Actually, you want to unpack them as four bytes. unpack "CCCC". ID3 has this wacky format that stores a 28-bit integer with 7 bits per byte, which I see the OP is already aware of.

The pack "I" format is not nearly as useful as you might think, because the length and byte order are both platform-dependent. You usually want to stick with "N" or "V".

In reply to Re^2: ID3v2 TAG unpack uninitialized value by no_slogan
in thread ID3v2 TAG unpack uninitialized value by thanos1983

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