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.geom.AffineTransform;
29 import java.awt.geom.NoninvertibleTransformException;
30 import java.awt.geom.Rectangle2D;
31 import java.awt.geom.Point2D;
32 import java.awt.AlphaComposite;
33 import java.awt.GraphicsEnvironment;
34 import java.awt.Rectangle;
35 import java.awt.RenderingHints;
36 import java.awt.Transparency;
37 import java.lang.annotation.Native;
38 import sun.awt.image.ImagingLib;
39
40 /**
41 * This class uses an affine transform to perform a linear mapping from
42 * 2D coordinates in the source image or <CODE>Raster</CODE> to 2D coordinates
43 * in the destination image or <CODE>Raster</CODE>.
44 * The type of interpolation that is used is specified through a constructor,
45 * either by a <CODE>RenderingHints</CODE> object or by one of the integer
46 * interpolation types defined in this class.
47 * <p>
48 * If a <CODE>RenderingHints</CODE> object is specified in the constructor, the
49 * interpolation hint and the rendering quality hint are used to set
50 * the interpolation type for this operation. The color rendering hint
51 * and the dithering hint can be used when color conversion is required.
52 * <p>
53 * Note that the following constraints have to be met:
54 * <ul>
55 * <li>The source and destination must be different.
56 * <li>For <CODE>Raster</CODE> objects, the number of bands in the source must
57 * be equal to the number of bands in the destination.
58 * </ul>
59 * @see AffineTransform
60 * @see BufferedImageFilter
61 * @see java.awt.RenderingHints#KEY_INTERPOLATION
62 * @see java.awt.RenderingHints#KEY_RENDERING
63 * @see java.awt.RenderingHints#KEY_COLOR_RENDERING
64 * @see java.awt.RenderingHints#KEY_DITHERING
65 */
66 public class AffineTransformOp implements BufferedImageOp, RasterOp {
67 private AffineTransform xform;
68 RenderingHints hints;
69
70 /**
71 * Nearest-neighbor interpolation type.
72 */
73 @Native public static final int TYPE_NEAREST_NEIGHBOR = 1;
74
75 /**
76 * Bilinear interpolation type.
77 */
78 @Native public static final int TYPE_BILINEAR = 2;
79
80 /**
81 * Bicubic interpolation type.
82 */
83 @Native public static final int TYPE_BICUBIC = 3;
84
85 int interpolationType = TYPE_NEAREST_NEIGHBOR;
86
87 /**
88 * Constructs an <CODE>AffineTransformOp</CODE> given an affine transform.
89 * The interpolation type is determined from the
90 * <CODE>RenderingHints</CODE> object. If the interpolation hint is
91 * defined, it will be used. Otherwise, if the rendering quality hint is
92 * defined, the interpolation type is determined from its value. If no
93 * hints are specified (<CODE>hints</CODE> is null),
94 * the interpolation type is {@link #TYPE_NEAREST_NEIGHBOR
95 * TYPE_NEAREST_NEIGHBOR}.
96 *
97 * @param xform The <CODE>AffineTransform</CODE> to use for the
98 * operation.
99 *
100 * @param hints The <CODE>RenderingHints</CODE> object used to specify
101 * the interpolation type for the operation.
102 *
103 * @throws ImagingOpException if the transform is non-invertible.
104 * @see java.awt.RenderingHints#KEY_INTERPOLATION
105 * @see java.awt.RenderingHints#KEY_RENDERING
106 */
107 public AffineTransformOp(AffineTransform xform, RenderingHints hints){
108 validateTransform(xform);
109 this.xform = (AffineTransform) xform.clone();
110 this.hints = hints;
111
112 if (hints != null) {
113 Object value = hints.get(hints.KEY_INTERPOLATION);
114 if (value == null) {
115 value = hints.get(hints.KEY_RENDERING);
116 if (value == hints.VALUE_RENDER_SPEED) {
117 interpolationType = TYPE_NEAREST_NEIGHBOR;
118 }
119 else if (value == hints.VALUE_RENDER_QUALITY) {
120 interpolationType = TYPE_BILINEAR;
121 }
122 }
123 else if (value == hints.VALUE_INTERPOLATION_NEAREST_NEIGHBOR) {
124 interpolationType = TYPE_NEAREST_NEIGHBOR;
125 }
126 else if (value == hints.VALUE_INTERPOLATION_BILINEAR) {
127 interpolationType = TYPE_BILINEAR;
128 }
129 else if (value == hints.VALUE_INTERPOLATION_BICUBIC) {
130 interpolationType = TYPE_BICUBIC;
131 }
132 }
133 else {
134 interpolationType = TYPE_NEAREST_NEIGHBOR;
135 }
136 }
137
138 /**
139 * Constructs an <CODE>AffineTransformOp</CODE> given an affine transform
140 * and the interpolation type.
141 *
142 * @param xform The <CODE>AffineTransform</CODE> to use for the operation.
143 * @param interpolationType One of the integer
144 * interpolation type constants defined by this class:
145 * {@link #TYPE_NEAREST_NEIGHBOR TYPE_NEAREST_NEIGHBOR},
146 * {@link #TYPE_BILINEAR TYPE_BILINEAR},
147 * {@link #TYPE_BICUBIC TYPE_BICUBIC}.
148 * @throws ImagingOpException if the transform is non-invertible.
149 */
150 public AffineTransformOp(AffineTransform xform, int interpolationType) {
151 validateTransform(xform);
152 this.xform = (AffineTransform)xform.clone();
153 switch(interpolationType) {
154 case TYPE_NEAREST_NEIGHBOR:
155 case TYPE_BILINEAR:
156 case TYPE_BICUBIC:
157 break;
158 default:
159 throw new IllegalArgumentException("Unknown interpolation type: "+
160 interpolationType);
161 }
162 this.interpolationType = interpolationType;
163 }
164
165 /**
166 * Returns the interpolation type used by this op.
167 * @return the interpolation type.
168 * @see #TYPE_NEAREST_NEIGHBOR
169 * @see #TYPE_BILINEAR
170 * @see #TYPE_BICUBIC
171 */
172 public final int getInterpolationType() {
173 return interpolationType;
174 }
175
176 /**
177 * Transforms the source <CODE>BufferedImage</CODE> and stores the results
178 * in the destination <CODE>BufferedImage</CODE>.
179 * If the color models for the two images do not match, a color
180 * conversion into the destination color model is performed.
181 * If the destination image is null,
182 * a <CODE>BufferedImage</CODE> is created with the source
183 * <CODE>ColorModel</CODE>.
184 * <p>
185 * The coordinates of the rectangle returned by
186 * <code>getBounds2D(BufferedImage)</code>
187 * are not necessarily the same as the coordinates of the
188 * <code>BufferedImage</code> returned by this method. If the
189 * upper-left corner coordinates of the rectangle are
190 * negative then this part of the rectangle is not drawn. If the
191 * upper-left corner coordinates of the rectangle are positive
192 * then the filtered image is drawn at that position in the
193 * destination <code>BufferedImage</code>.
194 * <p>
195 * An <CODE>IllegalArgumentException</CODE> is thrown if the source is
196 * the same as the destination.
197 *
198 * @param src The <CODE>BufferedImage</CODE> to transform.
199 * @param dst The <CODE>BufferedImage</CODE> in which to store the results
200 * of the transformation.
201 *
202 * @return The filtered <CODE>BufferedImage</CODE>.
203 * @throws IllegalArgumentException if <code>src</code> and
204 * <code>dst</code> are the same
205 * @throws ImagingOpException if the image cannot be transformed
206 * because of a data-processing error that might be
207 * caused by an invalid image format, tile format, or
208 * image-processing operation, or any other unsupported
209 * operation.
210 */
211 public final BufferedImage filter(BufferedImage src, BufferedImage dst) {
212
213 if (src == null) {
214 throw new NullPointerException("src image is null");
215 }
216 if (src == dst) {
217 throw new IllegalArgumentException("src image cannot be the "+
218 "same as the dst image");
219 }
220
221 boolean needToConvert = false;
222 ColorModel srcCM = src.getColorModel();
223 ColorModel dstCM;
224 BufferedImage origDst = dst;
225
226 if (dst == null) {
227 dst = createCompatibleDestImage(src, null);
228 dstCM = srcCM;
229 origDst = dst;
230 }
231 else {
232 dstCM = dst.getColorModel();
233 if (srcCM.getColorSpace().getType() !=
234 dstCM.getColorSpace().getType())
235 {
236 int type = xform.getType();
237 boolean needTrans = ((type&
238 (xform.TYPE_MASK_ROTATION|
239 xform.TYPE_GENERAL_TRANSFORM))
240 != 0);
241 if (! needTrans && type != xform.TYPE_TRANSLATION && type != xform.TYPE_IDENTITY)
242 {
243 double[] mtx = new double[4];
244 xform.getMatrix(mtx);
245 // Check out the matrix. A non-integral scale will force ARGB
246 // since the edge conditions can't be guaranteed.
247 needTrans = (mtx[0] != (int)mtx[0] || mtx[3] != (int)mtx[3]);
248 }
249
250 if (needTrans &&
251 srcCM.getTransparency() == Transparency.OPAQUE)
252 {
253 // Need to convert first
254 ColorConvertOp ccop = new ColorConvertOp(hints);
255 BufferedImage tmpSrc = null;
256 int sw = src.getWidth();
257 int sh = src.getHeight();
258 if (dstCM.getTransparency() == Transparency.OPAQUE) {
259 tmpSrc = new BufferedImage(sw, sh,
260 BufferedImage.TYPE_INT_ARGB);
261 }
262 else {
263 WritableRaster r =
264 dstCM.createCompatibleWritableRaster(sw, sh);
265 tmpSrc = new BufferedImage(dstCM, r,
266 dstCM.isAlphaPremultiplied(),
267 null);
268 }
269 src = ccop.filter(src, tmpSrc);
270 }
271 else {
272 needToConvert = true;
273 dst = createCompatibleDestImage(src, null);
274 }
275 }
276
277 }
278
279 if (interpolationType != TYPE_NEAREST_NEIGHBOR &&
280 dst.getColorModel() instanceof IndexColorModel) {
281 dst = new BufferedImage(dst.getWidth(), dst.getHeight(),
282 BufferedImage.TYPE_INT_ARGB);
283 }
284 if (ImagingLib.filter(this, src, dst) == null) {
285 throw new ImagingOpException ("Unable to transform src image");
286 }
287
288 if (needToConvert) {
289 ColorConvertOp ccop = new ColorConvertOp(hints);
290 ccop.filter(dst, origDst);
291 }
292 else if (origDst != dst) {
293 java.awt.Graphics2D g = origDst.createGraphics();
294 try {
295 g.setComposite(AlphaComposite.Src);
296 g.drawImage(dst, 0, 0, null);
297 } finally {
298 g.dispose();
299 }
300 }
301
302 return origDst;
303 }
304
305 /**
306 * Transforms the source <CODE>Raster</CODE> and stores the results in
307 * the destination <CODE>Raster</CODE>. This operation performs the
308 * transform band by band.
309 * <p>
310 * If the destination <CODE>Raster</CODE> is null, a new
311 * <CODE>Raster</CODE> is created.
312 * An <CODE>IllegalArgumentException</CODE> may be thrown if the source is
313 * the same as the destination or if the number of bands in
314 * the source is not equal to the number of bands in the
315 * destination.
316 * <p>
317 * The coordinates of the rectangle returned by
318 * <code>getBounds2D(Raster)</code>
319 * are not necessarily the same as the coordinates of the
320 * <code>WritableRaster</code> returned by this method. If the
321 * upper-left corner coordinates of rectangle are negative then
322 * this part of the rectangle is not drawn. If the coordinates
323 * of the rectangle are positive then the filtered image is drawn at
324 * that position in the destination <code>Raster</code>.
325 * <p>
326 * @param src The <CODE>Raster</CODE> to transform.
327 * @param dst The <CODE>Raster</CODE> in which to store the results of the
328 * transformation.
329 *
330 * @return The transformed <CODE>Raster</CODE>.
331 *
332 * @throws ImagingOpException if the raster cannot be transformed
333 * because of a data-processing error that might be
334 * caused by an invalid image format, tile format, or
335 * image-processing operation, or any other unsupported
336 * operation.
337 */
338 public final WritableRaster filter(Raster src, WritableRaster dst) {
339 if (src == null) {
340 throw new NullPointerException("src image is null");
341 }
342 if (dst == null) {
343 dst = createCompatibleDestRaster(src);
344 }
345 if (src == dst) {
346 throw new IllegalArgumentException("src image cannot be the "+
347 "same as the dst image");
348 }
349 if (src.getNumBands() != dst.getNumBands()) {
350 throw new IllegalArgumentException("Number of src bands ("+
351 src.getNumBands()+
352 ") does not match number of "+
353 " dst bands ("+
354 dst.getNumBands()+")");
355 }
356
357 if (ImagingLib.filter(this, src, dst) == null) {
358 throw new ImagingOpException ("Unable to transform src image");
359 }
360 return dst;
361 }
362
363 /**
364 * Returns the bounding box of the transformed destination. The
365 * rectangle returned is the actual bounding box of the
366 * transformed points. The coordinates of the upper-left corner
367 * of the returned rectangle might not be (0, 0).
368 *
369 * @param src The <CODE>BufferedImage</CODE> to be transformed.
370 *
371 * @return The <CODE>Rectangle2D</CODE> representing the destination's
372 * bounding box.
373 */
374 public final Rectangle2D getBounds2D (BufferedImage src) {
375 return getBounds2D(src.getRaster());
376 }
377
378 /**
379 * Returns the bounding box of the transformed destination. The
380 * rectangle returned will be the actual bounding box of the
381 * transformed points. The coordinates of the upper-left corner
382 * of the returned rectangle might not be (0, 0).
383 *
384 * @param src The <CODE>Raster</CODE> to be transformed.
385 *
386 * @return The <CODE>Rectangle2D</CODE> representing the destination's
387 * bounding box.
388 */
389 public final Rectangle2D getBounds2D (Raster src) {
390 int w = src.getWidth();
391 int h = src.getHeight();
392
393 // Get the bounding box of the src and transform the corners
394 float[] pts = {0, 0, w, 0, w, h, 0, h};
395 xform.transform(pts, 0, pts, 0, 4);
396
397 // Get the min, max of the dst
398 float fmaxX = pts[0];
399 float fmaxY = pts[1];
400 float fminX = pts[0];
401 float fminY = pts[1];
402 for (int i=2; i < 8; i+=2) {
403 if (pts[i] > fmaxX) {
404 fmaxX = pts[i];
405 }
406 else if (pts[i] < fminX) {
407 fminX = pts[i];
408 }
409 if (pts[i+1] > fmaxY) {
410 fmaxY = pts[i+1];
411 }
412 else if (pts[i+1] < fminY) {
413 fminY = pts[i+1];
414 }
415 }
416
417 return new Rectangle2D.Float(fminX, fminY, fmaxX-fminX, fmaxY-fminY);
418 }
419
420 /**
421 * Creates a zeroed destination image with the correct size and number of
422 * bands. A <CODE>RasterFormatException</CODE> may be thrown if the
423 * transformed width or height is equal to 0.
424 * <p>
425 * If <CODE>destCM</CODE> is null,
426 * an appropriate <CODE>ColorModel</CODE> is used; this
427 * <CODE>ColorModel</CODE> may have
428 * an alpha channel even if the source <CODE>ColorModel</CODE> is opaque.
429 *
430 * @param src The <CODE>BufferedImage</CODE> to be transformed.
431 * @param destCM <CODE>ColorModel</CODE> of the destination. If null,
432 * an appropriate <CODE>ColorModel</CODE> is used.
433 *
434 * @return The zeroed destination image.
435 */
436 public BufferedImage createCompatibleDestImage (BufferedImage src,
437 ColorModel destCM) {
438 BufferedImage image;
439 Rectangle r = getBounds2D(src).getBounds();
440
441 // If r.x (or r.y) is < 0, then we want to only create an image
442 // that is in the positive range.
443 // If r.x (or r.y) is > 0, then we need to create an image that
444 // includes the translation.
445 int w = r.x + r.width;
446 int h = r.y + r.height;
447 if (w <= 0) {
448 throw new RasterFormatException("Transformed width ("+w+
449 ") is less than or equal to 0.");
450 }
451 if (h <= 0) {
452 throw new RasterFormatException("Transformed height ("+h+
453 ") is less than or equal to 0.");
454 }
455
456 if (destCM == null) {
457 ColorModel cm = src.getColorModel();
458 if (interpolationType != TYPE_NEAREST_NEIGHBOR &&
459 (cm instanceof IndexColorModel ||
460 cm.getTransparency() == Transparency.OPAQUE))
461 {
462 image = new BufferedImage(w, h,
463 BufferedImage.TYPE_INT_ARGB);
464 }
465 else {
466 image = new BufferedImage(cm,
467 src.getRaster().createCompatibleWritableRaster(w,h),
468 cm.isAlphaPremultiplied(), null);
469 }
470 }
471 else {
472 image = new BufferedImage(destCM,
473 destCM.createCompatibleWritableRaster(w,h),
474 destCM.isAlphaPremultiplied(), null);
475 }
476
477 return image;
478 }
479
480 /**
481 * Creates a zeroed destination <CODE>Raster</CODE> with the correct size
482 * and number of bands. A <CODE>RasterFormatException</CODE> may be thrown
483 * if the transformed width or height is equal to 0.
484 *
485 * @param src The <CODE>Raster</CODE> to be transformed.
486 *
487 * @return The zeroed destination <CODE>Raster</CODE>.
488 */
489 public WritableRaster createCompatibleDestRaster (Raster src) {
490 Rectangle2D r = getBounds2D(src);
491
492 return src.createCompatibleWritableRaster((int)r.getX(),
493 (int)r.getY(),
494 (int)r.getWidth(),
495 (int)r.getHeight());
496 }
497
498 /**
499 * Returns the location of the corresponding destination point given a
500 * point in the source. If <CODE>dstPt</CODE> is specified, it
501 * is used to hold the return value.
502 *
503 * @param srcPt The <code>Point2D</code> that represents the source
504 * point.
505 * @param dstPt The <CODE>Point2D</CODE> in which to store the result.
506 *
507 * @return The <CODE>Point2D</CODE> in the destination that corresponds to
508 * the specified point in the source.
509 */
510 public final Point2D getPoint2D (Point2D srcPt, Point2D dstPt) {
511 return xform.transform (srcPt, dstPt);
512 }
513
514 /**
515 * Returns the affine transform used by this transform operation.
516 *
517 * @return The <CODE>AffineTransform</CODE> associated with this op.
518 */
519 public final AffineTransform getTransform() {
520 return (AffineTransform) xform.clone();
521 }
522
523 /**
524 * Returns the rendering hints used by this transform operation.
525 *
526 * @return The <CODE>RenderingHints</CODE> object associated with this op.
527 */
528 public final RenderingHints getRenderingHints() {
529 if (hints == null) {
530 Object val;
531 switch(interpolationType) {
532 case TYPE_NEAREST_NEIGHBOR:
533 val = RenderingHints.VALUE_INTERPOLATION_NEAREST_NEIGHBOR;
534 break;
535 case TYPE_BILINEAR:
536 val = RenderingHints.VALUE_INTERPOLATION_BILINEAR;
537 break;
538 case TYPE_BICUBIC:
539 val = RenderingHints.VALUE_INTERPOLATION_BICUBIC;
540 break;
541 default:
542 // Should never get here
543 throw new InternalError("Unknown interpolation type "+
544 interpolationType);
545
546 }
547 hints = new RenderingHints(RenderingHints.KEY_INTERPOLATION, val);
548 }
549
550 return hints;
551 }
552
553 // We need to be able to invert the transform if we want to
554 // transform the image. If the determinant of the matrix is 0,
555 // then we can't invert the transform.
556 void validateTransform(AffineTransform xform) {
557 if (Math.abs(xform.getDeterminant()) <= Double.MIN_VALUE) {
558 throw new ImagingOpException("Unable to invert transform "+xform);
559 }
560 }
561 }