Info(3) User Contributed Perl Documentation Info(3)NAMEMP3::Info - Manipulate / fetch info from MP3 audio files
SYNOPSIS
#!perl -w
use MP3::Info;
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\n", $info->{MM}, $info->{SS};
my $mp3 = new MP3::Info $file;
$mp3->title('Perls Before Swine');
printf "$file length is %s, title is %s\n",
$mp3->time, $mp3->title;
DESCRIPTION
$mp3 = MP3::Info->new(FILE)
OOP interface to the rest of the module. The same keys available
via get_mp3info and get_mp3tag are available via the returned
object (using upper case or lower case; but note that all-caps
"VERSION" will return the module version, not the MP3 version).
Passing a value to one of the methods will set the value for that
tag in the MP3 file, if applicable.
use_mp3_utf8([STATUS])
Tells MP3::Info to (or not) return TAG info in UTF-8. TRUE is 1,
FALSE is 0. Default is TRUE, if available.
Will only be able to turn it on if Encode is available. ID3v2 tags
will be converted to UTF-8 according to the encoding specified in
each tag; ID3v1 tags will be assumed Latin-1 and converted to
UTF-8.
Function returns status (TRUE/FALSE). If no argument is supplied,
or an unaccepted argument is supplied, function merely returns
status.
This function is not exported by default, but may be exported with
the ":utf8" or ":all" export tag.
use_winamp_genres()
Puts WinAmp genres into @mp3_genres and %mp3_genres (adds 68
additional genres to the default list of 80). This is a separate
function because these are non-standard genres, but they are
included because they are widely used.
You can import the data structures with one of:
use MP3::Info qw(:genres);
use MP3::Info qw(:DEFAULT :genres);
use MP3::Info qw(:all);
remove_mp3tag (FILE [, VERSION, BUFFER])
Can remove ID3v1 or ID3v2 tags. VERSION should be 1 for ID3v1 (the
default), 2 for ID3v2, and "ALL" for both.
For ID3v1, removes last 128 bytes from file if those last 128 bytes
begin with the text 'TAG'. File will be 128 bytes shorter.
For ID3v2, removes ID3v2 tag. Because an ID3v2 tag is at the
beginning of the file, we rewrite the file after removing the tag
data. The buffer for rewriting the file is 4MB. BUFFER (in bytes)
ca change the buffer size.
Returns the number of bytes removed, or -1 if no tag removed, or
undef if there is an error.
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 may come eventually. Note that if you set a tag on a
file with ID3v2, the set tag will be for ID3v1[.1] only, and if you
call "get_mp3tag" on the file, it will show you the (unchanged)
ID3v2 tags, unless you specify ID3v1.
get_mp3tag (FILE [, VERSION, RAW_V2, APE2])
Returns hash reference containing tag information in MP3 file. The
keys returned are the same as those supplied for "set_mp3tag",
except in the case of RAW_V2 being set.
If VERSION is 1, the information is taken from the ID3v1 tag (if
present). If VERSION is 2, the information is taken from the ID3v2
tag (if present). If VERSION is not supplied, or is false, the
ID3v1 tag is read if present, and then, if present, the ID3v2 tag
information will override any existing ID3v1 tag info.
If RAW_V2 is 1, the raw ID3v2 tag data is returned, without any
manipulation of text encoding. The key name is the same as the
frame ID (ID to name mappings are in the global %v2_tag_names).
If RAW_V2 is 2, the ID3v2 tag data is returned, manipulating for
Unicode if necessary, etc. It also takes multiple values for a
given key (such as comments) and puts them in an arrayref.
If APE is 1, an APE tag will be located before all other tags.
If the ID3v2 version is older than ID3v2.2.0 or newer than
ID3v2.4.0, it will not be read.
Strings returned will be in Latin-1, unless UTF-8 is specified
(use_mp3_utf8), (unless RAW_V2 is 1).
Also returns a TAGVERSION key, containing the ID3 version used for
the returned data (if TAGVERSION argument is 0, may contain two
versions).
get_mp3info (FILE)
Returns hash reference containing file information for MP3 file.
This data cannot be changed. Returned data:
VERSION MPEG audio version (1, 2, 2.5)
LAYER MPEG layer description (1, 2, 3)
STEREO boolean for audio is in stereo
VBR boolean for variable bitrate
BITRATE bitrate in kbps (average for VBR files)
FREQUENCY frequency in kHz
SIZE bytes in audio stream
OFFSET bytes offset that stream begins
SECS total seconds
MM minutes
SS leftover seconds
MS leftover milliseconds
TIME time in MM:SS
COPYRIGHT boolean for audio is copyrighted
PADDING boolean for MP3 frames are padded
MODE channel mode (0 = stereo, 1 = joint stereo,
2 = dual channel, 3 = single channel)
FRAMES approximate number of frames
FRAME_LENGTH approximate length of a frame
VBR_SCALE VBR scale from VBR header
On error, returns nothing and sets $@.
TROUBLESHOOTING
If you find a bug, please send me a patch (see the project page in "SEE
ALSO"). 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, or
HTTP, or .Mac iDisk) 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 to keep it or not.
TODO
ID3v2 Support
Still need to do more for reading tags, such as using
Compress::Zlib to decompress compressed tags. But until I see this
in use more, I won't bother. If something does not work properly
with reading, follow the instructions above for troubleshooting.
ID3v2 writing is coming soon.
Get data from scalar
Instead of passing a file spec or filehandle, pass the data itself.
Would take some work, converting the seeks, etc.
Padding bit ?
Do something with padding bit.
Test suite
Test suite could use a bit of an overhaul and update. Patches very
welcome.
· Revamp getset.t. Test all the various get_mp3tag args.
· Test Unicode.
· Test OOP API.
· Test error handling, check more for missing files, bad MP3s,
etc.
Other VBR
Right now, only Xing VBR is supported.
THANKS
Edward Allen, Vittorio Bertola, Michael Blakeley, Per Bolmstedt, Tony
Bowden, Tom Brown, Sergio Camarena, Chris Dawson, Kevin Deane-Freeman,
Anthony DiSante, Luke Drumm, Kyle Farrell, Jeffrey Friedl, brian d foy,
Ben Gertzfield, Brian Goodwin, Andy Grundman, Todd Hanneken, Todd
Harris, Woodrow Hill, Kee Hinckley, Roman Hodek, Ilya Konstantinov,
Peter Kovacs, Johann Lindvall, Alex Marandon, Peter Marschall, michael,
Trond Michelsen, Dave O'Neill, Christoph Oberauer, Jake Palmer, Andrew
Phillips, David Reuteler, John Ruttenberg, Matthew Sachs, scfc_de,
Hermann Schwaerzler, Chris Sidi, Roland Steinbach, Brian S. Stephan,
Stuart, Dan Sully, Jeffery Sumler, Predrag Supurovic, Bogdan Surdu,
Pierre-Yves Thoulon, tim, Pass F. B. Travis, Tobias Wagener, Ronan
Waide, Andy Waite, Ken Williams, Ben Winslow, Meng Weng Wong, Justin
Fletcher.
CURRENT AUTHOR
Dan Sully <daniel | at | cpan.org> & Logitech.
AUTHOR EMERITUS
Chris Nandor <pudge@pobox.com>, http://pudge.net/
COPYRIGHT AND LICENSE
Copyright (c) 2006-2008 Dan Sully & Logitech. All rights reserved.
Copyright (c) 1998-2005 Chris Nandor. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
SEE ALSO
Logitech/Slim Devices
http://www.slimdevices.com/
mp3tools
http://www.zevils.com/linux/mp3tools/
mpgtools
http://www.dv.co.yu/mpgscript/mpgtools.htm
http://www.dv.co.yu/mpgscript/mpeghdr.htm
mp3tool
http://www.dtek.chalmers.se/~d2linjo/mp3/mp3tool.html
ID3v2
http://www.id3.org/
Xing Variable Bitrate
http://www.xingtech.com/support/partner_developer/mp3/vbr_sdk/
MP3Ext
http://rupert.informatik.uni-stuttgart.de/~mutschml/MP3ext/
Xmms
http://www.xmms.org/
perl v5.16.2 2008-11-09 Info(3)
