imageutil.java

JAVA 所有包

/*
 * @(#)ImageUtil.java	1.3 05/11/17 14:14:58
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package com.sun.imageio.plugins.common;

import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Transparency;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.ComponentColorModel;
import java.awt.image.ComponentSampleModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.DataBufferInt;
import java.awt.image.DataBufferShort;
import java.awt.image.DataBufferUShort;
import java.awt.image.DirectColorModel;
import java.awt.image.IndexColorModel;
import java.awt.image.MultiPixelPackedSampleModel;
import java.awt.image.Raster;
import java.awt.image.RenderedImage;
import java.awt.image.SampleModel;
import java.awt.image.SinglePixelPackedSampleModel;
import java.awt.image.WritableRaster;
import java.util.Arrays;

//import javax.imageio.ImageTypeSpecifier;

import javax.imageio.IIOException;
import javax.imageio.IIOImage;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.ImageWriter;
import javax.imageio.spi.ImageWriterSpi;

public class ImageUtil {
    /* XXX testing only
    public static void main(String[] args) {
        ImageTypeSpecifier bilevel =
            ImageTypeSpecifier.createIndexed(new byte[] {(byte)0, (byte)255},
                                             new byte[] {(byte)0, (byte)255},
                                             new byte[] {(byte)0, (byte)255},
                                             null, 1,
                                             DataBuffer.TYPE_BYTE);
        ImageTypeSpecifier gray =
            ImageTypeSpecifier.createGrayscale(8, DataBuffer.TYPE_BYTE, false);
        ImageTypeSpecifier grayAlpha =
            ImageTypeSpecifier.createGrayscale(8, DataBuffer.TYPE_BYTE, false,
                                               false);
        ImageTypeSpecifier rgb =
            ImageTypeSpecifier.createInterleaved(ColorSpace.getInstance(ColorSpace.CS_sRGB),
                                                 new int[] {0, 1, 2},
                                                 DataBuffer.TYPE_BYTE,
                                                 false,
                                                 false);
        ImageTypeSpecifier rgba =
            ImageTypeSpecifier.createInterleaved(ColorSpace.getInstance(ColorSpace.CS_sRGB),
                                                 new int[] {0, 1, 2, 3},
                                                 DataBuffer.TYPE_BYTE,
                                                 true,
                                                 false);
        ImageTypeSpecifier packed =
            ImageTypeSpecifier.createPacked(ColorSpace.getInstance(ColorSpace.CS_sRGB),
                                            0xff000000,
                                            0x00ff0000,
                                            0x0000ff00,
                                            0x000000ff,
                                            DataBuffer.TYPE_BYTE,
                                            false);

        SampleModel bandedSM =
            new java.awt.image.BandedSampleModel(DataBuffer.TYPE_BYTE,
                                                 1, 1, 15);

        System.out.println(createColorModel(bilevel.getSampleModel()));
        System.out.println(createColorModel(gray.getSampleModel()));
        System.out.println(createColorModel(grayAlpha.getSampleModel()));
        System.out.println(createColorModel(rgb.getSampleModel()));
        System.out.println(createColorModel(rgba.getSampleModel()));
        System.out.println(createColorModel(packed.getSampleModel()));
        System.out.println(createColorModel(bandedSM));
    }
    */

    /**
     * Creates a <code>ColorModel</code> that may be used with the
     * specified <code>SampleModel</code>.  If a suitable
     * <code>ColorModel</code> cannot be found, this method returns
     * <code>null</code>.
     *
     * <p> Suitable <code>ColorModel</code>s are guaranteed to exist
     * for all instances of <code>ComponentSampleModel</code>.
     * For 1- and 3- banded <code>SampleModel</code>s, the returned
     * <code>ColorModel</code> will be opaque.  For 2- and 4-banded
     * <code>SampleModel</code>s, the output will use alpha transparency
     * which is not premultiplied.  1- and 2-banded data will use a
     * grayscale <code>ColorSpace</code>, and 3- and 4-banded data a sRGB
     * <code>ColorSpace</code>. Data with 5 or more bands will have a
     * <code>BogusColorSpace</code>.</p>
     *
     * <p>An instance of <code>DirectColorModel</code> will be created for
     * instances of <code>SinglePixelPackedSampleModel</code> with no more
     * than 4 bands.</p>
     *
     * <p>An instance of <code>IndexColorModel</code> will be created for
     * instances of <code>MultiPixelPackedSampleModel</code>. The colormap
     * will be a grayscale ramp with <code>1&nbsp;<<&nbsp;numberOfBits</code>
     * entries ranging from zero to at most 255.</p>
     *
     * @return An instance of <code>ColorModel</code> that is suitable for
     *         the supplied <code>SampleModel</code>, or <code>null</code>.
     *
     * @throws IllegalArgumentException  If <code>sampleModel</code> is
     *         <code>null</code>.
     */
    public static final ColorModel createColorModel(SampleModel sampleModel) {
        // Check the parameter.
        if(sampleModel == null) {
            throw new IllegalArgumentException("sampleModel == null!");
        }

        // Get the data type.
        int dataType = sampleModel.getDataType();

        // Check the data type
        switch(dataType) {
        case DataBuffer.TYPE_BYTE:
        case DataBuffer.TYPE_USHORT:
        case DataBuffer.TYPE_SHORT:
        case DataBuffer.TYPE_INT:
        case DataBuffer.TYPE_FLOAT:
        case DataBuffer.TYPE_DOUBLE:
            break;
        default:
            // Return null for other types.
            return null;
        }

        // The return variable.
        ColorModel colorModel = null;

        // Get the sample size.
        int[] sampleSize = sampleModel.getSampleSize();

        // Create a Component ColorModel.
        if(sampleModel instanceof ComponentSampleModel) {
            // Get the number of bands.
            int numBands = sampleModel.getNumBands();

            // Determine the color space.
            ColorSpace colorSpace = null;
            if(numBands <= 2) {
                colorSpace = ColorSpace.getInstance(ColorSpace.CS_GRAY);
            } else if(numBands <= 4) {
                colorSpace = ColorSpace.getInstance(ColorSpace.CS_sRGB);
            } else {
                colorSpace = new BogusColorSpace(numBands);
            }

            boolean hasAlpha = (numBands == 2) || (numBands == 4);
            boolean isAlphaPremultiplied = false;
            int transparency = hasAlpha ?
                Transparency.TRANSLUCENT : Transparency.OPAQUE;

            colorModel = new ComponentColorModel(colorSpace,
                                                 sampleSize,
                                                 hasAlpha,
                                                 isAlphaPremultiplied,
                                                 transparency,
                                                 dataType);
        } else if (sampleModel.getNumBands() <= 4 &&
                   sampleModel instanceof SinglePixelPackedSampleModel) {
            SinglePixelPackedSampleModel sppsm =
                (SinglePixelPackedSampleModel)sampleModel;

            int[] bitMasks = sppsm.getBitMasks();
            int rmask = 0;
            int gmask = 0;
            int bmask = 0;
            int amask = 0;

            int numBands = bitMasks.length;
            if (numBands <= 2) {
                rmask = gmask = bmask = bitMasks[0];
                if (numBands == 2) {
                    amask = bitMasks[1];
                }
            } else {
                rmask = bitMasks[0];
                gmask = bitMasks[1];
                bmask = bitMasks[2];
                if (numBands == 4) {
                    amask = bitMasks[3];
                }
            }

            int bits = 0;
            for (int i = 0; i < sampleSize.length; i++) {
                bits += sampleSize[i];
            }

            return new DirectColorModel(bits, rmask, gmask, bmask, amask);

        } else if(sampleModel instanceof MultiPixelPackedSampleModel) {
            // Load the colormap with a ramp.
            int bitsPerSample = sampleSize[0];
            int numEntries = 1 << bitsPerSample;
            byte[] map = new byte[numEntries];
            for (int i = 0; i < numEntries; i++) {
                map[i] = (byte)(i*255/(numEntries - 1));
            }

            colorModel = new IndexColorModel(bitsPerSample, numEntries,
                                             map, map, map);

        }

        return colorModel;
    }

    /**
     * For the case of binary data (<code>isBinary()</code> returns
     * <code>true</code>), return the binary data as a packed byte array.
     * The data will be packed as eight bits per byte with no bit offset,
     * i.e., the first bit in each image line will be the left-most of the
     * first byte of the line.  The line stride in bytes will be
     * <code>(int)((getWidth()+7)/8)</code>.  The length of the returned
     * array will be the line stride multiplied by <code>getHeight()</code>
     *
     * @return the binary data as a packed array of bytes with zero offset
     * of <code>null</code> if the data are not binary.
     * @throws IllegalArgumentException if <code>isBinary()</code> returns
     * <code>false</code> with the <code>SampleModel</code> of the
     * supplied <code>Raster</code> as argument.
     */
    public static byte[] getPackedBinaryData(Raster raster,
                                             Rectangle rect) {
        SampleModel sm = raster.getSampleModel();
        if(!isBinary(sm)) {
            throw new IllegalArgumentException(I18N.getString("ImageUtil0"));
        }

        int rectX = rect.x;
        int rectY = rect.y;
        int rectWidth = rect.width;
        int rectHeight = rect.height;

        DataBuffer dataBuffer = raster.getDataBuffer();

        int dx = rectX - raster.getSampleModelTranslateX();
        int dy = rectY - raster.getSampleModelTranslateY();

        MultiPixelPackedSampleModel mpp = (MultiPixelPackedSampleModel)sm;
        int lineStride = mpp.getScanlineStride();
        int eltOffset = dataBuffer.getOffset() + mpp.getOffset(dx, dy);
        int bitOffset = mpp.getBitOffset(dx);

        int numBytesPerRow = (rectWidth + 7)/8;
        if(dataBuffer instanceof DataBufferByte &&
           eltOffset == 0 && bitOffset == 0 &&
           numBytesPerRow == lineStride &&
           ((DataBufferByte)dataBuffer).getData().length ==
           numBytesPerRow*rectHeight) {
            return ((DataBufferByte)dataBuffer).getData();
        }

        byte[] binaryDataArray = new byte[numBytesPerRow*rectHeight];

        int b = 0;

        if(bitOffset == 0) {
            if(dataBuffer instanceof DataBufferByte) {
                byte[] data = ((DataBufferByte)dataBuffer).getData();
                int stride = numBytesPerRow;
                int offset = 0;
                for(int y = 0; y < rectHeight; y++) {
                    System.arraycopy(data, eltOffset,
                                     binaryDataArray, offset,
                                     stride);
                    offset += stride;
                    eltOffset += lineStride;
                }
            } else if(dataBuffer instanceof DataBufferShort ||
                      dataBuffer instanceof DataBufferUShort) {