test_ossaudiodev.py 文件源码

def play_sound_file(self, data, rate, ssize, nchannels):
        try:
            dsp = ossaudiodev.open('w')
        except IOError, msg:
            if msg.args[0] in (errno.EACCES, errno.ENOENT,
                               errno.ENODEV, errno.EBUSY):
                raise unittest.SkipTest(msg)
            raise

        # at least check that these methods can be invoked
        dsp.bufsize()
        dsp.obufcount()
        dsp.obuffree()
        dsp.getptr()
        dsp.fileno()

        # Make sure the read-only attributes work.
        self.assertFalse(dsp.closed)
        self.assertEqual(dsp.name, "/dev/dsp")
        self.assertEqual(dsp.mode, "w", "bad dsp.mode: %r" % dsp.mode)

        # And make sure they're really read-only.
        for attr in ('closed', 'name', 'mode'):
            try:
                setattr(dsp, attr, 42)
            except TypeError:
                pass
            else:
                self.fail("dsp.%s not read-only" % attr)

        # Compute expected running time of sound sample (in seconds).
        expected_time = float(len(data)) / (ssize//8) / nchannels / rate

        # set parameters based on .au file headers
        dsp.setparameters(AFMT_S16_NE, nchannels, rate)
        self.assertTrue(abs(expected_time - 3.51) < 1e-2, expected_time)
        t1 = time.time()
        dsp.write(data)
        dsp.close()
        t2 = time.time()
        elapsed_time = t2 - t1

        percent_diff = (abs(elapsed_time - expected_time) / expected_time) * 100
        self.assertTrue(percent_diff <= 10.0,
                        "elapsed time > 10% off of expected time")