MagickCore  7.0.8
Convert, Edit, Or Compose Bitmap Images
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 1999-2018 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  if (rotations == 0)
734  return(CloneImage(image,0,0,MagickTrue,exception));
735  if ((rotations == 1) || (rotations == 3))
736  rotate_image=CloneImage(image,image->rows,image->columns,MagickTrue,
737  exception);
738  else
739  rotate_image=CloneImage(image,0,0,MagickTrue,
740  exception);
741  if (rotate_image == (Image *) NULL)
742  return((Image *) NULL);
743  /*
744  Integral rotate the image.
745  */
746  status=MagickTrue;
747  progress=0;
748  image_view=AcquireVirtualCacheView(image,exception);
749  rotate_view=AcquireAuthenticCacheView(rotate_image,exception);
750  switch (rotations)
751  {
752  case 1:
753  {
754  size_t
755  tile_height,
756  tile_width;
757 
758  ssize_t
759  tile_y;
760 
761  /*
762  Rotate 90 degrees.
763  */
764  GetPixelCacheTileSize(image,&tile_width,&tile_height);
765  tile_width=image->columns;
766 #if defined(MAGICKCORE_OPENMP_SUPPORT)
767  #pragma omp parallel for schedule(static) shared(status) \
768  magick_number_threads(image,image,image->rows/tile_height,1)
769 #endif
770  for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
771  {
772  register ssize_t
773  tile_x;
774 
775  if (status == MagickFalse)
776  continue;
777  tile_x=0;
778  for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
779  {
781  sync;
782 
783  register const Quantum
784  *magick_restrict p;
785 
786  register Quantum
787  *magick_restrict q;
788 
789  register ssize_t
790  y;
791 
792  size_t
793  height,
794  width;
795 
796  width=tile_width;
797  if ((tile_x+(ssize_t) tile_width) > (ssize_t) image->columns)
798  width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
799  height=tile_height;
800  if ((tile_y+(ssize_t) tile_height) > (ssize_t) image->rows)
801  height=(size_t) (tile_height-(tile_y+tile_height-image->rows));
802  p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
803  exception);
804  if (p == (const Quantum *) NULL)
805  {
806  status=MagickFalse;
807  break;
808  }
809  for (y=0; y < (ssize_t) width; y++)
810  {
811  register const Quantum
812  *magick_restrict tile_pixels;
813 
814  register ssize_t
815  x;
816 
817  if (status == MagickFalse)
818  continue;
819  q=QueueCacheViewAuthenticPixels(rotate_view,(ssize_t)
820  (rotate_image->columns-(tile_y+height)),y+tile_x,height,1,
821  exception);
822  if (q == (Quantum *) NULL)
823  {
824  status=MagickFalse;
825  continue;
826  }
827  tile_pixels=p+((height-1)*width+y)*GetPixelChannels(image);
828  for (x=0; x < (ssize_t) height; x++)
829  {
830  register ssize_t
831  i;
832 
833  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
834  {
835  PixelChannel channel = GetPixelChannelChannel(image,i);
836  PixelTrait traits = GetPixelChannelTraits(image,channel);
837  PixelTrait rotate_traits=GetPixelChannelTraits(rotate_image,
838  channel);
839  if ((traits == UndefinedPixelTrait) ||
840  (rotate_traits == UndefinedPixelTrait))
841  continue;
842  SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
843  }
844  tile_pixels-=width*GetPixelChannels(image);
845  q+=GetPixelChannels(rotate_image);
846  }
847  sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
848  if (sync == MagickFalse)
849  status=MagickFalse;
850  }
851  }
852  if (image->progress_monitor != (MagickProgressMonitor) NULL)
853  {
855  proceed;
856 
857 #if defined(MAGICKCORE_OPENMP_SUPPORT)
858  #pragma omp critical (MagickCore_IntegralRotateImage)
859 #endif
860  proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
861  image->rows);
862  if (proceed == MagickFalse)
863  status=MagickFalse;
864  }
865  }
867  image->rows-1,image->rows);
868  Swap(page.width,page.height);
869  Swap(page.x,page.y);
870  if (page.width != 0)
871  page.x=(ssize_t) (page.width-rotate_image->columns-page.x);
872  break;
873  }
874  case 2:
875  {
876  register ssize_t
877  y;
878 
879  /*
880  Rotate 180 degrees.
881  */
882 #if defined(MAGICKCORE_OPENMP_SUPPORT)
883  #pragma omp parallel for schedule(static) shared(status) \
884  magick_number_threads(image,image,image->rows,1)
885 #endif
886  for (y=0; y < (ssize_t) image->rows; y++)
887  {
889  sync;
890 
891  register const Quantum
892  *magick_restrict p;
893 
894  register Quantum
895  *magick_restrict q;
896 
897  register ssize_t
898  x;
899 
900  if (status == MagickFalse)
901  continue;
902  p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
903  q=QueueCacheViewAuthenticPixels(rotate_view,0,(ssize_t) (image->rows-y-
904  1),image->columns,1,exception);
905  if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
906  {
907  status=MagickFalse;
908  continue;
909  }
910  q+=GetPixelChannels(rotate_image)*image->columns;
911  for (x=0; x < (ssize_t) image->columns; x++)
912  {
913  register ssize_t
914  i;
915 
916  q-=GetPixelChannels(rotate_image);
917  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
918  {
919  PixelChannel channel = GetPixelChannelChannel(image,i);
920  PixelTrait traits = GetPixelChannelTraits(image,channel);
921  PixelTrait rotate_traits=GetPixelChannelTraits(rotate_image,
922  channel);
923  if ((traits == UndefinedPixelTrait) ||
924  (rotate_traits == UndefinedPixelTrait))
925  continue;
926  SetPixelChannel(rotate_image,channel,p[i],q);
927  }
928  p+=GetPixelChannels(image);
929  }
930  sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
931  if (sync == MagickFalse)
932  status=MagickFalse;
933  if (image->progress_monitor != (MagickProgressMonitor) NULL)
934  {
936  proceed;
937 
938 #if defined(MAGICKCORE_OPENMP_SUPPORT)
939  #pragma omp critical (MagickCore_IntegralRotateImage)
940 #endif
941  proceed=SetImageProgress(image,RotateImageTag,progress++,
942  image->rows);
943  if (proceed == MagickFalse)
944  status=MagickFalse;
945  }
946  }
948  image->rows-1,image->rows);
949  if (page.width != 0)
950  page.x=(ssize_t) (page.width-rotate_image->columns-page.x);
951  if (page.height != 0)
952  page.y=(ssize_t) (page.height-rotate_image->rows-page.y);
953  break;
954  }
955  case 3:
956  {
957  size_t
958  tile_height,
959  tile_width;
960 
961  ssize_t
962  tile_y;
963 
964  /*
965  Rotate 270 degrees.
966  */
967  GetPixelCacheTileSize(image,&tile_width,&tile_height);
968  tile_width=image->columns;
969 #if defined(MAGICKCORE_OPENMP_SUPPORT)
970  #pragma omp parallel for schedule(static) shared(status) \
971  magick_number_threads(image,image,image->rows/tile_height,1)
972 #endif
973  for (tile_y=0; tile_y < (ssize_t) image->rows; tile_y+=(ssize_t) tile_height)
974  {
975  register ssize_t
976  tile_x;
977 
978  if (status == MagickFalse)
979  continue;
980  tile_x=0;
981  for ( ; tile_x < (ssize_t) image->columns; tile_x+=(ssize_t) tile_width)
982  {
984  sync;
985 
986  register const Quantum
987  *magick_restrict p;
988 
989  register Quantum
990  *magick_restrict q;
991 
992  register ssize_t
993  y;
994 
995  size_t
996  height,
997  width;
998 
999  width=tile_width;
1000  if ((tile_x+(ssize_t) tile_width) > (ssize_t) image->columns)
1001  width=(size_t) (tile_width-(tile_x+tile_width-image->columns));
1002  height=tile_height;
1003  if ((tile_y+(ssize_t) tile_height) > (ssize_t) image->rows)
1004  height=(size_t) (tile_height-(tile_y+tile_height-image->rows));
1005  p=GetCacheViewVirtualPixels(image_view,tile_x,tile_y,width,height,
1006  exception);
1007  if (p == (const Quantum *) NULL)
1008  {
1009  status=MagickFalse;
1010  break;
1011  }
1012  for (y=0; y < (ssize_t) width; y++)
1013  {
1014  register const Quantum
1015  *magick_restrict tile_pixels;
1016 
1017  register ssize_t
1018  x;
1019 
1020  if (status == MagickFalse)
1021  continue;
1022  q=QueueCacheViewAuthenticPixels(rotate_view,tile_y,(ssize_t) (y+
1023  rotate_image->rows-(tile_x+width)),height,1,exception);
1024  if (q == (Quantum *) NULL)
1025  {
1026  status=MagickFalse;
1027  continue;
1028  }
1029  tile_pixels=p+((width-1)-y)*GetPixelChannels(image);
1030  for (x=0; x < (ssize_t) height; x++)
1031  {
1032  register ssize_t
1033  i;
1034 
1035  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1036  {
1037  PixelChannel channel = GetPixelChannelChannel(image,i);
1038  PixelTrait traits = GetPixelChannelTraits(image,channel);
1039  PixelTrait rotate_traits=GetPixelChannelTraits(rotate_image,
1040  channel);
1041  if ((traits == UndefinedPixelTrait) ||
1042  (rotate_traits == UndefinedPixelTrait))
1043  continue;
1044  SetPixelChannel(rotate_image,channel,tile_pixels[i],q);
1045  }
1046  tile_pixels+=width*GetPixelChannels(image);
1047  q+=GetPixelChannels(rotate_image);
1048  }
1049 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1050  #pragma omp critical (MagickCore_IntegralRotateImage)
1051 #endif
1052  sync=SyncCacheViewAuthenticPixels(rotate_view,exception);
1053  if (sync == MagickFalse)
1054  status=MagickFalse;
1055  }
1056  }
1057  if (image->progress_monitor != (MagickProgressMonitor) NULL)
1058  {
1060  proceed;
1061 
1062  proceed=SetImageProgress(image,RotateImageTag,progress+=tile_height,
1063  image->rows);
1064  if (proceed == MagickFalse)
1065  status=MagickFalse;
1066  }
1067  }
1069  image->rows-1,image->rows);
1070  Swap(page.width,page.height);
1071  Swap(page.x,page.y);
1072  if (page.height != 0)
1073  page.y=(ssize_t) (page.height-rotate_image->rows-page.y);
1074  break;
1075  }
1076  default:
1077  break;
1078  }
1079  rotate_view=DestroyCacheView(rotate_view);
1080  image_view=DestroyCacheView(image_view);
1081  rotate_image->type=image->type;
1082  rotate_image->page=page;
1083  if (status == MagickFalse)
1084  rotate_image=DestroyImage(rotate_image);
1085  return(rotate_image);
1086 }
1087 
1088 /*
1089 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1090 % %
1091 % %
1092 % %
1093 + X S h e a r I m a g e %
1094 % %
1095 % %
1096 % %
1097 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1098 %
1099 % XShearImage() shears the image in the X direction with a shear angle of
1100 % 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1101 % negative angles shear clockwise. Angles are measured relative to a vertical
1102 % Y-axis. X shears will widen an image creating 'empty' triangles on the left
1103 % and right sides of the source image.
1104 %
1105 % The format of the XShearImage method is:
1106 %
1107 % MagickBooleanType XShearImage(Image *image,const double degrees,
1108 % const size_t width,const size_t height,
1109 % const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1110 %
1111 % A description of each parameter follows.
1112 %
1113 % o image: the image.
1114 %
1115 % o degrees: A double representing the shearing angle along the X
1116 % axis.
1117 %
1118 % o width, height, x_offset, y_offset: Defines a region of the image
1119 % to shear.
1120 %
1121 % o exception: return any errors or warnings in this structure.
1122 %
1123 */
1124 static MagickBooleanType XShearImage(Image *image,const double degrees,
1125  const size_t width,const size_t height,const ssize_t x_offset,
1126  const ssize_t y_offset,ExceptionInfo *exception)
1127 {
1128 #define XShearImageTag "XShear/Image"
1129 
1130  typedef enum
1131  {
1132  LEFT,
1133  RIGHT
1134  } ShearDirection;
1135 
1136  CacheView
1137  *image_view;
1138 
1140  status;
1141 
1143  progress;
1144 
1145  PixelInfo
1146  background;
1147 
1148  ssize_t
1149  y;
1150 
1151  /*
1152  X shear image.
1153  */
1154  assert(image != (Image *) NULL);
1155  assert(image->signature == MagickCoreSignature);
1156  if (image->debug != MagickFalse)
1157  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1158  status=MagickTrue;
1159  background=image->background_color;
1160  progress=0;
1161  image_view=AcquireAuthenticCacheView(image,exception);
1162 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1163  #pragma omp parallel for schedule(static) shared(progress,status) \
1164  magick_number_threads(image,image,height,1)
1165 #endif
1166  for (y=0; y < (ssize_t) height; y++)
1167  {
1168  PixelInfo
1169  pixel,
1170  source,
1171  destination;
1172 
1173  double
1174  area,
1175  displacement;
1176 
1177  register Quantum
1178  *magick_restrict p,
1179  *magick_restrict q;
1180 
1181  register ssize_t
1182  i;
1183 
1184  ShearDirection
1185  direction;
1186 
1187  ssize_t
1188  step;
1189 
1190  if (status == MagickFalse)
1191  continue;
1192  p=GetCacheViewAuthenticPixels(image_view,0,y_offset+y,image->columns,1,
1193  exception);
1194  if (p == (Quantum *) NULL)
1195  {
1196  status=MagickFalse;
1197  continue;
1198  }
1199  p+=x_offset*GetPixelChannels(image);
1200  displacement=degrees*(double) (y-height/2.0);
1201  if (displacement == 0.0)
1202  continue;
1203  if (displacement > 0.0)
1204  direction=RIGHT;
1205  else
1206  {
1207  displacement*=(-1.0);
1208  direction=LEFT;
1209  }
1210  step=(ssize_t) floor((double) displacement);
1211  area=(double) (displacement-step);
1212  step++;
1213  pixel=background;
1214  GetPixelInfo(image,&source);
1215  GetPixelInfo(image,&destination);
1216  switch (direction)
1217  {
1218  case LEFT:
1219  {
1220  /*
1221  Transfer pixels left-to-right.
1222  */
1223  if (step > x_offset)
1224  break;
1225  q=p-step*GetPixelChannels(image);
1226  for (i=0; i < (ssize_t) width; i++)
1227  {
1228  if ((x_offset+i) < step)
1229  {
1230  p+=GetPixelChannels(image);
1231  GetPixelInfoPixel(image,p,&pixel);
1232  q+=GetPixelChannels(image);
1233  continue;
1234  }
1235  GetPixelInfoPixel(image,p,&source);
1236  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1237  &source,(double) GetPixelAlpha(image,p),area,&destination);
1238  SetPixelViaPixelInfo(image,&destination,q);
1239  GetPixelInfoPixel(image,p,&pixel);
1240  p+=GetPixelChannels(image);
1241  q+=GetPixelChannels(image);
1242  }
1243  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1244  &background,(double) background.alpha,area,&destination);
1245  SetPixelViaPixelInfo(image,&destination,q);
1246  q+=GetPixelChannels(image);
1247  for (i=0; i < (step-1); i++)
1248  {
1249  SetPixelViaPixelInfo(image,&background,q);
1250  q+=GetPixelChannels(image);
1251  }
1252  break;
1253  }
1254  case RIGHT:
1255  {
1256  /*
1257  Transfer pixels right-to-left.
1258  */
1259  p+=width*GetPixelChannels(image);
1260  q=p+step*GetPixelChannels(image);
1261  for (i=0; i < (ssize_t) width; i++)
1262  {
1263  p-=GetPixelChannels(image);
1264  q-=GetPixelChannels(image);
1265  if ((size_t) (x_offset+width+step-i) > image->columns)
1266  continue;
1267  GetPixelInfoPixel(image,p,&source);
1268  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1269  &source,(double) GetPixelAlpha(image,p),area,&destination);
1270  SetPixelViaPixelInfo(image,&destination,q);
1271  GetPixelInfoPixel(image,p,&pixel);
1272  }
1273  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1274  &background,(double) background.alpha,area,&destination);
1275  q-=GetPixelChannels(image);
1276  SetPixelViaPixelInfo(image,&destination,q);
1277  for (i=0; i < (step-1); i++)
1278  {
1279  q-=GetPixelChannels(image);
1280  SetPixelViaPixelInfo(image,&background,q);
1281  }
1282  break;
1283  }
1284  }
1285  if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1286  status=MagickFalse;
1287  if (image->progress_monitor != (MagickProgressMonitor) NULL)
1288  {
1290  proceed;
1291 
1292 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1293  #pragma omp critical (MagickCore_XShearImage)
1294 #endif
1295  proceed=SetImageProgress(image,XShearImageTag,progress++,height);
1296  if (proceed == MagickFalse)
1297  status=MagickFalse;
1298  }
1299  }
1300  image_view=DestroyCacheView(image_view);
1301  return(status);
1302 }
1303 
1304 /*
1305 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1306 % %
1307 % %
1308 % %
1309 + Y S h e a r I m a g e %
1310 % %
1311 % %
1312 % %
1313 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1314 %
1315 % YShearImage shears the image in the Y direction with a shear angle of
1316 % 'degrees'. Positive angles shear counter-clockwise (right-hand rule), and
1317 % negative angles shear clockwise. Angles are measured relative to a
1318 % horizontal X-axis. Y shears will increase the height of an image creating
1319 % 'empty' triangles on the top and bottom of the source image.
1320 %
1321 % The format of the YShearImage method is:
1322 %
1323 % MagickBooleanType YShearImage(Image *image,const double degrees,
1324 % const size_t width,const size_t height,
1325 % const ssize_t x_offset,const ssize_t y_offset,ExceptionInfo *exception)
1326 %
1327 % A description of each parameter follows.
1328 %
1329 % o image: the image.
1330 %
1331 % o degrees: A double representing the shearing angle along the Y
1332 % axis.
1333 %
1334 % o width, height, x_offset, y_offset: Defines a region of the image
1335 % to shear.
1336 %
1337 % o exception: return any errors or warnings in this structure.
1338 %
1339 */
1340 static MagickBooleanType YShearImage(Image *image,const double degrees,
1341  const size_t width,const size_t height,const ssize_t x_offset,
1342  const ssize_t y_offset,ExceptionInfo *exception)
1343 {
1344 #define YShearImageTag "YShear/Image"
1345 
1346  typedef enum
1347  {
1348  UP,
1349  DOWN
1350  } ShearDirection;
1351 
1352  CacheView
1353  *image_view;
1354 
1356  status;
1357 
1359  progress;
1360 
1361  PixelInfo
1362  background;
1363 
1364  ssize_t
1365  x;
1366 
1367  /*
1368  Y Shear image.
1369  */
1370  assert(image != (Image *) NULL);
1371  assert(image->signature == MagickCoreSignature);
1372  if (image->debug != MagickFalse)
1373  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1374  status=MagickTrue;
1375  progress=0;
1376  background=image->background_color;
1377  image_view=AcquireAuthenticCacheView(image,exception);
1378 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1379  #pragma omp parallel for schedule(static) shared(progress,status) \
1380  magick_number_threads(image,image,width,1)
1381 #endif
1382  for (x=0; x < (ssize_t) width; x++)
1383  {
1384  ssize_t
1385  step;
1386 
1387  double
1388  area,
1389  displacement;
1390 
1391  PixelInfo
1392  pixel,
1393  source,
1394  destination;
1395 
1396  register Quantum
1397  *magick_restrict p,
1398  *magick_restrict q;
1399 
1400  register ssize_t
1401  i;
1402 
1403  ShearDirection
1404  direction;
1405 
1406  if (status == MagickFalse)
1407  continue;
1408  p=GetCacheViewAuthenticPixels(image_view,x_offset+x,0,1,image->rows,
1409  exception);
1410  if (p == (Quantum *) NULL)
1411  {
1412  status=MagickFalse;
1413  continue;
1414  }
1415  p+=y_offset*GetPixelChannels(image);
1416  displacement=degrees*(double) (x-width/2.0);
1417  if (displacement == 0.0)
1418  continue;
1419  if (displacement > 0.0)
1420  direction=DOWN;
1421  else
1422  {
1423  displacement*=(-1.0);
1424  direction=UP;
1425  }
1426  step=(ssize_t) floor((double) displacement);
1427  area=(double) (displacement-step);
1428  step++;
1429  pixel=background;
1430  GetPixelInfo(image,&source);
1431  GetPixelInfo(image,&destination);
1432  switch (direction)
1433  {
1434  case UP:
1435  {
1436  /*
1437  Transfer pixels top-to-bottom.
1438  */
1439  if (step > y_offset)
1440  break;
1441  q=p-step*GetPixelChannels(image);
1442  for (i=0; i < (ssize_t) height; i++)
1443  {
1444  if ((y_offset+i) < step)
1445  {
1446  p+=GetPixelChannels(image);
1447  GetPixelInfoPixel(image,p,&pixel);
1448  q+=GetPixelChannels(image);
1449  continue;
1450  }
1451  GetPixelInfoPixel(image,p,&source);
1452  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1453  &source,(double) GetPixelAlpha(image,p),area,
1454  &destination);
1455  SetPixelViaPixelInfo(image,&destination,q);
1456  GetPixelInfoPixel(image,p,&pixel);
1457  p+=GetPixelChannels(image);
1458  q+=GetPixelChannels(image);
1459  }
1460  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1461  &background,(double) background.alpha,area,&destination);
1462  SetPixelViaPixelInfo(image,&destination,q);
1463  q+=GetPixelChannels(image);
1464  for (i=0; i < (step-1); i++)
1465  {
1466  SetPixelViaPixelInfo(image,&background,q);
1467  q+=GetPixelChannels(image);
1468  }
1469  break;
1470  }
1471  case DOWN:
1472  {
1473  /*
1474  Transfer pixels bottom-to-top.
1475  */
1476  p+=height*GetPixelChannels(image);
1477  q=p+step*GetPixelChannels(image);
1478  for (i=0; i < (ssize_t) height; i++)
1479  {
1480  p-=GetPixelChannels(image);
1481  q-=GetPixelChannels(image);
1482  if ((size_t) (y_offset+height+step-i) > image->rows)
1483  continue;
1484  GetPixelInfoPixel(image,p,&source);
1485  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1486  &source,(double) GetPixelAlpha(image,p),area,
1487  &destination);
1488  SetPixelViaPixelInfo(image,&destination,q);
1489  GetPixelInfoPixel(image,p,&pixel);
1490  }
1491  CompositePixelInfoAreaBlend(&pixel,(double) pixel.alpha,
1492  &background,(double) background.alpha,area,&destination);
1493  q-=GetPixelChannels(image);
1494  SetPixelViaPixelInfo(image,&destination,q);
1495  for (i=0; i < (step-1); i++)
1496  {
1497  q-=GetPixelChannels(image);
1498  SetPixelViaPixelInfo(image,&background,q);
1499  }
1500  break;
1501  }
1502  }
1503  if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1504  status=MagickFalse;
1505  if (image->progress_monitor != (MagickProgressMonitor) NULL)
1506  {
1508  proceed;
1509 
1510 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1511  #pragma omp critical (MagickCore_YShearImage)
1512 #endif
1513  proceed=SetImageProgress(image,YShearImageTag,progress++,image->rows);
1514  if (proceed == MagickFalse)
1515  status=MagickFalse;
1516  }
1517  }
1518  image_view=DestroyCacheView(image_view);
1519  return(status);
1520 }
1521 
1522 /*
1523 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1524 % %
1525 % %
1526 % %
1527 % S h e a r I m a g e %
1528 % %
1529 % %
1530 % %
1531 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1532 %
1533 % ShearImage() creates a new image that is a shear_image copy of an existing
1534 % one. Shearing slides one edge of an image along the X or Y axis, creating
1535 % a parallelogram. An X direction shear slides an edge along the X axis,
1536 % while a Y direction shear slides an edge along the Y axis. The amount of
1537 % the shear is controlled by a shear angle. For X direction shears, x_shear
1538 % is measured relative to the Y axis, and similarly, for Y direction shears
1539 % y_shear is measured relative to the X axis. Empty triangles left over from
1540 % shearing the image are filled with the background color defined by member
1541 % 'background_color' of the image.. ShearImage() allocates the memory
1542 % necessary for the new Image structure and returns a pointer to the new image.
1543 %
1544 % ShearImage() is based on the paper "A Fast Algorithm for General Raster
1545 % Rotatation" by Alan W. Paeth.
1546 %
1547 % The format of the ShearImage method is:
1548 %
1549 % Image *ShearImage(const Image *image,const double x_shear,
1550 % const double y_shear,ExceptionInfo *exception)
1551 %
1552 % A description of each parameter follows.
1553 %
1554 % o image: the image.
1555 %
1556 % o x_shear, y_shear: Specifies the number of degrees to shear the image.
1557 %
1558 % o exception: return any errors or warnings in this structure.
1559 %
1560 */
1561 MagickExport Image *ShearImage(const Image *image,const double x_shear,
1562  const double y_shear,ExceptionInfo *exception)
1563 {
1564  Image
1565  *integral_image,
1566  *shear_image;
1567 
1569  status;
1570 
1571  PointInfo
1572  shear;
1573 
1575  border_info,
1576  bounds;
1577 
1578  assert(image != (Image *) NULL);
1579  assert(image->signature == MagickCoreSignature);
1580  if (image->debug != MagickFalse)
1581  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1582  assert(exception != (ExceptionInfo *) NULL);
1583  assert(exception->signature == MagickCoreSignature);
1584  if ((x_shear != 0.0) && (fmod(x_shear,90.0) == 0.0))
1585  ThrowImageException(ImageError,"AngleIsDiscontinuous");
1586  if ((y_shear != 0.0) && (fmod(y_shear,90.0) == 0.0))
1587  ThrowImageException(ImageError,"AngleIsDiscontinuous");
1588  /*
1589  Initialize shear angle.
1590  */
1591  integral_image=CloneImage(image,0,0,MagickTrue,exception);
1592  if (integral_image == (Image *) NULL)
1593  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1594  shear.x=(-tan(DegreesToRadians(fmod(x_shear,360.0))));
1595  shear.y=tan(DegreesToRadians(fmod(y_shear,360.0)));
1596  if ((shear.x == 0.0) && (shear.y == 0.0))
1597  return(integral_image);
1598  if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1599  {
1600  integral_image=DestroyImage(integral_image);
1601  return(integral_image);
1602  }
1603  if (integral_image->alpha_trait == UndefinedPixelTrait)
1604  (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1605  /*
1606  Compute image size.
1607  */
1608  bounds.width=image->columns+(ssize_t) floor(fabs(shear.x)*image->rows+0.5);
1609  bounds.x=(ssize_t) ceil((double) image->columns+((fabs(shear.x)*image->rows)-
1610  image->columns)/2.0-0.5);
1611  bounds.y=(ssize_t) ceil((double) image->rows+((fabs(shear.y)*bounds.width)-
1612  image->rows)/2.0-0.5);
1613  /*
1614  Surround image with border.
1615  */
1616  integral_image->border_color=integral_image->background_color;
1617  integral_image->compose=CopyCompositeOp;
1618  border_info.width=(size_t) bounds.x;
1619  border_info.height=(size_t) bounds.y;
1620  shear_image=BorderImage(integral_image,&border_info,image->compose,exception);
1621  integral_image=DestroyImage(integral_image);
1622  if (shear_image == (Image *) NULL)
1623  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1624  /*
1625  Shear the image.
1626  */
1627  if (shear_image->alpha_trait == UndefinedPixelTrait)
1628  (void) SetImageAlphaChannel(shear_image,OpaqueAlphaChannel,exception);
1629  status=XShearImage(shear_image,shear.x,image->columns,image->rows,bounds.x,
1630  (ssize_t) (shear_image->rows-image->rows)/2,exception);
1631  if (status == MagickFalse)
1632  {
1633  shear_image=DestroyImage(shear_image);
1634  return((Image *) NULL);
1635  }
1636  status=YShearImage(shear_image,shear.y,bounds.width,image->rows,(ssize_t)
1637  (shear_image->columns-bounds.width)/2,bounds.y,exception);
1638  if (status == MagickFalse)
1639  {
1640  shear_image=DestroyImage(shear_image);
1641  return((Image *) NULL);
1642  }
1643  status=CropToFitImage(&shear_image,shear.x,shear.y,(MagickRealType)
1644  image->columns,(MagickRealType) image->rows,MagickFalse,exception);
1645  shear_image->alpha_trait=image->alpha_trait;
1646  shear_image->compose=image->compose;
1647  shear_image->page.width=0;
1648  shear_image->page.height=0;
1649  if (status == MagickFalse)
1650  shear_image=DestroyImage(shear_image);
1651  return(shear_image);
1652 }
1653 
1654 /*
1655 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1656 % %
1657 % %
1658 % %
1659 % S h e a r R o t a t e I m a g e %
1660 % %
1661 % %
1662 % %
1663 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1664 %
1665 % ShearRotateImage() creates a new image that is a rotated copy of an existing
1666 % one. Positive angles rotate counter-clockwise (right-hand rule), while
1667 % negative angles rotate clockwise. Rotated images are usually larger than
1668 % the originals and have 'empty' triangular corners. X axis. Empty
1669 % triangles left over from shearing the image are filled with the background
1670 % color defined by member 'background_color' of the image. ShearRotateImage
1671 % allocates the memory necessary for the new Image structure and returns a
1672 % pointer to the new image.
1673 %
1674 % ShearRotateImage() is based on the paper "A Fast Algorithm for General
1675 % Raster Rotatation" by Alan W. Paeth. ShearRotateImage is adapted from a
1676 % similar method based on the Paeth paper written by Michael Halle of the
1677 % Spatial Imaging Group, MIT Media Lab.
1678 %
1679 % The format of the ShearRotateImage method is:
1680 %
1681 % Image *ShearRotateImage(const Image *image,const double degrees,
1682 % ExceptionInfo *exception)
1683 %
1684 % A description of each parameter follows.
1685 %
1686 % o image: the image.
1687 %
1688 % o degrees: Specifies the number of degrees to rotate the image.
1689 %
1690 % o exception: return any errors or warnings in this structure.
1691 %
1692 */
1693 MagickExport Image *ShearRotateImage(const Image *image,const double degrees,
1694  ExceptionInfo *exception)
1695 {
1696  Image
1697  *integral_image,
1698  *rotate_image;
1699 
1701  status;
1702 
1704  angle;
1705 
1706  PointInfo
1707  shear;
1708 
1710  border_info,
1711  bounds;
1712 
1713  size_t
1714  height,
1715  rotations,
1716  shear_width,
1717  width;
1718 
1719  /*
1720  Adjust rotation angle.
1721  */
1722  assert(image != (Image *) NULL);
1723  assert(image->signature == MagickCoreSignature);
1724  if (image->debug != MagickFalse)
1725  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1726  assert(exception != (ExceptionInfo *) NULL);
1727  assert(exception->signature == MagickCoreSignature);
1728  angle=fmod(degrees,360.0);
1729  if (angle < -45.0)
1730  angle+=360.0;
1731  for (rotations=0; angle > 45.0; rotations++)
1732  angle-=90.0;
1733  rotations%=4;
1734  /*
1735  Calculate shear equations.
1736  */
1737  integral_image=IntegralRotateImage(image,rotations,exception);
1738  if (integral_image == (Image *) NULL)
1739  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1740  shear.x=(-tan((double) DegreesToRadians(angle)/2.0));
1741  shear.y=sin((double) DegreesToRadians(angle));
1742  if ((shear.x == 0.0) && (shear.y == 0.0))
1743  return(integral_image);
1744  if (SetImageStorageClass(integral_image,DirectClass,exception) == MagickFalse)
1745  {
1746  integral_image=DestroyImage(integral_image);
1747  return(integral_image);
1748  }
1749  if (integral_image->alpha_trait == UndefinedPixelTrait)
1750  (void) SetImageAlphaChannel(integral_image,OpaqueAlphaChannel,exception);
1751  /*
1752  Compute maximum bounds for 3 shear operations.
1753  */
1754  width=integral_image->columns;
1755  height=integral_image->rows;
1756  bounds.width=(size_t) floor(fabs((double) height*shear.x)+width+0.5);
1757  bounds.height=(size_t) floor(fabs((double) bounds.width*shear.y)+height+0.5);
1758  shear_width=(size_t) floor(fabs((double) bounds.height*shear.x)+
1759  bounds.width+0.5);
1760  bounds.x=(ssize_t) floor((double) ((shear_width > bounds.width) ? width :
1761  bounds.width-shear_width+2)/2.0+0.5);
1762  bounds.y=(ssize_t) floor(((double) bounds.height-height+2)/2.0+0.5);
1763  /*
1764  Surround image with a border.
1765  */
1766  integral_image->border_color=integral_image->background_color;
1767  integral_image->compose=CopyCompositeOp;
1768  border_info.width=(size_t) bounds.x;
1769  border_info.height=(size_t) bounds.y;
1770  rotate_image=BorderImage(integral_image,&border_info,image->compose,
1771  exception);
1772  integral_image=DestroyImage(integral_image);
1773  if (rotate_image == (Image *) NULL)
1774  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1775  /*
1776  Rotate the image.
1777  */
1778  status=XShearImage(rotate_image,shear.x,width,height,bounds.x,(ssize_t)
1779  (rotate_image->rows-height)/2,exception);
1780  if (status == MagickFalse)
1781  {
1782  rotate_image=DestroyImage(rotate_image);
1783  return((Image *) NULL);
1784  }
1785  status=YShearImage(rotate_image,shear.y,bounds.width,height,(ssize_t)
1786  (rotate_image->columns-bounds.width)/2,bounds.y,exception);
1787  if (status == MagickFalse)
1788  {
1789  rotate_image=DestroyImage(rotate_image);
1790  return((Image *) NULL);
1791  }
1792  status=XShearImage(rotate_image,shear.x,bounds.width,bounds.height,(ssize_t)
1793  (rotate_image->columns-bounds.width)/2,(ssize_t) (rotate_image->rows-
1794  bounds.height)/2,exception);
1795  if (status == MagickFalse)
1796  {
1797  rotate_image=DestroyImage(rotate_image);
1798  return((Image *) NULL);
1799  }
1800  status=CropToFitImage(&rotate_image,shear.x,shear.y,(MagickRealType) width,
1801  (MagickRealType) height,MagickTrue,exception);
1802  rotate_image->alpha_trait=image->alpha_trait;
1803  rotate_image->compose=image->compose;
1804  rotate_image->page.width=0;
1805  rotate_image->page.height=0;
1806  if (status == MagickFalse)
1807  rotate_image=DestroyImage(rotate_image);
1808  return(rotate_image);
1809 }
size_t rows
Definition: image.h:172
#define magick_restrict
Definition: MagickCore.h:41
MagickDoubleType MagickRealType
Definition: magick-type.h:118
MagickExport CacheView * DestroyCacheView(CacheView *cache_view)
Definition: cache-view.c:252
static MagickBooleanType SetImageProgress(const Image *image, const char *tag, const MagickOffsetType offset, const MagickSizeType extent)
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:1693
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:1002
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:191
#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:1124
MagickExport ssize_t FormatLocaleString(char *magick_restrict string, const size_t length, const char *magick_restrict format,...)
Definition: locale.c:504
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:191
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:127
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:1109
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:533
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:966
MagickBooleanType
Definition: magick-type.h:156
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:533
static double DegreesToRadians(const double degrees)
Definition: image-private.h:56
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:1505
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:1340
MagickRealType blue
Definition: pixel.h:191
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:3438
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:1398
size_t signature
Definition: image.h:354
#define QuantumScale
Definition: magick-type.h:113
size_t columns
Definition: image.h:172
MagickBooleanType(* MagickProgressMonitor)(const char *, const MagickOffsetType, const MagickSizeType, void *)
Definition: monitor.h:26
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:2613
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 Quantum ClampToQuantum(const MagickRealType value)
Definition: quantum.h:84
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:1561
static double RadiansToDegrees(const double radians)
Definition: image-private.h:61
unsigned short Quantum
Definition: magick-type.h:82
MagickExport RectangleInfo GetImageBoundingBox(const Image *image, ExceptionInfo *exception)
Definition: attribute.c:125
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:1054
MagickRealType green
Definition: pixel.h:191
#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:135
PixelInfo background_color
Definition: image.h:179
MagickExport Image * DestroyImage(Image *image)
Definition: image.c:1177
MagickExport Image * CloneImage(const Image *image, const size_t columns, const size_t rows, const MagickBooleanType detach, ExceptionInfo *exception)
Definition: image.c:794
MagickExport Image * StatisticImage(const Image *image, const StatisticType type, const size_t width, const size_t height, ExceptionInfo *exception)
Definition: statistic.c:2831
#define QuantumRange
Definition: magick-type.h:83
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