def generate_audio_frame(frame_num,
input_format="s16",
layout="stereo",
sample_rate=44100,
frame_size=1024):
"""
Generate audio frame representing part of the sinusoidal wave
:param input_format: default: s16
:param layout: default: stereo
:param sample_rate: default: 44100
:param frame_size: default: 1024
:param frame_num: frame number
:return: audio frame for sinusoidal wave audio signal slice
"""
frame = AudioFrame(format=input_format, layout=layout, samples=frame_size)
frame.sample_rate = sample_rate
frame.pts = frame_num * frame_size
for i in range(len(frame.layout.channels)):
data = np.zeros(frame_size, dtype=format_dtypes[input_format])
for j in range(frame_size):
data[j] = np.sin(2 * np.pi * (frame_num + j) * (i + 1) /
float(frame_size))
frame.planes[i].update(data)
return frame
def decode(self, encoded_frame: JitterFrame) -> List[Frame]:
frame = AudioFrame(format="s16", layout="mono", samples=SAMPLES_PER_FRAME)
frame.planes[0].update(self._convert(encoded_frame.data, SAMPLE_WIDTH))
frame.pts = encoded_frame.timestamp
frame.sample_rate = SAMPLE_RATE
frame.time_base = TIME_BASE
return [frame]
async def recv(self) -> Frame:
"""
Receive the next :class:`~av.audio.frame.AudioFrame`.
The base implementation just reads silence, subclass
:class:`AudioStreamTrack` to provide a useful implementation.
"""
if self.readyState != "live":
raise MediaStreamError
sample_rate = 8000
samples = int(AUDIO_PTIME * sample_rate)
if hasattr(self, "_timestamp"):
self._timestamp += samples
wait = self._start + (self._timestamp / sample_rate) - time.time()
await asyncio.sleep(wait)
else:
self._start = time.time()
self._timestamp = 0
frame = AudioFrame(format="s16", layout="mono", samples=samples)
for p in frame.planes:
p.update(bytes(p.buffer_size))
frame.pts = self._timestamp
frame.sample_rate = sample_rate
frame.time_base = fractions.Fraction(1, sample_rate)
return frame
def test_pts_missing_time_base(self):
resampler = AudioResampler("s16", "mono", 44100)
# resample one frame
iframe = AudioFrame("s16", "stereo", 1024)
iframe.sample_rate = 48000
iframe.pts = 0
oframes = resampler.resample(iframe)
self.assertEqual(len(oframes), 1)
oframe = oframes[0]
self.assertEqual(oframe.pts, 0)
self.assertEqual(oframe.time_base, Fraction(1, 44100))
self.assertEqual(oframe.sample_rate, 44100)
# flush
oframes = resampler.resample(None)
self.assertEqual(len(oframes), 1)
oframe = oframes[0]
self.assertEqual(oframe.pts, 925)
self.assertEqual(oframe.time_base, Fraction(1, 44100))
self.assertEqual(oframe.sample_rate, 44100)
self.assertEqual(oframe.samples, 16)
def create_audio_frame(self, samples, pts, layout="mono", sample_rate=48000):
frame = AudioFrame(format="s16", layout=layout, samples=samples)
for p in frame.planes:
p.update(bytes(p.buffer_size))
frame.pts = pts
frame.sample_rate = sample_rate
frame.time_base = fractions.Fraction(1, sample_rate)
return frame
def test_mismatched_input(self):
"""
Consecutive frames must have the same layout, sample format and sample rate.
"""
resampler = AudioResampler("s16", "mono", 44100)
# resample one frame
iframe = AudioFrame("s16", "stereo", 1024)
iframe.sample_rate = 48000
resampler.resample(iframe)
# resample another frame with a sample format
iframe = AudioFrame("s16", "mono", 1024)
iframe.sample_rate = 48000
with self.assertRaises(ValueError) as cm:
resampler.resample(iframe)
self.assertEqual(str(cm.exception),
"Frame does not match AudioResampler setup.")
def generate_audio_frame():
"""Generate a blank audio frame."""
from av import AudioFrame
audio_frame = AudioFrame(format='dbl', layout='mono', samples=1024)
# audio_bytes = b''.join(b'\x00\x00\x00\x00\x00\x00\x00\x00'
# for i in range(0, 1024))
audio_bytes = b'\x00\x00\x00\x00\x00\x00\x00\x00' * 1024
audio_frame.planes[0].update(audio_bytes)
audio_frame.sample_rate = AUDIO_SAMPLE_RATE
audio_frame.time_base = Fraction(1, AUDIO_SAMPLE_RATE)
return audio_frame
def generate_audio_frame():
"""Generate a blank audio frame."""
from av import AudioFrame
audio_frame = AudioFrame(format='dbl', layout='mono', samples=1024)
# audio_bytes = b''.join(b'\x00\x00\x00\x00\x00\x00\x00\x00'
# for i in range(0, 1024))
audio_bytes = b'\x00\x00\x00\x00\x00\x00\x00\x00' * 1024
audio_frame.planes[0].update(audio_bytes)
audio_frame.sample_rate = AUDIO_SAMPLE_RATE
audio_frame.time_base = Fraction(1, AUDIO_SAMPLE_RATE)
return audio_frame
def create_audio_frame(sample_func, samples, pts, layout="mono", sample_rate=48000):
frame = AudioFrame(format="s16", layout=layout, samples=samples)
for p in frame.planes:
buf = bytearray()
for i in range(samples):
sample = int(sample_func(i) * 32767)
buf.extend(int.to_bytes(sample, 2, sys.byteorder, signed=True))
p.update(buf)
frame.pts = pts
frame.sample_rate = sample_rate
frame.time_base = fractions.Fraction(1, sample_rate)
return frame
def test_pts_missing_time_base(self):
resampler = AudioResampler('s16', 'mono', 44100)
iframe = AudioFrame('s16', 'stereo', 1024)
iframe.sample_rate = 48000
iframe.pts = 0
oframe = resampler.resample(iframe)
self.assertIs(oframe.pts, None)
self.assertIs(oframe.time_base, None)
self.assertEqual(oframe.sample_rate, 44100)
def test_pts_missing_time_base(self):
resampler = AudioResampler('s16', 'mono', 44100)
iframe = AudioFrame('s16', 'stereo', 1024)
iframe.sample_rate = 48000
iframe.pts = 0
oframe = resampler.resample(iframe)
self.assertIs(oframe.pts, None)
self.assertIs(oframe.time_base, None)
self.assertEqual(oframe.sample_rate, 44100)
def create_audio_frames(self, layout, sample_rate, count):
frames = []
timestamp = 0
samples_per_frame = int(AUDIO_PTIME * sample_rate)
for i in range(count):
frame = AudioFrame(format="s16", layout=layout, samples=samples_per_frame)
for p in frame.planes:
p.update(bytes(p.buffer_size))
frame.pts = timestamp
frame.sample_rate = sample_rate
frame.time_base = fractions.Fraction(1, sample_rate)
frames.append(frame)
timestamp += samples_per_frame
return frames
def decode(self, encoded_frame):
frame = AudioFrame(format='s16',
layout='stereo',
samples=SAMPLES_PER_FRAME)
frame.pts = encoded_frame.timestamp
frame.sample_rate = SAMPLE_RATE
frame.time_base = TIME_BASE
length = lib.opus_decode(
self.decoder, encoded_frame.data, len(encoded_frame.data),
ffi.cast('int16_t *', frame.planes[0].buffer_ptr),
SAMPLES_PER_FRAME, 0)
assert length == SAMPLES_PER_FRAME
return [frame]
def test_pts_assertion_same_rate(self):
resampler = AudioResampler("s16", "mono")
# resample one frame
iframe = AudioFrame("s16", "stereo", 1024)
iframe.sample_rate = 48000
iframe.time_base = "1/48000"
iframe.pts = 0
oframes = resampler.resample(iframe)
self.assertEqual(len(oframes), 1)
oframe = oframes[0]
self.assertEqual(oframe.pts, 0)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
self.assertEqual(oframe.samples, iframe.samples)
# resample another frame
iframe.pts = 1024
oframes = resampler.resample(iframe)
self.assertEqual(len(oframes), 1)
oframe = oframes[0]
self.assertEqual(oframe.pts, 1024)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
self.assertEqual(oframe.samples, iframe.samples)
# resample another frame with a pts gap, do not raise exception
iframe.pts = 9999
oframes = resampler.resample(iframe)
self.assertEqual(len(oframes), 1)
oframe = oframes[0]
self.assertEqual(oframe.pts, 9999)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
self.assertEqual(oframe.samples, iframe.samples)
# flush
oframes = resampler.resample(None)
self.assertEqual(len(oframes), 0)
def decode(self, encoded_frame: JitterFrame) -> List[Frame]:
frame = AudioFrame(format="s16",
layout="stereo",
samples=SAMPLES_PER_FRAME)
frame.pts = encoded_frame.timestamp
frame.sample_rate = SAMPLE_RATE
frame.time_base = TIME_BASE
length = lib.opus_decode(
self.decoder,
encoded_frame.data,
len(encoded_frame.data),
ffi.cast("int16_t *", frame.planes[0].buffer_ptr),
SAMPLES_PER_FRAME,
0,
)
assert length == SAMPLES_PER_FRAME
return [frame]
def test_pts_assertion_new_rate(self):
resampler = AudioResampler('s16', 'mono', 44100)
iframe = AudioFrame('s16', 'stereo', 1024)
iframe.sample_rate = 48000
iframe.time_base = '1/48000'
iframe.pts = 0
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, 0)
self.assertEqual(str(oframe.time_base), '1/44100')
self.assertEqual(oframe.sample_rate, 44100)
samples_out = resampler.samples_out
self.assertTrue(samples_out > 0)
iframe.pts = 1024
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, samples_out)
self.assertEqual(str(oframe.time_base), '1/44100')
self.assertEqual(oframe.sample_rate, 44100)
def test_pts_assertion_new_rate(self):
resampler = AudioResampler('s16', 'mono', 44100)
iframe = AudioFrame('s16', 'stereo', 1024)
iframe.sample_rate = 48000
iframe.time_base = '1/48000'
iframe.pts = 0
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, 0)
self.assertEqual(str(oframe.time_base), '1/44100')
self.assertEqual(oframe.sample_rate, 44100)
samples_out = resampler.samples_out
self.assertTrue(samples_out > 0)
iframe.pts = 1024
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, samples_out)
self.assertEqual(str(oframe.time_base), '1/44100')
self.assertEqual(oframe.sample_rate, 44100)
async def recv(self):
"""
Receive the next :class:`~av.audio.frame.AudioFrame`.
The base implementation just reads silence, subclass
:class:`AudioStreamTrack` to provide a useful implementation.
"""
if self.readyState != 'live':
raise MediaStreamError
sample_rate = 8000
samples = int(AUDIO_PTIME * sample_rate)
timestamp = getattr(self, '_timestamp', 0)
self._timestamp = timestamp + samples
await asyncio.sleep(AUDIO_PTIME)
frame = AudioFrame(format='s16', layout='mono', samples=samples)
for p in frame.planes:
p.update(bytes(p.buffer_size))
frame.pts = timestamp
frame.sample_rate = sample_rate
frame.time_base = fractions.Fraction(1, sample_rate)
return frame
def test_pts_assertion_same_rate(self):
resampler = AudioResampler('s16', 'mono')
iframe = AudioFrame('s16', 'stereo', 1024)
iframe.sample_rate = 48000
iframe.time_base = '1/48000'
iframe.pts = 0
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, 0)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
iframe.pts = 1024
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, 1024)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
iframe.pts = 9999
self.assertRaises(ValueError, resampler.resample, iframe)
def test_pts_assertion_same_rate(self):
resampler = AudioResampler('s16', 'mono')
iframe = AudioFrame('s16', 'stereo', 1024)
iframe.sample_rate = 48000
iframe.time_base = '1/48000'
iframe.pts = 0
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, 0)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
iframe.pts = 1024
oframe = resampler.resample(iframe)
self.assertEqual(oframe.pts, 1024)
self.assertEqual(oframe.time_base, iframe.time_base)
self.assertEqual(oframe.sample_rate, iframe.sample_rate)
iframe.pts = 9999
self.assertRaises(ValueError, resampler.resample, iframe)