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Guido van Rossum4acc25b2000-02-02 15:10:15 +00001"""Stuff to parse AIFF-C and AIFF files.
2
3Unless explicitly stated otherwise, the description below is true
4both for AIFF-C files and AIFF files.
5
6An AIFF-C file has the following structure.
7
8 +-----------------+
9 | FORM |
10 +-----------------+
11 | <size> |
12 +----+------------+
13 | | AIFC |
14 | +------------+
15 | | <chunks> |
16 | | . |
17 | | . |
18 | | . |
19 +----+------------+
20
21An AIFF file has the string "AIFF" instead of "AIFC".
22
23A chunk consists of an identifier (4 bytes) followed by a size (4 bytes,
24big endian order), followed by the data. The size field does not include
25the size of the 8 byte header.
26
27The following chunk types are recognized.
28
29 FVER
30 <version number of AIFF-C defining document> (AIFF-C only).
31 MARK
32 <# of markers> (2 bytes)
33 list of markers:
34 <marker ID> (2 bytes, must be > 0)
35 <position> (4 bytes)
36 <marker name> ("pstring")
37 COMM
38 <# of channels> (2 bytes)
39 <# of sound frames> (4 bytes)
40 <size of the samples> (2 bytes)
41 <sampling frequency> (10 bytes, IEEE 80-bit extended
42 floating point)
43 in AIFF-C files only:
44 <compression type> (4 bytes)
45 <human-readable version of compression type> ("pstring")
46 SSND
47 <offset> (4 bytes, not used by this program)
48 <blocksize> (4 bytes, not used by this program)
49 <sound data>
50
51A pstring consists of 1 byte length, a string of characters, and 0 or 1
52byte pad to make the total length even.
53
54Usage.
55
56Reading AIFF files:
57 f = aifc.open(file, 'r')
58where file is either the name of a file or an open file pointer.
59The open file pointer must have methods read(), seek(), and close().
60In some types of audio files, if the setpos() method is not used,
61the seek() method is not necessary.
62
63This returns an instance of a class with the following public methods:
64 getnchannels() -- returns number of audio channels (1 for
65 mono, 2 for stereo)
66 getsampwidth() -- returns sample width in bytes
67 getframerate() -- returns sampling frequency
68 getnframes() -- returns number of audio frames
69 getcomptype() -- returns compression type ('NONE' for AIFF files)
70 getcompname() -- returns human-readable version of
71 compression type ('not compressed' for AIFF files)
R David Murray4d35e752013-07-25 16:12:01 -040072 getparams() -- returns a namedtuple consisting of all of the
Guido van Rossum4acc25b2000-02-02 15:10:15 +000073 above in the above order
74 getmarkers() -- get the list of marks in the audio file or None
75 if there are no marks
76 getmark(id) -- get mark with the specified id (raises an error
77 if the mark does not exist)
78 readframes(n) -- returns at most n frames of audio
79 rewind() -- rewind to the beginning of the audio stream
80 setpos(pos) -- seek to the specified position
81 tell() -- return the current position
82 close() -- close the instance (make it unusable)
83The position returned by tell(), the position given to setpos() and
84the position of marks are all compatible and have nothing to do with
Thomas Wouters7e474022000-07-16 12:04:32 +000085the actual position in the file.
Guido van Rossum4acc25b2000-02-02 15:10:15 +000086The close() method is called automatically when the class instance
87is destroyed.
88
89Writing AIFF files:
90 f = aifc.open(file, 'w')
91where file is either the name of a file or an open file pointer.
92The open file pointer must have methods write(), tell(), seek(), and
93close().
94
95This returns an instance of a class with the following public methods:
96 aiff() -- create an AIFF file (AIFF-C default)
97 aifc() -- create an AIFF-C file
98 setnchannels(n) -- set the number of channels
99 setsampwidth(n) -- set the sample width
100 setframerate(n) -- set the frame rate
101 setnframes(n) -- set the number of frames
102 setcomptype(type, name)
103 -- set the compression type and the
104 human-readable compression type
105 setparams(tuple)
106 -- set all parameters at once
107 setmark(id, pos, name)
108 -- add specified mark to the list of marks
109 tell() -- return current position in output file (useful
110 in combination with setmark())
111 writeframesraw(data)
112 -- write audio frames without pathing up the
113 file header
114 writeframes(data)
115 -- write audio frames and patch up the file header
116 close() -- patch up the file header and close the
117 output file
118You should set the parameters before the first writeframesraw or
119writeframes. The total number of frames does not need to be set,
120but when it is set to the correct value, the header does not have to
121be patched up.
122It is best to first set all parameters, perhaps possibly the
123compression type, and then write audio frames using writeframesraw.
124When all frames have been written, either call writeframes('') or
125close() to patch up the sizes in the header.
126Marks can be added anytime. If there are any marks, ypu must call
127close() after all frames have been written.
128The close() method is called automatically when the class instance
129is destroyed.
130
131When a file is opened with the extension '.aiff', an AIFF file is
132written, otherwise an AIFF-C file is written. This default can be
133changed by calling aiff() or aifc() before the first writeframes or
134writeframesraw.
135"""
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000136
Guido van Rossum36bb1811996-12-31 05:57:34 +0000137import struct
Georg Brandl1a3284e2007-12-02 09:40:06 +0000138import builtins
Ezio Melotti48d578c2012-03-12 23:57:18 +0200139import warnings
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000140
Georg Brandl2095cfe2008-06-07 19:01:03 +0000141__all__ = ["Error", "open", "openfp"]
Skip Montanaroe99d5ea2001-01-20 19:54:20 +0000142
Fred Drake227b1202000-08-17 05:06:49 +0000143class Error(Exception):
144 pass
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000145
Guido van Rossume2a383d2007-01-15 16:59:06 +0000146_AIFC_version = 0xA2805140 # Version 1 of AIFF-C
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000147
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000148def _read_long(file):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000149 try:
150 return struct.unpack('>l', file.read(4))[0]
151 except struct.error:
152 raise EOFError
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000153
154def _read_ulong(file):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000155 try:
156 return struct.unpack('>L', file.read(4))[0]
157 except struct.error:
158 raise EOFError
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000159
160def _read_short(file):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000161 try:
162 return struct.unpack('>h', file.read(2))[0]
163 except struct.error:
164 raise EOFError
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000165
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100166def _read_ushort(file):
167 try:
168 return struct.unpack('>H', file.read(2))[0]
169 except struct.error:
170 raise EOFError
171
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000172def _read_string(file):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000173 length = ord(file.read(1))
174 if length == 0:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000175 data = b''
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000176 else:
177 data = file.read(length)
178 if length & 1 == 0:
179 dummy = file.read(1)
180 return data
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000181
182_HUGE_VAL = 1.79769313486231e+308 # See <limits.h>
183
184def _read_float(f): # 10 bytes
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000185 expon = _read_short(f) # 2 bytes
186 sign = 1
187 if expon < 0:
188 sign = -1
189 expon = expon + 0x8000
190 himant = _read_ulong(f) # 4 bytes
191 lomant = _read_ulong(f) # 4 bytes
192 if expon == himant == lomant == 0:
193 f = 0.0
194 elif expon == 0x7FFF:
195 f = _HUGE_VAL
196 else:
197 expon = expon - 16383
Guido van Rossume2a383d2007-01-15 16:59:06 +0000198 f = (himant * 0x100000000 + lomant) * pow(2.0, expon - 63)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000199 return sign * f
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000200
201def _write_short(f, x):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000202 f.write(struct.pack('>h', x))
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000203
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100204def _write_ushort(f, x):
205 f.write(struct.pack('>H', x))
206
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000207def _write_long(f, x):
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100208 f.write(struct.pack('>l', x))
209
210def _write_ulong(f, x):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000211 f.write(struct.pack('>L', x))
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000212
213def _write_string(f, s):
Thomas Wouters4d70c3d2006-06-08 14:42:34 +0000214 if len(s) > 255:
215 raise ValueError("string exceeds maximum pstring length")
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100216 f.write(struct.pack('B', len(s)))
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000217 f.write(s)
218 if len(s) & 1 == 0:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000219 f.write(b'\x00')
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000220
221def _write_float(f, x):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000222 import math
223 if x < 0:
224 sign = 0x8000
225 x = x * -1
226 else:
227 sign = 0
228 if x == 0:
229 expon = 0
230 himant = 0
231 lomant = 0
232 else:
233 fmant, expon = math.frexp(x)
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100234 if expon > 16384 or fmant >= 1 or fmant != fmant: # Infinity or NaN
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000235 expon = sign|0x7FFF
236 himant = 0
237 lomant = 0
238 else: # Finite
239 expon = expon + 16382
240 if expon < 0: # denormalized
241 fmant = math.ldexp(fmant, expon)
242 expon = 0
243 expon = expon | sign
244 fmant = math.ldexp(fmant, 32)
245 fsmant = math.floor(fmant)
Guido van Rossume2a383d2007-01-15 16:59:06 +0000246 himant = int(fsmant)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000247 fmant = math.ldexp(fmant - fsmant, 32)
248 fsmant = math.floor(fmant)
Guido van Rossume2a383d2007-01-15 16:59:06 +0000249 lomant = int(fsmant)
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100250 _write_ushort(f, expon)
251 _write_ulong(f, himant)
252 _write_ulong(f, lomant)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000253
Guido van Rossum8ea7bb81999-06-09 13:32:28 +0000254from chunk import Chunk
R David Murray4d35e752013-07-25 16:12:01 -0400255from collections import namedtuple
256
257_aifc_params = namedtuple('_aifc_params',
258 'nchannels sampwidth framerate nframes comptype compname')
259
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000260
Guido van Rossumd3166071993-05-24 14:16:22 +0000261class Aifc_read:
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000262 # Variables used in this class:
263 #
264 # These variables are available to the user though appropriate
265 # methods of this class:
266 # _file -- the open file with methods read(), close(), and seek()
267 # set through the __init__() method
268 # _nchannels -- the number of audio channels
269 # available through the getnchannels() method
270 # _nframes -- the number of audio frames
271 # available through the getnframes() method
272 # _sampwidth -- the number of bytes per audio sample
273 # available through the getsampwidth() method
274 # _framerate -- the sampling frequency
275 # available through the getframerate() method
276 # _comptype -- the AIFF-C compression type ('NONE' if AIFF)
277 # available through the getcomptype() method
278 # _compname -- the human-readable AIFF-C compression type
279 # available through the getcomptype() method
280 # _markers -- the marks in the audio file
281 # available through the getmarkers() and getmark()
282 # methods
283 # _soundpos -- the position in the audio stream
284 # available through the tell() method, set through the
285 # setpos() method
286 #
287 # These variables are used internally only:
288 # _version -- the AIFF-C version number
289 # _decomp -- the decompressor from builtin module cl
290 # _comm_chunk_read -- 1 iff the COMM chunk has been read
291 # _aifc -- 1 iff reading an AIFF-C file
292 # _ssnd_seek_needed -- 1 iff positioned correctly in audio
293 # file for readframes()
294 # _ssnd_chunk -- instantiation of a chunk class for the SSND chunk
295 # _framesize -- size of one frame in the file
Sjoerd Mullender2a451411993-12-20 09:36:01 +0000296
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000297 def initfp(self, file):
298 self._version = 0
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000299 self._convert = None
300 self._markers = []
301 self._soundpos = 0
R. David Murray99352742009-05-07 18:24:38 +0000302 self._file = file
303 chunk = Chunk(file)
304 if chunk.getname() != b'FORM':
Collin Winterce36ad82007-08-30 01:19:48 +0000305 raise Error('file does not start with FORM id')
R. David Murray99352742009-05-07 18:24:38 +0000306 formdata = chunk.read(4)
Georg Brandl2095cfe2008-06-07 19:01:03 +0000307 if formdata == b'AIFF':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000308 self._aifc = 0
Georg Brandl2095cfe2008-06-07 19:01:03 +0000309 elif formdata == b'AIFC':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000310 self._aifc = 1
311 else:
Collin Winterce36ad82007-08-30 01:19:48 +0000312 raise Error('not an AIFF or AIFF-C file')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000313 self._comm_chunk_read = 0
314 while 1:
315 self._ssnd_seek_needed = 1
316 try:
317 chunk = Chunk(self._file)
318 except EOFError:
319 break
320 chunkname = chunk.getname()
Georg Brandl2095cfe2008-06-07 19:01:03 +0000321 if chunkname == b'COMM':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000322 self._read_comm_chunk(chunk)
323 self._comm_chunk_read = 1
Georg Brandl2095cfe2008-06-07 19:01:03 +0000324 elif chunkname == b'SSND':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000325 self._ssnd_chunk = chunk
326 dummy = chunk.read(8)
327 self._ssnd_seek_needed = 0
Georg Brandl2095cfe2008-06-07 19:01:03 +0000328 elif chunkname == b'FVER':
Guido van Rossum820819c2002-08-12 22:11:28 +0000329 self._version = _read_ulong(chunk)
Georg Brandl2095cfe2008-06-07 19:01:03 +0000330 elif chunkname == b'MARK':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000331 self._readmark(chunk)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000332 chunk.skip()
333 if not self._comm_chunk_read or not self._ssnd_chunk:
Collin Winterce36ad82007-08-30 01:19:48 +0000334 raise Error('COMM chunk and/or SSND chunk missing')
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000335
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000336 def __init__(self, f):
Georg Brandl2095cfe2008-06-07 19:01:03 +0000337 if isinstance(f, str):
Georg Brandl1a3284e2007-12-02 09:40:06 +0000338 f = builtins.open(f, 'rb')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000339 # else, assume it is an open file object already
340 self.initfp(f)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000341
Serhiy Storchaka44c66c72012-12-29 22:54:49 +0200342 def __enter__(self):
343 return self
344
345 def __exit__(self, *args):
346 self.close()
347
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000348 #
349 # User visible methods.
350 #
351 def getfp(self):
352 return self._file
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000353
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000354 def rewind(self):
355 self._ssnd_seek_needed = 1
356 self._soundpos = 0
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000357
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000358 def close(self):
Benjamin Peterson1d1285d2009-05-07 11:53:38 +0000359 self._file.close()
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000360
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000361 def tell(self):
362 return self._soundpos
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000363
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000364 def getnchannels(self):
365 return self._nchannels
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000366
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000367 def getnframes(self):
368 return self._nframes
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000369
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000370 def getsampwidth(self):
371 return self._sampwidth
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000372
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000373 def getframerate(self):
374 return self._framerate
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000375
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000376 def getcomptype(self):
377 return self._comptype
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000378
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000379 def getcompname(self):
380 return self._compname
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000381
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000382## def getversion(self):
383## return self._version
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000384
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000385 def getparams(self):
R David Murray4d35e752013-07-25 16:12:01 -0400386 return _aifc_params(self.getnchannels(), self.getsampwidth(),
387 self.getframerate(), self.getnframes(),
388 self.getcomptype(), self.getcompname())
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000389
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000390 def getmarkers(self):
391 if len(self._markers) == 0:
392 return None
393 return self._markers
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000394
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000395 def getmark(self, id):
396 for marker in self._markers:
397 if id == marker[0]:
398 return marker
Georg Brandl2095cfe2008-06-07 19:01:03 +0000399 raise Error('marker {0!r} does not exist'.format(id))
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000400
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000401 def setpos(self, pos):
402 if pos < 0 or pos > self._nframes:
Collin Winterce36ad82007-08-30 01:19:48 +0000403 raise Error('position not in range')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000404 self._soundpos = pos
405 self._ssnd_seek_needed = 1
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000406
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000407 def readframes(self, nframes):
408 if self._ssnd_seek_needed:
409 self._ssnd_chunk.seek(0)
410 dummy = self._ssnd_chunk.read(8)
411 pos = self._soundpos * self._framesize
412 if pos:
Guido van Rossum2663c132000-03-07 15:19:31 +0000413 self._ssnd_chunk.seek(pos + 8)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000414 self._ssnd_seek_needed = 0
415 if nframes == 0:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000416 return b''
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000417 data = self._ssnd_chunk.read(nframes * self._framesize)
418 if self._convert and data:
419 data = self._convert(data)
Georg Brandl2095cfe2008-06-07 19:01:03 +0000420 self._soundpos = self._soundpos + len(data) // (self._nchannels
421 * self._sampwidth)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000422 return data
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000423
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000424 #
425 # Internal methods.
426 #
Sjoerd Mullender2a451411993-12-20 09:36:01 +0000427
Georg Brandl2095cfe2008-06-07 19:01:03 +0000428 def _alaw2lin(self, data):
429 import audioop
430 return audioop.alaw2lin(data, 2)
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000431
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000432 def _ulaw2lin(self, data):
433 import audioop
434 return audioop.ulaw2lin(data, 2)
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000435
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000436 def _adpcm2lin(self, data):
437 import audioop
438 if not hasattr(self, '_adpcmstate'):
439 # first time
440 self._adpcmstate = None
Georg Brandl2095cfe2008-06-07 19:01:03 +0000441 data, self._adpcmstate = audioop.adpcm2lin(data, 2, self._adpcmstate)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000442 return data
Sjoerd Mullender1f057541994-09-06 16:17:51 +0000443
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000444 def _read_comm_chunk(self, chunk):
445 self._nchannels = _read_short(chunk)
446 self._nframes = _read_long(chunk)
Georg Brandl2095cfe2008-06-07 19:01:03 +0000447 self._sampwidth = (_read_short(chunk) + 7) // 8
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000448 self._framerate = int(_read_float(chunk))
449 self._framesize = self._nchannels * self._sampwidth
450 if self._aifc:
451 #DEBUG: SGI's soundeditor produces a bad size :-(
452 kludge = 0
453 if chunk.chunksize == 18:
454 kludge = 1
Ezio Melotti48d578c2012-03-12 23:57:18 +0200455 warnings.warn('Warning: bad COMM chunk size')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000456 chunk.chunksize = 23
457 #DEBUG end
458 self._comptype = chunk.read(4)
459 #DEBUG start
460 if kludge:
461 length = ord(chunk.file.read(1))
462 if length & 1 == 0:
463 length = length + 1
464 chunk.chunksize = chunk.chunksize + length
465 chunk.file.seek(-1, 1)
466 #DEBUG end
467 self._compname = _read_string(chunk)
Georg Brandl2095cfe2008-06-07 19:01:03 +0000468 if self._comptype != b'NONE':
469 if self._comptype == b'G722':
470 self._convert = self._adpcm2lin
471 self._framesize = self._framesize // 4
472 elif self._comptype in (b'ulaw', b'ULAW'):
473 self._convert = self._ulaw2lin
474 self._framesize = self._framesize // 2
475 elif self._comptype in (b'alaw', b'ALAW'):
476 self._convert = self._alaw2lin
477 self._framesize = self._framesize // 2
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000478 else:
Collin Winterce36ad82007-08-30 01:19:48 +0000479 raise Error('unsupported compression type')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000480 else:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000481 self._comptype = b'NONE'
482 self._compname = b'not compressed'
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000483
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000484 def _readmark(self, chunk):
485 nmarkers = _read_short(chunk)
486 # Some files appear to contain invalid counts.
487 # Cope with this by testing for EOF.
488 try:
489 for i in range(nmarkers):
490 id = _read_short(chunk)
491 pos = _read_long(chunk)
492 name = _read_string(chunk)
493 if pos or name:
494 # some files appear to have
495 # dummy markers consisting of
496 # a position 0 and name ''
497 self._markers.append((id, pos, name))
498 except EOFError:
Ezio Melotti48d578c2012-03-12 23:57:18 +0200499 w = ('Warning: MARK chunk contains only %s marker%s instead of %s' %
500 (len(self._markers), '' if len(self._markers) == 1 else 's',
501 nmarkers))
502 warnings.warn(w)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000503
Guido van Rossumd3166071993-05-24 14:16:22 +0000504class Aifc_write:
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000505 # Variables used in this class:
506 #
507 # These variables are user settable through appropriate methods
508 # of this class:
509 # _file -- the open file with methods write(), close(), tell(), seek()
510 # set through the __init__() method
511 # _comptype -- the AIFF-C compression type ('NONE' in AIFF)
512 # set through the setcomptype() or setparams() method
513 # _compname -- the human-readable AIFF-C compression type
514 # set through the setcomptype() or setparams() method
515 # _nchannels -- the number of audio channels
516 # set through the setnchannels() or setparams() method
517 # _sampwidth -- the number of bytes per audio sample
518 # set through the setsampwidth() or setparams() method
519 # _framerate -- the sampling frequency
520 # set through the setframerate() or setparams() method
521 # _nframes -- the number of audio frames written to the header
522 # set through the setnframes() or setparams() method
523 # _aifc -- whether we're writing an AIFF-C file or an AIFF file
524 # set through the aifc() method, reset through the
525 # aiff() method
526 #
527 # These variables are used internally only:
528 # _version -- the AIFF-C version number
529 # _comp -- the compressor from builtin module cl
530 # _nframeswritten -- the number of audio frames actually written
531 # _datalength -- the size of the audio samples written to the header
532 # _datawritten -- the size of the audio samples actually written
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000533
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000534 def __init__(self, f):
Georg Brandl2095cfe2008-06-07 19:01:03 +0000535 if isinstance(f, str):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000536 filename = f
Georg Brandl1a3284e2007-12-02 09:40:06 +0000537 f = builtins.open(f, 'wb')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000538 else:
539 # else, assume it is an open file object already
540 filename = '???'
541 self.initfp(f)
542 if filename[-5:] == '.aiff':
543 self._aifc = 0
544 else:
545 self._aifc = 1
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000546
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000547 def initfp(self, file):
548 self._file = file
549 self._version = _AIFC_version
Georg Brandl2095cfe2008-06-07 19:01:03 +0000550 self._comptype = b'NONE'
551 self._compname = b'not compressed'
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000552 self._convert = None
553 self._nchannels = 0
554 self._sampwidth = 0
555 self._framerate = 0
556 self._nframes = 0
557 self._nframeswritten = 0
558 self._datawritten = 0
559 self._datalength = 0
560 self._markers = []
561 self._marklength = 0
562 self._aifc = 1 # AIFF-C is default
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000563
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000564 def __del__(self):
Sandro Tosi70efbef2012-01-01 22:53:08 +0100565 self.close()
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000566
Serhiy Storchaka44c66c72012-12-29 22:54:49 +0200567 def __enter__(self):
568 return self
569
570 def __exit__(self, *args):
571 self.close()
572
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000573 #
574 # User visible methods.
575 #
576 def aiff(self):
577 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000578 raise Error('cannot change parameters after starting to write')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000579 self._aifc = 0
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000580
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000581 def aifc(self):
582 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000583 raise Error('cannot change parameters after starting to write')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000584 self._aifc = 1
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000585
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000586 def setnchannels(self, nchannels):
587 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000588 raise Error('cannot change parameters after starting to write')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000589 if nchannels < 1:
Collin Winterce36ad82007-08-30 01:19:48 +0000590 raise Error('bad # of channels')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000591 self._nchannels = nchannels
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000592
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000593 def getnchannels(self):
594 if not self._nchannels:
Collin Winterce36ad82007-08-30 01:19:48 +0000595 raise Error('number of channels not set')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000596 return self._nchannels
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000597
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000598 def setsampwidth(self, sampwidth):
599 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000600 raise Error('cannot change parameters after starting to write')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000601 if sampwidth < 1 or sampwidth > 4:
Collin Winterce36ad82007-08-30 01:19:48 +0000602 raise Error('bad sample width')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000603 self._sampwidth = sampwidth
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000604
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000605 def getsampwidth(self):
606 if not self._sampwidth:
Collin Winterce36ad82007-08-30 01:19:48 +0000607 raise Error('sample width not set')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000608 return self._sampwidth
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000609
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000610 def setframerate(self, framerate):
611 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000612 raise Error('cannot change parameters after starting to write')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000613 if framerate <= 0:
Collin Winterce36ad82007-08-30 01:19:48 +0000614 raise Error('bad frame rate')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000615 self._framerate = framerate
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000616
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000617 def getframerate(self):
618 if not self._framerate:
Collin Winterce36ad82007-08-30 01:19:48 +0000619 raise Error('frame rate not set')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000620 return self._framerate
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000621
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000622 def setnframes(self, nframes):
623 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000624 raise Error('cannot change parameters after starting to write')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000625 self._nframes = nframes
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000626
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000627 def getnframes(self):
628 return self._nframeswritten
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000629
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000630 def setcomptype(self, comptype, compname):
631 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000632 raise Error('cannot change parameters after starting to write')
Georg Brandl2095cfe2008-06-07 19:01:03 +0000633 if comptype not in (b'NONE', b'ulaw', b'ULAW',
634 b'alaw', b'ALAW', b'G722'):
Collin Winterce36ad82007-08-30 01:19:48 +0000635 raise Error('unsupported compression type')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000636 self._comptype = comptype
637 self._compname = compname
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000638
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000639 def getcomptype(self):
640 return self._comptype
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000641
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000642 def getcompname(self):
643 return self._compname
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000644
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000645## def setversion(self, version):
646## if self._nframeswritten:
647## raise Error, 'cannot change parameters after starting to write'
648## self._version = version
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000649
Guido van Rossum1bc535d2007-05-15 18:46:22 +0000650 def setparams(self, params):
651 nchannels, sampwidth, framerate, nframes, comptype, compname = params
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000652 if self._nframeswritten:
Collin Winterce36ad82007-08-30 01:19:48 +0000653 raise Error('cannot change parameters after starting to write')
Georg Brandl2095cfe2008-06-07 19:01:03 +0000654 if comptype not in (b'NONE', b'ulaw', b'ULAW',
655 b'alaw', b'ALAW', b'G722'):
Collin Winterce36ad82007-08-30 01:19:48 +0000656 raise Error('unsupported compression type')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000657 self.setnchannels(nchannels)
658 self.setsampwidth(sampwidth)
659 self.setframerate(framerate)
660 self.setnframes(nframes)
661 self.setcomptype(comptype, compname)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000662
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000663 def getparams(self):
664 if not self._nchannels or not self._sampwidth or not self._framerate:
Collin Winterce36ad82007-08-30 01:19:48 +0000665 raise Error('not all parameters set')
R David Murray4d35e752013-07-25 16:12:01 -0400666 return _aifc_params(self._nchannels, self._sampwidth, self._framerate,
667 self._nframes, self._comptype, self._compname)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000668
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000669 def setmark(self, id, pos, name):
670 if id <= 0:
Collin Winterce36ad82007-08-30 01:19:48 +0000671 raise Error('marker ID must be > 0')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000672 if pos < 0:
Collin Winterce36ad82007-08-30 01:19:48 +0000673 raise Error('marker position must be >= 0')
Sandro Tosi70efbef2012-01-01 22:53:08 +0100674 if not isinstance(name, bytes):
675 raise Error('marker name must be bytes')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000676 for i in range(len(self._markers)):
677 if id == self._markers[i][0]:
678 self._markers[i] = id, pos, name
679 return
680 self._markers.append((id, pos, name))
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000681
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000682 def getmark(self, id):
683 for marker in self._markers:
684 if id == marker[0]:
685 return marker
Georg Brandl2095cfe2008-06-07 19:01:03 +0000686 raise Error('marker {0!r} does not exist'.format(id))
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000687
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000688 def getmarkers(self):
689 if len(self._markers) == 0:
690 return None
691 return self._markers
Tim Peters146965a2001-01-14 18:09:23 +0000692
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000693 def tell(self):
694 return self._nframeswritten
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000695
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000696 def writeframesraw(self, data):
697 self._ensure_header_written(len(data))
Georg Brandl2095cfe2008-06-07 19:01:03 +0000698 nframes = len(data) // (self._sampwidth * self._nchannels)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000699 if self._convert:
700 data = self._convert(data)
701 self._file.write(data)
702 self._nframeswritten = self._nframeswritten + nframes
703 self._datawritten = self._datawritten + len(data)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000704
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000705 def writeframes(self, data):
706 self.writeframesraw(data)
707 if self._nframeswritten != self._nframes or \
708 self._datalength != self._datawritten:
709 self._patchheader()
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000710
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000711 def close(self):
Serhiy Storchaka051722d2012-12-29 22:30:56 +0200712 if self._file is None:
713 return
714 try:
Sandro Tosi70efbef2012-01-01 22:53:08 +0100715 self._ensure_header_written(0)
716 if self._datawritten & 1:
717 # quick pad to even size
718 self._file.write(b'\x00')
719 self._datawritten = self._datawritten + 1
720 self._writemarkers()
721 if self._nframeswritten != self._nframes or \
722 self._datalength != self._datawritten or \
723 self._marklength:
724 self._patchheader()
Serhiy Storchaka051722d2012-12-29 22:30:56 +0200725 finally:
Sandro Tosi70efbef2012-01-01 22:53:08 +0100726 # Prevent ref cycles
727 self._convert = None
Serhiy Storchaka051722d2012-12-29 22:30:56 +0200728 f = self._file
Sandro Tosi70efbef2012-01-01 22:53:08 +0100729 self._file = None
Serhiy Storchaka051722d2012-12-29 22:30:56 +0200730 f.close()
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000731
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000732 #
733 # Internal methods.
734 #
Sjoerd Mullender2a451411993-12-20 09:36:01 +0000735
Georg Brandl2095cfe2008-06-07 19:01:03 +0000736 def _lin2alaw(self, data):
737 import audioop
738 return audioop.lin2alaw(data, 2)
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000739
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000740 def _lin2ulaw(self, data):
741 import audioop
742 return audioop.lin2ulaw(data, 2)
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000743
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000744 def _lin2adpcm(self, data):
745 import audioop
746 if not hasattr(self, '_adpcmstate'):
747 self._adpcmstate = None
Georg Brandl2095cfe2008-06-07 19:01:03 +0000748 data, self._adpcmstate = audioop.lin2adpcm(data, 2, self._adpcmstate)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000749 return data
Sjoerd Mullender1f057541994-09-06 16:17:51 +0000750
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000751 def _ensure_header_written(self, datasize):
752 if not self._nframeswritten:
Sandro Tosibdd53542012-01-01 18:04:37 +0100753 if self._comptype in (b'ULAW', b'ulaw', b'ALAW', b'alaw', b'G722'):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000754 if not self._sampwidth:
755 self._sampwidth = 2
756 if self._sampwidth != 2:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000757 raise Error('sample width must be 2 when compressing '
Sandro Tosibdd53542012-01-01 18:04:37 +0100758 'with ulaw/ULAW, alaw/ALAW or G7.22 (ADPCM)')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000759 if not self._nchannels:
Collin Winterce36ad82007-08-30 01:19:48 +0000760 raise Error('# channels not specified')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000761 if not self._sampwidth:
Collin Winterce36ad82007-08-30 01:19:48 +0000762 raise Error('sample width not specified')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000763 if not self._framerate:
Collin Winterce36ad82007-08-30 01:19:48 +0000764 raise Error('sampling rate not specified')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000765 self._write_header(datasize)
Guido van Rossum52fc1f61993-06-17 12:38:10 +0000766
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000767 def _init_compression(self):
Georg Brandl2095cfe2008-06-07 19:01:03 +0000768 if self._comptype == b'G722':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000769 self._convert = self._lin2adpcm
Georg Brandl2095cfe2008-06-07 19:01:03 +0000770 elif self._comptype in (b'ulaw', b'ULAW'):
771 self._convert = self._lin2ulaw
772 elif self._comptype in (b'alaw', b'ALAW'):
773 self._convert = self._lin2alaw
Sjoerd Mullender43bf0bc1993-12-13 11:42:39 +0000774
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000775 def _write_header(self, initlength):
Georg Brandl2095cfe2008-06-07 19:01:03 +0000776 if self._aifc and self._comptype != b'NONE':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000777 self._init_compression()
Georg Brandl2095cfe2008-06-07 19:01:03 +0000778 self._file.write(b'FORM')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000779 if not self._nframes:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000780 self._nframes = initlength // (self._nchannels * self._sampwidth)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000781 self._datalength = self._nframes * self._nchannels * self._sampwidth
782 if self._datalength & 1:
783 self._datalength = self._datalength + 1
784 if self._aifc:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000785 if self._comptype in (b'ulaw', b'ULAW', b'alaw', b'ALAW'):
786 self._datalength = self._datalength // 2
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000787 if self._datalength & 1:
788 self._datalength = self._datalength + 1
Georg Brandl2095cfe2008-06-07 19:01:03 +0000789 elif self._comptype == b'G722':
790 self._datalength = (self._datalength + 3) // 4
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000791 if self._datalength & 1:
792 self._datalength = self._datalength + 1
793 self._form_length_pos = self._file.tell()
794 commlength = self._write_form_length(self._datalength)
795 if self._aifc:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000796 self._file.write(b'AIFC')
797 self._file.write(b'FVER')
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100798 _write_ulong(self._file, 4)
799 _write_ulong(self._file, self._version)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000800 else:
Georg Brandl2095cfe2008-06-07 19:01:03 +0000801 self._file.write(b'AIFF')
802 self._file.write(b'COMM')
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100803 _write_ulong(self._file, commlength)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000804 _write_short(self._file, self._nchannels)
805 self._nframes_pos = self._file.tell()
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100806 _write_ulong(self._file, self._nframes)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000807 _write_short(self._file, self._sampwidth * 8)
808 _write_float(self._file, self._framerate)
809 if self._aifc:
810 self._file.write(self._comptype)
811 _write_string(self._file, self._compname)
Georg Brandl2095cfe2008-06-07 19:01:03 +0000812 self._file.write(b'SSND')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000813 self._ssnd_length_pos = self._file.tell()
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100814 _write_ulong(self._file, self._datalength + 8)
815 _write_ulong(self._file, 0)
816 _write_ulong(self._file, 0)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000817
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000818 def _write_form_length(self, datalength):
819 if self._aifc:
820 commlength = 18 + 5 + len(self._compname)
821 if commlength & 1:
822 commlength = commlength + 1
823 verslength = 12
824 else:
825 commlength = 18
826 verslength = 0
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100827 _write_ulong(self._file, 4 + verslength + self._marklength + \
828 8 + commlength + 16 + datalength)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000829 return commlength
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000830
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000831 def _patchheader(self):
832 curpos = self._file.tell()
833 if self._datawritten & 1:
834 datalength = self._datawritten + 1
Georg Brandl2095cfe2008-06-07 19:01:03 +0000835 self._file.write(b'\x00')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000836 else:
837 datalength = self._datawritten
838 if datalength == self._datalength and \
839 self._nframes == self._nframeswritten and \
840 self._marklength == 0:
841 self._file.seek(curpos, 0)
842 return
843 self._file.seek(self._form_length_pos, 0)
844 dummy = self._write_form_length(datalength)
845 self._file.seek(self._nframes_pos, 0)
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100846 _write_ulong(self._file, self._nframeswritten)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000847 self._file.seek(self._ssnd_length_pos, 0)
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100848 _write_ulong(self._file, datalength + 8)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000849 self._file.seek(curpos, 0)
850 self._nframes = self._nframeswritten
851 self._datalength = datalength
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000852
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000853 def _writemarkers(self):
854 if len(self._markers) == 0:
855 return
Georg Brandl2095cfe2008-06-07 19:01:03 +0000856 self._file.write(b'MARK')
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000857 length = 2
858 for marker in self._markers:
859 id, pos, name = marker
860 length = length + len(name) + 1 + 6
861 if len(name) & 1 == 0:
862 length = length + 1
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100863 _write_ulong(self._file, length)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000864 self._marklength = length + 8
865 _write_short(self._file, len(self._markers))
866 for marker in self._markers:
867 id, pos, name = marker
868 _write_short(self._file, id)
Antoine Pitrou03757ec2012-01-17 17:13:04 +0100869 _write_ulong(self._file, pos)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000870 _write_string(self._file, name)
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000871
Fred Drake43161351999-06-22 21:23:23 +0000872def open(f, mode=None):
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000873 if mode is None:
874 if hasattr(f, 'mode'):
875 mode = f.mode
876 else:
877 mode = 'rb'
878 if mode in ('r', 'rb'):
879 return Aifc_read(f)
880 elif mode in ('w', 'wb'):
881 return Aifc_write(f)
882 else:
Collin Winterce36ad82007-08-30 01:19:48 +0000883 raise Error("mode must be 'r', 'rb', 'w', or 'wb'")
Sjoerd Mullendereeabe7e1993-01-22 12:53:11 +0000884
Guido van Rossum7bc817d1993-12-17 15:25:27 +0000885openfp = open # B/W compatibility
Guido van Rossum36bb1811996-12-31 05:57:34 +0000886
887if __name__ == '__main__':
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000888 import sys
889 if not sys.argv[1:]:
890 sys.argv.append('/usr/demos/data/audio/bach.aiff')
891 fn = sys.argv[1]
892 f = open(fn, 'r')
Guido van Rossumbe19ed72007-02-09 05:37:30 +0000893 print("Reading", fn)
894 print("nchannels =", f.getnchannels())
895 print("nframes =", f.getnframes())
896 print("sampwidth =", f.getsampwidth())
897 print("framerate =", f.getframerate())
898 print("comptype =", f.getcomptype())
899 print("compname =", f.getcompname())
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000900 if sys.argv[2:]:
901 gn = sys.argv[2]
Guido van Rossumbe19ed72007-02-09 05:37:30 +0000902 print("Writing", gn)
Guido van Rossum4acc25b2000-02-02 15:10:15 +0000903 g = open(gn, 'w')
904 g.setparams(f.getparams())
905 while 1:
906 data = f.readframes(1024)
907 if not data:
908 break
909 g.writeframes(data)
910 g.close()
911 f.close()
Guido van Rossumbe19ed72007-02-09 05:37:30 +0000912 print("Done.")