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Java example source code file (IndexColorModel.java)

This example Java source code file (IndexColorModel.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

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Java - Java tags/keywords

awt, biginteger, bitmask, cachesize, color, directcolormodel, illegalargumentexception, indexcolormodel, map, math, number, object, opaque, this, translucent, unsupportedoperationexception, writableraster

The IndexColorModel.java Java example source code

/*
 * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package java.awt.image;

import java.awt.Transparency;
import java.awt.color.ColorSpace;
import java.math.BigInteger;

/**
 * The <code>IndexColorModel class is a ColorModel
 * class that works with pixel values consisting of a
 * single sample that is an index into a fixed colormap in the default
 * sRGB color space.  The colormap specifies red, green, blue, and
 * optional alpha components corresponding to each index.  All components
 * are represented in the colormap as 8-bit unsigned integral values.
 * Some constructors allow the caller to specify "holes" in the colormap
 * by indicating which colormap entries are valid and which represent
 * unusable colors via the bits set in a <code>BigInteger object.
 * This color model is similar to an X11 PseudoColor visual.
 * <p>
 * Some constructors provide a means to specify an alpha component
 * for each pixel in the colormap, while others either provide no
 * such means or, in some cases, a flag to indicate whether the
 * colormap data contains alpha values.  If no alpha is supplied to
 * the constructor, an opaque alpha component (alpha = 1.0) is
 * assumed for each entry.
 * An optional transparent pixel value can be supplied that indicates a
 * pixel to be made completely transparent, regardless of any alpha
 * component supplied or assumed for that pixel value.
 * Note that the color components in the colormap of an
 * <code>IndexColorModel objects are never pre-multiplied with
 * the alpha components.
 * <p>
 * <a name="transparency">
 * The transparency of an <code>IndexColorModel object is
 * determined by examining the alpha components of the colors in the
 * colormap and choosing the most specific value after considering
 * the optional alpha values and any transparent index specified.
 * The transparency value is <code>Transparency.OPAQUE
 * only if all valid colors in
 * the colormap are opaque and there is no valid transparent pixel.
 * If all valid colors
 * in the colormap are either completely opaque (alpha = 1.0) or
 * completely transparent (alpha = 0.0), which typically occurs when
 * a valid transparent pixel is specified,
 * the value is <code>Transparency.BITMASK.
 * Otherwise, the value is <code>Transparency.TRANSLUCENT, indicating
 * that some valid color has an alpha component that is
 * neither completely transparent nor completely opaque
 * (0.0 < alpha < 1.0).
 * </a>
 *
 * <p>
 * If an <code>IndexColorModel object has
 * a transparency value of <code>Transparency.OPAQUE,
 * then the <code>hasAlpha
 * and <code>getNumComponents methods
 * (both inherited from <code>ColorModel)
 * return false and 3, respectively.
 * For any other transparency value,
 * <code>hasAlpha returns true
 * and <code>getNumComponents returns 4.
 *
 * <p>
 * <a name="index_values">
 * The values used to index into the colormap are taken from the least
 * significant <em>n bits of pixel representations where
 * <em>n is based on the pixel size specified in the constructor.
 * For pixel sizes smaller than 8 bits, <em>n is rounded up to a
 * power of two (3 becomes 4 and 5,6,7 become 8).
 * For pixel sizes between 8 and 16 bits, <em>n is equal to the
 * pixel size.
 * Pixel sizes larger than 16 bits are not supported by this class.
 * Higher order bits beyond <em>n are ignored in pixel representations.
 * Index values greater than or equal to the map size, but less than
 * 2<sup>n, are undefined and return 0 for all color and
 * alpha components.
 * </a>
 * <p>
 * For those methods that use a primitive array pixel representation of
 * type <code>transferType, the array length is always one.
 * The transfer types supported are <code>DataBuffer.TYPE_BYTE and
 * <code>DataBuffer.TYPE_USHORT.  A single int pixel
 * representation is valid for all objects of this class, since it is
 * always possible to represent pixel values used with this class in a
 * single int.  Therefore, methods that use this representation do
 * not throw an <code>IllegalArgumentException due to an invalid
 * pixel value.
 * <p>
 * Many of the methods in this class are final.  The reason for
 * this is that the underlying native graphics code makes assumptions
 * about the layout and operation of this class and those assumptions
 * are reflected in the implementations of the methods here that are
 * marked final.  You can subclass this class for other reasons, but
 * you cannot override or modify the behaviour of those methods.
 *
 * @see ColorModel
 * @see ColorSpace
 * @see DataBuffer
 *
 */
public class IndexColorModel extends ColorModel {
    private int rgb[];
    private int map_size;
    private int pixel_mask;
    private int transparent_index = -1;
    private boolean allgrayopaque;
    private BigInteger validBits;

    private sun.awt.image.BufImgSurfaceData.ICMColorData colorData = null;

    private static int[] opaqueBits = {8, 8, 8};
    private static int[] alphaBits = {8, 8, 8, 8};

    static private native void initIDs();
    static {
        ColorModel.loadLibraries();
        initIDs();
    }
    /**
     * Constructs an <code>IndexColorModel from the specified
     * arrays of red, green, and blue components.  Pixels described
     * by this color model all have alpha components of 255
     * unnormalized (1.0 normalized), which means they
     * are fully opaque.  All of the arrays specifying the color
     * components must have at least the specified number of entries.
     * The <code>ColorSpace is the default sRGB space.
     * Since there is no alpha information in any of the arguments
     * to this constructor, the transparency value is always
     * <code>Transparency.OPAQUE.
     * The transfer type is the smallest of <code>DataBuffer.TYPE_BYTE
     * or <code>DataBuffer.TYPE_USHORT that can hold a single pixel.
     * @param bits      the number of bits each pixel occupies
     * @param size      the size of the color component arrays
     * @param r         the array of red color components
     * @param g         the array of green color components
     * @param b         the array of blue color components
     * @throws IllegalArgumentException if <code>bits is less
     *         than 1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less
     *         than 1
     */
    public IndexColorModel(int bits, int size,
                           byte r[], byte g[], byte b[]) {
        super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              ColorModel.getDefaultTransferType(bits));
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        setRGBs(size, r, g, b, null);
        calculatePixelMask();
    }

    /**
     * Constructs an <code>IndexColorModel from the given arrays
     * of red, green, and blue components.  Pixels described by this color
     * model all have alpha components of 255 unnormalized
     * (1.0 normalized), which means they are fully opaque, except
     * for the indicated pixel to be made transparent.  All of the arrays
     * specifying the color components must have at least the specified
     * number of entries.
     * The <code>ColorSpace is the default sRGB space.
     * The transparency value may be <code>Transparency.OPAQUE or
     * <code>Transparency.BITMASK depending on the arguments, as
     * specified in the <a href="#transparency">class description above.
     * The transfer type is the smallest of <code>DataBuffer.TYPE_BYTE
     * or <code>DataBuffer.TYPE_USHORT that can hold a
     * single pixel.
     * @param bits      the number of bits each pixel occupies
     * @param size      the size of the color component arrays
     * @param r         the array of red color components
     * @param g         the array of green color components
     * @param b         the array of blue color components
     * @param trans     the index of the transparent pixel
     * @throws IllegalArgumentException if <code>bits is less than
     *          1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less than
     *          1
     */
    public IndexColorModel(int bits, int size,
                           byte r[], byte g[], byte b[], int trans) {
        super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              ColorModel.getDefaultTransferType(bits));
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        setRGBs(size, r, g, b, null);
        setTransparentPixel(trans);
        calculatePixelMask();
    }

    /**
     * Constructs an <code>IndexColorModel from the given
     * arrays of red, green, blue and alpha components.  All of the
     * arrays specifying the components must have at least the specified
     * number of entries.
     * The <code>ColorSpace is the default sRGB space.
     * The transparency value may be any of <code>Transparency.OPAQUE,
     * <code>Transparency.BITMASK,
     * or <code>Transparency.TRANSLUCENT
     * depending on the arguments, as specified
     * in the <a href="#transparency">class description above.
     * The transfer type is the smallest of <code>DataBuffer.TYPE_BYTE
     * or <code>DataBuffer.TYPE_USHORT that can hold a single pixel.
     * @param bits      the number of bits each pixel occupies
     * @param size      the size of the color component arrays
     * @param r         the array of red color components
     * @param g         the array of green color components
     * @param b         the array of blue color components
     * @param a         the array of alpha value components
     * @throws IllegalArgumentException if <code>bits is less
     *           than 1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less
     *           than 1
     */
    public IndexColorModel(int bits, int size,
                           byte r[], byte g[], byte b[], byte a[]) {
        super (bits, alphaBits,
               ColorSpace.getInstance(ColorSpace.CS_sRGB),
               true, false, TRANSLUCENT,
               ColorModel.getDefaultTransferType(bits));
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        setRGBs (size, r, g, b, a);
        calculatePixelMask();
    }

    /**
     * Constructs an <code>IndexColorModel from a single
     * array of interleaved red, green, blue and optional alpha
     * components.  The array must have enough values in it to
     * fill all of the needed component arrays of the specified
     * size.  The <code>ColorSpace is the default sRGB space.
     * The transparency value may be any of <code>Transparency.OPAQUE,
     * <code>Transparency.BITMASK,
     * or <code>Transparency.TRANSLUCENT
     * depending on the arguments, as specified
     * in the <a href="#transparency">class description above.
     * The transfer type is the smallest of
     * <code>DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT
     * that can hold a single pixel.
     *
     * @param bits      the number of bits each pixel occupies
     * @param size      the size of the color component arrays
     * @param cmap      the array of color components
     * @param start     the starting offset of the first color component
     * @param hasalpha  indicates whether alpha values are contained in
     *                  the <code>cmap array
     * @throws IllegalArgumentException if <code>bits is less
     *           than 1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less
     *           than 1
     */
    public IndexColorModel(int bits, int size, byte cmap[], int start,
                           boolean hasalpha) {
        this(bits, size, cmap, start, hasalpha, -1);
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
    }

    /**
     * Constructs an <code>IndexColorModel from a single array of
     * interleaved red, green, blue and optional alpha components.  The
     * specified transparent index represents a pixel that is made
     * entirely transparent regardless of any alpha value specified
     * for it.  The array must have enough values in it to fill all
     * of the needed component arrays of the specified size.
     * The <code>ColorSpace is the default sRGB space.
     * The transparency value may be any of <code>Transparency.OPAQUE,
     * <code>Transparency.BITMASK,
     * or <code>Transparency.TRANSLUCENT
     * depending on the arguments, as specified
     * in the <a href="#transparency">class description above.
     * The transfer type is the smallest of
     * <code>DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT
     * that can hold a single pixel.
     * @param bits      the number of bits each pixel occupies
     * @param size      the size of the color component arrays
     * @param cmap      the array of color components
     * @param start     the starting offset of the first color component
     * @param hasalpha  indicates whether alpha values are contained in
     *                  the <code>cmap array
     * @param trans     the index of the fully transparent pixel
     * @throws IllegalArgumentException if <code>bits is less than
     *               1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less than
     *               1
     */
    public IndexColorModel(int bits, int size, byte cmap[], int start,
                           boolean hasalpha, int trans) {
        // REMIND: This assumes the ordering: RGB[A]
        super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              ColorModel.getDefaultTransferType(bits));

        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
        map_size = size;
        rgb = new int[calcRealMapSize(bits, size)];
        int j = start;
        int alpha = 0xff;
        boolean allgray = true;
        int transparency = OPAQUE;
        for (int i = 0; i < size; i++) {
            int r = cmap[j++] & 0xff;
            int g = cmap[j++] & 0xff;
            int b = cmap[j++] & 0xff;
            allgray = allgray && (r == g) && (g == b);
            if (hasalpha) {
                alpha = cmap[j++] & 0xff;
                if (alpha != 0xff) {
                    if (alpha == 0x00) {
                        if (transparency == OPAQUE) {
                            transparency = BITMASK;
                        }
                        if (transparent_index < 0) {
                            transparent_index = i;
                        }
                    } else {
                        transparency = TRANSLUCENT;
                    }
                    allgray = false;
                }
            }
            rgb[i] = (alpha << 24) | (r << 16) | (g << 8) | b;
        }
        this.allgrayopaque = allgray;
        setTransparency(transparency);
        setTransparentPixel(trans);
        calculatePixelMask();
    }

    /**
     * Constructs an <code>IndexColorModel from an array of
     * ints where each int is comprised of red, green, blue, and
     * optional alpha components in the default RGB color model format.
     * The specified transparent index represents a pixel that is made
     * entirely transparent regardless of any alpha value specified
     * for it.  The array must have enough values in it to fill all
     * of the needed component arrays of the specified size.
     * The <code>ColorSpace is the default sRGB space.
     * The transparency value may be any of <code>Transparency.OPAQUE,
     * <code>Transparency.BITMASK,
     * or <code>Transparency.TRANSLUCENT
     * depending on the arguments, as specified
     * in the <a href="#transparency">class description above.
     * @param bits      the number of bits each pixel occupies
     * @param size      the size of the color component arrays
     * @param cmap      the array of color components
     * @param start     the starting offset of the first color component
     * @param hasalpha  indicates whether alpha values are contained in
     *                  the <code>cmap array
     * @param trans     the index of the fully transparent pixel
     * @param transferType the data type of the array used to represent
     *           pixel values.  The data type must be either
     *           <code>DataBuffer.TYPE_BYTE or
     *           <code>DataBuffer.TYPE_USHORT.
     * @throws IllegalArgumentException if <code>bits is less
     *           than 1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less
     *           than 1
     * @throws IllegalArgumentException if <code>transferType is not
     *           one of <code>DataBuffer.TYPE_BYTE or
     *           <code>DataBuffer.TYPE_USHORT
     */
    public IndexColorModel(int bits, int size,
                           int cmap[], int start,
                           boolean hasalpha, int trans, int transferType) {
        // REMIND: This assumes the ordering: RGB[A]
        super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              transferType);

        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
        if ((transferType != DataBuffer.TYPE_BYTE) &&
            (transferType != DataBuffer.TYPE_USHORT)) {
            throw new IllegalArgumentException("transferType must be either" +
                "DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT");
        }

        setRGBs(size, cmap, start, hasalpha);
        setTransparentPixel(trans);
        calculatePixelMask();
    }

    /**
     * Constructs an <code>IndexColorModel from an
     * <code>int array where each int is
     * comprised of red, green, blue, and alpha
     * components in the default RGB color model format.
     * The array must have enough values in it to fill all
     * of the needed component arrays of the specified size.
     * The <code>ColorSpace is the default sRGB space.
     * The transparency value may be any of <code>Transparency.OPAQUE,
     * <code>Transparency.BITMASK,
     * or <code>Transparency.TRANSLUCENT
     * depending on the arguments, as specified
     * in the <a href="#transparency">class description above.
     * The transfer type must be one of <code>DataBuffer.TYPE_BYTE
     * <code>DataBuffer.TYPE_USHORT.
     * The <code>BigInteger object specifies the valid/invalid pixels
     * in the <code>cmap array.  A pixel is valid if the
     * <code>BigInteger value at that index is set, and is invalid
     * if the <code>BigInteger bit  at that index is not set.
     * @param bits the number of bits each pixel occupies
     * @param size the size of the color component array
     * @param cmap the array of color components
     * @param start the starting offset of the first color component
     * @param transferType the specified data type
     * @param validBits a <code>BigInteger object.  If a bit is
     *    set in the BigInteger, the pixel at that index is valid.
     *    If a bit is not set, the pixel at that index
     *    is considered invalid.  If null, all pixels are valid.
     *    Only bits from 0 to the map size are considered.
     * @throws IllegalArgumentException if <code>bits is less
     *           than 1 or greater than 16
     * @throws IllegalArgumentException if <code>size is less
     *           than 1
     * @throws IllegalArgumentException if <code>transferType is not
     *           one of <code>DataBuffer.TYPE_BYTE or
     *           <code>DataBuffer.TYPE_USHORT
     *
     * @since 1.3
     */
    public IndexColorModel(int bits, int size, int cmap[], int start,
                           int transferType, BigInteger validBits) {
        super (bits, alphaBits,
               ColorSpace.getInstance(ColorSpace.CS_sRGB),
               true, false, TRANSLUCENT,
               transferType);

        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
        if ((transferType != DataBuffer.TYPE_BYTE) &&
            (transferType != DataBuffer.TYPE_USHORT)) {
            throw new IllegalArgumentException("transferType must be either" +
                "DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT");
        }

        if (validBits != null) {
            // Check to see if it is all valid
            for (int i=0; i < size; i++) {
                if (!validBits.testBit(i)) {
                    this.validBits = validBits;
                    break;
                }
            }
        }

        setRGBs(size, cmap, start, true);
        calculatePixelMask();
    }

    private void setRGBs(int size, byte r[], byte g[], byte b[], byte a[]) {
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
        map_size = size;
        rgb = new int[calcRealMapSize(pixel_bits, size)];
        int alpha = 0xff;
        int transparency = OPAQUE;
        boolean allgray = true;
        for (int i = 0; i < size; i++) {
            int rc = r[i] & 0xff;
            int gc = g[i] & 0xff;
            int bc = b[i] & 0xff;
            allgray = allgray && (rc == gc) && (gc == bc);
            if (a != null) {
                alpha = a[i] & 0xff;
                if (alpha != 0xff) {
                    if (alpha == 0x00) {
                        if (transparency == OPAQUE) {
                            transparency = BITMASK;
                        }
                        if (transparent_index < 0) {
                            transparent_index = i;
                        }
                    } else {
                        transparency = TRANSLUCENT;
                    }
                    allgray = false;
                }
            }
            rgb[i] = (alpha << 24) | (rc << 16) | (gc << 8) | bc;
        }
        this.allgrayopaque = allgray;
        setTransparency(transparency);
    }

    private void setRGBs(int size, int cmap[], int start, boolean hasalpha) {
        map_size = size;
        rgb = new int[calcRealMapSize(pixel_bits, size)];
        int j = start;
        int transparency = OPAQUE;
        boolean allgray = true;
        BigInteger validBits = this.validBits;
        for (int i = 0; i < size; i++, j++) {
            if (validBits != null && !validBits.testBit(i)) {
                continue;
            }
            int cmaprgb = cmap[j];
            int r = (cmaprgb >> 16) & 0xff;
            int g = (cmaprgb >>  8) & 0xff;
            int b = (cmaprgb      ) & 0xff;
            allgray = allgray && (r == g) && (g == b);
            if (hasalpha) {
                int alpha = cmaprgb >>> 24;
                if (alpha != 0xff) {
                    if (alpha == 0x00) {
                        if (transparency == OPAQUE) {
                            transparency = BITMASK;
                        }
                        if (transparent_index < 0) {
                            transparent_index = i;
                        }
                    } else {
                        transparency = TRANSLUCENT;
                    }
                    allgray = false;
                }
            } else {
                cmaprgb |= 0xff000000;
            }
            rgb[i] = cmaprgb;
        }
        this.allgrayopaque = allgray;
        setTransparency(transparency);
    }

    private int calcRealMapSize(int bits, int size) {
        int newSize = Math.max(1 << bits, size);
        return Math.max(newSize, 256);
    }

    private BigInteger getAllValid() {
        int numbytes = (map_size+7)/8;
        byte[] valid = new byte[numbytes];
        java.util.Arrays.fill(valid, (byte)0xff);
        valid[0] = (byte)(0xff >>> (numbytes*8 - map_size));

        return new BigInteger(1, valid);
    }

    /**
     * Returns the transparency.  Returns either OPAQUE, BITMASK,
     * or TRANSLUCENT
     * @return the transparency of this <code>IndexColorModel
     * @see Transparency#OPAQUE
     * @see Transparency#BITMASK
     * @see Transparency#TRANSLUCENT
     */
    public int getTransparency() {
        return transparency;
    }

    /**
     * Returns an array of the number of bits for each color/alpha component.
     * The array contains the color components in the order red, green,
     * blue, followed by the alpha component, if present.
     * @return an array containing the number of bits of each color
     *         and alpha component of this <code>IndexColorModel
     */
    public int[] getComponentSize() {
        if (nBits == null) {
            if (supportsAlpha) {
                nBits = new int[4];
                nBits[3] = 8;
            }
            else {
                nBits = new int[3];
            }
            nBits[0] = nBits[1] = nBits[2] = 8;
        }
        return nBits.clone();
    }

    /**
     * Returns the size of the color/alpha component arrays in this
     * <code>IndexColorModel.
     * @return the size of the color and alpha component arrays.
     */
    final public int getMapSize() {
        return map_size;
    }

    /**
     * Returns the index of a transparent pixel in this
     * <code>IndexColorModel or -1 if there is no pixel
     * with an alpha value of 0.  If a transparent pixel was
     * explicitly specified in one of the constructors by its
     * index, then that index will be preferred, otherwise,
     * the index of any pixel which happens to be fully transparent
     * may be returned.
     * @return the index of a transparent pixel in this
     *         <code>IndexColorModel object, or -1 if there
     *         is no such pixel
     */
    final public int getTransparentPixel() {
        return transparent_index;
    }

    /**
     * Copies the array of red color components into the specified array.
     * Only the initial entries of the array as specified by
     * {@link #getMapSize() getMapSize} are written.
     * @param r the specified array into which the elements of the
     *      array of red color components are copied
     */
    final public void getReds(byte r[]) {
        for (int i = 0; i < map_size; i++) {
            r[i] = (byte) (rgb[i] >> 16);
        }
    }

    /**
     * Copies the array of green color components into the specified array.
     * Only the initial entries of the array as specified by
     * <code>getMapSize are written.
     * @param g the specified array into which the elements of the
     *      array of green color components are copied
     */
    final public void getGreens(byte g[]) {
        for (int i = 0; i < map_size; i++) {
            g[i] = (byte) (rgb[i] >> 8);
        }
    }

    /**
     * Copies the array of blue color components into the specified array.
     * Only the initial entries of the array as specified by
     * <code>getMapSize are written.
     * @param b the specified array into which the elements of the
     *      array of blue color components are copied
     */
    final public void getBlues(byte b[]) {
        for (int i = 0; i < map_size; i++) {
            b[i] = (byte) rgb[i];
        }
    }

    /**
     * Copies the array of alpha transparency components into the
     * specified array.  Only the initial entries of the array as specified
     * by <code>getMapSize are written.
     * @param a the specified array into which the elements of the
     *      array of alpha components are copied
     */
    final public void getAlphas(byte a[]) {
        for (int i = 0; i < map_size; i++) {
            a[i] = (byte) (rgb[i] >> 24);
        }
    }

    /**
     * Converts data for each index from the color and alpha component
     * arrays to an int in the default RGB ColorModel format and copies
     * the resulting 32-bit ARGB values into the specified array.  Only
     * the initial entries of the array as specified by
     * <code>getMapSize are
     * written.
     * @param rgb the specified array into which the converted ARGB
     *        values from this array of color and alpha components
     *        are copied.
     */
    final public void getRGBs(int rgb[]) {
        System.arraycopy(this.rgb, 0, rgb, 0, map_size);
    }

    private void setTransparentPixel(int trans) {
        if (trans >= 0 && trans < map_size) {
            rgb[trans] &= 0x00ffffff;
            transparent_index = trans;
            allgrayopaque = false;
            if (this.transparency == OPAQUE) {
                setTransparency(BITMASK);
            }
        }
    }

    private void setTransparency(int transparency) {
        if (this.transparency != transparency) {
            this.transparency = transparency;
            if (transparency == OPAQUE) {
                supportsAlpha = false;
                numComponents = 3;
                nBits = opaqueBits;
            } else {
                supportsAlpha = true;
                numComponents = 4;
                nBits = alphaBits;
            }
        }
    }

    /**
     * This method is called from the constructors to set the pixel_mask
     * value, which is based on the value of pixel_bits.  The pixel_mask
     * value is used to mask off the pixel parameters for methods such
     * as getRed(), getGreen(), getBlue(), getAlpha(), and getRGB().
     */
    private final void calculatePixelMask() {
        // Note that we adjust the mask so that our masking behavior here
        // is consistent with that of our native rendering loops.
        int maskbits = pixel_bits;
        if (maskbits == 3) {
            maskbits = 4;
        } else if (maskbits > 4 && maskbits < 8) {
            maskbits = 8;
        }
        pixel_mask = (1 << maskbits) - 1;
    }

    /**
     * Returns the red color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB ColorSpace, sRGB.  The pixel value
     * is specified as an int.
     * Only the lower <em>n bits of the pixel value, as specified in the
     * <a href="#index_values">class description above, are used to
     * calculate the returned value.
     * The returned value is a non pre-multiplied value.
     * @param pixel the specified pixel
     * @return the value of the red color component for the specified pixel
     */
    final public int getRed(int pixel) {
        return (rgb[pixel & pixel_mask] >> 16) & 0xff;
    }

    /**
     * Returns the green color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB ColorSpace, sRGB.  The pixel value
     * is specified as an int.
     * Only the lower <em>n bits of the pixel value, as specified in the
     * <a href="#index_values">class description above, are used to
     * calculate the returned value.
     * The returned value is a non pre-multiplied value.
     * @param pixel the specified pixel
     * @return the value of the green color component for the specified pixel
     */
    final public int getGreen(int pixel) {
        return (rgb[pixel & pixel_mask] >> 8) & 0xff;
    }

    /**
     * Returns the blue color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB ColorSpace, sRGB.  The pixel value
     * is specified as an int.
     * Only the lower <em>n bits of the pixel value, as specified in the
     * <a href="#index_values">class description above, are used to
     * calculate the returned value.
     * The returned value is a non pre-multiplied value.
     * @param pixel the specified pixel
     * @return the value of the blue color component for the specified pixel
     */
    final public int getBlue(int pixel) {
        return rgb[pixel & pixel_mask] & 0xff;
    }

    /**
     * Returns the alpha component for the specified pixel, scaled
     * from 0 to 255.  The pixel value is specified as an int.
     * Only the lower <em>n bits of the pixel value, as specified in the
     * <a href="#index_values">class description above, are used to
     * calculate the returned value.
     * @param pixel the specified pixel
     * @return the value of the alpha component for the specified pixel
     */
    final public int getAlpha(int pixel) {
        return (rgb[pixel & pixel_mask] >> 24) & 0xff;
    }

    /**
     * Returns the color/alpha components of the pixel in the default
     * RGB color model format.  The pixel value is specified as an int.
     * Only the lower <em>n bits of the pixel value, as specified in the
     * <a href="#index_values">class description above, are used to
     * calculate the returned value.
     * The returned value is in a non pre-multiplied format.
     * @param pixel the specified pixel
     * @return the color and alpha components of the specified pixel
     * @see ColorModel#getRGBdefault
     */
    final public int getRGB(int pixel) {
        return rgb[pixel & pixel_mask];
    }

    private static final int CACHESIZE = 40;
    private int lookupcache[] = new int[CACHESIZE];

    /**
     * Returns a data element array representation of a pixel in this
     * ColorModel, given an integer pixel representation in the
     * default RGB color model.  This array can then be passed to the
     * {@link WritableRaster#setDataElements(int, int, java.lang.Object) setDataElements}
     * method of a {@link WritableRaster} object.  If the pixel variable is
     * <code>null, a new array is allocated.  If pixel
     * is not <code>null, it must be
     * a primitive array of type <code>transferType; otherwise, a
     * <code>ClassCastException is thrown.  An
     * <code>ArrayIndexOutOfBoundsException is
     * thrown if <code>pixel is not large enough to hold a pixel
     * value for this <code>ColorModel.  The pixel array is returned.
     * <p>
     * Since <code>IndexColorModel can be subclassed, subclasses
     * inherit the implementation of this method and if they don't
     * override it then they throw an exception if they use an
     * unsupported <code>transferType.
     *
     * @param rgb the integer pixel representation in the default RGB
     * color model
     * @param pixel the specified pixel
     * @return an array representation of the specified pixel in this
     *  <code>IndexColorModel.
     * @throws ClassCastException if <code>pixel
     *  is not a primitive array of type <code>transferType
     * @throws ArrayIndexOutOfBoundsException if
     *  <code>pixel is not large enough to hold a pixel value
     *  for this <code>ColorModel
     * @throws UnsupportedOperationException if <code>transferType
     *         is invalid
     * @see WritableRaster#setDataElements
     * @see SampleModel#setDataElements
     */
    public synchronized Object getDataElements(int rgb, Object pixel) {
        int red = (rgb>>16) & 0xff;
        int green = (rgb>>8) & 0xff;
        int blue  = rgb & 0xff;
        int alpha = (rgb>>>24);
        int pix = 0;

        // Note that pixels are stored at lookupcache[2*i]
        // and the rgb that was searched is stored at
        // lookupcache[2*i+1].  Also, the pixel is first
        // inverted using the unary complement operator
        // before storing in the cache so it can never be 0.
        for (int i = CACHESIZE - 2; i >= 0; i -= 2) {
            if ((pix = lookupcache[i]) == 0) {
                break;
            }
            if (rgb == lookupcache[i+1]) {
                return installpixel(pixel, ~pix);
            }
        }

        if (allgrayopaque) {
            // IndexColorModel objects are all tagged as
            // non-premultiplied so ignore the alpha value
            // of the incoming color, convert the
            // non-premultiplied color components to a
            // grayscale value and search for the closest
            // gray value in the palette.  Since all colors
            // in the palette are gray, we only need compare
            // to one of the color components for a match
            // using a simple linear distance formula.

            int minDist = 256;
            int d;
            int gray = (int) (red*77 + green*150 + blue*29 + 128)/256;

            for (int i = 0; i < map_size; i++) {
                if (this.rgb[i] == 0x0) {
                    // For allgrayopaque colormaps, entries are 0
                    // iff they are an invalid color and should be
                    // ignored during color searches.
                    continue;
                }
                d = (this.rgb[i] & 0xff) - gray;
                if (d < 0) d = -d;
                if (d < minDist) {
                    pix = i;
                    if (d == 0) {
                        break;
                    }
                    minDist = d;
                }
            }
        } else if (transparency == OPAQUE) {
            // IndexColorModel objects are all tagged as
            // non-premultiplied so ignore the alpha value
            // of the incoming color and search for closest
            // color match independently using a 3 component
            // Euclidean distance formula.
            // For opaque colormaps, palette entries are 0
            // iff they are an invalid color and should be
            // ignored during color searches.
            // As an optimization, exact color searches are
            // likely to be fairly common in opaque colormaps
            // so first we will do a quick search for an
            // exact match.

            int smallestError = Integer.MAX_VALUE;
            int lut[] = this.rgb;
            int lutrgb;
            for (int i=0; i < map_size; i++) {
                lutrgb = lut[i];
                if (lutrgb == rgb && lutrgb != 0) {
                    pix = i;
                    smallestError = 0;
                    break;
                }
            }

            if (smallestError != 0) {
                for (int i=0; i < map_size; i++) {
                    lutrgb = lut[i];
                    if (lutrgb == 0) {
                        continue;
                    }

                    int tmp = ((lutrgb >> 16) & 0xff) - red;
                    int currentError = tmp*tmp;
                    if (currentError < smallestError) {
                        tmp = ((lutrgb >> 8) & 0xff) - green;
                        currentError += tmp * tmp;
                        if (currentError < smallestError) {
                            tmp = (lutrgb & 0xff) - blue;
                            currentError += tmp * tmp;
                            if (currentError < smallestError) {
                                pix = i;
                                smallestError = currentError;
                            }
                        }
                    }
                }
            }
        } else if (alpha == 0 && transparent_index >= 0) {
            // Special case - transparent color maps to the
            // specified transparent pixel, if there is one

            pix = transparent_index;
        } else {
            // IndexColorModel objects are all tagged as
            // non-premultiplied so use non-premultiplied
            // color components in the distance calculations.
            // Look for closest match using a 4 component
            // Euclidean distance formula.

            int smallestError = Integer.MAX_VALUE;
            int lut[] = this.rgb;
            for (int i=0; i < map_size; i++) {
                int lutrgb = lut[i];
                if (lutrgb == rgb) {
                    if (validBits != null && !validBits.testBit(i)) {
                        continue;
                    }
                    pix = i;
                    break;
                }

                int tmp = ((lutrgb >> 16) & 0xff) - red;
                int currentError = tmp*tmp;
                if (currentError < smallestError) {
                    tmp = ((lutrgb >> 8) & 0xff) - green;
                    currentError += tmp * tmp;
                    if (currentError < smallestError) {
                        tmp = (lutrgb & 0xff) - blue;
                        currentError += tmp * tmp;
                        if (currentError < smallestError) {
                            tmp = (lutrgb >>> 24) - alpha;
                            currentError += tmp * tmp;
                            if (currentError < smallestError &&
                                (validBits == null || validBits.testBit(i)))
                            {
                                pix = i;
                                smallestError = currentError;
                            }
                        }
                    }
                }
            }
        }
        System.arraycopy(lookupcache, 2, lookupcache, 0, CACHESIZE - 2);
        lookupcache[CACHESIZE - 1] = rgb;
        lookupcache[CACHESIZE - 2] = ~pix;
        return installpixel(pixel, pix);
    }

    private Object installpixel(Object pixel, int pix) {
        switch (transferType) {
        case DataBuffer.TYPE_INT:
            int[] intObj;
            if (pixel == null) {
                pixel = intObj = new int[1];
            } else {
                intObj = (int[]) pixel;
            }
            intObj[0] = pix;
            break;
        case DataBuffer.TYPE_BYTE:
            byte[] byteObj;
            if (pixel == null) {
                pixel = byteObj = new byte[1];
            } else {
                byteObj = (byte[]) pixel;
            }
            byteObj[0] = (byte) pix;
            break;
        case DataBuffer.TYPE_USHORT:
            short[] shortObj;
            if (pixel == null) {
                pixel = shortObj = new short[1];
            } else {
                shortObj = (short[]) pixel;
            }
            shortObj[0] = (short) pix;
            break;
        default:
            throw new UnsupportedOperationException("This method has not been "+
                             "implemented for transferType " + transferType);
        }
        return pixel;
    }

    /**
     * Returns an array of unnormalized color/alpha components for a
     * specified pixel in this <code>ColorModel.  The pixel value
     * is specified as an int.  If the <code>components array is null,
     * a new array is allocated that contains
     * <code>offset + getNumComponents() elements.
     * The <code>components array is returned,
     * with the alpha component included
     * only if <code>hasAlpha returns true.
     * Color/alpha components are stored in the <code>components array starting
     * at <code>offset even if the array is allocated by this method.
     * An <code>ArrayIndexOutOfBoundsException
     * is thrown if  the <code>components array is not null and is
     * not large enough to hold all the color and alpha components
     * starting at <code>offset.
     * @param pixel the specified pixel
     * @param components the array to receive the color and alpha
     * components of the specified pixel
     * @param offset the offset into the <code>components array at
     * which to start storing the color and alpha components
     * @return an array containing the color and alpha components of the
     * specified pixel starting at the specified offset.
     * @see ColorModel#hasAlpha
     * @see ColorModel#getNumComponents
     */
    public int[] getComponents(int pixel, int[] components, int offset) {
        if (components == null) {
            components = new int[offset+numComponents];
        }

        // REMIND: Needs to change if different color space
        components[offset+0] = getRed(pixel);
        components[offset+1] = getGreen(pixel);
        components[offset+2] = getBlue(pixel);
        if (supportsAlpha && (components.length-offset) > 3) {
            components[offset+3] = getAlpha(pixel);
        }

        return components;
    }

    /**
     * Returns an array of unnormalized color/alpha components for
     * a specified pixel in this <code>ColorModel.  The pixel
     * value is specified by an array of data elements of type
     * <code>transferType passed in as an object reference.
     * If <code>pixel is not a primitive array of type
     * <code>transferType, a ClassCastException
     * is thrown.  An <code>ArrayIndexOutOfBoundsException
     * is thrown if <code>pixel is not large enough to hold
     * a pixel value for this <code>ColorModel.  If the
     * <code>components array is null, a new array
     * is allocated that contains
     * <code>offset + getNumComponents() elements.
     * The <code>components array is returned,
     * with the alpha component included
     * only if <code>hasAlpha returns true.
     * Color/alpha components are stored in the <code>components
     * array starting at <code>offset even if the array is
     * allocated by this method.  An
     * <code>ArrayIndexOutOfBoundsException is also
     * thrown if  the <code>components array is not
     * <code>null and is not large enough to hold all the color
     * and alpha components starting at <code>offset.
     * <p>
     * Since <code>IndexColorModel can be subclassed, subclasses
     * inherit the implementation of this method and if they don't
     * override it then they throw an exception if they use an
     * unsupported <code>transferType.
     *
     * @param pixel the specified pixel
     * @param components an array that receives the color and alpha
     * components of the specified pixel
     * @param offset the index into the <code>components array at
     * which to begin storing the color and alpha components of the
     * specified pixel
     * @return an array containing the color and alpha components of the
     * specified pixel starting at the specified offset.
     * @throws ArrayIndexOutOfBoundsException if <code>pixel
     *            is not large enough to hold a pixel value for this
     *            <code>ColorModel or if the
     *            <code>components array is not null
     *            and is not large enough to hold all the color
     *            and alpha components starting at <code>offset
     * @throws ClassCastException if <code>pixel is not a
     *            primitive array of type <code>transferType
     * @throws UnsupportedOperationException if <code>transferType
     *         is not one of the supported transfer types
     * @see ColorModel#hasAlpha
     * @see ColorModel#getNumComponents
     */
    public int[] getComponents(Object pixel, int[] components, int offset) {
        int intpixel;
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])pixel;
               intpixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])pixel;
               intpixel = sdata[0] & 0xffff;
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])pixel;
               intpixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return getComponents(intpixel, components, offset);
    }

    /**
     * Returns a pixel value represented as an int in this
     * <code>ColorModel given an array of unnormalized
     * color/alpha components.  An
     * <code>ArrayIndexOutOfBoundsException
     * is thrown if the <code>components array is not large
     * enough to hold all of the color and alpha components starting
     * at <code>offset.  Since
     * <code>ColorModel can be subclassed, subclasses inherit the
     * implementation of this method and if they don't override it then
     * they throw an exception if they use an unsupported transferType.
     * @param components an array of unnormalized color and alpha
     * components
     * @param offset the index into <code>components at which to
     * begin retrieving the color and alpha components
     * @return an <code>int pixel value in this
     * <code>ColorModel corresponding to the specified components.
     * @throws ArrayIndexOutOfBoundsException if
     *  the <code>components array is not large enough to
     *  hold all of the color and alpha components starting at
     *  <code>offset
     * @throws UnsupportedOperationException if <code>transferType
     *         is invalid
     */
    public int getDataElement(int[] components, int offset) {
        int rgb = (components[offset+0]<<16)
            | (components[offset+1]<<8) | (components[offset+2]);
        if (supportsAlpha) {
            rgb |= (components[offset+3]<<24);
        }
        else {
            rgb |= 0xff000000;
        }
        Object inData = getDataElements(rgb, null);
        int pixel;
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])inData;
               pixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])inData;
               pixel = sdata[0];
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])inData;
               pixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return pixel;
    }

    /**
     * Returns a data element array representation of a pixel in this
     * <code>ColorModel given an array of unnormalized color/alpha
     * components.  This array can then be passed to the
     * <code>setDataElements method of a WritableRaster
     * object.  An <code>ArrayIndexOutOfBoundsException is
     * thrown if the
     * <code>components array is not large enough to hold all of the
     * color and alpha components starting at <code>offset.
     * If the pixel variable is <code>null, a new array
     * is allocated.  If <code>pixel is not null,
     * it must be a primitive array of type <code>transferType;
     * otherwise, a <code>ClassCastException is thrown.
     * An <code>ArrayIndexOutOfBoundsException is thrown if pixel
     * is not large enough to hold a pixel value for this
     * <code>ColorModel.
     * <p>
     * Since <code>IndexColorModel can be subclassed, subclasses
     * inherit the implementation of this method and if they don't
     * override it then they throw an exception if they use an
     * unsupported <code>transferType
     *
     * @param components an array of unnormalized color and alpha
     * components
     * @param offset the index into <code>components at which to
     * begin retrieving color and alpha components
     * @param pixel the <code>Object representing an array of color
     * and alpha components
     * @return an <code>Object representing an array of color and
     * alpha components.
     * @throws ClassCastException if <code>pixel
     *  is not a primitive array of type <code>transferType
     * @throws ArrayIndexOutOfBoundsException if
     *  <code>pixel is not large enough to hold a pixel value
     *  for this <code>ColorModel or the components
     *  array is not large enough to hold all of the color and alpha
     *  components starting at <code>offset
     * @throws UnsupportedOperationException if <code>transferType
     *         is not one of the supported transfer types
     * @see WritableRaster#setDataElements
     * @see SampleModel#setDataElements
     */
    public Object getDataElements(int[] components, int offset, Object pixel) {
        int rgb = (components[offset+0]<<16) | (components[offset+1]<<8)
            | (components[offset+2]);
        if (supportsAlpha) {
            rgb |= (components[offset+3]<<24);
        }
        else {
            rgb &= 0xff000000;
        }
        return getDataElements(rgb, pixel);
    }

    /**
     * Creates a <code>WritableRaster with the specified width
     * and height that has a data layout (<code>SampleModel)
     * compatible with this <code>ColorModel.  This method
     * only works for color models with 16 or fewer bits per pixel.
     * <p>
     * Since <code>IndexColorModel can be subclassed, any
     * subclass that supports greater than 16 bits per pixel must
     * override this method.
     *
     * @param w the width to apply to the new <code>WritableRaster
     * @param h the height to apply to the new <code>WritableRaster
     * @return a <code>WritableRaster object with the specified
     * width and height.
     * @throws UnsupportedOperationException if the number of bits in a
     *         pixel is greater than 16
     * @see WritableRaster
     * @see SampleModel
     */
    public WritableRaster createCompatibleWritableRaster(int w, int h) {
        WritableRaster raster;

        if (pixel_bits == 1 || pixel_bits == 2 || pixel_bits == 4) {
            // TYPE_BINARY
            raster = Raster.createPackedRaster(DataBuffer.TYPE_BYTE,
                                               w, h, 1, pixel_bits, null);
        }
        else if (pixel_bits <= 8) {
            raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                  w,h,1,null);
        }
        else if (pixel_bits <= 16) {
            raster = Raster.createInterleavedRaster(DataBuffer.TYPE_USHORT,
                                                  w,h,1,null);
        }
        else {
            throw new
                UnsupportedOperationException("This method is not supported "+
                                              " for pixel bits > 16.");
        }
        return raster;
    }

    /**
      * Returns <code>true if raster is compatible
      * with this <code>ColorModel or false if it
      * is not compatible with this <code>ColorModel.
      * @param raster the {@link Raster} object to test for compatibility
      * @return <code>true if raster is compatible
      * with this <code>ColorModel; false otherwise.
      *
      */
    public boolean isCompatibleRaster(Raster raster) {

        int size = raster.getSampleModel().getSampleSize(0);
        return ((raster.getTransferType() == transferType) &&
                (raster.getNumBands() == 1) && ((1 << size) >= map_size));
    }

    /**
     * Creates a <code>SampleModel with the specified
     * width and height that has a data layout compatible with
     * this <code>ColorModel.
     * @param w the width to apply to the new <code>SampleModel
     * @param h the height to apply to the new <code>SampleModel
     * @return a <code>SampleModel object with the specified
     * width and height.
     * @throws IllegalArgumentException if <code>w or
     *         <code>h is not greater than 0
     * @see SampleModel
     */
    public SampleModel createCompatibleSampleModel(int w, int h) {
        int[] off = new int[1];
        off[0] = 0;
        if (pixel_bits == 1 || pixel_bits == 2 || pixel_bits == 4) {
            return new MultiPixelPackedSampleModel(transferType, w, h,
                                                   pixel_bits);
        }
        else {
            return new ComponentSampleModel(transferType, w, h, 1, w,
                                            off);
        }
    }

    /**
     * Checks if the specified <code>SampleModel is compatible
     * with this <code>ColorModel.  If sm is
     * <code>null, this method returns false.
     * @param sm the specified <code>SampleModel,
     *           or <code>null
     * @return <code>true if the specified SampleModel
     * is compatible with this <code>ColorModel; false
     * otherwise.
     * @see SampleModel
     */
    public boolean isCompatibleSampleModel(SampleModel sm) {
        // fix 4238629
        if (! (sm instanceof ComponentSampleModel) &&
            ! (sm instanceof MultiPixelPackedSampleModel)   ) {
            return false;
        }

        // Transfer type must be the same
        if (sm.getTransferType() != transferType) {
            return false;
        }

        if (sm.getNumBands() != 1) {
            return false;
        }

        return true;
    }

    /**
     * Returns a new <code>BufferedImage of TYPE_INT_ARGB or
     * TYPE_INT_RGB that has a <code>Raster with pixel data
     * computed by expanding the indices in the source <code>Raster
     * using the color/alpha component arrays of this <code>ColorModel.
     * Only the lower <em>n bits of each index value in the source
     * <code>Raster, as specified in the
     * <a href="#index_values">class description above, are used to
     * compute the color/alpha values in the returned image.
     * If <code>forceARGB is true, a TYPE_INT_ARGB image is
     * returned regardless of whether or not this <code>ColorModel
     * has an alpha component array or a transparent pixel.
     * @param raster the specified <code>Raster
     * @param forceARGB if <code>true, the returned
     *     <code>BufferedImage is TYPE_INT_ARGB; otherwise it is
     *     TYPE_INT_RGB
     * @return a <code>BufferedImage created with the specified
     *     <code>Raster
     * @throws IllegalArgumentException if the raster argument is not
     *           compatible with this IndexColorModel
     */
    public BufferedImage convertToIntDiscrete(Raster raster,
                                              boolean forceARGB) {
        ColorModel cm;

        if (!isCompatibleRaster(raster)) {
            throw new IllegalArgumentException("This raster is not compatible" +
                 "with this IndexColorModel.");
        }
        if (forceARGB || transparency == TRANSLUCENT) {
            cm = ColorModel.getRGBdefault();
        }
        else if (transparency == BITMASK) {
            cm = new DirectColorModel(25, 0xff0000, 0x00ff00, 0x0000ff,
                                      0x1000000);
        }
        else {
            cm = new DirectColorModel(24, 0xff0000, 0x00ff00, 0x0000ff);
        }

        int w = raster.getWidth();
        int h = raster.getHeight();
        WritableRaster discreteRaster =
                  cm.createCompatibleWritableRaster(w, h);
        Object obj = null;
        int[] data = null;

        int rX = raster.getMinX();
        int rY = raster.getMinY();

        for (int y=0; y < h; y++, rY++) {
            obj = raster.getDataElements(rX, rY, w, 1, obj);
            if (obj instanceof int[]) {
                data = (int[])obj;
            } else {
                data = DataBuffer.toIntArray(obj);
            }
            for (int x=0; x < w; x++) {
                data[x] = rgb[data[x] & pixel_mask];
            }
            discreteRaster.setDataElements(0, y, w, 1, data);
        }

        return new BufferedImage(cm, discreteRaster, false, null);
    }

    /**
     * Returns whether or not the pixel is valid.
     * @param pixel the specified pixel value
     * @return <code>true if pixel
     * is valid; <code>false otherwise.
     * @since 1.3
     */
    public boolean isValid(int pixel) {
        return ((pixel >= 0 && pixel < map_size) &&
                (validBits == null || validBits.testBit(pixel)));
    }

    /**
     * Returns whether or not all of the pixels are valid.
     * @return <code>true if all pixels are valid;
     * <code>false otherwise.
     * @since 1.3
     */
    public boolean isValid() {
        return (validBits == null);
    }

    /**
     * Returns a <code>BigInteger that indicates the valid/invalid
     * pixels in the colormap.  A bit is valid if the
     * <code>BigInteger value at that index is set, and is invalid
     * if the <code>BigInteger value at that index is not set.
     * The only valid ranges to query in the <code>BigInteger are
     * between 0 and the map size.
     * @return a <code>BigInteger indicating the valid/invalid pixels.
     * @since 1.3
     */
    public BigInteger getValidPixels() {
        if (validBits == null) {
            return getAllValid();
        }
        else {
            return validBits;
        }
    }

    /**
     * Disposes of system resources associated with this
     * <code>ColorModel once this ColorModel is no
     * longer referenced.
     */
    public void finalize() {
    }

    /**
     * Returns the <code>String representation of the contents of
     * this <code>ColorModelobject.
     * @return a <code>String representing the contents of this
     * <code>ColorModel object.
     */
    public String toString() {
       return new String("IndexColorModel: #pixelBits = "+pixel_bits
                         + " numComponents = "+numComponents
                         + " color space = "+colorSpace
                         + " transparency = "+transparency
                         + " transIndex   = "+transparent_index
                         + " has alpha = "+supportsAlpha
                         + " isAlphaPre = "+isAlphaPremultiplied
                         );
    }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java IndexColorModel.java source code file:

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