Extracting MP3 audio from an AVI file with ffmpeg
I look this up every few months, so here it is in one place. ffmpeg takes the video apart and writes just the audio track to an MP3 file. The whole file: ffmpeg -i sample.avi -vn -c:a libmp3lame -b:a 256k sample.mp3 -vn drops the video stream, -c:a libmp3lame selects the MP3 encoder and -b:a 256k sets the audio bitrate. For a variable bitrate instead, replace -b:a 256k with -q:a 2, which gives roughly 190 kbit/s at a noticeably better size-to-quality ratio.
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