[plug] Linux and DVD Audio/AC3

[Matt Kemner]

On Wed, 17 Aug 2005, quoth Trevor Phillips:

> Has anyone had much experience with multi-channel audio under linux?
> I've recently obtained a DVD Video/Audio album, which sounds awesome
> on my home theatre system. I'd really like to be able to extract the
> DD 5.1 audio to a separate file, for playback on PCs.

You can extract audio with mplayer
I've used this before:
mplayer -v dvd://1 -vc dummy -vo null -ao pcm -aofile /tmp/track1.wav

but that copies 2 channel audio

You can force 5.1 with "-channels 6" but I don't know if the resulting
file (6 channel PCM) is a valid format that can be played by anything but
mplayer.

The -v flag on mplayer gives more information on the file/dvd it is
playing, including:

  DVD successfully opened.
  [open] audio stream: 0 audio format: ac3 (stereo) language: en aid: 128
  [open] audio stream: 1 audio format: ac3 (stereo) language: en aid: 129
  [open] number of audio channels on disk: 2.

Which you can use to choose the right audio stream, via the -aid flag.
(Otherwise you might end up with DVD commentary etc)

 - Matt