The VideoLAN Forums

Is it possible to save just the audio from a movie stream to a file using vlc?
Also, is it possible to use vlc to add an audio track to a movie file somehow?

The reason I ask is I have two files with the same movie. One of them has very good video quality but no english audio track, and the other has an engish audio track but poor video quality. I am trying to get the best of both worlds.

It is certainly possible to extract audio only. Go to Advanced File Open then at the bottom of the file dialogue select Stream from the drop-down menu to the left of the PLAY button. Select File as the stream output, OGG for the encapsulation, Vorbis for the codec then press STREAM.

This will give you an OGG/Vorbis file. I guess you could also select RAW as the encapsulation and MP3 as the codec to get MP3. If you don't bother selecting a video codec you shouldn't get any video output.

I don't think it is possible to add a new audio track though. Perhaps mencoder would be a better application for this. I think, IIRC, it can take separate audio and video sources.

Hope that helps at least part of the way.