2021-04-16 23:21:06 +08:00
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# ----------------------------------------------------------------------------
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# pyglet
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# Copyright (c) 2006-2008 Alex Holkner
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2021-04-17 01:14:38 +08:00
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# Copyright (c) 2008-2021 pyglet contributors
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2021-04-16 23:21:06 +08:00
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions
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# are met:
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#
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# * Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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# * Redistributions in binary form must reproduce the above copyright
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# notice, this list of conditions and the following disclaimer in
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# the documentation and/or other materials provided with the
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# distribution.
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# * Neither the name of pyglet nor the names of its
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# contributors may be used to endorse or promote products
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# derived from this software without specific prior written
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# permission.
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#
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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# POSSIBILITY OF SUCH DAMAGE.
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# ----------------------------------------------------------------------------
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import os
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import math
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import struct
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import random
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import ctypes
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from .codecs.base import Source, AudioFormat, AudioData
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from collections import deque
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class Envelope:
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"""Base class for SynthesisSource amplitude envelopes."""
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def get_generator(self, sample_rate, duration):
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raise NotImplementedError
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class FlatEnvelope(Envelope):
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"""A flat envelope, providing basic amplitude setting.
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:Parameters:
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`amplitude` : float
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The amplitude (volume) of the wave, from 0.0 to 1.0.
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Values outside of this range will be clamped.
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"""
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def __init__(self, amplitude=0.5):
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self.amplitude = max(min(1.0, amplitude), 0)
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def get_generator(self, sample_rate, duration):
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amplitude = self.amplitude
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while True:
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yield amplitude
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class LinearDecayEnvelope(Envelope):
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"""A linearly decaying envelope.
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This envelope linearly decays the amplitude from the peak value
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to 0, over the length of the waveform.
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:Parameters:
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`peak` : float
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The Initial peak value of the envelope, from 0.0 to 1.0.
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Values outside of this range will be clamped.
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"""
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def __init__(self, peak=1.0):
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self.peak = max(min(1.0, peak), 0)
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def get_generator(self, sample_rate, duration):
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peak = self.peak
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total_bytes = int(sample_rate * duration)
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for i in range(total_bytes):
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yield (total_bytes - i) / total_bytes * peak
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class ADSREnvelope(Envelope):
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"""A four part Attack, Decay, Suspend, Release envelope.
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This is a four part ADSR envelope. The attack, decay, and release
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parameters should be provided in seconds. For example, a value of
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0.1 would be 100ms. The sustain_amplitude parameter affects the
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sustain volume. This defaults to a value of 0.5, but can be provided
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on a scale from 0.0 to 1.0.
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:Parameters:
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`attack` : float
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The attack time, in seconds.
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`decay` : float
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The decay time, in seconds.
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`release` : float
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The release time, in seconds.
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`sustain_amplitude` : float
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The sustain amplitude (volume), from 0.0 to 1.0.
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"""
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def __init__(self, attack, decay, release, sustain_amplitude=0.5):
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self.attack = attack
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self.decay = decay
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self.release = release
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self.sustain_amplitude = max(min(1.0, sustain_amplitude), 0)
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def get_generator(self, sample_rate, duration):
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sustain_amplitude = self.sustain_amplitude
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total_bytes = int(sample_rate * duration)
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attack_bytes = int(sample_rate * self.attack)
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decay_bytes = int(sample_rate * self.decay)
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release_bytes = int(sample_rate * self.release)
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sustain_bytes = total_bytes - attack_bytes - decay_bytes - release_bytes
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decay_step = (1 - sustain_amplitude) / decay_bytes
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release_step = sustain_amplitude / release_bytes
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for i in range(1, attack_bytes + 1):
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yield i / attack_bytes
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for i in range(1, decay_bytes + 1):
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yield 1 - (i * decay_step)
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for i in range(1, sustain_bytes + 1):
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yield sustain_amplitude
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for i in range(1, release_bytes + 1):
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yield sustain_amplitude - (i * release_step)
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class TremoloEnvelope(Envelope):
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"""A tremolo envelope, for modulation amplitude.
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A tremolo envelope that modulates the amplitude of the
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waveform with a sinusoidal pattern. The depth and rate
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of modulation can be specified. Depth is calculated as
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a percentage of the maximum amplitude. For example:
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a depth of 0.2 and amplitude of 0.5 will fluctuate
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the amplitude between 0.4 an 0.5.
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:Parameters:
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`depth` : float
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The amount of fluctuation, from 0.0 to 1.0.
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`rate` : float
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The fluctuation frequency, in seconds.
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`amplitude` : float
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The peak amplitude (volume), from 0.0 to 1.0.
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"""
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def __init__(self, depth, rate, amplitude=0.5):
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self.depth = max(min(1.0, depth), 0)
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self.rate = rate
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self.amplitude = max(min(1.0, amplitude), 0)
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def get_generator(self, sample_rate, duration):
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total_bytes = int(sample_rate * duration)
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period = total_bytes / duration
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max_amplitude = self.amplitude
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min_amplitude = max(0.0, (1.0 - self.depth) * self.amplitude)
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step = (math.pi * 2) / period / self.rate
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for i in range(total_bytes):
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value = math.sin(step * i)
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yield value * (max_amplitude - min_amplitude) + min_amplitude
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class SynthesisSource(Source):
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"""Base class for synthesized waveforms.
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:Parameters:
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`duration` : float
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The length, in seconds, of audio that you wish to generate.
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`sample_rate` : int
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Audio samples per second. (CD quality is 44100).
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`sample_size` : int
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The bit precision. Must be either 8 or 16.
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"""
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def __init__(self, duration, sample_rate=44800, sample_size=16, envelope=None):
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self._duration = float(duration)
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self.audio_format = AudioFormat(
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channels=1,
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sample_size=sample_size,
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sample_rate=sample_rate)
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self._offset = 0
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self._sample_rate = sample_rate
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self._sample_size = sample_size
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self._bytes_per_sample = sample_size >> 3
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self._bytes_per_second = self._bytes_per_sample * sample_rate
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self._max_offset = int(self._bytes_per_second * self._duration)
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self.envelope = envelope or FlatEnvelope(amplitude=1.0)
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self._envelope_generator = self.envelope.get_generator(sample_rate, duration)
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if self._bytes_per_sample == 2:
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self._max_offset &= 0xfffffffe
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def get_audio_data(self, num_bytes, compensation_time=0.0):
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"""Return `num_bytes` bytes of audio data."""
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num_bytes = min(num_bytes, self._max_offset - self._offset)
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if num_bytes <= 0:
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return None
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timestamp = float(self._offset) / self._bytes_per_second
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duration = float(num_bytes) / self._bytes_per_second
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data = self._generate_data(num_bytes)
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self._offset += num_bytes
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return AudioData(data, num_bytes, timestamp, duration, [])
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def _generate_data(self, num_bytes):
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"""Generate `num_bytes` bytes of data.
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Return data as ctypes array or string.
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"""
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raise NotImplementedError('abstract')
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def seek(self, timestamp):
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self._offset = int(timestamp * self._bytes_per_second)
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# Bound within duration
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self._offset = min(max(self._offset, 0), self._max_offset)
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# Align to sample
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if self._bytes_per_sample == 2:
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self._offset &= 0xfffffffe
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self._envelope_generator = self.envelope.get_generator(self._sample_rate, self._duration)
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def save(self, filename):
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"""Save the audio to disk as a standard RIFF Wave.
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A standard RIFF wave header will be added to the raw PCM
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audio data when it is saved to disk.
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:Parameters:
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`filename` : str
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The file name to save as.
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"""
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self.seek(0)
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data = self.get_audio_data(self._max_offset).get_string_data()
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header = struct.pack('<4sI8sIHHIIHH4sI',
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b"RIFF",
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len(data) + 44 - 8,
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b"WAVEfmt ",
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16, # Default for PCM
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1, # Default for PCM
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1, # Number of channels
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self._sample_rate,
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self._bytes_per_second,
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self._bytes_per_sample,
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self._sample_size,
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b"data",
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len(data))
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with open(filename, "wb") as f:
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f.write(header)
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f.write(data)
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class Silence(SynthesisSource):
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"""A silent waveform."""
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def _generate_data(self, num_bytes):
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if self._bytes_per_sample == 1:
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return b'\127' * num_bytes
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else:
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return b'\0' * num_bytes
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class WhiteNoise(SynthesisSource):
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"""A white noise, random waveform."""
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def _generate_data(self, num_bytes):
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return os.urandom(num_bytes)
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class Sine(SynthesisSource):
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"""A sinusoid (sine) waveform.
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:Parameters:
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`duration` : float
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The length, in seconds, of audio that you wish to generate.
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`frequency` : int
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The frequency, in Hz of the waveform you wish to produce.
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`sample_rate` : int
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Audio samples per second. (CD quality is 44100).
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`sample_size` : int
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The bit precision. Must be either 8 or 16.
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"""
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def __init__(self, duration, frequency=440, **kwargs):
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super(Sine, self).__init__(duration, **kwargs)
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self.frequency = frequency
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def _generate_data(self, num_bytes):
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if self._bytes_per_sample == 1:
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samples = num_bytes
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bias = 127
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amplitude = 127
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data = (ctypes.c_ubyte * samples)()
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else:
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samples = num_bytes >> 1
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bias = 0
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amplitude = 32767
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data = (ctypes.c_short * samples)()
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step = self.frequency * (math.pi * 2) / self.audio_format.sample_rate
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envelope = self._envelope_generator
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for i in range(samples):
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data[i] = int(math.sin(step * i) * amplitude * next(envelope) + bias)
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return bytes(data)
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class Triangle(SynthesisSource):
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"""A triangle waveform.
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:Parameters:
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`duration` : float
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The length, in seconds, of audio that you wish to generate.
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`frequency` : int
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The frequency, in Hz of the waveform you wish to produce.
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`sample_rate` : int
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Audio samples per second. (CD quality is 44100).
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`sample_size` : int
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The bit precision. Must be either 8 or 16.
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"""
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def __init__(self, duration, frequency=440, **kwargs):
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super(Triangle, self).__init__(duration, **kwargs)
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self.frequency = frequency
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def _generate_data(self, num_bytes):
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if self._bytes_per_sample == 1:
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samples = num_bytes
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value = 127
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maximum = 255
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minimum = 0
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data = (ctypes.c_ubyte * samples)()
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else:
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samples = num_bytes >> 1
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value = 0
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maximum = 32767
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minimum = -32768
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data = (ctypes.c_short * samples)()
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step = (maximum - minimum) * 2 * self.frequency / self.audio_format.sample_rate
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envelope = self._envelope_generator
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for i in range(samples):
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value += step
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if value > maximum:
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value = maximum - (value - maximum)
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step = -step
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if value < minimum:
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value = minimum - (value - minimum)
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step = -step
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data[i] = int(value * next(envelope))
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return bytes(data)
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class Sawtooth(SynthesisSource):
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"""A sawtooth waveform.
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:Parameters:
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`duration` : float
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The length, in seconds, of audio that you wish to generate.
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`frequency` : int
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The frequency, in Hz of the waveform you wish to produce.
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`sample_rate` : int
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Audio samples per second. (CD quality is 44100).
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`sample_size` : int
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The bit precision. Must be either 8 or 16.
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"""
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def __init__(self, duration, frequency=440, **kwargs):
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super(Sawtooth, self).__init__(duration, **kwargs)
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self.frequency = frequency
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def _generate_data(self, num_bytes):
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|
if self._bytes_per_sample == 1:
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samples = num_bytes
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value = 127
|
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|
maximum = 255
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|
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minimum = 0
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|
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data = (ctypes.c_ubyte * samples)()
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else:
|
|
|
|
samples = num_bytes >> 1
|
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|
value = 0
|
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maximum = 32767
|
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|
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minimum = -32768
|
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data = (ctypes.c_short * samples)()
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|
step = (maximum - minimum) * self.frequency / self._sample_rate
|
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|
|
envelope = self._envelope_generator
|
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|
for i in range(samples):
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|
value += step
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if value > maximum:
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|
value = minimum + (value % maximum)
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data[i] = int(value * next(envelope))
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|
|
return bytes(data)
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|
|
|
class Square(SynthesisSource):
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|
"""A square (pulse) waveform.
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|
|
|
|
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|
:Parameters:
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|
|
`duration` : float
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|
|
The length, in seconds, of audio that you wish to generate.
|
|
|
|
`frequency` : int
|
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|
|
The frequency, in Hz of the waveform you wish to produce.
|
|
|
|
`sample_rate` : int
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|
|
Audio samples per second. (CD quality is 44100).
|
|
|
|
`sample_size` : int
|
|
|
|
The bit precision. Must be either 8 or 16.
|
|
|
|
"""
|
|
|
|
def __init__(self, duration, frequency=440, **kwargs):
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|
|
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|
|
super(Square, self).__init__(duration, **kwargs)
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|
|
self.frequency = frequency
|
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|
|
|
|
|
|
def _generate_data(self, num_bytes):
|
|
|
|
if self._bytes_per_sample == 1:
|
|
|
|
samples = num_bytes
|
|
|
|
bias = 127
|
|
|
|
amplitude = 127
|
|
|
|
data = (ctypes.c_ubyte * samples)()
|
|
|
|
else:
|
|
|
|
samples = num_bytes >> 1
|
|
|
|
bias = 0
|
|
|
|
amplitude = 32767
|
|
|
|
data = (ctypes.c_short * samples)()
|
|
|
|
half_period = self.audio_format.sample_rate / self.frequency / 2
|
|
|
|
envelope = self._envelope_generator
|
|
|
|
value = 1
|
|
|
|
count = 0
|
|
|
|
for i in range(samples):
|
|
|
|
if count >= half_period:
|
|
|
|
value = -value
|
|
|
|
count %= half_period
|
|
|
|
count += 1
|
|
|
|
data[i] = int(value * amplitude * next(envelope) + bias)
|
|
|
|
return bytes(data)
|
|
|
|
|
|
|
|
|
|
|
|
class FM(SynthesisSource):
|
|
|
|
"""A simple FM waveform.
|
|
|
|
|
|
|
|
This is a simplistic frequency modulated waveform, based on the
|
|
|
|
concepts by John Chowning. Basic sine waves are used for both
|
|
|
|
frequency carrier and modulator inputs, of which the frequencies can
|
|
|
|
be provided. The modulation index, or amplitude, can also be adjusted.
|
|
|
|
|
|
|
|
:Parameters:
|
|
|
|
`duration` : float
|
|
|
|
The length, in seconds, of audio that you wish to generate.
|
|
|
|
`carrier` : int
|
|
|
|
The carrier frequency, in Hz.
|
|
|
|
`modulator` : int
|
|
|
|
The modulator frequency, in Hz.
|
|
|
|
`mod_index` : int
|
|
|
|
The modulation index.
|
|
|
|
`sample_rate` : int
|
|
|
|
Audio samples per second. (CD quality is 44100).
|
|
|
|
`sample_size` : int
|
|
|
|
The bit precision. Must be either 8 or 16.
|
|
|
|
"""
|
|
|
|
def __init__(self, duration, carrier=440, modulator=440, mod_index=1, **kwargs):
|
|
|
|
super(FM, self).__init__(duration, **kwargs)
|
|
|
|
self.carrier = carrier
|
|
|
|
self.modulator = modulator
|
|
|
|
self.mod_index = mod_index
|
|
|
|
|
|
|
|
def _generate_data(self, num_bytes):
|
|
|
|
if self._bytes_per_sample == 1:
|
|
|
|
samples = num_bytes
|
|
|
|
bias = 127
|
|
|
|
amplitude = 127
|
|
|
|
data = (ctypes.c_ubyte * samples)()
|
|
|
|
else:
|
|
|
|
samples = num_bytes >> 1
|
|
|
|
bias = 0
|
|
|
|
amplitude = 32767
|
|
|
|
data = (ctypes.c_short * samples)()
|
|
|
|
car_step = 2 * math.pi * self.carrier
|
|
|
|
mod_step = 2 * math.pi * self.modulator
|
|
|
|
mod_index = self.mod_index
|
|
|
|
sample_rate = self._sample_rate
|
|
|
|
envelope = self._envelope_generator
|
|
|
|
sin = math.sin
|
|
|
|
# FM equation: sin((2 * pi * carrier) + sin(2 * pi * modulator))
|
|
|
|
for i in range(samples):
|
|
|
|
increment = i / sample_rate
|
|
|
|
data[i] = int(sin(car_step * increment + mod_index * sin(mod_step * increment))
|
|
|
|
* amplitude * next(envelope) + bias)
|
|
|
|
return bytes(data)
|
|
|
|
|
|
|
|
|
|
|
|
class Digitar(SynthesisSource):
|
|
|
|
"""A guitar-like waveform.
|
|
|
|
|
|
|
|
A guitar-like waveform, based on the Karplus-Strong algorithm.
|
|
|
|
The sound is similar to a plucked guitar string. The resulting
|
|
|
|
sound decays over time, and so the actual length will vary
|
|
|
|
depending on the frequency. Lower frequencies require a longer
|
|
|
|
`length` parameter to prevent cutting off abruptly.
|
|
|
|
|
|
|
|
:Parameters:
|
|
|
|
`duration` : float
|
|
|
|
The length, in seconds, of audio that you wish to generate.
|
|
|
|
`frequency` : int
|
|
|
|
The frequency, in Hz of the waveform you wish to produce.
|
|
|
|
`decay` : float
|
|
|
|
The decay rate of the effect. Defaults to 0.996.
|
|
|
|
`sample_rate` : int
|
|
|
|
Audio samples per second. (CD quality is 44100).
|
|
|
|
`sample_size` : int
|
|
|
|
The bit precision. Must be either 8 or 16.
|
|
|
|
"""
|
|
|
|
def __init__(self, duration, frequency=440, decay=0.996, **kwargs):
|
|
|
|
super(Digitar, self).__init__(duration, **kwargs)
|
|
|
|
self.frequency = frequency
|
|
|
|
self.decay = decay
|
|
|
|
self.period = int(self._sample_rate / self.frequency)
|
|
|
|
|
|
|
|
def _generate_data(self, num_bytes):
|
|
|
|
if self._bytes_per_sample == 1:
|
|
|
|
samples = num_bytes
|
|
|
|
bias = 127
|
|
|
|
amplitude = 127
|
|
|
|
data = (ctypes.c_ubyte * samples)()
|
|
|
|
else:
|
|
|
|
samples = num_bytes >> 1
|
|
|
|
bias = 0
|
|
|
|
amplitude = 32767
|
|
|
|
data = (ctypes.c_short * samples)()
|
|
|
|
random.seed(10)
|
|
|
|
period = self.period
|
|
|
|
ring_buffer = deque([random.uniform(-1, 1) for _ in range(period)], maxlen=period)
|
|
|
|
decay = self.decay
|
|
|
|
for i in range(samples):
|
|
|
|
data[i] = int(ring_buffer[0] * amplitude + bias)
|
|
|
|
ring_buffer.append(decay * (ring_buffer[0] + ring_buffer[1]) / 2)
|
|
|
|
return bytes(data)
|