be.hogent.tarsos.dsp.pitch
Class Goertzel

java.lang.Object
  be.hogent.tarsos.dsp.pitch.Goertzel

All Implemented Interfaces:

AudioProcessor

public class Goertzel
extends java.lang.Object
implements AudioProcessor

Contains an implementation of the Goertzel algorithm. It can be used to detect if one or more predefined frequencies are present in a signal. E.g. to do DTMF decoding.

Author:

Joren Six

Nested Class Summary

static interface

Goertzel.FrequenciesDetectedHandler An interface used to react on detected frequencies.

Constructor Summary

Goertzel(float audioSampleRate, int bufferSize, double[] frequencies, Goertzel.FrequenciesDetectedHandler handler)

Method Summary

boolean	process(AudioEvent audioEvent) Process the audio event.
void	processingFinished() Notify the AudioProcessor that no more data is available and processing has finished.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Goertzel

public Goertzel(float audioSampleRate,
                int bufferSize,
                double[] frequencies,
                Goertzel.FrequenciesDetectedHandler handler)

Method Detail

process

public boolean process(AudioEvent audioEvent)

Description copied from interface: AudioProcessor

Process the audio event. Do the actual signal processing on an (optionally) overlapping buffer.

Specified by:

process in interface AudioProcessor

Parameters:

audioEvent - The audio event that contains audio data.

Returns:

False if the chain needs to stop here, true otherwise. This can be used to implement e.g. a silence detector.

processingFinished

public void processingFinished()

Description copied from interface: AudioProcessor

Notify the AudioProcessor that no more data is available and processing has finished. Can be used to deallocate resources or cleanup.

Specified by:

processingFinished in interface AudioProcessor