class __GIF__(ImageMetrics):
HEADER = Con.Struct('header',
Con.Const(Con.String('gif', 3), 'GIF'),
Con.String('version', 3))
SCREEN_DESCRIPTOR = Con.Struct('logical_screen_descriptor',
Con.ULInt16('width'),
Con.ULInt16('height'),
Con.Embed(
Con.BitStruct('packed_fields',
Con.Flag('global_color_table'),
Con.Bits('color_resolution', 3),
Con.Flag('sort'),
Con.Bits('global_color_table_size', 3))),
Con.Byte('background_color_index'),
Con.Byte('pixel_aspect_ratio'))
def __init__(self, width, height, color_count):
ImageMetrics.__init__(self, width, height, 8, color_count,
u'image/gif')
@classmethod
def parse(cls, file):
try:
header = cls.HEADER.parse_stream(file)
descriptor = cls.SCREEN_DESCRIPTOR.parse_stream(file)
return __GIF__(descriptor.width, descriptor.height,
2 ** (descriptor.global_color_table_size + 1))
except Con.ConstError:
raise InvalidGIF(_(u'Invalid GIF'))
class SpeexAudio(VorbisAudio):
"""An Ogg Speex audio file."""
SUFFIX = "spx"
NAME = SUFFIX
DEFAULT_COMPRESSION = "8"
COMPRESSION_MODES = tuple([str(i) for i in range(0, 11)])
BINARIES = ("speexenc", "speexdec")
REPLAYGAIN_BINARIES = tuple()
SPEEX_HEADER = Con.Struct('speex_header', Con.String('speex_string', 8),
Con.String('speex_version', 20),
Con.ULInt32('speex_version_id'),
Con.ULInt32('header_size'),
Con.ULInt32('sampling_rate'),
Con.ULInt32('mode'),
Con.ULInt32('mode_bitstream_version'),
Con.ULInt32('channels'), Con.ULInt32('bitrate'),
Con.ULInt32('frame_size'), Con.ULInt32('vbr'),
Con.ULInt32('frame_per_packet'),
Con.ULInt32('extra_headers'),
Con.ULInt32('reserved1'),
Con.ULInt32('reserved2'))
def __init__(self, filename):
"""filename is a plain string."""
AudioFile.__init__(self, filename)
try:
self.__read_metadata__()
except IOError, msg:
raise InvalidSpeex(str(msg))
class Musepack8StreamReader:
"""An object for parsing Musepack SV8 streams."""
NUT_HEADER = Con.Struct('nut_header',
Con.String('key', 2),
NutValue('length'))
def __init__(self, stream):
"""Initialized with a file object."""
self.stream = stream
def packets(self):
"""Yields a set of (key, data) tuples."""
import string
UPPERCASE = frozenset(string.ascii_uppercase)
while (True):
try:
frame_header = self.NUT_HEADER.parse_stream(self.stream)
except Con.core.FieldError:
break
if (not frozenset(frame_header.key).issubset(UPPERCASE)):
break
yield (frame_header.key,
self.stream.read(frame_header.length -
len(self.NUT_HEADER.build(frame_header))))
class VorbisAudio(AudioFile):
"""An Ogg Vorbis file."""
SUFFIX = "ogg"
NAME = SUFFIX
DEFAULT_COMPRESSION = "3"
COMPRESSION_MODES = tuple([str(i) for i in range(0, 11)])
BINARIES = ("oggenc", "oggdec")
REPLAYGAIN_BINARIES = ("vorbisgain", )
OGG_IDENTIFICATION = Con.Struct(
"ogg_id", Con.ULInt32("vorbis_version"), Con.Byte("channels"),
Con.ULInt32("sample_rate"), Con.ULInt32("bitrate_maximum"),
Con.ULInt32("bitrate_nominal"), Con.ULInt32("bitrate_minimum"),
Con.Embed(
Con.BitStruct("flags", Con.Bits("blocksize_0", 4),
Con.Bits("blocksize_1", 4))), Con.Byte("framing"))
COMMENT_HEADER = Con.Struct("comment_header", Con.Byte("packet_type"),
Con.String("vorbis", 6))
def __init__(self, filename):
"""filename is a plain string."""
AudioFile.__init__(self, filename)
try:
self.__read_metadata__()
except IOError, msg:
raise InvalidVorbis(str(msg))
class AuAudio(AudioFile):
"""A Sun AU audio file."""
SUFFIX = "au"
NAME = SUFFIX
AU_HEADER = Con.Struct('header',
Con.Const(Con.String('magic_number', 4), '.snd'),
Con.UBInt32('data_offset'),
Con.UBInt32('data_size'),
Con.UBInt32('encoding_format'),
Con.UBInt32('sample_rate'), Con.UBInt32('channels'))
def __init__(self, filename):
AudioFile.__init__(self, filename)
try:
f = file(filename, 'rb')
except IOError, msg:
raise InvalidAU(str(msg))
try:
header = AuAudio.AU_HEADER.parse_stream(f)
if (header.encoding_format not in (2, 3, 4)):
raise InvalidFile(_(u"Unsupported Sun AU encoding format"))
self.__bits_per_sample__ = {
2: 8,
3: 16,
4: 24
}[header.encoding_format]
self.__channels__ = header.channels
self.__sample_rate__ = header.sample_rate
self.__total_frames__ = header.data_size / \
(self.__bits_per_sample__ / 8) / \
self.__channels__
self.__data_offset__ = header.data_offset
self.__data_size__ = header.data_size
except Con.ConstError:
raise InvalidFile(_(u"Invalid Sun AU header"))
except Con.FieldError:
raise InvalidAU(_(u"Invalid Sun AU header"))
class __BMP__(ImageMetrics):
HEADER = Con.Struct('bmp_header',
Con.Const(Con.String('magic_number', 2), 'BM'),
Con.ULInt32('file_size'),
Con.ULInt16('reserved1'),
Con.ULInt16('reserved2'),
Con.ULInt32('bitmap_data_offset'))
INFORMATION = Con.Struct('bmp_information',
Con.ULInt32('header_size'),
Con.ULInt32('width'),
Con.ULInt32('height'),
Con.ULInt16('color_planes'),
Con.ULInt16('bits_per_pixel'),
Con.ULInt32('compression_method'),
Con.ULInt32('image_size'),
Con.ULInt32('horizontal_resolution'),
Con.ULInt32('vertical_resolution'),
Con.ULInt32('colors_used'),
Con.ULInt32('important_colors_used'))
def __init__(self, width, height, bits_per_pixel, color_count):
ImageMetrics.__init__(self, width, height, bits_per_pixel, color_count,
u'image/x-ms-bmp')
@classmethod
def parse(cls, file):
try:
header = cls.HEADER.parse_stream(file)
information = cls.INFORMATION.parse_stream(file)
return __BMP__(information.width, information.height,
information.bits_per_pixel,
information.colors_used)
except Con.ConstError:
raise InvalidBMP(_(u'Invalid BMP'))
class MusepackAudio(ApeTaggedAudio, AudioFile):
"""A Musepack audio file."""
SUFFIX = "mpc"
NAME = SUFFIX
DEFAULT_COMPRESSION = "standard"
COMPRESSION_MODES = ("thumb", "radio", "standard", "extreme", "insane")
###Musepack SV7###
#BINARIES = ('mppdec','mppenc')
###Musepack SV8###
BINARIES = ('mpcdec', 'mpcenc')
MUSEPACK8_HEADER = Con.Struct('musepack8_header',
Con.UBInt32('crc32'),
Con.Byte('bitstream_version'),
NutValue('sample_count'),
NutValue('beginning_silence'),
Con.Embed(Con.BitStruct(
'flags',
Con.Bits('sample_frequency', 3),
Con.Bits('max_used_bands', 5),
Con.Bits('channel_count', 4),
Con.Flag('mid_side_used'),
Con.Bits('audio_block_frames', 3))))
#not sure about some of the flag locations
#Musepack 7's header is very unusual
MUSEPACK7_HEADER = Con.Struct('musepack7_header',
Con.Const(Con.String('signature', 3), 'MP+'),
Con.Byte('version'),
Con.ULInt32('frame_count'),
Con.ULInt16('max_level'),
Con.Embed(
Con.BitStruct('flags',
Con.Bits('profile', 4),
Con.Bits('link', 2),
Con.Bits('sample_frequency', 2),
Con.Flag('intensity_stereo'),
Con.Flag('midside_stereo'),
Con.Bits('maxband', 6))),
Con.ULInt16('title_gain'),
Con.ULInt16('title_peak'),
Con.ULInt16('album_gain'),
Con.ULInt16('album_peak'),
Con.Embed(
Con.BitStruct('more_flags',
Con.Bits('unused1', 16),
Con.Bits('last_frame_length_low', 4),
Con.Flag('true_gapless'),
Con.Bits('unused2', 3),
Con.Flag('fast_seeking'),
Con.Bits('last_frame_length_high', 7))),
Con.Bytes('unknown', 3),
Con.Byte('encoder_version'))
def __init__(self, filename):
"""filename is a plain string."""
AudioFile.__init__(self, filename)
f = file(filename, 'rb')
try:
if (f.read(4) == 'MPCK'): # a Musepack 8 stream
for (key, packet) in Musepack8StreamReader(f).packets():
if (key == 'SH'):
header = MusepackAudio.MUSEPACK8_HEADER.parse(packet)
self.__sample_rate__ = (44100, 48000,
37800, 32000)[
header.sample_frequency]
self.__total_frames__ = header.sample_count
self.__channels__ = header.channel_count + 1
break
elif (key == 'SE'):
raise InvalidFile(_(u'No Musepack header found'))
else: # a Musepack 7 stream
f.seek(0, 0)
try:
header = MusepackAudio.MUSEPACK7_HEADER.parse_stream(f)
except Con.ConstError:
raise InvalidFile(_(u'Musepack signature incorrect'))
header.last_frame_length = \
(header.last_frame_length_high << 4) | \
header.last_frame_length_low
self.__sample_rate__ = (44100, 48000,
37800, 32000)[header.sample_frequency]
self.__total_frames__ = (((header.frame_count - 1) * 1152) +
header.last_frame_length)
self.__channels__ = 2
finally:
f.close()
@classmethod
def from_pcm(cls, filename, pcmreader, compression=None):
"""Encodes a new file from PCM data.
Takes a filename string, PCMReader object
and optional compression level string.
Encodes a new audio file from pcmreader's data
at the given filename with the specified compression level
and returns a new MusepackAudio object."""
import tempfile
import bisect
if (str(compression) not in cls.COMPRESSION_MODES):
compression = cls.DEFAULT_COMPRESSION
if ((pcmreader.channels > 2) or
(pcmreader.sample_rate not in (44100, 48000, 37800, 32000)) or
(pcmreader.bits_per_sample != 16)):
pcmreader = PCMConverter(
pcmreader,
sample_rate=[32000, 32000, 37800, 44100, 48000][bisect.bisect(
[32000, 37800, 44100, 48000], pcmreader.sample_rate)],
channels=min(pcmreader.channels, 2),
bits_per_sample=16)
f = tempfile.NamedTemporaryFile(suffix=".wav")
w = WaveAudio.from_pcm(f.name, pcmreader)
try:
return cls.__from_wave__(filename, f.name, compression)
finally:
del(w)
f.close()
#While Musepack needs to pipe things through WAVE,
#not all WAVEs are acceptable.
#Use the *_pcm() methods first.
def __to_wave__(self, wave_filename):
devnull = file(os.devnull, "wb")
try:
sub = subprocess.Popen([BIN['mpcdec'],
self.filename,
wave_filename],
stdout=devnull,
stderr=devnull)
#FIXME - small files (~5 seconds) result in an error by mpcdec,
#even if they decode correctly.
#Not much we can do except try to workaround its bugs.
if (sub.wait() not in [0, 250]):
raise DecodingError()
finally:
devnull.close()
@classmethod
def __from_wave__(cls, filename, wave_filename, compression=None):
if (str(compression) not in cls.COMPRESSION_MODES):
compression = cls.DEFAULT_COMPRESSION
#mppenc requires files to end with .mpc for some reason
if (not filename.endswith(".mpc")):
import tempfile
actual_filename = filename
tempfile = tempfile.NamedTemporaryFile(suffix=".mpc")
filename = tempfile.name
else:
actual_filename = tempfile = None
###Musepack SV7###
#sub = subprocess.Popen([BIN['mppenc'],
# "--silent",
# "--overwrite",
# "--%s" % (compression),
# wave_filename,
# filename],
# preexec_fn=ignore_sigint)
###Musepack SV8###
sub = subprocess.Popen([BIN['mpcenc'],
"--silent",
"--overwrite",
"--%s" % (compression),
wave_filename,
filename])
if (sub.wait() == 0):
if (tempfile is not None):
filename = actual_filename
f = file(filename, 'wb')
tempfile.seek(0, 0)
transfer_data(tempfile.read, f.write)
f.close()
tempfile.close()
return MusepackAudio(filename)
else:
if (tempfile is not None):
tempfile.close()
raise EncodingError(u"error encoding file with mpcenc")
@classmethod
def is_type(cls, file):
"""Returns True if the given file object describes this format.
Takes a seekable file pointer rewound to the start of the file."""
header = file.read(4)
###Musepack SV7###
#return header == 'MP+\x07'
###Musepack SV8###
return (header == 'MP+\x07') or (header == 'MPCK')
def sample_rate(self):
"""Returns the rate of the track's audio as an integer number of Hz."""
return self.__sample_rate__
def total_frames(self):
"""Returns the total PCM frames of the track as an integer."""
return self.__total_frames__
def channels(self):
"""Returns an integer number of channels this track contains."""
return self.__channels__
def bits_per_sample(self):
"""Returns an integer number of bits-per-sample this track contains."""
return 16
def lossless(self):
"""Returns False."""
return False
class ID3v1Comment(MetaData, list):
"""A complete ID3v1 tag."""
ID3v1 = Con.Struct("id3v1", Con.Const(Con.String("identifier", 3), 'TAG'),
Con.String("song_title", 30), Con.String("artist", 30),
Con.String("album", 30), Con.String("year", 4),
Con.String("comment", 28), Con.Padding(1),
Con.Byte("track_number"), Con.Byte("genre"))
ID3v1_NO_TRACKNUMBER = Con.Struct(
"id3v1_notracknumber", Con.Const(Con.String("identifier", 3), 'TAG'),
Con.String("song_title", 30), Con.String("artist", 30),
Con.String("album", 30), Con.String("year", 4),
Con.String("comment", 30), Con.Byte("genre"))
ATTRIBUTES = [
'track_name', 'artist_name', 'album_name', 'year', 'comment',
'track_number'
]
@classmethod
def read_id3v1_comment(cls, mp3filename):
"""Reads a ID3v1Comment data from an MP3 filename.
Returns a (song title, artist, album, year, comment, track number)
tuple.
If no ID3v1 tag is present, returns a tuple with those fields blank.
All text is in unicode.
If track number is -1, the id3v1 comment could not be found.
"""
mp3file = file(mp3filename, "rb")
try:
mp3file.seek(-128, 2)
try:
id3v1 = ID3v1Comment.ID3v1.parse(mp3file.read())
except Con.adapters.PaddingError:
mp3file.seek(-128, 2)
id3v1 = ID3v1Comment.ID3v1_NO_TRACKNUMBER.parse(mp3file.read())
id3v1.track_number = 0
except Con.ConstError:
return tuple([u""] * 5 + [-1])
field_list = (id3v1.song_title, id3v1.artist, id3v1.album,
id3v1.year, id3v1.comment)
return tuple(
map(lambda t: t.rstrip('\x00').decode('ascii', 'replace'),
field_list) + [id3v1.track_number])
finally:
mp3file.close()
@classmethod
def build_id3v1(cls, song_title, artist, album, year, comment,
track_number):
"""Turns fields into a complete ID3v1 binary tag string.
All fields are unicode except for track_number, an int."""
def __s_pad__(s, length):
if (len(s) < length):
return s + chr(0) * (length - len(s))
else:
s = s[0:length].rstrip()
return s + chr(0) * (length - len(s))
c = Con.Container()
c.identifier = 'TAG'
c.song_title = __s_pad__(song_title.encode('ascii', 'replace'), 30)
c.artist = __s_pad__(artist.encode('ascii', 'replace'), 30)
c.album = __s_pad__(album.encode('ascii', 'replace'), 30)
c.year = __s_pad__(year.encode('ascii', 'replace'), 4)
c.comment = __s_pad__(comment.encode('ascii', 'replace'), 28)
c.track_number = int(track_number)
c.genre = 0
return ID3v1Comment.ID3v1.build(c)
def __init__(self, metadata):
"""Initialized with a read_id3v1_comment tuple.
Fields are (title,artist,album,year,comment,tracknum)"""
list.__init__(self, metadata)
def supports_images(self):
"""Returns False."""
return False
#if an attribute is updated (e.g. self.track_name)
#make sure to update the corresponding list item
def __setattr__(self, key, value):
if (key in self.ATTRIBUTES):
if (key != 'track_number'):
self[self.ATTRIBUTES.index(key)] = value
else:
self[self.ATTRIBUTES.index(key)] = int(value)
elif (key in MetaData.__FIELDS__):
pass
else:
self.__dict__[key] = value
def __delattr__(self, key):
if (key == 'track_number'):
setattr(self, key, 0)
elif (key in self.ATTRIBUTES):
setattr(self, key, u"")
def __getattr__(self, key):
if (key in self.ATTRIBUTES):
return self[self.ATTRIBUTES.index(key)]
elif (key in MetaData.__INTEGER_FIELDS__):
return 0
elif (key in MetaData.__FIELDS__):
return u""
else:
raise AttributeError(key)
@classmethod
def converted(cls, metadata):
"""Converts a MetaData object to an ID3v1Comment object."""
if ((metadata is None) or (isinstance(metadata, ID3v1Comment))):
return metadata
return ID3v1Comment(
(metadata.track_name, metadata.artist_name, metadata.album_name,
metadata.year, metadata.comment, int(metadata.track_number)))
def __comment_name__(self):
return u'ID3v1'
def __comment_pairs__(self):
return zip(('Title', 'Artist', 'Album', 'Year', 'Comment', 'Tracknum'),
self)
def build_tag(self):
"""Returns a binary string of this tag's data."""
return self.build_id3v1(self.track_name, self.artist_name,
self.album_name, self.year, self.comment,
self.track_number)
def images(self):
"""Returns an empty list of Image objects."""
return []
def Atom(name):
"""A basic QuickTime atom struct."""
return AtomAdapter(
Con.Struct(name, Con.UBInt32("size"), Con.String("type", 4),
Con.String("data", lambda ctx: ctx["size"] - 8)))
def __init__(self, atom_name, sub_atom):
Con.Struct.__init__(self, atom_name)
self.atom_name = atom_name
self.sub_atom = sub_atom
self.header = Con.Struct(atom_name, Con.UBInt32("size"),
Con.Const(Con.String("type", 4), atom_name))
def _parse(self, stream, context):
header = self.header.parse_stream(stream)
return self.sub_atom.parse_stream(stream)
def _build(self, obj, stream, context):
data = self.sub_atom.build(obj)
stream.write(
self.header.build(
Con.Container(type=self.atom_name, size=len(data) + 8)))
stream.write(data)
def _sizeof(self, context):
return self.sub_atom.sizeof(context) + 8
ATOM_FTYP = Con.Struct("ftyp", Con.String("major_brand", 4),
Con.UBInt32("major_brand_version"),
Con.GreedyRepeater(Con.String("compatible_brands", 4)))
ATOM_MVHD = Con.Struct(
"mvhd", Con.Byte("version"), Con.String("flags", 3),
VersionLength("created_mac_UTC_date"),
VersionLength("modified_mac_UTC_date"), Con.UBInt32("time_scale"),
VersionLength("duration"), Con.UBInt32("playback_speed"),
Con.UBInt16("user_volume"), Con.Padding(10),
Con.Struct("windows", Con.UBInt32("geometry_matrix_a"),
Con.UBInt32("geometry_matrix_b"),
Con.UBInt32("geometry_matrix_u"),
Con.UBInt32("geometry_matrix_c"),
Con.UBInt32("geometry_matrix_d"),
Con.UBInt32("geometry_matrix_v"),
class __TIFF__(ImageMetrics):
HEADER = Con.Struct('header',
Con.String('byte_order', 2),
Con.Switch('order',
lambda ctx: ctx['byte_order'],
{"II": Con.Embed(
Con.Struct('little_endian',
Con.Const(Con.ULInt16('version'), 42),
Con.ULInt32('offset'))),
"MM": Con.Embed(
Con.Struct('big_endian',
Con.Const(Con.UBInt16('version'), 42),
Con.UBInt32('offset')))}))
L_IFD = Con.Struct('ifd',
Con.PrefixedArray(
length_field=Con.ULInt16('length'),
subcon=Con.Struct('tags',
Con.ULInt16('id'),
Con.ULInt16('type'),
Con.ULInt32('count'),
Con.ULInt32('offset'))),
Con.ULInt32('next'))
B_IFD = Con.Struct('ifd',
Con.PrefixedArray(
length_field=Con.UBInt16('length'),
subcon=Con.Struct('tags',
Con.UBInt16('id'),
Con.UBInt16('type'),
Con.UBInt32('count'),
Con.UBInt32('offset'))),
Con.UBInt32('next'))
def __init__(self, width, height, bits_per_pixel, color_count):
ImageMetrics.__init__(self, width, height,
bits_per_pixel, color_count,
u'image/tiff')
@classmethod
def b_tag_value(cls, file, tag):
subtype = {1: Con.Byte("data"),
2: Con.CString("data"),
3: Con.UBInt16("data"),
4: Con.UBInt32("data"),
5: Con.Struct("data",
Con.UBInt32("high"),
Con.UBInt32("low"))}[tag.type]
data = Con.StrictRepeater(tag.count,
subtype)
if ((tag.type != 2) and (data.sizeof() <= 4)):
return tag.offset
else:
file.seek(tag.offset, 0)
return data.parse_stream(file)
@classmethod
def l_tag_value(cls, file, tag):
subtype = {1: Con.Byte("data"),
2: Con.CString("data"),
3: Con.ULInt16("data"),
4: Con.ULInt32("data"),
5: Con.Struct("data",
Con.ULInt32("high"),
Con.ULInt32("low"))}[tag.type]
data = Con.StrictRepeater(tag.count,
subtype)
if ((tag.type != 2) and (data.sizeof() <= 4)):
return tag.offset
else:
file.seek(tag.offset, 0)
return data.parse_stream(file)
@classmethod
def parse(cls, file):
width = 0
height = 0
bits_per_sample = 0
color_count = 0
try:
header = cls.HEADER.parse_stream(file)
if (header.byte_order == 'II'):
IFD = cls.L_IFD
tag_value = cls.l_tag_value
elif (header.byte_order == 'MM'):
IFD = cls.B_IFD
tag_value = cls.b_tag_value
else:
raise InvalidTIFF(_(u'Invalid byte order'))
file.seek(header.offset, 0)
ifd = IFD.parse_stream(file)
while (True):
for tag in ifd.tags:
if (tag.id == 0x0100):
width = tag_value(file, tag)
elif (tag.id == 0x0101):
height = tag_value(file, tag)
elif (tag.id == 0x0102):
try:
bits_per_sample = sum(tag_value(file, tag))
except TypeError:
bits_per_sample = tag_value(file, tag)
elif (tag.id == 0x0140):
color_count = tag.count / 3
else:
pass
if (ifd.next == 0x00):
break
else:
file.seek(ifd.next, 0)
ifd = IFD.parse_stream(file)
return __TIFF__(width, height, bits_per_sample, color_count)
except Con.ConstError:
raise InvalidTIFF(_(u'Invalid TIFF'))
class __PNG__(ImageMetrics):
HEADER = Con.Const(Con.String('header', 8),
'89504e470d0a1a0a'.decode('hex'))
CHUNK_HEADER = Con.Struct('chunk',
Con.UBInt32('length'),
Con.String('type', 4))
CHUNK_FOOTER = Con.Struct('crc32',
Con.UBInt32('crc'))
IHDR = Con.Struct('IHDR',
Con.UBInt32('width'),
Con.UBInt32('height'),
Con.Byte('bit_depth'),
Con.Byte('color_type'),
Con.Byte('compression_method'),
Con.Byte('filter_method'),
Con.Byte('interlace_method'))
def __init__(self, width, height, bits_per_pixel, color_count):
ImageMetrics.__init__(self, width, height, bits_per_pixel, color_count,
u'image/png')
@classmethod
def parse(cls, file):
ihdr = None
plte = None
try:
header = cls.HEADER.parse_stream(file)
chunk_header = cls.CHUNK_HEADER.parse_stream(file)
data = file.read(chunk_header.length)
chunk_footer = cls.CHUNK_FOOTER.parse_stream(file)
while (chunk_header.type != 'IEND'):
if (chunk_header.type == 'IHDR'):
ihdr = cls.IHDR.parse(data)
elif (chunk_header.type == 'PLTE'):
plte = data
chunk_header = cls.CHUNK_HEADER.parse_stream(file)
data = file.read(chunk_header.length)
chunk_footer = cls.CHUNK_FOOTER.parse_stream(file)
if (ihdr.color_type == 0): # grayscale
bits_per_pixel = ihdr.bit_depth
color_count = 0
elif (ihdr.color_type == 2): # RGB
bits_per_pixel = ihdr.bit_depth * 3
color_count = 0
elif (ihdr.color_type == 3): # palette
bits_per_pixel = 8
if ((len(plte) % 3) != 0):
raise InvalidPNG(_(u'Invalid PLTE chunk length'))
else:
color_count = len(plte) / 3
elif (ihdr.color_type == 4): # grayscale + alpha
bits_per_pixel = ihdr.bit_depth * 2
color_count = 0
elif (ihdr.color_type == 6): # RGB + alpha
bits_per_pixel = ihdr.bit_depth * 4
color_count = 0
return __PNG__(ihdr.width, ihdr.height, bits_per_pixel,
color_count)
except Con.ConstError:
raise InvalidPNG(_(u'Invalid PNG'))
class __JPEG__(ImageMetrics):
SEGMENT_HEADER = Con.Struct('segment_header',
Con.Const(Con.Byte('header'), 0xFF),
Con.Byte('type'),
Con.If(
lambda ctx: ctx['type'] not in (0xD8, 0xD9),
Con.UBInt16('length')))
APP0 = Con.Struct('JFIF_segment_marker',
Con.String('identifier', 5),
Con.Byte('major_version'),
Con.Byte('minor_version'),
Con.Byte('density_units'),
Con.UBInt16('x_density'),
Con.UBInt16('y_density'),
Con.Byte('thumbnail_width'),
Con.Byte('thumbnail_height'))
SOF = Con.Struct('start_of_frame',
Con.Byte('data_precision'),
Con.UBInt16('image_height'),
Con.UBInt16('image_width'),
Con.Byte('components'))
def __init__(self, width, height, bits_per_pixel):
ImageMetrics.__init__(self, width, height, bits_per_pixel,
0, u'image/jpeg')
@classmethod
def parse(cls, file):
try:
header = cls.SEGMENT_HEADER.parse_stream(file)
if (header.type != 0xD8):
raise InvalidJPEG(_(u'Invalid JPEG header'))
segment = cls.SEGMENT_HEADER.parse_stream(file)
while (segment.type != 0xD9):
if (segment.type == 0xDA):
break
if (segment.type in (0xC0, 0xC1, 0xC2, 0xC3,
0xC5, 0XC5, 0xC6, 0xC7,
0xC9, 0xCA, 0xCB, 0xCD,
0xCE, 0xCF)): # start of frame
segment_data = cStringIO.StringIO(
file.read(segment.length - 2))
frame0 = cls.SOF.parse_stream(segment_data)
segment_data.close()
return __JPEG__(width=frame0.image_width,
height=frame0.image_height,
bits_per_pixel=(frame0.data_precision *
frame0.components))
else:
file.seek(segment.length - 2, 1)
segment = cls.SEGMENT_HEADER.parse_stream(file)
raise InvalidJPEG(_(u'Start of frame not found'))
except Con.ConstError:
raise InvalidJPEG(_(u"Invalid JPEG segment marker at 0x%X") % \
(file.tell()))
class OggStreamReader:
"""A class for walking through an Ogg stream."""
OGGS = Con.Struct(
"oggs", Con.Const(Con.String("magic_number", 4), "OggS"),
Con.Byte("version"), Con.Byte("header_type"),
Con.SLInt64("granule_position"),
Con.ULInt32("bitstream_serial_number"),
Con.ULInt32("page_sequence_number"), Con.ULInt32("checksum"),
Con.Byte("segments"),
Con.MetaRepeater(lambda ctx: ctx["segments"],
Con.Byte("segment_lengths")))
def __init__(self, stream):
"""stream is a file-like object with read() and close() methods."""
self.stream = stream
def close(self):
"""Closes the sub-stream."""
self.stream.close()
def packets(self, from_beginning=True):
"""Yields one fully reassembled Ogg packet per pass.
Packets are returned as binary strings."""
if (from_beginning):
self.stream.seek(0, 0)
segment = cStringIO.StringIO()
while (True):
try:
page = OggStreamReader.OGGS.parse_stream(self.stream)
for length in page.segment_lengths:
if (length == 255):
segment.write(self.stream.read(length))
else:
segment.write(self.stream.read(length))
yield segment.getvalue()
segment = cStringIO.StringIO()
except Con.core.FieldError:
break
except Con.ConstError:
break
def pages(self, from_beginning=True):
"""Yields a (Container,string) tuple per pass.
Container is parsed from OggStreamReader.OGGS.
string is a binary string of combined segments
(which may not be a complete packet)."""
if (from_beginning):
self.stream.seek(0, 0)
while (True):
try:
page = OggStreamReader.OGGS.parse_stream(self.stream)
yield (page, self.stream.read(sum(page.segment_lengths)))
except Con.core.FieldError:
break
except Con.ConstError:
break
@classmethod
def pages_to_packet(cls, pages_iter):
"""Returns a complete packet as a list of (Container,string) tuples.
pages_iter should be an iterator of (Container,string) tuples
as returned from the pages() method.
"""
packet = [pages_iter.next()]
while (packet[-1][0].segment_lengths[-1] == 255):
packet.append(pages_iter.next())
return packet
CRC_LOOKUP = (
0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7,
0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3,
0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef,
0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb,
0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4,
0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08,
0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc,
0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050,
0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1,
0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5,
0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9,
0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd,
0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2,
0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e,
0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a,
0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676,
0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4)
@classmethod
def calculate_ogg_checksum(cls, page_header, page_data):
"""Calculates an Ogg checksum integer.
page_header is a Container object parsed through OGGS.
page_data is a string of data contained by the page.
"""
old_checksum = page_header.checksum
try:
page_header.checksum = 0
sum = 0
for c in cls.OGGS.build(page_header) + page_data:
sum = ((sum << 8) ^ \
cls.CRC_LOOKUP[((sum >> 24) & 0xFF) ^ ord(c)]) \
& 0xFFFFFFFF
return sum
finally:
page_header.checksum = old_checksum
class WavPackAudio(ApeTaggedAudio, AudioFile):
"""A WavPack audio file."""
SUFFIX = "wv"
NAME = SUFFIX
DEFAULT_COMPRESSION = "standard"
COMPRESSION_MODES = ("veryfast", "fast", "standard", "high", "veryhigh")
APE_TAG_CLASS = WavPackAPEv2
HEADER = Con.Struct(
"wavpackheader", Con.Const(Con.String("id", 4), 'wvpk'),
Con.ULInt32("block_size"), Con.ULInt16("version"),
Con.ULInt8("track_number"), Con.ULInt8("index_number"),
Con.ULInt32("total_samples"), Con.ULInt32("block_index"),
Con.ULInt32("block_samples"),
Con.Embed(
Con.BitStruct("flags", Con.Flag("floating_point_data"),
Con.Flag("hybrid_noise_shaping"),
Con.Flag("cross_channel_decorrelation"),
Con.Flag("joint_stereo"), Con.Flag("hybrid_mode"),
Con.Flag("mono_output"),
Con.Bits("bits_per_sample", 2),
Con.Bits("left_shift_data_low", 3),
Con.Flag("final_block_in_sequence"),
Con.Flag("initial_block_in_sequence"),
Con.Flag("hybrid_noise_balanced"),
Con.Flag("hybrid_mode_control_bitrate"),
Con.Flag("extended_size_integers"),
Con.Bit("sampling_rate_low"),
Con.Bits("maximum_magnitude", 5),
Con.Bits("left_shift_data_high", 2),
Con.Flag("reserved2"), Con.Flag("false_stereo"),
Con.Flag("use_IIR"), Con.Bits("reserved1", 2),
Con.Bits("sampling_rate_high", 3))),
Con.ULInt32("crc"))
SUB_HEADER = Con.Struct(
"wavpacksubheader",
Con.Embed(
Con.BitStruct("flags", Con.Flag("large_block"),
Con.Flag("actual_size_1_less"),
Con.Flag("nondecoder_data"),
Con.Bits("metadata_function", 5))),
Con.IfThenElse('size', lambda ctx: ctx['large_block'], ULInt24('s'),
Con.Byte('s')))
BITS_PER_SAMPLE = (8, 16, 24, 32)
SAMPLING_RATE = (6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,
32000, 44100, 48000, 64000, 88200, 96000, 192000, 0)
__options__ = {
"veryfast": {
"block_size": 44100,
"joint_stereo": True,
"false_stereo": True,
"wasted_bits": True,
"decorrelation_passes": 1
},
"fast": {
"block_size": 44100,
"joint_stereo": True,
"false_stereo": True,
"wasted_bit": True,
"decorrelation_passes": 2
},
"standard": {
"block_size": 44100,
"joint_stereo": True,
"false_stereo": True,
"wasted_bits": True,
"decorrelation_passes": 5
},
"high": {
"block_size": 44100,
"joint_stereo": True,
"false_stereo": True,
"wasted_bits": True,
"decorrelation_passes": 10
},
"veryhigh": {
"block_size": 44100,
"joint_stereo": True,
"false_stereo": True,
"wasted_bits": True,
"decorrelation_passes": 16
}
}
def __init__(self, filename):
"""filename is a plain string."""
self.filename = filename
self.__samplerate__ = 0
self.__channels__ = 0
self.__bitspersample__ = 0
self.__total_frames__ = 0
try:
self.__read_info__()
except IOError, msg:
raise InvalidWavPack(str(msg))
