1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.awt.image;
27
28 import java.awt.color.ICC_Profile;
29 import java.awt.geom.Rectangle2D;
30 import java.awt.Rectangle;
31 import java.awt.RenderingHints;
32 import java.awt.geom.Point2D;
33 import java.lang.annotation.Native;
34 import sun.awt.image.ImagingLib;
35
36 /**
37 * This class implements a convolution from the source
38 * to the destination.
39 * Convolution using a convolution kernel is a spatial operation that
40 * computes the output pixel from an input pixel by multiplying the kernel
41 * with the surround of the input pixel.
42 * This allows the output pixel to be affected by the immediate neighborhood
43 * in a way that can be mathematically specified with a kernel.
44 *<p>
45 * This class operates with BufferedImage data in which color components are
46 * premultiplied with the alpha component. If the Source BufferedImage has
47 * an alpha component, and the color components are not premultiplied with
48 * the alpha component, then the data are premultiplied before being
49 * convolved. If the Destination has color components which are not
50 * premultiplied, then alpha is divided out before storing into the
51 * Destination (if alpha is 0, the color components are set to 0). If the
52 * Destination has no alpha component, then the resulting alpha is discarded
53 * after first dividing it out of the color components.
54 * <p>
55 * Rasters are treated as having no alpha channel. If the above treatment
56 * of the alpha channel in BufferedImages is not desired, it may be avoided
57 * by getting the Raster of a source BufferedImage and using the filter method
58 * of this class which works with Rasters.
59 * <p>
60 * If a RenderingHints object is specified in the constructor, the
61 * color rendering hint and the dithering hint may be used when color
62 * conversion is required.
63 *<p>
64 * Note that the Source and the Destination may not be the same object.
65 * @see Kernel
66 * @see java.awt.RenderingHints#KEY_COLOR_RENDERING
67 * @see java.awt.RenderingHints#KEY_DITHERING
68 */
69 public class ConvolveOp implements BufferedImageOp, RasterOp {
70 Kernel kernel;
71 int edgeHint;
72 RenderingHints hints;
73 /**
74 * Edge condition constants.
75 */
76
77 /**
78 * Pixels at the edge of the destination image are set to zero. This
79 * is the default.
80 */
81
82 @Native public static final int EDGE_ZERO_FILL = 0;
83
84 /**
85 * Pixels at the edge of the source image are copied to
86 * the corresponding pixels in the destination without modification.
87 */
88 @Native public static final int EDGE_NO_OP = 1;
89
90 /**
91 * Constructs a ConvolveOp given a Kernel, an edge condition, and a
92 * RenderingHints object (which may be null).
93 * @param kernel the specified <code>Kernel</code>
94 * @param edgeCondition the specified edge condition
95 * @param hints the specified <code>RenderingHints</code> object
96 * @see Kernel
97 * @see #EDGE_NO_OP
98 * @see #EDGE_ZERO_FILL
99 * @see java.awt.RenderingHints
100 */
101 public ConvolveOp(Kernel kernel, int edgeCondition, RenderingHints hints) {
102 this.kernel = kernel;
103 this.edgeHint = edgeCondition;
104 this.hints = hints;
105 }
106
107 /**
108 * Constructs a ConvolveOp given a Kernel. The edge condition
109 * will be EDGE_ZERO_FILL.
110 * @param kernel the specified <code>Kernel</code>
111 * @see Kernel
112 * @see #EDGE_ZERO_FILL
113 */
114 public ConvolveOp(Kernel kernel) {
115 this.kernel = kernel;
116 this.edgeHint = EDGE_ZERO_FILL;
117 }
118
119 /**
120 * Returns the edge condition.
121 * @return the edge condition of this <code>ConvolveOp</code>.
122 * @see #EDGE_NO_OP
123 * @see #EDGE_ZERO_FILL
124 */
125 public int getEdgeCondition() {
126 return edgeHint;
127 }
128
129 /**
130 * Returns the Kernel.
131 * @return the <code>Kernel</code> of this <code>ConvolveOp</code>.
132 */
133 public final Kernel getKernel() {
134 return (Kernel) kernel.clone();
135 }
136
137 /**
138 * Performs a convolution on BufferedImages. Each component of the
139 * source image will be convolved (including the alpha component, if
140 * present).
141 * If the color model in the source image is not the same as that
142 * in the destination image, the pixels will be converted
143 * in the destination. If the destination image is null,
144 * a BufferedImage will be created with the source ColorModel.
145 * The IllegalArgumentException may be thrown if the source is the
146 * same as the destination.
147 * @param src the source <code>BufferedImage</code> to filter
148 * @param dst the destination <code>BufferedImage</code> for the
149 * filtered <code>src</code>
150 * @return the filtered <code>BufferedImage</code>
151 * @throws NullPointerException if <code>src</code> is <code>null</code>
152 * @throws IllegalArgumentException if <code>src</code> equals
153 * <code>dst</code>
154 * @throws ImagingOpException if <code>src</code> cannot be filtered
155 */
156 public final BufferedImage filter (BufferedImage src, BufferedImage dst) {
157 if (src == null) {
158 throw new NullPointerException("src image is null");
159 }
160 if (src == dst) {
161 throw new IllegalArgumentException("src image cannot be the "+
162 "same as the dst image");
163 }
164
165 boolean needToConvert = false;
166 ColorModel srcCM = src.getColorModel();
167 ColorModel dstCM;
168 BufferedImage origDst = dst;
169
170 // Can't convolve an IndexColorModel. Need to expand it
171 if (srcCM instanceof IndexColorModel) {
172 IndexColorModel icm = (IndexColorModel) srcCM;
173 src = icm.convertToIntDiscrete(src.getRaster(), false);
174 srcCM = src.getColorModel();
175 }
176
177 if (dst == null) {
178 dst = createCompatibleDestImage(src, null);
179 dstCM = srcCM;
180 origDst = dst;
181 }
182 else {
183 dstCM = dst.getColorModel();
184 if (srcCM.getColorSpace().getType() !=
185 dstCM.getColorSpace().getType())
186 {
187 needToConvert = true;
188 dst = createCompatibleDestImage(src, null);
189 dstCM = dst.getColorModel();
190 }
191 else if (dstCM instanceof IndexColorModel) {
192 dst = createCompatibleDestImage(src, null);
193 dstCM = dst.getColorModel();
194 }
195 }
196
197 if (ImagingLib.filter(this, src, dst) == null) {
198 throw new ImagingOpException ("Unable to convolve src image");
199 }
200
201 if (needToConvert) {
202 ColorConvertOp ccop = new ColorConvertOp(hints);
203 ccop.filter(dst, origDst);
204 }
205 else if (origDst != dst) {
206 java.awt.Graphics2D g = origDst.createGraphics();
207 try {
208 g.drawImage(dst, 0, 0, null);
209 } finally {
210 g.dispose();
211 }
212 }
213
214 return origDst;
215 }
216
217 /**
218 * Performs a convolution on Rasters. Each band of the source Raster
219 * will be convolved.
220 * The source and destination must have the same number of bands.
221 * If the destination Raster is null, a new Raster will be created.
222 * The IllegalArgumentException may be thrown if the source is
223 * the same as the destination.
224 * @param src the source <code>Raster</code> to filter
225 * @param dst the destination <code>WritableRaster</code> for the
226 * filtered <code>src</code>
227 * @return the filtered <code>WritableRaster</code>
228 * @throws NullPointerException if <code>src</code> is <code>null</code>
229 * @throws ImagingOpException if <code>src</code> and <code>dst</code>
230 * do not have the same number of bands
231 * @throws ImagingOpException if <code>src</code> cannot be filtered
232 * @throws IllegalArgumentException if <code>src</code> equals
233 * <code>dst</code>
234 */
235 public final WritableRaster filter (Raster src, WritableRaster dst) {
236 if (dst == null) {
237 dst = createCompatibleDestRaster(src);
238 }
239 else if (src == dst) {
240 throw new IllegalArgumentException("src image cannot be the "+
241 "same as the dst image");
242 }
243 else if (src.getNumBands() != dst.getNumBands()) {
244 throw new ImagingOpException("Different number of bands in src "+
245 " and dst Rasters");
246 }
247
248 if (ImagingLib.filter(this, src, dst) == null) {
249 throw new ImagingOpException ("Unable to convolve src image");
250 }
251
252 return dst;
253 }
254
255 /**
256 * Creates a zeroed destination image with the correct size and number
257 * of bands. If destCM is null, an appropriate ColorModel will be used.
258 * @param src Source image for the filter operation.
259 * @param destCM ColorModel of the destination. Can be null.
260 * @return a destination <code>BufferedImage</code> with the correct
261 * size and number of bands.
262 */
263 public BufferedImage createCompatibleDestImage(BufferedImage src,
264 ColorModel destCM) {
265 BufferedImage image;
266
267 int w = src.getWidth();
268 int h = src.getHeight();
269
270 WritableRaster wr = null;
271
272 if (destCM == null) {
273 destCM = src.getColorModel();
274 // Not much support for ICM
275 if (destCM instanceof IndexColorModel) {
276 destCM = ColorModel.getRGBdefault();
277 } else {
278 /* Create destination image as similar to the source
279 * as it possible...
280 */
281 wr = src.getData().createCompatibleWritableRaster(w, h);
282 }
283 }
284
285 if (wr == null) {
286 /* This is the case when destination color model
287 * was explicitly specified (and it may be not compatible
288 * with source raster structure) or source is indexed image.
289 * We should use destination color model to create compatible
290 * destination raster here.
291 */
292 wr = destCM.createCompatibleWritableRaster(w, h);
293 }
294
295 image = new BufferedImage (destCM, wr,
296 destCM.isAlphaPremultiplied(), null);
297
298 return image;
299 }
300
301 /**
302 * Creates a zeroed destination Raster with the correct size and number
303 * of bands, given this source.
304 */
305 public WritableRaster createCompatibleDestRaster(Raster src) {
306 return src.createCompatibleWritableRaster();
307 }
308
309 /**
310 * Returns the bounding box of the filtered destination image. Since
311 * this is not a geometric operation, the bounding box does not
312 * change.
313 */
314 public final Rectangle2D getBounds2D(BufferedImage src) {
315 return getBounds2D(src.getRaster());
316 }
317
318 /**
319 * Returns the bounding box of the filtered destination Raster. Since
320 * this is not a geometric operation, the bounding box does not
321 * change.
322 */
323 public final Rectangle2D getBounds2D(Raster src) {
324 return src.getBounds();
325 }
326
327 /**
328 * Returns the location of the destination point given a
329 * point in the source. If dstPt is non-null, it will
330 * be used to hold the return value. Since this is not a geometric
331 * operation, the srcPt will equal the dstPt.
332 */
333 public final Point2D getPoint2D(Point2D srcPt, Point2D dstPt) {
334 if (dstPt == null) {
335 dstPt = new Point2D.Float();
336 }
337 dstPt.setLocation(srcPt.getX(), srcPt.getY());
338
339 return dstPt;
340 }
341
342 /**
343 * Returns the rendering hints for this op.
344 */
345 public final RenderingHints getRenderingHints() {
346 return hints;
347 }
348 }