUE

Sets the requested property in capabilities. The name is an alphanumeric value and the type can have the following case-insensitive values:

• i or int for integer values or ranges
• f or float for float values or ranges
• b, bool or boolean for boolean values
• s, str or string for strings
• fraction for fractions (framerate, pixel-aspect-ratio)
• l or list for lists

If no type was given, the following order is tried: integer, float, boolean, string.

Integer values must be parsable by strtol(), floats by strtod(). FOURCC values may either be integers or strings. Boolean values are (case insensitive) yes, no, true or false, and may — like strings — be escaped with " or '.

Ranges are in this format:

[ VALUE, VALUE ]

Lists use this format:

{ VALUE [, VALUE ...] }

and that's the end of part 1 bestie, there's more coming so don't go anywhere 💖

🎬 PIPELINE EXAMPLES 🎬

okay bestie, this is the fun part — actual pipelines you can copy-paste and watch do stuff. 💖

All of these assume you actually have the right plug-ins installed, so if something yells at you, that's the vibe check failing, not you. 🫶

About sinks, real quick: "pulsesink" can be swapped for another audio output plug-in, like "alsasink", "osxaudiosink" or "wasapisink". Same energy for "xvimagesink" — you can trade it for "d3dvideosink", "ximagesink", "glimagesink", or "osxvideosink". ✨

⚠️ lowkey important: different sinks might accept different formats, and even the same sink might accept different formats on different machines. so you might need to add converter elements like audioconvert and audioresample (for audio) or videoconvertscale (for video) right in front of the sink to make things work. no cap.

---

🎧 Audio playback 🎧

Note: For audio/video playback it's best to use the playbin3 or uridecodebin3 elements — these are just example pipelines, bestie, don't come for me. 💅

Play the mp3 music file "music.mp3" using a libmpg123-based plug-in and output to an Pulseaudio device

gst-launch-1.0 filesrc location=music.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! audioresample ! pulsesink

Play an Ogg Vorbis format file

gst-launch-1.0 filesrc location=music.ogg ! oggdemux ! vorbisdec ! audioconvert ! audioresample ! pulsesink

Play an mp3 file or an http stream using GIO

gst-launch-1.0 giosrc location=music.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! pulsesink
gst-launch-1.0 giosrc location=http://domain.com/music.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! audioresample ! pulsesink

Use GIO to play an mp3 file located on an SMB server

gst-launch-1.0 giosrc location=smb://computer/music.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! audioresample ! pulsesink

---

🎀 Format conversion 🎀

Convert an mp3 music file to an Ogg Vorbis file

gst-launch-1.0 filesrc location=music.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! vorbisenc ! oggmux ! filesink location=music.ogg

Convert to the FLAC format

gst-launch-1.0 filesrc location=music.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! flacenc ! filesink location=test.flac

---

🦋 Other 🦋

Plays a .WAV file that contains raw audio data (PCM).

gst-launch-1.0 filesrc location=music.wav ! wavparse ! audioconvert ! audioresample ! pulsesink

Convert a .WAV file containing raw audio data into an Ogg Vorbis or mp3 file

gst-launch-1.0 filesrc location=music.wav ! wavparse ! audioconvert ! vorbisenc ! oggmux ! filesink location=music.ogg
gst-launch-1.0 filesrc location=music.wav ! wavparse ! audioconvert ! lamemp3enc ! xingmux ! id3v2mux ! filesink location=music.mp3

Rips all tracks from compact disc and convert them into a single mp3 file

gst-launch-1.0 cdparanoiasrc mode=continuous ! audioconvert ! lamemp3enc ! mpegaudioparse ! xingmux ! id3v2mux ! filesink location=cd.mp3

Rips track 5 from the CD and converts it into a single mp3 file

gst-launch-1.0 cdparanoiasrc track=5 ! audioconvert ! lamemp3enc ! mpegaudioparse ! xingmux ! id3v2mux ! filesink location=track5.mp3

Using gst-inspect-1.0(1), it is possible to discover settings like the above for cdparanoiasrc that will tell it to rip the entire cd or only tracks of it. 👀

Alternatively, you can use an URI and gst-launch-1.0 will find an element (such as cdparanoia) that supports that protocol for you, e.g.:

gst-launch-1.0 cdda://5 ! lamemp3enc vbr=new vbr-quality=6 ! filesink location=track5.mp3

Records sound from your audio input and encodes it into an ogg file

gst-launch-1.0 pulsesrc ! audioconvert ! vorbisenc ! oggmux ! filesink location=input.ogg

---

🌈 Video 🌈

Note: For audio/video playback it's best to use the playbin3 or uridecodebin3 elements — again, these are just example pipelines. 💅

Display only the video portion of an MPEG-2 PS video file, outputting to an X display window

gst-launch-1.0 filesrc location=JB_FF9_TheGravityOfLove.mpg ! mpegdemux ! mpegvideoparse ! mpeg2dec ! videoconvert ! xvimagesink

Display the video portion of a .vob file (used on DVDs), outputting to an SDL window

gst-launch-1.0 filesrc location=/flflfj.vob ! dvddemux ! mpegvideoparse ! mpeg2dec ! videoconvert ! sdlvideosink

Play both video and audio portions of an MPEG movie

gst-launch-1.0 filesrc location=movie.mpg ! dvddemux name=demuxer  demuxer. ! queue ! mpegvideoparse ! mpeg2dec ! videoconvert ! sdlvideosink  demuxer. ! queue ! mpegaudioparse ! mpg123audiodec ! audioconvert ! audioresample ! pulsesink

Play an AVI movie with an external text subtitle stream

This example also shows how to refer to specific pads by name if an element (here: textoverlay) has multiple sink or source pads. 🎯

gst-launch-1.0 textoverlay name=overlay ! videoconvert ! videoscale !  autovideosink   filesrc location=movie.avi ! decodebin3 ! videoconvert ! overlay.video_sink   filesrc location=movie.srt ! subparse ! overlay.text_sink

Play an AVI movie with an external text subtitle stream using playbin3

gst-launch-1.0 playbin3 uri=file:///path/to/movie.avi suburi=file:///path/to/movie.srt

---

🛰️ Network streaming 🛰️

Stream video using RTP and network elements. it's giving network girlie ✨

This command would be run on the transmitter:

gst-launch-1.0 v4l2src ! queue ! videoconvert ! x264enc tune=zerolatency key-int-max=15 ! video/x-h264,profile=main !rtph264pay pt=96 config-interval=-1 ! udpsink host=192.168.1.1 port=5000

Use this command on the receiver:

gst-launch-1.0 udpsrc port=5000 ! application/x-rtp, clock-rate=90000,payload=96 ! rtpjitterbuffer ! rtph264depay ! h264parse ! avdec_h264 ! videoconvert ! xvimagesink

---

🩺 Diagnostic 🩺

Generate a null stream and ignore it (and print out details).

gst-launch-1.0 -v fakesrc num-buffers=16 ! fakesink silent=false

Generate a pure sine tone to test the audio output

gst-launch-1.0 audiotestsrc ! audioconvert ! audioresample ! pulsesink

Generate a familiar test pattern to test the video output

gst-launch-1.0 videotestsrc ! xvimagesink
gst-launch-1.0 videotestsrc ! ximagesink

---

🪄 Automatic linking 🪄

You can use the decodebin element to automatically select the right elements to get a working pipeline. honestly iconic, it does the thinking for you 💅

Play any supported audio format

gst-launch-1.0 filesrc location=musicfile ! decodebin3 ! audioconvert ! audioresample ! pulsesink

Play any supported video format with video and audio output. Threads are used automatically. To make this even easier, you can use the playbin element:

gst-launch-1.0 filesrc location=videofile ! decodebin3 name=decoder decoder. ! queue ! audioconvert ! audioresample ! pulsesink decoder. !  videoconvert ! xvimagesink
gst-launch-1.0 playbin3 uri=file:///home/joe/foo.avi
gst-launch-1.0 playbin3 uri=https://gstreamer.freedesktop.org/data/media/sintel_trailer-480p.webm

---

🔮 Filtered connections 🔮

These examples show you how to use filtered caps. so fancy, so precise 🎀

Show a test image and use the YUY2 or YV12 video format for this.

gst-launch-1.0 videotestsrc ! 'video/x-raw,format=YUY2;video/x-raw,format=YV12' ! xvimagesink
gst-launch-1.0 v4l2src ! image/jpeg ! queue ! decodebin3 ! videoconvert ! autovideosink

Record audio and write it to a .wav file. Force usage of signed 16 to 32 bit samples and a sample rate between 32kHz and 64KHz.

gst-launch-1.0 pulsesrc ! 'audio/x-raw,rate=[32000,64000],format={S16LE,S24LE,S32LE}' ! wavenc ! filesink location=recording.wav

🌈 ENVIRONMENT VARIABLES 🌈

okay bestie, these are the env vars that make GStreamer do its little tricks. set them in your shell and watch the magic, no cap.

• GST_DEBUG — comma-separated list of debug categories and levels, like GST_DEBUG=totem:4,typefind:5. The wildcard '*' is allowed as part of debug category names, e.g. GST_DEBUG=*sink:6,*audio*:6. Since 1.2.0 it is also possible to specify the log level by name: 1=ERROR, 2=WARN, 3=FIXME, 4=INFO, 5=DEBUG, 6=LOG, 7=TRACE, 9=MEMDUMP (example: GST_DEBUG=*audio*:LOG). obsessed with a good debug log tbh 💖
• GST_DEBUG_NO_COLOR — when this environment variable is set, coloured debug output is disabled. no rainbow debug, sad but sometimes necessary
• GST_DEBUG_DUMP_DOT_DIR — when set to a filesystem path, store 'dot' files of pipeline graphs there. These can then later be converted into an image using the 'dot' utility from the graphviz set of tools, like this:

dot foo.dot -Tsvg -o foo.svg

png or jpg are also possible as output format. There is also a utility called 'xdot' which allows you to view the .dot file directly without converting it first. When the pipeline changes state through NULL to PLAYING and back to NULL, a dot file is generated on each state change. To write a snapshot of the pipeline state, send a SIGHUP to the process or use the pipeline_snapshot tracer from the GStreamer Rust plugins. dot files are giving graph girlie energy ✨

• GST_REGISTRY — path of the plugin registry file. Default is ~/.cache/gstreamer-1.0/registry-CPU.bin where CPU is the machine/cpu type GStreamer was compiled for, e.g. 'x86_64', etc. (check the output of "uname -i" and "uname -m" for details). registry lore 💅
• GST_REGISTRY_UPDATE — set to "no" to force GStreamer to assume that no plugins have changed, been added or been removed. This will make GStreamer skip the initial check whether a rebuild of the registry cache is required or not. This may be useful in embedded environments where the installed plugins never change.

Do not use this option in any other setup. like fr fr, don't.

• GST_PLUGIN_PATH — specifies a list of directories to scan for additional plugins. These take precedence over the system plugins. extra plugins first, periodt
• GST_PLUGIN_SYSTEM_PATH — specifies a list of plugins that are always loaded by default. If not set, this defaults to the system-installed path, and the plugins installed in the user's home directory. default plugin vibes 🦋
• GST_DEBUG_FILE — set this variable to a file path to redirect all GStreamer debug messages to this file. If left unset, debug messages will be output to the standard error output. log to file instead of screaming into stderr 😭
• ORC_CODE — useful Orc environment variable. Set ORC_CODE=debug to enable debuggers such as gdb to create useful backtraces from Orc-generated code. Set ORC_CODE=backup or ORC_CODE=emulate if you suspect Orc's SIMD code generator is producing incorrect code. (Quite a few important GStreamer plugins like videotestsrc, audioconvert or audioresample use Orc). Orc said slay but sometimes it's sus
• G_DEBUG — useful GLib environment variable. Set G_DEBUG=fatal_warnings to make GStreamer programs abort when a critical warning such as an assertion failure occurs. This is useful if you want to find out which part of the code caused that warning to be triggered and under what circumstances. Simply set G_DEBUG as mentioned above and run the program in gdb (or let it core dump). Then get a stack trace in the usual way. fatal warnings = main character debugging arc 💅

---

📁 FILES 📁

• ~/.cache/gstreamer-1.0/registry-*.bin — the plugin cache; can be deleted at any time, will be re-created automatically when it does not exist yet or plugins change. Based on XDG_CACHE_DIR, so may be in a different location than the one suggested. delete it, it'll come back, it's fine 🫶

---

👀 SEE ALSO 👀

ok bestie, go read these too:

• gst-inspect-1.0(1)
• gst-launch-1.0(1)

---

👑 AUTHOR 👑

The GStreamer team at http://gstreamer.freedesktop.org/

no cap, they built this whole thing. icons only 💖

---

💖 that's the whole GStreamer(1) page, source/version GStreamer(1), dated May 2007 — bye bestie, go make pipelines! 💅