예제 #1
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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'))
예제 #2
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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))
예제 #3
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 def __init__(self, name):
     Con.Adapter.__init__(
         self,
         Con.Struct(
             name,
             Con.Embed(
                 Con.BitStruct(None, Con.Flag("signed"),
                               Con.Bits("exponent", 15))),
             Con.UBInt64("mantissa")))
예제 #4
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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
                       Con.UBInt16("quicktime_audio_packet_size"),
                       Con.String("sample_rate", 4))

#out of all this mess, the only interesting bits are the _bit_rate fields
#and (maybe) the buffer_size
#everything else is a constant of some kind as far as I can tell
ATOM_ESDS = Con.Struct(
    "esds", Con.Byte("version"), Con.String("flags", 3),
    Con.Byte("ES_descriptor_type"),
    Con.StrictRepeater(3, Con.Byte("extended_descriptor_type_tag")),
    Con.Byte("descriptor_type_length"), Con.UBInt16("ES_ID"),
    Con.Byte("stream_priority"), Con.Byte("decoder_config_descriptor_type"),
    Con.StrictRepeater(3, Con.Byte("extended_descriptor_type_tag2")),
    Con.Byte("descriptor_type_length2"), Con.Byte("object_ID"),
    Con.Embed(
        Con.BitStruct(None, Con.Bits("stream_type", 6),
                      Con.Flag("upstream_flag"), Con.Flag("reserved_flag"),
                      Con.Bits("buffer_size", 24))),
    Con.UBInt32("maximum_bit_rate"), Con.UBInt32("average_bit_rate"),
    Con.Byte('decoder_specific_descriptor_type3'),
    Con.StrictRepeater(3, Con.Byte("extended_descriptor_type_tag2")),
    Con.PrefixedArray(length_field=Con.Byte("ES_header_length"),
                      subcon=Con.Byte("ES_header_start_codes")),
    Con.Byte("SL_config_descriptor_type"),
    Con.StrictRepeater(3, Con.Byte("extended_descriptor_type_tag3")),
    Con.Byte("descriptor_type_length3"), Con.Byte("SL_value"))

ATOM_STTS = Con.Struct(
    'stts', Con.Byte("version"), Con.String("flags", 3),
    Con.PrefixedArray(length_field=Con.UBInt32("total_counts"),
                      subcon=Con.Struct("frame_size_counts",
                                        Con.UBInt32("frame_count"),
예제 #6
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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'))
예제 #7
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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))