1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.pdfbox.pdmodel.graphics.xobject;
18
19 import java.io.IOException;
20 import java.util.List;
21
22 import org.apache.pdfbox.cos.COSBase;
23 import org.apache.pdfbox.cos.COSName;
24 import org.apache.pdfbox.cos.COSStream;
25
26 import org.apache.pdfbox.pdmodel.PDDocument;
27 import org.apache.pdfbox.pdmodel.common.COSObjectable;
28 import org.apache.pdfbox.pdmodel.common.PDMetadata;
29 import org.apache.pdfbox.pdmodel.common.PDStream;
30
31 /**
32 * The base class for all XObjects in the PDF document.
33 *
34 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
35 * @author mathiak
36 * @author Marcel Kammer
37 * @version $Revision: 1.14 $
38 */
39 public abstract class PDXObject implements COSObjectable
40 {
41 private PDStream xobject;
42
43 /**
44 * Standard constuctor.
45 *
46 * @param xobj The XObject dictionary.
47 */
48 public PDXObject(COSStream xobj)
49 {
50 xobject = new PDStream( xobj );
51 xobject.getStream().setName( COSName.TYPE, "XObject" );
52 }
53
54 /**
55 * Standard constuctor.
56 *
57 * @param xobj The XObject dictionary.
58 */
59 public PDXObject(PDStream xobj)
60 {
61 xobject = xobj;
62 xobject.getStream().setName( COSName.TYPE, "XObject" );
63 }
64
65 /**
66 * Standard constuctor.
67 *
68 * @param doc The doc to store the object contents.
69 */
70 public PDXObject(PDDocument doc)
71 {
72 xobject = new PDStream(doc);
73 xobject.getStream().setName( COSName.TYPE, "XObject" );
74 }
75
76 /**
77 * Returns the stream.
78 *
79 * {@inheritDoc}
80 */
81 public COSBase getCOSObject()
82 {
83 return xobject.getCOSObject();
84 }
85
86 /**
87 * Returns the stream.
88 * @return The stream for this object.
89 */
90 public COSStream getCOSStream()
91 {
92 return xobject.getStream();
93 }
94
95 /**
96 * Returns the stream.
97 * @return The stream for this object.
98 */
99 public PDStream getPDStream()
100 {
101 return xobject;
102 }
103
104 /**
105 * Create the correct xobject from the cos base.
106 *
107 * @param xobject The cos level xobject to create.
108 *
109 * @return a pdmodel xobject
110 * @throws IOException If there is an error creating the xobject.
111 */
112 public static PDXObject createXObject( COSBase xobject ) throws IOException
113 {
114 PDXObject retval = null;
115 if( xobject == null )
116 {
117 retval = null;
118 }
119 else if( xobject instanceof COSStream )
120 {
121 COSStream xstream = (COSStream)xobject;
122 String subtype = xstream.getNameAsString( "Subtype" );
123 if( subtype.equals( PDXObjectImage.SUB_TYPE ) )
124 {
125 PDStream image = new PDStream( xstream );
126 // See if filters are DCT or JPX otherwise treat as Bitmap-like
127 // There might be a problem with several filters, but that's ToDo until
128 // I find an example
129 List filters = image.getFilters();
130 if( filters != null && filters.contains( COSName.DCT_DECODE.getName() ) )
131 {
132 return new PDJpeg(image);
133 }
134 else if ( filters != null && filters.contains( COSName.CCITTFAX_DECODE.getName() ) )
135 {
136 return new PDCcitt(image);
137 }
138 else if( filters != null && filters.contains(COSName.JPX_DECODE.getName()))
139 {
140 //throw new IOException( "JPXDecode has not been implemented for images" );
141 //JPX Decode is not really supported right now, but if we are just doing
142 //text extraction then we don't want to throw an exception, so for now
143 //just return a PDPixelMap, which will break later on if it is
144 //actually used, but for text extraction it is not used.
145
146 return new PDPixelMap( image );
147
148 }
149 /*else if( filters != null && filters.contains(COSName.FLATE_DECODE.getName()))
150 {
151 retval = new PDPixelMap(image);
152 }*/
153 else
154 {
155 retval = new PDPixelMap(image);
156 //throw new IOException ("Default branch: filters = " + filters.toString());
157 }
158 }
159 else if( subtype.equals( PDXObjectForm.SUB_TYPE ) )
160 {
161 retval = new PDXObjectForm( xstream );
162 }
163 else
164 {
165 throw new IOException( "Unknown xobject subtype '" + subtype + "'" );
166 }
167 }
168 else
169 {
170 throw new IOException( "Unknown xobject type:" + xobject.getClass().getName() );
171 }
172
173 return retval;
174 }
175
176 /**
177 * Get the metadata that is part of the document catalog. This will
178 * return null if there is no meta data for this object.
179 *
180 * @return The metadata for this object.
181 */
182 public PDMetadata getMetadata()
183 {
184 PDMetadata retval = null;
185 COSStream mdStream = (COSStream)xobject.getStream().getDictionaryObject( "Metadata" );
186 if( mdStream != null )
187 {
188 retval = new PDMetadata( mdStream );
189 }
190 return retval;
191 }
192
193 /**
194 * Set the metadata for this object. This can be null.
195 *
196 * @param meta The meta data for this object.
197 */
198 public void setMetadata( PDMetadata meta )
199 {
200 xobject.getStream().setItem( "Metadata", meta );
201 }
202 }