aifc.py: added missing tell() method in AIFC write class;
use audioop module as backup for cl module when reading or writing u-law compressed files. sunau.py: interface with the same methods as aifc for Sun and NeXT audio files
This commit is contained in:
Sjoerd Mullender
parent
66bca326cb
commit
43bf0bc857
145
Lib/aifc.py
145
Lib/aifc.py
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@ -40,7 +40,7 @@
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# <size of the samples> (2 bytes)
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# <sampling frequency> (10 bytes, IEEE 80-bit extended
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# floating point)
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# if AIFF-C files only:
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# in AIFF-C files only:
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# <compression type> (4 bytes)
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# <human-readable version of compression type> ("pstring")
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# SSND
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@ -58,9 +58,9 @@
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# or
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# f = aifc.openfp(filep, 'r')
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# where file is the name of a file and filep is an open file pointer.
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# The open file pointer must have methods read(), seek(), and
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# close(). In some types of audio files, if the setpos() method is
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# not used, the seek() method is not necessary.
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# The open file pointer must have methods read(), seek(), and close().
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# In some types of audio files, if the setpos() method is not used,
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# the seek() method is not necessary.
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#
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# This returns an instance of a class with the following public methods:
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# getnchannels() -- returns number of audio channels (1 for
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@ -85,6 +85,8 @@
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# The position returned by tell(), the position given to setpos() and
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# the position of marks are all compatible and have nothing to do with
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# the actual postion in the file.
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# The close() method is called automatically when the class instance
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# is destroyed.
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#
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# Writing AIFF files:
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# f = aifc.open(file, 'w')
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@ -122,11 +124,13 @@
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# but when it is set to the correct value, the header does not have to
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# be patched up.
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# It is best to first set all parameters, perhaps possibly the
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# compression type, and the write audio frames using writeframesraw.
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# compression type, and then write audio frames using writeframesraw.
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# When all frames have been written, either call writeframes('') or
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# close() to patch up the sizes in the header.
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# Marks can be added anytime. If there are any marks, ypu must call
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# close() after all frames have been written.
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# The close() method is called automatically when the class instance
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# is destroyed.
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#
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# When a file is opened with the extension '.aiff', an AIFF file is
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# written, otherwise an AIFF-C file is written. This default can be
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@ -347,7 +351,7 @@ class Aifc_read:
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# methods
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# _soundpos -- the position in the audio stream
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# available through the tell() method, set through the
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# tell() method
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# setpos() method
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#
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# These variables are used internally only:
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# _version -- the AIFF-C version number
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@ -362,6 +366,7 @@ class Aifc_read:
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self._file = file
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self._version = 0
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self._decomp = None
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self._convert = None
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self._markers = []
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self._soundpos = 0
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form = self._file.read(4)
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@ -433,6 +438,10 @@ class Aifc_read:
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def init(self, filename):
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return self.initfp(builtin.open(filename, 'r'))
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def __del__(self):
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if self._file:
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self.close()
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#
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# User visible methods.
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#
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@ -475,8 +484,9 @@ class Aifc_read:
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## return self._version
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def getparams(self):
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return self._nchannels, self._sampwidth, self._framerate, \
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self._nframes, self._comptype, self._compname
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return self.getnchannels(), self.getsampwidth(), \
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self.getframerate(), self.getnframes(), \
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self.getcomptype(), self.getcompname()
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def getmarkers(self):
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if len(self._markers) == 0:
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@ -506,16 +516,24 @@ class Aifc_read:
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if nframes == 0:
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return ''
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data = self._ssnd_chunk.read(nframes * self._framesize)
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if self._decomp and data:
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dummy = self._decomp.SetParam(CL.FRAME_BUFFER_SIZE, \
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len(data) * 2)
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data = self._decomp.Decompress(len(data) / self._nchannels, data)
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if self._convert and data:
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data = self._convert(data)
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self._soundpos = self._soundpos + len(data) / (self._nchannels * self._sampwidth)
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return data
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#
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# Internal methods.
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#
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def _decomp_data(self, data):
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dummy = self._decomp.SetParam(CL.FRAME_BUFFER_SIZE,
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len(data) * 2)
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return self._decomp.Decompress(len(data) / self._nchannels,
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data)
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def _ulaw2lin(self, data):
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import audioop
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return audioop.ulaw2lin(data, 2)
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def _read_comm_chunk(self, chunk):
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nchannels = _read_short(chunk)
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self._nchannels = _convert1(nchannels, _nchannelslist)
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@ -547,6 +565,14 @@ class Aifc_read:
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try:
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import cl, CL
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except ImportError:
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if self._comptype == 'ULAW':
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try:
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import audioop
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self._convert = self._ulaw2lin
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self._framesize = self._framesize / 2
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return
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except ImportError:
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pass
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raise Error, 'cannot read compressed AIFF-C files'
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if self._comptype == 'ULAW':
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scheme = CL.G711_ULAW
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@ -557,6 +583,7 @@ class Aifc_read:
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else:
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raise Error, 'unsupported compression type'
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self._decomp = cl.OpenDecompressor(scheme)
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self._convert = self._decomp_data
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else:
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self._comptype = 'NONE'
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self._compname = 'not compressed'
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@ -622,6 +649,7 @@ class Aifc_write:
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self._comptype = 'NONE'
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self._compname = 'not compressed'
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self._comp = None
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self._convert = None
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self._nchannels = 0
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self._sampwidth = 0
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self._framerate = 0
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@ -634,6 +662,10 @@ class Aifc_write:
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self._aifc = 1 # AIFF-C is default
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return self
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def __del__(self):
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if self._file:
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self.close()
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#
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# User visible methods.
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#
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@ -752,15 +784,14 @@ class Aifc_write:
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return None
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return self._markers
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def tell(self):
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return self._nframeswritten
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def writeframesraw(self, data):
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self._ensure_header_written(len(data))
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nframes = len(data) / (self._sampwidth * self._nchannels)
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if self._comp:
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dummy = self._comp.SetParam(CL.FRAME_BUFFER_SIZE, \
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len(data))
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dummy = self._comp.SetParam(CL.COMPRESSED_BUFFER_SIZE,\
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len(data))
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data = self._comp.Compress(nframes, data)
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if self._convert:
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data = self._convert(data)
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self._file.write(data)
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self._nframeswritten = self._nframeswritten + nframes
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self._datawritten = self._datawritten + len(data)
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@ -791,6 +822,15 @@ class Aifc_write:
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#
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# Internal methods.
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#
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def _comp_data(self, data):
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dum = self._comp.SetParam(CL.FRAME_BUFFER_SIZE, len(data))
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dum = self._comp.SetParam(CL.COMPRESSED_BUFFER_SIZE, len(data))
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return self._comp.Compress(nframes, data)
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def _lin2ulaw(self, data):
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import audioop
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return audioop.lin2ulaw(data, 2)
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def _ensure_header_written(self, datasize):
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if not self._nframeswritten:
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if self._comptype in ('ULAW', 'ALAW'):
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@ -806,37 +846,48 @@ class Aifc_write:
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raise Error, 'sampling rate not specified'
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self._write_header(datasize)
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def _init_compression(self):
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try:
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import cl, CL
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except ImportError:
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if self._comptype == 'ULAW':
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try:
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import audioop
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self._convert = self._lin2ulaw
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return
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except ImportError:
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pass
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raise Error, 'cannot write compressed AIFF-C files'
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if self._comptype == 'ULAW':
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scheme = CL.G711_ULAW
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elif self._comptype == 'ALAW':
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scheme = CL.G711_ALAW
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else:
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raise Error, 'unsupported compression type'
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self._comp = cl.OpenCompressor(scheme)
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params = [CL.ORIGINAL_FORMAT, 0, \
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CL.BITS_PER_COMPONENT, 0, \
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CL.FRAME_RATE, self._framerate, \
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CL.FRAME_BUFFER_SIZE, 100, \
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CL.COMPRESSED_BUFFER_SIZE, 100]
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if self._nchannels == AL.MONO:
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params[1] = CL.MONO
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else:
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params[1] = CL.STEREO_INTERLEAVED
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if self._sampwidth == AL.SAMPLE_8:
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params[3] = 8
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elif self._sampwidth == AL.SAMPLE_16:
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params[3] = 16
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else:
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params[3] = 24
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self._comp.SetParams(params)
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# the compressor produces a header which we ignore
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dummy = self._comp.Compress(0, '')
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self._convert = self._comp_data
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def _write_header(self, initlength):
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if self._aifc and self._comptype != 'NONE':
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try:
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import cl, CL
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except ImportError:
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raise Error, 'cannot write compressed AIFF-C files'
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if self._comptype == 'ULAW':
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scheme = CL.G711_ULAW
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elif self._comptype == 'ALAW':
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scheme = CL.G711_ALAW
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else:
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raise Error, 'unsupported compression type'
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self._comp = cl.OpenCompressor(scheme)
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params = [CL.ORIGINAL_FORMAT, 0, \
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CL.BITS_PER_COMPONENT, 0, \
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CL.FRAME_RATE, self._framerate, \
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CL.FRAME_BUFFER_SIZE, 100, \
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CL.COMPRESSED_BUFFER_SIZE, 100]
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if self._nchannels == AL.MONO:
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params[1] = CL.MONO
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else:
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params[1] = CL.STEREO_INTERLEAVED
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if self._sampwidth == AL.SAMPLE_8:
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params[3] = 8
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elif self._sampwidth == AL.SAMPLE_16:
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params[3] = 16
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else:
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params[3] = 24
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self._comp.SetParams(params)
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# the compressor produces a header which we ignore
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dummy = self._comp.Compress(0, '')
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self._init_compression()
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self._file.write('FORM')
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if not self._nframes:
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self._nframes = initlength / (self._nchannels * self._sampwidth)
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@ -0,0 +1,471 @@
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# Stuff to parse Sun and NeXT audio files.
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#
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# An audio consists of a header followed by the data. The structure
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# of the header is as follows.
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#
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# +---------------+
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# | magic word |
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# +---------------+
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# | header size |
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# +---------------+
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# | data size |
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# +---------------+
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# | encoding |
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# +---------------+
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# | sample rate |
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# +---------------+
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# | # of channels |
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# +---------------+
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# | info |
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# | |
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# +---------------+
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#
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# The magic word consists of the 4 characters '.snd'. Apart from the
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# info field, all header fields are 4 bytes in size. They are all
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# 32-bit unsigned integers encoded in big-endian byte order.
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#
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# The header size really gives the start of the data.
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# The data size is the physical size of the data. From the other
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# parameter the number of frames can be calculated.
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# The encoding gives the way in which audio samples are encoded.
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# Possible values are listed below.
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# The info field currently consists of an ASCII string giving a
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# human-readable description of the audio file. The info field is
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# padded with NUL bytes to the header size.
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#
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# Usage.
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#
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# Reading audio files:
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# f = au.open(file, 'r')
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# or
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# f = au.openfp(filep, 'r')
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# where file is the name of a file and filep is an open file pointer.
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# The open file pointer must have methods read(), seek(), and close().
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# When the setpos() and rewind() methods are not used, the seek()
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# method is not necessary.
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#
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# This returns an instance of a class with the following public methods:
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# getnchannels() -- returns number of audio channels (1 for
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# mono, 2 for stereo)
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# getsampwidth() -- returns sample width in bytes
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# getframerate() -- returns sampling frequency
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# getnframes() -- returns number of audio frames
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# getcomptype() -- returns compression type ('NONE' for AIFF files)
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# getcompname() -- returns human-readable version of
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# compression type ('not compressed' for AIFF files)
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# getparams() -- returns a tuple consisting of all of the
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# above in the above order
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# getmarkers() -- returns None (for compatibility with the
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# aifc module)
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# getmark(id) -- raises an error since the mark does not
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# exist (for compatibility with the aifc module)
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# readframes(n) -- returns at most n frames of audio
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# rewind() -- rewind to the beginning of the audio stream
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# setpos(pos) -- seek to the specified position
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# tell() -- return the current position
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# close() -- close the instance (make it unusable)
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# The position returned by tell() and the position given to setpos()
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# are compatible and have nothing to do with the actual postion in the
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# file.
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# The close() method is called automatically when the class instance
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# is destroyed.
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#
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# Writing audio files:
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# f = au.open(file, 'w')
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# or
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# f = au.openfp(filep, 'w')
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# where file is the name of a file and filep is an open file pointer.
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# The open file pointer must have methods write(), tell(), seek(), and
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# close().
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#
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# This returns an instance of a class with the following public methods:
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# setnchannels(n) -- set the number of channels
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# setsampwidth(n) -- set the sample width
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# setframerate(n) -- set the frame rate
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# setnframes(n) -- set the number of frames
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# setcomptype(type, name)
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# -- set the compression type and the
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# human-readable compression type
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# setparams(nchannels, sampwidth, framerate, nframes, comptype, compname)
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# -- set all parameters at once
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# tell() -- return current position in output file
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# writeframesraw(data)
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# -- write audio frames without pathing up the
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# file header
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# writeframes(data)
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# -- write audio frames and patch up the file header
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# close() -- patch up the file header and close the
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# output file
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# You should set the parameters before the first writeframesraw or
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# writeframes. The total number of frames does not need to be set,
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# but when it is set to the correct value, the header does not have to
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# be patched up.
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# It is best to first set all parameters, perhaps possibly the
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# compression type, and then write audio frames using writeframesraw.
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# When all frames have been written, either call writeframes('') or
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# close() to patch up the sizes in the header.
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# The close() method is called automatically when the class instance
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# is destroyed.
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# from <multimedia/audio_filehdr.h>
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AUDIO_FILE_MAGIC = 0x2e736e64
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AUDIO_FILE_ENCODING_MULAW_8 = 1
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AUDIO_FILE_ENCODING_LINEAR_8 = 2
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AUDIO_FILE_ENCODING_LINEAR_16 = 3
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AUDIO_FILE_ENCODING_LINEAR_24 = 4
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AUDIO_FILE_ENCODING_LINEAR_32 = 5
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AUDIO_FILE_ENCODING_FLOAT = 6
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AUDIO_FILE_ENCODING_DOUBLE = 7
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AUDIO_FILE_ENCODING_ADPCM_G721 = 23
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AUDIO_FILE_ENCODING_ADPCM_G722 = 24
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AUDIO_FILE_ENCODING_ADPCM_G723_3 = 25
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AUDIO_FILE_ENCODING_ADPCM_G723_5 = 26
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AUDIO_FILE_ENCODING_ALAW_8 = 27
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# from <multimedia/audio_hdr.h>
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AUDIO_UNKNOWN_SIZE = 0xFFFFFFFFL # ((unsigned)(~0))
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_simple_encodings = [AUDIO_FILE_ENCODING_MULAW_8,
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AUDIO_FILE_ENCODING_LINEAR_8,
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AUDIO_FILE_ENCODING_LINEAR_16,
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AUDIO_FILE_ENCODING_LINEAR_24,
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AUDIO_FILE_ENCODING_LINEAR_32,
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AUDIO_FILE_ENCODING_ALAW_8]
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def _read_u32(file):
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x = 0L
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for i in range(4):
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byte = file.read(1)
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if byte == '':
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raise EOFError
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x = x*256 + ord(byte)
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return x
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def _write_u32(file, x):
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data = []
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for i in range(4):
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d, m = divmod(x, 256)
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data.insert(0, m)
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x = d
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for i in range(4):
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file.write(chr(int(data[i])))
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class Au_read:
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def initfp(self, file):
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self._file = file
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self._soundpos = 0
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magic = int(_read_u32(file))
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if magic != AUDIO_FILE_MAGIC:
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raise Error, 'bad magic number'
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self._hdr_size = int(_read_u32(file))
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if self._hdr_size < 24:
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raise Error, 'header size too small'
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if self._hdr_size > 100:
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raise Error, 'header size rediculously large'
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self._data_size = _read_u32(file)
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if self._data_size != AUDIO_UNKNOWN_SIZE:
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self._data_size = int(self._data_size)
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self._encoding = int(_read_u32(file))
|
||||
if self._encoding not in _simple_encodings:
|
||||
raise Error, 'encoding not (yet) supported'
|
||||
if self._encoding in (AUDIO_FILE_ENCODING_MULAW_8,
|
||||
AUDIO_FILE_ENCODING_LINEAR_8,
|
||||
AUDIO_FILE_ENCODING_ALAW_8):
|
||||
self._sampwidth = 2
|
||||
self._framesize = 1
|
||||
elif self._encoding == AUDIO_FILE_ENCODING_LINEAR_16:
|
||||
self._framesize = self._sampwidth = 2
|
||||
elif self._encoding == AUDIO_FILE_ENCODING_LINEAR_24:
|
||||
self._framesize = self._sampwidth = 3
|
||||
elif self._encoding == AUDIO_FILE_ENCODING_LINEAR_32:
|
||||
self._framesize = self._sampwidth = 4
|
||||
else:
|
||||
raise Error, 'unknown encoding'
|
||||
self._framerate = int(_read_u32(file))
|
||||
self._nchannels = int(_read_u32(file))
|
||||
self._framesize = self._framesize * self._nchannels
|
||||
if self._hdr_size > 24:
|
||||
self._info = file.read(self._hdr_size - 24)
|
||||
for i in range(len(self._info)):
|
||||
if self._info[i] == '\0':
|
||||
self._info = self._info[:i]
|
||||
break
|
||||
else:
|
||||
self._info = ''
|
||||
return self
|
||||
|
||||
def init(self, filename):
|
||||
import builtin
|
||||
return self.initfp(builtin.open(filename, 'r'))
|
||||
|
||||
def __del__(self):
|
||||
if self._file:
|
||||
self.close()
|
||||
|
||||
def getfp(self):
|
||||
return self._file
|
||||
|
||||
def getnchannels(self):
|
||||
return self._nchannels
|
||||
|
||||
def getsampwidth(self):
|
||||
return self._sampwidth
|
||||
|
||||
def getframerate(self):
|
||||
return self._framerate
|
||||
|
||||
def getnframes(self):
|
||||
if self._data_size == AUDIO_UNKNOWN_SIZE:
|
||||
return AUDIO_UNKNOWN_SIZE
|
||||
if self._encoding in _simple_encodings:
|
||||
return self._data_size / self._framesize
|
||||
return 0 # XXX--must do some arithmetic here
|
||||
|
||||
def getcomptype(self):
|
||||
if self._encoding == AUDIO_FILE_ENCODING_MULAW_8:
|
||||
return 'ULAW'
|
||||
elif self._encoding == AUDIO_FILE_ENCODING_ALAW_8:
|
||||
return 'ALAW'
|
||||
else:
|
||||
return 'NONE'
|
||||
|
||||
def getcompname(self):
|
||||
if self._encoding == AUDIO_FILE_ENCODING_MULAW_8:
|
||||
return 'CCITT G.711 u-law'
|
||||
elif self._encoding == AUDIO_FILE_ENCODING_ALAW_8:
|
||||
return 'CCITT G.711 A-law'
|
||||
else:
|
||||
return 'not compressed'
|
||||
|
||||
def getparams(self):
|
||||
return self.getnchannels(), self.getsampwidth(), \
|
||||
self.getframerate(), self.getnframes(), \
|
||||
self.getcomptype(), self.getcompname()
|
||||
|
||||
def getmarkers(self):
|
||||
return None
|
||||
|
||||
def getmark(self, id):
|
||||
raise Error, 'no marks'
|
||||
|
||||
def readframes(self, nframes):
|
||||
if self._encoding in _simple_encodings:
|
||||
if nframes == AUDIO_UNKNOWN_SIZE:
|
||||
data = self._file.read()
|
||||
else:
|
||||
data = self._file.read(nframes * self._sampwidth * self._nchannels)
|
||||
if self._encoding == AUDIO_FILE_ENCODING_MULAW_8:
|
||||
import audioop
|
||||
data = audioop.ulaw2lin(data, self._sampwidth)
|
||||
return data
|
||||
return None # XXX--not implemented yet
|
||||
|
||||
def rewind(self):
|
||||
self._soundpos = 0
|
||||
self._file.seek(self._hdr_size)
|
||||
|
||||
def tell(self):
|
||||
return self._soundpos
|
||||
|
||||
def setpos(self, pos):
|
||||
if pos < 0 or pos > self.getnframes():
|
||||
raise Error, 'position not in range'
|
||||
self._file.seek(pos * self._framesize + self._hdr_size)
|
||||
self._soundpos = pos
|
||||
|
||||
def close(self):
|
||||
self._file.close()
|
||||
self._file = None
|
||||
|
||||
class Au_write:
|
||||
def init(self, filename):
|
||||
import builtin
|
||||
return self.initfp(builtin.open(filename, 'w'))
|
||||
|
||||
def initfp(self, file):
|
||||
self._file = file
|
||||
self._framerate = 0
|
||||
self._nchannels = 0
|
||||
self._sampwidth = 0
|
||||
self._framesize = 0
|
||||
self._nframes = AUDIO_UNKNOWN_SIZE
|
||||
self._nframeswritten = 0
|
||||
self._datawritten = 0
|
||||
self._datalength = 0
|
||||
self._info = ''
|
||||
self._comptype = 'ULAW' # default is U-law
|
||||
return self
|
||||
|
||||
def __del__(self):
|
||||
if self._file:
|
||||
self.close()
|
||||
|
||||
def setnchannels(self, nchannels):
|
||||
if self._nframeswritten:
|
||||
raise Error, 'cannot change parameters after starting to write'
|
||||
if nchannels not in (1, 2, 4):
|
||||
raise Error, 'only 1, 2, or 4 channels supported'
|
||||
self._nchannels = nchannels
|
||||
|
||||
def getnchannels(self):
|
||||
if not self._nchannels:
|
||||
raise Error, 'number of channels not set'
|
||||
return self._nchannels
|
||||
|
||||
def setsampwidth(self, sampwidth):
|
||||
if self._nframeswritten:
|
||||
raise Error, 'cannot change parameters after starting to write'
|
||||
if sampwidth not in (1, 2, 4):
|
||||
raise Error, 'bad sample width'
|
||||
self._sampwidth = sampwidth
|
||||
|
||||
def getsampwidth(self):
|
||||
if not self._framerate:
|
||||
raise Error, 'sample width not specified'
|
||||
return self._sampwidth
|
||||
|
||||
def setframerate(self, framerate):
|
||||
if self._nframeswritten:
|
||||
raise Error, 'cannot change parameters after starting to write'
|
||||
self._framerate = framerate
|
||||
|
||||
def getframerate(self):
|
||||
if not self._framerate:
|
||||
raise Error, 'frame rate not set'
|
||||
return self._framerate
|
||||
|
||||
def setnframes(self, nframes):
|
||||
if self._nframeswritten:
|
||||
raise Error, 'cannot change parameters after starting to write'
|
||||
if nframes < 0:
|
||||
raise Error, '# of frames cannot be negative'
|
||||
self._nframes = nframes
|
||||
|
||||
def getnframes(self):
|
||||
return self._nframeswritten
|
||||
|
||||
def setcomptype(self, type, name):
|
||||
if type in ('NONE', 'ULAW'):
|
||||
self._comptype = type
|
||||
else:
|
||||
raise Error, 'unknown compression type'
|
||||
|
||||
def getcomptype(self):
|
||||
return self._comptype
|
||||
|
||||
def getcompname(self):
|
||||
if self._comptype == 'ULAW':
|
||||
return 'CCITT G.711 u-law'
|
||||
elif self._comptype == 'ALAW':
|
||||
return 'CCITT G.711 A-law'
|
||||
else:
|
||||
return 'not compressed'
|
||||
|
||||
def setparams(self, (nchannels, sampwidth, framerate, nframes, comptype, compname)):
|
||||
self.setnchannels(nchannels)
|
||||
self.setsampwidth(sampwidth)
|
||||
self.setframerate(framerate)
|
||||
self.setnframes(nframes)
|
||||
self.setcomptype(comptype, compname)
|
||||
|
||||
def getparams(self):
|
||||
return self.getnchannels(), self.getsampwidth(), \
|
||||
self.getframerate(), self.getnframes(), \
|
||||
self.getcomptype(), self.getcompname()
|
||||
|
||||
def tell(self):
|
||||
return self._nframeswritten
|
||||
|
||||
def writeframesraw(self, data):
|
||||
self._ensure_header_written()
|
||||
nframes = len(data) / self._framesize
|
||||
if self._comptype == 'ULAW':
|
||||
import audioop
|
||||
data = audioop.lin2ulaw(data, self._sampwidth)
|
||||
self._file.write(data)
|
||||
self._nframeswritten = self._nframeswritten + nframes
|
||||
self._datawritten = self._datawritten + len(data)
|
||||
|
||||
def writeframes(self, data):
|
||||
self.writeframesraw(data)
|
||||
if self._nframeswritten != self._nframes or \
|
||||
self._datalength != self._datawritten:
|
||||
self._patchheader()
|
||||
|
||||
def close(self):
|
||||
self._ensure_header_written()
|
||||
if self._nframeswritten != self._nframes or \
|
||||
self._datalength != self._datawritten:
|
||||
self._patchheader()
|
||||
self._file.close()
|
||||
self._file = None
|
||||
|
||||
#
|
||||
# private methods
|
||||
#
|
||||
def _ensure_header_written(self):
|
||||
if not self._nframeswritten:
|
||||
if not self._nchannels:
|
||||
raise Error, '# of channels not specified'
|
||||
if not self._sampwidth:
|
||||
raise Error, 'sample width not specified'
|
||||
if not self._framerate:
|
||||
raise Error, 'frame rate not specified'
|
||||
self._write_header()
|
||||
|
||||
def _write_header(self):
|
||||
if self._comptype == 'NONE':
|
||||
if self._sampwidth == 1:
|
||||
encoding = AUDIO_FILE_ENCODING_LINEAR_8
|
||||
self._framesize = 1
|
||||
elif self._sampwidth == 2:
|
||||
encoding = AUDIO_FILE_ENCODING_LINEAR_16
|
||||
self._framesize = 2
|
||||
elif self._sampwidth == 4:
|
||||
encoding = AUDIO_FILE_ENCODING_LINEAR_32
|
||||
self._framesize = 4
|
||||
else:
|
||||
raise Error, 'internal error'
|
||||
elif self._comptype == 'ULAW':
|
||||
encoding = AUDIO_FILE_ENCODING_MULAW_8
|
||||
self._framesize = 1
|
||||
else:
|
||||
raise Error, 'internal error'
|
||||
self._framesize = self._framesize * self._nchannels
|
||||
_write_u32(self._file, AUDIO_FILE_MAGIC)
|
||||
header_size = 25 + len(self._info)
|
||||
header_size = (header_size + 7) & ~7
|
||||
_write_u32(self._file, header_size)
|
||||
if self._nframes == AUDIO_UNKNOWN_SIZE:
|
||||
length = AUDIO_UNKNOWN_SIZE
|
||||
else:
|
||||
length = self._nframes * self._framesize
|
||||
_write_u32(self._file, length)
|
||||
self._datalength = length
|
||||
_write_u32(self._file, encoding)
|
||||
_write_u32(self._file, self._framerate)
|
||||
_write_u32(self._file, self._nchannels)
|
||||
self._file.write(self._info)
|
||||
self._file.write('\0'*(header_size - len(self._info) - 24))
|
||||
|
||||
def _patchheader(self):
|
||||
self._file.seek(8)
|
||||
_write_u32(self._file, self._datawritten)
|
||||
self._datalength = self._datawritten
|
||||
self._file.seek(0, 2)
|
||||
|
||||
def open(filename, mode):
|
||||
if mode == 'r':
|
||||
return Au_read().init(filename)
|
||||
elif mode == 'w':
|
||||
return Au_write().init(filename)
|
||||
else:
|
||||
raise Error, "mode must be 'r' or 'w'"
|
||||
|
||||
def openfp(filep, mode):
|
||||
if mode == 'r':
|
||||
return Au_read().initfp(filep)
|
||||
elif mode == 'w':
|
||||
return Au_write().initfp(filep)
|
||||
else:
|
||||
raise Error, "mode must be 'r' or 'w'"
|
||||
Loading…
Reference in New Issue