Rockbox mail archiveSubject: Re: ID3 tag problem with some MP3s
Re: ID3 tag problem with some MP3s
From: Johan Vromans <jvromans_at_squirrel.nl>
Date: Fri, 17 Oct 2003 13:10:20 +0200
Linus Nielsen Feltzing <linus_at_haxx.se> writes:
> As far as I can see, the APIC frame is declared to be 0x3454 bytes
> long, that is 13396 bytes. However, the APIC frame is in fact 0x56
> bytes longer than that, so Rockbox is not able to skip the APIC frame
> to find the next one.
> I adjusted the APIC length to its correct value and Rockbox had no
> problems reading all frames. Conclusion: the ID3 tag is corrupt.
I'm afraid you forgot to take unsynching into account.
You need to replace b11111111 b00000000 b111xxxxx by b11111111 b111xxxxx,
and \xff0000 -> \xff00. That will reduce the actual length to what is
specified in the header.
Forgetting to unsynch usually does not cause problems, unless there's
real binary information (e.g., and JPEG image) in the header.
Received on 2003-10-17