Package ca.cgjennings.graphics.filters

Class ChannelFunctionFilter

java.lang.Object

ca.cgjennings.graphics.filters.AbstractImageFilter

ca.cgjennings.graphics.filters.AbstractPixelwiseFilter

ca.cgjennings.graphics.filters.ChannelFunctionFilter

All Implemented Interfaces:

java.awt.image.BufferedImageOp

public class ChannelFunctionFilter
extends AbstractPixelwiseFilter

A image filter that applies a function to each channel. The function takes a value between 0 and 1 for a pixel's channel value, and returns a value between 0 and 1 for the output value. The returned value is clamped to lie in the allowed range, if necessary. That is, if the function returns a value less than 0, it is clamped to 0. Likewise, if it returns a value greater than 1, it is clamped to 1.

In-place filtering: This class supports in-place filtering (the source and destination images may be the same).

Author:

Chris Jennings

Constructor Summary

Constructors

Constructor	Description
ChannelFunctionFilter()	Creates a new function filter with all channel functions set to an identity function.
ChannelFunctionFilter(Fn alpha, Fn red, Fn green, Fn blue)	Creates a new function filter with the specified channel functions.

Method Summary

Modifier and Type	Method	Description
java.awt.image.BufferedImage	filter(java.awt.image.BufferedImage src, java.awt.image.BufferedImage dest)
void	filterPixels(int[] argb, int start, int end)	This method is called with a block of ARGB values to be filtered.
Fn	getAlphaFunction()
Fn	getBlueFunction()
Fn	getGreenFunction()
Fn	getRedFunction()
void	setAlphaFunction(Fn alphaFunction)
void	setBlueFunction(Fn blueFunction)
void	setGreenFunction(Fn greenFunction)
void	setRedFunction(Fn redFunction)

Methods inherited from class ca.cgjennings.graphics.filters.AbstractPixelwiseFilter

filter, filterPixel, workFactor

Methods inherited from class ca.cgjennings.graphics.filters.AbstractImageFilter

clamp, clamp, clamp, clampBoth, createCompatibleDestImage, fA, fB, fG, fR, getARGB, getARGB, getARGBSynch, getBounds2D, getPoint2D, getRenderingHints, iA, iB, iG, iR, setARGB, setARGB, setARGBSynch

Methods inherited from class java.lang.Object

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

Constructor Detail

ChannelFunctionFilter

public ChannelFunctionFilter()

Creates a new function filter with all channel functions set to an identity function.

See Also:

Fn.IDENTITY

ChannelFunctionFilter

public ChannelFunctionFilter(Fn alpha,
                             Fn red,
                             Fn green,
                             Fn blue)

Creates a new function filter with the specified channel functions.

Parameters:

alpha - the function applied to the alpha channel

red - the function applied to the red channel

green - the function applied to the green channel

blue - the function applied to the blue channel

Method Detail

getAlphaFunction

public Fn getAlphaFunction()

setAlphaFunction

public void setAlphaFunction(Fn alphaFunction)

getRedFunction

public Fn getRedFunction()

setRedFunction

public void setRedFunction(Fn redFunction)

getGreenFunction

public Fn getGreenFunction()

setGreenFunction

public void setGreenFunction(Fn greenFunction)

getBlueFunction

public Fn getBlueFunction()

setBlueFunction

public void setBlueFunction(Fn blueFunction)

filter

public java.awt.image.BufferedImage filter(java.awt.image.BufferedImage src,
                                           java.awt.image.BufferedImage dest)

Specified by:

filter in interface java.awt.image.BufferedImageOp

Overrides:

filter in class AbstractPixelwiseFilter

filterPixels

public void filterPixels(int[] argb,
                         int start,
                         int end)

Description copied from class: AbstractPixelwiseFilter

This method is called with a block of ARGB values to be filtered. Subclasses must override this method to implement the actual filtering algorithm by replacing each pixel value in the range argb[start] ... argb[end-1] with the filtered value.

Specified by:

filterPixels in class AbstractPixelwiseFilter

Parameters:

argb - an array of pixel data to filter

start - the index of the first pixel to filter

end - the index of the last pixel to filter, plus one