boofcv.alg.feature.detect.extract

Class NonMaxBlock

java.lang.Object

boofcv.alg.feature.detect.extract.NonMaxBlock

Direct Known Subclasses:

NonMaxBlockRelaxed, NonMaxBlockStrict

public abstract class NonMaxBlock
extends java.lang.Object

Non-maximum extractor based on the block algorithm in [1]. The worst case complexity per pixel is 4 - 4/(n+1) where n is the region size. The algorithm works by breaking up the image into a set of evenly spaced blocks with their sides touching. The local maximum is found inside a block and then the region around that maximum is examined to see if it is truly a local max.

Each block check is independent of all the others and no information is exchanged. This algorithm could be paralyzed easily and has no memory overhead.

See NonMaxSuppression for a definition of parameters not described in this document

[1] Neubeck, A. and Van Gool, L. "Efficient non-maximum suppression" ICPR 2006

Field Summary

Fields

Modifier and Type	Field and Description
protected int	border
boolean	detectsMaximum
boolean	detectsMinimum
protected boofcv.struct.QueueCorner	localMax
protected boofcv.struct.QueueCorner	localMin
protected int	radius
protected float	thresholdMax
protected float	thresholdMin

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	NonMaxBlock(boolean detectsMinimum, boolean detectsMaximum)

Method Summary

Modifier and Type	Method and Description
int	getBorder()
int	getSearchRadius()
float	getThresholdMax()
float	getThresholdMin()
void	process(boofcv.struct.image.GrayF32 intensityImage, boofcv.struct.QueueCorner localMin, boofcv.struct.QueueCorner localMax) Detects local minimums and/or maximums in the provided intensity image.
protected abstract void	searchBlock(int x0, int y0, int x1, int y1, boofcv.struct.image.GrayF32 img)
void	setBorder(int border)
void	setSearchRadius(int radius)
void	setThresholdMax(float thresholdMax)
void	setThresholdMin(float thresholdMin)

Methods inherited from class java.lang.Object

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

Field Detail

radius

protected int radius

thresholdMin

protected float thresholdMin

thresholdMax

protected float thresholdMax

border

protected int border

localMin

protected boofcv.struct.QueueCorner localMin

localMax

protected boofcv.struct.QueueCorner localMax

detectsMinimum

public boolean detectsMinimum

detectsMaximum

public boolean detectsMaximum

Constructor Detail

NonMaxBlock

protected NonMaxBlock(boolean detectsMinimum,
                      boolean detectsMaximum)

Method Detail

process

public void process(boofcv.struct.image.GrayF32 intensityImage,
                    boofcv.struct.QueueCorner localMin,
                    boofcv.struct.QueueCorner localMax)

Detects local minimums and/or maximums in the provided intensity image.

Parameters:

intensityImage - (Input) Feature intensity image.

localMin - (Output) storage for found local minimums.

localMax - (Output) storage for found local maximums.

searchBlock

protected abstract void searchBlock(int x0,
                                    int y0,
                                    int x1,
                                    int y1,
                                    boofcv.struct.image.GrayF32 img)

setSearchRadius

public void setSearchRadius(int radius)

getBorder

public int getBorder()

setBorder

public void setBorder(int border)

getSearchRadius

public int getSearchRadius()

getThresholdMin

public float getThresholdMin()

setThresholdMin

public void setThresholdMin(float thresholdMin)

getThresholdMax

public float getThresholdMax()

setThresholdMax

public void setThresholdMax(float thresholdMax)