pdfimage.java

一个java操作pdf文件的开发包,很好用的.

/*
 * $Id: PdfImage.java,v 1.32 2002/06/20 13:30:25 blowagie Exp $
 * $Name:  $
 *
 * Copyright 1999, 2000, 2001, 2002 Bruno Lowagie
 *
 * The contents of this file are subject to the Mozilla Public License Version 1.1
 * (the "License"); you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the License.
 *
 * The Original Code is 'iText, a free JAVA-PDF library'.
 *
 * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
 * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
 * All Rights Reserved.
 * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
 * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
 *
 * Contributor(s): all the names of the contributors are added in the source code
 * where applicable.
 *
 * Alternatively, the contents of this file may be used under the terms of the
 * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
 * provisions of LGPL are applicable instead of those above.  If you wish to
 * allow use of your version of this file only under the terms of the LGPL
 * License and not to allow others to use your version of this file under
 * the MPL, indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by the LGPL.
 * If you do not delete the provisions above, a recipient may use your version
 * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the MPL as stated above or under the terms of the GNU
 * Library General Public License as published by the Free Software Foundation;
 * either version 2 of the License, or any later version.
 *
 * This library 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 Library general Public License for more
 * details.
 *
 * If you didn't download this code from the following link, you should check if
 * you aren't using an obsolete version:
 * http://www.lowagie.com/iText/
 *
 * REMARK:
 * LZW/GIF is covered by a software patent which is owned by Unisys Corporation.
 * Unisys refuses to license this patent for PDF-related use in software
 * even when this software is released for free and may be freely distributed.
 * HOWEVER:
 * This library doesn't compress or decompress data using the LZW
 * algorithm, nor does it create or visualize GIF-images in any way;
 * it only copies parts of an existing GIF file into a PDF file.
 *
 * More information about the GIF format can be found in the following documents:
 * * GRAPHICS INTERCHANGE FORMAT(sm) Version 89a
 *   (c)1987,1988,1989,1990 Copyright CompuServe Incorporated. Columbus, Ohio
 * * LZW and GIF explained
 *   Steve Blackstock
 * * http://mistress.informatik.unibw-muenchen.de/
 *   very special thanks to [e-mail] for the algorithm
 *   to extract the LZW data from a GIF.
 */

package com.lowagie.text.pdf;

import com.lowagie.text.ExceptionConverter;
import com.lowagie.text.Image;
import com.lowagie.text.Png;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;

/**
 * <CODE>PdfImage</CODE> is a <CODE>PdfStream</CODE> containing an image-<CODE>Dictionary</CODE> and -stream.
 */

class PdfImage extends PdfStream {
    
    static final int TRANSFERSIZE = 4096;
    // membervariables
    
    /** This is the <CODE>PdfName</CODE> of the image. */
    protected PdfName name = null;
    
    // constructor
    
    /**
     * Constructs a <CODE>PdfImage</CODE>-object.
     *
     * @param image the <CODE>Image</CODE>-object
     * @param name the <CODE>PdfName</CODE> for this image
     * @throws BadPdfFormatException on error
     */
    
    public PdfImage(Image image, String name, PdfIndirectReference maskRef) throws BadPdfFormatException {
        super();
        this.name = new PdfName(name);
        put(PdfName.TYPE, PdfName.XOBJECT);
        put(PdfName.SUBTYPE, PdfName.IMAGE);
        put(PdfName.NAME, this.name);
        put(PdfName.WIDTH, new PdfNumber(image.width()));
        put(PdfName.HEIGHT, new PdfNumber(image.height()));
        if (maskRef != null)
            put(PdfName.MASK, maskRef);
        if (image.isMask() && image.isInvertMask())
            put(PdfName.DECODE, new PdfLiteral("[1 0]"));
        if (image.isInterpolation())
            put(PdfName.INTERPOLATE, PdfBoolean.PDFTRUE);
        InputStream is = null;
        try {
            
            // Raw Image data
            if (image.isImgRaw()) {
                // will also have the CCITT parameters
                int colorspace = image.colorspace();
                int transparency[] = image.getTransparency();
                if (transparency != null && !image.isMask() && maskRef == null) {
                    String s = "[";
                    for (int k = 0; k < transparency.length; ++k)
                        s += transparency[k] + " ";
                    s += "]";
                    put(PdfName.MASK, new PdfLiteral(s));
                }
                bytes = image.rawData();
                put(PdfName.LENGTH, new PdfNumber(bytes.length));
                int bpc = image.bpc();
                if (bpc > 0xff) {
                    if (!image.isMask())
                        put(PdfName.COLORSPACE, PdfName.DEVICEGRAY);
                    put(PdfName.BITSPERCOMPONENT, new PdfNumber(1));
                    put(PdfName.FILTER, PdfName.CCITTFAXDECODE);
                    int k = bpc - Image.CCITTG3_1D;
                    PdfDictionary decodeparms = new PdfDictionary();
                    if (k != 0)
                        decodeparms.put(PdfName.K, new PdfNumber(k));
                    if ((colorspace & Image.CCITT_BLACKIS1) != 0)
                        decodeparms.put(PdfName.BLACKIS1, PdfBoolean.PDFTRUE);
                    if ((colorspace & Image.CCITT_ENCODEDBYTEALIGN) != 0)
                        decodeparms.put(PdfName.ENCODEDBYTEALIGN, PdfBoolean.PDFTRUE);
                    if ((colorspace & Image.CCITT_ENDOFLINE) != 0)
                        decodeparms.put(PdfName.ENDOFLINE, PdfBoolean.PDFTRUE);
                    if ((colorspace & Image.CCITT_ENDOFBLOCK) != 0)
                        decodeparms.put(PdfName.ENDOFBLOCK, PdfBoolean.PDFFALSE);
                    decodeparms.put(PdfName.COLUMNS, new PdfNumber(image.width()));
                    decodeparms.put(PdfName.ROWS, new PdfNumber(image.height()));
                    put(PdfName.DECODEPARMS, decodeparms);
                }
                else {
                    if (!image.isMask()) {
                        switch(colorspace) {
                            case 1:
                                put(PdfName.COLORSPACE, PdfName.DEVICEGRAY);
                                break;
                            case 3:
                                put(PdfName.COLORSPACE, PdfName.DEVICERGB);
                                break;
                            case 4:
                            default:
                                put(PdfName.COLORSPACE, PdfName.DEVICECMYK);
                        }
                    }
                    put(PdfName.BITSPERCOMPONENT, new PdfNumber(image.bpc()));
                    try {
                        flateCompress();
                    }
                    catch(PdfException pe) {
                        throw new ExceptionConverter(pe);
                    }
                }
                if (image.isMask())
                    put(PdfName.IMAGEMASK, PdfBoolean.PDFTRUE);
                return;
            }
            
            // GIF, JPEG or PNG
            String errorID;
            if (image.rawData() == null){
                is = image.url().openStream();
                errorID = image.url().toString();
            }
            else{
                is = new java.io.ByteArrayInputStream(image.rawData());
                errorID = "Byte array";
            }
            streamBytes = new ByteArrayOutputStream();
            int i = 0;
            switch(image.type()) {
                case Image.PNG:
                    put(PdfName.FILTER, PdfName.FLATEDECODE);
                    for (int j = 0; j < Png.PNGID.length; j++) {
                        if (Png.PNGID[j] != is.read()) {
                            throw new BadPdfFormatException(errorID + " is not a PNG file.");
                        }
                    }
                    int colorType = 0;
                    while (true) {
                        int len = Png.getInt(is);
                        String marker = Png.getString(is);
                        if (Png.IDAT.equals(marker)) {
                            transferBytes(is, streamBytes, len);
                            Png.getInt(is);
                        }
                        else if (Png.tRNS.equals(marker) && !image.isMask() && maskRef == null) {
                            switch (colorType) {
                                case 0:
                                    if (len >= 2) {
                                        len -= 2;
                                        int gray = Png.getWord(is);
                                        put(PdfName.MASK, new PdfLiteral("["+gray+" "+gray+"]"));
                                    }
                                    break;
                                case 2:
                                    if (len >= 6) {
                                        len -= 6;
                                        int red = Png.getWord(is);
                                        int green = Png.getWord(is);
                                        int blue = Png.getWord(is);
                                        put(PdfName.MASK, new PdfLiteral("["+red+" "+red+" "+green+" "+green+" "+blue+" "+blue+"]"));
                                    }
                                    break;
                                case 3:
                                    if (len > 0) {
                                        int idx = 0;
                                        while (len-- != 0) {
                                            if (is.read() == 0) {
                                                put(PdfName.MASK, new PdfLiteral("["+idx+" "+idx+"]"));
                                                break;
                                            }
                                            ++idx;
                                        }
                                    }
                                    break;
                            }
                            Image.skip(is, len + 4);
                        }
                        else if (Png.IHDR.equals(marker)) {
                            int w = Png.getInt(is);
                            int h = Png.getInt(is);
                            
                            int bitDepth = is.read();
                            if (bitDepth == 16) {
                                throw new BadPdfFormatException(errorID + " Bit depth 16 is not suported.");
                            }
                            put(PdfName.BITSPERCOMPONENT, new PdfNumber(bitDepth));
                            
                            colorType = is.read();
                            if (! (colorType == 0 || colorType == 2 || colorType == 3)) {
                                throw new BadPdfFormatException(errorID + " Colortype " + colorType + " is not suported.");
                            }
                            if (colorType == 0) {
                                put(PdfName.COLORSPACE, PdfName.DEVICEGRAY);
                            }
                            else if (colorType == 2) {
                                put(PdfName.COLORSPACE, PdfName.DEVICERGB);