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Diffstat (limited to 'sys/lib/python/sunau.py')
| -rw-r--r-- | sys/lib/python/sunau.py | 474 |
1 files changed, 0 insertions, 474 deletions
diff --git a/sys/lib/python/sunau.py b/sys/lib/python/sunau.py deleted file mode 100644 index 0a402955b..000000000 --- a/sys/lib/python/sunau.py +++ /dev/null @@ -1,474 +0,0 @@ -"""Stuff to parse Sun and NeXT audio files. - -An audio file consists of a header followed by the data. The structure -of the header is as follows. - - +---------------+ - | magic word | - +---------------+ - | header size | - +---------------+ - | data size | - +---------------+ - | encoding | - +---------------+ - | sample rate | - +---------------+ - | # of channels | - +---------------+ - | info | - | | - +---------------+ - -The magic word consists of the 4 characters '.snd'. Apart from the -info field, all header fields are 4 bytes in size. They are all -32-bit unsigned integers encoded in big-endian byte order. - -The header size really gives the start of the data. -The data size is the physical size of the data. From the other -parameters the number of frames can be calculated. -The encoding gives the way in which audio samples are encoded. -Possible values are listed below. -The info field currently consists of an ASCII string giving a -human-readable description of the audio file. The info field is -padded with NUL bytes to the header size. - -Usage. - -Reading audio files: - f = sunau.open(file, 'r') -where file is either the name of a file or an open file pointer. -The open file pointer must have methods read(), seek(), and close(). -When the setpos() and rewind() methods are not used, the seek() -method is not necessary. - -This returns an instance of a class with the following public methods: - getnchannels() -- returns number of audio channels (1 for - mono, 2 for stereo) - getsampwidth() -- returns sample width in bytes - getframerate() -- returns sampling frequency - getnframes() -- returns number of audio frames - getcomptype() -- returns compression type ('NONE' or 'ULAW') - getcompname() -- returns human-readable version of - compression type ('not compressed' matches 'NONE') - getparams() -- returns a tuple consisting of all of the - above in the above order - getmarkers() -- returns None (for compatibility with the - aifc module) - getmark(id) -- raises an error since the mark does not - exist (for compatibility with the aifc module) - readframes(n) -- returns at most n frames of audio - rewind() -- rewind to the beginning of the audio stream - setpos(pos) -- seek to the specified position - tell() -- return the current position - close() -- close the instance (make it unusable) -The position returned by tell() and the position given to setpos() -are compatible and have nothing to do with the actual position in the -file. -The close() method is called automatically when the class instance -is destroyed. - -Writing audio files: - f = sunau.open(file, 'w') -where file is either the name of a file or an open file pointer. -The open file pointer must have methods write(), tell(), seek(), and -close(). - -This returns an instance of a class with the following public methods: - setnchannels(n) -- set the number of channels - setsampwidth(n) -- set the sample width - setframerate(n) -- set the frame rate - setnframes(n) -- set the number of frames - setcomptype(type, name) - -- set the compression type and the - human-readable compression type - setparams(tuple)-- set all parameters at once - tell() -- return current position in output file - writeframesraw(data) - -- write audio frames without pathing up the - file header - writeframes(data) - -- write audio frames and patch up the file header - close() -- patch up the file header and close the - output file -You should set the parameters before the first writeframesraw or -writeframes. The total number of frames does not need to be set, -but when it is set to the correct value, the header does not have to -be patched up. -It is best to first set all parameters, perhaps possibly the -compression type, and then write audio frames using writeframesraw. -When all frames have been written, either call writeframes('') or -close() to patch up the sizes in the header. -The close() method is called automatically when the class instance -is destroyed. -""" - -# from <multimedia/audio_filehdr.h> -AUDIO_FILE_MAGIC = 0x2e736e64 -AUDIO_FILE_ENCODING_MULAW_8 = 1 -AUDIO_FILE_ENCODING_LINEAR_8 = 2 -AUDIO_FILE_ENCODING_LINEAR_16 = 3 -AUDIO_FILE_ENCODING_LINEAR_24 = 4 -AUDIO_FILE_ENCODING_LINEAR_32 = 5 -AUDIO_FILE_ENCODING_FLOAT = 6 -AUDIO_FILE_ENCODING_DOUBLE = 7 -AUDIO_FILE_ENCODING_ADPCM_G721 = 23 -AUDIO_FILE_ENCODING_ADPCM_G722 = 24 -AUDIO_FILE_ENCODING_ADPCM_G723_3 = 25 -AUDIO_FILE_ENCODING_ADPCM_G723_5 = 26 -AUDIO_FILE_ENCODING_ALAW_8 = 27 - -# from <multimedia/audio_hdr.h> -AUDIO_UNKNOWN_SIZE = 0xFFFFFFFFL # ((unsigned)(~0)) - -_simple_encodings = [AUDIO_FILE_ENCODING_MULAW_8, - AUDIO_FILE_ENCODING_LINEAR_8, - AUDIO_FILE_ENCODING_LINEAR_16, - AUDIO_FILE_ENCODING_LINEAR_24, - AUDIO_FILE_ENCODING_LINEAR_32, - AUDIO_FILE_ENCODING_ALAW_8] - -class Error(Exception): - pass - -def _read_u32(file): - x = 0L - for i in range(4): - byte = file.read(1) - if byte == '': - raise EOFError - x = x*256 + ord(byte) - return x - -def _write_u32(file, x): - data = [] - for i in range(4): - d, m = divmod(x, 256) - data.insert(0, m) - x = d - for i in range(4): - file.write(chr(int(data[i]))) - -class Au_read: - - def __init__(self, f): - if type(f) == type(''): - import __builtin__ - f = __builtin__.open(f, 'rb') - self.initfp(f) - - def __del__(self): - if self._file: - self.close() - - def initfp(self, file): - self._file = file - self._soundpos = 0 - magic = int(_read_u32(file)) - if magic != AUDIO_FILE_MAGIC: - raise Error, 'bad magic number' - self._hdr_size = int(_read_u32(file)) - if self._hdr_size < 24: - raise Error, 'header size too small' - if self._hdr_size > 100: - raise Error, 'header size ridiculously large' - self._data_size = _read_u32(file) - if self._data_size != AUDIO_UNKNOWN_SIZE: - self._data_size = int(self._data_size) - 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_ALAW_8): - self._sampwidth = 2 - self._framesize = 1 - elif self._encoding == AUDIO_FILE_ENCODING_LINEAR_8: - self._framesize = self._sampwidth = 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 = '' - - 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._framesize * 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 = None - -class Au_write: - - def __init__(self, f): - if type(f) == type(''): - import __builtin__ - f = __builtin__.open(f, 'wb') - self.initfp(f) - - def __del__(self): - if self._file: - self.close() - - 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 - - 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.flush() - 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(f, mode=None): - if mode is None: - if hasattr(f, 'mode'): - mode = f.mode - else: - mode = 'rb' - if mode in ('r', 'rb'): - return Au_read(f) - elif mode in ('w', 'wb'): - return Au_write(f) - else: - raise Error, "mode must be 'r', 'rb', 'w', or 'wb'" - -openfp = open |