NAME
MPEG::MP3Info - Manipulate / fetch info from MP3 audio files
SYNOPSIS
#!perl -w
use MPEG::MP3Info;
my $file = 'Pearls_Before_Swine.mp3';
set_mp3tag($file, 'Pearls Before Swine', q"77's",
'Sticks and Stones', '1990', q"(c) 1990 77's LTD.", 'rock & roll');
my $tag = get_mp3tag($file) or die "No TAG info";
$tag->{GENRE} = 'rock';
set_mp3tag($file, $tag);
my $info = get_mp3info($file);
printf "$file length is %d:%d", $info->{MM}, $info->{SS};
DESCRIPTION
- use_winamp_genres()
-
Puts WinAmp genres into
@mp3_genres
and%mp3_genres
.You can import the data structures with one of:
use MPEG::MP3Info qw(:genres); use MPEG::MP3Info qw(:DEFAULT :genres); use MPEG::MP3Info qw(:all);
- remove_mp3tag (FILE)
-
Removes last 128 bytes from file if those last 128 bytes begin with the text `TAG'. File will be 128 bytes shorter. Returns undef if no existing TAG found, 1 on successful removal of TAG.
- set_mp3tag (FILE, TITLE, ARTIST, ALBUM, YEAR, COMMENT, GENRE [, TRACKNUM])
- set_mp3tag (FILE, $HASHREF)
-
Adds/changes tag information in an MP3 audio file. Will clobber any existing information in file.
Fields are TITLE, ARTIST, ALBUM, YEAR, COMMENT, GENRE. All fields have a 30-byte limit, except for YEAR, which has a four-byte limit, and GENRE, which is one byte in the file. The GENRE passed in the function is a case-insensitive text string representing a genre found in
@mp3_genres
.Will accept either a list of values, or a hashref of the type returned by
get_mp3tag
.If TRACKNUM is present (for ID3v1.1), then the COMMENT field can only be 28 bytes.
ID3v2 support will come eventually.
- get_mp3tag (FILE [, VERSION, RAW_V2])
-
Returns hash reference containing tag information in MP3 file. Same info as described in
set_mp3tag
.If VERSION is
1
, the information is taken from the ID3v1 tag (if present). If VERSION is2
, the information is taken from the ID3v2 tag (if present). If VERSION is not supplied, the ID3v1 tag is read if present, and then, if present, the ID3v2 tag information will override any existing ID3v1 tag info.If the ID3v2 version is older than ID3v2.3.0, it will not be read (and a warning will be issued if -w is on).
If RAW_V2 is false or not supplied and VERSION is
2
, only the tags corresponding to ID3v1 tags are returned, with the same keys in the returned hashref.If RAW_V2 is true and VERSION is
2
,get_mp3tag
will return a hash of tag four-character IDs and their data. Tag IDs and their meanings are in the global hash (not exported)%v2_tag_names
.my $tag = get_mp3tag('mysong.mp3', 2, 1); # ID3v2, raw ID3v2 tags for (keys %$tag) { printf "%s => %s\n", $MPEG::MP3Info::v2_tag_names{$_}, $tag->{$_}; }
- get_mp3info (FILE)
-
Returns hash reference containing file information for MP3 file. This data cannot be changed. Returned data includes MP3 version (VERSION), total time in minutes (MM) and seconds (SS), boolean for STEREO, MPEG layer (LAYER), BITRATE, MODE, boolean for COPYRIGHT, and FREQUENCY.
Variable bitrates not yet supported. See "TODO".
TROUBLESHOOTING
If you find a bug, please send me a patch. If you cannot figure out why it does not work for you, please put the MP3 file in a place where I can get it (preferably via FTP) and send me mail regarding where I can get the file, with a detailed description of the problem.
If I download the file, after debugging the problem I will not keep the MP3 file if it is not legal for me to have it. Just let me know if it is legal for me ot keep it or not.
TODO
- ID3v2 Support
-
First go at adding support for reading ID3v2 tags. Still need to do more, such as using Compress::Zlib to decompress compressed tags. But until I see this in use, I won't bother. I might not be able to support Unicode at all, until Perl supports 16-bit Unicode. If something does not work properly with reading, follow the instructions above for troubleshooting.
Still need to add support for writing ID3v2 tags, and work on API a bit.
- Variable Bitrate MP3s
-
Get correct length in MM:SS ... anything other problems relating to this? Need algorithm for it. If someone supplies it, I'd be happy to implement it.
HISTORY
- v0.71, Thursday, July 8, 1999
-
Several fixes to ID3v2 support unpack unsigned instead of signed, don't bail out after 4096-byte offsets on long ID3v2 headers. Thanks much to Matthew Sachs.
- v0.70, Saturday, July 3, 1999
-
Added preliminary ID3v2 reading support in
get_mp3tag
. Thanks much to Tom Brown. - v0.64, Thursday, July 1, 1999
-
Found bug in checking TRACKNUM parameter, used \d instead of \d+. Only gives spurious warnings, doesn't affect anything else.
Cleaned up a bit, prepare for impending ID3v2 support.
NOTE: truncate() broken in some builds of ActivePerl (517, maybe others). No changes to module to fix problem. (Brian Goodwin)
- v0.63, Friday, April 30, 1999
-
Added ID3v1.1 support. (Trond Michelsen, Pass F. B. Travis)
Added 255 (\xFF) as default genre. (Andrew Phillips)
I think I fixed bug relating to spaces in ID3v2 headers. (Tom Brown)
- v0.62, Sunday, March 7, 1999
-
Doc updates.
Fix small unnoticable bug where ID3v2 offset is tag size plus 10, not just tag size.
Not publickly released.
- v0.61, Monday, March 1, 1999
-
Fixed problem of not removing nulls on return from
get_mp3tag
(was using spaces for padding before ... now trailing whitespace and all nulls are removed before returning tag info).Made tests more extensive (more for my own sanity when making all these changes than to make sure it works on other platforms and machines :).
- v0.60, Sunday, February 28, 1999
-
Cleaned up a lot of stuff, added more comments, made
get_mp3info
much faster and much more reliable, and added recognition of ID3v2 headers. (Tom Brown) - v0.52, Sunday, February 21, 1999
-
Fixed problem in
get_mp3tag
that changed value of$_
in caller (Todd Hanneken). - v0.51, Saturday, February 20, 1999
-
Fixed problem with
%winamp_genres
having the wrong numbers (Matthew Sachs). - v0.50, Friday, February 19, 1999
-
Added
remove_mp3tag
. Addeed VERSION to the hash returned byget_mp3info
, and fixed a bug where STEREO was not being set correctly.Export all genre data structures on request. Added
use_winamp_genres
to use WinAmp genres. (Roland Steinbach)Added a
$MPEG::MP3Info::try_harder
variable that will try harder to find the MP3 header in a file. False by default. Can take a long time to fail, but should find most headers at any offets if set to true.Thanks to Matthew Sachs for his input and fixes, and for mp3tools.
- v0.20, Saturday, October 17, 1998
-
Changed name from
MPEG::MP3Tag
toMPEG::MP3Info
, because it does more than just TAG stuff now.Made header stuff even more reliable. Lots of help and testing from Meng Weng Wong again. :-)
- v0.13, Thursday, October 8, 1998
-
Had some problems with header verification, got some code from Predrag Supurovic with his mpgtools. Great stuff. Also did some looping to find a header if it is not in the "right" place. I did what I think it is a smart way to do it, since some files have the header as far down as 2 kbytes into the file. First, I look at position 0, then at position 36 (a position where I have found many headers), then I start at 0 again and jump in 128-byte chunks. Once I do that a bunch of times, I go back at the beginning and try at 0 and go ahead in 1-byte chunks for a bunch more times.
If you have an MP3 that has the header begin at an odd place like byte 761, then I suggest you strip out the junk before the header begins. :-)
- v0.12, Friday, October 2, 1998
-
Added
get_mp3info
. Thanks again to mp3tool source from Johann Lindvall, because I basically stole it straight (after converting it from C to Perl, of course).I did everything I could to find the header info, but if anyone has valid MP3 files that are not recognized, or has suggestions for improvement of the algorithms, let me know.
- v0.04, Tuesday, September 29, 1998
-
Changed a few things, replaced a regex with an
unpack
. (Meng Weng Wong) - v0.03, Tuesday, September 8, 1998
-
First public release.
THANKS
Johann Lindvall, Meng Weng Wong <mengwong@pobox.com>, Predrag Supurovic <mpgtools@dv.co.yu>, Matthew Sachs <matthewg@zevils.com>, Peter Kovacs <kovacsp@egr.uri.edu>, Roland Steinbach <roland@support-system.com>, Todd Hanneken <thanneken@hds.harvard.edu>, Tom Brown <thecap@usa.net>, Andrew Phillips <asp@wasteland.org>, Trond Michelsen <mike@crusaders.no>, Pass F. B. Travis <pftravis@bellsouth.net>, Vittorio Bertola <v.bertola@vitaminic.com>, Brian Goodwin <brian@fuddmain.com>.
AUTHOR AND COPYRIGHT
Chris Nandor <pudge@pobox.com>, http://pudge.net/
Copyright (c) 1999 Chris Nandor. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the Artistic License, distributed with Perl.
SEE ALSO
- mp3tools
-
http://www.zevils.com/linux/mp3tools/
- mpgtools
-
http://www.dv.co.yu/mp3list/mpgtools.htm http://www.dv.co.yu/mp3list/mpeghdr.htm
- mp3tool
-
http://www.dtek.chalmers.se/~d2linjo/mp3/mp3tool.html
- ID3v2
-
http://www.id3.org/
VERSION
v0.71, Saturday, July 3, 1999