org.apache.fop.util.bitmap

Class DitherUtil

java.lang.Object

org.apache.fop.util.bitmap.DitherUtil

public final class DitherUtil
extends Object

Utility methods for dithering.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DITHER_MATRIX_2X2 Selects a 2x2 Bayer dither matrix (5 grayscales)
static int	DITHER_MATRIX_4X4 Selects a 4x4 Bayer dither matrix (17 grayscales)
static int	DITHER_MATRIX_8X8 Selects a 8x8 Bayer dither matrix (65 grayscales)

Method Summary

Methods

Modifier and Type	Method and Description
static int[]	getBayerBasePattern(int matrix) Returns the Bayer dither base pattern for a particular matrix size.
static byte[]	getBayerDither(int matrix, Color col, boolean doubleMatrix) Returns a byte array containing the dither pattern for the given 8-bit gray value.
static byte[]	getBayerDither(int matrix, int gray255, boolean doubleMatrix) Returns a byte array containing the dither pattern for the given 8-bit gray value.

Methods inherited from class java.lang.Object

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

Field Detail

DITHER_MATRIX_2X2

public static final int DITHER_MATRIX_2X2

Selects a 2x2 Bayer dither matrix (5 grayscales)

See Also:

Constant Field Values

DITHER_MATRIX_4X4

public static final int DITHER_MATRIX_4X4

Selects a 4x4 Bayer dither matrix (17 grayscales)

See Also:

Constant Field Values

DITHER_MATRIX_8X8

public static final int DITHER_MATRIX_8X8

Selects a 8x8 Bayer dither matrix (65 grayscales)

See Also:

Constant Field Values

Method Detail

getBayerBasePattern

public static int[] getBayerBasePattern(int matrix)

Returns the Bayer dither base pattern for a particular matrix size.

Parameters:

matrix - the matrix size (DITHER_MATRIX_2X2, DITHER_MATRIX_4X4 or DITHER_MATRIX_8X8)

Returns:

the base pattern for the given size

getBayerDither

public static byte[] getBayerDither(int matrix,
                    int gray255,
                    boolean doubleMatrix)

Returns a byte array containing the dither pattern for the given 8-bit gray value.

Parameters:

matrix - the matrix size (DITHER_MATRIX_2X2, DITHER_MATRIX_4X4 or DITHER_MATRIX_8X8)

gray255 - the gray value (0-255)

doubleMatrix - true if the 4x4 matrix shall be doubled to a 8x8

Returns:

the dither pattern

getBayerDither

public static byte[] getBayerDither(int matrix,
                    Color col,
                    boolean doubleMatrix)

Returns a byte array containing the dither pattern for the given 8-bit gray value.

Parameters:

matrix - the matrix size (DITHER_MATRIX_2X2, DITHER_MATRIX_4X4 or DITHER_MATRIX_8X8)

col - the color

doubleMatrix - true if the 4x4 matrix shall be doubled to a 8x8

Returns:

the dither pattern