--- name: "gst-launch-0.8" section: "1" platform: "linux" package: "gstreamer0.8-tools" version: "0.8.12-2" release: "Debian 4.0 (Etch)" platforms: ["linux"] url: "https://new.carta.tech/gst-launch-0.8" --- # gst-launch-0.8(1) build and run a GStreamer pipeline ## NAME gst-launch-0.8 - build and run a GStreamer pipeline ## SYNOPSIS **gst-launch-0.8** *\[OPTION...\]* PIPELINE-DESCRIPTION ## DESCRIPTION *gst-launch-0.8* is a tool that builds and runs basic *GStreamer* pipelines. In simple form, a PIPELINE-DESCRIPTION is a list of elements separated by exclamation marks (!). Properties may be appended to elements, in the form *property=value*. For a complete description of possible PIPELINE-DESCRIPTIONS see above under *pipeline description* or the GStreamer documentation. ## OPTIONS *gst-launch-0.8* accepts the following options: - **--help** Print help synopsis and available FLAGS - **-i, --iterations=N** Stop processing after N iterations. - **-v, --silent** Output status information - **-XTYPE, --exclude=TYPE,** Do not output status information of TYPE - **-oFILE, --output=FILE** Save XML representation of pipeline to FILE and exit - **-f, --no\_fault** Do not install a fault handler - **-T, --trace** Print memory allocation traces. The feature must be enabled at compile time to work. - **-t, --tags** Print tags found in the streams, if any. - **--version** Show version information and exit. ## GSTREAMER OPTIONS *gst-launch-0.8* also accepts the following options that are common to all GStreamer applications: - **--gst-version** Prints the version string of the *GStreamer* core library. - **--gst-fatal-warnings** Causes *GStreamer* to abort if a warning message occurs. - **--gst-debug=STRING** A colon separated list of category\_name=level pairs to specify debugging levels for each category. Level is in the range 0-5 where 0 will show no messages, and 5 will show all messages. The wildcard \* can be used to match category names. Use --gst-debug-help to show category names Example: GST\_CAT=5:GST\_ELEMENT\_\*=3 - **--gst-debug-level=LEVEL** Sets the threshold for printing debugging messages. A higher level will print more messages. The useful range is 0-5, with the default being 0. - **--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. - **--gst-disable-debug** Disables debugging. - **--gst-debug-help** Prints a list of available debug categories and their default debugging level. - **--gst-disable-cpu-opt** *GStreamer* normally automatically detects the capabilities of the current CPU and selects the optimal implementation for some functions. Using this flag disables detection, which is useful for debugging. - **--gst-plugin-spew** *GStreamer* info flags to set Enable printout of errors while loading *GStreamer* plugins - **--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 - **--gst-scheduler=SCHEDULER** Use SCHEDULER as the default scheduler - **--gst-registry=REGISTRY** Use the file REGISTRY as registry instead of the default ## PIPELINE DESCRIPTION A pipeline consists *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. **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) to find out about properties and allowed values of different elements.\ Enumeration properties can be set by name, nick or value. **Bins** *\[BINTYPE.\]* ( *\[PROPERTY1 ...\]* PIPELINE-DESCRIPTION )\ { *\[PROPERTY1 ...\]* PIPELINE-DESCRIPTION } Specifies that a bin of type BINTYPE is created and the given properties are set. Every element between the braces is put into the bin. Using curly braces (second line) is a short cut for using the first line and "thread" as the BINTYPE.\ Please not the dot that has to be used after the BINTYPE. **Links** *\[\[SRCELEMENT\].\[PAD1,...\]\]* ! *\[\[SINKELEMENT\].\[PAD1,...\]\]* *\[\[SRCELEMENT\].\[PAD1,...\]\]* ! 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, that links the element to the left of it to the element right of it.\ Note that when specifying either pads or element names you have to include the dot or your syntax will be misinterpreted. This is a change to the old syntax used up to version 0.6 that allowed omitting the dot when only specifying a padname. **Caps** MIMETYPE *\[, PROPERTY\[, PROPERTY ...\]\]\]* *\[; CAPS\[; CAPS ...\]\]* Creates a capability with the given mimetype and optionally with given properties. The mimetype can be escaped using " or '. If you want to chain caps, you can add more caps in the same format afterwards. **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\ \- **4** or **fourcc** for FOURCC values\ \- **b**, **bool** or **boolean** for boolean values\ \- **s**, **str** or **string** for strings\ \- **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: \[ PROPERTY, PROPERTY \]\ Lists use this format: ( PROPERTY *\[, PROPERTY ...\]* ) ## PIPELINE CONTROL A pipeline can be controlled by signals. SIGUSR2 will stop the pipeline (GST\_STATE\_NULL); SIGUSR1 will put it back to play (GST\_STATE\_PLAYING). By default, the pipeline will start in the playing state.\ There are currently no signals defined to go into the ready or pause (GST\_STATE\_READY and GST\_STATE\_PAUSED) state explicitly. ## PIPELINE EXAMPLES The examples below assume that you have the correct plug-ins available. In general, "osssink" can be substituted with another audio output plug-in such as "esdsink", "alsasink", or "artsdsink". Likewise, "xvideosink" can be substituted with "sdlvideosink" or "aasink". **Audio playback** **gst-launch-0.8 filesrc location=music.mp3 ! mad ! osssink**\ Play the mp3 music file "music.mp3" using a libmad-based plug-in and output to an OSS device **gst-launch-0.8 filesrc location=music.ogg ! oggdemux ! vorbisdec ! audioconvert ! osssink**\ Play an Ogg Vorbis format file **gst-launch-0.8 gnomevfssrc location=music.mp3 ! mad ! osssink**\ **gst-launch-0.8 gnomevfssrc location=http://domain.com/music.mp3 ! mad ! osssink**\ Play an mp3 file or an http stream using GNOME-VFS **gst-launch-0.8 gnomevfssrc location=smb://computer/music.mp3 ! mad ! osssink**\ Use GNOME-VFS to play an mp3 file located on an SMB server **Format conversion** **gst-launch-0.8 filesrc location=music.mp3 ! mad ! audioscale ! audioconvert ! rawvorbisenc ! oggmux ! filesink location=music.ogg**\ Convert an mp3 music file to an Ogg Vorbis file **gst-launch-0.8 filesrc location=music.mp3 ! mad ! flacenc ! filesink location=test.flac**\ Convert to the FLAC format **Other** **gst-launch-0.8 filesrc location=music.wav ! wavparse ! osssink**\ Plays a .WAV file **gst-launch-0.8 filesrc location=music.wav ! wavparse ! audioconvert ! rawvorbisenc ! filesink location=music.ogg**\ **gst-launch-0.8 filesrc location=music.wav ! wavparse ! mpegaudio ! filesink location=music.mp3**\ Convert a .WAV file into Ogg Vorbis (or mp3) file Alternatively, if you have lame installed (and have the lame plug-in), you can substitute lame for mpegaudio in the previous example. It gives better results than mpegaudio. **gst-launch-0.8 cdparanoia ! mpegaudio ! filesink location=cd.mp3**\ Rip all tracks from compact disc and convert them into a single mp3 file Using **gst-inspect**(1), it is possible to discover settings for cdparanoia that will tell it to rip individual tracks. **gst-launch-0.8 osssrc ! audioconvert ! rawvorbisenc ! filesink location=input.ogg**\ Record sound from your audio input and encode it into an ogg file **Video** **gst-launch-0.8 filesrc location=JB\_FF9\_TheGravityOfLove.mpg ! mpegdemux ! mpeg2dec ! xvideosink**\ Display only the video portion of an MPEG-1 video file, outputting to an X display window **gst-launch-0.8 filesrc location=/flflfj.vob ! mpegdemux ! mpeg2dec ! sdlvideosink**\ Display the video portion of a .vob file (used on DVDs), outputting to an SDL window **gst-launch-0.8 filesrc location=movie.mpg ! mpegdemux name=demuxer ! mpeg2dec ! sdlvideosink demuxer. ! mad ! osssink**\ Play both video and audio portions of an MPEG movie **gst-launch-0.8 filesrc location=movie.mpg ! mpegdemux name=demuxer ! { queue ! mpeg2dec ! sdlvideosink } { demuxer. ! queue ! mad ! osssink }**\ Use threaded output to improve synchronization and smoothness. Threads require queues for buffering on thread boundaries **gst-launch-0.8 filesrc location=movie.avi ! avidemux name=demuxer ! { queue ! ffdecall ! sdlvideosink } { demuxer. ! queue ! mad ! osssink }**\ Play an AVI movie **Network streaming** An MPEG-1 system stream can be streamed via RTP from one machine to another. **gst-launch-0.8 rtprecv media\_type=mpeg1\_sys ! mpegdemux name=demuxer ! { queue ! mpeg2dec ! xvideosink } { demuxer. ! queue ! mad ! osssink }**\ Use this command on the receiver **gst-launch-0.8 filesrc location=mpeg1system.mpeg ! mpegparse ! rtpsend ip=IPorHostname**\ This command would be run on the transmitter **Diagnostic** **gst-launch-0.8 fakesrc ! fakesink**\ Generate a null stream and ignore it **gst-launch-0.8 sinesrc ! osssink**\ Generate a pure tone to test the audio output **gst-launch-0.8 videotestsrc ! xvideosink**\ Generate a familiar test pattern to test the video output **Automatic linking** You can use the spider element to automatically select the right elements to get a working pipeline. **gst-launch-0.8 filesrc location=musicfile ! spider ! osssink**\ Play any supported audio format **gst-launch-0.8 filesrc location=videofile ! spider name=spider ! osssink spider. ! xvideosink**\ **gst-launch-0.8 filesrc location=videofile ! spider name=spider ! { queue ! osssink } { spider. ! queue ! xvideosink }**\ Play any supported video format with video and audio output. The second pipeline uses threaded output. **Filtered connections** These examples show you how to use filtered caps. **gst-launch-0.8 videotestsrc ! video/raw, format:fourcc=YUY2; video/raw, format:fourcc=YV12 ! xvideosink**\ Show a test image and use the YUY2 or YV12 video format for this. **gst-launch-0.8 osssrc ! "audio/raw", format=int, width=\[16, 32\], depth=(16, 24, 32), signed=TRUE ! osssink**\ Playback currently recorded audio. Force usage of signed 16 to 32 bit samples. ## SEE ALSO [**gst-complete-0.8**(1)](/gst-complete-0.8/1.md), [**gst-register-0.8**(1)](/gst-register-0.8/1.md), [**gst-inspect-0.8**(1)](/gst-inspect-0.8/1.md) ## AUTHOR The GStreamer team at http://gstreamer.net/