org.openimaj.image.analysis.algorithm.histogram

Class BinnedWindowedExtractor

java.lang.Object

org.openimaj.image.analysis.algorithm.histogram.BinnedWindowedExtractor

All Implemented Interfaces:

ImageAnalyser<FImage>, WindowedHistogramExtractor

Direct Known Subclasses:

InterpolatedBinnedWindowedExtractor

public class BinnedWindowedExtractor
extends Object
implements ImageAnalyser<FImage>, WindowedHistogramExtractor

This class implements a WindowedHistogramExtractor with the primary purpose of of producing efficient access to histograms of arbitrary windows of the image.

This class analyses an image and produces an 2D array of integers with a one-to-one correspondence with the image pixels. Each integer represents the bin of the histogram into which the corresponding pixel would fall.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Field Summary

Fields

Modifier and Type	Field and Description
protected int[][]	binMap
protected float	max
protected float	min
protected int	nbins

Constructor Summary

Constructors

Constructor and Description
BinnedWindowedExtractor(int nbins) Construct with the given number of bins.
BinnedWindowedExtractor(int nbins, float min, float max) Construct with the given number of bins, and range.

Method Summary

Methods

Modifier and Type	Method and Description
void	analyseImage(FImage image) Computes the bin-map for this image.
Histogram	computeHistogram(int x, int y, FImage weights, FImage windowWeights) Compute the histogram for the given window.
Histogram	computeHistogram(int x, int y, int w, int h) Compute the histogram for the given window.
Histogram	computeHistogram(int x, int y, int w, int h, FImage weights) Compute the histogram for the given window.
void	computeHistogram(int x, int y, int w, int h, Histogram histogram) Compute the histogram for the given window, storing the output in the given Histogram object, which must have the same length as given by WindowedHistogramExtractor.getNumBins().
Histogram	computeHistogram(Rectangle roi) Compute the histogram for the given window.
Histogram	computeHistogram(Rectangle roi, FImage weights) Compute the histogram for the given window.
void	computeHistogram(Rectangle roi, Histogram histogram) Compute the histogram for the given window, storing the output in the given Histogram object, which must have the same length as given by WindowedHistogramExtractor.getNumBins().
int[][]	getBinMap() Get the bin-map created in the last call to analyseImage(FImage) .
float	getMax() Get the expected maximum value in the input image.
float	getMin() Get the expected minimum value in the input image
int	getNumBins() Get the number of bins
void	setMax(float max) Set the expected maximum value.
void	setMin(float min) Set the expected minimum value.
void	setNbins(int nbins) Set the number of bins.

Methods inherited from class java.lang.Object

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

Field Detail

binMap

protected int[][] binMap

nbins

protected int nbins

min

protected float min

max

protected float max

Constructor Detail

BinnedWindowedExtractor

public BinnedWindowedExtractor(int nbins)

Construct with the given number of bins. The minimum expected value is assumed to be 0 and the maximum 1.

Parameters:

nbins - number of bins

BinnedWindowedExtractor

public BinnedWindowedExtractor(int nbins,
                       float min,
                       float max)

Construct with the given number of bins, and range.

Parameters:

nbins - number of bins

min - minimum expected value

max - maximum expected value

Method Detail

getNumBins

public int getNumBins()

Description copied from interface: WindowedHistogramExtractor

Get the number of bins

Specified by:

getNumBins in interface WindowedHistogramExtractor

Returns:

the number of bins

setNbins

public void setNbins(int nbins)

Set the number of bins. The new value will not take effect until analyseImage(FImage) is called.

Parameters:

nbins - the number of bins to set

getMin

public float getMin()

Get the expected minimum value in the input image

Returns:

the expected minimum value

setMin

public void setMin(float min)

Set the expected minimum value. The new value will not take effect until analyseImage(FImage) is called.

Parameters:

min - the minimum to set

getMax

public float getMax()

Get the expected maximum value in the input image.

Returns:

the expected maximum value

setMax

public void setMax(float max)

Set the expected maximum value. The new value will not take effect until analyseImage(FImage) is called.

Parameters:

max - the maximum to set

analyseImage

public void analyseImage(FImage image)

Computes the bin-map for this image.

Specified by:

analyseImage in interface ImageAnalyser<FImage>

Parameters:

image - The image to process in place.

getBinMap

public int[][] getBinMap()

Get the bin-map created in the last call to analyseImage(FImage) .

Returns:

the bin map

computeHistogram

public Histogram computeHistogram(Rectangle roi)

Description copied from interface: WindowedHistogramExtractor

Compute the histogram for the given window.

Specified by:

computeHistogram in interface WindowedHistogramExtractor

Parameters:

roi - the window

Returns:

the histogram in the window of the last analysed image

computeHistogram

public Histogram computeHistogram(int x,
                         int y,
                         int w,
                         int h)

Description copied from interface: WindowedHistogramExtractor

Compute the histogram for the given window.

Specified by:

computeHistogram in interface WindowedHistogramExtractor

Parameters:

x - The x-coordinate of the top-left of the window

y - The y-coordinate of the top-left of the window

w - The width of the window

h - The height of the window

Returns:

the histogram in the window of the last analysed image

computeHistogram

public Histogram computeHistogram(Rectangle roi,
                         FImage weights)

Compute the histogram for the given window. The weight for each bin is taken from the given weights image.

Parameters:

roi - the window

weights - the weights image. Must be the same size as the analysed image.

Returns:

the histogram in the window of the last analysed image

computeHistogram

public Histogram computeHistogram(int x,
                         int y,
                         int w,
                         int h,
                         FImage weights)

Compute the histogram for the given window. The weight for each bin is taken from the given weights image.

Parameters:

x - The x-coordinate of the top-left of the window

y - The y-coordinate of the top-left of the window

w - The width of the window

h - The height of the window

weights - the weights image. Must be the same size as the analysed image.

Returns:

the histogram in the window of the last analysed image

computeHistogram

public Histogram computeHistogram(int x,
                         int y,
                         FImage weights,
                         FImage windowWeights)

Compute the histogram for the given window. The weight for each bin is taken from the given weights image, and is multiplied by the corresponding weight in the window image before accumulation. The size of the window is taken from the window weights image.

This method primarily allows you to compute a spatially weighted histogram. For example, the window weights image could be a 2D Gaussian, and thus the histogram would apply more weight on to the centre pixels.

Parameters:

x - The x-coordinate of the top-left of the window

y - The y-coordinate of the top-left of the window

weights - The weights image. Must be the same size as the analysed image.

windowWeights - The weights for each pixel in the window.

Returns:

the histogram in the window of the last analysed image

computeHistogram

public void computeHistogram(Rectangle roi,
                    Histogram histogram)

Description copied from interface: WindowedHistogramExtractor

Compute the histogram for the given window, storing the output in the given Histogram object, which must have the same length as given by WindowedHistogramExtractor.getNumBins().

Specified by:

computeHistogram in interface WindowedHistogramExtractor

Parameters:

roi - the window

histogram - the histogram to write to

computeHistogram

public void computeHistogram(int x,
                    int y,
                    int w,
                    int h,
                    Histogram histogram)

Description copied from interface: WindowedHistogramExtractor

Compute the histogram for the given window, storing the output in the given Histogram object, which must have the same length as given by WindowedHistogramExtractor.getNumBins().

Specified by:

computeHistogram in interface WindowedHistogramExtractor

Parameters:

x - The x-coordinate of the top-left of the window

y - The y-coordinate of the top-left of the window

w - The width of the window

h - The height of the window

histogram - the histogram to write to