Section: User Commands (1)
Updated: November 2004
ogmcat - Concatenate several OGG/OGM files into one big OGG/OGM file
] -o outname inname1
ogmcat does NOT work at the moment. It is work in progress. I included it
just out of laziness (otherwise I'd have to remove it from the
Makefile/configure stuff prior to releasing this version).
ogmcat can be used to concatenate several OGG/OGM files into one big
file if they are of the same type. For a more in-depth description refer
to the LIMITATIONS section.
- -o, --output outname
Output to 'outname'.
Use 'inname1', 'inname2' etc as the sources.
- -m, --manualsync n
Specifies a manual sync value in ms that will be added to each stream's
presentation timestamps along with the value calculated by the chosen
sync algorithm (see the -s option). This option can be used for each
input file although it has no effect if used for the first one as well.
- -s, --sync nr
Uses sync mode nr. Valid values are 0 - 4. The default value is shown
on ogmcat's help screen.
- -n, --nosafetychecks
Disable the safety checks made prior to the concatenating. The resulting file
may be unplayable. See the LIMITATIONS section for further details.
- -v, --verbose
Be verbose and show each OGG packet.
Can be used twice to increase verbosity.
- -h, --help
Show this help.
- -V, --version
Show version information.
Concatenating streams is difficult at the best and might even be impossible.
makes very strict comparisons between the streams
contained in the input files. The checks done include:
general: All streams with the same serial number must be of the same type
(video, audio, Vorbis audio or text streams).
general: If a stream exists in one file it must in the other files
video streams: The codec FourCC, width, height and FPS must match.
Vorbis streams: The sample rate and the number of channels must match.
other audio streams: The codec ID, sample rate, bits per sample and number
of channels must match.
text/subtitle streams: The 'time unit' must match.
The user can forcefully override the last four checks with the -n
parameter. The checks marked as 'general' cannot be overridden this way.
Audio/video synchronization might not be ok in the resulting file even if
the source files were perfectly in sync. The user can experiment with the
-s parameter which causes ogmcat to use slightly different
algorithms for calculating the granulepos values for the audio and text
streams. The range of valid parameters will be printed on ogmcat's
If none of the synchronization algorithms provided works correctly then
the user can also manually add a synchronization offset using the -m
option for each input file.
was written by Moritz Bunkus <email@example.com
The newest version can always be found at