mplex - MPEG 1/2 program/system stream multiplexer


   mplex   [-f|--format   format_code]   [-i|--vdr-index]   index_pathname
   [-v|--verbose    num]     [-b|--video-buffer     video_buffer_size_kB[,
   video_buffer_size_kB...]]    [-L|--lpcm-params   params[,   params...]]
   [-r|--mux-bitrate muxed_bitrate_kbps] [-l|--mux-limit num]  [-O|--sync-
   offset   num[ms|s|mpt]]   [-d|--subpicture-delay  [ms|s|mpt|c][:stream-
   id][,delay[:stream-id]]   [-R|--run-in   num]   [-V|--vbr]   [-C|--cbr]
   [-s|--sector-size     sector_size_B]     [-p|--packets-per-pack    num]
   [-h|--system-headers] [-S|--max-segment-size  output_filesize_limit_MB]

   [-?|--help] -o|--output output_pathname_pattern input_file...


   Mplex  is  a general-purpose audio/video multiplexer for MPEG-1/MPEG-2.
   It accepts one or more MPEG-1/2 video stream, MPEG layer I/II/III, DTS,
   AC3  and  LPCM  audio  streams  and  multiplexes  them  into a combined
   program/system stream according to  the  constraints  specified.   Many
   different  types  of  output structure are supported along with presets
   for standard VCD and SVCD streams.  These latter can be  burned  to  CD
   using tools such as vcdimager(1) and played in stand-alone players.

   It  is  also  capable of automatically splitting the output stream into
   chunks  of  a  specified  size  either  independently  or  at  sequence
   end/start points in the input video stream.


   -o|--output output_filename_pattern
          This mandatory option sets the pattern for the name(s) of output

          An integer format code (e.g. %d) in the name is replaced by  the
          number of the file generated (see printf(3)).

   -v|--verbose num
          Set verbosity level to num:
           0 - warnings and errors only,
           1 - information as well,
           2 - really verbose.

          Display a synopsis of the command syntax.


   -f|--format format_code
          This  command allows one of a number of convenient preset output
          formats or generic MPEG1 or MPEG2 output to be selected. For the
          generic  formats  other  function letters can be used to control
          many  aspects  of  the  multiplexed  stream.   For  VCD/SVCD/DVD
          compliant  output  the corresponding formats must be used as the
          standards require  the  multiplexer  to  enforce  a  variety  of
          special constraints on the structure of the output stream.

           0  -  Generic  MPEG1.   A  simple  general-purpose MPEG1 format
          primarily suitable for software decoders.  Buffer sizes and  VBR
          must be specified.  Bit-rate can be auto-detected.
           1 - VCD.  Standard VCD.  Overrides other option settings.
           2 - User VCD.  VCD format but buffer size, bit rate and VBR can
          be set manually.
           3 - Generic MPEG2.  Like 0 except MPEG2.
           4 - SVCD.  Standard SVCD.  Overrides other option settings.
           5 - User-rate SVCD.  SVCD format but buffer size bit  rate  and
          VBR can be set.
           6  - VCD Stills stream (mixed mode with hi-res and standard-res
          image streams       multiplexed are supported).
           7 - SVCD Stills stream.
           8 - DVD (with NAV sectors). Don't get  too  excited.   This  is
          really a
           very  minimal  mux  format.   It includes empty versions of the
           VOBU start sectors  DVD  VOB's  include.   This  is  enough  to
          persuade some
           hardware players to play the stream but is a long way from full
          DVD authoring.
           9 - DVD.  As above but without the empty VOBU sectors.

   -W|--workarounds workaround_flag [,workaround_flag...]
          A comma-seperated list of flags that  set  special  work-arounds
          for what are suspected to be parser Bugs in widely used players.
          No workarounds are (currently) implemented but history  suggests
          this  may  change quickly ;-) -i|--vdr-index index_pathname This
          tells mplex to generate an index file  for  the  output  in  the
          format  used  by the 'vdr' (video disk recorder package). Useful
          if you want to write output into vdr's recordings directory  for
          playback on your video recorder PC. This probably only useful in
          combination with -f 9.

   -r|--mux-bitrate num
          The total (non VBR) / peak (VBR) bit-rate of the  output  stream
          in  k  Bits/sec.  If  unspecified  and not set by a preset it is
          automatically calculated from the input stream.

   -b|--video-buffer numlist
          A comma-seperateed list of video decoder buffer sizes in KB  for
          the  video  streams (given in the order the video streams appear
          on the command line).  The  default  is  46KB  the  (tiny)  size
          specified  for  VCD.   The  size  to  use  for SVCD is the (more
          reasonable) 230KB.   If  you  are  encoding  for  a  half-decent
          software decoder it makes sense to push this up to 500K or more.

          [, samples_per_sec:channels:bits_per_sample
          A  comma-seperated  list  of  paramter  sets  for the lpcm audio
          streams (given in the order  the  lpcm  streams  appear  on  the
          command  line).   Each parameter set comprises the sampling rate
          in Hz, the number of channels, and the number of bits per sample
          seperated by colons.  For example, the default 48kHz two-channel
          16-bit audio would be specified as 48000:2:16.

          Note: these parameters are necessary because mplex  expects  raw
          LPCM  audio  data without any headers.  That is: for each sample
          point a group of 16,20, or 24 bit amplitude values, one for each
          channel.  Amplitude values are signed with the constituent bytes
          in big-endian (most significant bytes first) order.  For 20  bit
          samples  I  am  not  sure but what documentation I have suggests
          such samples are padded at the lsb end so that  they  byte-align
          at the most significant bits.

   -l|--mux-limit num
          Multiplex   limit.   Multiplex  only  the  specified  number  of
          seconds.  Useful for tuning and debugging.

   -O|--sync-offset num[ms|s|mpt|c]
          Set the presentation timestamp offset  of  video  stream  w.r.t.
          audio  stream  (video-audio)  in  mSec.    This  flag is used to
          produce a stream with synchronised audio/video when  one  stream
          started before/after the other.  This is common when transcoding
          as the synchronisation information is typically lost during  the
          (seperate) decoding/encoding of audio and video.

          By appending 's', 'ms' or 'mpt' the offset can given in seconds,
          milliseconds  or  MPEG  clock  ticks  (1/90000th  of  a  second)
          respectively.  If no suffix is given milliseconds are assumed.

   -d|--subpicture-delay num[ms|s|mpt|c][:stream-id][,delay[:stream-id]]
          Specify offset of timestamps (video-subpicture) in msec sec, mpt
          or clock-ticks. If no suffix is given milliseconds are assumed.

          The intention of the adding subtitle support was to enable mplex
          to  mux all streams necessary for a DVD so that the mpeg2 stream
          created can be used directly for further dvd creation. Currently
          only ps1 streams (like created by tcextract) are supported

          Valid  subtitle stream are in a range of 32-63 (including).  You
          may want to specify each stream you mplex, use  ","  to  delimit
          each stream.

          Example:  If  you  want  to  mux  one  video,  one audio and two
          subtitle streams having delays of 500 and  1000  ms,  the  first
          shall have id 32, the second is 33 (Subtitle streams 0 and 1):

          $  mplex  -f  8  -o  my_mpeg.mpeg -d 500:32,1000:33 video_in.mpv
          audio_in.m2a subtitle_0.ps1 subtitle_1.ps1

   -R|--run-in num
          Set a non-default  run-in  (the  time  data  is  preloaded  into
          buffers  before  decoding  is  scheduled)  at  the start of each
          sequence in video frame intervals.  By default a run-in matching
          the specified size of the video and audio buffers in the decoder
          and the type of multiplexing (constant or variable bit-rate)  is
          selected automatically.

          Force  variable  bit  rate multiplexing even if selected profile
          defaults to constant-bit-rate.

          Force constant bit rate multiplexing even  if  selected  profile
          defaults to variable bit-rate.

   -s|--sector-size num
          This  option  specifies  the sector size of the output stream in

   -p|--packets-per-pack num
          This option specifies the number of  packets  per  pack  in  the
          output stream.

   -S|--max-segment-size num
          This option specifies the maximum size of output files in MBytes
          (2^10) When the limit is reached a  new file  is  started.   The
          default is (0) unlimited.

          Note:  This  option  is  not  for  splitting a long video across
          multiple VCD's or SVCD's.

          It simply splits a single long  sequence  into  in  a  way  that
          prevents  bits  of a video GOP(group of pictures) or audio frame
          being split between chunks.  This is fine for formats like  that
          used  for  DVDs  where  all  stream parameters appear every GOP.
          However, for VCD / SVCD it won't work as the players expect each
          file to start a new MPEG sequence.

          For  VCD  /  SVCD  a  different  technique  is  used.   If mplex
          encounters a sequence break (sequence end followed by start)  in
          the input video stream it starts a new output stream and file at
          the  sequence  start.   Thus  to  split  a  long  video   across
          VCD's/SVCD's you have to get the MPEG video encoder to introduce
          sequence splits at the right points (see mpeg2enc(1) for details
          of how to do this).

          This  flag  makes  mplex ignore sequence end markers embedded in
          the first video stream instead of  switching  to  a  new  output
          file.  This is sometimes useful splitting a long stream in files
          based on a -S limit that  doesn't  need  a  run-in/run-out  like

          A  system  header is generated in every pack rather than just in
          the first.


   When multiplexing using mplex you may get  warning  or  error  messages
   complaining  about  buffer underflow.  This means that the bit-rate you
   have specified is simply too low to permit the video and  audio  to  be
   played  back  without  skipping.  The fix is to either reduce the data-
   rate of the input material or increased the output stream bit-rate.


   The multiplexer should handle MPEG(5.1) audio.


   This man page was written by Andrew Stevens.
   If you have questions, remarks, problems or you just  want  to  contact
   the developers, the main mailing list for the MJPEG-tools is:

   For more info, see our website at


   mpeg2enc(1),  mp2enc(1), lavrec(1), lavplay(1), lav2yuv(1), lav2wav(1),


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