Multiple fadeIn/fadeOut effects in one audio file with ffmpeg

Question

I have some problem to add several fade effects to one audio file. When I try to use a command like this:

ffmpeg -y -i /home/user/video/test/sound.mp3 -af \"afad         


        

Answer 1

take a look here: ffmpeg volume filters

volume='if(lt(t,10),1,max(1-(t-10)/5,0))':eval=frame

complete command:

ffmpeg -i movie.wav -filter volume='if(lt(t,10),1,max(1-(t-10)/5,0))':eval=frame modified-movie.wav

Answer 2

Works for me with ffmpeg 2.5.2.

I'm using fade in and fade out audio filter, both for the duration of 3 seconds.

ffmpeg -i audio.mp3 -af 'afade=t=in:ss=0:d=3,afade=t=out:st=27:d=3' out.mp3

I'd recommend to upgrade your ffmpeg, as this might be a bug. More information in the docs.

Answer 3

The problem is that after fading out the audio you are trying to fade in the silence.

The solution is to disable the fade out filter when you want to start fading in.

You can achieve that with Timeline Editing to enable the filters for a particular amount of time.

The following example works just fine:

ffmpeg -i input.mp3 -af "afade=enable='between(t,0,3)':t=in:ss=0:d=3,afade=enable='between(t,7,10)':t=out:st=7:d=3,afade=enable='between(t,10,13)':t=in:st=10:d=3,afade=enable='between(t,13,16)':t=out:st=13:d=3" -t 16 output.mp3