Package whistleDetector

Class WhistleDelays

java.lang.Object

whistleDetector.WhistleDelays

public class WhistleDelays
extends Object

Class containing functions to calulate the delay between a detected whistle on one channel and the signal on an adjacent channel.

Existing FFT (spectrgram) data is used during the calculation.

The correlation function is calculated for each time partition along the length of the whistle and these correlations summed to overcome the problem of aliassing.

As the correlations are caculated, the spectrum is band limited in each time partition to only include acoustic energy close to the whistle contour. In this way, it is possible to independently calculate bearings to simultaneously occurring overlapping whistles.

Author:

Doug Gillespie

Field Summary

Fields

Modifier and Type	Field	Description
static final int	INVALID_DELAY
static final int	NO_CHANNEL_DATA

Constructor Summary

Constructors

Constructor	Description
WhistleDelays()

Method Summary

Modifier and Type	Method	Description
static int	getDelay(PamDataBlock fftDataBlock, WhistleShape whistle, int delayChannel)	Calculate the delay.

Methods inherited from class java.lang.Object

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

Field Details

INVALID_DELAY

public static final int INVALID_DELAY

See Also:

• Constant Field Values

NO_CHANNEL_DATA

public static final int NO_CHANNEL_DATA

See Also:

• Constant Field Values

Constructor Details

WhistleDelays

public WhistleDelays()

Method Details

getDelay

public static int getDelay(PamDataBlock fftDataBlock,
 WhistleShape whistle,
 int delayChannel)

Calculate the delay.

The whistle knows which channel it was detected on. Tell this functin which channel to calculate the dealy to. If FFT data for that channel does not exist, then return NO_CHANNEL_DATA

Parameters:

fftDataBlock - PamDataBlock of spectrgram data

whistle - Whistle contour from the whistle detector

delayChannel - channel to measure the delay to

Returns:

delay in samples