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 1999-2021 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 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=CastDoubleToLong(ceil(min.x-0.5));
167 geometry.y=CastDoubleToLong(ceil(min.y-0.5));
168 geometry.width=(size_t) CastDoubleToLong(floor(max.x-min.x+0.5));
169 geometry.height=(size_t) CastDoubleToLong(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 MatrixInfo
223 *p,
224 *q;
225
226 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 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 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 const Quantum
388 *magick_restrict p;
389
390 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 const Quantum
445 *magick_restrict p;
446
447 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 const Quantum
526 *magick_restrict p;
527
528 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 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 switch (rotations)
734 {
735 case 0:
736 default:
737 {
738 rotate_image=CloneImage(image,0,0,MagickTrue,exception);
739 break;
740 }
741 case 2:
742 {
743 rotate_image=CloneImage(image,image->columns,image->rows,MagickTrue,
744 exception);
745 break;
746 }
747 case 1:
748 case 3:
749 {
750 rotate_image=CloneImage(image,image->rows,image->columns,MagickTrue,
751 exception);
752 break;
753 }
754 }
755 if (rotate_image == (Image *) NULL)
756 return((Image *) NULL);
757 if (rotations == 0)
758 return(rotate_image);
759 /*
760 Integral rotate the image.
761 */
762 status=MagickTrue;
763 progress=0;
764 image_view=AcquireVirtualCacheView(image,exception);
765 rotate_view=AcquireAuthenticCacheView(rotate_image,exception);
766 switch (rotations)
767 {
768 case 1:
769 {
770 size_t
771 tile_height,
772 tile_width;
773
774 ssize_t
775 tile_y;
776
777 /*
778 Rotate 90 degrees.
779 */
780 GetPixelCacheTileSize(image,&tile_width,&tile_height);
781 tile_width=image->columns;
782 #if defined(MAGICKCORE_OPENMP_SUPPORT)
783 #pragma omp parallel for schedule(static) shared(status) \
784 magick_number_threads(image,rotate_image,image->rows/tile_height,1)
785 #endif
786 for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
787 {
788 ssize_t
789 tile_x;
790
791 if (status == MagickFalse)
792 continue;
793 tile_x=0;
794 for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
795 {
796 MagickBooleanType
797 sync;
798
799 const Quantum
800 *magick_restrict p;
801
802 Quantum
803 *magick_restrict q;
804
805 ssize_t
806 y;
807
808 size_t
809 height,
810 width;
811
812 width=tile_width;
813 if ((tile_width+tile_x) > image->columns)
814 width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
815 height=tile_height;
816 if ((tile_height+tile_y) > image->rows)
817 height=(size_t) (tile_height-(tile_y+tile_height-image->rows));
818 p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
819 exception);
820 if (p == (const Quantum *) NULL)
821 {
822 status=MagickFalse;
823 break;
824 }
825 for (y=0; y < (ssize_t) width; y++)
826 {
827 const Quantum
828 *magick_restrict tile_pixels;
829
830 ssize_t
831 x;
832
833 if (status == MagickFalse)
834 continue;
835 q=QueueCacheViewAuthenticPixels(rotate_view,(ssize_t)
836 (rotate_image->columns-(tile_y+height)),y+tile_x,height,1,
837 exception);
838 if (q == (Quantum *) NULL)
839 {
840 status=MagickFalse;
841 continue;
842 }
843 tile_pixels=p+((height-1)*width+y)*GetPixelChannels(image);
844 for (x=0; x < (ssize_t) height; x++)
845 {
846 ssize_t
847 i;
848
849 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
850 {
851 PixelChannel channel = GetPixelChannelChannel(image,i);
852 PixelTrait traits = GetPixelChannelTraits(image,channel);
853 PixelTrait rotate_traits = GetPixelChannelTraits(rotate_image,
854 channel);
855 if ((traits == UndefinedPixelTrait) ||
856 (rotate_traits == UndefinedPixelTrait))
857 continue;
858 SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
859 }
860 tile_pixels-=width*GetPixelChannels(image);
861 q+=GetPixelChannels(rotate_image);
862 }
863 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
864 if (sync == MagickFalse)
865 status=MagickFalse;
866 }
867 }
868 if (image->progress_monitor != (MagickProgressMonitor) NULL)
869 {
870 MagickBooleanType
871 proceed;
872
873 proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
874 image->rows);
875 if (proceed == MagickFalse)
876 status=MagickFalse;
877 }
878 }
879 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
880 image->rows-1,image->rows);
881 Swap(page.width,page.height);
882 Swap(page.x,page.y);
883 if (page.width != 0)
884 page.x=(ssize_t) (page.width-rotate_image->columns-page.x);
885 break;
886 }
887 case 2:
888 {
889 ssize_t
890 y;
891
892 /*
893 Rotate 180 degrees.
894 */
895 #if defined(MAGICKCORE_OPENMP_SUPPORT)
896 #pragma omp parallel for schedule(static) shared(status) \
897 magick_number_threads(image,rotate_image,image->rows,1)
898 #endif
899 for (y=0; y < (ssize_t) image->rows; y++)
900 {
901 MagickBooleanType
902 sync;
903
904 const Quantum
905 *magick_restrict p;
906
907 Quantum
908 *magick_restrict q;
909
910 ssize_t
911 x;
912
913 if (status == MagickFalse)
914 continue;
915 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
916 q=QueueCacheViewAuthenticPixels(rotate_view,0,(ssize_t) (image->rows-y-
917 1),image->columns,1,exception);
918 if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
919 {
920 status=MagickFalse;
921 continue;
922 }
923 q+=GetPixelChannels(rotate_image)*image->columns;
924 for (x=0; x < (ssize_t) image->columns; x++)
925 {
926 ssize_t
927 i;
928
929 q-=GetPixelChannels(rotate_image);
930 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
931 {
932 PixelChannel channel = GetPixelChannelChannel(image,i);
933 PixelTrait traits = GetPixelChannelTraits(image,channel);
934 PixelTrait rotate_traits = GetPixelChannelTraits(rotate_image,
935 channel);
936 if ((traits == UndefinedPixelTrait) ||
937 (rotate_traits == UndefinedPixelTrait))
938 continue;
939 SetPixelChannel(rotate_image,channel,p[i],q);
940 }
941 p+=GetPixelChannels(image);
942 }
943 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
944 if (sync == MagickFalse)
945 status=MagickFalse;
946 if (image->progress_monitor != (MagickProgressMonitor) NULL)
947 {
948 MagickBooleanType
949 proceed;
950
951 proceed=SetImageProgress(image,RotateImageTag,progress++,
952 image->rows);
953 if (proceed == MagickFalse)
954 status=MagickFalse;
955 }
956 }
957 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
958 image->rows-1,image->rows);
959 if (page.width != 0)
960 page.x=(ssize_t) (page.width-rotate_image->columns-page.x);
961 if (page.height != 0)
962 page.y=(ssize_t) (page.height-rotate_image->rows-page.y);
963 break;
964 }
965 case 3:
966 {
967 size_t
968 tile_height,
969 tile_width;
970
971 ssize_t
972 tile_y;
973
974 /*
975 Rotate 270 degrees.
976 */
977 GetPixelCacheTileSize(image,&tile_width,&tile_height);
978 tile_width=image->columns;
979 #if defined(MAGICKCORE_OPENMP_SUPPORT)
980 #pragma omp parallel for schedule(static) shared(status) \
981 magick_number_threads(image,rotate_image,image->rows/tile_height,1)
982 #endif
983 for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
984 {
985 ssize_t
986 tile_x;
987
988 if (status == MagickFalse)
989 continue;
990 tile_x=0;
991 for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
992 {
993 MagickBooleanType
994 sync;
995
996 const Quantum
997 *magick_restrict p;
998
999 Quantum
1000 *magick_restrict q;
1001
1002 ssize_t
1003 y;
1004
1005 size_t
1006 height,
1007 width;
1008
1009 width=tile_width;
1010 if ((tile_width+tile_x) > image->columns)
1011 width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
1012 height=tile_height;
1013 if ((tile_height+tile_y) > image->rows)
1014 height=(size_t) (tile_height-(tile_y+tile_height-image->rows));
1015 p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
1016 exception);
1017 if (p == (const Quantum *) NULL)
1018 {
1019 status=MagickFalse;
1020 break;
1021 }
1022 for (y=0; y < (ssize_t) width; y++)
1023 {
1024 const Quantum
1025 *magick_restrict tile_pixels;
1026
1027 ssize_t
1028 x;
1029
1030 if (status == MagickFalse)
1031 continue;
1032 q=QueueCacheViewAuthenticPixels(rotate_view,tile_y,(ssize_t) (y+
1033 rotate_image->rows-(tile_x+width)),height,1,exception);
1034 if (q == (Quantum *) NULL)
1035 {
1036 status=MagickFalse;
1037 continue;
1038 }
1039 tile_pixels=p+((width-1)-y)*GetPixelChannels(image);
1040 for (x=0; x < (ssize_t) height; x++)
1041 {
1042 ssize_t
1043 i;
1044
1045 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1046 {
1047 PixelChannel channel = GetPixelChannelChannel(image,i);
1048 PixelTrait traits = GetPixelChannelTraits(image,channel);
1049 PixelTrait rotate_traits = GetPixelChannelTraits(rotate_image,
1050 channel);
1051 if ((traits == UndefinedPixelTrait) ||
1052 (rotate_traits == UndefinedPixelTrait))
1053 continue;
1054 SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
1055 }
1056 tile_pixels+=width*GetPixelChannels(image);
1057 q+=GetPixelChannels(rotate_image);
1058 }
1059 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1060 #pragma omp critical (MagickCore_IntegralRotateImage)
1061 #endif
1062 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
1063 if (sync == MagickFalse)
1064 status=MagickFalse;
1065 }
1066 }
1067 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1068 {
1069 MagickBooleanType
1070 proceed;
1071
1072 proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
1073 image->rows);
1074 if (proceed == MagickFalse)
1075 status=MagickFalse;
1076 }
1077 }
1078 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
1079 image->rows-1,image->rows);
1080 Swap(page.width,page.height);
1081 Swap(page.x,page.y);
1082 if (page.height != 0)
1083 page.y=(ssize_t) (page.height-rotate_image->rows-page.y);
1084 break;
1085 }
1086 default:
1087 break;
1088 }
1089 rotate_view=DestroyCacheView(rotate_view);
1090 image_view=DestroyCacheView(image_view);
1091 rotate_image->type=image->type;
1092 rotate_image->page=page;
1093 if (status == MagickFalse)
1094 rotate_image=DestroyImage(rotate_image);
1095 return(rotate_image);
1096 }
1097
1098 /*
1099 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1100 % %
1101 % %
1102 % %
1103 + X S h e a r I m a g e %
1104 % %
1105 % %
1106 % %
1107 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1108 %
1109 % XShearImage() shears the image in the X direction with a shear angle of
1110 % 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1111 % negative angles shear clockwise. Angles are measured relative to a vertical
1112 % Y-axis. X shears will widen an image creating 'empty' triangles on the left
1113 % and right sides of the source image.
1114 %
1115 % The format of the XShearImage method is:
1116 %
1117 % MagickBooleanType XShearImage(Image *image,const double degrees,
1118 % const size_t width,const size_t height,
1119 % const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1120 %
1121 % A description of each parameter follows.
1122 %
1123 % o image: the image.
1124 %
1125 % o degrees: A double representing the shearing angle along the X
1126 % axis.
1127 %
1128 % o width, height, x_offset, y_offset: Defines a region of the image
1129 % to shear.
1130 %
1131 % o exception: return any errors or warnings in this structure.
1132 %
1133 */
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)1134 static MagickBooleanType XShearImage(Image *image,const double degrees,
1135 const size_t width,const size_t height,const ssize_t x_offset,
1136 const ssize_t y_offset,ExceptionInfo *exception)
1137 {
1138 #define XShearImageTag "XShear/Image"
1139
1140 typedef enum
1141 {
1142 LEFT,
1143 RIGHT
1144 } ShearDirection;
1145
1146 CacheView
1147 *image_view;
1148
1149 MagickBooleanType
1150 status;
1151
1152 MagickOffsetType
1153 progress;
1154
1155 PixelInfo
1156 background;
1157
1158 ssize_t
1159 y;
1160
1161 /*
1162 X shear image.
1163 */
1164 assert(image != (Image *) NULL);
1165 assert(image->signature == MagickCoreSignature);
1166 if (image->debug != MagickFalse)
1167 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1168 status=MagickTrue;
1169 background=image->background_color;
1170 progress=0;
1171 image_view=AcquireAuthenticCacheView(image,exception);
1172 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1173 #pragma omp parallel for schedule(static) shared(progress,status) \
1174 magick_number_threads(image,image,height,1)
1175 #endif
1176 for (y=0; y < (ssize_t) height; y++)
1177 {
1178 PixelInfo
1179 pixel,
1180 source,
1181 destination;
1182
1183 double
1184 area,
1185 displacement;
1186
1187 Quantum
1188 *magick_restrict p,
1189 *magick_restrict q;
1190
1191 ssize_t
1192 i;
1193
1194 ShearDirection
1195 direction;
1196
1197 ssize_t
1198 step;
1199
1200 if (status == MagickFalse)
1201 continue;
1202 p=GetCacheViewAuthenticPixels(image_view,0,y_offset+y,image->columns,1,
1203 exception);
1204 if (p == (Quantum *) NULL)
1205 {
1206 status=MagickFalse;
1207 continue;
1208 }
1209 p+=x_offset*GetPixelChannels(image);
1210 displacement=degrees*(double) (y-height/2.0);
1211 if (displacement == 0.0)
1212 continue;
1213 if (displacement > 0.0)
1214 direction=RIGHT;
1215 else
1216 {
1217 displacement*=(-1.0);
1218 direction=LEFT;
1219 }
1220 step=CastDoubleToLong(floor((double) displacement));
1221 area=(double) (displacement-step);
1222 step++;
1223 pixel=background;
1224 GetPixelInfo(image,&source);
1225 GetPixelInfo(image,&destination);
1226 switch (direction)
1227 {
1228 case LEFT:
1229 {
1230 /*
1231 Transfer pixels left-to-right.
1232 */
1233 if (step > x_offset)
1234 break;
1235 q=p-step*GetPixelChannels(image);
1236 for (i=0; i < (ssize_t) width; i++)
1237 {
1238 if ((x_offset+i) < step)
1239 {
1240 p+=GetPixelChannels(image);
1241 GetPixelInfoPixel(image,p,&pixel);
1242 q+=GetPixelChannels(image);
1243 continue;
1244 }
1245 GetPixelInfoPixel(image,p,&source);
1246 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1247 &source,(double) GetPixelAlpha(image,p),area,&destination);
1248 SetPixelViaPixelInfo(image,&destination,q);
1249 GetPixelInfoPixel(image,p,&pixel);
1250 p+=GetPixelChannels(image);
1251 q+=GetPixelChannels(image);
1252 }
1253 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1254 &background,(double) background.alpha,area,&destination);
1255 SetPixelViaPixelInfo(image,&destination,q);
1256 q+=GetPixelChannels(image);
1257 for (i=0; i < (step-1); i++)
1258 {
1259 SetPixelViaPixelInfo(image,&background,q);
1260 q+=GetPixelChannels(image);
1261 }
1262 break;
1263 }
1264 case RIGHT:
1265 {
1266 /*
1267 Transfer pixels right-to-left.
1268 */
1269 p+=width*GetPixelChannels(image);
1270 q=p+step*GetPixelChannels(image);
1271 for (i=0; i < (ssize_t) width; i++)
1272 {
1273 p-=GetPixelChannels(image);
1274 q-=GetPixelChannels(image);
1275 if ((size_t) (x_offset+width+step-i) > image->columns)
1276 continue;
1277 GetPixelInfoPixel(image,p,&source);
1278 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1279 &source,(double) GetPixelAlpha(image,p),area,&destination);
1280 SetPixelViaPixelInfo(image,&destination,q);
1281 GetPixelInfoPixel(image,p,&pixel);
1282 }
1283 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1284 &background,(double) background.alpha,area,&destination);
1285 q-=GetPixelChannels(image);
1286 SetPixelViaPixelInfo(image,&destination,q);
1287 for (i=0; i < (step-1); i++)
1288 {
1289 q-=GetPixelChannels(image);
1290 SetPixelViaPixelInfo(image,&background,q);
1291 }
1292 break;
1293 }
1294 }
1295 if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1296 status=MagickFalse;
1297 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1298 {
1299 MagickBooleanType
1300 proceed;
1301
1302 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1303 #pragma omp atomic
1304 #endif
1305 progress++;
1306 proceed=SetImageProgress(image,XShearImageTag,progress,height);
1307 if (proceed == MagickFalse)
1308 status=MagickFalse;
1309 }
1310 }
1311 image_view=DestroyCacheView(image_view);
1312 return(status);
1313 }
1314
1315 /*
1316 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1317 % %
1318 % %
1319 % %
1320 + Y S h e a r I m a g e %
1321 % %
1322 % %
1323 % %
1324 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1325 %
1326 % YShearImage shears the image in the Y direction with a shear angle of
1327 % 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1328 % negative angles shear clockwise. Angles are measured relative to a
1329 % horizontal X-axis. Y shears will increase the height of an image creating
1330 % 'empty' triangles on the top and bottom of the source image.
1331 %
1332 % The format of the YShearImage method is:
1333 %
1334 % MagickBooleanType YShearImage(Image *image,const double degrees,
1335 % const size_t width,const size_t height,
1336 % const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1337 %
1338 % A description of each parameter follows.
1339 %
1340 % o image: the image.
1341 %
1342 % o degrees: A double representing the shearing angle along the Y
1343 % axis.
1344 %
1345 % o width, height, x_offset, y_offset: Defines a region of the image
1346 % to shear.
1347 %
1348 % o exception: return any errors or warnings in this structure.
1349 %
1350 */
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)1351 static MagickBooleanType YShearImage(Image *image,const double degrees,
1352 const size_t width,const size_t height,const ssize_t x_offset,
1353 const ssize_t y_offset,ExceptionInfo *exception)
1354 {
1355 #define YShearImageTag "YShear/Image"
1356
1357 typedef enum
1358 {
1359 UP,
1360 DOWN
1361 } ShearDirection;
1362
1363 CacheView
1364 *image_view;
1365
1366 MagickBooleanType
1367 status;
1368
1369 MagickOffsetType
1370 progress;
1371
1372 PixelInfo
1373 background;
1374
1375 ssize_t
1376 x;
1377
1378 /*
1379 Y Shear image.
1380 */
1381 assert(image != (Image *) NULL);
1382 assert(image->signature == MagickCoreSignature);
1383 if (image->debug != MagickFalse)
1384 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1385 status=MagickTrue;
1386 progress=0;
1387 background=image->background_color;
1388 image_view=AcquireAuthenticCacheView(image,exception);
1389 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1390 #pragma omp parallel for schedule(static) shared(progress,status) \
1391 magick_number_threads(image,image,width,1)
1392 #endif
1393 for (x=0; x < (ssize_t) width; x++)
1394 {
1395 double
1396 area,
1397 displacement;
1398
1399 PixelInfo
1400 pixel,
1401 source,
1402 destination;
1403
1404 Quantum
1405 *magick_restrict p,
1406 *magick_restrict q;
1407
1408 ssize_t
1409 i;
1410
1411 ShearDirection
1412 direction;
1413
1414 ssize_t
1415 step;
1416
1417 if (status == MagickFalse)
1418 continue;
1419 p=GetCacheViewAuthenticPixels(image_view,x_offset+x,0,1,image->rows,
1420 exception);
1421 if (p == (Quantum *) NULL)
1422 {
1423 status=MagickFalse;
1424 continue;
1425 }
1426 p+=y_offset*GetPixelChannels(image);
1427 displacement=degrees*(double) (x-width/2.0);
1428 if (displacement == 0.0)
1429 continue;
1430 if (displacement > 0.0)
1431 direction=DOWN;
1432 else
1433 {
1434 displacement*=(-1.0);
1435 direction=UP;
1436 }
1437 step=CastDoubleToLong(floor((double) displacement));
1438 area=(double) (displacement-step);
1439 step++;
1440 pixel=background;
1441 GetPixelInfo(image,&source);
1442 GetPixelInfo(image,&destination);
1443 switch (direction)
1444 {
1445 case UP:
1446 {
1447 /*
1448 Transfer pixels top-to-bottom.
1449 */
1450 if (step > y_offset)
1451 break;
1452 q=p-step*GetPixelChannels(image);
1453 for (i=0; i < (ssize_t) height; i++)
1454 {
1455 if ((y_offset+i) < step)
1456 {
1457 p+=GetPixelChannels(image);
1458 GetPixelInfoPixel(image,p,&pixel);
1459 q+=GetPixelChannels(image);
1460 continue;
1461 }
1462 GetPixelInfoPixel(image,p,&source);
1463 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1464 &source,(double) GetPixelAlpha(image,p),area,
1465 &destination);
1466 SetPixelViaPixelInfo(image,&destination,q);
1467 GetPixelInfoPixel(image,p,&pixel);
1468 p+=GetPixelChannels(image);
1469 q+=GetPixelChannels(image);
1470 }
1471 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1472 &background,(double) background.alpha,area,&destination);
1473 SetPixelViaPixelInfo(image,&destination,q);
1474 q+=GetPixelChannels(image);
1475 for (i=0; i < (step-1); i++)
1476 {
1477 SetPixelViaPixelInfo(image,&background,q);
1478 q+=GetPixelChannels(image);
1479 }
1480 break;
1481 }
1482 case DOWN:
1483 {
1484 /*
1485 Transfer pixels bottom-to-top.
1486 */
1487 p+=height*GetPixelChannels(image);
1488 q=p+step*GetPixelChannels(image);
1489 for (i=0; i < (ssize_t) height; i++)
1490 {
1491 p-=GetPixelChannels(image);
1492 q-=GetPixelChannels(image);
1493 if ((size_t) (y_offset+height+step-i) > image->rows)
1494 continue;
1495 GetPixelInfoPixel(image,p,&source);
1496 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1497 &source,(double) GetPixelAlpha(image,p),area,
1498 &destination);
1499 SetPixelViaPixelInfo(image,&destination,q);
1500 GetPixelInfoPixel(image,p,&pixel);
1501 }
1502 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1503 &background,(double) background.alpha,area,&destination);
1504 q-=GetPixelChannels(image);
1505 SetPixelViaPixelInfo(image,&destination,q);
1506 for (i=0; i < (step-1); i++)
1507 {
1508 q-=GetPixelChannels(image);
1509 SetPixelViaPixelInfo(image,&background,q);
1510 }
1511 break;
1512 }
1513 }
1514 if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1515 status=MagickFalse;
1516 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1517 {
1518 MagickBooleanType
1519 proceed;
1520
1521 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1522 #pragma omp atomic
1523 #endif
1524 progress++;
1525 proceed=SetImageProgress(image,YShearImageTag,progress,image->rows);
1526 if (proceed == MagickFalse)
1527 status=MagickFalse;
1528 }
1529 }
1530 image_view=DestroyCacheView(image_view);
1531 return(status);
1532 }
1533
1534 /*
1535 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1536 % %
1537 % %
1538 % %
1539 % S h e a r I m a g e %
1540 % %
1541 % %
1542 % %
1543 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1544 %
1545 % ShearImage() creates a new image that is a shear_image copy of an existing
1546 % one. Shearing slides one edge of an image along the X or Y axis, creating
1547 % a parallelogram. An X direction shear slides an edge along the X axis,
1548 % while a Y direction shear slides an edge along the Y axis. The amount of
1549 % the shear is controlled by a shear angle. For X direction shears, x_shear
1550 % is measured relative to the Y axis, and similarly, for Y direction shears
1551 % y_shear is measured relative to the X axis. Empty triangles left over from
1552 % shearing the image are filled with the background color defined by member
1553 % 'background_color' of the image.. ShearImage() allocates the memory
1554 % necessary for the new Image structure and returns a pointer to the new image.
1555 %
1556 % ShearImage() is based on the paper "A Fast Algorithm for General Raster
1557 % Rotatation" by Alan W. Paeth.
1558 %
1559 % The format of the ShearImage method is:
1560 %
1561 % Image *ShearImage(const Image *image,const double x_shear,
1562 % const double y_shear,ExceptionInfo *exception)
1563 %
1564 % A description of each parameter follows.
1565 %
1566 % o image: the image.
1567 %
1568 % o x_shear, y_shear: Specifies the number of degrees to shear the image.
1569 %
1570 % o exception: return any errors or warnings in this structure.
1571 %
1572 */
ShearImage(const Image * image,const double x_shear,const double y_shear,ExceptionInfo * exception)1573 MagickExport Image *ShearImage(const Image *image,const double x_shear,
1574 const double y_shear,ExceptionInfo *exception)
1575 {
1576 Image
1577 *integral_image,
1578 *shear_image;
1579
1580 MagickBooleanType
1581 status;
1582
1583 PointInfo
1584 shear;
1585
1586 RectangleInfo
1587 border_info,
1588 bounds;
1589
1590 assert(image != (Image *) NULL);
1591 assert(image->signature == MagickCoreSignature);
1592 if (image->debug != MagickFalse)
1593 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1594 assert(exception != (ExceptionInfo *) NULL);
1595 assert(exception->signature == MagickCoreSignature);
1596 if ((x_shear != 0.0) && (fmod(x_shear,90.0) == 0.0))
1597 ThrowImageException(ImageError,"AngleIsDiscontinuous");
1598 if ((y_shear != 0.0) && (fmod(y_shear,90.0) == 0.0))
1599 ThrowImageException(ImageError,"AngleIsDiscontinuous");
1600 /*
1601 Initialize shear angle.
1602 */
1603 integral_image=CloneImage(image,0,0,MagickTrue,exception);
1604 if (integral_image == (Image *) NULL)
1605 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1606 shear.x=(-tan(DegreesToRadians(fmod(x_shear,360.0))));
1607 shear.y=tan(DegreesToRadians(fmod(y_shear,360.0)));
1608 if ((shear.x == 0.0) && (shear.y == 0.0))
1609 return(integral_image);
1610 if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1611 {
1612 integral_image=DestroyImage(integral_image);
1613 return(integral_image);
1614 }
1615 if (integral_image->alpha_trait == UndefinedPixelTrait)
1616 (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1617 /*
1618 Compute image size.
1619 */
1620 bounds.width=image->columns+CastDoubleToLong(floor(fabs(shear.x)*
1621 image->rows+0.5));
1622 bounds.x=CastDoubleToLong(ceil((double) image->columns+((fabs(shear.x)*
1623 image->rows)-image->columns)/2.0-0.5));
1624 bounds.y=CastDoubleToLong(ceil((double) image->rows+((fabs(shear.y)*
1625 bounds.width)-image->rows)/2.0-0.5));
1626 /*
1627 Surround image with border.
1628 */
1629 integral_image->border_color=integral_image->background_color;
1630 integral_image->compose=CopyCompositeOp;
1631 border_info.width=(size_t) bounds.x;
1632 border_info.height=(size_t) bounds.y;
1633 shear_image=BorderImage(integral_image,&border_info,image->compose,exception);
1634 integral_image=DestroyImage(integral_image);
1635 if (shear_image == (Image *) NULL)
1636 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1637 /*
1638 Shear the image.
1639 */
1640 if (shear_image->alpha_trait == UndefinedPixelTrait)
1641 (void) SetImageAlphaChannel(shear_image,OpaqueAlphaChannel,exception);
1642 status=XShearImage(shear_image,shear.x,image->columns,image->rows,bounds.x,
1643 (ssize_t) (shear_image->rows-image->rows)/2,exception);
1644 if (status == MagickFalse)
1645 {
1646 shear_image=DestroyImage(shear_image);
1647 return((Image *) NULL);
1648 }
1649 status=YShearImage(shear_image,shear.y,bounds.width,image->rows,(ssize_t)
1650 (shear_image->columns-bounds.width)/2,bounds.y,exception);
1651 if (status == MagickFalse)
1652 {
1653 shear_image=DestroyImage(shear_image);
1654 return((Image *) NULL);
1655 }
1656 status=CropToFitImage(&shear_image,shear.x,shear.y,(MagickRealType)
1657 image->columns,(MagickRealType) image->rows,MagickFalse,exception);
1658 shear_image->alpha_trait=image->alpha_trait;
1659 shear_image->compose=image->compose;
1660 shear_image->page.width=0;
1661 shear_image->page.height=0;
1662 if (status == MagickFalse)
1663 shear_image=DestroyImage(shear_image);
1664 return(shear_image);
1665 }
1666
1667 /*
1668 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1669 % %
1670 % %
1671 % %
1672 % S h e a r R o t a t e I m a g e %
1673 % %
1674 % %
1675 % %
1676 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1677 %
1678 % ShearRotateImage() creates a new image that is a rotated copy of an existing
1679 % one. Positive angles rotate counter-clockwise (right-hand rule), while
1680 % negative angles rotate clockwise. Rotated images are usually larger than
1681 % the originals and have 'empty' triangular corners. X axis. Empty
1682 % triangles left over from shearing the image are filled with the background
1683 % color defined by member 'background_color' of the image. ShearRotateImage
1684 % allocates the memory necessary for the new Image structure and returns a
1685 % pointer to the new image.
1686 %
1687 % ShearRotateImage() is based on the paper "A Fast Algorithm for General
1688 % Raster Rotatation" by Alan W. Paeth. ShearRotateImage is adapted from a
1689 % similar method based on the Paeth paper written by Michael Halle of the
1690 % Spatial Imaging Group, MIT Media Lab.
1691 %
1692 % The format of the ShearRotateImage method is:
1693 %
1694 % Image *ShearRotateImage(const Image *image,const double degrees,
1695 % ExceptionInfo *exception)
1696 %
1697 % A description of each parameter follows.
1698 %
1699 % o image: the image.
1700 %
1701 % o degrees: Specifies the number of degrees to rotate the image.
1702 %
1703 % o exception: return any errors or warnings in this structure.
1704 %
1705 */
ShearRotateImage(const Image * image,const double degrees,ExceptionInfo * exception)1706 MagickExport Image *ShearRotateImage(const Image *image,const double degrees,
1707 ExceptionInfo *exception)
1708 {
1709 Image
1710 *integral_image,
1711 *rotate_image;
1712
1713 MagickBooleanType
1714 status;
1715
1716 MagickRealType
1717 angle;
1718
1719 PointInfo
1720 shear;
1721
1722 RectangleInfo
1723 border_info,
1724 bounds;
1725
1726 size_t
1727 height,
1728 rotations,
1729 shear_width,
1730 width;
1731
1732 /*
1733 Adjust rotation angle.
1734 */
1735 assert(image != (Image *) NULL);
1736 assert(image->signature == MagickCoreSignature);
1737 if (image->debug != MagickFalse)
1738 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1739 assert(exception != (ExceptionInfo *) NULL);
1740 assert(exception->signature == MagickCoreSignature);
1741 angle=fmod(degrees,360.0);
1742 if (angle < -45.0)
1743 angle+=360.0;
1744 for (rotations=0; angle > 45.0; rotations++)
1745 angle-=90.0;
1746 rotations%=4;
1747 /*
1748 Calculate shear equations.
1749 */
1750 integral_image=IntegralRotateImage(image,rotations,exception);
1751 if (integral_image == (Image *) NULL)
1752 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1753 shear.x=(-tan((double) DegreesToRadians(angle)/2.0));
1754 shear.y=sin((double) DegreesToRadians(angle));
1755 if ((shear.x == 0.0) && (shear.y == 0.0))
1756 return(integral_image);
1757 if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1758 {
1759 integral_image=DestroyImage(integral_image);
1760 return(integral_image);
1761 }
1762 if (integral_image->alpha_trait == UndefinedPixelTrait)
1763 (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1764 /*
1765 Compute maximum bounds for 3 shear operations.
1766 */
1767 width=integral_image->columns;
1768 height=integral_image->rows;
1769 bounds.width=(size_t) floor(fabs((double) height*shear.x)+width+0.5);
1770 bounds.height=(size_t) floor(fabs((double) bounds.width*shear.y)+height+0.5);
1771 shear_width=(size_t) floor(fabs((double) bounds.height*shear.x)+
1772 bounds.width+0.5);
1773 bounds.x=CastDoubleToLong(floor((double) ((shear_width > bounds.width) ?
1774 width : bounds.width-shear_width+2)/2.0+0.5));
1775 bounds.y=CastDoubleToLong(floor(((double) bounds.height-height+2)/2.0+0.5));
1776 /*
1777 Surround image with a border.
1778 */
1779 integral_image->border_color=integral_image->background_color;
1780 integral_image->compose=CopyCompositeOp;
1781 border_info.width=(size_t) bounds.x;
1782 border_info.height=(size_t) bounds.y;
1783 rotate_image=BorderImage(integral_image,&border_info,image->compose,
1784 exception);
1785 integral_image=DestroyImage(integral_image);
1786 if (rotate_image == (Image *) NULL)
1787 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1788 /*
1789 Rotate the image.
1790 */
1791 status=XShearImage(rotate_image,shear.x,width,height,bounds.x,(ssize_t)
1792 (rotate_image->rows-height)/2,exception);
1793 if (status == MagickFalse)
1794 {
1795 rotate_image=DestroyImage(rotate_image);
1796 return((Image *) NULL);
1797 }
1798 status=YShearImage(rotate_image,shear.y,bounds.width,height,(ssize_t)
1799 (rotate_image->columns-bounds.width)/2,bounds.y,exception);
1800 if (status == MagickFalse)
1801 {
1802 rotate_image=DestroyImage(rotate_image);
1803 return((Image *) NULL);
1804 }
1805 status=XShearImage(rotate_image,shear.x,bounds.width,bounds.height,(ssize_t)
1806 (rotate_image->columns-bounds.width)/2,(ssize_t) (rotate_image->rows-
1807 bounds.height)/2,exception);
1808 if (status == MagickFalse)
1809 {
1810 rotate_image=DestroyImage(rotate_image);
1811 return((Image *) NULL);
1812 }
1813 status=CropToFitImage(&rotate_image,shear.x,shear.y,(MagickRealType) width,
1814 (MagickRealType) height,MagickTrue,exception);
1815 rotate_image->alpha_trait=image->alpha_trait;
1816 rotate_image->compose=image->compose;
1817 rotate_image->page.width=0;
1818 rotate_image->page.height=0;
1819 if (status == MagickFalse)
1820 rotate_image=DestroyImage(rotate_image);
1821 return(rotate_image);
1822 }
1823