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rubyaudiomp3checksum

Reading MP3 audio data, or calculating the checksum thereof

Is there a Ruby library that will allow me to either calculate the checksum of an MP3 file's audio data (minus the metadata) or allow me to read in an MP3's audio data to calculate the checksum myself?

I'm looking for something like this:

mp3 = Mp3Lib::MP3.new('/path/to/song.mp3')
mp3.audio.sha1sum # => the sha1 checksum of _only_ the audio, minus the metadata

I found Mp3Info, but it seems a bit tedious. When initializing an Mp3Info object, you can get the frames where the actual audio data begins and ends.

Solution

  • Isn't the ID3 tag stored either at the end of the file (ID3 v1) in a 128-byte block, or in a block at the start of the file (ID3v2.3 and v2.4) ? (id3.org)

    You could use the audio_content method from Mp3Info, and read that much data from the file, though it's probably not much more complicated to have a look in the file yourself and work out where the headers aren't.