Package ca.cgjennings.graphics.filters

Class CompoundPixelwiseFilter

java.lang.Object

ca.cgjennings.graphics.filters.AbstractImageFilter

ca.cgjennings.graphics.filters.AbstractPixelwiseFilter

ca.cgjennings.graphics.filters.CompoundPixelwiseFilter

All Implemented Interfaces:

java.awt.image.BufferedImageOp

public final class CompoundPixelwiseFilter
extends AbstractPixelwiseFilter

A filter that can apply multiple AbstractPixelwiseFilters in sequence. Using this filter to combine multiple filters is faster than applying each filter in sequence because it avoids the overhead of unpacking and repacking the image data multiple times.

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
CompoundPixelwiseFilter()	Creates a new compound filter with an empty filter list.
CompoundPixelwiseFilter(AbstractPixelwiseFilter... filters)	Creates a new compound filter with the specified filter list.

Method Summary

Modifier and Type	Method	Description
void	appendFilter(AbstractPixelwiseFilter filter)	Appends a new filter to the current filter list, replacing the existing list.
void	filterPixels(int[] argb, int start, int end)	This method is called with a block of ARGB values to be filtered.
AbstractPixelwiseFilter	getFilter(int index)	Returns the filter at the specified index in the list of filters.
AbstractPixelwiseFilter[]	getFilters()	Returns a copy of the filter list as an array.
int	getSize()	Returns the number of filters that will be applied by this compound filter.
void	setFilters(AbstractPixelwiseFilter... filters)	Sets the filters to be applied by this compound filter.
protected float	workFactor()	Returns a factor representing the amount of work performed by this filter relative to a filter that simply copies the source image by reading and writing each pixel.

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

filter, filter, filterPixel

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

CompoundPixelwiseFilter

public CompoundPixelwiseFilter()

Creates a new compound filter with an empty filter list. If the list is not changed, this filter will have the same effect as a CloneFilter.

CompoundPixelwiseFilter

public CompoundPixelwiseFilter(AbstractPixelwiseFilter... filters)

Creates a new compound filter with the specified filter list.

Parameters:

filters - an array of filters to apply in sequence

Method Detail

getFilters

public AbstractPixelwiseFilter[] getFilters()

Returns a copy of the filter list as an array.

Returns:

the filters applied by this compound filter

setFilters

public void setFilters(AbstractPixelwiseFilter... filters)

Sets the filters to be applied by this compound filter.

Parameters:

filters - an array of filters to apply in sequence

appendFilter

public void appendFilter(AbstractPixelwiseFilter filter)

Appends a new filter to the current filter list, replacing the existing list.

Parameters:

filter - the new filter to append

getFilter

public AbstractPixelwiseFilter getFilter(int index)

Returns the filter at the specified index in the list of filters.

Parameters:

index - the index in the filter list, from 0 to getSize()-1.

Returns:

the filter at the specified index

getSize

public int getSize()

Returns the number of filters that will be applied by this compound filter.

Returns:

the number of filters in the list

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

workFactor

protected float workFactor()

Description copied from class: AbstractPixelwiseFilter

Returns a factor representing the amount of work performed by this filter relative to a filter that simply copies the source image by reading and writing each pixel. For example, a filter that implemented a 3x3 convolution might return the value 9. The work factor value helps determine when an image should be processed in parallel. (There is significant overhead involved in running a filter in parallel, so it is only worth doing if the image is relatively large or the amount of processing per pixel is relatively high.)

Note: The work factor may vary depending on the current filter settings.

Overrides:

workFactor in class AbstractPixelwiseFilter

Returns:

the approximate amount of work per pixel, relative to simply copying the pixel values