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1
24 package org.riotfamily.common.image;
25
26 import java.awt.Graphics2D  ;
27 import java.awt.RenderingHints ;
28 import java.awt.image.BufferedImage ;
29 import java.awt.image.RenderedImage ;
30 import java.io.File ;
31 import java.io.FileInputStream ;
32 import java.io.IOException ;
33 import java.io.InputStream ;
34 import java.util.Iterator ;
35 import java.util.Locale ;
36
37 import javax.imageio.IIOImage ;
38 import javax.imageio.ImageIO ;
39 import javax.imageio.ImageWriteParam ;
40 import javax.imageio.ImageWriter ;
41 import javax.imageio.plugins.jpeg.JPEGImageWriteParam ;
42 import javax.imageio.stream.ImageOutputStream ;
43
44 import org.riotfamily.common.util.FormatUtils;
45 import org.springframework.util.Assert;
46
47
52 public class ImageIOThumbnailer implements Thumbnailer {
53
54 static {
55 System.setProperty("java.awt.headless", "true");
56 }
57
58 private static final String FORMAT_JPG = "jpg";
59
60 private static final String FORMAT_PNG = "png";
61
62 private int maxCrop = 0;
63
64 public void setMaxCrop(int maxCrop) {
65 this.maxCrop = maxCrop;
66 }
67
68 public void renderThumbnail(File source, File dest, int width, int height)
69 throws IOException {
70
71 BufferedImage originalImage = readImage(new FileInputStream (source));
72 boolean alpha = originalImage.getColorModel().hasAlpha();
73
74 int imageWidth = originalImage.getWidth(null);
75 int imageHeight = originalImage.getHeight(null);
76
77 int thumbWidth;
78 int thumbHeight;
79
80 double scaleX = (double) width / (double) imageWidth;
81 double scaleY = (double) height / (double) imageHeight;
82
83 double scale = Math.min(Math.max(scaleX, scaleY), 1);
84 thumbWidth = (int) (imageWidth * scale);
85 thumbHeight = (int) (imageHeight * scale);
86 double cropFactor = (double) maxCrop / 100;
87
88 if ((thumbWidth - width > cropFactor * thumbWidth)
89 || (thumbHeight - height > cropFactor * thumbHeight)) {
90
91 scaleX = width / (imageWidth - cropFactor * imageWidth);
92 scaleY = height / (imageHeight - cropFactor * imageHeight);
93 scale = Math.min(Math.min(scaleX, scaleY), 1);
94 }
95
96 thumbWidth = (int) (imageWidth * scale);
97 thumbHeight = (int) (imageHeight * scale);
98
99 BufferedImage thumbImage = new BufferedImage (thumbWidth,
100 thumbHeight, alpha
101 ? BufferedImage.TYPE_INT_ARGB
102 : BufferedImage.TYPE_INT_RGB);
103
104 Graphics2D graphics2D = thumbImage.createGraphics();
105 graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
106 RenderingHints.VALUE_INTERPOLATION_BICUBIC);
107
108 graphics2D.drawImage(originalImage, 0, 0, thumbWidth, thumbHeight, null);
109
110 int x = Math.max((thumbWidth - width) / 2, 0);
111 int y = Math.max((thumbHeight - height) / 2, 0);
112 if (x > 0 || y > 0) {
113 thumbWidth = Math.min(thumbWidth, width);
114 thumbHeight = Math.min(thumbHeight, height);
115 thumbImage = thumbImage.getSubimage(x, y, thumbWidth, thumbHeight);
116 }
117
118 writeImage(thumbImage, dest);
119 }
120
121 private BufferedImage readImage(InputStream in) throws IOException {
122 try {
123 return ImageIO.read(in);
124 }
125 finally {
126 try {
127 in.close();
128 }
129 catch (Exception e) {
130 }
131 }
132 }
133
134 private void writeImage(RenderedImage im, File dest) throws IOException {
135 ImageWriter writer = null;
136 ImageOutputStream ios = null;
137 try {
138 String formatName = FormatUtils.getExtension(dest.getName()).toLowerCase();
139 if (!formatName.equals(FORMAT_JPG) && !formatName.equals(FORMAT_PNG)) {
140 formatName = FORMAT_JPG;
141 }
142 Iterator it = ImageIO.getImageWritersByFormatName(formatName);
143 if (it.hasNext()) {
144 writer = (ImageWriter ) it.next();
145 }
146 Assert.notNull(writer, "No ImageWriter available for format "
147 + formatName);
148
149 ios = ImageIO.createImageOutputStream(dest);
150 writer.setOutput(ios);
151
152 ImageWriteParam iwparam = null;
153
154 if (formatName.equals(FORMAT_JPG)) {
155 iwparam = new JPEGImageWriteParam (Locale.getDefault());
156 iwparam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
157 iwparam.setCompressionQuality(1);
158 }
159
160 writer.write(null, new IIOImage (im, null, null), iwparam);
161 ios.flush();
162 }
163 finally {
164 if (writer != null) {
165 writer.dispose();
166 }
167 if (ios != null) {
168 ios.close();
169 }
170 }
171 }
172
173 }
174 |
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