iText 5 itextpdf.jar Source Code

itextpdf.jar is a component in iText 5 Java library to provide core functionalities. iText Java library allows you to generate and manage PDF documents.

The Source Code files are provided at iText GitHub site.

You can compile it to generate your JAR file, using pom.xml as the build configuration file.

The source code of itextpdf-5.5.14.jar is provided below:

✍: FYIcenter.com

com/itextpdf/text/pdf/codec/PngImage.java

/*
 *
 * This file is part of the iText (R) project.
 * Copyright (c) 1998-2015 iText Group NV
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS
 *
 * This program 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 Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */

/*
 * This code is based on a series of source files originally released
 * by SUN in the context of the JAI project. The original code was released 
 * under the BSD license in a specific wording. In a mail dating from
 * January 23, 2008, Brian Burkhalter (@sun.com) gave us permission
 * to use the code under the following version of the BSD license:
 *
 * Copyright (c) 2005 Sun Microsystems, Inc. All  Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met: 
 * 
 * - Redistribution of source code must retain the above copyright 
 *   notice, this  list of conditions and the following disclaimer.
 * 
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in 
 *   the documentation and/or other materials provided with the
 *   distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of 
 * contributors may be used to endorse or promote products derived 
 * from this software without specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any 
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND 
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
 * EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL 
 * NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF 
 * USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR 
 * ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
 * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
 * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
 * INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES. 
 * 
 * You acknowledge that this software is not designed or intended for 
 * use in the design, construction, operation or maintenance of any 
 * nuclear facility.
 */

package com.itextpdf.text.pdf.codec;

import com.itextpdf.text.ExceptionConverter;
import com.itextpdf.text.Image;
import com.itextpdf.text.ImgRaw;
import com.itextpdf.text.Utilities;
import com.itextpdf.text.error_messages.MessageLocalization;
import com.itextpdf.text.log.Logger;
import com.itextpdf.text.log.LoggerFactory;
import com.itextpdf.text.pdf.ByteBuffer;
import com.itextpdf.text.pdf.ICC_Profile;
import com.itextpdf.text.pdf.PdfArray;
import com.itextpdf.text.pdf.PdfDictionary;
import com.itextpdf.text.pdf.PdfLiteral;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.PdfNumber;
import com.itextpdf.text.pdf.PdfObject;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfString;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.zip.Inflater;
import java.util.zip.InflaterInputStream;

/** Reads a PNG image. All types of PNG can be read.
 * <p>
 * It is based in part in the JAI codec.
 *
 * @author  Paulo Soares
 */
public class PngImage {
/** Some PNG specific values. */
    public static final int[] PNGID = {137, 80, 78, 71, 13, 10, 26, 10};
    
/** A PNG marker. */
    public static final String IHDR = "IHDR";
    
/** A PNG marker. */
    public static final String PLTE = "PLTE";
    
/** A PNG marker. */
    public static final String IDAT = "IDAT";
    
/** A PNG marker. */
    public static final String IEND = "IEND";
    
/** A PNG marker. */
    public static final String tRNS = "tRNS";
    
/** A PNG marker. */
    public static final String pHYs = "pHYs";
    
/** A PNG marker. */
    public static final String gAMA = "gAMA";
    
/** A PNG marker. */
    public static final String cHRM = "cHRM";
    
/** A PNG marker. */
    public static final String sRGB = "sRGB";
    
/** A PNG marker. */
    public static final String iCCP = "iCCP";
    
    private static final int TRANSFERSIZE = 4096;
    private static final int PNG_FILTER_NONE = 0;
    private static final int PNG_FILTER_SUB = 1;
    private static final int PNG_FILTER_UP = 2;
    private static final int PNG_FILTER_AVERAGE = 3;
    private static final int PNG_FILTER_PAETH = 4;
    private static final PdfName intents[] = {PdfName.PERCEPTUAL,
        PdfName.RELATIVECOLORIMETRIC,PdfName.SATURATION,PdfName.ABSOLUTECOLORIMETRIC};
    
    InputStream is;
    DataInputStream dataStream;
    int width;
    int height;
    int bitDepth;
    int colorType;
    int compressionMethod;
    int filterMethod;
    int interlaceMethod;
    PdfDictionary additional = new PdfDictionary();
    byte image[];
    byte smask[];
    byte trans[];
    NewByteArrayOutputStream idat = new NewByteArrayOutputStream();
    int dpiX;
    int dpiY;
    float XYRatio;
    boolean genBWMask;
    boolean palShades;
    int transRedGray = -1;
    int transGreen = -1;
    int transBlue = -1;
    int inputBands;
    int bytesPerPixel; // number of bytes per input pixel
    byte colorTable[];
    float gamma = 1f;
    boolean hasCHRM = false;
    float xW, yW, xR, yR, xG, yG, xB, yB;
    PdfName intent;
    ICC_Profile icc_profile;

    
    
    /** Creates a new instance of PngImage */
    PngImage(InputStream is) {
        this.is = is;
    }
    
    /** Reads a PNG from an url.
     * @param url the url
     * @throws IOException on error
     * @return the image
     */    
    public static Image getImage(URL url) throws IOException {
        InputStream is = null;
        try {
            is = url.openStream();
            Image img = getImage(is);
            img.setUrl(url);
            return img;
        }
        finally {
            if (is != null) {
                is.close();
            }
        }
    }
    
    /** Reads a PNG from a stream.
     * @param is the stream
     * @throws IOException on error
     * @return the image
     */    
    public static Image getImage(InputStream is) throws IOException {
        PngImage png = new PngImage(is);
        return png.getImage();
    }
    
    /** Reads a PNG from a file.
     * @param file the file
     * @throws IOException on error
     * @return the image
     */    
    public static Image getImage(String file) throws IOException {
        return getImage(Utilities.toURL(file));
    }
    
    /** Reads a PNG from a byte array.
     * @param data the byte array
     * @throws IOException on error
     * @return the image
     */    
    public static Image getImage(byte data[]) throws IOException {
        ByteArrayInputStream is = new ByteArrayInputStream(data);
        Image img = getImage(is);
        img.setOriginalData(data);
        return img;
    }
    
    boolean checkMarker(String s) {
        if (s.length() != 4)
            return false;
        for (int k = 0; k < 4; ++k) {
            char c = s.charAt(k);
            if ((c < 'a' || c > 'z') && (c < 'A' || c > 'Z'))
                return false;
        }
        return true;
    }
    
    void readPng() throws IOException {
        for (int i = 0; i < PNGID.length; i++) {
            if (PNGID[i] != is.read())	{
                throw new IOException(MessageLocalization.getComposedMessage("file.is.not.a.valid.png"));
            }
        }
        byte buffer[] = new byte[TRANSFERSIZE];
        while (true) {
            int len = getInt(is);
            String marker = getString(is);
            if (len < 0 || !checkMarker(marker))
                throw new IOException(MessageLocalization.getComposedMessage("corrupted.png.file"));
            if (IDAT.equals(marker)) {
                int size;
                while (len != 0) {
                    size = is.read(buffer, 0, Math.min(len, TRANSFERSIZE));
                    if (size < 0)
                        return;
                    idat.write(buffer, 0, size);
                    len -= size;
                }
            }
            else if (tRNS.equals(marker)) {
                switch (colorType) {
                    case 0:
                        if (len >= 2) {
                            len -= 2;
                            int gray = getWord(is);
                            if (bitDepth == 16)
                                transRedGray = gray;
                            else
                                additional.put(PdfName.MASK, new PdfLiteral("["+gray+" "+gray+"]"));
                        }
                        break;
                    case 2:
                        if (len >= 6) {
                            len -= 6;
                            int red = getWord(is);
                            int green = getWord(is);
                            int blue = getWord(is);
                            if (bitDepth == 16) {
                                transRedGray = red;
                                transGreen = green;
                                transBlue = blue;
                            }
                            else
                                additional.put(PdfName.MASK, new PdfLiteral("["+red+" "+red+" "+green+" "+green+" "+blue+" "+blue+"]"));
                        }
                        break;
                    case 3:
                        if (len > 0) {
                            trans = new byte[len];
                            for (int k = 0; k < len; ++k)
                                trans[k] = (byte)is.read();
                            len = 0;
                        }
                        break;
                }
                Utilities.skip(is, len);
            }
            else if (IHDR.equals(marker)) {
                width = getInt(is);
                height = getInt(is);
                
                bitDepth = is.read();
                colorType = is.read();
                compressionMethod = is.read();
                filterMethod = is.read();
                interlaceMethod = is.read();
            }
            else if (PLTE.equals(marker)) {
                if (colorType == 3) {
                    PdfArray colorspace = new PdfArray();
                    colorspace.add(PdfName.INDEXED);
                    colorspace.add(getColorspace());
                    colorspace.add(new PdfNumber(len / 3 - 1));
                    ByteBuffer colortable = new ByteBuffer();
                    while ((len--) > 0) {
                        colortable.append_i(is.read());
                    }
                    colorspace.add(new PdfString(colorTable = colortable.toByteArray()));
                    additional.put(PdfName.COLORSPACE, colorspace);
                }
                else {
                    Utilities.skip(is, len);
                }
            }
            else if (pHYs.equals(marker)) {
                int dx = getInt(is);
                int dy = getInt(is);
                int unit = is.read();
                if (unit == 1) {
                    dpiX = (int)(dx * 0.0254f + 0.5f);
                    dpiY = (int)(dy * 0.0254f + 0.5f);
                }
                else {
                    if (dy != 0)
                        XYRatio = (float)dx / (float)dy;
                }
            }
            else if (cHRM.equals(marker)) {
                xW = getInt(is) / 100000f;
                yW = getInt(is) / 100000f;
                xR = getInt(is) / 100000f;
                yR = getInt(is) / 100000f;
                xG = getInt(is) / 100000f;
                yG = getInt(is) / 100000f;
                xB = getInt(is) / 100000f;
                yB = getInt(is) / 100000f;
                hasCHRM = !(Math.abs(xW)<0.0001f||Math.abs(yW)<0.0001f||Math.abs(xR)<0.0001f||Math.abs(yR)<0.0001f||Math.abs(xG)<0.0001f||Math.abs(yG)<0.0001f||Math.abs(xB)<0.0001f||Math.abs(yB)<0.0001f);
            }
            else if (sRGB.equals(marker)) {
                int ri = is.read();
                intent = intents[ri];
                gamma = 2.2f;
                xW = 0.3127f;
                yW = 0.329f;
                xR = 0.64f;
                yR = 0.33f;
                xG = 0.3f;
                yG = 0.6f;
                xB = 0.15f;
                yB = 0.06f;
                hasCHRM = true;
            }
            else if (gAMA.equals(marker)) {
                int gm = getInt(is);
                if (gm != 0) {
                    gamma = 100000f / gm;
                    if (!hasCHRM) {
                        xW = 0.3127f;
                        yW = 0.329f;
                        xR = 0.64f;
                        yR = 0.33f;
                        xG = 0.3f;
                        yG = 0.6f;
                        xB = 0.15f;
                        yB = 0.06f;
                        hasCHRM = true;
                    }
                }
            }
            else if (iCCP.equals(marker)) {
                do {
                    --len;
                } while (is.read() != 0);
                is.read();
                --len;
                byte icccom[] = new byte[len];
                int p = 0;
                while (len > 0) {
                    int r = is.read(icccom, p, len);
                    if (r < 0)
                        throw new IOException(MessageLocalization.getComposedMessage("premature.end.of.file"));
                    p += r;
                    len -= r;
                }
                byte iccp[] = PdfReader.FlateDecode(icccom, true);
                icccom = null;
                try {
                    icc_profile = ICC_Profile.getInstance(iccp);
                }
                catch (RuntimeException e) {
                    icc_profile = null;
                }
            }
            else if (IEND.equals(marker)) {
                break;
            }
            else {
                Utilities.skip(is, len);
            }
            Utilities.skip(is, 4);
        }
    }
    
    PdfObject getColorspace() {
        if (icc_profile != null) {
            if ((colorType & 2) == 0)
                return PdfName.DEVICEGRAY;
            else
                return PdfName.DEVICERGB;
        }
        if (gamma == 1f && !hasCHRM) {
            if ((colorType & 2) == 0)
                return PdfName.DEVICEGRAY;
            else
                return PdfName.DEVICERGB;
        }
        else {
            PdfArray array = new PdfArray();
            PdfDictionary dic = new PdfDictionary();
            if ((colorType & 2) == 0) {
                if (gamma == 1f)
                    return PdfName.DEVICEGRAY;
                array.add(PdfName.CALGRAY);
                dic.put(PdfName.GAMMA, new PdfNumber(gamma));
                dic.put(PdfName.WHITEPOINT, new PdfLiteral("[1 1 1]"));
                array.add(dic);
            }
            else {
                PdfObject wp = new PdfLiteral("[1 1 1]");
                array.add(PdfName.CALRGB);
                if (gamma != 1f) {
                    PdfArray gm = new PdfArray();
                    PdfNumber n = new PdfNumber(gamma);
                    gm.add(n);
                    gm.add(n);
                    gm.add(n);
                    dic.put(PdfName.GAMMA, gm);
                }
                if (hasCHRM) {
                    float z = yW*((xG-xB)*yR-(xR-xB)*yG+(xR-xG)*yB);
                    float YA = yR*((xG-xB)*yW-(xW-xB)*yG+(xW-xG)*yB)/z;
                    float XA = YA*xR/yR;
                    float ZA = YA*((1-xR)/yR-1);
                    float YB = -yG*((xR-xB)*yW-(xW-xB)*yR+(xW-xR)*yB)/z;
                    float XB = YB*xG/yG;
                    float ZB = YB*((1-xG)/yG-1);
                    float YC = yB*((xR-xG)*yW-(xW-xG)*yW+(xW-xR)*yG)/z;
                    float XC = YC*xB/yB;
                    float ZC = YC*((1-xB)/yB-1);
                    float XW = XA+XB+XC;
                    float YW = 1;//YA+YB+YC;
                    float ZW = ZA+ZB+ZC;
                    PdfArray wpa = new PdfArray();
                    wpa.add(new PdfNumber(XW));
                    wpa.add(new PdfNumber(YW));
                    wpa.add(new PdfNumber(ZW));
                    wp = wpa;
                    PdfArray matrix = new PdfArray();
                    matrix.add(new PdfNumber(XA));
                    matrix.add(new PdfNumber(YA));
                    matrix.add(new PdfNumber(ZA));
                    matrix.add(new PdfNumber(XB));
                    matrix.add(new PdfNumber(YB));
                    matrix.add(new PdfNumber(ZB));
                    matrix.add(new PdfNumber(XC));
                    matrix.add(new PdfNumber(YC));
                    matrix.add(new PdfNumber(ZC));
                    dic.put(PdfName.MATRIX, matrix);
                }
                dic.put(PdfName.WHITEPOINT, wp);
                array.add(dic);
            }
            return array;
        }
    }
    
    Image getImage() throws IOException {
        readPng();
        checkIccProfile();
        try {
            int pal0 = 0;
            int palIdx = 0;
            palShades = false;
            if (trans != null) {
                for (int k = 0; k < trans.length; ++k) {
                    int n = trans[k] & 0xff;
                    if (n == 0) {
                        ++pal0;
                        palIdx = k;
                    }
                    if (n != 0 && n != 255) {
                        palShades = true;
                        break;
                    }
                }
            }
            if ((colorType & 4) != 0)
                palShades = true;
            genBWMask = (!palShades && (pal0 > 1 || transRedGray >= 0));
            if (!palShades && !genBWMask && pal0 == 1) {
                additional.put(PdfName.MASK, new PdfLiteral("["+palIdx+" "+palIdx+"]"));
            }
            boolean needDecode = (interlaceMethod == 1) || (bitDepth == 16) || ((colorType & 4) != 0) || palShades || genBWMask;
            switch (colorType) {
                case 0:
                    inputBands = 1;
                    break;
                case 2:
                    inputBands = 3;
                    break;
                case 3:
                    inputBands = 1;
                    break;
                case 4:
                    inputBands = 2;
                    break;
                case 6:
                    inputBands = 4;
                    break;
            }
            if (needDecode)
                decodeIdat();
            int components = inputBands;
            if ((colorType & 4) != 0)
                --components;
            int bpc = bitDepth;
            if (bpc == 16)
                bpc = 8;
            Image img;
            if (image != null) {
                if (colorType == 3)
                    img = new ImgRaw(width, height, components, bpc, image);
                else
                    img = Image.getInstance(width, height, components, bpc, image);
            }
            else {
                img = new ImgRaw(width, height, components, bpc, idat.toByteArray());
                img.setDeflated(true);
                PdfDictionary decodeparms = new PdfDictionary();
                decodeparms.put(PdfName.BITSPERCOMPONENT, new PdfNumber(bitDepth));
                decodeparms.put(PdfName.PREDICTOR, new PdfNumber(15));
                decodeparms.put(PdfName.COLUMNS, new PdfNumber(width));
                decodeparms.put(PdfName.COLORS, new PdfNumber((colorType == 3 || (colorType & 2) == 0) ? 1 : 3));
                additional.put(PdfName.DECODEPARMS, decodeparms);
            }
            if (additional.get(PdfName.COLORSPACE) == null)
                additional.put(PdfName.COLORSPACE, getColorspace());
            if (intent != null)
                additional.put(PdfName.INTENT, intent);
            if (additional.size() > 0)
                img.setAdditional(additional);
            if (icc_profile != null)
                img.tagICC(icc_profile);
            if (palShades) {
                Image im2 = Image.getInstance(width, height, 1, 8, smask);
                im2.makeMask();
                img.setImageMask(im2);
            }
            if (genBWMask) {
                Image im2 = Image.getInstance(width, height, 1, 1, smask);
                im2.makeMask();
                img.setImageMask(im2);
            }
            img.setDpi(dpiX, dpiY);
            img.setXYRatio(XYRatio);
            img.setOriginalType(Image.ORIGINAL_PNG);
            return img;
        }
        catch (Exception e) {
            throw new ExceptionConverter(e);
        }
    }
    
    void decodeIdat() {
        int nbitDepth = bitDepth;
        if (nbitDepth == 16)
            nbitDepth = 8;
        int size = -1;
        bytesPerPixel = (bitDepth == 16) ? 2 : 1;
        switch (colorType) {
            case 0:
                size = (nbitDepth * width + 7) / 8 * height;
                break;
            case 2:
                size = width * 3 * height;
                bytesPerPixel *= 3;
                break;
            case 3:
                if (interlaceMethod == 1)
                    size = (nbitDepth * width + 7) / 8 * height;
                bytesPerPixel = 1;
                break;
            case 4:
                size = width * height;
                bytesPerPixel *= 2;
                break;
            case 6:
                size = width * 3 * height;
                bytesPerPixel *= 4;
                break;
        }
        if (size >= 0)
            image = new byte[size];
        if (palShades)
            smask = new byte[width * height];
        else if (genBWMask)
            smask = new byte[(width + 7) / 8 * height];
        ByteArrayInputStream bai = new ByteArrayInputStream(idat.getBuf(), 0, idat.size());
        InputStream infStream = new InflaterInputStream(bai, new Inflater());
        this.dataStream = new DataInputStream(infStream);
        
        if (interlaceMethod != 1) {
            decodePass(0, 0, 1, 1, width, height);
        }
        else {
            decodePass(0, 0, 8, 8, (width + 7)/8, (height + 7)/8);
            decodePass(4, 0, 8, 8, (width + 3)/8, (height + 7)/8);
            decodePass(0, 4, 4, 8, (width + 3)/4, (height + 3)/8);
            decodePass(2, 0, 4, 4, (width + 1)/4, (height + 3)/4);
            decodePass(0, 2, 2, 4, (width + 1)/2, (height + 1)/4);
            decodePass(1, 0, 2, 2, width/2, (height + 1)/2);
            decodePass(0, 1, 1, 2, width, height/2);
        }

        try {
            this.dataStream.close();
        } catch (IOException e) {
            Logger logger = LoggerFactory.getLogger(this.getClass());
            logger.warn("Datastream of PngImage#decodeIdat didn't close properly.");
        }
    }
    
    void decodePass( int xOffset, int yOffset,
    int xStep, int yStep,
    int passWidth, int passHeight) {
        if ((passWidth == 0) || (passHeight == 0)) {
            return;
        }
        
        int bytesPerRow = (inputBands*passWidth*bitDepth + 7)/8;
        byte[] curr = new byte[bytesPerRow];
        byte[] prior = new byte[bytesPerRow];
        
        // Decode the (sub)image row-by-row
        int srcY, dstY;
        for (srcY = 0, dstY = yOffset;
        srcY < passHeight;
        srcY++, dstY += yStep) {
            // Read the filter type byte and a row of data
            int filter = 0;
            try {
                filter = dataStream.read();
                dataStream.readFully(curr, 0, bytesPerRow);
            } catch (Exception e) {
                // empty on purpose
            }
            
            switch (filter) {
                case PNG_FILTER_NONE:
                    break;
                case PNG_FILTER_SUB:
                    decodeSubFilter(curr, bytesPerRow, bytesPerPixel);
                    break;
                case PNG_FILTER_UP:
                    decodeUpFilter(curr, prior, bytesPerRow);
                    break;
                case PNG_FILTER_AVERAGE:
                    decodeAverageFilter(curr, prior, bytesPerRow, bytesPerPixel);
                    break;
                case PNG_FILTER_PAETH:
                    decodePaethFilter(curr, prior, bytesPerRow, bytesPerPixel);
                    break;
                default:
                    // Error -- uknown filter type
                    throw new RuntimeException(MessageLocalization.getComposedMessage("png.filter.unknown"));
            }
            
            processPixels(curr, xOffset, xStep, dstY, passWidth);
            
            // Swap curr and prior
            byte[] tmp = prior;
            prior = curr;
            curr = tmp;
        }
    }
    
    void processPixels(byte curr[], int xOffset, int step, int y, int width) {
        int srcX, dstX;

        int out[] = getPixel(curr);
        int sizes = 0;
        switch (colorType) {
            case 0:
            case 3:
            case 4:
                sizes = 1;
                break;
            case 2:
            case 6:
                sizes = 3;
                break;
        }
        if (image != null) {
            dstX = xOffset;
            int yStride = (sizes*this.width*(bitDepth == 16 ? 8 : bitDepth)+ 7)/8;
            for (srcX = 0; srcX < width; srcX++) {
                setPixel(image, out, inputBands * srcX, sizes, dstX, y, bitDepth, yStride);
                dstX += step;
            }
        }
        if (palShades) {
            if ((colorType & 4) != 0) {
                if (bitDepth == 16) {
                    for (int k = 0; k < width; ++k)
                        out[k * inputBands + sizes] >>>= 8;
                }
                int yStride = this.width;
                dstX = xOffset;
                for (srcX = 0; srcX < width; srcX++) {
                    setPixel(smask, out, inputBands * srcX + sizes, 1, dstX, y, 8, yStride);
                    dstX += step;
                }
            }
            else { //colorType 3
                int yStride = this.width;
                int v[] = new int[1];
                dstX = xOffset;
                for (srcX = 0; srcX < width; srcX++) {
                    int idx = out[srcX];
                    if (idx < trans.length)
                        v[0] = trans[idx];
                    else
                    	v[0] = 255; // Patrick Valsecchi
                    setPixel(smask, v, 0, 1, dstX, y, 8, yStride);
                    dstX += step;
                }
            }
        }
        else if (genBWMask) {
            switch (colorType) {
                case 3: {
                    int yStride = (this.width + 7) / 8;
                    int v[] = new int[1];
                    dstX = xOffset;
                    for (srcX = 0; srcX < width; srcX++) {
                        int idx = out[srcX];
                        v[0] = ((idx < trans.length && trans[idx] == 0) ? 1 : 0);
                        setPixel(smask, v, 0, 1, dstX, y, 1, yStride);
                        dstX += step;
                    }
                    break;
                }
                case 0: {
                    int yStride = (this.width + 7) / 8;
                    int v[] = new int[1];
                    dstX = xOffset;
                    for (srcX = 0; srcX < width; srcX++) {
                        int g = out[srcX];
                        v[0] = (g == transRedGray ? 1 : 0);
                        setPixel(smask, v, 0, 1, dstX, y, 1, yStride);
                        dstX += step;
                    }
                    break;
                }
                case 2: {
                    int yStride = (this.width + 7) / 8;
                    int v[] = new int[1];
                    dstX = xOffset;
                    for (srcX = 0; srcX < width; srcX++) {
                        int markRed = inputBands * srcX;
                        v[0] = (out[markRed] == transRedGray && out[markRed + 1] == transGreen 
                            && out[markRed + 2] == transBlue ? 1 : 0);
                        setPixel(smask, v, 0, 1, dstX, y, 1, yStride);
                        dstX += step;
                    }
                    break;
                }
            }
        }
    }
    
    static int getPixel(byte image[], int x, int y, int bitDepth, int bytesPerRow) {
        if (bitDepth == 8) {
            int pos = bytesPerRow * y + x;
            return image[pos] & 0xff;
        }
        else {
            int pos = bytesPerRow * y + x / (8 / bitDepth);
            int v = image[pos] >> (8 - bitDepth * (x % (8 / bitDepth))- bitDepth);
            return v & ((1 << bitDepth) - 1);
        }
    }
    
    static void setPixel(byte image[], int data[], int offset, int size, int x, int y, int bitDepth, int bytesPerRow) {
        if (bitDepth == 8) {
            int pos = bytesPerRow * y + size * x;
            for (int k = 0; k < size; ++k)
                image[pos + k] = (byte)data[k + offset];
        }
        else if (bitDepth == 16) {
            int pos = bytesPerRow * y + size * x;
            for (int k = 0; k < size; ++k)
                image[pos + k] = (byte)(data[k + offset] >>> 8);
        }
        else {
            int pos = bytesPerRow * y + x / (8 / bitDepth);
            int v = data[offset] << (8 - bitDepth * (x % (8 / bitDepth))- bitDepth);
            image[pos] |= v;
        }
    }
    
    int[] getPixel(byte curr[]) {
        switch (bitDepth) {
            case 8: {
                int out[] = new int[curr.length];
                for (int k = 0; k < out.length; ++k)
                    out[k] = curr[k] & 0xff;
                return out;
            }
            case 16: {
                int out[] = new int[curr.length / 2];
                for (int k = 0; k < out.length; ++k)
                    out[k] = ((curr[k * 2] & 0xff) << 8) + (curr[k * 2 + 1] & 0xff);
                return out;
            }
            default: {
                int out[] = new int[curr.length * 8 / bitDepth];
                int idx = 0;
                int passes = 8 / bitDepth;
                int mask = (1 << bitDepth) - 1;
                for (int k = 0; k < curr.length; ++k) {
                    for (int j = passes - 1; j >= 0; --j) {
                        out[idx++] = (curr[k] >>> (bitDepth * j)) & mask; 
                    }
                }
                return out;
            }
        }
    }

    private int getExpectedIccNumberOfComponents() {
        if (colorType == 0 || colorType == 4) {
            return 1;
        } else {
            return 3;
        }
    }

    private void checkIccProfile() {
        if (icc_profile != null && icc_profile.getNumComponents() != getExpectedIccNumberOfComponents()) {
            LoggerFactory.getLogger(getClass()).warn(MessageLocalization.getComposedMessage("unexpected.color.space.in.embedded.icc.profile"));
            icc_profile = null;
        }
    }
    
    private static void decodeSubFilter(byte[] curr, int count, int bpp) {
        for (int i = bpp; i < count; i++) {
            int val;
            
            val = curr[i] & 0xff;
            val += curr[i - bpp] & 0xff;
            
            curr[i] = (byte)val;
        }
    }
    
    private static void decodeUpFilter(byte[] curr, byte[] prev,
    int count) {
        for (int i = 0; i < count; i++) {
            int raw = curr[i] & 0xff;
            int prior = prev[i] & 0xff;
            
            curr[i] = (byte)(raw + prior);
        }
    }
    
    private static void decodeAverageFilter(byte[] curr, byte[] prev,
    int count, int bpp) {
        int raw, priorPixel, priorRow;
        
        for (int i = 0; i < bpp; i++) {
            raw = curr[i] & 0xff;
            priorRow = prev[i] & 0xff;
            
            curr[i] = (byte)(raw + priorRow/2);
        }
        
        for (int i = bpp; i < count; i++) {
            raw = curr[i] & 0xff;
            priorPixel = curr[i - bpp] & 0xff;
            priorRow = prev[i] & 0xff;
            
            curr[i] = (byte)(raw + (priorPixel + priorRow)/2);
        }
    }
    
    private static int paethPredictor(int a, int b, int c) {
        int p = a + b - c;
        int pa = Math.abs(p - a);
        int pb = Math.abs(p - b);
        int pc = Math.abs(p - c);
        
        if ((pa <= pb) && (pa <= pc)) {
            return a;
        } else if (pb <= pc) {
            return b;
        } else {
            return c;
        }
    }
    
    private static void decodePaethFilter(byte[] curr, byte[] prev,
    int count, int bpp) {
        int raw, priorPixel, priorRow, priorRowPixel;
        
        for (int i = 0; i < bpp; i++) {
            raw = curr[i] & 0xff;
            priorRow = prev[i] & 0xff;
            
            curr[i] = (byte)(raw + priorRow);
        }
        
        for (int i = bpp; i < count; i++) {
            raw = curr[i] & 0xff;
            priorPixel = curr[i - bpp] & 0xff;
            priorRow = prev[i] & 0xff;
            priorRowPixel = prev[i - bpp] & 0xff;
            
            curr[i] = (byte)(raw + paethPredictor(priorPixel,
            priorRow,
            priorRowPixel));
        }
    }
    
    static class NewByteArrayOutputStream extends ByteArrayOutputStream {
        public byte[] getBuf() {
            return buf;
        }
    }

/**
 * Gets an <CODE>int</CODE> from an <CODE>InputStream</CODE>.
 *
 * @param		is      an <CODE>InputStream</CODE>
 * @return		the value of an <CODE>int</CODE>
 */
    
    public static final int getInt(InputStream is) throws IOException {
        return (is.read() << 24) + (is.read() << 16) + (is.read() << 8) + is.read();
    }
    
/**
 * Gets a <CODE>word</CODE> from an <CODE>InputStream</CODE>.
 *
 * @param		is      an <CODE>InputStream</CODE>
 * @return		the value of an <CODE>int</CODE>
 */
    
    public static final int getWord(InputStream is) throws IOException {
        return (is.read() << 8) + is.read();
    }
    
/**
 * Gets a <CODE>String</CODE> from an <CODE>InputStream</CODE>.
 *
 * @param		is      an <CODE>InputStream</CODE>
 * @return		the value of an <CODE>int</CODE>
 */
    
    public static final String getString(InputStream is) throws IOException {
        StringBuffer buf = new StringBuffer();
        for (int i = 0; i < 4; i++) {
            buf.append((char)is.read());
        }
        return buf.toString();
    }

}

com/itextpdf/text/pdf/codec/PngImage.java

 

⇒ iText-2.1.6.jar - iText, a JAVA-PDF library

⇐ iText layout.jar Source Code

⇑ Download and Install iText Java Library

⇑⇑ iText for PDF Generation

2021-07-03, 48061👍, 0💬