[FFmpeg-user] Combining long audio delayed files.

[Moritz Barsnick]

Hi Big,

On Wed, Mar 25, 2015 at 21:06:45 +0000, Big Funk wrote:
> I’m new here. I hope my question is relevant.

Sure.

> I’d like to combine two audio files, one significantly delayed with
> respect to the other.
[...]
> Is it possible to merge to two audio recordings into a stereo output
> file where audio from the two sources synched but individually
> controlled with respect to volume, bass, treble and so on ?

Using the amerge filter, you can combine several streams, e.g. your two
input files, into several channels of one stream (e.g. stereo).

Before that, you would need to put a defined amount of silence in front
of the delayed stream. An example is given here (for six-channel input,
whereas you would probably have just one):

http://superuser.com/a/579110

With regard to "with respect to volume, bass, treble and so on", you
can apply your respective filters to each separate stream first before
merging the streams with amerge at the end of the filter chain. (You
need to use -filter_complex like in the linked example.)

HTH,
Moritz