001/*
002 * $Id: JBIG2Image.java 4784 2011-03-15 08:33:00Z blowagie $
003 *
004 * This file is part of the iText (R) project.
005 * Copyright (c) 1998-2011 1T3XT BVBA
006 * Authors: Bruno Lowagie, Paulo Soares, et al.
007 *
008 * This program is free software; you can redistribute it and/or modify
009 * it under the terms of the GNU Affero General Public License version 3
010 * as published by the Free Software Foundation with the addition of the
011 * following permission added to Section 15 as permitted in Section 7(a):
012 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
013 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
014 *
015 * This program is distributed in the hope that it will be useful, but
016 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
017 * or FITNESS FOR A PARTICULAR PURPOSE.
018 * See the GNU Affero General Public License for more details.
019 * You should have received a copy of the GNU Affero General Public License
020 * along with this program; if not, see http://www.gnu.org/licenses or write to
021 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
022 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
023 * http://itextpdf.com/terms-of-use/
024 *
025 * The interactive user interfaces in modified source and object code versions
026 * of this program must display Appropriate Legal Notices, as required under
027 * Section 5 of the GNU Affero General Public License.
028 *
029 * In accordance with Section 7(b) of the GNU Affero General Public License,
030 * a covered work must retain the producer line in every PDF that is created
031 * or manipulated using iText.
032 *
033 * You can be released from the requirements of the license by purchasing
034 * a commercial license. Buying such a license is mandatory as soon as you
035 * develop commercial activities involving the iText software without
036 * disclosing the source code of your own applications.
037 * These activities include: offering paid services to customers as an ASP,
038 * serving PDFs on the fly in a web application, shipping iText with a closed
039 * source product.
040 *
041 * For more information, please contact iText Software Corp. at this
042 * address: sales@itextpdf.com
043 */
044package com.itextpdf.text.pdf.codec;
045
046import com.itextpdf.text.ExceptionConverter;
047import com.itextpdf.text.Image;
048import com.itextpdf.text.ImgJBIG2;
049import com.itextpdf.text.pdf.RandomAccessFileOrArray;
050import com.itextpdf.text.error_messages.MessageLocalization;
051
052/**
053 * Support for JBIG2 Images.
054 * This class assumes that we are always embedding into a pdf.
055 * 
056 * @since 2.1.5
057 */
058public class JBIG2Image {
059
060        /**
061         * Gets a byte array that can be used as a /JBIG2Globals,
062         * or null if not applicable to the given jbig2.
063         * @param       ra      an random access file or array
064         * @return      a byte array
065         */
066        public static byte[] getGlobalSegment(RandomAccessFileOrArray ra ) {
067                try {
068                        JBIG2SegmentReader sr = new JBIG2SegmentReader(ra);
069                        sr.read();
070                        return sr.getGlobal(true);
071                } catch (Exception e) {
072                return null;
073            }
074        }
075        
076        /**
077         * returns an Image representing the given page.
078         * @param ra    the file or array containing the image
079         * @param page  the page number of the image
080         * @return      an Image object
081         */
082        public static Image getJbig2Image(RandomAccessFileOrArray ra, int page) {
083                if (page < 1)
084            throw new IllegalArgumentException(MessageLocalization.getComposedMessage("the.page.number.must.be.gt.eq.1"));
085                
086                try {
087                        JBIG2SegmentReader sr = new JBIG2SegmentReader(ra);
088                        sr.read();
089                        JBIG2SegmentReader.JBIG2Page p = sr.getPage(page);
090                        Image img = new ImgJBIG2(p.pageBitmapWidth, p.pageBitmapHeight, p.getData(true), sr.getGlobal(true));
091                        return img;
092                } catch (Exception e) {
093                throw new ExceptionConverter(e);
094            }
095        }
096
097        /***
098         * Gets the number of pages in a JBIG2 image.
099         * @param ra    a random acces file array containing a JBIG2 image
100         * @return      the number of pages
101         */
102        public static int getNumberOfPages(RandomAccessFileOrArray ra) {
103                try {
104                        JBIG2SegmentReader sr = new JBIG2SegmentReader(ra);
105                        sr.read();
106                        return sr.numberOfPages();
107                } catch (Exception e) {
108                throw new ExceptionConverter(e);
109            }
110    }
111        
112        
113}