#!/usr/bin/env python
#
# Copyright (c) 2002 Vivake Gupta (vivakeATomniscia.org). All rights reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
# USA
#
# This software is maintained by Vivake (vivakeATomniscia.org) and is available at:
# http://www.omniscia.org/~vivake/python/MP3Info.py
import struct
import string
def _from_synch_safe(synchsafe):
if isinstance(synchsafe, type(1)):
(b3, b2, b1, b0) = struct.unpack('!4b', struct.pack('!1i', synchsafe))
else:
while len(synchsafe) < 4:
synchsafe = (0,) + synchsafe
(b3, b2, b1, b0) = synchsafe
x = 256
return (((b3 * x + b2) * x + b1) * x + b0)
def _strip_zero(s):
start = 0
while start < len(s) and (s[start] == '\0' or s[start] == ' '):
start = start + 1
end = len(s) - 1
while end >= 0 and (s[end] == '\0' or s[end] == ' '):
end = end - 1
return s[start:end+1]
class ID3v2Frame:
def __init__(self, file, version):
self.name = ""
self.version = 0
self.padding = 0
self.size = 0
self.data = ""
self.flags = {}
self.f_tag_alter_preservation = 0
self.f_file_alter_preservation = 0
self.f_read_only = 0
self.f_compression = 0
self.f_encryption = 0
self.f_grouping_identity = 0
self.f_unsynchronization = 0
self.f_data_length_indicator = 0
if version == 2:
nameSize = 3
else:
nameSize = 4
self.name = file.read(nameSize)
self.version = version
if self.name == nameSize * '\0':
self.padding = 1
return
if self.name[0] < 'A' or self.name[0] > 'Z':
self.padding = 1
return
size = ()
if version == 2:
size = struct.unpack('!3b', file.read(3))
elif version == 3 or version == 4:
size = struct.unpack('!4b', file.read(4))
if version == 3: # abc00000 def00000
(flags,) = struct.unpack('!1b', file.read(1))
self.f_tag_alter_preservation = flags >> 7 & 1 #a
self.f_file_alter_preservation = flags >> 6 & 1 #b
self.f_read_only = flags >> 5 & 1 #c
(flags,) = struct.unpack('!1b', file.read(1))
self.f_compression = flags >> 7 & 1 #d
self.f_encryption = flags >> 6 & 1 #e
self.f_grouping_identity = flags >> 5 & 1 #f
elif version == 4: # 0abc0000 0h00kmnp
(flags,) = struct.unpack('!1b', file.read(1))
self.f_tag_alter_preservation = flags >> 6 & 1 #a
self.f_file_alter_preservation = flags >> 5 & 1 #b
self.f_read_only = flags >> 4 & 1 #c
(flags,) = struct.unpack('!1b', file.read(1))
self.f_grouping_identity = flags >> 6 & 1 #h
self.f_compression = flags >> 3 & 1 #k
self.f_encryption = flags >> 2 & 1 #m
self.f_unsynchronization = flags >> 1 & 1 #n
self.f_data_length_indicator = flags >> 0 & 1 #p
self.size = _from_synch_safe(size)
self.data = _strip_zero(file.read(self.size))
_genres = [
"Blues", "Classic Rock", "Country", "Dance", "Disco", "Funk", "Grunge",
"Hip-Hop", "Jazz", "Metal", "New Age", "Oldies", "Other", "Pop", "R&B",
"Rap", "Reggae", "Rock", "Techno", "Industrial", "Alternative", "Ska",
"Death Metal", "Pranks", "Soundtrack", "Euro-Techno", "Ambient", "Trip-Hop",
"Vocal", "Jazz+Funk", "Fusion", "Trance", "Classical", "Instrumental",
"Acid", "House", "Game", "Sound Clip", "Gospel", "Noise", "AlternRock",
"Bass", "Soul", "Punk", "Space", "Meditative", "Instrumental Pop",
"Instrumental Rock", "Ethnic", "Gothic", "Darkwave", "Techno-industrial",
"Electronic", "Pop-Folk", "Eurodance", "Dream", "Southern Rock", "Comedy",
"Cult", "Gangsta", "Top 40", "Christian Rap", "Pop/Funk", "Jungle",
"Native American", "Cabaret", "New Wave", "Psychadelic", "Rave",
"Showtunes", "Trailer", "Lo-Fi", "Tribal", "Acid Punk", "Acid Jazz",
"Polka", "Retro", "Musical", "Rock & Roll", "Hard Rock", "Folk",
"Folk/Rock", "National Folk", "Swing", "Fast-Fusion", "Bebob", "Latin",
"Revival", "Celtic", "Bluegrass", "Avantegarde", "Gothic Rock",
"Progressive Rock", "Psychedelic Rock", "Symphonic Rock", "Slow Rock",
"Big Band", "Chorus", "Easy Listening", "Acoustic", "Humour", "Speech",
"Chanson", "Opera", "Chamber Music", "Sonata", "Symphony", "Booty Bass",
"Primus", "Porn Groove", "Satire", "Slow Jam", "Club", "Tango", "Samba",
"Folklore", "Ballad", "Power Ballad", "Rythmic Soul", "Freestyle", "Duet",
"Punk Rock", "Drum Solo", "A capella", "Euro-House", "Dance Hall", "Goa",
"Drum & Bass", "Club House", "Hardcore", "Terror", "Indie", "BritPop",
"NegerPunk", "Polsk Punk", "Beat", "Christian Gangsta", "Heavy Metal",
"Black Metal", "Crossover", "Contemporary C", "Christian Rock", "Merengue",
"Salsa", "Thrash Metal", "Anime", "JPop", "SynthPop",
]
class ID3v1:
def __init__(self, file):
self.valid = 0
self.tags = { }
try:
file.seek(-128, 2)
except IOError:
pass
data = file.read(128)
if data[0:3] != 'TAG':
return
else:
self.valid = 1
self.tags['TT2'] = _strip_zero(data[ 3: 33])
self.tags['TP1'] = _strip_zero(data[33: 63])
self.tags['TAL'] = _strip_zero(data[63: 93])
self.tags['TYE'] = _strip_zero(data[93: 97])
self.tags['COM'] = _strip_zero(data[97:125])
if data[125] == '\0':
self.tags['TRK'] = ord(data[126])
try:
self.tags['TCO'] = _genres[ord(data[127])]
except IndexError:
self.tags['TCO'] = "(%i)" % ord(data[127])
class ID3v2:
def __init__(self, file):
self.valid = 0
self.tags = { }
self.header_size = 0
self.major_version = 0
self.minor_version = 0
self.f_unsynchronization = 0
self.f_extended_header = 0
self.f_experimental = 0
self.f_footer = 0
self.f_extended_header_zie = 0
self.f_extended_num_flag_bytes = 0
self.ef_update = 0
self.ef_crc = 0
self.ef_restrictions = 0
self.crc = 0
self.restrictions = 0
self.frames = []
self.tags = {}
file.seek(0, 0)
if file.read(3) != "ID3":
return
else:
self.valid = 1
(self.major_version, self.minor_version) = struct.unpack('!2b', file.read(2))
# abcd 0000
(flags,) = struct.unpack('!1b', file.read(1))
self.f_unsynchronization = flags >> 7 & 1 # a
self.f_extended_header = flags >> 6 & 1 # b
self.f_experimental = flags >> 5 & 1 # c
self.f_footer = flags >> 4 & 1 # d
self.header_size = _from_synch_safe(struct.unpack('!4b', file.read(4)))
while 1:
if file.tell() >= self.header_size:
break
frame = ID3v2Frame(file, self.major_version)
if frame.padding:
file.seek(self.header_size)
break
self.frames = self.frames + [frame]
self.tags[frame.name] = frame.data
_bitrates = [
[ # MPEG-2 & 2.5
[0,32,48,56, 64, 80, 96,112,128,144,160,176,192,224,256,None], # Layer 1
[0, 8,16,24, 32, 40, 48, 56, 64, 80, 96,112,128,144,160,None], # Layer 2
[0, 8,16,24, 32, 40, 48, 56, 64, 80, 96,112,128,144,160,None] # Layer 3
],
[ # MPEG-1
[0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,None], # Layer 1
[0,32,48,56, 64, 80, 96,112,128,160,192,224,256,320,384,None], # Layer 2
[0,32,40,48, 56, 64, 80, 96,112,128,160,192,224,256,320,None] # Layer 3
]
]
_samplerates = [
[ 11025, 12000, 8000, None], # MPEG-2.5
[ None, None, None, None], # reserved
[ 22050, 24000, 16000, None], # MPEG-2
[ 44100, 48000, 32000, None], # MPEG-1
]
_modes = [ "stereo", "joint stereo", "dual channel", "mono" ]
_mode_extensions = [
[ "4-31", "8-31", "12-31", "16-31" ],
[ "4-31", "8-31", "12-31", "16-31" ],
[ "", "IS", "MS", "IS+MS" ]
]
_emphases = [ "none", "50/15 ms", "reserved", "CCIT J.17" ]
_MP3_HEADER_SEEK_LIMIT = 8192
class MPEG:
def __init__(self, file):
self.valid = 0
file.seek(0, 2)
self.filesize = file.tell()
file.seek(0, 0)
self.version = 0
self.layer = 0
self.protection = 0
self.bitrate = 0
self.samplerate = 0
self.padding = 0
self.private = 0
self.mode = ""
self.mode_extension = ""
self.copyright = 0
self.original = 0
self.emphasis = ""
self.length = 0
offset, header = self._find_header(file)
if offset == -1 or header is None:
return
self._parse_header(header)
### offset + framelength will find another header. verify??
if not self.valid:
return
self._parse_xing(file)
def _find_header(self, file):
file.seek(0, 0)
amount_read = 0
# see if we get lucky with the first four bytes
amt = 4
while amount_read < _MP3_HEADER_SEEK_LIMIT:
header = file.read(amt)
if len(header) < amt:
# awfully short file. just give up.
return -1, None
amount_read = amount_read + len(header)
# on the next read, grab a lot more
amt = 500
# look for the sync byte
offset = string.find(header, chr(255))
if offset == -1:
continue
### maybe verify more sync bits in next byte?
if offset + 4 > len(header):
more = file.read(4)
if len(more) < 4:
# end of file. can't find a header
return -1, None
amount_read = amount_read + 4
header = header + more
return amount_read - len(header) + offset, header[offset:offset+4]
# couldn't find the header
return -1, None
def _parse_header(self, header):
# AAAAAAAA AAABBCCD EEEEFFGH IIJJKLMM
(bytes,) = struct.unpack('>i', header)
mpeg_version = (bytes >> 19) & 3 # BB 00 = MPEG2.5, 01 = res, 10 = MPEG2, 11 = MPEG1
layer = (bytes >> 17) & 3 # CC 00 = res, 01 = Layer 3, 10 = Layer 2, 11 = Layer 1
protection_bit = (bytes >> 16) & 1 # D 0 = protected, 1 = not protected
bitrate = (bytes >> 12) & 15 # EEEE 0000 = free, 1111 = bad
samplerate = (bytes >> 10) & 3 # F 11 = res
padding_bit = (bytes >> 9) & 1 # G 0 = not padded, 1 = padded
private_bit = (bytes >> 8) & 1 # H
mode = (bytes >> 6) & 3 # II 00 = stereo, 01 = joint stereo, 10 = dual channel, 11 = mono
mode_extension = (bytes >> 4) & 3 # JJ
copyright = (bytes >> 3) & 1 # K 00 = not copyrighted, 01 = copyrighted
original = (bytes >> 2) & 1 # L 00 = copy, 01 = original
emphasis = (bytes >> 0) & 3 # MM 00 = none, 01 = 50/15 ms, 10 = res, 11 = CCIT J.17
if mpeg_version == 0:
self.version = 2.5
elif mpeg_version == 2:
self.version = 2
elif mpeg_version == 3:
self.version = 1
else:
return
if layer > 0:
self.layer = 4 - layer
else:
return
self.protection = protection_bit
self.bitrate = _bitrates[mpeg_version & 1][self.layer - 1][bitrate]
self.samplerate = _samplerates[mpeg_version][samplerate]
if self.bitrate is None or self.samplerate is None:
return
self.padding = padding_bit
self.private = private_bit
self.mode = _modes[mode]
self.mode_extension = _mode_extensions[self.layer - 1][mode_extension]
self.copyright = copyright
self.original = original
self.emphasis = _emphases[emphasis]
if self.layer == 1:
self.framelength = (( 12 * (self.bitrate * 1000.0)/self.samplerate) + padding_bit) * 4
self.samplesperframe = 384.0
else:
self.framelength = ( 144 * (self.bitrate * 1000.0)/self.samplerate) + padding_bit
self.samplesperframe = 1152.0
self.length = int(round((self.filesize / self.framelength) * (self.samplesperframe / self.samplerate)))
self.valid = 1
def _parse_xing(self, file):
"""Parse the Xing-specific header.
For variable-bitrate (VBR) MPEG files, Xing includes a header which
can be used to approximate the (average) bitrate and the duration
of the file.
"""
file.seek(0, 0)
header = file.read(128)
i = string.find(header, 'Xing')
if i > 0:
(flags,) = struct.unpack('>i', header[i+4:i+8])
if flags & 3:
# flags says "frames" and "bytes" are present. use them.
(frames,) = struct.unpack('>i', header[i+8:i+12])
(bytes,) = struct.unpack('>i', header[i+12:i+16])
if self.samplerate:
self.length = int(round(frames * self.samplesperframe / self.samplerate))
self.bitrate = ((bytes * 8.0 / self.length) / 1000)
class MP3Info:
def __init__(self, file):
self.valid = 0
self.id3 = None
self.mpeg = None
id3 = ID3v1(file)
if id3.valid:
self.id3 = id3
id3 = ID3v2(file)
if id3.valid:
self.id3 = id3
self.mpeg = MPEG(file)
if self.id3 is None:
return
for tag in self.id3.tags.keys():
if tag == 'TT2' or tag == 'TIT2':
self.title = self.id3.tags[tag]
elif tag == 'TP1' or tag == 'TPE1':
self.artist = self.id3.tags[tag]
elif tag == 'TRK' or tag == 'TRCK':
self.track = self.id3.tags[tag]
elif tag == 'TYE' or tag == 'TYER':
self.year = self.id3.tags[tag]
elif tag == 'COM' or tag == 'COMM':
self.comment = self.id3.tags[tag]
elif tag == 'TCM':
self.composer = self.id3.tags[tag]
elif tag == 'TAL' or tag == 'TALB':
self.album = self.id3.tags[tag]
elif tag == 'TPA':
self.disc = self.id3.tags[tag]
elif tag == 'TCO' or tag == 'TCON':
self.genre = self.id3.tags[tag]
if self.genre and self.genre[0] == '(' and self.genre[-1] == ')':
try:
self.genre = _genres[int(self.genre[1:-1])]
except IndexError:
self.genre = ""
elif tag == 'TEN' or tag == 'TENC':
self.encoder = self.id3.tags[tag]
if __name__ == '__main__':
import sys
i = MP3Info(open(sys.argv[1], 'rb'))
print i.id3.tags
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