Increase volume of one channel in 8channel .wav file ffmpeg

Question

I have 8-channel .wav file with sine wave in there. I would like to increase the volume of only 4th channel in this file. I don't know how to do it though.

ffmpeg -i input.wav -af "volume=1.5" output.wav

This will increase volume for all 8 channels. How can i apply it only to 1 channel (4th one) but still maintain the 8-channel .wav file?

Answer 1

这样的事情应该起作用： ffmpeg -i input.wav -af "pan=8c|c0=c0|c1=c1|c2=c2|c3=1.5*c3|c4=c4|c5=c5|c6=c6|c7=c7" output.wav