[FFmpeg-user] Downmix discrete 5.1 to stereo

[Moritz Barsnick]

Hi Carles,

On Wed, Jan 20, 2016 at 20:04:14 +0100, Carles Vila wrote:

> Hi, I'm struggling to find the correct command-line for converting 5.1 to
> stereo.
> My source are 6 x aiff (numbered _1 to _6, corresponding to L, R, C, LFE,
> Ls and Rs channels.
> 
> My idea is to obtain stereo the way the -ac 2 option does.

Six separate files means six separate streams. You should first map the
six streams into one stream containing six channels, and then let
ffmpeg downmix it for you.

Here's an example for the first part:
https://trac.ffmpeg.org/wiki/AudioChannelManipulation#a6mono5.1
You only need to add "-ac 2" as an output option in order to achieve a
downmix.

(Yes, there may be other ways to do this, but this seems the most
straightforward to me.)

Cheers,
Moritz