jpegimagewriter.java

java1.6众多例子参考

/*
 * @(#)JPEGImageWriter.java	1.33 03/10/01
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package com.sun.imageio.plugins.jpeg;

import javax.imageio.IIOException;
import javax.imageio.ImageWriter;
import javax.imageio.ImageWriteParam;
import javax.imageio.IIOImage;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataFormatImpl;
import javax.imageio.metadata.IIOInvalidTreeException;
import javax.imageio.spi.ImageWriterSpi;
import javax.imageio.stream.ImageOutputStream;
import javax.imageio.plugins.jpeg.JPEGImageWriteParam;
import javax.imageio.plugins.jpeg.JPEGQTable;
import javax.imageio.plugins.jpeg.JPEGHuffmanTable;

import org.w3c.dom.Node;

import java.awt.image.Raster;
import java.awt.image.WritableRaster;
import java.awt.image.SampleModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.ColorModel;
import java.awt.image.IndexColorModel;
import java.awt.image.ColorConvertOp;
import java.awt.image.RenderedImage;
import java.awt.image.BufferedImage;
import java.awt.color.ColorSpace;
import java.awt.color.ICC_ColorSpace;
import java.awt.color.ICC_Profile;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Transparency;

import java.io.IOException;

import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;

import sun.java2d.Disposer;
import sun.java2d.DisposerRecord;

public class JPEGImageWriter extends ImageWriter {

    ///////// Private variables

    private boolean debug = false;

    /**
     * The following variable contains a pointer to the IJG library 
     * structure for this reader.  It is assigned in the constructor
     * and then is passed in to every native call.  It is set to 0
     * by dispose to avoid disposing twice.
     */
    private long structPointer = 0;


    /** The output stream we write to */
    private ImageOutputStream ios = null;

    /** The Raster we will write from */
    private Raster srcRas = null;
    
    /** An intermediate Raster holding compressor-friendly data */
    private WritableRaster raster = null;

    /** 
     * Set to true if we are writing an image with an 
     * indexed ColorModel 
     */
    private boolean indexed = false;
    private IndexColorModel indexCM = null;

    private boolean convertTosRGB = false;  // Used by PhotoYCC only
    private WritableRaster converted = null;

    private boolean isAlphaPremultiplied = false;
    private ColorModel srcCM = null;

    /**
     * If there are thumbnails to be written, this is the list.
     */
    private List thumbnails = null;

    /**
     * If metadata should include an icc profile, store it here.
     */
    private ICC_Profile iccProfile = null;
    
    private int sourceXOffset = 0;
    private int sourceYOffset = 0;
    private int sourceWidth = 0;
    private int [] srcBands = null;
    private int sourceHeight = 0;

    /** Used when calling listeners */
    private int currentImage = 0;

    private ColorConvertOp convertOp = null;

    private JPEGQTable [] streamQTables = null;
    private JPEGHuffmanTable[] streamDCHuffmanTables = null;
    private JPEGHuffmanTable[] streamACHuffmanTables = null;

    // Parameters for writing metadata
    private boolean ignoreJFIF = false;  // If it's there, use it
    private boolean forceJFIF = false;  // Add one for the thumbnails
    private boolean ignoreAdobe = false;  // If it's there, use it
    private int newAdobeTransform = JPEG.ADOBE_IMPOSSIBLE;  // Change if needed
    private boolean writeDefaultJFIF = false;
    private boolean writeAdobe = false;
    private JPEGMetadata metadata = null;
    
    private boolean sequencePrepared = false;

    private int numScans = 0;

    /** The referent to be registered with the Disposer. */
    private Object disposerReferent = new Object();

    /** The DisposerRecord that handles the actual disposal of this writer. */
    private DisposerRecord disposerRecord;

    ///////// End of Private variables

    ///////// Protected variables

    protected static final int WARNING_DEST_IGNORED = 0;
    protected static final int WARNING_STREAM_METADATA_IGNORED = 1;
    protected static final int WARNING_DEST_METADATA_COMP_MISMATCH = 2;
    protected static final int WARNING_DEST_METADATA_JFIF_MISMATCH = 3;
    protected static final int WARNING_DEST_METADATA_ADOBE_MISMATCH = 4;
    protected static final int WARNING_IMAGE_METADATA_JFIF_MISMATCH = 5;
    protected static final int WARNING_IMAGE_METADATA_ADOBE_MISMATCH = 6;
    protected static final int WARNING_METADATA_NOT_JPEG_FOR_RASTER = 7;
    protected static final int WARNING_NO_BANDS_ON_INDEXED = 8;
    protected static final int WARNING_ILLEGAL_THUMBNAIL = 9;
    protected static final int WARNING_IGNORING_THUMBS = 10;
    protected static final int WARNING_FORCING_JFIF = 11;
    protected static final int WARNING_THUMB_CLIPPED = 12;
    protected static final int WARNING_METADATA_ADJUSTED_FOR_THUMB = 13;
    protected static final int WARNING_NO_RGB_THUMB_AS_INDEXED = 14;
    protected static final int WARNING_NO_GRAY_THUMB_AS_INDEXED = 15;

    private static final int MAX_WARNING = WARNING_NO_GRAY_THUMB_AS_INDEXED;

    ///////// End of Protected variables
    
    ///////// static initializer
    
    static {
        java.security.AccessController.doPrivileged(
            new sun.security.action.LoadLibraryAction("jpeg"));
        initWriterIDs(ImageOutputStream.class, 
                      JPEGQTable.class, 
                      JPEGHuffmanTable.class);
    }

    //////// Public API

    public JPEGImageWriter(ImageWriterSpi originator) {
        super(originator);
        structPointer = initJPEGImageWriter();
        disposerRecord = new JPEGWriterDisposerRecord(structPointer);
        Disposer.addRecord(disposerReferent, disposerRecord);
    }

    public void setOutput(Object output) {
        super.setOutput(output); // validates output
        resetInternalState();
        ios = (ImageOutputStream) output; // so this will always work
        // Set the native destination
        setDest(structPointer, ios);
    }

    public ImageWriteParam getDefaultWriteParam() {
        return new JPEGImageWriteParam(null);
    }

    public IIOMetadata getDefaultStreamMetadata(ImageWriteParam param) {
        return new JPEGMetadata(param, this);
    }

    public IIOMetadata
        getDefaultImageMetadata(ImageTypeSpecifier imageType,
                                ImageWriteParam param) {
        return new JPEGMetadata(imageType, param, this);
    }

    public IIOMetadata convertStreamMetadata(IIOMetadata inData,
                                             ImageWriteParam param) {
        // There isn't much we can do.  If it's one of ours, then
        // return it.  Otherwise just return null.  We use it only
        // for tables, so we can't get a default and modify it,
        // as this will usually not be what is intended.
        if (inData instanceof JPEGMetadata) {
            JPEGMetadata jpegData = (JPEGMetadata) inData;
            if (jpegData.isStream) {
                return inData;
            }
        }
        return null;
    }

    public IIOMetadata
        convertImageMetadata(IIOMetadata inData,
                             ImageTypeSpecifier imageType,
                             ImageWriteParam param) {
        // If it's one of ours, just return it
        if (inData instanceof JPEGMetadata) {
            JPEGMetadata jpegData = (JPEGMetadata) inData;
            if (!jpegData.isStream) {
                return inData;
            } else {
                // Can't convert stream metadata to image metadata
                // XXX Maybe this should put out a warning?
                return null;
            }
        }
        // If it's not one of ours, create a default and set it from
        // the standard tree from the input, if it exists.
        if (inData.isStandardMetadataFormatSupported()) {
            String formatName = 
                IIOMetadataFormatImpl.standardMetadataFormatName;
            Node tree = inData.getAsTree(formatName);
            if (tree != null) {
                JPEGMetadata jpegData = new JPEGMetadata(imageType,
                                                         param,
                                                         this);
                try {
                    jpegData.setFromTree(formatName, tree);
                } catch (IIOInvalidTreeException e) {
                    // Other plug-in generates bogus standard tree
                    // XXX Maybe this should put out a warning?
                    return null;
                }

                return jpegData;
            }
        }
            return null;
    }

    public int getNumThumbnailsSupported(ImageTypeSpecifier imageType,
                                         ImageWriteParam param,
                                         IIOMetadata streamMetadata,
                                         IIOMetadata imageMetadata) {
        if (jfifOK(imageType, param, streamMetadata, imageMetadata)) {
            return Integer.MAX_VALUE;
        } 
        return 0;
    }

    static final Dimension [] preferredThumbSizes = {new Dimension(1, 1), 
                                                     new Dimension(255, 255)};
    
    public Dimension[] getPreferredThumbnailSizes(ImageTypeSpecifier imageType,
                                                  ImageWriteParam param,
                                                  IIOMetadata streamMetadata,
                                                  IIOMetadata imageMetadata) {
        if (jfifOK(imageType, param, streamMetadata, imageMetadata)) {
            return (Dimension [])preferredThumbSizes.clone();
        }
        return null;
    }

    private boolean jfifOK(ImageTypeSpecifier imageType,
                           ImageWriteParam param,
                           IIOMetadata streamMetadata,
                           IIOMetadata imageMetadata) {
        // If the image type and metadata are JFIF compatible, return true
        if ((imageType != null) &&
            (!JPEG.isJFIFcompliant(imageType, true))) {
            return false;
        }
        if (imageMetadata != null) {
            JPEGMetadata metadata = null;
            if (imageMetadata instanceof JPEGMetadata) {
                metadata = (JPEGMetadata) imageMetadata;
            } else {
                metadata = (JPEGMetadata)convertImageMetadata(imageMetadata,
                                                              imageType,
                                                              param);
            }
            // metadata must have a jfif node
            if (metadata.findMarkerSegment
                (JFIFMarkerSegment.class, true) == null){
                return false;
            }
        }
        return true;
    }

    public boolean canWriteRasters() {
        return true;
    }

    public void write(IIOMetadata streamMetadata,
                      IIOImage image,
                      ImageWriteParam param) throws IOException {

        if (ios == null) {
            throw new IllegalStateException("Output has not been set!");
        }

        if (image == null) {
            throw new IllegalArgumentException("image is null!");
        }

        // if streamMetadata is not null, issue a warning
        if (streamMetadata != null) {
            warningOccurred(WARNING_STREAM_METADATA_IGNORED);
        }

        // Obtain the raster and image, if there is one
        boolean rasterOnly = image.hasRaster();

        RenderedImage rimage = null;