[FFmpeg-user] Audio ducking of input music based on vocals in another audio file

[Gyan Doshi]

On 14-08-2018 07:45 PM, Will Lewis wrote:
> Hi,
> 
> I'm looking for a way to take an music audio file and automate the ducking
> on its volume level based on vocals in a separate audio file. The output
> should just be the music audio with volume reduced in response to that
> input. I believe this is similar to side channel audio compression.
> 
> Is this something that is achievable with ffmpeg? or could be with a custom
> audio filter?
This _is_ sidechain compression and ffmpeg has the sidechaincompress 
filter See https://ffmpeg.org/ffmpeg-filters.html#sidechaincompress

Gyan