def __init__(self, fileobj):
header = fileobj.read(76)
if len(header) != 76 or not header.startswith(b"MAC "):
raise MonkeysAudioHeaderError("not a Monkey's Audio file")
self.version = cdata.ushort_le(header[4:6])
if self.version >= 3980:
(
blocks_per_frame,
final_frame_blocks,
total_frames,
self.bits_per_sample,
self.channels,
self.sample_rate,
) = struct.unpack("<IIIHHI", header[56:76])
else:
compression_level = cdata.ushort_le(header[6:8])
self.channels, self.sample_rate = struct.unpack("<HI", header[10:16])
total_frames, final_frame_blocks = struct.unpack("<II", header[24:32])
if self.version >= 3950:
blocks_per_frame = 73728 * 4
elif self.version >= 3900 or (self.version >= 3800 and compression_level == 4):
blocks_per_frame = 73728
else:
blocks_per_frame = 9216
self.version /= 1000.0
self.length = 0.0
if (self.sample_rate != 0) and (total_frames > 0):
total_blocks = (total_frames - 1) * blocks_per_frame + final_frame_blocks
self.length = float(total_blocks) / self.sample_rate
def __init__(self, fileobj):
header = fileobj.read(76)
if len(header) != 76 or not header.startswith(b"MAC "):
raise MonkeysAudioHeaderError("not a Monkey's Audio file")
self.version = cdata.ushort_le(header[4:6])
if self.version >= 3980:
(blocks_per_frame, final_frame_blocks, total_frames,
self.bits_per_sample, self.channels,
self.sample_rate) = struct.unpack("<IIIHHI", header[56:76])
else:
compression_level = cdata.ushort_le(header[6:8])
self.channels, self.sample_rate = struct.unpack(
"<HI", header[10:16])
total_frames, final_frame_blocks = struct.unpack(
"<II", header[24:32])
if self.version >= 3950:
blocks_per_frame = 73728 * 4
elif self.version >= 3900 or (self.version >= 3800
and compression_level == 4):
blocks_per_frame = 73728
else:
blocks_per_frame = 9216
self.version /= 1000.0
self.length = 0.0
if (self.sample_rate != 0) and (total_frames > 0):
total_blocks = ((total_frames - 1) * blocks_per_frame +
final_frame_blocks)
self.length = float(total_blocks) / self.sample_rate
def __parse_sv467(self, fileobj):
fileobj.seek(-4, 1)
header = fileobj.read(32)
if len(header) != 32:
raise MusepackHeaderError("not a Musepack file")
# SV7
if header.startswith(b"MP+"):
self.version = bytearray(header)[3] & 0xF
if self.version < 7:
raise MusepackHeaderError("not a Musepack file")
frames = cdata.uint_le(header[4:8])
flags = cdata.uint_le(header[8:12])
self.title_peak, self.title_gain = struct.unpack(
"<Hh", header[12:16])
self.album_peak, self.album_gain = struct.unpack(
"<Hh", header[16:20])
self.title_gain /= 100.0
self.album_gain /= 100.0
self.title_peak /= 65535.0
self.album_peak /= 65535.0
self.sample_rate = RATES[(flags >> 16) & 0x0003]
self.bitrate = 0
# SV4-SV6
else:
header_dword = cdata.uint_le(header[0:4])
self.version = (header_dword >> 11) & 0x03FF
if self.version < 4 or self.version > 6:
raise MusepackHeaderError("not a Musepack file")
self.bitrate = (header_dword >> 23) & 0x01FF
self.sample_rate = 44100
if self.version >= 5:
frames = cdata.uint_le(header[4:8])
else:
frames = cdata.ushort_le(header[6:8])
if self.version < 6:
frames -= 1
self.channels = 2
self.length = float(frames * 1152 - 576) / self.sample_rate
def __parse_sv467(self, fileobj):
fileobj.seek(-4, 1)
header = fileobj.read(32)
if len(header) != 32:
raise MusepackHeaderError("not a Musepack file")
# SV7
if header.startswith(b"MP+"):
self.version = bytearray(header)[3] & 0xF
if self.version < 7:
raise MusepackHeaderError("not a Musepack file")
frames = cdata.uint_le(header[4:8])
flags = cdata.uint_le(header[8:12])
self.title_peak, self.title_gain = struct.unpack(
"<Hh", header[12:16])
self.album_peak, self.album_gain = struct.unpack(
"<Hh", header[16:20])
self.title_gain /= 100.0
self.album_gain /= 100.0
self.title_peak /= 65535.0
self.album_peak /= 65535.0
self.sample_rate = RATES[(flags >> 16) & 0x0003]
self.bitrate = 0
# SV4-SV6
else:
header_dword = cdata.uint_le(header[0:4])
self.version = (header_dword >> 11) & 0x03FF
if self.version < 4 or self.version > 6:
raise MusepackHeaderError("not a Musepack file")
self.bitrate = (header_dword >> 23) & 0x01FF
self.sample_rate = 44100
if self.version >= 5:
frames = cdata.uint_le(header[4:8])
else:
frames = cdata.ushort_le(header[6:8])
if self.version < 6:
frames -= 1
self.channels = 2
self.length = float(frames * 1152 - 576) / self.sample_rate
def from_fileobj(cls, fileobj):
"""A new _WavPackHeader or raises WavPackHeaderError"""
header = fileobj.read(32)
if len(header) != 32 or not header.startswith(b"wvpk"):
raise WavPackHeaderError("not a WavPack header: %r" % header)
block_size = cdata.uint_le(header[4:8])
version = cdata.ushort_le(header[8:10])
track_no = ord(header[10:11])
index_no = ord(header[11:12])
samples = cdata.uint_le(header[12:16])
if samples == 2 ** 32 - 1:
samples = -1
block_index = cdata.uint_le(header[16:20])
block_samples = cdata.uint_le(header[20:24])
flags = cdata.uint_le(header[24:28])
crc = cdata.uint_le(header[28:32])
return _WavPackHeader(block_size, version, track_no, index_no,
samples, block_index, block_samples, flags, crc)
