biz.source_code.dsp.signal

Class EnvelopeDetector

java.lang.Object

biz.source_code.dsp.signal.EnvelopeDetector

public class EnvelopeDetector
extends Object

An envelope detector.

The input signal is filtered by a bandpass filter before the envelope is detected.

Constructor Summary

Constructors

Constructor and Description
EnvelopeDetector(int samplingRate) Constructs an envelope detector with default parameters for audio / speech.
EnvelopeDetector(int samplingRate, double attackTime, double releaseTime, IirFilter iirFilter) Constructs an envelope detector.

Method Summary

Modifier and Type	Method and Description
float[]	process(float[] in) Processes an array of input signal values and returns an array containing the envelope levels.
double	step(double inputValue) Processes one input signal value and returns the current envelope level.

Methods inherited from class java.lang.Object

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

Constructor Detail

EnvelopeDetector

public EnvelopeDetector(int samplingRate)

Constructs an envelope detector with default parameters for audio / speech.

Parameters:

samplingRate - Sampling rate in Hz.

EnvelopeDetector

public EnvelopeDetector(int samplingRate,
                        double attackTime,
                        double releaseTime,
                        IirFilter iirFilter)

Constructs an envelope detector.

Parameters:

samplingRate - Sampling rate in Hz.

attackTime - Attack time of the envelope detector in seconds (time for 1/e convergence).

releaseTime - Release time of the envelope detector in seconds (time for 1/e convergence).

iirFilter - Filter for pre-processing the signal. May be null to bypass filtering.

Method Detail

step

public double step(double inputValue)

Processes one input signal value and returns the current envelope level.

process

public float[] process(float[] in)

Processes an array of input signal values and returns an array containing the envelope levels.