1 /*
2  * $Id$
3  *
4  * Copyright 2009 by Nigel Kerr.
5  *
6  * The contents of this file are subject to the Mozilla Public License Version 1.1
7  * (the "License"); you may not use this file except in compliance with the License.
8  * You may obtain a copy of the License at http://www.mozilla.org/MPL/
9  *
10  * Software distributed under the License is distributed on an "AS IS" basis,
11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12  * for the specific language governing rights and limitations under the License.
13  *
14  * The Original Code is 'iText, a free JAVA-PDF library'.
15  *
16  * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
17  * the Initial Developer are Copyright (C) 1999-2009 by Bruno Lowagie.
18  * All Rights Reserved.
19  * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
20  * are Copyright (C) 2000-2009 by Paulo Soares. All Rights Reserved.
21  *
22  * Contributor(s): all the names of the contributors are added in the source code
23  * where applicable.
24  *
25  * Alternatively, the contents of this file may be used under the terms of the
26  * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
27  * provisions of LGPL are applicable instead of those above.  If you wish to
28  * allow use of your version of this file only under the terms of the LGPL
29  * License and not to allow others to use your version of this file under
30  * the MPL, indicate your decision by deleting the provisions above and
31  * replace them with the notice and other provisions required by the LGPL.
32  * If you do not delete the provisions above, a recipient may use your version
33  * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
34  *
35  * This library is free software; you can redistribute it and/or modify it
36  * under the terms of the MPL as stated above or under the terms of the GNU
37  * Library General Public License as published by the Free Software Foundation;
38  * either version 2 of the License, or any later version.
39  *
40  * This library is distributed in the hope that it will be useful, but WITHOUT
41  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
42  * FOR A PARTICULAR PURPOSE. See the GNU Library general Public License for more
43  * details.
44  *
45  * If you didn't download this code from the following link, you should check if
46  * you aren't using an obsolete version:
47  * http://www.lowagie.com/iText/
48  */
49 
50 package com.lowagie.text.pdf.codec;
51 
52 import com.lowagie.text.ExceptionConverter;
53 import com.lowagie.text.Image;
54 import com.lowagie.text.ImgJBIG2;
55 import com.lowagie.text.pdf.RandomAccessFileOrArray;
56 import com.lowagie.text.error_messages.MessageLocalization;
57 
58 /**
59  * Support for JBIG2 Images.
60  * This class assumes that we are always embedding into a pdf.
61  *
62  * @since 2.1.5
63  */
64 public class JBIG2Image {
65 
66 	/**
67 	 * Gets a byte array that can be used as a /JBIG2Globals,
68 	 * or null if not applicable to the given jbig2.
69 	 * @param	ra	an random access file or array
70 	 * @return	a byte array
71 	 */
getGlobalSegment(RandomAccessFileOrArray ra )72 	public static byte[] getGlobalSegment(RandomAccessFileOrArray ra ) {
73 		try {
74 			JBIG2SegmentReader sr = new JBIG2SegmentReader(ra);
75 			sr.read();
76 			return sr.getGlobal(true);
77 		} catch (Exception e) {
78 	        return null;
79 	    }
80 	}
81 
82 	/**
83 	 * returns an Image representing the given page.
84 	 * @param ra	the file or array containing the image
85 	 * @param page	the page number of the image
86 	 * @return	an Image object
87 	 */
getJbig2Image(RandomAccessFileOrArray ra, int page)88 	public static Image getJbig2Image(RandomAccessFileOrArray ra, int page) {
89 		if (page < 1)
90             throw new IllegalArgumentException(MessageLocalization.getComposedMessage("the.page.number.must.be.gt.eq.1"));
91 
92 		try {
93 			JBIG2SegmentReader sr = new JBIG2SegmentReader(ra);
94 			sr.read();
95 			JBIG2SegmentReader.JBIG2Page p = sr.getPage(page);
96 			Image img = new ImgJBIG2(p.pageBitmapWidth, p.pageBitmapHeight, p.getData(true), sr.getGlobal(true));
97 			return img;
98 		} catch (Exception e) {
99 	        throw new ExceptionConverter(e);
100 	    }
101 	}
102 
103 	/***
104 	 * Gets the number of pages in a JBIG2 image.
105 	 * @param ra	a random acces file array containing a JBIG2 image
106 	 * @return	the number of pages
107 	 */
getNumberOfPages(RandomAccessFileOrArray ra)108 	public static int getNumberOfPages(RandomAccessFileOrArray ra) {
109 		try {
110 			JBIG2SegmentReader sr = new JBIG2SegmentReader(ra);
111 			sr.read();
112 			return sr.numberOfPages();
113 		} catch (Exception e) {
114 	        throw new ExceptionConverter(e);
115 	    }
116     }
117 
118 
119 }
120