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Topic: Monkey's Audio MD5 in foobar2000 is...wrong? (Read 6239 times) previous topic - next topic

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Monkey's Audio MD5 in foobar2000 is...wrong?
When I transcoded a FLAC file into a Monkey's Audio file, MD5 and Bit Comparison tests in foobar2000 showed the files were identical. Yet when I looked at the MD5s that were stored in each file's metadata, they were totally different. The same thing happened when I transcoded a WavPack file into a Monkey's Audio file. Is this due to a quirk in the APE format and the way it gets an MD5 signature? Or is foobar2000 not reading the MD5 signature correctly?

  • tuffy
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Monkey's Audio MD5 in foobar2000 is...wrong?
Reply #1
FLAC's MD5 sum is of the file's raw data when decompressed.  Monkey's Audio's MD5 sum is of different parts of the compressed .ape file.  So it's okay that the two don't match up.

  • db1989
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  • Global Moderator
Monkey's Audio MD5 in foobar2000 is...wrong?
Reply #2
Monkey's Audio's MD5 sum is of different parts of the compressed .ape file.
Which parts? I trust you you don’t mean everything; computing such an MD5 would require analysing the whole file including its not-yet-existent MD5…

  • tuffy
  • [*][*][*]
Monkey's Audio MD5 in foobar2000 is...wrong?
Reply #3
Monkey's Audio's MD5 sum is of different parts of the compressed .ape file.
Which parts? I trust you you don’t mean everything; computing such an MD5 would require analysing the whole file including its not-yet-existent MD5…

It's the MD5 sum of everything from the end of the seektable to the end of the file data (not counting any metadata tags), and everything from the end of the descriptor to the end of the seektable.  Since the MD5 sum lives in the descriptor at the start of the file, it all works out.

  • greynol
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  • Global Moderator
Monkey's Audio MD5 in foobar2000 is...wrong?
Reply #4
13 February 2016: The world was blessed with the passing of a truly vile and wretched person.

Your eyes cannot hear.