4.26. Group identification registration
This frame enables grouping of otherwise unrelated frames. This can
be used when some frames are to be signed. To identify which frames
belongs to a set of frames a group identifier must be registered in
the tag with this frame. The 'Owner identifier' is a null-terminated
string with a URL [URL] containing an email address, or a link to a
location where an email address can be found, that belongs to the
organisation responsible for this grouping. Questions regarding the
grouping should be sent to the indicated email address. The 'Group
symbol' contains a value that associates the frame with this group
throughout the whole tag, in the range $80-F0. All other values are
reserved. The 'Group symbol' may optionally be followed by some group
specific data, e.g. a digital signature. There may be several "GRID"
frames in a tag but only one containing the same symbol and only one
containing the same owner identifier. The group symbol must be used
somewhere in the tag. See the description of the frame grouping flag
in the ID3v2 structure document [ID3v2-strct] for more information.
<Header for 'Group ID registration', ID: "GRID">
Owner identifier <text string> $00
Group symbol $xx
Group dependent data <binary data>
@author Eric Farng
@version $Revision: 1.4 $