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comparison common/src/main/java/digilib/image/JAIImageLoaderDocuImage.java @ 903:7779b37d1d05

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refactored into maven modules per servlet type. can build servlet-api 2.3 and 3.0 via profile now!
author robcast
date Tue, 26 Apr 2011 20:24:31 +0200
parents servlet/src/main/java/digilib/image/JAIImageLoaderDocuImage.java@ba1eb2d821a2
children 28d007673346
comparison
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902:89ba3ffcf552 903:7779b37d1d05
1 /* JAIImageLoaderDocuImage -- Image class implementation using JAI's ImageLoader Plugin
2
3 Digital Image Library servlet components
4
5 Copyright (C) 2002, 2003 Robert Casties (robcast@mail.berlios.de)
6
7 This program is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 2 of the License, or (at your
10 option) any later version.
11
12 Please read license.txt for the full details. A copy of the GPL
13 may be found at http://www.gnu.org/copyleft/lgpl.html
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
19 */
20
21 package digilib.image;
22
23 import java.awt.Image;
24 import java.awt.Rectangle;
25 import java.awt.image.renderable.ParameterBlock;
26 import java.io.File;
27 import java.io.IOException;
28 import java.io.OutputStream;
29 import java.io.RandomAccessFile;
30 import java.util.Iterator;
31
32 import javax.imageio.ImageIO;
33 import javax.imageio.ImageReadParam;
34 import javax.imageio.ImageReader;
35 import javax.imageio.stream.FileImageInputStream;
36 import javax.imageio.stream.ImageInputStream;
37 import javax.media.jai.JAI;
38 import javax.servlet.ServletException;
39
40 import digilib.io.FileOpException;
41 import digilib.io.ImageInput;
42 import digilib.util.ImageSize;
43
44 /** DocuImage implementation using the Java Advanced Imaging API and the ImageLoader
45 * API of Java 1.4.
46 */
47 public class JAIImageLoaderDocuImage extends JAIDocuImage {
48
49 /** ImageIO image reader */
50 protected ImageReader reader;
51 /** current image file */
52 protected File imgFile;
53
54 /* loadSubimage is supported. */
55 public boolean isSubimageSupported() {
56 return true;
57 }
58
59 /* returns the size of the current image */
60 public ImageSize getSize() {
61 ImageSize is = null;
62 // TODO: can we cache imageSize?
63 int h = 0;
64 int w = 0;
65 try {
66 if (img == null) {
67 // get size from ImageReader
68 h = reader.getHeight(0);
69 w = reader.getWidth(0);
70 } else {
71 // get size from image
72 h = img.getHeight();
73 w = img.getWidth();
74 }
75 is = new ImageSize(w, h);
76 } catch (IOException e) {
77 logger.debug("error in getSize:", e);
78 }
79 return is;
80 }
81
82
83 /* Load an image file into the Object. */
84 public void loadImage(ImageInput ii) throws FileOpException {
85 logger.debug("loadImage: "+ii);
86 if (ii.hasImageInputStream()) {
87 img = JAI.create("ImageRead", ii.getImageInputStream());
88 } else if (ii.hasFile()) {
89 img = JAI.create("ImageRead", ii.getFile().getAbsolutePath());
90 }
91 if (img == null) {
92 throw new FileOpException("Unable to load File!");
93 }
94 }
95
96 /* Get an ImageReader for the image file. */
97 public ImageReader getReader(ImageInput input) throws IOException {
98 logger.debug("get ImageReader for " + input);
99 if (this.reader != null) {
100 if (this.input == input) {
101 // it was the same input
102 logger.debug("reusing Reader");
103 return reader;
104 }
105 // clean up old reader
106 logger.debug("cleaning Reader!");
107 dispose();
108 }
109 this.input = input;
110 ImageInputStream istream = null;
111 if (input.hasImageInputStream()) {
112 // stream input
113 istream = input.getImageInputStream();
114 } else if (input.hasFile()) {
115 // file only input
116 RandomAccessFile rf = new RandomAccessFile(input.getFile(), "r");
117 istream = new FileImageInputStream(rf);
118 } else {
119 throw new FileOpException("Unable to get data from ImageInput");
120 }
121 Iterator<ImageReader> readers;
122 String mt = input.getMimetype();
123 if (mt == null) {
124 logger.debug("No mime-type. Trying automagic.");
125 readers = ImageIO.getImageReaders(istream);
126 } else {
127 logger.debug("File type:" + mt);
128 readers = ImageIO.getImageReadersByMIMEType(mt);
129 }
130 if (!readers.hasNext()) {
131 throw new FileOpException("Can't find Reader to load File!");
132 }
133 reader = readers.next();
134 logger.debug("ImageIO: this reader: " + reader.getClass());
135 /* are there more readers? */
136 /* while (readers.hasNext()) {
137 logger.debug("ImageIO: next reader: " + readers.next().getClass());
138 } */
139 reader.setInput(istream);
140 return reader;
141 }
142
143 /* Load an image file into the Object. */
144 public void loadSubimage(ImageInput ii, Rectangle region, int prescale)
145 throws FileOpException {
146 logger.debug("loadSubimage: "+ii.getFile());
147 //System.gc();
148 try {
149 if ((reader == null) || (imgFile != ii.getFile())) {
150 getReader(ii);
151 }
152 ImageReadParam readParam = reader.getDefaultReadParam();
153 readParam.setSourceRegion(region);
154 readParam.setSourceSubsampling(prescale, prescale, 0, 0);
155 img = reader.read(0, readParam);
156 /* JAI imageread seems to ignore the readParam :-(
157 ImageInputStream istream = (ImageInputStream) reader.getInput();
158 ParameterBlockJAI pb = new ParameterBlockJAI("imageread");
159 pb.setParameter("Input", istream);
160 pb.setParameter("ReadParam", readParam);
161 pb.setParameter("Reader", reader);
162 img = JAI.create("imageread", pb);
163 */
164 } catch (IOException e) {
165 throw new FileOpException("Unable to load File!");
166 }
167 if (img == null) {
168 throw new FileOpException("Unable to load File!");
169 }
170 imgFile = ii.getFile();
171 }
172
173
174 /* Write the current image to an OutputStream. */
175 public void writeImage(String mt, OutputStream ostream)
176 throws ImageOpException, ServletException {
177 logger.debug("writeImage");
178 try {
179 // setup output
180 ParameterBlock pb3 = new ParameterBlock();
181 pb3.addSource(img);
182 pb3.add(ostream);
183 if (mt == "image/jpeg") {
184 pb3.add("JPEG");
185 } else if (mt == "image/png") {
186 pb3.add("PNG");
187 } else {
188 // unknown mime type
189 throw new ImageOpException("Unknown mime type: " + mt);
190 }
191 // render output
192 JAI.create("ImageWrite", pb3);
193 } catch (RuntimeException e) {
194 throw new ServletException("Error writing image.");
195 }
196 }
197
198 @Override
199 public Image getAwtImage() {
200 // TODO Auto-generated method stub
201 return (Image) img;
202 }
203
204 /* (non-Javadoc)
205 * @see java.lang.Object#finalize()
206 */
207 protected void finalize() throws Throwable {
208 dispose();
209 super.finalize();
210 }
211
212 public void dispose() {
213 // we must dispose the ImageReader because it keeps the filehandle open!
214 reader.dispose();
215 reader = null;
216 img = null;
217 }
218
219 }