id3 technical details


The section we're interested in,

   This frame replaces the old 30-character comment field in ID3v1. It
   consists of a frame head followed by encoding, language and content
   descriptors and is ended with the actual comment as a text string.
   Newline characters are allowed in the comment text string. There may
   be more than one comment frame in each tag, but only one with the same
   language and content descriptor.

     Comment                   "COM"
     Frame size                $xx xx xx
     Text encoding             $xx
     Language                  $xx xx xx
     Short content description <textstring> $00 (00)
     The actual text           <textstring>