How can I split the 5.1 audio channels from an AC3 file into individuals streams (preferably on a Mac)?

7

2

I have a file that I've pulled from a DVD that is apparently in AC3 5.1 format. The extension is .AC3 and it opens an plays in QuickTime, VLC etc.

What I want is each individual channel in a separate file, but I can't seem to find any tools that will allow be to do that.

Is there a way to split the file I have, or alternatively is there a way to pull the audio streams from a 5.1 DVD?

Drarok

Posted 2010-06-17T02:00:39.153

Reputation: 210

What do you mean by split? If you mean extracting only some of the channels (say, front left and front right) from AC3, then it's not possible without re-encoding. (which means either file size increase or quality loss) – Display Name – 2016-03-13T08:37:23.797

Answers

6

Assuming you have it in an MP4 container... the following should output an MP4 with six different audio streams, each one a mono rip of one of the audio channels:

ffmpeg -i input.mp4 -vn -filter_complex channelsplit output.mp4

This more complicated ffmpeg command will split the AC3 file into several different files:

ffmpeg -i input.mp4 -vn -filter_complex 'channelsplit=channel_layout=5.1[FL][FR][FC][LFE][SL][SR]' -map '[FL]' front_left.ac3 -map '[FR]' front_right.ac3 -map '[FC]' front_center.ac3 -map '[LFE]' lfe.ac3 -map '[SL]' side_left.ac3 -map '[SR]' side_right.ac3

This will only work on builds of ffmpeg compiled with support for filters... but I think most ffmpeg builds should have this.

evilsoup

Posted 2010-06-17T02:00:39.153

Reputation: 10 085

3

Audacity has an Export Multiple feature that does exactly that.

reedstrm

Posted 2010-06-17T02:00:39.153

Reputation: 246