Package org.apache.commons.imaging.palette

Class PaletteFactory

java.lang.Object

org.apache.commons.imaging.palette.PaletteFactory

public class PaletteFactory
extends Object

Factory for creating palettes.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	COMPONENTS

Constructor Summary

Constructors

Constructor	Description
PaletteFactory()

Method Summary

Modifier and Type	Method	Description
int	countTransparentColors(BufferedImage src)
int	countTrasparentColors(int[] rgbs)
boolean	hasTransparency(BufferedImage src)
boolean	hasTransparency(BufferedImage src, int threshold)
boolean	isGrayscale(BufferedImage src)
Palette	makeExactRgbPaletteFancy(BufferedImage src)	Builds an exact complete opaque palette containing all the colors in src, using an algorithm that is faster than makeExactRgbPaletteSimple(java.awt.image.BufferedImage, int) for large images but uses 2 mebibytes of working memory.
SimplePalette	makeExactRgbPaletteSimple(BufferedImage src, int max)	Builds an exact complete opaque palette containing all the colors in src, and fails by returning null if there are more than max colors necessary to do this.
Palette	makeQuantizedRgbaPalette(BufferedImage src, boolean transparent, int max)	Builds an inexact possibly translucent palette of at most max colors in src using the traditional Median Cut algorithm.
Palette	makeQuantizedRgbPalette(BufferedImage src, int max)	Builds an inexact opaque palette of at most max colors in src using a variation of the Median Cut algorithm.

Methods inherited from class java.lang.Object

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

Field Details

COMPONENTS

public static final int COMPONENTS

See Also:

• Constant Field Values

Constructor Details

PaletteFactory

public PaletteFactory()

Method Details

countTransparentColors

public int countTransparentColors(BufferedImage src)

countTrasparentColors

public int countTrasparentColors(int[] rgbs)

hasTransparency

public boolean hasTransparency(BufferedImage src)

hasTransparency

public boolean hasTransparency(BufferedImage src,
 int threshold)

isGrayscale

public boolean isGrayscale(BufferedImage src)

makeExactRgbPaletteFancy

public Palette makeExactRgbPaletteFancy(BufferedImage src)

Builds an exact complete opaque palette containing all the colors in src, using an algorithm that is faster than makeExactRgbPaletteSimple(java.awt.image.BufferedImage, int) for large images but uses 2 mebibytes of working memory. Treats all the colors as opaque.

Parameters:

src - the image whose palette to build

Returns:

the palette

makeExactRgbPaletteSimple

public SimplePalette makeExactRgbPaletteSimple(BufferedImage src,
 int max)

Builds an exact complete opaque palette containing all the colors in src, and fails by returning null if there are more than max colors necessary to do this.

Parameters:

src - the image whose palette to build

max - the maximum number of colors the palette can contain

Returns:

the complete palette of max or less colors, or null if more than max colors are necessary

makeQuantizedRgbaPalette

public Palette makeQuantizedRgbaPalette(BufferedImage src,
 boolean transparent,
 int max)
                                 throws ImagingException

Builds an inexact possibly translucent palette of at most max colors in src using the traditional Median Cut algorithm. Color bounding boxes are split along the longest axis, with each step splitting the box. All bits in each component are used. The Algorithm is slower and seems exact than makeQuantizedRgbPalette(BufferedImage, int).

Parameters:

src - the image whose palette to build

transparent - whether to consider the alpha values

max - the maximum number of colors the palette can contain

Returns:

the palette of at most max colors

Throws:

ImagingException - if it fails to process the palette

makeQuantizedRgbPalette

public Palette makeQuantizedRgbPalette(BufferedImage src,
 int max)

Builds an inexact opaque palette of at most max colors in src using a variation of the Median Cut algorithm. Accurate to 6 bits per component, and works by splitting the color bounding box most heavily populated by colors along the component which splits the colors in that box most evenly.

Parameters:

src - the image whose palette to build

max - the maximum number of colors the palette can contain

Returns:

the palette of at most max colors