Section: User Commands (1)
Updated: 09th January 2003
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tcdemux - demultiplex a program stream
tcdemux is Copyright (C) by Thomas Ístreich.
is part of and usually called by transcode.
However, it can also be used independently.
tcdemux reads source (from stdin if not explicitely defined) and
prints on the standard output.
- -i name
Specify input source. If ommited, stdin is assumed.
- -x codec
Process only packets containing given
Examples are "mpeg2" for MPEG video or "ac3" for audio packets.
- -t magic
Specify the input file type
Useful for using
in pipelines. This is normally autodetected.
- -a ach[,vch]
Process only packets containing given audio track
and video track
Most program stream feature multiple audio tracks but only a single video stream. Default is "-a 0,0".
- -s 0xnn
Select specific multimedia track using the standard identifier
This useful to extract subtitle packets.
- -f fps
Specify the frame rate
for subtitle meta information used by external applications.
- -S unit[,s1-s2]
Select a program unit
and a selected GOP range
for processing. A
is usually a set of GOPs that need to be synchronized
at the very beginning. This option can be used to eleminate junk units at the beginning of the main presentation or to select certain episodes of a TV series from a DVD. A GOP is a logical unit to be properly decoded, i.e., decoding can only start at the beginning of a GOP.
Do not skip initial sequence. Used internally by transcode.
- -A n[,m[,...]]
Select packets using an identifier for extracting only selected streams without processing. This is useful for size reduction of your multimedia stream. Example:
tcdemux -i big_dvd.vob -A 0xe0,0x81,0x20 > small_dvd.vob
extracts all packets for the video stream, AC3 audio track (1) and the
first subtitle stream (0).
- -M mode
Select synchronization strategy
This is how transcode selects the beginning of a video and audio stream to
assure both streams are sychronized for further processing:
0 no synchronization. Packets are printed directly to stdout.
1 synchronization based on PTS information found in the packet header. Audio packets are delayed until a suitable starting point is found. Default for PAL videos.
2 NTSC adapted synchronization mode. Detailed information for each GOP contained in the video stream are piped to a stdout to be processed by
the certain import modules. This enables adjusting the frame rate or inverse telecine, if necessary.
3 more advanced synchronization mode 1 with msec granular adjustment. Details delegated to transcode.
4 more advanced synchronization mode 2 with msec granular adjustment for NTSC materail. Details delegated to transcode.
5-7 undocumented debugging modes for internal use.
- -P file
Write GOP meta information to
instead of tdout.
Print a navigation log file for a given video stream to stdout. This is used for transcode's "psu mode" and "cluster mode".
- -d level
With this option you can specify a bitmask to enable different levels
of verbosity (if supported). You can combine several levels by adding the
Print version information and exit.
tcdemux is a front end for de-multiplexing program streams and is used in transcode┤s import modules.
tcprobe -i movie.vob -x mpeg2
extracts only MPEG video packets. Further processing, i.e., extracting the
elementary video stream is done by
was written by Thomas Ístreich
<email@example.com> with contributions from
many others. See AUTHORS for details.
- SEE ALSO
linux.jgfs.net manual pages