Package org.apache.fop.util.bitmap

Class DitherUtil

  • public final class DitherUtil
extends java.lang.Object
    Utility methods for dithering.

    • Field Summary

      Fields 
      Modifier and Type Field 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

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