Package adams.data.image

Class XScreenMaskHelper

java.lang.Object

adams.data.image.XScreenMaskHelper

public class XScreenMaskHelper
extends Object

Helper class for masking out colors (like green screening).

Version:

$Revision$

Author:

lx51 (lx51 at students dot waikato dot ac dot nz)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	XScreenMaskHelper.Color	Colors that can be masked.

Constructor Summary

Constructors

Constructor	Description
XScreenMaskHelper()

Method Summary

Modifier and Type	Method	Description
static BufferedImage	applyMask(BufferedImage image, int[][] mask, int threshold, boolean down, Logger log)	Given a previously generated mask, this uses the data to mask an image.
static void	binarizeMask(int[][] mask, int threshold, boolean down, Logger log)	Given a previously generated mask, this binarizes the mask given a threshold.
static int	determineThreshold(int[][] mask, Logger log)	Determine an optimal threshold value.
protected static int	findThreshold(int[] histogram, int limit)	Finds the threshold in the normalized histogram.
static int[][]	generateMask(BufferedImage image, XScreenMaskHelper.Color color)	Generate a color mask indicating how similar each pixel is to the selected color.

Methods inherited from class java.lang.Object

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

Constructor Detail

XScreenMaskHelper

public XScreenMaskHelper()

Method Detail

generateMask

public static int[][] generateMask(BufferedImage image,
                                   XScreenMaskHelper.Color color)

Generate a color mask indicating how similar each pixel is to the selected color. The mask is normalized to 0 and 255, with 0 being not similar and 255 being very similar.

Parameters:

image - image to be processed

color - color to apply mask

Returns:

a normalized mask between 0 and 255

applyMask

public static BufferedImage applyMask(BufferedImage image,
                                      int[][] mask,
                                      int threshold,
                                      boolean down,
                                      Logger log)

Given a previously generated mask, this uses the data to mask an image.

Parameters:

image - image to mask

mask - generated mask

threshold - threshold to binarize image, specify a negative value to automatically determine a threshold

down - if true, then pixels <= threshold are not masked and the others' alpha channel are set to 0 (made transparent)

log - logger to be used to log the automatically determined threshold, can be null

Returns:

masked image, type ARGB

binarizeMask

public static void binarizeMask(int[][] mask,
                                int threshold,
                                boolean down,
                                Logger log)

Given a previously generated mask, this binarizes the mask given a threshold.

Parameters:

mask - generated mask

threshold - threshold to binarize image, specify a negative value to automatically determine a threshold

down - if true, then pixels <= threshold are not masked and the others' alpha channel are set to 0 (made transparent)

log - logger to be used to log the automatically determined threshold, can be null

findThreshold

protected static int findThreshold(int[] histogram,
                                   int limit)

Finds the threshold in the normalized histogram.

Parameters:

histogram - the histogram to process

limit - the limit to use

Returns:

the index in the histogram

determineThreshold

public static int determineThreshold(int[][] mask,
                                     Logger log)

Determine an optimal threshold value. A normalized histogram is calculated, assuming two peaks, the threshold begins in the middle, walking right until it hits the right peak, or left until it is walks off the peak.

Parameters:

mask - generated mask

log - logger to be used to log the automatically determined threshold, can be null

Returns:

threshold value