Changing out soundtrack with ffmpeg. Example of moving ogg soundtrack to matroska (mkv)

Matroska file format (mkv) is specified with -f matroskaoption. It should be supported by ffmpeg (version 0.7.3) in Ubuntu 11.10.

Use ffmpeg -formats for a list of supported file formats.

To merge specific streams (audio or video) from several files use -i option for each input and -map input_index[:stream_index]. For example, the following command merges the first stream of the first input with the second input and keeps the codecs:

ffmpeg -i input.mkv -i input_audio.ogg -map 0:0 -map 1 -vcodec copy -acodec copy output.mkv

http://ffmpeg.gusari.org/viewtopic.php?f=25&t=611

ubuntu video conversion

http://ubuntuguide.org/wiki/Video_Conversion#FFMPEG