Java tutorial
/* * $Id: Jpeg.java 3970 2009-06-16 08:09:54Z blowagie $ * * Copyright 1999, 2000, 2001, 2002 by 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/ */ package com.lowagie.text; import java.awt.color.ICC_Profile; import java.io.IOException; import java.io.InputStream; import java.net.URL; /** * An <CODE>Jpeg</CODE> is the representation of a graphic element (JPEG) * that has to be inserted into the document * * @see Element * @see Image */ public class Jpeg extends Image { // public static final membervariables /** This is a type of marker. */ public static final int NOT_A_MARKER = -1; /** This is a type of marker. */ public static final int VALID_MARKER = 0; /** Acceptable Jpeg markers. */ public static final int[] VALID_MARKERS = { 0xC0, 0xC1, 0xC2 }; /** This is a type of marker. */ public static final int UNSUPPORTED_MARKER = 1; /** Unsupported Jpeg markers. */ public static final int[] UNSUPPORTED_MARKERS = { 0xC3, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xCB, 0xCD, 0xCE, 0xCF }; /** This is a type of marker. */ public static final int NOPARAM_MARKER = 2; /** Jpeg markers without additional parameters. */ public static final int[] NOPARAM_MARKERS = { 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0x01 }; /** Marker value */ public static final int M_APP0 = 0xE0; /** Marker value */ public static final int M_APP2 = 0xE2; /** Marker value */ public static final int M_APPE = 0xEE; /** sequence that is used in all Jpeg files */ public static final byte JFIF_ID[] = { 0x4A, 0x46, 0x49, 0x46, 0x00 }; private byte[][] icc; // Constructors Jpeg(Image image) { super(image); } /** * Constructs a <CODE>Jpeg</CODE>-object, using an <VAR>url</VAR>. * * @param url the <CODE>URL</CODE> where the image can be found * @throws BadElementException * @throws IOException */ public Jpeg(URL url) throws BadElementException, IOException { super(url); processParameters(); } /** * Constructs a <CODE>Jpeg</CODE>-object from memory. * * @param img the memory image * @throws BadElementException * @throws IOException */ public Jpeg(byte[] img) throws BadElementException, IOException { super((URL) null); rawData = img; originalData = img; processParameters(); } /** * Constructs a <CODE>Jpeg</CODE>-object from memory. * * @param img the memory image. * @param width the width you want the image to have * @param height the height you want the image to have * @throws BadElementException * @throws IOException */ public Jpeg(byte[] img, float width, float height) throws BadElementException, IOException { this(img); scaledWidth = width; scaledHeight = height; } // private static methods /** * Reads a short from the <CODE>InputStream</CODE>. * * @param is the <CODE>InputStream</CODE> * @return an int * @throws IOException */ private static final int getShort(InputStream is) throws IOException { return (is.read() << 8) + is.read(); } /** * Returns a type of marker. * * @param marker an int * @return a type: <VAR>VALID_MARKER</CODE>, <VAR>UNSUPPORTED_MARKER</VAR> or <VAR>NOPARAM_MARKER</VAR> */ private static final int marker(int marker) { for (int i = 0; i < VALID_MARKERS.length; i++) { if (marker == VALID_MARKERS[i]) { return VALID_MARKER; } } for (int i = 0; i < NOPARAM_MARKERS.length; i++) { if (marker == NOPARAM_MARKERS[i]) { return NOPARAM_MARKER; } } for (int i = 0; i < UNSUPPORTED_MARKERS.length; i++) { if (marker == UNSUPPORTED_MARKERS[i]) { return UNSUPPORTED_MARKER; } } return NOT_A_MARKER; } // private methods /** * This method checks if the image is a valid JPEG and processes some parameters. * @throws BadElementException * @throws IOException */ private void processParameters() throws BadElementException, IOException { type = JPEG; originalType = ORIGINAL_JPEG; InputStream is = null; try { String errorID; if (rawData == null) { is = url.openStream(); errorID = url.toString(); } else { is = new java.io.ByteArrayInputStream(rawData); errorID = "Byte array"; } if (is.read() != 0xFF || is.read() != 0xD8) { throw new BadElementException(errorID + " is not a valid JPEG-file."); } boolean firstPass = true; int len; while (true) { int v = is.read(); if (v < 0) throw new IOException("Premature EOF while reading JPG."); if (v == 0xFF) { int marker = is.read(); if (firstPass && marker == M_APP0) { firstPass = false; len = getShort(is); if (len < 16) { Utilities.skip(is, len - 2); continue; } byte bcomp[] = new byte[JFIF_ID.length]; int r = is.read(bcomp); if (r != bcomp.length) throw new BadElementException(errorID + " corrupted JFIF marker."); boolean found = true; for (int k = 0; k < bcomp.length; ++k) { if (bcomp[k] != JFIF_ID[k]) { found = false; break; } } if (!found) { Utilities.skip(is, len - 2 - bcomp.length); continue; } Utilities.skip(is, 2); int units = is.read(); int dx = getShort(is); int dy = getShort(is); if (units == 1) { dpiX = dx; dpiY = dy; } else if (units == 2) { dpiX = (int) (dx * 2.54f + 0.5f); dpiY = (int) (dy * 2.54f + 0.5f); } Utilities.skip(is, len - 2 - bcomp.length - 7); continue; } if (marker == M_APPE) { len = getShort(is) - 2; byte[] byteappe = new byte[len]; for (int k = 0; k < len; ++k) { byteappe[k] = (byte) is.read(); } if (byteappe.length >= 12) { String appe = new String(byteappe, 0, 5, "ISO-8859-1"); if (appe.equals("Adobe")) { invert = true; } } continue; } if (marker == M_APP2) { len = getShort(is) - 2; byte[] byteapp2 = new byte[len]; for (int k = 0; k < len; ++k) { byteapp2[k] = (byte) is.read(); } if (byteapp2.length >= 14) { String app2 = new String(byteapp2, 0, 11, "ISO-8859-1"); if (app2.equals("ICC_PROFILE")) { int order = byteapp2[12] & 0xff; int count = byteapp2[13] & 0xff; if (icc == null) icc = new byte[count][]; icc[order - 1] = byteapp2; } } continue; } firstPass = false; int markertype = marker(marker); if (markertype == VALID_MARKER) { Utilities.skip(is, 2); if (is.read() != 0x08) { throw new BadElementException(errorID + " must have 8 bits per component."); } scaledHeight = getShort(is); setTop(scaledHeight); scaledWidth = getShort(is); setRight(scaledWidth); colorspace = is.read(); bpc = 8; break; } else if (markertype == UNSUPPORTED_MARKER) { throw new BadElementException(errorID + ": unsupported JPEG marker: " + marker); } else if (markertype != NOPARAM_MARKER) { Utilities.skip(is, getShort(is) - 2); } } } } finally { if (is != null) { is.close(); } } plainWidth = getWidth(); plainHeight = getHeight(); if (icc != null) { int total = 0; for (int k = 0; k < icc.length; ++k) { if (icc[k] == null) { icc = null; return; } total += icc[k].length - 14; } byte[] ficc = new byte[total]; total = 0; for (int k = 0; k < icc.length; ++k) { System.arraycopy(icc[k], 14, ficc, total, icc[k].length - 14); total += icc[k].length - 14; } try { ICC_Profile icc_prof = ICC_Profile.getInstance(ficc); tagICC(icc_prof); } catch (IllegalArgumentException e) { // ignore ICC profile if it's invalid. } icc = null; } } }