org.geotools.image.palette

Class CustomPaletteBuilder

Object

CustomPaletteBuilder

public final class CustomPaletteBuilder
extends Object

This class implements the octree quantization method as it is described in the "Graphics Gems" (ISBN 0-12-286166-3, Chapter 4, pages 297-293)

Author:

Simone Giannecchini - GeoSolutions

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	CustomPaletteBuilder.ColorNode The node of color tree.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	alphaThreshold
protected int	currLevel
protected int	currSize
static int	DEFAULT_ALPHA_TH Default value for the threshold to decide whether a pixel is opaque (>=) or transparent (<).
protected int	maxLevel maximum of tree depth
protected int	maxNodes
protected int	numBands
protected int	numNodes
protected CustomPaletteBuilder.ColorNode[]	palette
protected CustomPaletteBuilder.ColorNode[]	reduceList
protected int	requiredSize
protected CustomPaletteBuilder.ColorNode	root
protected RenderedImage	src
protected ColorModel	srcColorModel
protected int	subsampleX
protected int	subsampley
protected CustomPaletteBuilder.ColorNode	transColor
protected int	transparency

Constructor Summary

Constructors

Constructor and Description
CustomPaletteBuilder(RenderedImage src)
CustomPaletteBuilder(RenderedImage src, int size, int subsx, int subsy, int alpha_th)

Method Summary

Modifier and Type	Method and Description
CustomPaletteBuilder	buildPalette()
static boolean	canCreatePalette(ImageTypeSpecifier type) Returns true if PaletteBuilder is able to create palette for given image type.
static boolean	canCreatePalette(RenderedImage image) Returns true if PaletteBuilder is able to create palette for given rendered image.
protected int	findColorIndex(CustomPaletteBuilder.ColorNode aNode, int[] rgba, int transpBand)
int	findNearestColorIndex(int[] rgba, int transparentBand)
protected int	findPaletteEntry(CustomPaletteBuilder.ColorNode aNode, int index, byte[] red, byte[] green, byte[] blue)
protected CustomPaletteBuilder.ColorNode	freeTree(CustomPaletteBuilder.ColorNode aNode)
protected int	getBranchIndex(int[] rgba, int aLevel)
IndexColorModel	getIndexColorModel()
RenderedImage	getIndexedImage()
protected CustomPaletteBuilder.ColorNode	insertNode(CustomPaletteBuilder.ColorNode aNode, int[] rgba, int aLevel)
protected void	reduceTree()

Methods inherited from class Object

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

Field Detail

DEFAULT_ALPHA_TH

public static final int DEFAULT_ALPHA_TH

Default value for the threshold to decide whether a pixel is opaque (>=) or transparent (<). Default is 1 to try to preserve antialising

See Also:

Constant Field Values

maxLevel

protected int maxLevel

maximum of tree depth

src

protected RenderedImage src

srcColorModel

protected ColorModel srcColorModel

requiredSize

protected int requiredSize

root

protected CustomPaletteBuilder.ColorNode root

numNodes

protected int numNodes

maxNodes

protected int maxNodes

currLevel

protected int currLevel

currSize

protected int currSize

reduceList

protected CustomPaletteBuilder.ColorNode[] reduceList

palette

protected CustomPaletteBuilder.ColorNode[] palette

transparency

protected int transparency

transColor

protected CustomPaletteBuilder.ColorNode transColor

subsampleX

protected int subsampleX

subsampley

protected int subsampley

numBands

protected int numBands

alphaThreshold

protected int alphaThreshold

Constructor Detail

CustomPaletteBuilder

public CustomPaletteBuilder(RenderedImage src)

CustomPaletteBuilder

public CustomPaletteBuilder(RenderedImage src,
                            int size,
                            int subsx,
                            int subsy,
                            int alpha_th)

Method Detail

canCreatePalette

public static boolean canCreatePalette(ImageTypeSpecifier type)

Returns true if PaletteBuilder is able to create palette for given image type.

Parameters:

type - an instance of ImageTypeSpecifier to be indexed.

Returns:

true if the PaletteBuilder is likely to be able to create palette for this image type.

Throws:

IllegalArgumentException - if type is null.

canCreatePalette

public static boolean canCreatePalette(RenderedImage image)

Returns true if PaletteBuilder is able to create palette for given rendered image.

Parameters:

image - an instance of RenderedImage to be indexed.

Returns:

true if the PaletteBuilder is likely to be able to create palette for this image type.

Throws:

IllegalArgumentException - if image is null.

getIndexedImage

public RenderedImage getIndexedImage()

findColorIndex

protected int findColorIndex(CustomPaletteBuilder.ColorNode aNode,
                             int[] rgba,
                             int transpBand)

buildPalette

public CustomPaletteBuilder buildPalette()

insertNode

protected CustomPaletteBuilder.ColorNode insertNode(CustomPaletteBuilder.ColorNode aNode,
                                                    int[] rgba,
                                                    int aLevel)

getIndexColorModel

public IndexColorModel getIndexColorModel()

findPaletteEntry

protected int findPaletteEntry(CustomPaletteBuilder.ColorNode aNode,
                               int index,
                               byte[] red,
                               byte[] green,
                               byte[] blue)

getBranchIndex

protected int getBranchIndex(int[] rgba,
                             int aLevel)

reduceTree

protected void reduceTree()

freeTree

protected CustomPaletteBuilder.ColorNode freeTree(CustomPaletteBuilder.ColorNode aNode)

findNearestColorIndex

public int findNearestColorIndex(int[] rgba,
                                 int transparentBand)