Only the music...

[Xodarap]

Is it possible to pull only the music (i.e. no sound effects or voices) from a movie? At first I assumed that there must be a separate channel so they can change languages over the top, but then I realized that the inefficient reality of totally separate audio tracks is fairly likely.

If there's no *real* way to do it, I'm aware that I could probably pull out the center channel and maybe the two back ones to reduce voices.

[setarip_old]

Using an audio editor, such as GoldWave or similar, try turning off the midrange...

[Xodarap]

I know I can use a parametric EQ, too. I was just wondering if --- as I know so little of AC3 encoding --- there was a retrievable "track list" sort of thing. To *actually* get just the music. Some DVDs, for example (My .Hack//Sign collection has this), have a "just the music" option, so you watch them with no voices or sounds. I was wondering if they were "turning off" the voices, or actually programming in an entire separate track.

[setarip_old]

I believe you'll find that, in such instances, there is simply a separate music-only track...

[Arite]

It may be possible to reduce the sound effects from the soundtrack of a movie - you would probably have to study the layout and placement of each of the audio track (e.g. speech - mainly front speakers, ambience effects - rear speakers etc.).

For example, a simple method of reducing (although quality loss is fairly high) the "front" channel (such as a singer/drums) from a piece of stereo audio is to invert one of the channels and merge the two together to make one mono track. This works by cancelling out the similar sounds (the sounds from both speakers - i.e. the "front" channel) from the two channels, leaving just the channel-specific audio. Depending on where the music, speech and sound effects come from you may be able to isolate just the music. Perhaps something like that along with parametric equalisation would provide acceptable results.

That, however, is what I imagine you were suggesting in your first post? I do not know any *real* method of doing it - as far as I know, AC3 audio does not contain any extra meta information - it is just a multi (or single) channel lossy audio compressor.

Cheers, Arite.

[Xodarap]

I believe you'll find that, in such instances, there is simply a separate music-only track...


Hrm. Does that seem very mid-90s to anyone else? :P How much more efficient it would be to have swappable tracks...

[foxyshadis]

Sure, and that's when DVD was designed. :p It probably wasn't done originally because it would mean 2x the decoding power needed, and no home theater systems would have supported it. I think one or both of the HD specs include layered-audio as an option, but I can't find information on it at the moment. You could fit a lot more languages in the same space, but I doubt more than a few sound engineers would ever bother to use it anyway.