1 /*
2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 % %
4 % %
5 % %
6 % SSSSS H H EEEEE AAA RRRR %
7 % SS H H E A A R R %
8 % SSS HHHHH EEE AAAAA RRRR %
9 % SS H H E A A R R %
10 % SSSSS H H EEEEE A A R R %
11 % %
12 % %
13 % MagickCore Methods to Shear or Rotate an Image by an Arbitrary Angle %
14 % %
15 % Software Design %
16 % Cristy %
17 % July 1992 %
18 % %
19 % %
20 % Copyright 1999-2019 ImageMagick Studio LLC, a non-profit organization %
21 % dedicated to making software imaging solutions freely available. %
22 % %
23 % You may not use this file except in compliance with the License. You may %
24 % obtain a copy of the License at %
25 % %
26 % https://imagemagick.org/script/license.php %
27 % %
28 % Unless required by applicable law or agreed to in writing, software %
29 % distributed under the License is distributed on an "AS IS" BASIS, %
30 % WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
31 % See the License for the specific language governing permissions and %
32 % limitations under the License. %
33 % %
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
35 %
36 % The XShearImage() and YShearImage() methods are based on the paper "A Fast
37 % Algorithm for General Raster Rotation" by Alan W. Paeth, Graphics
38 % Interface '86 (Vancouver). ShearRotateImage() is adapted from a similar
39 % method based on the Paeth paper written by Michael Halle of the Spatial
40 % Imaging Group, MIT Media Lab.
41 %
42 */
43
44 /*
45 Include declarations.
46 */
47 #include "MagickCore/studio.h"
48 #include "MagickCore/artifact.h"
49 #include "MagickCore/attribute.h"
50 #include "MagickCore/blob-private.h"
51 #include "MagickCore/cache-private.h"
52 #include "MagickCore/channel.h"
53 #include "MagickCore/color-private.h"
54 #include "MagickCore/colorspace-private.h"
55 #include "MagickCore/composite.h"
56 #include "MagickCore/composite-private.h"
57 #include "MagickCore/decorate.h"
58 #include "MagickCore/distort.h"
59 #include "MagickCore/draw.h"
60 #include "MagickCore/exception.h"
61 #include "MagickCore/exception-private.h"
62 #include "MagickCore/gem.h"
63 #include "MagickCore/geometry.h"
64 #include "MagickCore/image.h"
65 #include "MagickCore/image-private.h"
66 #include "MagickCore/matrix.h"
67 #include "MagickCore/memory_.h"
68 #include "MagickCore/list.h"
69 #include "MagickCore/monitor.h"
70 #include "MagickCore/monitor-private.h"
71 #include "MagickCore/nt-base-private.h"
72 #include "MagickCore/pixel-accessor.h"
73 #include "MagickCore/quantum.h"
74 #include "MagickCore/resource_.h"
75 #include "MagickCore/shear.h"
76 #include "MagickCore/statistic.h"
77 #include "MagickCore/string_.h"
78 #include "MagickCore/string-private.h"
79 #include "MagickCore/thread-private.h"
80 #include "MagickCore/threshold.h"
81 #include "MagickCore/transform.h"
82
83 /*
84 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
85 % %
86 % %
87 % %
88 + C r o p T o F i t I m a g e %
89 % %
90 % %
91 % %
92 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
93 %
94 % CropToFitImage() crops the sheared image as determined by the bounding box
95 % as defined by width and height and shearing angles.
96 %
97 % The format of the CropToFitImage method is:
98 %
99 % MagickBooleanType CropToFitImage(Image **image,
100 % const double x_shear,const double x_shear,
101 % const double width,const double height,
102 % const MagickBooleanType rotate,ExceptionInfo *exception)
103 %
104 % A description of each parameter follows.
105 %
106 % o image: the image.
107 %
108 % o x_shear, y_shear, width, height: Defines a region of the image to crop.
109 %
110 % o exception: return any errors or warnings in this structure.
111 %
112 */
CropToFitImage(Image ** image,const double x_shear,const double y_shear,const double width,const double height,const MagickBooleanType rotate,ExceptionInfo * exception)113 static MagickBooleanType CropToFitImage(Image **image,
114 const double x_shear,const double y_shear,
115 const double width,const double height,
116 const MagickBooleanType rotate,ExceptionInfo *exception)
117 {
118 Image
119 *crop_image;
120
121 PointInfo
122 extent[4],
123 min,
124 max;
125
126 RectangleInfo
127 geometry,
128 page;
129
130 register ssize_t
131 i;
132
133 /*
134 Calculate the rotated image size.
135 */
136 extent[0].x=(double) (-width/2.0);
137 extent[0].y=(double) (-height/2.0);
138 extent[1].x=(double) width/2.0;
139 extent[1].y=(double) (-height/2.0);
140 extent[2].x=(double) (-width/2.0);
141 extent[2].y=(double) height/2.0;
142 extent[3].x=(double) width/2.0;
143 extent[3].y=(double) height/2.0;
144 for (i=0; i < 4; i++)
145 {
146 extent[i].x+=x_shear*extent[i].y;
147 extent[i].y+=y_shear*extent[i].x;
148 if (rotate != MagickFalse)
149 extent[i].x+=x_shear*extent[i].y;
150 extent[i].x+=(double) (*image)->columns/2.0;
151 extent[i].y+=(double) (*image)->rows/2.0;
152 }
153 min=extent[0];
154 max=extent[0];
155 for (i=1; i < 4; i++)
156 {
157 if (min.x > extent[i].x)
158 min.x=extent[i].x;
159 if (min.y > extent[i].y)
160 min.y=extent[i].y;
161 if (max.x < extent[i].x)
162 max.x=extent[i].x;
163 if (max.y < extent[i].y)
164 max.y=extent[i].y;
165 }
166 geometry.x=(ssize_t) ceil(min.x-0.5);
167 geometry.y=(ssize_t) ceil(min.y-0.5);
168 geometry.width=(size_t) floor(max.x-min.x+0.5);
169 geometry.height=(size_t) floor(max.y-min.y+0.5);
170 page=(*image)->page;
171 (void) ParseAbsoluteGeometry("0x0+0+0",&(*image)->page);
172 crop_image=CropImage(*image,&geometry,exception);
173 if (crop_image == (Image *) NULL)
174 return(MagickFalse);
175 crop_image->page=page;
176 *image=DestroyImage(*image);
177 *image=crop_image;
178 return(MagickTrue);
179 }
180
181 /*
182 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
183 % %
184 % %
185 % %
186 % D e s k e w I m a g e %
187 % %
188 % %
189 % %
190 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
191 %
192 % DeskewImage() removes skew from the image. Skew is an artifact that
193 % occurs in scanned images because of the camera being misaligned,
194 % imperfections in the scanning or surface, or simply because the paper was
195 % not placed completely flat when scanned.
196 %
197 % The result will be auto-croped if the artifact "deskew:auto-crop" is
198 % defined, while the amount the image is to be deskewed, in degrees is also
199 % saved as the artifact "deskew:angle".
200 %
201 % The format of the DeskewImage method is:
202 %
203 % Image *DeskewImage(const Image *image,const double threshold,
204 % ExceptionInfo *exception)
205 %
206 % A description of each parameter follows:
207 %
208 % o image: the image.
209 %
210 % o threshold: separate background from foreground.
211 %
212 % o exception: return any errors or warnings in this structure.
213 %
214 */
215
RadonProjection(const Image * image,MatrixInfo * source_matrixs,MatrixInfo * destination_matrixs,const ssize_t sign,size_t * projection)216 static void RadonProjection(const Image *image,MatrixInfo *source_matrixs,
217 MatrixInfo *destination_matrixs,const ssize_t sign,size_t *projection)
218 {
219 MatrixInfo
220 *swap;
221
222 register MatrixInfo
223 *p,
224 *q;
225
226 register ssize_t
227 x;
228
229 size_t
230 step;
231
232 p=source_matrixs;
233 q=destination_matrixs;
234 for (step=1; step < GetMatrixColumns(p); step*=2)
235 {
236 for (x=0; x < (ssize_t) GetMatrixColumns(p); x+=2*(ssize_t) step)
237 {
238 register ssize_t
239 i;
240
241 ssize_t
242 y;
243
244 unsigned short
245 element,
246 neighbor;
247
248 for (i=0; i < (ssize_t) step; i++)
249 {
250 for (y=0; y < (ssize_t) (GetMatrixRows(p)-i-1); y++)
251 {
252 if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
253 continue;
254 if (GetMatrixElement(p,x+i+step,y+i,&neighbor) == MagickFalse)
255 continue;
256 neighbor+=element;
257 if (SetMatrixElement(q,x+2*i,y,&neighbor) == MagickFalse)
258 continue;
259 if (GetMatrixElement(p,x+i+step,y+i+1,&neighbor) == MagickFalse)
260 continue;
261 neighbor+=element;
262 if (SetMatrixElement(q,x+2*i+1,y,&neighbor) == MagickFalse)
263 continue;
264 }
265 for ( ; y < (ssize_t) (GetMatrixRows(p)-i); y++)
266 {
267 if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
268 continue;
269 if (GetMatrixElement(p,x+i+step,y+i,&neighbor) == MagickFalse)
270 continue;
271 neighbor+=element;
272 if (SetMatrixElement(q,x+2*i,y,&neighbor) == MagickFalse)
273 continue;
274 if (SetMatrixElement(q,x+2*i+1,y,&element) == MagickFalse)
275 continue;
276 }
277 for ( ; y < (ssize_t) GetMatrixRows(p); y++)
278 {
279 if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
280 continue;
281 if (SetMatrixElement(q,x+2*i,y,&element) == MagickFalse)
282 continue;
283 if (SetMatrixElement(q,x+2*i+1,y,&element) == MagickFalse)
284 continue;
285 }
286 }
287 }
288 swap=p;
289 p=q;
290 q=swap;
291 }
292 #if defined(MAGICKCORE_OPENMP_SUPPORT)
293 #pragma omp parallel for schedule(static) \
294 magick_number_threads(image,image,GetMatrixColumns(p),1)
295 #endif
296 for (x=0; x < (ssize_t) GetMatrixColumns(p); x++)
297 {
298 register ssize_t
299 y;
300
301 size_t
302 sum;
303
304 sum=0;
305 for (y=0; y < (ssize_t) (GetMatrixRows(p)-1); y++)
306 {
307 ssize_t
308 delta;
309
310 unsigned short
311 element,
312 neighbor;
313
314 if (GetMatrixElement(p,x,y,&element) == MagickFalse)
315 continue;
316 if (GetMatrixElement(p,x,y+1,&neighbor) == MagickFalse)
317 continue;
318 delta=(ssize_t) element-(ssize_t) neighbor;
319 sum+=delta*delta;
320 }
321 projection[GetMatrixColumns(p)+sign*x-1]=sum;
322 }
323 }
324
RadonTransform(const Image * image,const double threshold,size_t * projection,ExceptionInfo * exception)325 static MagickBooleanType RadonTransform(const Image *image,
326 const double threshold,size_t *projection,ExceptionInfo *exception)
327 {
328 CacheView
329 *image_view;
330
331 MatrixInfo
332 *destination_matrixs,
333 *source_matrixs;
334
335 MagickBooleanType
336 status;
337
338 size_t
339 count,
340 width;
341
342 ssize_t
343 j,
344 y;
345
346 unsigned char
347 c;
348
349 unsigned short
350 bits[256];
351
352 for (width=1; width < ((image->columns+7)/8); width<<=1) ;
353 source_matrixs=AcquireMatrixInfo(width,image->rows,sizeof(unsigned short),
354 exception);
355 destination_matrixs=AcquireMatrixInfo(width,image->rows,
356 sizeof(unsigned short),exception);
357 if ((source_matrixs == (MatrixInfo *) NULL) ||
358 (destination_matrixs == (MatrixInfo *) NULL))
359 {
360 if (destination_matrixs != (MatrixInfo *) NULL)
361 destination_matrixs=DestroyMatrixInfo(destination_matrixs);
362 if (source_matrixs != (MatrixInfo *) NULL)
363 source_matrixs=DestroyMatrixInfo(source_matrixs);
364 return(MagickFalse);
365 }
366 if (NullMatrix(source_matrixs) == MagickFalse)
367 {
368 destination_matrixs=DestroyMatrixInfo(destination_matrixs);
369 source_matrixs=DestroyMatrixInfo(source_matrixs);
370 return(MagickFalse);
371 }
372 for (j=0; j < 256; j++)
373 {
374 c=(unsigned char) j;
375 for (count=0; c != 0; c>>=1)
376 count+=c & 0x01;
377 bits[j]=(unsigned short) count;
378 }
379 status=MagickTrue;
380 image_view=AcquireVirtualCacheView(image,exception);
381 #if defined(MAGICKCORE_OPENMP_SUPPORT)
382 #pragma omp parallel for schedule(static) shared(status) \
383 magick_number_threads(image,image,image->rows,1)
384 #endif
385 for (y=0; y < (ssize_t) image->rows; y++)
386 {
387 register const Quantum
388 *magick_restrict p;
389
390 register ssize_t
391 i,
392 x;
393
394 size_t
395 bit,
396 byte;
397
398 unsigned short
399 value;
400
401 if (status == MagickFalse)
402 continue;
403 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
404 if (p == (const Quantum *) NULL)
405 {
406 status=MagickFalse;
407 continue;
408 }
409 bit=0;
410 byte=0;
411 i=(ssize_t) (image->columns+7)/8;
412 for (x=0; x < (ssize_t) image->columns; x++)
413 {
414 byte<<=1;
415 if (((MagickRealType) GetPixelRed(image,p) < threshold) ||
416 ((MagickRealType) GetPixelGreen(image,p) < threshold) ||
417 ((MagickRealType) GetPixelBlue(image,p) < threshold))
418 byte|=0x01;
419 bit++;
420 if (bit == 8)
421 {
422 value=bits[byte];
423 (void) SetMatrixElement(source_matrixs,--i,y,&value);
424 bit=0;
425 byte=0;
426 }
427 p+=GetPixelChannels(image);
428 }
429 if (bit != 0)
430 {
431 byte<<=(8-bit);
432 value=bits[byte];
433 (void) SetMatrixElement(source_matrixs,--i,y,&value);
434 }
435 }
436 RadonProjection(image,source_matrixs,destination_matrixs,-1,projection);
437 (void) NullMatrix(source_matrixs);
438 #if defined(MAGICKCORE_OPENMP_SUPPORT)
439 #pragma omp parallel for schedule(static) shared(status) \
440 magick_number_threads(image,image,image->rows,1)
441 #endif
442 for (y=0; y < (ssize_t) image->rows; y++)
443 {
444 register const Quantum
445 *magick_restrict p;
446
447 register ssize_t
448 i,
449 x;
450
451 size_t
452 bit,
453 byte;
454
455 unsigned short
456 value;
457
458 if (status == MagickFalse)
459 continue;
460 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
461 if (p == (const Quantum *) NULL)
462 {
463 status=MagickFalse;
464 continue;
465 }
466 bit=0;
467 byte=0;
468 i=0;
469 for (x=0; x < (ssize_t) image->columns; x++)
470 {
471 byte<<=1;
472 if (((MagickRealType) GetPixelRed(image,p) < threshold) ||
473 ((MagickRealType) GetPixelGreen(image,p) < threshold) ||
474 ((MagickRealType) GetPixelBlue(image,p) < threshold))
475 byte|=0x01;
476 bit++;
477 if (bit == 8)
478 {
479 value=bits[byte];
480 (void) SetMatrixElement(source_matrixs,i++,y,&value);
481 bit=0;
482 byte=0;
483 }
484 p+=GetPixelChannels(image);
485 }
486 if (bit != 0)
487 {
488 byte<<=(8-bit);
489 value=bits[byte];
490 (void) SetMatrixElement(source_matrixs,i++,y,&value);
491 }
492 }
493 RadonProjection(image,source_matrixs,destination_matrixs,1,projection);
494 image_view=DestroyCacheView(image_view);
495 destination_matrixs=DestroyMatrixInfo(destination_matrixs);
496 source_matrixs=DestroyMatrixInfo(source_matrixs);
497 return(MagickTrue);
498 }
499
GetImageBackgroundColor(Image * image,const ssize_t offset,ExceptionInfo * exception)500 static void GetImageBackgroundColor(Image *image,const ssize_t offset,
501 ExceptionInfo *exception)
502 {
503 CacheView
504 *image_view;
505
506 PixelInfo
507 background;
508
509 double
510 count;
511
512 ssize_t
513 y;
514
515 /*
516 Compute average background color.
517 */
518 if (offset <= 0)
519 return;
520 GetPixelInfo(image,&background);
521 count=0.0;
522 image_view=AcquireVirtualCacheView(image,exception);
523 for (y=0; y < (ssize_t) image->rows; y++)
524 {
525 register const Quantum
526 *magick_restrict p;
527
528 register ssize_t
529 x;
530
531 if ((y >= offset) && (y < ((ssize_t) image->rows-offset)))
532 continue;
533 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
534 if (p == (const Quantum *) NULL)
535 continue;
536 for (x=0; x < (ssize_t) image->columns; x++)
537 {
538 if ((x >= offset) && (x < ((ssize_t) image->columns-offset)))
539 continue;
540 background.red+=QuantumScale*GetPixelRed(image,p);
541 background.green+=QuantumScale*GetPixelGreen(image,p);
542 background.blue+=QuantumScale*GetPixelBlue(image,p);
543 if ((GetPixelAlphaTraits(image) & UpdatePixelTrait) != 0)
544 background.alpha+=QuantumScale*GetPixelAlpha(image,p);
545 count++;
546 p+=GetPixelChannels(image);
547 }
548 }
549 image_view=DestroyCacheView(image_view);
550 image->background_color.red=(double) ClampToQuantum(QuantumRange*
551 background.red/count);
552 image->background_color.green=(double) ClampToQuantum(QuantumRange*
553 background.green/count);
554 image->background_color.blue=(double) ClampToQuantum(QuantumRange*
555 background.blue/count);
556 if ((GetPixelAlphaTraits(image) & UpdatePixelTrait) != 0)
557 image->background_color.alpha=(double) ClampToQuantum(QuantumRange*
558 background.alpha/count);
559 }
560
DeskewImage(const Image * image,const double threshold,ExceptionInfo * exception)561 MagickExport Image *DeskewImage(const Image *image,const double threshold,
562 ExceptionInfo *exception)
563 {
564 AffineMatrix
565 affine_matrix;
566
567 const char
568 *artifact;
569
570 double
571 degrees;
572
573 Image
574 *clone_image,
575 *crop_image,
576 *deskew_image,
577 *median_image;
578
579 MagickBooleanType
580 status;
581
582 RectangleInfo
583 geometry;
584
585 register ssize_t
586 i;
587
588 size_t
589 max_projection,
590 *projection,
591 width;
592
593 ssize_t
594 skew;
595
596 /*
597 Compute deskew angle.
598 */
599 for (width=1; width < ((image->columns+7)/8); width<<=1) ;
600 projection=(size_t *) AcquireQuantumMemory((size_t) (2*width-1),
601 sizeof(*projection));
602 if (projection == (size_t *) NULL)
603 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
604 status=RadonTransform(image,threshold,projection,exception);
605 if (status == MagickFalse)
606 {
607 projection=(size_t *) RelinquishMagickMemory(projection);
608 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
609 }
610 max_projection=0;
611 skew=0;
612 for (i=0; i < (ssize_t) (2*width-1); i++)
613 {
614 if (projection[i] > max_projection)
615 {
616 skew=i-(ssize_t) width+1;
617 max_projection=projection[i];
618 }
619 }
620 projection=(size_t *) RelinquishMagickMemory(projection);
621 degrees=RadiansToDegrees(-atan((double) skew/width/8));
622 if (image->debug != MagickFalse)
623 (void) LogMagickEvent(TransformEvent,GetMagickModule(),
624 " Deskew angle: %g",degrees);
625 /*
626 Deskew image.
627 */
628 clone_image=CloneImage(image,0,0,MagickTrue,exception);
629 if (clone_image == (Image *) NULL)
630 return((Image *) NULL);
631 {
632 char
633 angle[MagickPathExtent];
634
635 (void) FormatLocaleString(angle,MagickPathExtent,"%.20g",degrees);
636 (void) SetImageArtifact(clone_image,"deskew:angle",angle);
637 }
638 (void) SetImageVirtualPixelMethod(clone_image,BackgroundVirtualPixelMethod,
639 exception);
640 affine_matrix.sx=cos(DegreesToRadians(fmod((double) degrees,360.0)));
641 affine_matrix.rx=sin(DegreesToRadians(fmod((double) degrees,360.0)));
642 affine_matrix.ry=(-sin(DegreesToRadians(fmod((double) degrees,360.0))));
643 affine_matrix.sy=cos(DegreesToRadians(fmod((double) degrees,360.0)));
644 affine_matrix.tx=0.0;
645 affine_matrix.ty=0.0;
646 artifact=GetImageArtifact(image,"deskew:auto-crop");
647 if (IsStringTrue(artifact) == MagickFalse)
648 {
649 deskew_image=AffineTransformImage(clone_image,&affine_matrix,exception);
650 clone_image=DestroyImage(clone_image);
651 return(deskew_image);
652 }
653 /*
654 Auto-crop image.
655 */
656 GetImageBackgroundColor(clone_image,(ssize_t) StringToLong(artifact),
657 exception);
658 deskew_image=AffineTransformImage(clone_image,&affine_matrix,exception);
659 clone_image=DestroyImage(clone_image);
660 if (deskew_image == (Image *) NULL)
661 return((Image *) NULL);
662 median_image=StatisticImage(deskew_image,MedianStatistic,3,3,exception);
663 if (median_image == (Image *) NULL)
664 {
665 deskew_image=DestroyImage(deskew_image);
666 return((Image *) NULL);
667 }
668 geometry=GetImageBoundingBox(median_image,exception);
669 median_image=DestroyImage(median_image);
670 if (image->debug != MagickFalse)
671 (void) LogMagickEvent(TransformEvent,GetMagickModule()," Deskew geometry: "
672 "%.20gx%.20g%+.20g%+.20g",(double) geometry.width,(double)
673 geometry.height,(double) geometry.x,(double) geometry.y);
674 crop_image=CropImage(deskew_image,&geometry,exception);
675 deskew_image=DestroyImage(deskew_image);
676 return(crop_image);
677 }
678
679 /*
680 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
681 % %
682 % %
683 % %
684 % I n t e g r a l R o t a t e I m a g e %
685 % %
686 % %
687 % %
688 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
689 %
690 % IntegralRotateImage() rotates the image an integral of 90 degrees. It
691 % allocates the memory necessary for the new Image structure and returns a
692 % pointer to the rotated image.
693 %
694 % The format of the IntegralRotateImage method is:
695 %
696 % Image *IntegralRotateImage(const Image *image,size_t rotations,
697 % ExceptionInfo *exception)
698 %
699 % A description of each parameter follows.
700 %
701 % o image: the image.
702 %
703 % o rotations: Specifies the number of 90 degree rotations.
704 %
705 */
IntegralRotateImage(const Image * image,size_t rotations,ExceptionInfo * exception)706 MagickExport Image *IntegralRotateImage(const Image *image,size_t rotations,
707 ExceptionInfo *exception)
708 {
709 #define RotateImageTag "Rotate/Image"
710
711 CacheView
712 *image_view,
713 *rotate_view;
714
715 Image
716 *rotate_image;
717
718 MagickBooleanType
719 status;
720
721 MagickOffsetType
722 progress;
723
724 RectangleInfo
725 page;
726
727 /*
728 Initialize rotated image attributes.
729 */
730 assert(image != (Image *) NULL);
731 page=image->page;
732 rotations%=4;
733 if (rotations == 0)
734 return(CloneImage(image,0,0,MagickTrue,exception));
735 if ((rotations == 1) || (rotations == 3))
736 rotate_image=CloneImage(image,image->rows,image->columns,MagickTrue,
737 exception);
738 else
739 rotate_image=CloneImage(image,0,0,MagickTrue,
740 exception);
741 if (rotate_image == (Image *) NULL)
742 return((Image *) NULL);
743 /*
744 Integral rotate the image.
745 */
746 status=MagickTrue;
747 progress=0;
748 image_view=AcquireVirtualCacheView(image,exception);
749 rotate_view=AcquireAuthenticCacheView(rotate_image,exception);
750 switch (rotations)
751 {
752 case 1:
753 {
754 size_t
755 tile_height,
756 tile_width;
757
758 ssize_t
759 tile_y;
760
761 /*
762 Rotate 90 degrees.
763 */
764 GetPixelCacheTileSize(image,&tile_width,&tile_height);
765 tile_width=image->columns;
766 #if defined(MAGICKCORE_OPENMP_SUPPORT)
767 #pragma omp parallel for schedule(static) shared(status) \
768 magick_number_threads(image,image,image->rows/tile_height,1)
769 #endif
770 for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
771 {
772 register ssize_t
773 tile_x;
774
775 if (status == MagickFalse)
776 continue;
777 tile_x=0;
778 for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
779 {
780 MagickBooleanType
781 sync;
782
783 register const Quantum
784 *magick_restrict p;
785
786 register Quantum
787 *magick_restrict q;
788
789 register ssize_t
790 y;
791
792 size_t
793 height,
794 width;
795
796 width=tile_width;
797 if ((tile_x+(ssize_t) tile_width) > (ssize_t) image->columns)
798 width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
799 height=tile_height;
800 if ((tile_y+(ssize_t) tile_height) > (ssize_t) image->rows)
801 height=(size_t) (tile_height-(tile_y+tile_height-image->rows));
802 p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
803 exception);
804 if (p == (const Quantum *) NULL)
805 {
806 status=MagickFalse;
807 break;
808 }
809 for (y=0; y < (ssize_t) width; y++)
810 {
811 register const Quantum
812 *magick_restrict tile_pixels;
813
814 register ssize_t
815 x;
816
817 if (status == MagickFalse)
818 continue;
819 q=QueueCacheViewAuthenticPixels(rotate_view,(ssize_t)
820 (rotate_image->columns-(tile_y+height)),y+tile_x,height,1,
821 exception);
822 if (q == (Quantum *) NULL)
823 {
824 status=MagickFalse;
825 continue;
826 }
827 tile_pixels=p+((height-1)*width+y)*GetPixelChannels(image);
828 for (x=0; x < (ssize_t) height; x++)
829 {
830 register ssize_t
831 i;
832
833 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
834 {
835 PixelChannel channel = GetPixelChannelChannel(image,i);
836 PixelTrait traits = GetPixelChannelTraits(image,channel);
837 PixelTrait rotate_traits=GetPixelChannelTraits(rotate_image,
838 channel);
839 if ((traits == UndefinedPixelTrait) ||
840 (rotate_traits == UndefinedPixelTrait))
841 continue;
842 SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
843 }
844 tile_pixels-=width*GetPixelChannels(image);
845 q+=GetPixelChannels(rotate_image);
846 }
847 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
848 if (sync == MagickFalse)
849 status=MagickFalse;
850 }
851 }
852 if (image->progress_monitor != (MagickProgressMonitor) NULL)
853 {
854 MagickBooleanType
855 proceed;
856
857 proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
858 image->rows);
859 if (proceed == MagickFalse)
860 status=MagickFalse;
861 }
862 }
863 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
864 image->rows-1,image->rows);
865 Swap(page.width,page.height);
866 Swap(page.x,page.y);
867 if (page.width != 0)
868 page.x=(ssize_t) (page.width-rotate_image->columns-page.x);
869 break;
870 }
871 case 2:
872 {
873 register ssize_t
874 y;
875
876 /*
877 Rotate 180 degrees.
878 */
879 #if defined(MAGICKCORE_OPENMP_SUPPORT)
880 #pragma omp parallel for schedule(static) shared(status) \
881 magick_number_threads(image,image,image->rows,1)
882 #endif
883 for (y=0; y < (ssize_t) image->rows; y++)
884 {
885 MagickBooleanType
886 sync;
887
888 register const Quantum
889 *magick_restrict p;
890
891 register Quantum
892 *magick_restrict q;
893
894 register ssize_t
895 x;
896
897 if (status == MagickFalse)
898 continue;
899 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
900 q=QueueCacheViewAuthenticPixels(rotate_view,0,(ssize_t) (image->rows-y-
901 1),image->columns,1,exception);
902 if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
903 {
904 status=MagickFalse;
905 continue;
906 }
907 q+=GetPixelChannels(rotate_image)*image->columns;
908 for (x=0; x < (ssize_t) image->columns; x++)
909 {
910 register ssize_t
911 i;
912
913 q-=GetPixelChannels(rotate_image);
914 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
915 {
916 PixelChannel channel = GetPixelChannelChannel(image,i);
917 PixelTrait traits = GetPixelChannelTraits(image,channel);
918 PixelTrait rotate_traits=GetPixelChannelTraits(rotate_image,
919 channel);
920 if ((traits == UndefinedPixelTrait) ||
921 (rotate_traits == UndefinedPixelTrait))
922 continue;
923 SetPixelChannel(rotate_image,channel,p[i],q);
924 }
925 p+=GetPixelChannels(image);
926 }
927 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
928 if (sync == MagickFalse)
929 status=MagickFalse;
930 if (image->progress_monitor != (MagickProgressMonitor) NULL)
931 {
932 MagickBooleanType
933 proceed;
934
935 proceed=SetImageProgress(image,RotateImageTag,progress++,
936 image->rows);
937 if (proceed == MagickFalse)
938 status=MagickFalse;
939 }
940 }
941 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
942 image->rows-1,image->rows);
943 if (page.width != 0)
944 page.x=(ssize_t) (page.width-rotate_image->columns-page.x);
945 if (page.height != 0)
946 page.y=(ssize_t) (page.height-rotate_image->rows-page.y);
947 break;
948 }
949 case 3:
950 {
951 size_t
952 tile_height,
953 tile_width;
954
955 ssize_t
956 tile_y;
957
958 /*
959 Rotate 270 degrees.
960 */
961 GetPixelCacheTileSize(image,&tile_width,&tile_height);
962 tile_width=image->columns;
963 #if defined(MAGICKCORE_OPENMP_SUPPORT)
964 #pragma omp parallel for schedule(static) shared(status) \
965 magick_number_threads(image,image,image->rows/tile_height,1)
966 #endif
967 for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
968 {
969 register ssize_t
970 tile_x;
971
972 if (status == MagickFalse)
973 continue;
974 tile_x=0;
975 for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
976 {
977 MagickBooleanType
978 sync;
979
980 register const Quantum
981 *magick_restrict p;
982
983 register Quantum
984 *magick_restrict q;
985
986 register ssize_t
987 y;
988
989 size_t
990 height,
991 width;
992
993 width=tile_width;
994 if ((tile_x+(ssize_t) tile_width) > (ssize_t) image->columns)
995 width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
996 height=tile_height;
997 if ((tile_y+(ssize_t) tile_height) > (ssize_t) image->rows)
998 height=(size_t) (tile_height-(tile_y+tile_height-image->rows));
999 p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
1000 exception);
1001 if (p == (const Quantum *) NULL)
1002 {
1003 status=MagickFalse;
1004 break;
1005 }
1006 for (y=0; y < (ssize_t) width; y++)
1007 {
1008 register const Quantum
1009 *magick_restrict tile_pixels;
1010
1011 register ssize_t
1012 x;
1013
1014 if (status == MagickFalse)
1015 continue;
1016 q=QueueCacheViewAuthenticPixels(rotate_view,tile_y,(ssize_t) (y+
1017 rotate_image->rows-(tile_x+width)),height,1,exception);
1018 if (q == (Quantum *) NULL)
1019 {
1020 status=MagickFalse;
1021 continue;
1022 }
1023 tile_pixels=p+((width-1)-y)*GetPixelChannels(image);
1024 for (x=0; x < (ssize_t) height; x++)
1025 {
1026 register ssize_t
1027 i;
1028
1029 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1030 {
1031 PixelChannel channel = GetPixelChannelChannel(image,i);
1032 PixelTrait traits = GetPixelChannelTraits(image,channel);
1033 PixelTrait rotate_traits=GetPixelChannelTraits(rotate_image,
1034 channel);
1035 if ((traits == UndefinedPixelTrait) ||
1036 (rotate_traits == UndefinedPixelTrait))
1037 continue;
1038 SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
1039 }
1040 tile_pixels+=width*GetPixelChannels(image);
1041 q+=GetPixelChannels(rotate_image);
1042 }
1043 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1044 #pragma omp critical (MagickCore_IntegralRotateImage)
1045 #endif
1046 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
1047 if (sync == MagickFalse)
1048 status=MagickFalse;
1049 }
1050 }
1051 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1052 {
1053 MagickBooleanType
1054 proceed;
1055
1056 proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
1057 image->rows);
1058 if (proceed == MagickFalse)
1059 status=MagickFalse;
1060 }
1061 }
1062 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
1063 image->rows-1,image->rows);
1064 Swap(page.width,page.height);
1065 Swap(page.x,page.y);
1066 if (page.height != 0)
1067 page.y=(ssize_t) (page.height-rotate_image->rows-page.y);
1068 break;
1069 }
1070 default:
1071 break;
1072 }
1073 rotate_view=DestroyCacheView(rotate_view);
1074 image_view=DestroyCacheView(image_view);
1075 rotate_image->type=image->type;
1076 rotate_image->page=page;
1077 if (status == MagickFalse)
1078 rotate_image=DestroyImage(rotate_image);
1079 return(rotate_image);
1080 }
1081
1082 /*
1083 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1084 % %
1085 % %
1086 % %
1087 + X S h e a r I m a g e %
1088 % %
1089 % %
1090 % %
1091 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1092 %
1093 % XShearImage() shears the image in the X direction with a shear angle of
1094 % 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1095 % negative angles shear clockwise. Angles are measured relative to a vertical
1096 % Y-axis. X shears will widen an image creating 'empty' triangles on the left
1097 % and right sides of the source image.
1098 %
1099 % The format of the XShearImage method is:
1100 %
1101 % MagickBooleanType XShearImage(Image *image,const double degrees,
1102 % const size_t width,const size_t height,
1103 % const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1104 %
1105 % A description of each parameter follows.
1106 %
1107 % o image: the image.
1108 %
1109 % o degrees: A double representing the shearing angle along the X
1110 % axis.
1111 %
1112 % o width, height, x_offset, y_offset: Defines a region of the image
1113 % to shear.
1114 %
1115 % o exception: return any errors or warnings in this structure.
1116 %
1117 */
XShearImage(Image * image,const double degrees,const size_t width,const size_t height,const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo * exception)1118 static MagickBooleanType XShearImage(Image *image,const double degrees,
1119 const size_t width,const size_t height,const ssize_t x_offset,
1120 const ssize_t y_offset,ExceptionInfo *exception)
1121 {
1122 #define XShearImageTag "XShear/Image"
1123
1124 typedef enum
1125 {
1126 LEFT,
1127 RIGHT
1128 } ShearDirection;
1129
1130 CacheView
1131 *image_view;
1132
1133 MagickBooleanType
1134 status;
1135
1136 MagickOffsetType
1137 progress;
1138
1139 PixelInfo
1140 background;
1141
1142 ssize_t
1143 y;
1144
1145 /*
1146 X shear image.
1147 */
1148 assert(image != (Image *) NULL);
1149 assert(image->signature == MagickCoreSignature);
1150 if (image->debug != MagickFalse)
1151 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1152 status=MagickTrue;
1153 background=image->background_color;
1154 progress=0;
1155 image_view=AcquireAuthenticCacheView(image,exception);
1156 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1157 #pragma omp parallel for schedule(static) shared(progress,status) \
1158 magick_number_threads(image,image,height,1)
1159 #endif
1160 for (y=0; y < (ssize_t) height; y++)
1161 {
1162 PixelInfo
1163 pixel,
1164 source,
1165 destination;
1166
1167 double
1168 area,
1169 displacement;
1170
1171 register Quantum
1172 *magick_restrict p,
1173 *magick_restrict q;
1174
1175 register ssize_t
1176 i;
1177
1178 ShearDirection
1179 direction;
1180
1181 ssize_t
1182 step;
1183
1184 if (status == MagickFalse)
1185 continue;
1186 p=GetCacheViewAuthenticPixels(image_view,0,y_offset+y,image->columns,1,
1187 exception);
1188 if (p == (Quantum *) NULL)
1189 {
1190 status=MagickFalse;
1191 continue;
1192 }
1193 p+=x_offset*GetPixelChannels(image);
1194 displacement=degrees*(double) (y-height/2.0);
1195 if (displacement == 0.0)
1196 continue;
1197 if (displacement > 0.0)
1198 direction=RIGHT;
1199 else
1200 {
1201 displacement*=(-1.0);
1202 direction=LEFT;
1203 }
1204 step=(ssize_t) floor((double) displacement);
1205 area=(double) (displacement-step);
1206 step++;
1207 pixel=background;
1208 GetPixelInfo(image,&source);
1209 GetPixelInfo(image,&destination);
1210 switch (direction)
1211 {
1212 case LEFT:
1213 {
1214 /*
1215 Transfer pixels left-to-right.
1216 */
1217 if (step > x_offset)
1218 break;
1219 q=p-step*GetPixelChannels(image);
1220 for (i=0; i < (ssize_t) width; i++)
1221 {
1222 if ((x_offset+i) < step)
1223 {
1224 p+=GetPixelChannels(image);
1225 GetPixelInfoPixel(image,p,&pixel);
1226 q+=GetPixelChannels(image);
1227 continue;
1228 }
1229 GetPixelInfoPixel(image,p,&source);
1230 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1231 &source,(double) GetPixelAlpha(image,p),area,&destination);
1232 SetPixelViaPixelInfo(image,&destination,q);
1233 GetPixelInfoPixel(image,p,&pixel);
1234 p+=GetPixelChannels(image);
1235 q+=GetPixelChannels(image);
1236 }
1237 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1238 &background,(double) background.alpha,area,&destination);
1239 SetPixelViaPixelInfo(image,&destination,q);
1240 q+=GetPixelChannels(image);
1241 for (i=0; i < (step-1); i++)
1242 {
1243 SetPixelViaPixelInfo(image,&background,q);
1244 q+=GetPixelChannels(image);
1245 }
1246 break;
1247 }
1248 case RIGHT:
1249 {
1250 /*
1251 Transfer pixels right-to-left.
1252 */
1253 p+=width*GetPixelChannels(image);
1254 q=p+step*GetPixelChannels(image);
1255 for (i=0; i < (ssize_t) width; i++)
1256 {
1257 p-=GetPixelChannels(image);
1258 q-=GetPixelChannels(image);
1259 if ((size_t) (x_offset+width+step-i) > image->columns)
1260 continue;
1261 GetPixelInfoPixel(image,p,&source);
1262 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1263 &source,(double) GetPixelAlpha(image,p),area,&destination);
1264 SetPixelViaPixelInfo(image,&destination,q);
1265 GetPixelInfoPixel(image,p,&pixel);
1266 }
1267 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1268 &background,(double) background.alpha,area,&destination);
1269 q-=GetPixelChannels(image);
1270 SetPixelViaPixelInfo(image,&destination,q);
1271 for (i=0; i < (step-1); i++)
1272 {
1273 q-=GetPixelChannels(image);
1274 SetPixelViaPixelInfo(image,&background,q);
1275 }
1276 break;
1277 }
1278 }
1279 if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1280 status=MagickFalse;
1281 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1282 {
1283 MagickBooleanType
1284 proceed;
1285
1286 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1287 #pragma omp atomic
1288 #endif
1289 progress++;
1290 proceed=SetImageProgress(image,XShearImageTag,progress,height);
1291 if (proceed == MagickFalse)
1292 status=MagickFalse;
1293 }
1294 }
1295 image_view=DestroyCacheView(image_view);
1296 return(status);
1297 }
1298
1299 /*
1300 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1301 % %
1302 % %
1303 % %
1304 + Y S h e a r I m a g e %
1305 % %
1306 % %
1307 % %
1308 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1309 %
1310 % YShearImage shears the image in the Y direction with a shear angle of
1311 % 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1312 % negative angles shear clockwise. Angles are measured relative to a
1313 % horizontal X-axis. Y shears will increase the height of an image creating
1314 % 'empty' triangles on the top and bottom of the source image.
1315 %
1316 % The format of the YShearImage method is:
1317 %
1318 % MagickBooleanType YShearImage(Image *image,const double degrees,
1319 % const size_t width,const size_t height,
1320 % const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1321 %
1322 % A description of each parameter follows.
1323 %
1324 % o image: the image.
1325 %
1326 % o degrees: A double representing the shearing angle along the Y
1327 % axis.
1328 %
1329 % o width, height, x_offset, y_offset: Defines a region of the image
1330 % to shear.
1331 %
1332 % o exception: return any errors or warnings in this structure.
1333 %
1334 */
YShearImage(Image * image,const double degrees,const size_t width,const size_t height,const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo * exception)1335 static MagickBooleanType YShearImage(Image *image,const double degrees,
1336 const size_t width,const size_t height,const ssize_t x_offset,
1337 const ssize_t y_offset,ExceptionInfo *exception)
1338 {
1339 #define YShearImageTag "YShear/Image"
1340
1341 typedef enum
1342 {
1343 UP,
1344 DOWN
1345 } ShearDirection;
1346
1347 CacheView
1348 *image_view;
1349
1350 MagickBooleanType
1351 status;
1352
1353 MagickOffsetType
1354 progress;
1355
1356 PixelInfo
1357 background;
1358
1359 ssize_t
1360 x;
1361
1362 /*
1363 Y Shear image.
1364 */
1365 assert(image != (Image *) NULL);
1366 assert(image->signature == MagickCoreSignature);
1367 if (image->debug != MagickFalse)
1368 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1369 status=MagickTrue;
1370 progress=0;
1371 background=image->background_color;
1372 image_view=AcquireAuthenticCacheView(image,exception);
1373 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1374 #pragma omp parallel for schedule(static) shared(progress,status) \
1375 magick_number_threads(image,image,width,1)
1376 #endif
1377 for (x=0; x < (ssize_t) width; x++)
1378 {
1379 ssize_t
1380 step;
1381
1382 double
1383 area,
1384 displacement;
1385
1386 PixelInfo
1387 pixel,
1388 source,
1389 destination;
1390
1391 register Quantum
1392 *magick_restrict p,
1393 *magick_restrict q;
1394
1395 register ssize_t
1396 i;
1397
1398 ShearDirection
1399 direction;
1400
1401 if (status == MagickFalse)
1402 continue;
1403 p=GetCacheViewAuthenticPixels(image_view,x_offset+x,0,1,image->rows,
1404 exception);
1405 if (p == (Quantum *) NULL)
1406 {
1407 status=MagickFalse;
1408 continue;
1409 }
1410 p+=y_offset*GetPixelChannels(image);
1411 displacement=degrees*(double) (x-width/2.0);
1412 if (displacement == 0.0)
1413 continue;
1414 if (displacement > 0.0)
1415 direction=DOWN;
1416 else
1417 {
1418 displacement*=(-1.0);
1419 direction=UP;
1420 }
1421 step=(ssize_t) floor((double) displacement);
1422 area=(double) (displacement-step);
1423 step++;
1424 pixel=background;
1425 GetPixelInfo(image,&source);
1426 GetPixelInfo(image,&destination);
1427 switch (direction)
1428 {
1429 case UP:
1430 {
1431 /*
1432 Transfer pixels top-to-bottom.
1433 */
1434 if (step > y_offset)
1435 break;
1436 q=p-step*GetPixelChannels(image);
1437 for (i=0; i < (ssize_t) height; i++)
1438 {
1439 if ((y_offset+i) < step)
1440 {
1441 p+=GetPixelChannels(image);
1442 GetPixelInfoPixel(image,p,&pixel);
1443 q+=GetPixelChannels(image);
1444 continue;
1445 }
1446 GetPixelInfoPixel(image,p,&source);
1447 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1448 &source,(double) GetPixelAlpha(image,p),area,
1449 &destination);
1450 SetPixelViaPixelInfo(image,&destination,q);
1451 GetPixelInfoPixel(image,p,&pixel);
1452 p+=GetPixelChannels(image);
1453 q+=GetPixelChannels(image);
1454 }
1455 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1456 &background,(double) background.alpha,area,&destination);
1457 SetPixelViaPixelInfo(image,&destination,q);
1458 q+=GetPixelChannels(image);
1459 for (i=0; i < (step-1); i++)
1460 {
1461 SetPixelViaPixelInfo(image,&background,q);
1462 q+=GetPixelChannels(image);
1463 }
1464 break;
1465 }
1466 case DOWN:
1467 {
1468 /*
1469 Transfer pixels bottom-to-top.
1470 */
1471 p+=height*GetPixelChannels(image);
1472 q=p+step*GetPixelChannels(image);
1473 for (i=0; i < (ssize_t) height; i++)
1474 {
1475 p-=GetPixelChannels(image);
1476 q-=GetPixelChannels(image);
1477 if ((size_t) (y_offset+height+step-i) > image->rows)
1478 continue;
1479 GetPixelInfoPixel(image,p,&source);
1480 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1481 &source,(double) GetPixelAlpha(image,p),area,
1482 &destination);
1483 SetPixelViaPixelInfo(image,&destination,q);
1484 GetPixelInfoPixel(image,p,&pixel);
1485 }
1486 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1487 &background,(double) background.alpha,area,&destination);
1488 q-=GetPixelChannels(image);
1489 SetPixelViaPixelInfo(image,&destination,q);
1490 for (i=0; i < (step-1); i++)
1491 {
1492 q-=GetPixelChannels(image);
1493 SetPixelViaPixelInfo(image,&background,q);
1494 }
1495 break;
1496 }
1497 }
1498 if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1499 status=MagickFalse;
1500 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1501 {
1502 MagickBooleanType
1503 proceed;
1504
1505 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1506 #pragma omp atomic
1507 #endif
1508 progress++;
1509 proceed=SetImageProgress(image,YShearImageTag,progress,image->rows);
1510 if (proceed == MagickFalse)
1511 status=MagickFalse;
1512 }
1513 }
1514 image_view=DestroyCacheView(image_view);
1515 return(status);
1516 }
1517
1518 /*
1519 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1520 % %
1521 % %
1522 % %
1523 % S h e a r I m a g e %
1524 % %
1525 % %
1526 % %
1527 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1528 %
1529 % ShearImage() creates a new image that is a shear_image copy of an existing
1530 % one. Shearing slides one edge of an image along the X or Y axis, creating
1531 % a parallelogram. An X direction shear slides an edge along the X axis,
1532 % while a Y direction shear slides an edge along the Y axis. The amount of
1533 % the shear is controlled by a shear angle. For X direction shears, x_shear
1534 % is measured relative to the Y axis, and similarly, for Y direction shears
1535 % y_shear is measured relative to the X axis. Empty triangles left over from
1536 % shearing the image are filled with the background color defined by member
1537 % 'background_color' of the image.. ShearImage() allocates the memory
1538 % necessary for the new Image structure and returns a pointer to the new image.
1539 %
1540 % ShearImage() is based on the paper "A Fast Algorithm for General Raster
1541 % Rotatation" by Alan W. Paeth.
1542 %
1543 % The format of the ShearImage method is:
1544 %
1545 % Image *ShearImage(const Image *image,const double x_shear,
1546 % const double y_shear,ExceptionInfo *exception)
1547 %
1548 % A description of each parameter follows.
1549 %
1550 % o image: the image.
1551 %
1552 % o x_shear, y_shear: Specifies the number of degrees to shear the image.
1553 %
1554 % o exception: return any errors or warnings in this structure.
1555 %
1556 */
ShearImage(const Image * image,const double x_shear,const double y_shear,ExceptionInfo * exception)1557 MagickExport Image *ShearImage(const Image *image,const double x_shear,
1558 const double y_shear,ExceptionInfo *exception)
1559 {
1560 Image
1561 *integral_image,
1562 *shear_image;
1563
1564 MagickBooleanType
1565 status;
1566
1567 PointInfo
1568 shear;
1569
1570 RectangleInfo
1571 border_info,
1572 bounds;
1573
1574 assert(image != (Image *) NULL);
1575 assert(image->signature == MagickCoreSignature);
1576 if (image->debug != MagickFalse)
1577 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1578 assert(exception != (ExceptionInfo *) NULL);
1579 assert(exception->signature == MagickCoreSignature);
1580 if ((x_shear != 0.0) && (fmod(x_shear,90.0) == 0.0))
1581 ThrowImageException(ImageError,"AngleIsDiscontinuous");
1582 if ((y_shear != 0.0) && (fmod(y_shear,90.0) == 0.0))
1583 ThrowImageException(ImageError,"AngleIsDiscontinuous");
1584 /*
1585 Initialize shear angle.
1586 */
1587 integral_image=CloneImage(image,0,0,MagickTrue,exception);
1588 if (integral_image == (Image *) NULL)
1589 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1590 shear.x=(-tan(DegreesToRadians(fmod(x_shear,360.0))));
1591 shear.y=tan(DegreesToRadians(fmod(y_shear,360.0)));
1592 if ((shear.x == 0.0) && (shear.y == 0.0))
1593 return(integral_image);
1594 if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1595 {
1596 integral_image=DestroyImage(integral_image);
1597 return(integral_image);
1598 }
1599 if (integral_image->alpha_trait == UndefinedPixelTrait)
1600 (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1601 /*
1602 Compute image size.
1603 */
1604 bounds.width=image->columns+(ssize_t) floor(fabs(shear.x)*image->rows+0.5);
1605 bounds.x=(ssize_t) ceil((double) image->columns+((fabs(shear.x)*image->rows)-
1606 image->columns)/2.0-0.5);
1607 bounds.y=(ssize_t) ceil((double) image->rows+((fabs(shear.y)*bounds.width)-
1608 image->rows)/2.0-0.5);
1609 /*
1610 Surround image with border.
1611 */
1612 integral_image->border_color=integral_image->background_color;
1613 integral_image->compose=CopyCompositeOp;
1614 border_info.width=(size_t) bounds.x;
1615 border_info.height=(size_t) bounds.y;
1616 shear_image=BorderImage(integral_image,&border_info,image->compose,exception);
1617 integral_image=DestroyImage(integral_image);
1618 if (shear_image == (Image *) NULL)
1619 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1620 /*
1621 Shear the image.
1622 */
1623 if (shear_image->alpha_trait == UndefinedPixelTrait)
1624 (void) SetImageAlphaChannel(shear_image,OpaqueAlphaChannel,exception);
1625 status=XShearImage(shear_image,shear.x,image->columns,image->rows,bounds.x,
1626 (ssize_t) (shear_image->rows-image->rows)/2,exception);
1627 if (status == MagickFalse)
1628 {
1629 shear_image=DestroyImage(shear_image);
1630 return((Image *) NULL);
1631 }
1632 status=YShearImage(shear_image,shear.y,bounds.width,image->rows,(ssize_t)
1633 (shear_image->columns-bounds.width)/2,bounds.y,exception);
1634 if (status == MagickFalse)
1635 {
1636 shear_image=DestroyImage(shear_image);
1637 return((Image *) NULL);
1638 }
1639 status=CropToFitImage(&shear_image,shear.x,shear.y,(MagickRealType)
1640 image->columns,(MagickRealType) image->rows,MagickFalse,exception);
1641 shear_image->alpha_trait=image->alpha_trait;
1642 shear_image->compose=image->compose;
1643 shear_image->page.width=0;
1644 shear_image->page.height=0;
1645 if (status == MagickFalse)
1646 shear_image=DestroyImage(shear_image);
1647 return(shear_image);
1648 }
1649
1650 /*
1651 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1652 % %
1653 % %
1654 % %
1655 % S h e a r R o t a t e I m a g e %
1656 % %
1657 % %
1658 % %
1659 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1660 %
1661 % ShearRotateImage() creates a new image that is a rotated copy of an existing
1662 % one. Positive angles rotate counter-clockwise (right-hand rule), while
1663 % negative angles rotate clockwise. Rotated images are usually larger than
1664 % the originals and have 'empty' triangular corners. X axis. Empty
1665 % triangles left over from shearing the image are filled with the background
1666 % color defined by member 'background_color' of the image. ShearRotateImage
1667 % allocates the memory necessary for the new Image structure and returns a
1668 % pointer to the new image.
1669 %
1670 % ShearRotateImage() is based on the paper "A Fast Algorithm for General
1671 % Raster Rotatation" by Alan W. Paeth. ShearRotateImage is adapted from a
1672 % similar method based on the Paeth paper written by Michael Halle of the
1673 % Spatial Imaging Group, MIT Media Lab.
1674 %
1675 % The format of the ShearRotateImage method is:
1676 %
1677 % Image *ShearRotateImage(const Image *image,const double degrees,
1678 % ExceptionInfo *exception)
1679 %
1680 % A description of each parameter follows.
1681 %
1682 % o image: the image.
1683 %
1684 % o degrees: Specifies the number of degrees to rotate the image.
1685 %
1686 % o exception: return any errors or warnings in this structure.
1687 %
1688 */
ShearRotateImage(const Image * image,const double degrees,ExceptionInfo * exception)1689 MagickExport Image *ShearRotateImage(const Image *image,const double degrees,
1690 ExceptionInfo *exception)
1691 {
1692 Image
1693 *integral_image,
1694 *rotate_image;
1695
1696 MagickBooleanType
1697 status;
1698
1699 MagickRealType
1700 angle;
1701
1702 PointInfo
1703 shear;
1704
1705 RectangleInfo
1706 border_info,
1707 bounds;
1708
1709 size_t
1710 height,
1711 rotations,
1712 shear_width,
1713 width;
1714
1715 /*
1716 Adjust rotation angle.
1717 */
1718 assert(image != (Image *) NULL);
1719 assert(image->signature == MagickCoreSignature);
1720 if (image->debug != MagickFalse)
1721 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1722 assert(exception != (ExceptionInfo *) NULL);
1723 assert(exception->signature == MagickCoreSignature);
1724 angle=fmod(degrees,360.0);
1725 if (angle < -45.0)
1726 angle+=360.0;
1727 for (rotations=0; angle > 45.0; rotations++)
1728 angle-=90.0;
1729 rotations%=4;
1730 /*
1731 Calculate shear equations.
1732 */
1733 integral_image=IntegralRotateImage(image,rotations,exception);
1734 if (integral_image == (Image *) NULL)
1735 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1736 shear.x=(-tan((double) DegreesToRadians(angle)/2.0));
1737 shear.y=sin((double) DegreesToRadians(angle));
1738 if ((shear.x == 0.0) && (shear.y == 0.0))
1739 return(integral_image);
1740 if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1741 {
1742 integral_image=DestroyImage(integral_image);
1743 return(integral_image);
1744 }
1745 if (integral_image->alpha_trait == UndefinedPixelTrait)
1746 (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1747 /*
1748 Compute maximum bounds for 3 shear operations.
1749 */
1750 width=integral_image->columns;
1751 height=integral_image->rows;
1752 bounds.width=(size_t) floor(fabs((double) height*shear.x)+width+0.5);
1753 bounds.height=(size_t) floor(fabs((double) bounds.width*shear.y)+height+0.5);
1754 shear_width=(size_t) floor(fabs((double) bounds.height*shear.x)+
1755 bounds.width+0.5);
1756 bounds.x=(ssize_t) floor((double) ((shear_width > bounds.width) ? width :
1757 bounds.width-shear_width+2)/2.0+0.5);
1758 bounds.y=(ssize_t) floor(((double) bounds.height-height+2)/2.0+0.5);
1759 /*
1760 Surround image with a border.
1761 */
1762 integral_image->border_color=integral_image->background_color;
1763 integral_image->compose=CopyCompositeOp;
1764 border_info.width=(size_t) bounds.x;
1765 border_info.height=(size_t) bounds.y;
1766 rotate_image=BorderImage(integral_image,&border_info,image->compose,
1767 exception);
1768 integral_image=DestroyImage(integral_image);
1769 if (rotate_image == (Image *) NULL)
1770 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1771 /*
1772 Rotate the image.
1773 */
1774 status=XShearImage(rotate_image,shear.x,width,height,bounds.x,(ssize_t)
1775 (rotate_image->rows-height)/2,exception);
1776 if (status == MagickFalse)
1777 {
1778 rotate_image=DestroyImage(rotate_image);
1779 return((Image *) NULL);
1780 }
1781 status=YShearImage(rotate_image,shear.y,bounds.width,height,(ssize_t)
1782 (rotate_image->columns-bounds.width)/2,bounds.y,exception);
1783 if (status == MagickFalse)
1784 {
1785 rotate_image=DestroyImage(rotate_image);
1786 return((Image *) NULL);
1787 }
1788 status=XShearImage(rotate_image,shear.x,bounds.width,bounds.height,(ssize_t)
1789 (rotate_image->columns-bounds.width)/2,(ssize_t) (rotate_image->rows-
1790 bounds.height)/2,exception);
1791 if (status == MagickFalse)
1792 {
1793 rotate_image=DestroyImage(rotate_image);
1794 return((Image *) NULL);
1795 }
1796 status=CropToFitImage(&rotate_image,shear.x,shear.y,(MagickRealType) width,
1797 (MagickRealType) height,MagickTrue,exception);
1798 rotate_image->alpha_trait=image->alpha_trait;
1799 rotate_image->compose=image->compose;
1800 rotate_image->page.width=0;
1801 rotate_image->page.height=0;
1802 if (status == MagickFalse)
1803 rotate_image=DestroyImage(rotate_image);
1804 return(rotate_image);
1805 }
1806