Package Localiser.algorithms

Class DelayGroup

java.lang.Object

Localiser.algorithms.DelayGroup

public class DelayGroup
extends Object

Functions for attempting to efficiently prep data for correlation using a variety of pre-processing methods. Input initially complex spectrum data from waveform.

Author:

Doug Gillespie

Constructor Summary

Constructors

Constructor	Description
DelayGroup()

Method Summary

Modifier and Type	Method	Description
FFTDataArray[]	getComplexCorrelatorData(double[][] waveformInput, float sampleRate, Complex[][] preallocData, DelayMeasurementParams delayParams)	Get the complex data which will go into a cross correlation function, starting with a group of waveforms.
FFTDataArray	getComplexCorrelatorData(double[] waveformInput, int fftLength, float sampleRate, Complex[] preallocData, DelayMeasurementParams delayParams)	Get the complex data which will go into a cross correlation function, starting with a waveform.
FFTDataArray	getComplexCorrelatorData(ComplexArray spectrogramInput, float sampleRate, int signalLength, int fftLength, Complex[] preallocData, DelayMeasurementParams delayParams)	Get the complex data which will go into a cross correlation function, starting with a complex spectrum.
Correlations	getCorrelations()
TimeDelayData[]	getDelays(double[][] waveformInput, float sampleRate, DelayMeasurementParams delayParams)	Calculate time delays for a set of raw waveforms
TimeDelayData[]	getDelays(double[][] waveformInput, float sampleRate, DelayMeasurementParams delayParams, double[] maxDelays)	Calculate time delays for a set of raw waveforms

Methods inherited from class java.lang.Object

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

Constructor Details

DelayGroup

public DelayGroup()

Method Details

getDelays

public TimeDelayData[] getDelays(double[][] waveformInput,
 float sampleRate,
 DelayMeasurementParams delayParams)

Calculate time delays for a set of raw waveforms

Parameters:

waveformInput - - the raw waveforms between -1 and 1

sampleRate - - the sample rate in samples per second

delayParams - - delay measurement parameters.

Returns:

time delay class with time delays and errors in seconds.

getDelays

public TimeDelayData[] getDelays(double[][] waveformInput,
 float sampleRate,
 DelayMeasurementParams delayParams,
 double[] maxDelays)

Calculate time delays for a set of raw waveforms

Parameters:

waveformInput - - the raw waveforms between -1 and 1

sampleRate - - the sample rate in samples per second

delayParams - - delay measurement parameters.

maxDelays - m- the maximum delay search range in samples. Can be used to restrict searches. Can be null

Returns:

time delay class with time delays and errors in seconds.

getComplexCorrelatorData

public FFTDataArray[] getComplexCorrelatorData(double[][] waveformInput,
 float sampleRate,
 Complex[][] preallocData,
 DelayMeasurementParams delayParams)

Get the complex data which will go into a cross correlation function, starting with a group of waveforms.

Parameters:

waveformInput - Waveform input.

sampleRate - audio sample rate (Hz)

preallocData - preallocated data - can be null and my not be used if the envelope method isn't used.

delayParams - Parameters controlling filtering, envelope extraction, etc.

Returns:

Array of Complex spectra to go into the second stage of a cross correlation function. Will have same FFT length as input data, but will only be the first half - fftLength/2 long.

getComplexCorrelatorData

public FFTDataArray getComplexCorrelatorData(double[] waveformInput,
 int fftLength,
 float sampleRate,
 Complex[] preallocData,
 DelayMeasurementParams delayParams)

Get the complex data which will go into a cross correlation function, starting with a waveform.

Parameters:

waveformInput - Waveform input.

sampleRate - audio sample rate (Hz)

preallocData - preallocated data - can be null and my not be used if the envelope method isn't used.

delayParams - Parameters controlling filtering, envelope extraction, etc.

Returns:

Complex spectrum to go into the second stage of a cross correlation function. Will have same FFT length as input data, but will only be the first half - fftLength/2 long.

getComplexCorrelatorData

public FFTDataArray getComplexCorrelatorData(ComplexArray spectrogramInput,
 float sampleRate,
 int signalLength,
 int fftLength,
 Complex[] preallocData,
 DelayMeasurementParams delayParams)

Get the complex data which will go into a cross correlation function, starting with a complex spectrum.

This can be used to save a certain amount of processing time since it minimises the number of fft and ifft's that need doing to a particular waveform.

Parameters:

spectrogramInput - Complex spectrum data. Only need the first half, so it can be fftLength or fftLength/2 long.

sampleRate - audio sample rate (Hz)

signalLength - signal length (can be invalid input: '<' fftLength)

fftLength - FFT length used to calculate the spectrum.

preallocData - preallocated data - can be null and my not be used if the envelope method isn't used.

delayParams - Parameters controlling filtering, envelope extraction, etc.

Returns:

Complex spectrum to go into the second stage of a cross correlation function. Will have same FFT length as input data, but will only be the first half - fftLength/2 long.

getCorrelations

public Correlations getCorrelations()

Returns:

the correlations