def __init__(self, fileobj):
super().__init__(RiffChunk, fileobj)
if self.root.id != u'RIFF':
raise InvalidChunk("Root chunk must be a RIFF chunk, got %s"
% self.root.id)
self.file_type = self.root.name
def __init__(self, fileobj):
# AIFF Files always start with the FORM chunk which contains a 4 byte
# ID before the start of other chunks
super().__init__(AIFFChunk, fileobj)
if self.root.id != u'FORM':
raise InvalidChunk("Root chunk must be a FORM chunk, got %s" %
self.root.id)
def __init__(self, fileobj, id, data_size, parent_chunk):
if id not in (u'RIFF', u'LIST'):
raise InvalidChunk('Expected RIFF or LIST chunk, got %s' % id)
RiffChunk.__init__(self, fileobj, id, data_size, parent_chunk)
self.init_container()
def __init__(self, fileobj):
super().__init__(DSDIFFChunk, fileobj)
if self.root.id != u'FRM8':
raise InvalidChunk("Root chunk must be a FRM8 chunk, got %r" %
self.root)
def __init__(self, fileobj, id, data_size, parent_chunk):
if id != 'DST':
raise InvalidChunk('Not a DST chunk: %s' % id)
DSDIFFChunk.__init__(self, fileobj, id, data_size, parent_chunk)
self.init_container(name_size=0)
def __init__(self, fileobj, id, data_size, parent_chunk):
if id not in self.LIST_CHUNK_IDS:
raise InvalidChunk('Not a list chunk: %s' % id)
DSDIFFChunk.__init__(self, fileobj, id, data_size, parent_chunk)
self.init_container()
def __init__(self, fileobj):
"""Raises error"""
iff = DSDIFFFile(fileobj)
try:
prop_chunk = iff['PROP']
except KeyError as e:
raise error(str(e))
if prop_chunk.name == 'SND ':
for chunk in prop_chunk.subchunks():
if chunk.id == 'FS' and chunk.data_size == 4:
data = chunk.read()
if len(data) < 4:
raise InvalidChunk("Not enough data in FS chunk")
self.sample_rate, = struct.unpack('>L', data[:4])
elif chunk.id == 'CHNL' and chunk.data_size >= 2:
data = chunk.read()
if len(data) < 2:
raise InvalidChunk("Not enough data in CHNL chunk")
self.channels, = struct.unpack('>H', data[:2])
elif chunk.id == 'CMPR' and chunk.data_size >= 4:
data = chunk.read()
if len(data) < 4:
raise InvalidChunk("Not enough data in CMPR chunk")
compression_id, = struct.unpack('>4s', data[:4])
self.compression = compression_id.decode('ascii').rstrip()
if self.sample_rate < 0:
raise error("Invalid sample rate")
if self.compression == 'DSD': # not compressed
try:
dsd_chunk = iff['DSD']
except KeyError as e:
raise error(str(e))
# DSD data has one bit per sample. Eight samples of a channel
# are clustered together for a channel byte. For multiple channels
# the channel bytes are interleaved (in the order specified in the
# CHNL chunk). See DSDIFF spec chapter 3.3.
sample_count = dsd_chunk.data_size * 8 / (self.channels or 1)
if self.sample_rate != 0:
self.length = sample_count / float(self.sample_rate)
self.bitrate = (self.channels * self.bits_per_sample *
self.sample_rate)
elif self.compression == 'DST':
try:
dst_frame = iff['DST']
dst_frame_info = dst_frame['FRTE']
except KeyError as e:
raise error(str(e))
if dst_frame_info.data_size >= 6:
data = dst_frame_info.read()
if len(data) < 6:
raise InvalidChunk("Not enough data in FRTE chunk")
frame_count, frame_rate = struct.unpack('>LH', data[:6])
if frame_rate:
self.length = frame_count / frame_rate
if frame_count:
dst_data_size = dst_frame.data_size - dst_frame_info.size
avg_frame_size = dst_data_size / frame_count
self.bitrate = avg_frame_size * 8 * frame_rate
def __init__(self, fileobj, id, data_size, parent_chunk):
if id != u'FORM':
raise InvalidChunk('Expected FORM chunk, got %s' % id)
AIFFChunk.__init__(self, fileobj, id, data_size, parent_chunk)
self.init_container()