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audioffmpegavconv

insert audio into another audio file (eg a censor bleep)

I need to insert a short beep into another audio file (similar to a censorship bleep) using linux and/or php.

I'm thinking there should be some way to do it with ffmpeg (with some combination of -t, concat, map, async, adelay, itsoffset?) or avconv or mkvmerge - but haven't found anyone doing this. Maybe I need to do it in 2 stages somehow?

For example if I have a 60 second mp3 and want to beep out 2 seconds at 2 places the desired result would be:

0:00-0:15  from original
0:15-0:17  beep (overwrites the 2 secs of original)
0:17-0:40  from original
0:40-0:42  beep
0:42-0:60  from original

I have a 2 second beep.mp3, but can use something else instead like -i "sine=frequency=1000:duration=2"

Solution

  • You can use the concat demuxer.

    Create a text file, e.g.

    file main.wav
inpoint 0
outpoint 15
file beep.wav
file main.wav
inpoint 17
outpoint 40
file beep.wav
file main.wav
inpoint 40
outpoint 42

    and then

    ffmpeg -f concat -i list.txt out.mp3

    Convert the beep file to have the same sampling rate and channel count as the main audio.