[FFmpeg-user] amid fails when there are more than 8 input channels (in one file)

[Moritz Barsnick]

On Wed, May 02, 2018 at 15:51:09 +0200, Bouke / VideoToolShed wrote:
> Strange thing, more than 8 channels give silent output:
> ffmpeg -i 9Ch_orMore.WAV -filter_complex "[0:0][0:0] amix=inputs=2,pan=mono|c0=c0+c1” -ac 1 mono.wav
> gives on errors whatsoever, but output is silent.

"No" errors?

This works for me (9 inputs):
$ ffmpeg -f lavfi -i anoisesrc=seed=0 -f lavfi -i anoisesrc=seed=1 -f lavfi -i anoisesrc=seed=2 -f lavfi -i anoisesrc=seed=3 -f lavfi -i anoisesrc=seed=4 -f lavfi -i anoisesrc=seed=5 -f lavfi -i anoisesrc=seed=6 -f lavfi -i anoisesrc=seed=7 -f lavfi -i anoisesrc=seed=8 -filter_complex 'amerge=inputs=9,pan=mono|c0=c0+c1,volumedetect' -t 5 -f null -

(volumedetect is there to verify that it is not silent.)

What are you trying to achieve with amix?

Moritz