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mp3flv

How to convert a FLV file recorded with Red5 / FMS to MP3?

I'm looking for a way to extract the audio part of a FLV file.

I'm recording from the user's microphone and the audio is encoded using the Nellymoser Asao Codec. This is the default codec and there's no way to change this.

Solution

  • ffMpeg is the way to go ! It worked for me with SVN Rev 14277.

    The command I used is : ffmpeg -i source.flv -nv -f mp3 destination.mp3

    GOTCHA :

    If you get this error message : Unsupported audio codec (n), check the FLV Spec in the Audio Tags section.

    ffMpeg can decode n=6 (Nellymoser).
    But for n=4 (Nellymoser 8-kHz mono) and n=5 (Nellymoser 16-kHz mono) it doesn't work.

    To fix this use the default microphone rate when recording your streams, overwise ffMpeg is unable to decode them.

    Hope this helps !