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       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

       Please   note  that  gst-launch  is  primarily  a  debugging  tool  for
       developers 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.

       -o FILE, --output=FILE
               Save  XML  representation  of  pipeline  to   FILE   and   exit
               (DEPRECATED, DO NOT USE)

       -f, --no-fault
               Do not install a fault handler

               Do  not  install signal handlers for SIGUSR1 (play) and SIGUSR2

       -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  0-5
               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,oggdemux:5

               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.

               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

               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
       properties  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,...]]
       [[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.


       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.


       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
       - 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
       - 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 ...] )


       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 explicitely.


       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", "osxaudiosink", or "artsdsink".
       Likewise,  "xvimagesink"  can   be   substituted   with   "ximagesink",
       "sdlvideosink",  "osxvideosink",  or "aasink". 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  ffmpegcolorspace  (for  video) in front of the sink to make
       things work.

       Audio playback

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

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

               gst-launch gnomevfssrc location=music.mp3 ! mad ! osssink
               gst-launch  gnomevfssrc  location= !
       mad ! audioconvert ! audioresample ! osssink
       Play an mp3 file or an http stream using GNOME-VFS

               gst-launch gnomevfssrc location=smb://computer/music.mp3 !  mad
       ! audioconvert ! audioresample ! osssink
       Use GNOME-VFS to play an mp3 file located on an SMB server

       Format conversion

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

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


               gst-launch filesrc location=music.wav ! wavparse ! audioconvert
       ! audioresample ! osssink
       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
       ! 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  !
       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-0.10
       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  osssrc  !  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   !
       dvddemux ! 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 ! mpeg2dec !
       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  ! mpeg2dec ! sdlvideosink  demuxer. ! queue ! mad !
       audioconvert ! audioresample ! osssink
       Play both video and audio portions of an MPEG movie

               gst-launch filesrc location=movie.mpg ! mpegdemux  name=demuxer
       demuxer.   !   queue  !  mpeg2dec  !  ffmpegcolorspace  !  sdlvideosink
       demuxer. ! queue ! mad ! audioconvert ! audioresample ! osssink
       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  !  ffmpegcolorspace  !
       videoscale ! autovideosink   filesrc location=movie.avi ! decodebin2  !
       ffmpegcolorspace  !  overlay.video_sink    filesrc !
       subparse ! overlay.text_sink

       Play an AVI movie with an external text subtitle stream using playbin2

               gst-launch        playbin2        uri=file:///path/to/movie.avi

       Network streaming

       Stream video using RTP and network elements.

               gst-launch           v4l2src           !           video/x-raw-
       yuv,width=128,height=96,format='(fourcc)'UYVY  !   ffmpegcolorspace   !
       ffenc_h263    !    video/x-h263   !   rtph263ppay   pt=96   !   udpsink
       host= port=5000 sync=false
       Use this command on the receiver

               gst-launch  udpsrc  port=5000   !   application/x-rtp,   clock-
       rate=90000,payload=96  !  rtph263pdepay  queue-delay=0  !  ffdec_h263 !
       This command would be run on the transmitter


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

               gst-launch  audiotestsrc  !  audioconvert  !  audioresample   !
       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    !
       audioconvert ! audioresample ! osssink
       Play any supported audio format

               gst-launch  filesrc location=videofile ! decodebin name=decoder
       decoder. ! queue ! audioconvert ! audioresample ! osssink   decoder.  !
       ffmpegcolorspace ! xvimagesink
       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 playbin uri=file:///home/joe/foo.avi

       Filtered connections

       These examples show you how to use filtered caps.

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

               gst-launch           osssrc           !           'audio/x-raw-
       ! 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.

              When  this environment variable is set, coloured debug output is

              When set to a filesystem  path,  store  dot  files  of  pipeline
              graphs there.

              Path    of    the    plugin    registry    file.    Default   is
              ~/.gstreamer-0.10/registry-CPU.xml where CPU is the  machine/cpu
              type  GStreamer was compiled for, e.g. 'i486', 'i686', 'x86-64',
              'ppc', etc. (check the output of "uname -i" and "uname  -m"  for

              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

              Useful  liboil  environment  variable.  Set OIL_CPU_FLAGS=0 when
              valgrind  or  other  debugging  tools  trip  over  liboil's  CPU
              detection   (quite   a  few  important  GStreamer  plugins  like
              videotestsrc, audioconvert or audioresample use liboil).

              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 xml plugin database; can be deleted at any  time,  will  be
               re-created  automatically when it does not exist yet or plugins


       gst-feedback(1), gst-inspect(1), gst-typefind(1)


       The GStreamer team at

                                   May 2007                       GStreamer(1)