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Updated: Thursday, March 14, 2019

gst-launch-1.0 (1)


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




GStreamer(1)                General Commands Manual               GStreamer(1)

       gst-launch - build and run a GStreamer pipeline

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

       gst-launch 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 the
       section pipeline description below or consult the GStreamer  documenta-

       Please  note that gst-launch is primarily a debugging tool for develop-
       ers and users. You should not build applications  on  top  of  it.  For
       applications,  use the gst_parse_launch() function of the GStreamer API
       as an easy way to construct pipelines from pipeline descriptions.

       gst-launch accepts the following options:

       --help  Print help synopsis and available FLAGS

       -v, --verbose
               Output status information and property notifications

       -q, --quiet
               Do not print any progress information

       -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.

       -i, --index
               Gather and print index statistics. This is  mostly  useful  for
               playback or recording pipelines.

       -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.

              gst-launch also accepts the following options that are common to
              all GStreamer applications:

               Prints the version string of the GStreamer core library.

               Causes  GStreamer to abort if a warning message occurs. This is
               equivalent to  setting  the  environment  variable  G_DEBUG  to
               'fatal_warnings'  (see  the section environment variables below
               for further information).

               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 one can also use the debug level
               names, e.g. --gst-debug=*sink:LOG. A full  description  of  the
               various debug levels can be found in the GStreamer core library
               API documentation, in the "Running GStreamer Applications" sec-

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

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

               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 informa-
               tion that is usually required for  debugging  purposes.  Higher
               levels  are  only  useful in very specific cases. See above for
               the full list of levels.

               GStreamer normally prints debugging messages so that  the  mes-
               sages  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.

               GStreamer normally prints debugging messages so that  the  mes-
               sages  are  color-coded when printed to a terminal that handles
               ANSI escape sequences (on *nix), or uses  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 col-
               oring  ('unix').  Setting  the GST_DEBUG_COLOR_MODE environment
               variable will achieve the same thing.

               Disables debugging.

               Prints a list of available debug categories and  their  default
               debugging level.

               GStreamer  info  flags  to  set Enable printout of errors while
               loading GStreamer plugins

               Add directories separated with ':' to the plugin search path

               Preload plugins specified in a  comma-separated  list.  Another
               way  to  specify  plugins  to preload is to use the environment
               variable GST_PLUGIN_PATH

       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.



       Creates an element of type ELEMENTTYPE and sets the PROPERTIES.



       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.



       Specifies  that  a bin of type BINTYPE is created and the given proper-
       ties are set. Every element between the braces is  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 is possible to build partial pipelines instead of  a  full-
       fledged top-level pipeline.


       [[SRCELEMENT].[PAD1,...]]   !   [[SINKELEMENT].[PAD1,...]]    [[SRCELE-
       MENT].[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  ele-
       ment to the left of it to the element right of it.


       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 after-


       in lists and ranges: [(TYPE)]VALUE

       Sets the requested property in capabilities. The name  is  an  alphanu-
       meric  value  and the type can have the following case-insensitive val-
       - 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 ...] }

       The examples below assume that you have the correct plug-ins available.
       In  general,  "pulsesink"  can be substituted with another audio output
       plug-in such as "alsasink" or  "osxaudiosink"  Likewise,  "xvimagesink"
       can be substituted with "ximagesink", "glimagesink", or "osxvideosink".
       Keep in mind though that 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 videoconvert (for video) in front of
       the sink to make things work.

       Audio playback

               gst-launch filesrc location=music.mp3 ! mad  !  audioconvert  !
       audioresample ! pulsesink
       Play  the  mp3  music file "music.mp3" using a libmad-based plug-in and
       output to an Pulseaudio device

               gst-launch filesrc location=music.ogg ! oggdemux ! vorbisdec  !
       audioconvert ! audioresample ! pulsesink
       Play an Ogg Vorbis format file

               gst-launch  giosrc  location=music.mp3 ! mpegaudioparse ! mad !
               gst-launch giosrc location=http://domain.com/music.mp3  !  mpe-
       gaudioparse ! mad ! audioconvert ! audioresample ! pulsesink
       Play an mp3 file or an http stream using GIO

               gst-launch  giosrc  location=smb://computer/music.mp3 ! mpegau-
       dioparse ! mad ! audioconvert ! audioresample ! pulsesink
       Use GIO to play an mp3 file located on an SMB server

       Format conversion

               gst-launch filesrc location=music.mp3 ! mpegaudioparse ! mad  !
       audioconvert ! vorbisenc ! oggmux ! filesink location=music.ogg
       Convert an mp3 music file to an Ogg Vorbis file

               gst-launch  filesrc location=music.mp3 ! mpegaudioparse ! mad !
       audioconvert ! flacenc ! filesink location=test.flac
       Convert to the FLAC format


               gst-launch filesrc location=music.wav ! wavparse ! audioconvert
       ! audioresample ! pulsesink
       Plays a .WAV file that contains raw audio data (PCM).

               gst-launch filesrc location=music.wav ! wavparse ! audioconvert
       ! vorbisenc ! oggmux ! filesink location=music.ogg
               gst-launch filesrc location=music.wav ! wavparse ! audioconvert
       ! lame ! filesink location=music.mp3
       Convert a .WAV file containing raw audio data into an Ogg Vorbis or mp3

               gst-launch cdparanoiasrc mode=continuous ! audioconvert !  lame
       ! mpegaudioparse ! id3v2mux ! filesink location=cd.mp3
       rips  all  tracks  from compact disc and convert them into a single mp3

               gst-launch cdparanoiasrc track=5 ! audioconvert ! lame  !  mpe-
       gaudioparse ! id3v2mux ! filesink location=track5.mp3
       rips track 5 from the CD and converts it into a single mp3 file

       Using  gst-inspect(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  cdda://5  !  lame  vbr=new  vbr-quality=6 ! filesink

               gst-launch pulsesrc !  audioconvert  !  vorbisenc  !  oggmux  !
       filesink location=input.ogg
       records sound from your audio input and encodes it into an ogg file


               gst-launch  filesrc location=JB_FF9_TheGravityOfLove.mpg ! dvd-
       demux ! mpegvideoparse ! mpeg2dec ! xvimagesink
       Display only the video portion of an MPEG-1 video file,  outputting  to
       an X display window

               gst-launch    filesrc   location=/flflfj.vob   !   dvddemux   !
       mpegvideoparse ! mpeg2dec ! sdlvideosink
       Display the video portion of a .vob file (used on DVDs), outputting  to
       an SDL window

               gst-launch  filesrc  location=movie.mpg ! dvddemux name=demuxer
       demuxer. ! queue ! mpegvideoparse ! mpeg2dec ! sdlvideosink  demuxer. !
       queue ! mpegaudioparse ! mad ! audioconvert ! audioresample ! pulsesink
       Play both video and audio portions of an MPEG movie

               gst-launch  filesrc location=movie.mpg ! mpegdemux name=demuxer
       demuxer.  !  queue  !  mpegvideoparse  !  mpeg2dec  !  videoconvert   !
       sdlvideosink   demuxer. ! queue ! mpegaudioparse ! mad ! 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 textoverlay name=overlay ! videoconvert ! videoscale
       !  autovideosink   filesrc location=movie.avi ! decodebin  !  videocon-
       vert  !  overlay.video_sink    filesrc  location=movie.srt ! subparse !

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

               gst-launch    playbin    uri=file:///path/to/movie.avi     sub-

       Network streaming

       Stream video using RTP and network elements.

               gst-launch   v4l2src   !   video/x-raw,width=128,height=96,for-
       mat=UYVY ! videoconvert ! ffenc_h263 ! video/x-h263 ! rtph263ppay pt=96
       ! udpsink host= port=5000
       This command would be run on the transmitter

               gst-launch   udpsrc   port=5000   !  application/x-rtp,  clock-
       rate=90000,payload=96 !  rtph263pdepay  queue-delay=0  !  ffdec_h263  !
       Use this command on the receiver


               gst-launch -v fakesrc num-buffers=16 ! fakesink
       Generate a null stream and ignore it (and print out details).

               gst-launch  audiotestsrc ! audioconvert ! audioresample ! puls-
       Generate a pure sine tone to test the audio output

               gst-launch videotestsrc ! xvimagesink
               gst-launch videotestsrc ! ximagesink
       Generate a familiar test pattern to test the video output

       Automatic linking

       You can use the decodebin element to  automatically  select  the  right
       elements to get a working pipeline.

               gst-launch  filesrc  location=musicfile ! decodebin ! audiocon-
       vert ! audioresample ! pulsesink
       Play any supported audio format

               gst-launch filesrc location=videofile ! decodebin  name=decoder
       decoder.  ! queue ! audioconvert ! audioresample ! pulsesink   decoder.
       !  videoconvert ! xvimagesink
       Play any supported video format with video and  audio  output.  Threads
       are used automatically. To make this even easier, you can use the play-
       bin element:

               gst-launch playbin uri=file:///home/joe/foo.avi

       Filtered connections

       These examples show you how to use filtered caps.

               gst-launch  videotestsrc  !   'video/x-raw,format=YUY2;video/x-
       raw,format=YV12' ! xvimagesink
       Show a test image and use the YUY2 or YV12 video format for this.

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

              Comma-separated  list  of  debug  categories  and  levels  (e.g.
              GST_DEBUG=totem:4,typefind:5). '*' is allowed as a  wildcard  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) (e.g. GST_DEBUG=*audio*:LOG)

              When this environment variable is set, coloured debug output  is

              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

              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.  'i486',
              'i686', 'x86-64',

              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.

              Specifies  a list of directories to scan for additional plugins.
              These take precedence over the system plugins.

              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

              Set this variable to a file path to redirect all GStreamer debug
              messages  to  this  file.  If left unset, debug messages with be
              output unto the standard error.

              Useful Orc environment variable. Set  ORC_CODE=debug  to  enable
              debuggers  such as gdb to create useful backtraces from Orc-gen-
              erated 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).

              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.

               The  plugin  cache; can be deleted at any time, will be re-cre-
               ated automatically when  it  does  not  exist  yet  or  plugins
               change.  Based on XDG_CACHE_DIR, so may be in a different loca-
               tion than the one suggested.

       See attributes(7) for descriptions of the following attributes:

       |ATTRIBUTE TYPE |      ATTRIBUTE VALUE        |
       |Availability   | library/desktop/gstreamer-1 |
       |Stability      | Pass-through volatile       |
       gst-inspect-1.0(1), gst-launch-1.0(1),

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

       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source     was     downloaded     from      https://gstreamer.freedesk-

       Further information about this software can be found on the open source
       community website at https://gstreamer.freedesktop.org/.

                                   May 2007                       GStreamer(1)