Demo/sgi/al/playaiff.py

   1 import aiff
   2 import al
   3 import sys
   4 import time
   5
   6 def main():
   7         v = 1
   8         c = al.newconfig()
   9         nchannels = c.getchannels()
  10         nsampframes = 0 # ???
  11         sampwidth = c.getwidth()
  12         samprate = 0.0 # unknown
  13         filename = sys.argv[1]
  14         f = open(filename, 'r')
  15         type, totalsize = aiff.read_chunk_header(f)
  16         if type <> 'FORM':
  17                 raise aiff.Error, 'FORM chunk expected at start of file'
  18         aiff.read_form_chunk(f)
  19         while 1:
  20                 try:
  21                         type, size = aiff.read_chunk_header(f)
  22                 except EOFError:
  23                         break
  24                 if v: print 'header:', `type`, size
  25                 if type == 'COMM':
  26                         nchannels, nsampframes, sampwidth, samprate = \
  27                                 aiff.read_comm_chunk(f)
  28                         if v: print nchannels, nsampframes, sampwidth, samprate
  29                 elif type == 'SSND':
  30                         offset, blocksize = aiff.read_ssnd_chunk(f)
  31                         if v: print offset, blocksize
  32                         data = f.read(size-8)
  33                         if size%2: void = f.read(1)
  34                         p = makeport(nchannels, sampwidth, samprate)
  35                         play(p, data, offset, blocksize)
  36                 elif type in aiff.skiplist:
  37                         aiff.skip_chunk(f, size)
  38                 else:
  39                         raise aiff.Error, 'bad chunk type ' + type
  40
  41 def makeport(nchannels, sampwidth, samprate):
  42         c = al.newconfig()
  43         c.setchannels(nchannels)
  44         c.setwidth(sampwidth/8)
  45         # can't set the rate...
  46         p = al.openport('', 'w', c)
  47         return p
  48
  49 def play(p, data, offset, blocksize):
  50         data = data[offset:]
  51         p.writesamps(data)
  52         while p.getfilled() > 0: time.sleep(0.01)
  53
  54 main()