Lib/test/test_ossaudiodev.py

   1 from test import test_support
   2 test_support.requires('audio')
   3
   4 from test.test_support import verbose, findfile, TestFailed, TestSkipped
   5
   6 import errno
   7 import fcntl
   8 import ossaudiodev
   9 import os
  10 import sys
  11 import select
  12 import sunaudio
  13 import time
  14 import audioop
  15
  16 # Arggh, AFMT_S16_NE not defined on all platforms -- seems to be a
  17 # fairly recent addition to OSS.
  18 try:
  19     from ossaudiodev import AFMT_S16_NE
  20 except ImportError:
  21     if sys.byteorder == "little":
  22         AFMT_S16_NE = ossaudiodev.AFMT_S16_LE
  23     else:
  24         AFMT_S16_NE = ossaudiodev.AFMT_S16_BE
  25
  26
  27 SND_FORMAT_MULAW_8 = 1
  28
  29 def read_sound_file(path):
  30     fp = open(path, 'rb')
  31     size, enc, rate, nchannels, extra = sunaudio.gethdr(fp)
  32     data = fp.read()
  33     fp.close()
  34
  35     if enc != SND_FORMAT_MULAW_8:
  36         print "Expect .au file with 8-bit mu-law samples"
  37         return
  38
  39     # Convert the data to 16-bit signed.
  40     data = audioop.ulaw2lin(data, 2)
  41     return (data, rate, 16, nchannels)
  42
  43
  44 def play_sound_file(data, rate, ssize, nchannels):
  45     try:
  46         dsp = ossaudiodev.open('w')
  47     except IOError, msg:
  48         if msg[0] in (errno.EACCES, errno.ENODEV, errno.EBUSY):
  49             raise TestSkipped, msg
  50         raise TestFailed, msg
  51
  52     # at least check that these methods can be invoked
  53     dsp.bufsize()
  54     dsp.obufcount()
  55     dsp.obuffree()
  56     dsp.getptr()
  57     dsp.fileno()
  58
  59     # set parameters based on .au file headers
  60     dsp.setparameters(AFMT_S16_NE, nchannels, rate)
  61     t1 = time.time()
  62     print "playing test sound file..."
  63     dsp.write(data)
  64     dsp.close()
  65     t2 = time.time()
  66     print "elapsed time: %.1f sec" % (t2-t1)
  67
  68 def test_setparameters(dsp):
  69     # Two configurations for testing:
  70     #   config1 (8-bit, mono, 8 kHz) should work on even the most
  71     #      ancient and crufty sound card, but maybe not on special-
  72     #      purpose high-end hardware
  73     #   config2 (16-bit, stereo, 44.1kHz) should work on all but the
  74     #      most ancient and crufty hardware
  75     config1 = (ossaudiodev.AFMT_U8, 1, 8000)
  76     config2 = (AFMT_S16_NE, 2, 44100)
  77
  78     for config in [config1, config2]:
  79         (fmt, channels, rate) = config
  80         if (dsp.setfmt(fmt) == fmt and
  81             dsp.channels(channels) == channels and
  82             dsp.speed(rate) == rate):
  83             break
  84     else:
  85         raise RuntimeError("unable to set audio sampling parameters: "
  86                            "you must have really weird audio hardware")
  87
  88     # setparameters() should be able to set this configuration in
  89     # either strict or non-strict mode.
  90     result = dsp.setparameters(fmt, channels, rate, False)
  91     assert result == (fmt, channels, rate), \
  92            "setparameters%r: returned %r" % (config + result)
  93     result = dsp.setparameters(fmt, channels, rate, True)
  94     assert result == (fmt, channels, rate), \
  95            "setparameters%r: returned %r" % (config + result)
  96
  97 def test_bad_setparameters(dsp):
  98
  99     # Now try some configurations that are presumably bogus: eg. 300
 100     # channels currently exceeds even Hollywood's ambitions, and
 101     # negative sampling rate is utter nonsense.  setparameters() should
 102     # accept these in non-strict mode, returning something other than
 103     # was requested, but should barf in strict mode.
 104     fmt = AFMT_S16_NE
 105     rate = 44100
 106     channels = 2
 107     for config in [(fmt, 300, rate),       # ridiculous nchannels
 108                    (fmt, -5, rate),        # impossible nchannels
 109                    (fmt, channels, -50),   # impossible rate
 110                   ]:
 111         (fmt, channels, rate) = config
 112         result = dsp.setparameters(fmt, channels, rate, False)
 113         assert result != config, \
 114                "setparameters: unexpectedly got requested configuration"
 115
 116         try:
 117             result = dsp.setparameters(fmt, channels, rate, True)
 118             raise AssertionError("setparameters: expected OSSAudioError")
 119         except ossaudiodev.OSSAudioError, err:
 120             print "setparameters: got OSSAudioError as expected"
 121
 122 def test():
 123     (data, rate, ssize, nchannels) = read_sound_file(findfile('audiotest.au'))
 124     play_sound_file(data, rate, ssize, nchannels)
 125
 126     dsp = ossaudiodev.open("w")
 127     try:
 128         test_setparameters(dsp)
 129
 130         # Disabled because it fails under Linux 2.6 with ALSA's OSS
 131         # emulation layer.
 132         #test_bad_setparameters(dsp)
 133     finally:
 134         dsp.close()
 135
 136 test()