NAME

MP3::Tag::ID3v2-Data - GetFrame() Data Format

DESCRIPTION

This document describes how to use the results of the GetFrame function of MP3::Tag::ID3v2, thus the data format of frames retrieved with MP3::Tag::ID3v2::GetFrame().

Calling GetFrame()

You have to call GetFrame() like this:

(\$info, \$long) = GetFrame(\$id); # or

(\$info, \$long) = GetFrame(\$id, 'raw');

\$id has to be a name of a frame like "APIC". The names of all frames found in a tag can be retrieved with the GetFrameIDs() function.

Using the returned data

In the ID3v2.3 specifications $#frames frames are defined, which can contain very different information. That means also that GetFrame returns the information found in a frame in different ways.

Simple Frames

A lot of the tags contain only a text string and encoding information. If you call (\$info, \$long) = GetFrame(\$id) for such a frame, \$info will contain the text string and \$long will contain the english name of the frame.

Example: getFrame("TIT2"); # returns

("Birdhouse In Your Soul", "Title/songname/content description")

Complex Frames

For more complex frames the returned \$info is a reference to a hash, where each entry of the hash decribes a part of the information found in the frame. The key of a hash entry contains the name of this part, the according value contains the information itself.

Example: getFrame("APIC"); # returns

( { "Description" => "Flood", 
    "MIME Type" => "/image/jpeg", 
    "Picture Type" => "Cover (front)",
    "_Data" => "..data of jpeg picture (binary).."
   },
 "Attached Picture");

Other Frames

Some frames are not supported at the moment, ie the data found in the frame is not returned in a descriptive way. But you can read the data of this frames (and also of all other frames too) in raw mode. Then the complete data field of the frame is returned, without any modifications. This means that the returned data will be almost binary data.

Example: getFrame("TIT2", 'raw'); # returns

("\\x00Birdhouse In Your Soul", "Title/songname/content description")

INTRO

@frames = keys %MP3::Tag::ID3v2::long_names; @other = (); @text = (); @complex = ();

foreach (@frames) { $data = MP3::Tag::ID3v2::what_data("", $_); if (ref $data) { if ($#$data == 0) { push @text, $_; } else { push @complex, $_; } } else { push @other, $_; } }

print "\n\n=head2 List of Simple Frames\n\nFollowing Frames are supported and return a single string (text). In the List you can find the frame IDs and the long names of the frames as returned by GetFrame():\n\n=over 4\n\n"; foreach (sort @text) { $long = $MP3::Tag::ID3v2::long_names{$_}; print "\n=item $_ : $long\n"; } print "\n=back\n\n";

print "\n\n=head2 List of Complex Frames\n\n"; print "Following frames are supported and return a reference to a hash. The list shows which keys can be found in the returned hash:\n"; print "\n=over 4\n\n"; foreach (sort @complex) { $long = $MP3::Tag::ID3v2::long_names{$_}; print "\n=item $_ : $long\n\n"; $data = MP3::Tag::ID3v2::what_data("", $_); print " Keys: ", join(", ",@$data), "\n"; } print "\n=back\n\n";

print "\n\n=head2 List of Other Frames\n\n"; print "Following frames are only supported in raw mode:\n"; print "\n=over 4\n\n"; foreach (sort @other) { $long = $MP3::Tag::ID3v2::long_names{$_}; print "\n=item $_ : $long\n"; } print "\n=back\n\n";

print <<END;

SEE ALSO

MP3::Tag, MP3::Tag::ID3v2

END

select($std); close POD;