symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/sunau.py
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/sunau.py	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,474 @@
+"""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