bufferedimage.java

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/*
 * @(#)BufferedImage.java	1.89 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.awt.image;

import java.awt.Transparency;
import java.awt.color.ColorSpace;
import java.awt.Graphics2D;
import java.awt.GraphicsEnvironment;
import java.awt.geom.Rectangle2D;
import java.awt.geom.Point2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.util.Hashtable;
import java.util.Vector;

import sun.awt.image.BytePackedRaster;
import sun.awt.image.ShortComponentRaster;
import sun.awt.image.ByteComponentRaster;
import sun.awt.image.IntegerComponentRaster;
import sun.awt.image.OffScreenImageSource;

/**
 *
 * The <code>BufferedImage</code> subclass describes an {@link
 * java.awt.Image Image} with an accessible buffer of image data.
 * A <code>BufferedImage</code> is comprised of a {@link ColorModel} and a
 * {@link Raster} of image data.
 * The number and types of bands in the {@link SampleModel} of the
 * <code>Raster</code> must match the number and types required by the
 * <code>ColorModel</code> to represent its color and alpha components.
 * All <code>BufferedImage</code> objects have an upper left corner
 * coordinate of (0,&nbsp;0).  Any <code>Raster</code> used to construct a
 * <code>BufferedImage</code> must therefore have minX=0 and minY=0. 
 * @see ColorModel
 * @see Raster
 * @see WritableRaster
 * @version 10 Feb 1997
 */

public class BufferedImage extends java.awt.Image
                           implements WritableRenderedImage
{
    int        imageType = TYPE_CUSTOM;
    ColorModel colorModel;
    WritableRaster raster;
    OffScreenImageSource osis;
    Hashtable properties;

    boolean    isAlphaPremultiplied;// If true, alpha has been premultiplied in
    // color channels

    sun.java2d.SurfaceData sData;

    /**
     * Image Type Constants
     */

    /**
     * Image type is not recognized so it must be a customized
     * image.  This type is only used as a return value for the getType()
     * method.
     */
    public static final int TYPE_CUSTOM = 0;

    /**
     * Represents an image with 8-bit RGB color components packed into
     * integer pixels.  The image has a {@link DirectColorModel} without
     * alpha.
     */
    public static final int TYPE_INT_RGB = 1;

    /**
     * Represents an image with 8-bit RGBA color components packed into
     * integer pixels.  The image has a <code>DirectColorModel</code> 
     * with alpha. The color data in this image is considered not to be
     * premultiplied with alpha.  When this type is used as the 
     * <code>imageType</code> argument to a <code>BufferedImage</code>
     * constructor, the created image is consistent with images
     * created in the JDK1.1 and earlier releases.
     */
    public static final int TYPE_INT_ARGB = 2;

    /**
     * Represents an image with 8-bit RGBA color components packed into
     * integer pixels.  The image has a <code>DirectColorModel</code> 
     * with alpha.  The color data in this image is considered to be
     * premultiplied with alpha.
     */
    public static final int TYPE_INT_ARGB_PRE = 3;

    /**
     * Represents an image with 8-bit RGB color components, corresponding 
     * to a Windows- or Solaris- style BGR color model, with the colors
     * Blue, Green, and Red packed into integer pixels.  There is no alpha.
     * The image has a {@link DirectColorModel}.
     */
    public static final int TYPE_INT_BGR = 4;

    /**
     * Represents an image with 8-bit RGB color components, corresponding 
     * to a Windows-style BGR color model) with the colors Blue, Green,
     * and Red stored in 3 bytes.  There is no alpha.  The image has a
     * <code>ComponentColorModel</code>.
     */
    public static final int TYPE_3BYTE_BGR = 5;

    /**
     * Represents an image with 8-bit RGBA color components with the colors
     * Blue, Green, and Red stored in 3 bytes and 1 byte of alpha.  The
     * image has a <code>ComponentColorModel</code> with alpha.  The
     * color data in this image is considered not to be premultiplied with
     * alpha.  The byte data is interleaved in a single 
     * byte array in the order A, B, G, R
     * from lower to higher byte addresses within each pixel.
     */
    public static final int TYPE_4BYTE_ABGR = 6;

    /**
     * Represents an image with 8-bit RGBA color components with the colors
     * Blue, Green, and Red stored in 3 bytes and 1 byte of alpha.  The
     * image has a <code>ComponentColorModel</code> with alpha. The color
     * data in this image is considered to be premultiplied with alpha.
     * The byte data is interleaved in a single byte array in the order
     * A, B, G, R from lower to higher byte addresses within each pixel.
     */
    public static final int TYPE_4BYTE_ABGR_PRE = 7;

    /**
     * Represents an image with 5-6-5 RGB color components (5-bits red,
     * 6-bits green, 5-bits blue) with no alpha.  This image has
     * a <code>DirectColorModel</code>.
     */
    public static final int TYPE_USHORT_565_RGB = 8;
    
    /**
     * Represents an image with 5-5-5 RGB color components (5-bits red,
     * 5-bits green, 5-bits blue) with no alpha.  This image has
     * a <code>DirectColorModel</code>.
     */
    public static final int TYPE_USHORT_555_RGB = 9;

    /**
     * Represents a unsigned byte grayscale image, non-indexed.  This
     * image has a <code>ComponentColorModel</code> with a CS_GRAY
     * {@link ColorSpace}.
     */
    public static final int TYPE_BYTE_GRAY = 10;
    
    /**
     * Represents an unsigned short grayscale image, non-indexed).  This
     * image has a <code>ComponentColorModel</code> with a CS_GRAY
     * <code>ColorSpace</code>.
     */
    public static final int TYPE_USHORT_GRAY = 11;
    
    /**
     * Represents an opaque byte-packed 1, 2, or 4 bit image.  The
     * image has an {@link IndexColorModel} without alpha.  When this
     * type is used as the <code>imageType</code> argument to the
     * <code>BufferedImage</code> constructor that takes an
     * <code>imageType</code> argument but no <code>ColorModel</code>
     * argument, a 1-bit image is created with an
     * <code>IndexColorModel</code> with two colors in the default
     * sRGB <code>ColorSpace</code>: {0,&nbsp;0,&nbsp;0} and
     * {255,&nbsp;255,&nbsp;255}.
     *
     * <p> Images with 2 or 4 bits per pixel may be constructed via
     * the <code>BufferedImage</code> constructor that takes a
     * <code>ColorModel</code> argument by supplying a
     * <code>ColorModel</code> with an appropriate map size.
     *
     * <p> Images with 8 bits per pixel should use the image types
     * <code>TYPE_BYTE_INDEXED</code> or <code>TYPE_BYTE_GRAY</code>
     * depending on their <code>ColorModel</code>.
     */
    public static final int TYPE_BYTE_BINARY = 12;

    /**
     * Represents an indexed byte image.  When this type is used as the
     * <code>imageType</code> argument to the <code>BufferedImage</code>
     * constructor that takes an <code>imageType</code> argument
     * but no <code>ColorModel</code> argument, an 
     * <code>IndexColorModel</code> is created with
     * a 256-color 6/6/6 color cube palette with the rest of the colors
     * from 216-255 populated by grayscale values in the
     * default sRGB ColorSpace.
     */
    public static final int TYPE_BYTE_INDEXED = 13;
    
    private static final int DCM_RED_MASK   = 0x00ff0000;
    private static final int DCM_GREEN_MASK = 0x0000ff00;
    private static final int DCM_BLUE_MASK  = 0x000000ff;
    private static final int DCM_ALPHA_MASK = 0xff000000;
    private static final int DCM_565_RED_MASK = 0xf800;
    private static final int DCM_565_GRN_MASK = 0x07E0;
    private static final int DCM_565_BLU_MASK = 0x001F;
    private static final int DCM_555_RED_MASK = 0x7C00;
    private static final int DCM_555_GRN_MASK = 0x03E0;
    private static final int DCM_555_BLU_MASK = 0x001F;
    private static final int DCM_BGR_RED_MASK = 0x0000ff;
    private static final int DCM_BGR_GRN_MASK = 0x00ff00;
    private static final int DCM_BGR_BLU_MASK = 0xff0000;

    
    static private native void initIDs();
    static {
        ColorModel.loadLibraries();
        initIDs();
    }

    /**
     * Constructs a <code>BufferedImage</code> of one of the predefined
     * image types.  The <code>ColorSpace</code> for the image is the
     * default sRGB space.
     * @param width     width of the created image
     * @param height    height of the created image
     * @param imageType type of the created image
     * @see ColorSpace
     * @see #TYPE_INT_RGB
     * @see #TYPE_INT_ARGB
     * @see #TYPE_INT_ARGB_PRE
     * @see #TYPE_INT_BGR
     * @see #TYPE_3BYTE_BGR
     * @see #TYPE_4BYTE_ABGR
     * @see #TYPE_4BYTE_ABGR_PRE
     * @see #TYPE_BYTE_GRAY
     * @see #TYPE_USHORT_GRAY
     * @see #TYPE_BYTE_BINARY
     * @see #TYPE_BYTE_INDEXED
     * @see #TYPE_USHORT_565_RGB
     * @see #TYPE_USHORT_555_RGB
     */
    public BufferedImage(int width, 
                         int height, 
                         int imageType) {
        switch (imageType) {
        case TYPE_INT_RGB:
            {
                colorModel = new DirectColorModel(24,
                                                  0x00ff0000,	// Red
                                                  0x0000ff00,	// Green
                                                  0x000000ff,	// Blue
                                                  0x0           // Alpha
                                                  );
                  raster = colorModel.createCompatibleWritableRaster(width,
                                                                      height);
            }
        break;
            
        case TYPE_INT_ARGB:
            {
                colorModel = ColorModel.getRGBdefault();
                
                raster = colorModel.createCompatibleWritableRaster(width,
                                                                   height);
            }
        break;

        case TYPE_INT_ARGB_PRE:
            {
                colorModel = new
                    DirectColorModel(
                                     ColorSpace.getInstance(ColorSpace.CS_sRGB),
                                     32,
                                     0x00ff0000,// Red
                                     0x0000ff00,// Green
                                     0x000000ff,// Blue
                                     0xff000000,// Alpha
                                     true,       // Alpha Premultiplied
                                     DataBuffer.TYPE_INT
                                     );

                  raster = colorModel.createCompatibleWritableRaster(width,
                                                                      height);
            }
        break;

        case TYPE_INT_BGR:
            {
                colorModel = new DirectColorModel(24,
                                                  0x000000ff,	// Red
                                                  0x0000ff00,	// Green
                                                  0x00ff0000	// Blue
                                                  );
                  raster = colorModel.createCompatibleWritableRaster(width,
                                                                      height);
            }
        break;

        case TYPE_3BYTE_BGR:
            {
                ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_sRGB);
                int[] nBits = {8, 8, 8};
                int[] bOffs = {2, 1, 0};
                colorModel = new ComponentColorModel(cs, nBits, false, false,
                                                     Transparency.OPAQUE,
                                                     DataBuffer.TYPE_BYTE);
                raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                        width, height,
                                                        width*3, 3,
                                                        bOffs, null);
            }
        break;
            
        case TYPE_4BYTE_ABGR:
            {
                ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_sRGB);
                int[] nBits = {8, 8, 8, 8};
                int[] bOffs = {3, 2, 1, 0};
                colorModel = new ComponentColorModel(cs, nBits, true, false,
                                                     Transparency.TRANSLUCENT,
                                                     DataBuffer.TYPE_BYTE);
                raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                        width, height,
                                                        width*4, 4,
                                                        bOffs, null);
            }
        break;

        case TYPE_4BYTE_ABGR_PRE:
            {
                ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_sRGB);
                int[] nBits = {8, 8, 8, 8};
                int[] bOffs = {3, 2, 1, 0};
                colorModel = new ComponentColorModel(cs, nBits, true, true,
                                                     Transparency.TRANSLUCENT,
                                                     DataBuffer.TYPE_BYTE);
                raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                        width, height,
                                                        width*4, 4,
                                                        bOffs, null);
            }
        break;

        case TYPE_BYTE_GRAY:
            {
                ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
                int[] nBits = {8};
                colorModel = new ComponentColorModel(cs, nBits, false, true,
                                                     Transparency.OPAQUE,
                                                     DataBuffer.TYPE_BYTE);
                raster = colorModel.createCompatibleWritableRaster(width,
                                                                   height);
            }
        break;
                
        case TYPE_USHORT_GRAY:
            {
                ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
                int[] nBits = {16};
                colorModel = new ComponentColorModel(cs, nBits, false, true,
                                                     Transparency.OPAQUE,
                                                     DataBuffer.TYPE_USHORT);
                raster = colorModel.createCompatibleWritableRaster(width,
                                                                   height);
            }
        break;
                
        case TYPE_BYTE_BINARY:
            {
                byte[] arr = {(byte)0, (byte)0xff};
                
                colorModel = new IndexColorModel(1, 2, arr, arr, arr);
                raster = Raster.createPackedRaster(DataBuffer.TYPE_BYTE,
                                                   width, height, 1, 1, null);
            }
        break;