de.lmu.ifi.dbs.jfeaturelib.utils

Class IntegralImage

java.lang.Object

de.lmu.ifi.dbs.jfeaturelib.utils.IntegralImage

public class IntegralImage
extends Object

Integral images are an efficient way to retrieve the sum of pixel intensities in any rectangular region of the image.

Author:

sebp

Constructor Summary

Constructors

Constructor and Description
IntegralImage()

Method Summary

Methods

Modifier and Type	Method and Description
void	compute(ij.process.ByteProcessor ip) Constructs the integral image.
long	get(int x, int y) Get value of integral image at specified position.
long	get(Rectangle region) Returns the sum of intensities in the specified rectangle.
int	getHeight() Get the image's height.
int	getWidth() Get the image's width.

Methods inherited from class java.lang.Object

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

Constructor Detail

IntegralImage

public IntegralImage()

Method Detail

compute

public void compute(ij.process.ByteProcessor ip)

Constructs the integral image.

Parameters:

ip - ImageProcessor to use

get

public long get(int x,
       int y)

Get value of integral image at specified position. In mathematical terms, this method returns \sum_{p < x; q < y} I(p, q). Calling compute(ij.process.ByteProcessor) is required before calling this method. No sanity-check of indices x and y is performed!

Parameters:

x - x-coordinate

y - y-coordinate

Returns:

sum of intensities over rectangle from origin to point (x, y)

get

public long get(Rectangle region)

Returns the sum of intensities in the specified rectangle. Parts that lie outside of the image are treated as having zero intensity.

Parameters:

region - region of interest

Returns:

sum of intensities in specified region

getHeight

public int getHeight()

Get the image's height.

Returns:

height of the image

getWidth

public int getWidth()

Get the image's width.

Returns:

width of the image