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Buffer Regulators

Different tasks often require AudioBuffers with specified parameters to function. For example, if you want to stream audio data across a network channel it's better to collect and send bigger chunks of audio data together. Small and frequent messages can cause unwanted heavy network load.

Buffer Size Regulator​

BufferSizeRegulator takes a variable sized input buffer and provides your callback function with a fixed amount of samples. This regulator works with mono audio.

  • targetNumberOfFrames: the desired amount of frames
  • userPointer: to pass custom data along the audio stream
  • callback: callbackFunction which provides the regulated AudioBuffer and the userPointer for your process
void BufferSizeRegulatorCallback(float* buffer, void* userPointer) {
	// Your code comes here
};

BufferSizeRegulator sizeRegulator(24000, SizeRegulatorCallback, userPointer);

sizeRegulator.process(inputBuffer, inputBuffer.numberOfSamples())

Buffer Duration Regulator​

This BufferDurationRegulator class can be used to turn a variable sized audio buffer stream into a stabilized constant length audio buffer stream. This regulator manages your audio properties and adapts to changes so your callback function always gets the desired amount of audio duration.

To initialize a BufferDurationRegulator you have to set the desired duration with outputBufferMs and your process function with audioCallback.

In this case the process function takes the following arguments:

  • buffer: I/O buffer
  • inputChannels: number of channels
  • numberOfFrames: number of input frames
  • sampleRate: sample rate of the input stream
  • userPointer: custom data pointer
void BufferDurationRegulatorCallback(
    float** buffers,
    const uint inputChannels,
    const uint numberOfFrames,
    const uint sampleRate,
    void* userPointer
) {
	// Your code comes here
};

BufferDurationRegulator durationRegulator(10, DurationRegulatorCallback)

durationRegulator.process(buffer, inputChannels, numberOfFrames, sampleRate, userPointer);

Sample Rate Regulator​

SampleRateRegulator converts an audio stream with variable sample rate to a fixed sample rate buffer stream. This regulator works with mono audio.

  • targetSampleRate: sample rate of the regulated stream
  • userPointer: to pass custom data along the audio stream
  • callback: callbackFunction which provides the regulated AudioBuffer and the userPointer along the number of samples of the provided stream
void SampleRateRegulatorCallback(float* buffer, uint numberOfSamples, void* userPointer) {
	// Your code comes here
};

SampleRateRegulator sampleRateRegulator(48000, SampleRateRegulatorCallback, userPointer);

sampleRateRegulator.process(inputBuffer, inputBuffer.getNumberOfFrames(), inputBuffer.getSampleRate())