| 274 | |
| 275 | |
| 276 | class Aifc_read: |
| 277 | # Variables used in this class: |
| 278 | # |
| 279 | # These variables are available to the user though appropriate |
| 280 | # methods of this class: |
| 281 | # _file -- the open file with methods read(), close(), and seek() |
| 282 | # set through the __init__() method |
| 283 | # _nchannels -- the number of audio channels |
| 284 | # available through the getnchannels() method |
| 285 | # _nframes -- the number of audio frames |
| 286 | # available through the getnframes() method |
| 287 | # _sampwidth -- the number of bytes per audio sample |
| 288 | # available through the getsampwidth() method |
| 289 | # _framerate -- the sampling frequency |
| 290 | # available through the getframerate() method |
| 291 | # _comptype -- the AIFF-C compression type ('NONE' if AIFF) |
| 292 | # available through the getcomptype() method |
| 293 | # _compname -- the human-readable AIFF-C compression type |
| 294 | # available through the getcomptype() method |
| 295 | # _markers -- the marks in the audio file |
| 296 | # available through the getmarkers() and getmark() |
| 297 | # methods |
| 298 | # _soundpos -- the position in the audio stream |
| 299 | # available through the tell() method, set through the |
| 300 | # setpos() method |
| 301 | # |
| 302 | # These variables are used internally only: |
| 303 | # _version -- the AIFF-C version number |
| 304 | # _decomp -- the decompressor from builtin module cl |
| 305 | # _comm_chunk_read -- 1 iff the COMM chunk has been read |
| 306 | # _aifc -- 1 iff reading an AIFF-C file |
| 307 | # _ssnd_seek_needed -- 1 iff positioned correctly in audio |
| 308 | # file for readframes() |
| 309 | # _ssnd_chunk -- instantiation of a chunk class for the SSND chunk |
| 310 | # _framesize -- size of one frame in the file |
| 311 | |
| 312 | _file = None # Set here since __del__ checks it |
| 313 | |
| 314 | def initfp(self, file): |
| 315 | self._version = 0 |
| 316 | self._convert = None |
| 317 | self._markers = [] |
| 318 | self._soundpos = 0 |
| 319 | self._file = file |
| 320 | chunk = Chunk(file) |
| 321 | if chunk.getname() != b'FORM': |
| 322 | raise Error('file does not start with FORM id') |
| 323 | formdata = chunk.read(4) |
| 324 | if formdata == b'AIFF': |
| 325 | self._aifc = 0 |
| 326 | elif formdata == b'AIFC': |
| 327 | self._aifc = 1 |
| 328 | else: |
| 329 | raise Error('not an AIFF or AIFF-C file') |
| 330 | self._comm_chunk_read = 0 |
| 331 | self._ssnd_chunk = None |
| 332 | while 1: |
| 333 | self._ssnd_seek_needed = 1 |