def rec(self, duration=None, channels=1, fs=96000, frames_per_buffer=1024, dtype=np.float32):
"""Record. If dropouts or buffer underruns occur try different
values for the frames_per_buffer variable."""
_Device.rec(self, duration=duration, channels=channels, fs=fs)
self._validate(frames_per_buffer)
missing_frames = self._get_missing_frames(frames_per_buffer, int(duration*fs))
nofsamples = missing_frames+int(duration*fs)
rec = Audio(channels=channels, fs=fs, nofsamples=nofsamples, dtype=dtype)
assert len(rec)%frames_per_buffer == 0
stream = self.pa.open(format = self._data_format(rec),
channels = rec.ch,
rate = rec.fs,
frames_per_buffer = frames_per_buffer,
input_device_index = self._index_in,
input = True,
output = False,
)
try:
self._logger.info("rec: start")
counter = 0
# split the audio into chunks the size of one buffer, so we can
# iterate over the audio in chunksizes of the same size as one buffer
it_in = iter(np.split(rec.samples, len(rec)/frames_per_buffer))
try:
while True:
chunk_in = it_in.next()
raw_1d = np.fromstring(stream.read(frames_per_buffer),
dtype=rec.samples.dtype)
# because we use an iterator chunk_in is a sliding window in the rec variable
chunk_in[:] = raw_1d.reshape((frames_per_buffer, rec.ch))
counter += 1
except StopIteration:
pass
finally:
stream.stop_stream()
self._logger.debug("chunks recorded : %i" %counter)
self._logger.debug("samples recorded: %i" %(counter*frames_per_buffer))
self._logger.debug("duration : %.3f" %(counter*frames_per_buffer/rec.fs))
finally:
self._logger.debug("rec: close stream")
stream.close()
# remove the padding (empty frames) added to fill the last buffer. Trim
# at the start, since we can treat that as latency.
rec.trim(start=missing_frames, end=None)
self._logger.debug("rec: trimmed %i samples from the start" %missing_frames)
self._check_if_clipped(rec)
self._logger.info("rec: done")
return rec
def play_rec(self, x, frames_per_buffer=1024):
"""Play audio and record from input. If dropouts or buffer underruns occur
try different values for the frames_per_buffer variable."""
_Device.play_rec(self, x)
self._validate(frames_per_buffer)
missing_frames = self._get_missing_frames(frames_per_buffer, len(x))
# generate silence to fill up missing frames
pad = Audio(channels=x.ch, fs=x.fs, nofsamples=missing_frames, dtype=x.samples.dtype)
# append the missing frames to a copy of the audio to be played. We now have
# audio that can be split into complete (full) buffers
cpy = Audio(fs=x.fs, initialdata=x.samples)
cpy.concat(pad)
assert len(cpy)%frames_per_buffer == 0
rec = Audio(channels=cpy.ch, fs=cpy.fs, nofsamples=len(cpy), dtype=cpy.samples.dtype)
stream = self.pa.open(format = self._data_format(x),
channels = x.ch,
rate = x.fs,
frames_per_buffer = frames_per_buffer,
input_device_index = self._index_in,
output_device_index = self._index_out,
input = True,
output = True,
)
try:
self._logger.info("play_rec: start")
counter = 0
# split the audio into chunks the size of one buffer, so we can
# iterate over the audio in chunksizes of the same size as one buffer
it_out = iter(np.split(cpy.samples, len(cpy)/frames_per_buffer))
it_in = iter(np.split(rec.samples, len(rec)/frames_per_buffer))
try:
while True:
chunk_out = it_out.next()
chunk_in = it_in.next()
stream.write(chunk_out.tostring(), num_frames=frames_per_buffer)
raw_1d = np.fromstring(stream.read(frames_per_buffer),
dtype=rec.samples.dtype)
# because we use an iterator chunk_in is a sliding window in the rec variable
chunk_in[:] = raw_1d.reshape((frames_per_buffer, rec.ch))
counter += 1
except StopIteration:
pass
finally:
stream.stop_stream()
self._logger.debug("chunks played : %i" %counter)
self._logger.debug("samples played : %i" %(counter*frames_per_buffer))
self._logger.debug("duration : %.3f" %(counter*frames_per_buffer/x.fs))
finally:
self._logger.debug("play_rec: close stream")
stream.close()
# remove the padding (empty frames) added to fill the last buffer. Trim
# at the start, since we can treat that as latency.
rec.trim(start=missing_frames, end=None)
self._logger.debug("play_rec: trimmed %i samples from the start" %missing_frames)
self._check_if_clipped(rec)
self._logger.info("play_rec: done")
return rec