MagickCore  7.0.10
shear.c
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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 1999-2020 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"
52 #include "MagickCore/channel.h"
55 #include "MagickCore/composite.h"
57 #include "MagickCore/decorate.h"
58 #include "MagickCore/distort.h"
59 #include "MagickCore/draw.h"
60 #include "MagickCore/exception.h"
62 #include "MagickCore/gem.h"
63 #include "MagickCore/geometry.h"
64 #include "MagickCore/image.h"
66 #include "MagickCore/matrix.h"
67 #include "MagickCore/memory_.h"
68 #include "MagickCore/list.h"
69 #include "MagickCore/monitor.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"
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 */
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 
127  geometry,
128  page;
129 
130  register ssize_t
131  i;
132 
133  /*
134  Calculate the rotated image size.
135  */
136  extent[0].x=(double) (-width/2.0);
137  extent[0].y=(double) (-height/2.0);
138  extent[1].x=(double) width/2.0;
139  extent[1].y=(double) (-height/2.0);
140  extent[2].x=(double) (-width/2.0);
141  extent[2].y=(double) height/2.0;
142  extent[3].x=(double) width/2.0;
143  extent[3].y=(double) height/2.0;
144  for (i=0; i < 4; i++)
145  {
146  extent[i].x+=x_shear*extent[i].y;
147  extent[i].y+=y_shear*extent[i].x;
148  if (rotate != MagickFalse)
149  extent[i].x+=x_shear*extent[i].y;
150  extent[i].x+=(double) (*image)->columns/2.0;
151  extent[i].y+=(double) (*image)->rows/2.0;
152  }
153  min=extent[0];
154  max=extent[0];
155  for (i=1; i < 4; i++)
156  {
157  if (min.x > extent[i].x)
158  min.x=extent[i].x;
159  if (min.y > extent[i].y)
160  min.y=extent[i].y;
161  if (max.x < extent[i].x)
162  max.x=extent[i].x;
163  if (max.y < extent[i].y)
164  max.y=extent[i].y;
165  }
166  geometry.x=(ssize_t) ceil(min.x-0.5);
167  geometry.y=(ssize_t) ceil(min.y-0.5);
168  geometry.width=(size_t) floor(max.x-min.x+0.5);
169  geometry.height=(size_t) floor(max.y-min.y+0.5);
170  page=(*image)->page;
171  (void) ParseAbsoluteGeometry("0x0+0+0",&(*image)->page);
172  crop_image=CropImage(*image,&geometry,exception);
173  if (crop_image == (Image *) NULL)
174  return(MagickFalse);
175  crop_image->page=page;
176  *image=DestroyImage(*image);
177  *image=crop_image;
178  return(MagickTrue);
179 }
180 
181 /*
182 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
183 % %
184 % %
185 % %
186 % D e s k e w I m a g e %
187 % %
188 % %
189 % %
190 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
191 %
192 % DeskewImage() removes skew from the image. Skew is an artifact that
193 % occurs in scanned images because of the camera being misaligned,
194 % imperfections in the scanning or surface, or simply because the paper was
195 % not placed completely flat when scanned.
196 %
197 % The result will be auto-croped if the artifact "deskew:auto-crop" is
198 % defined, while the amount the image is to be deskewed, in degrees is also
199 % saved as the artifact "deskew:angle".
200 %
201 % The format of the DeskewImage method is:
202 %
203 % Image *DeskewImage(const Image *image,const double threshold,
204 % ExceptionInfo *exception)
205 %
206 % A description of each parameter follows:
207 %
208 % o image: the image.
209 %
210 % o threshold: separate background from foreground.
211 %
212 % o exception: return any errors or warnings in this structure.
213 %
214 */
215 
216 static void RadonProjection(const Image *image,MatrixInfo *source_matrixs,
217  MatrixInfo *destination_matrixs,const ssize_t sign,size_t *projection)
218 {
219  MatrixInfo
220  *swap;
221 
222  register MatrixInfo
223  *p,
224  *q;
225 
226  register ssize_t
227  x;
228 
229  size_t
230  step;
231 
232  p=source_matrixs;
233  q=destination_matrixs;
234  for (step=1; step < GetMatrixColumns(p); step*=2)
235  {
236  for (x=0; x < (ssize_t) GetMatrixColumns(p); x+=2*(ssize_t) step)
237  {
238  register ssize_t
239  i;
240 
241  ssize_t
242  y;
243 
244  unsigned short
245  element,
246  neighbor;
247 
248  for (i=0; i < (ssize_t) step; i++)
249  {
250  for (y=0; y < (ssize_t) (GetMatrixRows(p)-i-1); y++)
251  {
252  if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
253  continue;
254  if (GetMatrixElement(p,x+i+step,y+i,&neighbor) == MagickFalse)
255  continue;
256  neighbor+=element;
257  if (SetMatrixElement(q,x+2*i,y,&neighbor) == MagickFalse)
258  continue;
259  if (GetMatrixElement(p,x+i+step,y+i+1,&neighbor) == MagickFalse)
260  continue;
261  neighbor+=element;
262  if (SetMatrixElement(q,x+2*i+1,y,&neighbor) == MagickFalse)
263  continue;
264  }
265  for ( ; y < (ssize_t) (GetMatrixRows(p)-i); y++)
266  {
267  if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
268  continue;
269  if (GetMatrixElement(p,x+i+step,y+i,&neighbor) == MagickFalse)
270  continue;
271  neighbor+=element;
272  if (SetMatrixElement(q,x+2*i,y,&neighbor) == MagickFalse)
273  continue;
274  if (SetMatrixElement(q,x+2*i+1,y,&element) == MagickFalse)
275  continue;
276  }
277  for ( ; y < (ssize_t) GetMatrixRows(p); y++)
278  {
279  if (GetMatrixElement(p,x+i,y,&element) == MagickFalse)
280  continue;
281  if (SetMatrixElement(q,x+2*i,y,&element) == MagickFalse)
282  continue;
283  if (SetMatrixElement(q,x+2*i+1,y,&element) == MagickFalse)
284  continue;
285  }
286  }
287  }
288  swap=p;
289  p=q;
290  q=swap;
291  }
292 #if defined(MAGICKCORE_OPENMP_SUPPORT)
293  #pragma omp parallel for schedule(static) \
294  magick_number_threads(image,image,GetMatrixColumns(p),1)
295 #endif
296  for (x=0; x < (ssize_t) GetMatrixColumns(p); x++)
297  {
298  register ssize_t
299  y;
300 
301  size_t
302  sum;
303 
304  sum=0;
305  for (y=0; y < (ssize_t) (GetMatrixRows(p)-1); y++)
306  {
307  ssize_t
308  delta;
309 
310  unsigned short
311  element,
312  neighbor;
313 
314  if (GetMatrixElement(p,x,y,&element) == MagickFalse)
315  continue;
316  if (GetMatrixElement(p,x,y+1,&neighbor) == MagickFalse)
317  continue;
318  delta=(ssize_t) element-(ssize_t) neighbor;
319  sum+=delta*delta;
320  }
321  projection[GetMatrixColumns(p)+sign*x-1]=sum;
322  }
323 }
324 
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 
336  status;
337 
338  size_t
339  count,
340  width;
341 
342  ssize_t
343  j,
344  y;
345 
346  unsigned char
347  c;
348 
349  unsigned short
350  bits[256];
351 
352  for (width=1; width < ((image->columns+7)/8); width<<=1) ;
353  source_matrixs=AcquireMatrixInfo(width,image->rows,sizeof(unsigned short),
354  exception);
355  destination_matrixs=AcquireMatrixInfo(width,image->rows,
356  sizeof(unsigned short),exception);
357  if ((source_matrixs == (MatrixInfo *) NULL) ||
358  (destination_matrixs == (MatrixInfo *) NULL))
359  {
360  if (destination_matrixs != (MatrixInfo *) NULL)
361  destination_matrixs=DestroyMatrixInfo(destination_matrixs);
362  if (source_matrixs != (MatrixInfo *) NULL)
363  source_matrixs=DestroyMatrixInfo(source_matrixs);
364  return(MagickFalse);
365  }
366  if (NullMatrix(source_matrixs) == MagickFalse)
367  {
368  destination_matrixs=DestroyMatrixInfo(destination_matrixs);
369  source_matrixs=DestroyMatrixInfo(source_matrixs);
370  return(MagickFalse);
371  }
372  for (j=0; j < 256; j++)
373  {
374  c=(unsigned char) j;
375  for (count=0; c != 0; c>>=1)
376  count+=c & 0x01;
377  bits[j]=(unsigned short) count;
378  }
379  status=MagickTrue;
380  image_view=AcquireVirtualCacheView(image,exception);
381 #if defined(MAGICKCORE_OPENMP_SUPPORT)
382  #pragma omp parallel for schedule(static) shared(status) \
383  magick_number_threads(image,image,image->rows,1)
384 #endif
385  for (y=0; y < (ssize_t) image->rows; y++)
386  {
387  register const Quantum
388  *magick_restrict p;
389 
390  register ssize_t
391  i,
392  x;
393 
394  size_t
395  bit,
396  byte;
397 
398  unsigned short
399  value;
400 
401  if (status == MagickFalse)
402  continue;
403  p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
404  if (p == (const Quantum *) NULL)
405  {
406  status=MagickFalse;
407  continue;
408  }
409  bit=0;
410  byte=0;
411  i=(ssize_t) (image->columns+7)/8;
412  for (x=0; x < (ssize_t) image->columns; x++)
413  {
414  byte<<=1;
415  if (((MagickRealType) GetPixelRed(image,p) < threshold) ||
416  ((MagickRealType) GetPixelGreen(image,p) < threshold) ||
417  ((MagickRealType) GetPixelBlue(image,p) < threshold))
418  byte|=0x01;
419  bit++;
420  if (bit == 8)
421  {
422  value=bits[byte];
423  (void) SetMatrixElement(source_matrixs,--i,y,&value);
424  bit=0;
425  byte=0;
426  }
427  p+=GetPixelChannels(image);
428  }
429  if (bit != 0)
430  {
431  byte<<=(8-bit);
432  value=bits[byte];
433  (void) SetMatrixElement(source_matrixs,--i,y,&value);
434  }
435  }
436  RadonProjection(image,source_matrixs,destination_matrixs,-1,projection);
437  (void) NullMatrix(source_matrixs);
438 #if defined(MAGICKCORE_OPENMP_SUPPORT)
439  #pragma omp parallel for schedule(static) shared(status) \
440  magick_number_threads(image,image,image->rows,1)
441 #endif
442  for (y=0; y < (ssize_t) image->rows; y++)
443  {
444  register const Quantum
445  *magick_restrict p;
446 
447  register ssize_t
448  i,
449  x;
450 
451  size_t
452  bit,
453  byte;
454 
455  unsigned short
456  value;
457 
458  if (status == MagickFalse)
459  continue;
460  p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
461  if (p == (const Quantum *) NULL)
462  {
463  status=MagickFalse;
464  continue;
465  }
466  bit=0;
467  byte=0;
468  i=0;
469  for (x=0; x < (ssize_t) image->columns; x++)
470  {
471  byte<<=1;
472  if (((MagickRealType) GetPixelRed(image,p) < threshold) ||
473  ((MagickRealType) GetPixelGreen(image,p) < threshold) ||
474  ((MagickRealType) GetPixelBlue(image,p) < threshold))
475  byte|=0x01;
476  bit++;
477  if (bit == 8)
478  {
479  value=bits[byte];
480  (void) SetMatrixElement(source_matrixs,i++,y,&value);
481  bit=0;
482  byte=0;
483  }
484  p+=GetPixelChannels(image);
485  }
486  if (bit != 0)
487  {
488  byte<<=(8-bit);
489  value=bits[byte];
490  (void) SetMatrixElement(source_matrixs,i++,y,&value);
491  }
492  }
493  RadonProjection(image,source_matrixs,destination_matrixs,1,projection);
494  image_view=DestroyCacheView(image_view);
495  destination_matrixs=DestroyMatrixInfo(destination_matrixs);
496  source_matrixs=DestroyMatrixInfo(source_matrixs);
497  return(MagickTrue);
498 }
499 
500 static void GetImageBackgroundColor(Image *image,const ssize_t offset,
501  ExceptionInfo *exception)
502 {
503  CacheView
504  *image_view;
505 
506  PixelInfo
507  background;
508 
509  double
510  count;
511 
512  ssize_t
513  y;
514 
515  /*
516  Compute average background color.
517  */
518  if (offset <= 0)
519  return;
520  GetPixelInfo(image,&background);
521  count=0.0;
522  image_view=AcquireVirtualCacheView(image,exception);
523  for (y=0; y < (ssize_t) image->rows; y++)
524  {
525  register const Quantum
526  *magick_restrict p;
527 
528  register ssize_t
529  x;
530 
531  if ((y >= offset) && (y < ((ssize_t) image->rows-offset)))
532  continue;
533  p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
534  if (p == (const Quantum *) NULL)
535  continue;
536  for (x=0; x < (ssize_t) image->columns; x++)
537  {
538  if ((x >= offset) && (x < ((ssize_t) image->columns-offset)))
539  continue;
540  background.red+=QuantumScale*GetPixelRed(image,p);
541  background.green+=QuantumScale*GetPixelGreen(image,p);
542  background.blue+=QuantumScale*GetPixelBlue(image,p);
543  if ((GetPixelAlphaTraits(image) & UpdatePixelTrait) != 0)
544  background.alpha+=QuantumScale*GetPixelAlpha(image,p);
545  count++;
546  p+=GetPixelChannels(image);
547  }
548  }
549  image_view=DestroyCacheView(image_view);
551  background.red/count);
553  background.green/count);
555  background.blue/count);
556  if ((GetPixelAlphaTraits(image) & UpdatePixelTrait) != 0)
558  background.alpha/count);
559 }
560 
561 MagickExport Image *DeskewImage(const Image *image,const double threshold,
562  ExceptionInfo *exception)
563 {
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 
580  status;
581 
583  geometry;
584 
585  register ssize_t
586  i;
587 
588  size_t
589  max_projection,
590  *projection,
591  width;
592 
593  ssize_t
594  skew;
595 
596  /*
597  Compute deskew angle.
598  */
599  for (width=1; width < ((image->columns+7)/8); width<<=1) ;
600  projection=(size_t *) AcquireQuantumMemory((size_t) (2*width-1),
601  sizeof(*projection));
602  if (projection == (size_t *) NULL)
603  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
604  status=RadonTransform(image,threshold,projection,exception);
605  if (status == MagickFalse)
606  {
607  projection=(size_t *) RelinquishMagickMemory(projection);
608  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
609  }
610  max_projection=0;
611  skew=0;
612  for (i=0; i < (ssize_t) (2*width-1); i++)
613  {
614  if (projection[i] > max_projection)
615  {
616  skew=i-(ssize_t) width+1;
617  max_projection=projection[i];
618  }
619  }
620  projection=(size_t *) RelinquishMagickMemory(projection);
621  degrees=RadiansToDegrees(-atan((double) skew/width/8));
622  if (image->debug != MagickFalse)
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  }
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 */
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 
719  status;
720 
722  progress;
723 
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  register 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  {
797  sync;
798 
799  register const Quantum
800  *magick_restrict p;
801 
802  register Quantum
803  *magick_restrict q;
804 
805  register ssize_t
806  y;
807 
808  size_t
809  height,
810  width;
811 
812  width=tile_width;
813  if ((tile_x+(ssize_t) tile_width) > (ssize_t) image->columns)
814  width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
815  height=tile_height;
816  if ((tile_y+(ssize_t) tile_height) > (ssize_t) 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  register const Quantum
828  *magick_restrict tile_pixels;
829 
830  register 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  register 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  {
871  proceed;
872 
873  proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
874  image->rows);
875  if (proceed == MagickFalse)
876  status=MagickFalse;
877  }
878  }
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  register 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  {
902  sync;
903 
904  register const Quantum
905  *magick_restrict p;
906 
907  register Quantum
908  *magick_restrict q;
909 
910  register 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  register 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  {
949  proceed;
950 
951  proceed=SetImageProgress(image,RotateImageTag,progress++,
952  image->rows);
953  if (proceed == MagickFalse)
954  status=MagickFalse;
955  }
956  }
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  register 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  {
994  sync;
995 
996  register const Quantum
997  *magick_restrict p;
998 
999  register Quantum
1000  *magick_restrict q;
1001 
1002  register ssize_t
1003  y;
1004 
1005  size_t
1006  height,
1007  width;
1008 
1009  width=tile_width;
1010  if ((tile_x+(ssize_t) tile_width) > (ssize_t) image->columns)
1011  width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
1012  height=tile_height;
1013  if ((tile_y+(ssize_t) tile_height) > (ssize_t) 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  register const Quantum
1025  *magick_restrict tile_pixels;
1026 
1027  register 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  register 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  {
1070  proceed;
1071 
1072  proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
1073  image->rows);
1074  if (proceed == MagickFalse)
1075  status=MagickFalse;
1076  }
1077  }
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 */
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 
1150  status;
1151 
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  register Quantum
1188  *magick_restrict p,
1189  *magick_restrict q;
1190 
1191  register 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=(ssize_t) 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  {
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 */
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 
1367  status;
1368 
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  register Quantum
1405  *magick_restrict p,
1406  *magick_restrict q;
1407 
1408  register 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=(ssize_t) 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  {
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 */
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 
1581  status;
1582 
1583  PointInfo
1584  shear;
1585 
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+(ssize_t) floor(fabs(shear.x)*image->rows+0.5);
1621  bounds.x=(ssize_t) ceil((double) image->columns+((fabs(shear.x)*image->rows)-
1622  image->columns)/2.0-0.5);
1623  bounds.y=(ssize_t) ceil((double) image->rows+((fabs(shear.y)*bounds.width)-
1624  image->rows)/2.0-0.5);
1625  /*
1626  Surround image with border.
1627  */
1628  integral_image->border_color=integral_image->background_color;
1629  integral_image->compose=CopyCompositeOp;
1630  border_info.width=(size_t) bounds.x;
1631  border_info.height=(size_t) bounds.y;
1632  shear_image=BorderImage(integral_image,&border_info,image->compose,exception);
1633  integral_image=DestroyImage(integral_image);
1634  if (shear_image == (Image *) NULL)
1635  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1636  /*
1637  Shear the image.
1638  */
1639  if (shear_image->alpha_trait == UndefinedPixelTrait)
1640  (void) SetImageAlphaChannel(shear_image,OpaqueAlphaChannel,exception);
1641  status=XShearImage(shear_image,shear.x,image->columns,image->rows,bounds.x,
1642  (ssize_t) (shear_image->rows-image->rows)/2,exception);
1643  if (status == MagickFalse)
1644  {
1645  shear_image=DestroyImage(shear_image);
1646  return((Image *) NULL);
1647  }
1648  status=YShearImage(shear_image,shear.y,bounds.width,image->rows,(ssize_t)
1649  (shear_image->columns-bounds.width)/2,bounds.y,exception);
1650  if (status == MagickFalse)
1651  {
1652  shear_image=DestroyImage(shear_image);
1653  return((Image *) NULL);
1654  }
1655  status=CropToFitImage(&shear_image,shear.x,shear.y,(MagickRealType)
1656  image->columns,(MagickRealType) image->rows,MagickFalse,exception);
1657  shear_image->alpha_trait=image->alpha_trait;
1658  shear_image->compose=image->compose;
1659  shear_image->page.width=0;
1660  shear_image->page.height=0;
1661  if (status == MagickFalse)
1662  shear_image=DestroyImage(shear_image);
1663  return(shear_image);
1664 }
1665 
1666 /*
1667 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1668 % %
1669 % %
1670 % %
1671 % S h e a r R o t a t e I m a g e %
1672 % %
1673 % %
1674 % %
1675 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1676 %
1677 % ShearRotateImage() creates a new image that is a rotated copy of an existing
1678 % one. Positive angles rotate counter-clockwise (right-hand rule), while
1679 % negative angles rotate clockwise. Rotated images are usually larger than
1680 % the originals and have 'empty' triangular corners. X axis. Empty
1681 % triangles left over from shearing the image are filled with the background
1682 % color defined by member 'background_color' of the image. ShearRotateImage
1683 % allocates the memory necessary for the new Image structure and returns a
1684 % pointer to the new image.
1685 %
1686 % ShearRotateImage() is based on the paper "A Fast Algorithm for General
1687 % Raster Rotatation" by Alan W. Paeth. ShearRotateImage is adapted from a
1688 % similar method based on the Paeth paper written by Michael Halle of the
1689 % Spatial Imaging Group, MIT Media Lab.
1690 %
1691 % The format of the ShearRotateImage method is:
1692 %
1693 % Image *ShearRotateImage(const Image *image,const double degrees,
1694 % ExceptionInfo *exception)
1695 %
1696 % A description of each parameter follows.
1697 %
1698 % o image: the image.
1699 %
1700 % o degrees: Specifies the number of degrees to rotate the image.
1701 %
1702 % o exception: return any errors or warnings in this structure.
1703 %
1704 */
1705 MagickExport Image *ShearRotateImage(const Image *image,const double degrees,
1706  ExceptionInfo *exception)
1707 {
1708  Image
1709  *integral_image,
1710  *rotate_image;
1711 
1713  status;
1714 
1716  angle;
1717 
1718  PointInfo
1719  shear;
1720 
1722  border_info,
1723  bounds;
1724 
1725  size_t
1726  height,
1727  rotations,
1728  shear_width,
1729  width;
1730 
1731  /*
1732  Adjust rotation angle.
1733  */
1734  assert(image != (Image *) NULL);
1735  assert(image->signature == MagickCoreSignature);
1736  if (image->debug != MagickFalse)
1737  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1738  assert(exception != (ExceptionInfo *) NULL);
1739  assert(exception->signature == MagickCoreSignature);
1740  angle=fmod(degrees,360.0);
1741  if (angle < -45.0)
1742  angle+=360.0;
1743  for (rotations=0; angle > 45.0; rotations++)
1744  angle-=90.0;
1745  rotations%=4;
1746  /*
1747  Calculate shear equations.
1748  */
1749  integral_image=IntegralRotateImage(image,rotations,exception);
1750  if (integral_image == (Image *) NULL)
1751  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1752  shear.x=(-tan((double) DegreesToRadians(angle)/2.0));
1753  shear.y=sin((double) DegreesToRadians(angle));
1754  if ((shear.x == 0.0) && (shear.y == 0.0))
1755  return(integral_image);
1756  if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1757  {
1758  integral_image=DestroyImage(integral_image);
1759  return(integral_image);
1760  }
1761  if (integral_image->alpha_trait == UndefinedPixelTrait)
1762  (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1763  /*
1764  Compute maximum bounds for 3 shear operations.
1765  */
1766  width=integral_image->columns;
1767  height=integral_image->rows;
1768  bounds.width=(size_t) floor(fabs((double) height*shear.x)+width+0.5);
1769  bounds.height=(size_t) floor(fabs((double) bounds.width*shear.y)+height+0.5);
1770  shear_width=(size_t) floor(fabs((double) bounds.height*shear.x)+
1771  bounds.width+0.5);
1772  bounds.x=(ssize_t) floor((double) ((shear_width > bounds.width) ? width :
1773  bounds.width-shear_width+2)/2.0+0.5);
1774  bounds.y=(ssize_t) floor(((double) bounds.height-height+2)/2.0+0.5);
1775  /*
1776  Surround image with a border.
1777  */
1778  integral_image->border_color=integral_image->background_color;
1779  integral_image->compose=CopyCompositeOp;
1780  border_info.width=(size_t) bounds.x;
1781  border_info.height=(size_t) bounds.y;
1782  rotate_image=BorderImage(integral_image,&border_info,image->compose,
1783  exception);
1784  integral_image=DestroyImage(integral_image);
1785  if (rotate_image == (Image *) NULL)
1786  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1787  /*
1788  Rotate the image.
1789  */
1790  status=XShearImage(rotate_image,shear.x,width,height,bounds.x,(ssize_t)
1791  (rotate_image->rows-height)/2,exception);
1792  if (status == MagickFalse)
1793  {
1794  rotate_image=DestroyImage(rotate_image);
1795  return((Image *) NULL);
1796  }
1797  status=YShearImage(rotate_image,shear.y,bounds.width,height,(ssize_t)
1798  (rotate_image->columns-bounds.width)/2,bounds.y,exception);
1799  if (status == MagickFalse)
1800  {
1801  rotate_image=DestroyImage(rotate_image);
1802  return((Image *) NULL);
1803  }
1804  status=XShearImage(rotate_image,shear.x,bounds.width,bounds.height,(ssize_t)
1805  (rotate_image->columns-bounds.width)/2,(ssize_t) (rotate_image->rows-
1806  bounds.height)/2,exception);
1807  if (status == MagickFalse)
1808  {
1809  rotate_image=DestroyImage(rotate_image);
1810  return((Image *) NULL);
1811  }
1812  status=CropToFitImage(&rotate_image,shear.x,shear.y,(MagickRealType) width,
1813  (MagickRealType) height,MagickTrue,exception);
1814  rotate_image->alpha_trait=image->alpha_trait;
1815  rotate_image->compose=image->compose;
1816  rotate_image->page.width=0;
1817  rotate_image->page.height=0;
1818  if (status == MagickFalse)
1819  rotate_image=DestroyImage(rotate_image);
1820  return(rotate_image);
1821 }
size_t rows
Definition: image.h:172
#define magick_restrict
Definition: MagickCore.h:41
MagickDoubleType MagickRealType
Definition: magick-type.h:124
MagickExport CacheView * DestroyCacheView(CacheView *cache_view)
Definition: cache-view.c:252
double rx
Definition: geometry.h:95
MagickExport Image * DeskewImage(const Image *image, const double threshold, ExceptionInfo *exception)
Definition: shear.c:561
MagickProgressMonitor progress_monitor
Definition: image.h:303
static void GetImageBackgroundColor(Image *image, const ssize_t offset, ExceptionInfo *exception)
Definition: shear.c:500
ImageType type
Definition: image.h:264
MagickExport Image * ShearRotateImage(const Image *image, const double degrees, ExceptionInfo *exception)
Definition: shear.c:1705
static MagickBooleanType RadonTransform(const Image *image, const double threshold, size_t *projection, ExceptionInfo *exception)
Definition: shear.c:325
static Quantum GetPixelAlpha(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
static PixelTrait GetPixelAlphaTraits(const Image *magick_restrict image)
static Quantum GetPixelRed(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
PixelInfo border_color
Definition: image.h:179
MagickExport MagickBooleanType NullMatrix(MatrixInfo *matrix_info)
Definition: matrix.c:1003
double ty
Definition: geometry.h:95
size_t signature
Definition: exception.h:123
MagickExport MagickStatusType ParseAbsoluteGeometry(const char *geometry, RectangleInfo *region_info)
Definition: geometry.c:703
static void RadonProjection(const Image *image, MatrixInfo *source_matrixs, MatrixInfo *destination_matrixs, const ssize_t sign, size_t *projection)
Definition: shear.c:216
MagickPrivate void GetPixelCacheTileSize(const Image *, size_t *, size_t *)
MagickExport MagickBooleanType SetImageArtifact(Image *image, const char *artifact, const char *value)
Definition: artifact.c:445
MagickExport const char * GetImageArtifact(const Image *image, const char *artifact)
Definition: artifact.c:273
MagickRealType red
Definition: pixel.h:190
#define XShearImageTag
static PixelTrait GetPixelChannelTraits(const Image *magick_restrict image, const PixelChannel channel)
static MagickBooleanType 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)
Definition: shear.c:1134
MagickExport ssize_t FormatLocaleString(char *magick_restrict string, const size_t length, const char *magick_restrict format,...)
Definition: locale.c:499
static void SetPixelViaPixelInfo(const Image *magick_restrict image, const PixelInfo *magick_restrict pixel_info, Quantum *magick_restrict pixel)
MagickExport const Quantum * GetCacheViewVirtualPixels(const CacheView *cache_view, const ssize_t x, const ssize_t y, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: cache-view.c:651
static long StringToLong(const char *magick_restrict value)
MagickRealType alpha
Definition: pixel.h:190
MagickExport size_t GetMatrixColumns(const MatrixInfo *matrix_info)
Definition: matrix.c:609
MagickExport MagickBooleanType GetMatrixElement(const MatrixInfo *matrix_info, const ssize_t x, const ssize_t y, void *value)
Definition: matrix.c:705
size_t width
Definition: geometry.h:130
Definition: log.h:52
ssize_t MagickOffsetType
Definition: magick-type.h:133
static Quantum ClampToQuantum(const MagickRealType quantum)
Definition: quantum.h:85
MagickExport void GetPixelInfo(const Image *image, PixelInfo *pixel)
Definition: pixel.c:2170
Definition: image.h:151
double tx
Definition: geometry.h:95
MagickExport MagickBooleanType SetMatrixElement(const MatrixInfo *matrix_info, const ssize_t x, const ssize_t y, const void *value)
Definition: matrix.c:1110
MagickExport Image * AffineTransformImage(const Image *image, const AffineMatrix *affine_matrix, ExceptionInfo *exception)
Definition: distort.c:284
MagickExport Image * CropImage(const Image *image, const RectangleInfo *geometry, ExceptionInfo *exception)
Definition: transform.c:536
double x
Definition: geometry.h:123
#define MagickCoreSignature
MagickExport Quantum * GetCacheViewAuthenticPixels(CacheView *cache_view, const ssize_t x, const ssize_t y, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: cache-view.c:299
MagickExport MagickBooleanType SetImageAlphaChannel(Image *image, const AlphaChannelOption alpha_type, ExceptionInfo *exception)
Definition: channel.c:974
MagickBooleanType
Definition: magick-type.h:169
MagickExport Image * IntegralRotateImage(const Image *image, size_t rotations, ExceptionInfo *exception)
Definition: shear.c:706
#define YShearImageTag
MagickExport void * AcquireQuantumMemory(const size_t count, const size_t quantum)
Definition: memory.c:634
static double DegreesToRadians(const double degrees)
Definition: image-private.h:53
double y
Definition: geometry.h:123
RectangleInfo page
Definition: image.h:212
#define MagickPathExtent
double ry
Definition: geometry.h:95
static Quantum GetPixelGreen(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
MagickExport MagickBooleanType IsStringTrue(const char *value)
Definition: string.c:1425
static void CompositePixelInfoAreaBlend(const PixelInfo *p, const double alpha, const PixelInfo *q, const double beta, const double area, PixelInfo *composite)
static void GetPixelInfoPixel(const Image *magick_restrict image, const Quantum *magick_restrict pixel, PixelInfo *magick_restrict pixel_info)
PixelTrait alpha_trait
Definition: image.h:280
static MagickBooleanType 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)
Definition: shear.c:1351
MagickRealType blue
Definition: pixel.h:190
MagickExport Quantum * QueueCacheViewAuthenticPixels(CacheView *cache_view, const ssize_t x, const ssize_t y, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: cache-view.c:977
MagickExport VirtualPixelMethod SetImageVirtualPixelMethod(Image *image, const VirtualPixelMethod virtual_pixel_method, ExceptionInfo *exception)
Definition: image.c:3476
double sx
Definition: geometry.h:95
MagickExport MatrixInfo * AcquireMatrixInfo(const size_t columns, const size_t rows, const size_t stride, ExceptionInfo *exception)
Definition: matrix.c:200
MagickExport MagickBooleanType LogMagickEvent(const LogEventType type, const char *module, const char *function, const size_t line, const char *format,...)
Definition: log.c:1660
size_t signature
Definition: image.h:354
#define QuantumScale
Definition: magick-type.h:119
size_t columns
Definition: image.h:172
ssize_t x
Definition: geometry.h:134
size_t height
Definition: geometry.h:130
MagickExport MagickBooleanType SetImageStorageClass(Image *image, const ClassType storage_class, ExceptionInfo *exception)
Definition: image.c:2594
PixelChannel
Definition: pixel.h:67
static size_t GetPixelChannels(const Image *magick_restrict image)
char filename[MagickPathExtent]
Definition: image.h:319
#define GetMagickModule()
Definition: log.h:28
double sy
Definition: geometry.h:95
#define ThrowImageException(severity, tag)
static PixelChannel GetPixelChannelChannel(const Image *magick_restrict image, const ssize_t offset)
MagickExport CacheView * AcquireVirtualCacheView(const Image *image, ExceptionInfo *exception)
Definition: cache-view.c:149
MagickExport Image * ShearImage(const Image *image, const double x_shear, const double y_shear, ExceptionInfo *exception)
Definition: shear.c:1573
static double RadiansToDegrees(const double radians)
Definition: image-private.h:58
unsigned short Quantum
Definition: magick-type.h:86
MagickExport RectangleInfo GetImageBoundingBox(const Image *image, ExceptionInfo *exception)
Definition: attribute.c:386
MagickExport Image * BorderImage(const Image *image, const RectangleInfo *border_info, const CompositeOperator compose, ExceptionInfo *exception)
Definition: decorate.c:103
#define RotateImageTag
static void SetPixelChannel(const Image *magick_restrict image, const PixelChannel channel, const Quantum quantum, Quantum *magick_restrict pixel)
MagickExport void * RelinquishMagickMemory(void *memory)
Definition: memory.c:1123
MagickRealType green
Definition: pixel.h:190
MagickBooleanType(* MagickProgressMonitor)(const char *, const MagickOffsetType, const MagickSizeType, void *)
Definition: monitor.h:26
#define Swap(x, y)
Definition: studio.h:345
static MagickBooleanType CropToFitImage(Image **image, const double x_shear, const double y_shear, const double width, const double height, const MagickBooleanType rotate, ExceptionInfo *exception)
Definition: shear.c:113
CompositeOperator compose
Definition: image.h:234
#define MagickExport
MagickExport MagickBooleanType SyncCacheViewAuthenticPixels(CacheView *magick_restrict cache_view, ExceptionInfo *exception)
Definition: cache-view.c:1100
ssize_t y
Definition: geometry.h:134
MagickExport CacheView * AcquireAuthenticCacheView(const Image *image, ExceptionInfo *exception)
Definition: cache-view.c:112
static Quantum GetPixelBlue(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
PixelTrait
Definition: pixel.h:134
PixelInfo background_color
Definition: image.h:179
MagickExport Image * DestroyImage(Image *image)
Definition: image.c:1159
MagickExport Image * CloneImage(const Image *image, const size_t columns, const size_t rows, const MagickBooleanType detach, ExceptionInfo *exception)
Definition: image.c:774
MagickExport Image * StatisticImage(const Image *image, const StatisticType type, const size_t width, const size_t height, ExceptionInfo *exception)
Definition: statistic.c:2722
#define QuantumRange
Definition: magick-type.h:87
MagickExport MagickBooleanType SetImageProgress(const Image *image, const char *tag, const MagickOffsetType offset, const MagickSizeType extent)
Definition: monitor.c:136
MagickBooleanType debug
Definition: image.h:334
MagickExport size_t GetMatrixRows(const MatrixInfo *matrix_info)
Definition: matrix.c:751
MagickExport MatrixInfo * DestroyMatrixInfo(MatrixInfo *matrix_info)
Definition: matrix.c:369