MagickCore 7.1.2-26
Convert, Edit, Or Compose Bitmap Images
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shear.c
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 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/license/ %
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/profile-private.h"
74#include "MagickCore/quantum.h"
75#include "MagickCore/resource_.h"
76#include "MagickCore/shear.h"
77#include "MagickCore/statistic.h"
78#include "MagickCore/string_.h"
79#include "MagickCore/string-private.h"
80#include "MagickCore/thread-private.h"
81#include "MagickCore/threshold.h"
82#include "MagickCore/transform.h"
83␌
84/*
85%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
86% %
87% %
88% %
89% C r o p T o F i t I m a g e %
90% %
91% %
92% %
93%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
94%
95% CropToFitImage() crops the sheared image as determined by the bounding box
96% as defined by width and height and shearing angles.
97%
98% The format of the CropToFitImage method is:
99%
100% MagickBooleanType CropToFitImage(Image **image,
101% const double x_shear,const double x_shear,
102% const double width,const double height,
103% const MagickBooleanType rotate,ExceptionInfo *exception)
104%
105% A description of each parameter follows.
106%
107% o image: the image.
108%
109% o x_shear, y_shear, width, height: Defines a region of the image to crop.
110%
111% o exception: return any errors or warnings in this structure.
112%
113*/
114static MagickBooleanType CropToFitImage(Image **image,
115 const double x_shear,const double y_shear,
116 const double width,const double height,
117 const MagickBooleanType rotate,ExceptionInfo *exception)
118{
119 Image
120 *crop_image;
121
122 PointInfo
123 extent[4],
124 min,
125 max;
126
127 RectangleInfo
128 geometry,
129 page;
130
131 ssize_t
132 i;
133
134 /*
135 Calculate the rotated image size.
136 */
137 extent[0].x=(double) (-width/2.0);
138 extent[0].y=(double) (-height/2.0);
139 extent[1].x=(double) width/2.0;
140 extent[1].y=(double) (-height/2.0);
141 extent[2].x=(double) (-width/2.0);
142 extent[2].y=(double) height/2.0;
143 extent[3].x=(double) width/2.0;
144 extent[3].y=(double) height/2.0;
145 for (i=3; i >= 0; i--)
146 {
147 extent[i].x+=x_shear*extent[i].y;
148 extent[i].y+=y_shear*extent[i].x;
149 if (rotate != MagickFalse)
150 extent[i].x+=x_shear*extent[i].y;
151 extent[i].x+=(double) (*image)->columns/2.0;
152 extent[i].y+=(double) (*image)->rows/2.0;
153 }
154 min=extent[0];
155 max=extent[0];
156 for (i=1; i < 4; i++)
157 {
158 if (min.x > extent[i].x)
159 min.x=extent[i].x;
160 if (min.y > extent[i].y)
161 min.y=extent[i].y;
162 if (max.x < extent[i].x)
163 max.x=extent[i].x;
164 if (max.y < extent[i].y)
165 max.y=extent[i].y;
166 }
167 geometry.x=CastDoubleToSsizeT(ceil(min.x-0.5));
168 geometry.y=CastDoubleToSsizeT(ceil(min.y-0.5));
169 geometry.width=(size_t) CastDoubleToSsizeT(floor(max.x-min.x+0.5));
170 geometry.height=(size_t) CastDoubleToSsizeT(floor(max.y-min.y+0.5));
171 page=(*image)->page;
172 (void) ParseAbsoluteGeometry("0x0+0+0",&(*image)->page);
173 crop_image=CropImage(*image,&geometry,exception);
174 if (crop_image == (Image *) NULL)
175 return(MagickFalse);
176 crop_image->page=page;
177 *image=DestroyImage(*image);
178 *image=crop_image;
179 return(MagickTrue);
180}
181␌
182/*
183%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
184% %
185% %
186% %
187% D e s k e w I m a g e %
188% %
189% %
190% %
191%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
192%
193% DeskewImage() removes skew from the image. Skew is an artifact that
194% occurs in scanned images because of the camera being misaligned,
195% imperfections in the scanning or surface, or simply because the paper was
196% not placed completely flat when scanned.
197%
198% The result will be auto-cropped if the artifact "deskew:auto-crop" is
199% defined, while the amount the image is to be deskewed, in degrees is also
200% saved as the artifact "deskew:angle".
201%
202% The format of the DeskewImage method is:
203%
204% Image *DeskewImage(const Image *image,const double threshold,
205% ExceptionInfo *exception)
206%
207% A description of each parameter follows:
208%
209% o image: the image.
210%
211% o threshold: separate background from foreground.
212%
213% o exception: return any errors or warnings in this structure.
214%
215*/
216
217static void RadonProjection(MatrixInfo *source_matrices,
218 MatrixInfo *destination_matrices,const ssize_t sign,size_t *projection)
219{
220 MatrixInfo
221 *p,
222 *q,
223 *swap;
224
225 size_t
226 step;
227
228 ssize_t
229 x;
230
231 p=source_matrices;
232 q=destination_matrices;
233 for (step=1; step < GetMatrixColumns(p); step*=2)
234 {
235 for (x=0; x < (ssize_t) GetMatrixColumns(p); x+=2*(ssize_t) step)
236 {
237 ssize_t
238 i,
239 y;
240
241 unsigned short
242 element,
243 neighbor;
244
245 for (i=0; i < (ssize_t) step; i++)
246 {
247 for (y=0; y < ((ssize_t) GetMatrixRows(p)-i-1); y++)
248 {
249 if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
250 continue;
251 if (GetMatrixElement(p,x+i+(ssize_t) step,y+i,&neighbor) == MagickFalse)
252 continue;
253 neighbor+=element;
254 if (SetMatrixElement(q,x+2*i,y,&neighbor) == MagickFalse)
255 continue;
256 if (GetMatrixElement(p,x+i+(ssize_t) step,y+i+1,&neighbor) == MagickFalse)
257 continue;
258 neighbor+=element;
259 if (SetMatrixElement(q,x+2*i+1,y,&neighbor) == MagickFalse)
260 continue;
261 }
262 for ( ; y < ((ssize_t) GetMatrixRows(p)-i); y++)
263 {
264 if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
265 continue;
266 if (GetMatrixElement(p,x+i+(ssize_t) step,y+i,&neighbor) == MagickFalse)
267 continue;
268 neighbor+=element;
269 if (SetMatrixElement(q,x+2*i,y,&neighbor) == MagickFalse)
270 continue;
271 if (SetMatrixElement(q,x+2*i+1,y,&element) == MagickFalse)
272 continue;
273 }
274 for ( ; y < (ssize_t) GetMatrixRows(p); y++)
275 {
276 if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
277 continue;
278 if (SetMatrixElement(q,x+2*i,y,&element) == MagickFalse)
279 continue;
280 if (SetMatrixElement(q,x+2*i+1,y,&element) == MagickFalse)
281 continue;
282 }
283 }
284 }
285 swap=p;
286 p=q;
287 q=swap;
288 }
289#if defined(MAGICKCORE_OPENMP_SUPPORT)
290 #pragma omp parallel for schedule(static) \
291 num_threads((int) GetMagickResourceLimit(ThreadResource))
292#endif
293 for (x=0; x < (ssize_t) GetMatrixColumns(p); x++)
294 {
295 size_t
296 sum;
297
298 ssize_t
299 y;
300
301 sum=0;
302 for (y=0; y < (ssize_t) (GetMatrixRows(p)-1); y++)
303 {
304 ssize_t
305 delta;
306
307 unsigned short
308 element,
309 neighbor;
310
311 if (GetMatrixElement(p,x,y,&element) == MagickFalse)
312 continue;
313 if (GetMatrixElement(p,x,y+1,&neighbor) == MagickFalse)
314 continue;
315 delta=(ssize_t) element-(ssize_t) neighbor;
316 sum+=(size_t) (delta*delta);
317 }
318 projection[(ssize_t) GetMatrixColumns(p)+sign*x-1]=sum;
319 }
320}
321
322static MagickBooleanType RadonTransform(const Image *image,
323 const double threshold,size_t *projection,ExceptionInfo *exception)
324{
325 CacheView
326 *image_view;
327
328 MatrixInfo
329 *destination_matrices,
330 *source_matrices;
331
332 MagickBooleanType
333 status;
334
335 size_t
336 count,
337 width;
338
339 ssize_t
340 j,
341 y;
342
343 unsigned char
344 c;
345
346 unsigned short
347 bits[256];
348
349 for (width=1; width < ((image->columns+7)/8); width<<=1) ;
350 source_matrices=AcquireMatrixInfo(width,image->rows,sizeof(unsigned short),
351 exception);
352 destination_matrices=AcquireMatrixInfo(width,image->rows,
353 sizeof(unsigned short),exception);
354 if ((source_matrices == (MatrixInfo *) NULL) ||
355 (destination_matrices == (MatrixInfo *) NULL))
356 {
357 if (destination_matrices != (MatrixInfo *) NULL)
358 destination_matrices=DestroyMatrixInfo(destination_matrices);
359 if (source_matrices != (MatrixInfo *) NULL)
360 source_matrices=DestroyMatrixInfo(source_matrices);
361 return(MagickFalse);
362 }
363 if (NullMatrix(source_matrices) == MagickFalse)
364 {
365 destination_matrices=DestroyMatrixInfo(destination_matrices);
366 source_matrices=DestroyMatrixInfo(source_matrices);
367 return(MagickFalse);
368 }
369 for (j=0; j < 256; j++)
370 {
371 c=(unsigned char) j;
372 for (count=0; c != 0; c>>=1)
373 count+=c & 0x01;
374 bits[j]=(unsigned short) count;
375 }
376 status=MagickTrue;
377 image_view=AcquireVirtualCacheView(image,exception);
378#if defined(MAGICKCORE_OPENMP_SUPPORT)
379 #pragma omp parallel for schedule(static) shared(status) \
380 magick_number_threads(image,image,image->rows,2)
381#endif
382 for (y=0; y < (ssize_t) image->rows; y++)
383 {
384 const Quantum
385 *magick_restrict p;
386
387 size_t
388 bit,
389 byte;
390
391 ssize_t
392 i,
393 x;
394
395 unsigned short
396 value;
397
398 if (status == MagickFalse)
399 continue;
400 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
401 if (p == (const Quantum *) NULL)
402 {
403 status=MagickFalse;
404 continue;
405 }
406 bit=0;
407 byte=0;
408 i=(ssize_t) (image->columns+7)/8;
409 for (x=0; x < (ssize_t) image->columns; x++)
410 {
411 byte<<=1;
412 if (((MagickRealType) GetPixelRed(image,p) < threshold) ||
413 ((MagickRealType) GetPixelGreen(image,p) < threshold) ||
414 ((MagickRealType) GetPixelBlue(image,p) < threshold))
415 byte|=0x01;
416 bit++;
417 if (bit == 8)
418 {
419 value=bits[byte];
420 (void) SetMatrixElement(source_matrices,--i,y,&value);
421 bit=0;
422 byte=0;
423 }
424 p+=(ptrdiff_t) GetPixelChannels(image);
425 }
426 if (bit != 0)
427 {
428 byte<<=(8-bit);
429 value=bits[byte];
430 (void) SetMatrixElement(source_matrices,--i,y,&value);
431 }
432 }
433 RadonProjection(source_matrices,destination_matrices,-1,projection);
434 (void) NullMatrix(source_matrices);
435#if defined(MAGICKCORE_OPENMP_SUPPORT)
436 #pragma omp parallel for schedule(static) shared(status) \
437 magick_number_threads(image,image,image->rows,2)
438#endif
439 for (y=0; y < (ssize_t) image->rows; y++)
440 {
441 const Quantum
442 *magick_restrict p;
443
444 size_t
445 bit,
446 byte;
447
448 ssize_t
449 i,
450 x;
451
452 unsigned short
453 value;
454
455 if (status == MagickFalse)
456 continue;
457 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
458 if (p == (const Quantum *) NULL)
459 {
460 status=MagickFalse;
461 continue;
462 }
463 bit=0;
464 byte=0;
465 i=0;
466 for (x=0; x < (ssize_t) image->columns; x++)
467 {
468 byte<<=1;
469 if (((MagickRealType) GetPixelRed(image,p) < threshold) ||
470 ((MagickRealType) GetPixelGreen(image,p) < threshold) ||
471 ((MagickRealType) GetPixelBlue(image,p) < threshold))
472 byte|=0x01;
473 bit++;
474 if (bit == 8)
475 {
476 value=bits[byte];
477 (void) SetMatrixElement(source_matrices,i++,y,&value);
478 bit=0;
479 byte=0;
480 }
481 p+=(ptrdiff_t) GetPixelChannels(image);
482 }
483 if (bit != 0)
484 {
485 byte<<=(8-bit);
486 value=bits[byte];
487 (void) SetMatrixElement(source_matrices,i++,y,&value);
488 }
489 }
490 RadonProjection(source_matrices,destination_matrices,1,projection);
491 image_view=DestroyCacheView(image_view);
492 destination_matrices=DestroyMatrixInfo(destination_matrices);
493 source_matrices=DestroyMatrixInfo(source_matrices);
494 return(MagickTrue);
495}
496
497static void GetImageBackgroundColor(Image *image,const ssize_t offset,
498 ExceptionInfo *exception)
499{
500 CacheView
501 *image_view;
502
503 double
504 count;
505
506 PixelInfo
507 background;
508
509 ssize_t
510 y;
511
512 /*
513 Compute average background color.
514 */
515 if (offset <= 0)
516 return;
517 GetPixelInfo(image,&background);
518 count=0.0;
519 image_view=AcquireVirtualCacheView(image,exception);
520 for (y=0; y < (ssize_t) image->rows; y++)
521 {
522 const Quantum
523 *magick_restrict p;
524
525 ssize_t
526 x;
527
528 if ((y >= offset) && (y < ((ssize_t) image->rows-offset)))
529 continue;
530 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
531 if (p == (const Quantum *) NULL)
532 continue;
533 for (x=0; x < (ssize_t) image->columns; x++)
534 {
535 if ((x >= offset) && (x < ((ssize_t) image->columns-offset)))
536 continue;
537 background.red+=QuantumScale*(double) GetPixelRed(image,p);
538 background.green+=QuantumScale*(double) GetPixelGreen(image,p);
539 background.blue+=QuantumScale*(double) GetPixelBlue(image,p);
540 if ((GetPixelAlphaTraits(image) & UpdatePixelTrait) != 0)
541 background.alpha+=QuantumScale*(double) GetPixelAlpha(image,p);
542 count++;
543 p+=(ptrdiff_t) GetPixelChannels(image);
544 }
545 }
546 image_view=DestroyCacheView(image_view);
547 image->background_color.red=(double) ClampToQuantum((double) QuantumRange*
548 (double) background.red/count);
549 image->background_color.green=(double) ClampToQuantum((double) QuantumRange*
550 (double) background.green/count);
551 image->background_color.blue=(double) ClampToQuantum((double) QuantumRange*
552 (double) background.blue/count);
553 if ((GetPixelAlphaTraits(image) & UpdatePixelTrait) != 0)
554 image->background_color.alpha=(double) ClampToQuantum((double) QuantumRange*
555 (double) background.alpha/count);
556}
557
558MagickExport Image *DeskewImage(const Image *image,const double threshold,
559 ExceptionInfo *exception)
560{
561 AffineMatrix
562 affine_matrix;
563
564 const char
565 *artifact;
566
567 double
568 degrees;
569
570 Image
571 *clone_image,
572 *crop_image,
573 *deskew_image,
574 *median_image;
575
576 MagickBooleanType
577 status;
578
579 RectangleInfo
580 geometry;
581
582 size_t
583 max_projection,
584 *projection,
585 width;
586
587 ssize_t
588 i,
589 skew;
590
591 /*
592 Compute deskew angle.
593 */
594 for (width=1; width < ((image->columns+7)/8); width<<=1) ;
595 projection=(size_t *) AcquireQuantumMemory((size_t) (2*width-1),
596 sizeof(*projection));
597 if (projection == (size_t *) NULL)
598 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
599 status=RadonTransform(image,threshold,projection,exception);
600 if (status == MagickFalse)
601 {
602 projection=(size_t *) RelinquishMagickMemory(projection);
603 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
604 }
605 max_projection=0;
606 skew=0;
607 for (i=0; i < (ssize_t) (2*width-1); i++)
608 {
609 if (projection[i] > max_projection)
610 {
611 skew=i-(ssize_t) width+1;
612 max_projection=projection[i];
613 }
614 }
615 projection=(size_t *) RelinquishMagickMemory(projection);
616 degrees=RadiansToDegrees(-atan((double) skew/width/8));
617 if (image->debug != MagickFalse)
618 (void) LogMagickEvent(TransformEvent,GetMagickModule(),
619 " Deskew angle: %g",degrees);
620 /*
621 Deskew image.
622 */
623 clone_image=CloneImage(image,0,0,MagickTrue,exception);
624 if (clone_image == (Image *) NULL)
625 return((Image *) NULL);
626 {
627 char
628 angle[MagickPathExtent];
629
630 (void) FormatLocaleString(angle,MagickPathExtent,"%.20g",degrees);
631 (void) SetImageArtifact(clone_image,"deskew:angle",angle);
632 }
633 (void) SetImageVirtualPixelMethod(clone_image,BackgroundVirtualPixelMethod,
634 exception);
635 affine_matrix.sx=cos(DegreesToRadians(fmod((double) degrees,360.0)));
636 affine_matrix.rx=sin(DegreesToRadians(fmod((double) degrees,360.0)));
637 affine_matrix.ry=(-sin(DegreesToRadians(fmod((double) degrees,360.0))));
638 affine_matrix.sy=cos(DegreesToRadians(fmod((double) degrees,360.0)));
639 affine_matrix.tx=0.0;
640 affine_matrix.ty=0.0;
641 artifact=GetImageArtifact(image,"deskew:auto-crop");
642 if (IsStringTrue(artifact) == MagickFalse)
643 {
644 deskew_image=AffineTransformImage(clone_image,&affine_matrix,exception);
645 clone_image=DestroyImage(clone_image);
646 return(deskew_image);
647 }
648 /*
649 Auto-crop image.
650 */
651 GetImageBackgroundColor(clone_image,(ssize_t) StringToLong(artifact),
652 exception);
653 deskew_image=AffineTransformImage(clone_image,&affine_matrix,exception);
654 clone_image=DestroyImage(clone_image);
655 if (deskew_image == (Image *) NULL)
656 return((Image *) NULL);
657 median_image=StatisticImage(deskew_image,MedianStatistic,3,3,exception);
658 if (median_image == (Image *) NULL)
659 {
660 deskew_image=DestroyImage(deskew_image);
661 return((Image *) NULL);
662 }
663 geometry=GetImageBoundingBox(median_image,exception);
664 median_image=DestroyImage(median_image);
665 if (image->debug != MagickFalse)
666 (void) LogMagickEvent(TransformEvent,GetMagickModule()," Deskew geometry: "
667 "%.20gx%.20g%+.20g%+.20g",(double) geometry.width,(double)
668 geometry.height,(double) geometry.x,(double) geometry.y);
669 crop_image=CropImage(deskew_image,&geometry,exception);
670 deskew_image=DestroyImage(deskew_image);
671 return(crop_image);
672}
673␌
674/*
675%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
676% %
677% %
678% %
679% I n t e g r a l R o t a t e I m a g e %
680% %
681% %
682% %
683%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
684%
685% IntegralRotateImage() rotates the image an integral of 90 degrees. It
686% allocates the memory necessary for the new Image structure and returns a
687% pointer to the rotated image.
688%
689% The format of the IntegralRotateImage method is:
690%
691% Image *IntegralRotateImage(const Image *image,size_t rotations,
692% ExceptionInfo *exception)
693%
694% A description of each parameter follows.
695%
696% o image: the image.
697%
698% o rotations: Specifies the number of 90 degree rotations.
699%
700*/
701MagickExport Image *IntegralRotateImage(const Image *image,size_t rotations,
702 ExceptionInfo *exception)
703{
704#define RotateImageTag "Rotate/Image"
705
706 CacheView
707 *image_view,
708 *rotate_view;
709
710 Image
711 *rotate_image;
712
713 MagickBooleanType
714 status;
715
716 MagickOffsetType
717 progress;
718
719 RectangleInfo
720 page;
721
722 /*
723 Initialize rotated image attributes.
724 */
725 assert(image != (Image *) NULL);
726 page=image->page;
727 rotations%=4;
728 switch (rotations)
729 {
730 case 0:
731 default:
732 {
733 rotate_image=CloneImage(image,0,0,MagickTrue,exception);
734 break;
735 }
736 case 2:
737 {
738 rotate_image=CloneImage(image,image->columns,image->rows,MagickTrue,
739 exception);
740 break;
741 }
742 case 1:
743 case 3:
744 {
745 rotate_image=CloneImage(image,image->rows,image->columns,MagickTrue,
746 exception);
747 break;
748 }
749 }
750 if (rotate_image == (Image *) NULL)
751 return((Image *) NULL);
752 if (rotations == 0)
753 return(rotate_image);
754 /*
755 Integral rotate the image.
756 */
757 status=MagickTrue;
758 progress=0;
759 image_view=AcquireVirtualCacheView(image,exception);
760 rotate_view=AcquireAuthenticCacheView(rotate_image,exception);
761 switch (rotations)
762 {
763 case 1:
764 {
765 size_t
766 tile_height,
767 tile_width;
768
769 ssize_t
770 tile_y;
771
772 /*
773 Rotate 90 degrees.
774 */
775 GetPixelCacheTileSize(image,&tile_width,&tile_height);
776 tile_width=image->columns;
777#if defined(MAGICKCORE_OPENMP_SUPPORT)
778 #pragma omp parallel for schedule(static) shared(status) \
779 magick_number_threads(image,rotate_image,image->rows/tile_height,2)
780#endif
781 for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
782 {
783 ssize_t
784 tile_x;
785
786 if (status == MagickFalse)
787 continue;
788 tile_x=0;
789 for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
790 {
791 const Quantum
792 *magick_restrict p;
793
794 MagickBooleanType
795 sync;
796
797 Quantum
798 *magick_restrict q;
799
800 size_t
801 height,
802 width;
803
804 ssize_t
805 y;
806
807 width=tile_width;
808 if ((tile_width+(size_t) tile_x) > image->columns)
809 width=(size_t) ((ssize_t) tile_width-(tile_x+(ssize_t) tile_width-
810 (ssize_t) image->columns));
811 height=tile_height;
812 if ((tile_height+(size_t) tile_y) > image->rows)
813 height=(size_t) ((ssize_t) tile_height-(tile_y+(ssize_t)
814 tile_height-(ssize_t) image->rows));
815 p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
816 exception);
817 if (p == (const Quantum *) NULL)
818 {
819 status=MagickFalse;
820 break;
821 }
822 for (y=0; y < (ssize_t) width; y++)
823 {
824 const Quantum
825 *magick_restrict tile_pixels;
826
827 ssize_t
828 x;
829
830 if (status == MagickFalse)
831 continue;
832 q=QueueCacheViewAuthenticPixels(rotate_view,(ssize_t)
833 rotate_image->columns-(tile_y+(ssize_t) height),y+tile_x,height,
834 1,exception);
835 if (q == (Quantum *) NULL)
836 {
837 status=MagickFalse;
838 continue;
839 }
840 tile_pixels=p+(((ssize_t) height-1)*(ssize_t) width+y)*(ssize_t)
841 GetPixelChannels(image);
842 for (x=0; x < (ssize_t) height; x++)
843 {
844 ssize_t
845 i;
846
847 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
848 {
849 PixelChannel channel = GetPixelChannelChannel(image,i);
850 PixelTrait traits = GetPixelChannelTraits(image,channel);
851 PixelTrait rotate_traits = GetPixelChannelTraits(rotate_image,
852 channel);
853 if ((traits == UndefinedPixelTrait) ||
854 (rotate_traits == UndefinedPixelTrait))
855 continue;
856 SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
857 }
858 tile_pixels-=width*GetPixelChannels(image);
859 q+=(ptrdiff_t) GetPixelChannels(rotate_image);
860 }
861 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
862 if (sync == MagickFalse)
863 status=MagickFalse;
864 }
865 }
866 if (image->progress_monitor != (MagickProgressMonitor) NULL)
867 {
868 MagickBooleanType
869 proceed;
870
871 proceed=SetImageProgress(image,RotateImageTag,
872 progress+=(MagickOffsetType) tile_height,image->rows);
873 if (proceed == MagickFalse)
874 status=MagickFalse;
875 }
876 }
877 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
878 image->rows-1,image->rows);
879 Swap(page.width,page.height);
880 Swap(page.x,page.y);
881 if (page.width != 0)
882 page.x=(ssize_t) page.width-(ssize_t) rotate_image->columns-page.x;
883 break;
884 }
885 case 2:
886 {
887 ssize_t
888 y;
889
890 /*
891 Rotate 180 degrees.
892 */
893#if defined(MAGICKCORE_OPENMP_SUPPORT)
894 #pragma omp parallel for schedule(static) shared(status) \
895 magick_number_threads(image,rotate_image,image->rows,2)
896#endif
897 for (y=0; y < (ssize_t) image->rows; y++)
898 {
899 const Quantum
900 *magick_restrict p;
901
902 MagickBooleanType
903 sync;
904
905 Quantum
906 *magick_restrict q;
907
908 ssize_t
909 x;
910
911 if (status == MagickFalse)
912 continue;
913 p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
914 q=QueueCacheViewAuthenticPixels(rotate_view,0,(ssize_t) image->rows-y-1,
915 image->columns,1,exception);
916 if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
917 {
918 status=MagickFalse;
919 continue;
920 }
921 q+=(ptrdiff_t) GetPixelChannels(rotate_image)*image->columns;
922 for (x=0; x < (ssize_t) image->columns; x++)
923 {
924 ssize_t
925 i;
926
927 q-=GetPixelChannels(rotate_image);
928 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
929 {
930 PixelChannel channel = GetPixelChannelChannel(image,i);
931 PixelTrait traits = GetPixelChannelTraits(image,channel);
932 PixelTrait rotate_traits = GetPixelChannelTraits(rotate_image,
933 channel);
934 if ((traits == UndefinedPixelTrait) ||
935 (rotate_traits == UndefinedPixelTrait))
936 continue;
937 SetPixelChannel(rotate_image,channel,p[i],q);
938 }
939 p+=(ptrdiff_t) GetPixelChannels(image);
940 }
941 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
942 if (sync == MagickFalse)
943 status=MagickFalse;
944 if (image->progress_monitor != (MagickProgressMonitor) NULL)
945 {
946 MagickBooleanType
947 proceed;
948
949 proceed=SetImageProgress(image,RotateImageTag,progress++,
950 image->rows);
951 if (proceed == MagickFalse)
952 status=MagickFalse;
953 }
954 }
955 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
956 image->rows-1,image->rows);
957 if (page.width != 0)
958 page.x=(ssize_t) page.width-(ssize_t) rotate_image->columns-page.x;
959 if (page.height != 0)
960 page.y=(ssize_t) page.height-(ssize_t) rotate_image->rows-page.y;
961 break;
962 }
963 case 3:
964 {
965 size_t
966 tile_height,
967 tile_width;
968
969 ssize_t
970 tile_y;
971
972 /*
973 Rotate 270 degrees.
974 */
975 GetPixelCacheTileSize(image,&tile_width,&tile_height);
976 tile_width=image->columns;
977#if defined(MAGICKCORE_OPENMP_SUPPORT)
978 #pragma omp parallel for schedule(static) shared(status) \
979 magick_number_threads(image,rotate_image,image->rows/tile_height,2)
980#endif
981 for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
982 {
983 ssize_t
984 tile_x;
985
986 if (status == MagickFalse)
987 continue;
988 tile_x=0;
989 for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
990 {
991 MagickBooleanType
992 sync;
993
994 const Quantum
995 *magick_restrict p;
996
997 Quantum
998 *magick_restrict q;
999
1000 size_t
1001 height,
1002 width;
1003
1004 ssize_t
1005 y;
1006
1007 width=tile_width;
1008 if ((tile_width+(size_t) tile_x) > image->columns)
1009 width=(size_t) ((ssize_t) tile_width-(tile_x+(ssize_t) tile_width-
1010 (ssize_t) image->columns));
1011 height=tile_height;
1012 if ((tile_height+(size_t) tile_y) > image->rows)
1013 height=(size_t) ((ssize_t) tile_height-(tile_y+(ssize_t)
1014 tile_height-(ssize_t) 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,y+(ssize_t)
1033 rotate_image->rows-(tile_x+(ssize_t) width),height,1,exception);
1034 if (q == (Quantum *) NULL)
1035 {
1036 status=MagickFalse;
1037 continue;
1038 }
1039 tile_pixels=p+(((ssize_t) width-1)-y)*(ssize_t)
1040 GetPixelChannels(image);
1041 for (x=0; x < (ssize_t) height; x++)
1042 {
1043 ssize_t
1044 i;
1045
1046 for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1047 {
1048 PixelChannel channel = GetPixelChannelChannel(image,i);
1049 PixelTrait traits = GetPixelChannelTraits(image,channel);
1050 PixelTrait rotate_traits = GetPixelChannelTraits(rotate_image,
1051 channel);
1052 if ((traits == UndefinedPixelTrait) ||
1053 (rotate_traits == UndefinedPixelTrait))
1054 continue;
1055 SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
1056 }
1057 tile_pixels+=width*GetPixelChannels(image);
1058 q+=(ptrdiff_t) GetPixelChannels(rotate_image);
1059 }
1060#if defined(MAGICKCORE_OPENMP_SUPPORT)
1061 #pragma omp critical (MagickCore_IntegralRotateImage)
1062#endif
1063 sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
1064 if (sync == MagickFalse)
1065 status=MagickFalse;
1066 }
1067 }
1068 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1069 {
1070 MagickBooleanType
1071 proceed;
1072
1073 proceed=SetImageProgress(image,RotateImageTag,
1074 progress+=(MagickOffsetType) tile_height,image->rows);
1075 if (proceed == MagickFalse)
1076 status=MagickFalse;
1077 }
1078 }
1079 (void) SetImageProgress(image,RotateImageTag,(MagickOffsetType)
1080 image->rows-1,image->rows);
1081 Swap(page.width,page.height);
1082 Swap(page.x,page.y);
1083 if (page.height != 0)
1084 page.y=(ssize_t) page.height-(ssize_t) rotate_image->rows-page.y;
1085 break;
1086 }
1087 default:
1088 break;
1089 }
1090 rotate_view=DestroyCacheView(rotate_view);
1091 image_view=DestroyCacheView(image_view);
1092 rotate_image->type=image->type;
1093 rotate_image->page=page;
1094 if (status != MagickFalse)
1095 {
1096 char
1097 transform[MagickPathExtent];
1098
1099 (void) FormatLocaleString(transform,MagickPathExtent,
1100 "rotate %.20gx%.20g %.20g",(double) image->columns,
1101 (double) image->rows,(double) rotations);
1102 AppendImageProfileProperty(rotate_image,"hdrgm","hdrgm:Transform",
1103 transform,exception);
1104 }
1105 if (status == MagickFalse)
1106 rotate_image=DestroyImage(rotate_image);
1107 return(rotate_image);
1108}
1109␌
1110/*
1111%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1112% %
1113% %
1114% %
1115+ X S h e a r I m a g e %
1116% %
1117% %
1118% %
1119%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1120%
1121% XShearImage() shears the image in the X direction with a shear angle of
1122% 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1123% negative angles shear clockwise. Angles are measured relative to a vertical
1124% Y-axis. X shears will widen an image creating 'empty' triangles on the left
1125% and right sides of the source image.
1126%
1127% The format of the XShearImage method is:
1128%
1129% MagickBooleanType XShearImage(Image *image,const double degrees,
1130% const size_t width,const size_t height,
1131% const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1132%
1133% A description of each parameter follows.
1134%
1135% o image: the image.
1136%
1137% o degrees: A double representing the shearing angle along the X
1138% axis.
1139%
1140% o width, height, x_offset, y_offset: Defines a region of the image
1141% to shear.
1142%
1143% o exception: return any errors or warnings in this structure.
1144%
1145*/
1146static MagickBooleanType XShearImage(Image *image,const double degrees,
1147 const size_t width,const size_t height,const ssize_t x_offset,
1148 const ssize_t y_offset,ExceptionInfo *exception)
1149{
1150#define XShearImageTag "XShear/Image"
1151
1152 typedef enum
1153 {
1154 LEFT,
1155 RIGHT
1156 } ShearDirection;
1157
1158 CacheView
1159 *image_view;
1160
1161 MagickBooleanType
1162 status;
1163
1164 MagickOffsetType
1165 progress;
1166
1167 PixelInfo
1168 background;
1169
1170 ssize_t
1171 y;
1172
1173 /*
1174 X shear image.
1175 */
1176 assert(image != (Image *) NULL);
1177 assert(image->signature == MagickCoreSignature);
1178 if (IsEventLogging() != MagickFalse)
1179 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1180 status=MagickTrue;
1181 background=image->background_color;
1182 progress=0;
1183 image_view=AcquireAuthenticCacheView(image,exception);
1184#if defined(MAGICKCORE_OPENMP_SUPPORT)
1185 #pragma omp parallel for schedule(static) shared(progress,status) \
1186 magick_number_threads(image,image,height,1)
1187#endif
1188 for (y=0; y < (ssize_t) height; y++)
1189 {
1190 double
1191 area,
1192 displacement;
1193
1194 PixelInfo
1195 pixel,
1196 source,
1197 destination;
1198
1199 Quantum
1200 *magick_restrict p,
1201 *magick_restrict q;
1202
1203 ShearDirection
1204 direction;
1205
1206 ssize_t
1207 i,
1208 step;
1209
1210 if (status == MagickFalse)
1211 continue;
1212 p=GetCacheViewAuthenticPixels(image_view,0,y_offset+y,image->columns,1,
1213 exception);
1214 if (p == (Quantum *) NULL)
1215 {
1216 status=MagickFalse;
1217 continue;
1218 }
1219 p+=(ptrdiff_t) x_offset*(ssize_t) GetPixelChannels(image);
1220 displacement=degrees*(double) (y-height/2.0);
1221 if (displacement == 0.0)
1222 continue;
1223 if (displacement > 0.0)
1224 direction=RIGHT;
1225 else
1226 {
1227 displacement*=(-1.0);
1228 direction=LEFT;
1229 }
1230 step=CastDoubleToSsizeT(floor((double) displacement));
1231 area=(double) (displacement-step);
1232 step++;
1233 pixel=background;
1234 GetPixelInfo(image,&source);
1235 GetPixelInfo(image,&destination);
1236 switch (direction)
1237 {
1238 case LEFT:
1239 {
1240 /*
1241 Transfer pixels left-to-right.
1242 */
1243 if (step > x_offset)
1244 break;
1245 q=p-step*(ssize_t) GetPixelChannels(image);
1246 for (i=0; i < (ssize_t) width; i++)
1247 {
1248 if ((x_offset+i) < step)
1249 {
1250 p+=(ptrdiff_t) GetPixelChannels(image);
1251 GetPixelInfoPixel(image,p,&pixel);
1252 q+=(ptrdiff_t) GetPixelChannels(image);
1253 continue;
1254 }
1255 GetPixelInfoPixel(image,p,&source);
1256 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1257 &source,(double) GetPixelAlpha(image,p),area,&destination);
1258 SetPixelViaPixelInfo(image,&destination,q);
1259 GetPixelInfoPixel(image,p,&pixel);
1260 p+=(ptrdiff_t) GetPixelChannels(image);
1261 q+=(ptrdiff_t) GetPixelChannels(image);
1262 }
1263 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1264 &background,(double) background.alpha,area,&destination);
1265 SetPixelViaPixelInfo(image,&destination,q);
1266 q+=(ptrdiff_t) GetPixelChannels(image);
1267 for (i=0; i < (step-1); i++)
1268 {
1269 SetPixelViaPixelInfo(image,&background,q);
1270 q+=(ptrdiff_t) GetPixelChannels(image);
1271 }
1272 break;
1273 }
1274 case RIGHT:
1275 {
1276 /*
1277 Transfer pixels right-to-left.
1278 */
1279 p+=(ptrdiff_t) width*GetPixelChannels(image);
1280 q=p+step*(ssize_t) GetPixelChannels(image);
1281 for (i=0; i < (ssize_t) width; i++)
1282 {
1283 p-=(ptrdiff_t)GetPixelChannels(image);
1284 q-=GetPixelChannels(image);
1285 if ((size_t) (x_offset+(ssize_t) width+step-i) > image->columns)
1286 continue;
1287 GetPixelInfoPixel(image,p,&source);
1288 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1289 &source,(double) GetPixelAlpha(image,p),area,&destination);
1290 SetPixelViaPixelInfo(image,&destination,q);
1291 GetPixelInfoPixel(image,p,&pixel);
1292 }
1293 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1294 &background,(double) background.alpha,area,&destination);
1295 q-=GetPixelChannels(image);
1296 SetPixelViaPixelInfo(image,&destination,q);
1297 for (i=0; i < (step-1); i++)
1298 {
1299 q-=GetPixelChannels(image);
1300 SetPixelViaPixelInfo(image,&background,q);
1301 }
1302 break;
1303 }
1304 }
1305 if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1306 status=MagickFalse;
1307 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1308 {
1309 MagickBooleanType
1310 proceed;
1311
1312#if defined(MAGICKCORE_OPENMP_SUPPORT)
1313 #pragma omp atomic
1314#endif
1315 progress++;
1316 proceed=SetImageProgress(image,XShearImageTag,progress,height);
1317 if (proceed == MagickFalse)
1318 status=MagickFalse;
1319 }
1320 }
1321 image_view=DestroyCacheView(image_view);
1322 return(status);
1323}
1324␌
1325/*
1326%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1327% %
1328% %
1329% %
1330+ Y S h e a r I m a g e %
1331% %
1332% %
1333% %
1334%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1335%
1336% YShearImage shears the image in the Y direction with a shear angle of
1337% 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1338% negative angles shear clockwise. Angles are measured relative to a
1339% horizontal X-axis. Y shears will increase the height of an image creating
1340% 'empty' triangles on the top and bottom of the source image.
1341%
1342% The format of the YShearImage method is:
1343%
1344% MagickBooleanType YShearImage(Image *image,const double degrees,
1345% const size_t width,const size_t height,
1346% const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1347%
1348% A description of each parameter follows.
1349%
1350% o image: the image.
1351%
1352% o degrees: A double representing the shearing angle along the Y
1353% axis.
1354%
1355% o width, height, x_offset, y_offset: Defines a region of the image
1356% to shear.
1357%
1358% o exception: return any errors or warnings in this structure.
1359%
1360*/
1361static MagickBooleanType YShearImage(Image *image,const double degrees,
1362 const size_t width,const size_t height,const ssize_t x_offset,
1363 const ssize_t y_offset,ExceptionInfo *exception)
1364{
1365#define YShearImageTag "YShear/Image"
1366
1367 typedef enum
1368 {
1369 UP,
1370 DOWN
1371 } ShearDirection;
1372
1373 CacheView
1374 *image_view;
1375
1376 MagickBooleanType
1377 status;
1378
1379 MagickOffsetType
1380 progress;
1381
1382 PixelInfo
1383 background;
1384
1385 ssize_t
1386 x;
1387
1388 /*
1389 Y Shear image.
1390 */
1391 assert(image != (Image *) NULL);
1392 assert(image->signature == MagickCoreSignature);
1393 if (IsEventLogging() != MagickFalse)
1394 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1395 status=MagickTrue;
1396 progress=0;
1397 background=image->background_color;
1398 image_view=AcquireAuthenticCacheView(image,exception);
1399#if defined(MAGICKCORE_OPENMP_SUPPORT)
1400 #pragma omp parallel for schedule(static) shared(progress,status) \
1401 magick_number_threads(image,image,width,1)
1402#endif
1403 for (x=0; x < (ssize_t) width; x++)
1404 {
1405 double
1406 area,
1407 displacement;
1408
1409 PixelInfo
1410 pixel,
1411 source,
1412 destination;
1413
1414 Quantum
1415 *magick_restrict p,
1416 *magick_restrict q;
1417
1418 ShearDirection
1419 direction;
1420
1421 ssize_t
1422 i,
1423 step;
1424
1425 if (status == MagickFalse)
1426 continue;
1427 p=GetCacheViewAuthenticPixels(image_view,x_offset+x,0,1,image->rows,
1428 exception);
1429 if (p == (Quantum *) NULL)
1430 {
1431 status=MagickFalse;
1432 continue;
1433 }
1434 p+=(ptrdiff_t) y_offset*(ssize_t) GetPixelChannels(image);
1435 displacement=degrees*(double) (x-width/2.0);
1436 if (displacement == 0.0)
1437 continue;
1438 if (displacement > 0.0)
1439 direction=DOWN;
1440 else
1441 {
1442 displacement*=(-1.0);
1443 direction=UP;
1444 }
1445 step=CastDoubleToSsizeT(floor((double) displacement));
1446 area=(double) (displacement-step);
1447 step++;
1448 pixel=background;
1449 GetPixelInfo(image,&source);
1450 GetPixelInfo(image,&destination);
1451 switch (direction)
1452 {
1453 case UP:
1454 {
1455 /*
1456 Transfer pixels top-to-bottom.
1457 */
1458 if (step > y_offset)
1459 break;
1460 q=p-step*(ssize_t) GetPixelChannels(image);
1461 for (i=0; i < (ssize_t) height; i++)
1462 {
1463 if ((y_offset+i) < step)
1464 {
1465 p+=(ptrdiff_t) GetPixelChannels(image);
1466 GetPixelInfoPixel(image,p,&pixel);
1467 q+=(ptrdiff_t) GetPixelChannels(image);
1468 continue;
1469 }
1470 GetPixelInfoPixel(image,p,&source);
1471 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1472 &source,(double) GetPixelAlpha(image,p),area,
1473 &destination);
1474 SetPixelViaPixelInfo(image,&destination,q);
1475 GetPixelInfoPixel(image,p,&pixel);
1476 p+=(ptrdiff_t) GetPixelChannels(image);
1477 q+=(ptrdiff_t) GetPixelChannels(image);
1478 }
1479 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1480 &background,(double) background.alpha,area,&destination);
1481 SetPixelViaPixelInfo(image,&destination,q);
1482 q+=(ptrdiff_t) GetPixelChannels(image);
1483 for (i=0; i < (step-1); i++)
1484 {
1485 SetPixelViaPixelInfo(image,&background,q);
1486 q+=(ptrdiff_t) GetPixelChannels(image);
1487 }
1488 break;
1489 }
1490 case DOWN:
1491 {
1492 /*
1493 Transfer pixels bottom-to-top.
1494 */
1495 p+=(ptrdiff_t) height*GetPixelChannels(image);
1496 q=p+step*(ssize_t) GetPixelChannels(image);
1497 for (i=0; i < (ssize_t) height; i++)
1498 {
1499 p-=(ptrdiff_t)GetPixelChannels(image);
1500 q-=GetPixelChannels(image);
1501 if ((size_t) (y_offset+(ssize_t) height+step-i) > image->rows)
1502 continue;
1503 GetPixelInfoPixel(image,p,&source);
1504 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1505 &source,(double) GetPixelAlpha(image,p),area,
1506 &destination);
1507 SetPixelViaPixelInfo(image,&destination,q);
1508 GetPixelInfoPixel(image,p,&pixel);
1509 }
1510 CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1511 &background,(double) background.alpha,area,&destination);
1512 q-=GetPixelChannels(image);
1513 SetPixelViaPixelInfo(image,&destination,q);
1514 for (i=0; i < (step-1); i++)
1515 {
1516 q-=GetPixelChannels(image);
1517 SetPixelViaPixelInfo(image,&background,q);
1518 }
1519 break;
1520 }
1521 }
1522 if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1523 status=MagickFalse;
1524 if (image->progress_monitor != (MagickProgressMonitor) NULL)
1525 {
1526 MagickBooleanType
1527 proceed;
1528
1529#if defined(MAGICKCORE_OPENMP_SUPPORT)
1530 #pragma omp atomic
1531#endif
1532 progress++;
1533 proceed=SetImageProgress(image,YShearImageTag,progress,image->rows);
1534 if (proceed == MagickFalse)
1535 status=MagickFalse;
1536 }
1537 }
1538 image_view=DestroyCacheView(image_view);
1539 return(status);
1540}
1541␌
1542/*
1543%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1544% %
1545% %
1546% %
1547% S h e a r I m a g e %
1548% %
1549% %
1550% %
1551%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1552%
1553% ShearImage() creates a new image that is a shear_image copy of an existing
1554% one. Shearing slides one edge of an image along the X or Y axis, creating
1555% a parallelogram. An X direction shear slides an edge along the X axis,
1556% while a Y direction shear slides an edge along the Y axis. The amount of
1557% the shear is controlled by a shear angle. For X direction shears, x_shear
1558% is measured relative to the Y axis, and similarly, for Y direction shears
1559% y_shear is measured relative to the X axis. Empty triangles left over from
1560% shearing the image are filled with the background color defined by member
1561% 'background_color' of the image.. ShearImage() allocates the memory
1562% necessary for the new Image structure and returns a pointer to the new image.
1563%
1564% ShearImage() is based on the paper "A Fast Algorithm for General Raster
1565% Rotation" by Alan W. Paeth.
1566%
1567% The format of the ShearImage method is:
1568%
1569% Image *ShearImage(const Image *image,const double x_shear,
1570% const double y_shear,ExceptionInfo *exception)
1571%
1572% A description of each parameter follows.
1573%
1574% o image: the image.
1575%
1576% o x_shear, y_shear: Specifies the number of degrees to shear the image.
1577%
1578% o exception: return any errors or warnings in this structure.
1579%
1580*/
1581MagickExport Image *ShearImage(const Image *image,const double x_shear,
1582 const double y_shear,ExceptionInfo *exception)
1583{
1584 Image
1585 *integral_image,
1586 *shear_image;
1587
1588 MagickBooleanType
1589 status;
1590
1591 PointInfo
1592 shear;
1593
1594 RectangleInfo
1595 border_info,
1596 bounds;
1597
1598 assert(image != (Image *) NULL);
1599 assert(image->signature == MagickCoreSignature);
1600 assert(exception != (ExceptionInfo *) NULL);
1601 assert(exception->signature == MagickCoreSignature);
1602 if (IsEventLogging() != MagickFalse)
1603 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1604 if ((x_shear != 0.0) && (fmod(x_shear,90.0) == 0.0))
1605 ThrowImageException(ImageError,"AngleIsDiscontinuous");
1606 if ((y_shear != 0.0) && (fmod(y_shear,90.0) == 0.0))
1607 ThrowImageException(ImageError,"AngleIsDiscontinuous");
1608 /*
1609 Initialize shear angle.
1610 */
1611 integral_image=CloneImage(image,0,0,MagickTrue,exception);
1612 if (integral_image == (Image *) NULL)
1613 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1614 shear.x=(-tan(DegreesToRadians(fmod(x_shear,360.0))));
1615 shear.y=tan(DegreesToRadians(fmod(y_shear,360.0)));
1616 if ((shear.x == 0.0) && (shear.y == 0.0))
1617 return(integral_image);
1618 if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1619 {
1620 integral_image=DestroyImage(integral_image);
1621 return(integral_image);
1622 }
1623 if (integral_image->alpha_trait == UndefinedPixelTrait)
1624 (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1625 /*
1626 Compute image size.
1627 */
1628 bounds.width=(size_t) ((ssize_t) image->columns+CastDoubleToSsizeT(floor(
1629 fabs(shear.x)*image->rows+0.5)));
1630 bounds.x=CastDoubleToSsizeT(ceil((double) image->columns+((fabs(shear.x)*
1631 image->rows)-image->columns)/2.0-0.5));
1632 bounds.y=CastDoubleToSsizeT(ceil((double) image->rows+((fabs(shear.y)*
1633 bounds.width)-image->rows)/2.0-0.5));
1634 /*
1635 Surround image with border.
1636 */
1637 integral_image->border_color=integral_image->background_color;
1638 integral_image->compose=CopyCompositeOp;
1639 border_info.width=(size_t) bounds.x;
1640 border_info.height=(size_t) bounds.y;
1641 shear_image=BorderImage(integral_image,&border_info,image->compose,exception);
1642 integral_image=DestroyImage(integral_image);
1643 if (shear_image == (Image *) NULL)
1644 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1645 /*
1646 Shear the image.
1647 */
1648 if (shear_image->alpha_trait == UndefinedPixelTrait)
1649 (void) SetImageAlphaChannel(shear_image,OpaqueAlphaChannel,exception);
1650 status=XShearImage(shear_image,shear.x,image->columns,image->rows,bounds.x,
1651 (ssize_t) (shear_image->rows-image->rows)/2,exception);
1652 if (status == MagickFalse)
1653 {
1654 shear_image=DestroyImage(shear_image);
1655 return((Image *) NULL);
1656 }
1657 status=YShearImage(shear_image,shear.y,bounds.width,image->rows,(ssize_t)
1658 (shear_image->columns-bounds.width)/2,bounds.y,exception);
1659 if (status == MagickFalse)
1660 {
1661 shear_image=DestroyImage(shear_image);
1662 return((Image *) NULL);
1663 }
1664 status=CropToFitImage(&shear_image,shear.x,shear.y,(MagickRealType)
1665 image->columns,(MagickRealType) image->rows,MagickFalse,exception);
1666 shear_image->alpha_trait=image->alpha_trait;
1667 shear_image->compose=image->compose;
1668 shear_image->page.width=0;
1669 shear_image->page.height=0;
1670 if (status == MagickFalse)
1671 shear_image=DestroyImage(shear_image);
1672 return(shear_image);
1673}
1674␌
1675/*
1676%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1677% %
1678% %
1679% %
1680% S h e a r R o t a t e I m a g e %
1681% %
1682% %
1683% %
1684%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1685%
1686% ShearRotateImage() creates a new image that is a rotated copy of an existing
1687% one. Positive angles rotate counter-clockwise (right-hand rule), while
1688% negative angles rotate clockwise. Rotated images are usually larger than
1689% the originals and have 'empty' triangular corners. X axis. Empty
1690% triangles left over from shearing the image are filled with the background
1691% color defined by member 'background_color' of the image. ShearRotateImage
1692% allocates the memory necessary for the new Image structure and returns a
1693% pointer to the new image.
1694%
1695% ShearRotateImage() is based on the paper "A Fast Algorithm for General
1696% Raster Rotation" by Alan W. Paeth. ShearRotateImage is adapted from a
1697% similar method based on the Paeth paper written by Michael Halle of the
1698% Spatial Imaging Group, MIT Media Lab.
1699%
1700% The format of the ShearRotateImage method is:
1701%
1702% Image *ShearRotateImage(const Image *image,const double degrees,
1703% ExceptionInfo *exception)
1704%
1705% A description of each parameter follows.
1706%
1707% o image: the image.
1708%
1709% o degrees: Specifies the number of degrees to rotate the image.
1710%
1711% o exception: return any errors or warnings in this structure.
1712%
1713*/
1714MagickExport Image *ShearRotateImage(const Image *image,const double degrees,
1715 ExceptionInfo *exception)
1716{
1717 Image
1718 *integral_image,
1719 *rotate_image;
1720
1721 MagickBooleanType
1722 status;
1723
1724 MagickRealType
1725 angle;
1726
1727 PointInfo
1728 shear;
1729
1730 RectangleInfo
1731 border_info,
1732 bounds;
1733
1734 size_t
1735 height,
1736 rotations,
1737 shear_width,
1738 width;
1739
1740 /*
1741 Adjust rotation angle.
1742 */
1743 assert(image != (Image *) NULL);
1744 assert(image->signature == MagickCoreSignature);
1745 assert(exception != (ExceptionInfo *) NULL);
1746 assert(exception->signature == MagickCoreSignature);
1747 if (IsEventLogging() != MagickFalse)
1748 (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1749 angle=fmod(degrees,360.0);
1750 if (angle < -45.0)
1751 angle+=360.0;
1752 for (rotations=0; angle > 45.0; rotations++)
1753 angle-=90.0;
1754 rotations%=4;
1755 /*
1756 Calculate shear equations.
1757 */
1758 integral_image=IntegralRotateImage(image,rotations,exception);
1759 if (integral_image == (Image *) NULL)
1760 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1761 shear.x=(-tan((double) DegreesToRadians(angle)/2.0));
1762 shear.y=sin((double) DegreesToRadians(angle));
1763 if ((shear.x == 0.0) && (shear.y == 0.0))
1764 return(integral_image);
1765 if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1766 {
1767 integral_image=DestroyImage(integral_image);
1768 return(integral_image);
1769 }
1770 if (integral_image->alpha_trait == UndefinedPixelTrait)
1771 (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1772 /*
1773 Compute maximum bounds for 3 shear operations.
1774 */
1775 width=integral_image->columns;
1776 height=integral_image->rows;
1777 bounds.width=CastDoubleToSizeT(fabs((double) height*shear.x)+width+0.5);
1778 bounds.height=CastDoubleToSizeT(fabs((double) bounds.width*shear.y)+height+0.5);
1779 shear_width=CastDoubleToSizeT(fabs((double) bounds.height*shear.x)+
1780 bounds.width+0.5);
1781 bounds.x=CastDoubleToSsizeT(floor((double) ((shear_width > bounds.width) ?
1782 width : bounds.width-shear_width+2)/2.0+0.5));
1783 bounds.y=CastDoubleToSsizeT(floor(((double) bounds.height-height+2)/2.0+0.5));
1784 /*
1785 Surround image with a border.
1786 */
1787 integral_image->border_color=integral_image->background_color;
1788 integral_image->compose=CopyCompositeOp;
1789 border_info.width=(size_t) bounds.x;
1790 border_info.height=(size_t) bounds.y;
1791 rotate_image=BorderImage(integral_image,&border_info,image->compose,
1792 exception);
1793 integral_image=DestroyImage(integral_image);
1794 if (rotate_image == (Image *) NULL)
1795 ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1796 /*
1797 Rotate the image.
1798 */
1799 status=XShearImage(rotate_image,shear.x,width,height,bounds.x,(ssize_t)
1800 (rotate_image->rows-height)/2,exception);
1801 if (status == MagickFalse)
1802 {
1803 rotate_image=DestroyImage(rotate_image);
1804 return((Image *) NULL);
1805 }
1806 status=YShearImage(rotate_image,shear.y,bounds.width,height,(ssize_t)
1807 (rotate_image->columns-bounds.width)/2,bounds.y,exception);
1808 if (status == MagickFalse)
1809 {
1810 rotate_image=DestroyImage(rotate_image);
1811 return((Image *) NULL);
1812 }
1813 status=XShearImage(rotate_image,shear.x,bounds.width,bounds.height,(ssize_t)
1814 (rotate_image->columns-bounds.width)/2,(ssize_t) (rotate_image->rows-
1815 bounds.height)/2,exception);
1816 if (status == MagickFalse)
1817 {
1818 rotate_image=DestroyImage(rotate_image);
1819 return((Image *) NULL);
1820 }
1821 status=CropToFitImage(&rotate_image,shear.x,shear.y,(MagickRealType) width,
1822 (MagickRealType) height,MagickTrue,exception);
1823 rotate_image->alpha_trait=image->alpha_trait;
1824 rotate_image->compose=image->compose;
1825 rotate_image->page.width=0;
1826 rotate_image->page.height=0;
1827 if (status == MagickFalse)
1828 rotate_image=DestroyImage(rotate_image);
1829 return(rotate_image);
1830}