def test_lin2ulaw(self):
self.assertEqual(audioop.lin2ulaw(datas[1], 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(datas[2], 2),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
self.assertEqual(audioop.lin2ulaw(datas[4], 4),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
python类lin2ulaw()的实例源码
def test_ulaw2lin(self):
encoded = b'\x00\x0e\x28\x3f\x57\x6a\x76\x7c\x7e\x7f'\
b'\x80\x8e\xa8\xbf\xd7\xea\xf6\xfc\xfe\xff'
src = [-8031, -4447, -1471, -495, -163, -53, -18, -6, -2, 0,
8031, 4447, 1471, 495, 163, 53, 18, 6, 2, 0]
for w in 1, 2, 4:
self.assertEqual(audioop.ulaw2lin(encoded, w),
packs[w](*(x << (w * 8) >> 14 for x in src)))
# Current u-law implementation has two codes fo 0: 0x7f and 0xff.
encoded = bytes(range(127)) + bytes(range(128, 256))
for w in 2, 4:
decoded = audioop.ulaw2lin(encoded, w)
self.assertEqual(audioop.lin2ulaw(decoded, w), encoded)
def open_input(filename):
stream = wave.open(filename,"rb")
input_num_channels = stream.getnchannels()
input_sample_rate = stream.getframerate()
input_sample_width = stream.getsampwidth()
input_num_frames = stream.getnframes()
raw_data = stream.readframes(input_num_frames) # Returns byte data
stream.close()
total_samples = input_num_frames * input_num_channels
print "Sample Width: {} ({}-bit)".format(input_sample_width, 8 * input_sample_width)
print "Number of Channels: " + str(input_num_channels)
print "Sample Rate " + str(input_sample_rate)
print "Number of Samples: " + str(total_samples)
print "Duration: {0:.2f}s".format(total_samples / float(input_sample_rate))
print "Raw Data Size: " + str(len(raw_data))
if input_sample_rate != SAMPLE_RATE:
u_law = audioop.ratecv(raw_data, input_sample_width, input_num_channels, input_sample_rate, SAMPLE_RATE, None)
u_law = audioop.lin2ulaw(u_law[0], input_sample_width)
else:
u_law = audioop.lin2ulaw(raw_data, input_sample_width)
u_law = list(u_law)
u_law = [ord(x)//Q_FACTOR for x in u_law]
return np.asarray(u_law)
def test_lin2ulaw(self):
self.assertEqual(audioop.lin2ulaw(datas[1], 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(datas[2], 2),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
self.assertEqual(audioop.lin2ulaw(datas[4], 4),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
def test_ulaw2lin(self):
encoded = b'\x00\x0e\x28\x3f\x57\x6a\x76\x7c\x7e\x7f'\
b'\x80\x8e\xa8\xbf\xd7\xea\xf6\xfc\xfe\xff'
src = [-8031, -4447, -1471, -495, -163, -53, -18, -6, -2, 0,
8031, 4447, 1471, 495, 163, 53, 18, 6, 2, 0]
for w in 1, 2, 4:
self.assertEqual(audioop.ulaw2lin(encoded, w),
packs[w](*(x << (w * 8) >> 14 for x in src)))
# Current u-law implementation has two codes fo 0: 0x7f and 0xff.
encoded = ''.join(chr(x) for x in range(127) + range(128, 256))
for w in 2, 4:
decoded = audioop.ulaw2lin(encoded, w)
self.assertEqual(audioop.lin2ulaw(decoded, w), encoded)
def _lin2ulaw(self, data):
import audioop
return audioop.lin2ulaw(data, 2)
def writeframesraw(self, data):
if not isinstance(data, (bytes, bytearray)):
data = memoryview(data).cast('B')
self._ensure_header_written()
if self._comptype == 'ULAW':
import audioop
data = audioop.lin2ulaw(data, self._sampwidth)
nframes = len(data) // self._framesize
self._file.write(data)
self._nframeswritten = self._nframeswritten + nframes
self._datawritten = self._datawritten + len(data)
def test_lin2ulaw(self):
self.assertEqual(audioop.lin2ulaw(datas[1], 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(bytearray(datas[1]), 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(memoryview(datas[1]), 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
for w in 2, 3, 4:
self.assertEqual(audioop.lin2ulaw(datas[w], w),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
def writeframesraw(self, data):
self._ensure_header_written()
nframes = len(data) / self._framesize
if self._comptype == 'ULAW':
import audioop
data = audioop.lin2ulaw(data, self._sampwidth)
self._file.write(data)
self._nframeswritten = self._nframeswritten + nframes
self._datawritten = self._datawritten + len(data)
def test_lin2ulaw(self):
self.assertEqual(audioop.lin2ulaw(datas[1], 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(datas[2], 2),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
self.assertEqual(audioop.lin2ulaw(datas[4], 4),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
def test_ulaw2lin(self):
encoded = b'\x00\x0e\x28\x3f\x57\x6a\x76\x7c\x7e\x7f'\
b'\x80\x8e\xa8\xbf\xd7\xea\xf6\xfc\xfe\xff'
src = [-8031, -4447, -1471, -495, -163, -53, -18, -6, -2, 0,
8031, 4447, 1471, 495, 163, 53, 18, 6, 2, 0]
for w in 1, 2, 4:
self.assertEqual(audioop.ulaw2lin(encoded, w),
packs[w](*(x << (w * 8) >> 14 for x in src)))
# Current u-law implementation has two codes fo 0: 0x7f and 0xff.
encoded = ''.join(chr(x) for x in range(127) + range(128, 256))
for w in 2, 4:
decoded = audioop.ulaw2lin(encoded, w)
self.assertEqual(audioop.lin2ulaw(decoded, w), encoded)
def _lin2ulaw(self, data):
import audioop
return audioop.lin2ulaw(data, 2)
def writeframesraw(self, data):
self._ensure_header_written()
if self._comptype == 'ULAW':
import audioop
data = audioop.lin2ulaw(data, self._sampwidth)
nframes = len(data) // self._framesize
self._file.write(data)
self._nframeswritten = self._nframeswritten + nframes
self._datawritten = self._datawritten + len(data)
def _lin2ulaw(self, data):
import audioop
return audioop.lin2ulaw(data, 2)
def writeframesraw(self, data):
if not isinstance(data, (bytes, bytearray)):
data = memoryview(data).cast('B')
self._ensure_header_written()
if self._comptype == 'ULAW':
import audioop
data = audioop.lin2ulaw(data, self._sampwidth)
nframes = len(data) // self._framesize
self._file.write(data)
self._nframeswritten = self._nframeswritten + nframes
self._datawritten = self._datawritten + len(data)
def test_lin2ulaw(self):
self.assertEqual(audioop.lin2ulaw(datas[1], 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(bytearray(datas[1]), 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
self.assertEqual(audioop.lin2ulaw(memoryview(datas[1]), 1),
b'\xff\xad\x8e\x0e\x80\x00\x67')
for w in 2, 3, 4:
self.assertEqual(audioop.lin2ulaw(datas[w], w),
b'\xff\xad\x8e\x0e\x80\x00\x7e')
