Provided by: gstreamer1.0-tools_1.22.5-1_amd64 bug

NAME

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

SYNOPSIS

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

DESCRIPTION

       gst-launch-1.0 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. A  "preset"
       can also be set using the @preset=<preset name> syntax.

       For  a  complete  description  of  possible PIPELINE-DESCRIPTIONS see the section pipeline
       description below or consult the GStreamer documentation.

       Please note that gst-launch-1.0 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.

OPTIONS

       gst-launch-1.0 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.

       --no-position
               Do  not  print  current  position of 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 "force-position" option.

       --force-position
               Allow  printing  current  position  of 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 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. This is equivalent to
               setting the environment variable G_DEBUG  to  'fatal_warnings'  (see  the  section
               environment variables below for further information).

       --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 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" 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
               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.

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

       --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

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-1.0(1) to find out about
       properties and allowed values of different elements.
       Enumeration properties can be set by name, nick or value.

       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 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.

       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, that links the element to the left of
       it to the element 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.

       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 ...] }

PIPELINE EXAMPLES

       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

       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 !
       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 ! 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
       ! 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

       Display only the video portion of an MPEG-1 video file, outputting to an X display window
               gst-launch-1.0   filesrc   location=JB_FF9_TheGravityOfLove.mpg   !   dvddemux   !
       mpegvideoparse ! mpeg2dec ! 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
       ! 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 ! sdlvideosink  demuxer.  !  queue  !  mpegaudioparse  !
       mpg123audiodec ! audioconvert ! audioresample ! pulsesink

       Play an AVI movie with an external text subtitle stream
               gst-launch-1.0  filesrc  location=movie.mpg  !  mpegdemux  name=demuxer demuxer. !
       queue ! mpegvideoparse ! mpeg2dec ! videoconvert  !  sdlvideosink    demuxer.  !  queue  !
       mpegaudioparse ! mpg123audiodec ! audioconvert ! audioresample ! pulsesink

       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 ! decodebin ! videoconvert ! overlay.video_sink
       filesrc location=movie.srt ! subparse ! overlay.text_sink

       Play an AVI movie with an external text subtitle stream using playbin
               gst-launch-1.0                playbin                uri=file:///path/to/movie.avi
       suburi=file:///path/to/movie.srt

       Network streaming

       Stream video using RTP and network elements.

       This command would be run on the transmitter
               gst-launch-1.0    v4l2src    !    video/x-raw,width=128,height=96,format=UYVY    !
       videoconvert ! ffenc_h263 ! video/x-h263 ! rtph263ppay pt=96  !  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 !
       rtph263pdepay queue-delay=0 ! ffdec_h263 ! xvimagesink

       Diagnostic

       Generate a null stream and ignore it (and print out details).
               gst-launch-1.0 -v fakesrc num-buffers=16 ! fakesink

       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.

       Play any supported audio format
               gst-launch-1.0   filesrc   location=musicfile   !   decodebin   !  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  !  decodebin  name=decoder decoder. !
       queue ! audioconvert ! audioresample ! pulsesink   decoder. !  videoconvert ! xvimagesink
               gst-launch-1.0 playbin uri=file:///home/joe/foo.avi

       Filtered connections

       These examples show you how to use filtered caps.

       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

       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

       GST_DEBUG
              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)

       GST_DEBUG_NO_COLOR
              When this environment variable is set, coloured debug output is disabled.

       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.

       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. 'i486', 'i686', 'x86-64', 'ppc', etc. (check the  output  of
              "uname -i" and "uname -m" for details).

       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.

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

       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

       GST_DEBUG_FILE
              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.

       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).

       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.

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.

SEE ALSO

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

AUTHOR

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

                                             May 2007                                GStreamer(1)