using FFMPEG with silencedetect to remove audio silence

Question

I am trying to use the following command with the latest ffmpeg build to remove silence from my .mp3 files:

ffmpeg -i SILENCE.mp3 -af silencedetect=n=-50dB:d         


        

Answer 1

ffmpeg silence detect only detects the silence. One has to scan the ffmpeg output and cut the mp3 file.

In theory, this would be done as:

ffmpeg -i INPUT.mp3 -af silencedetect=n=-50dB:d=1

and monitoring for output in form of:

[silencedetect @ 0000000004970f80] silence_start: -0.00154195
[silencedetect @ 0000000004970f80] silence_end: 3.20435 | silence_duration: 3.2059
...
[silencedetect @ 0000000004970f80] silence_start: 343.84

And, cutting start and end silence:

ffmpeg -i INPUT.mp3 -ss 3.20435 -t (343.84-3.20435)

I ended up writing a small Java program which does it. Hints:

• ffmpeg writes to stderr. This means, you need to use ProcessBuilder and redirectErrorStream(true).
• secondly, you need to extract the silence_start and silence_end information.
• then you might use the timestamps to cut the video

Following code may be helpful: Using Java and FFMPEG with silencedetect to remove audio silence