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1 /*
2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 %                                                                             %
4 %                                                                             %
5 %                                                                             %
6 %    M   M    OOO    RRRR   PPPP   H   H   OOO   L       OOO    GGGG  Y   Y   %
7 %    MM MM   O   O   R   R  P   P  H   H  O   O  L      O   O  G       Y Y    %
8 %    M M M   O   O   RRRR   PPPP   HHHHH  O   O  L      O   O  G GGG    Y     %
9 %    M   M   O   O   R R    P      H   H  O   O  L      O   O  G   G    Y     %
10 %    M   M    OOO    R  R   P      H   H   OOO   LLLLL   OOO    GGG     Y     %
11 %                                                                             %
12 %                                                                             %
13 %                        MagickCore Morphology Methods                        %
14 %                                                                             %
15 %                              Software Design                                %
16 %                              Anthony Thyssen                                %
17 %                               January 2010                                  %
18 %                                                                             %
19 %                                                                             %
20 %  Copyright 1999-2019 ImageMagick Studio LLC, a non-profit organization      %
21 %  dedicated to making software imaging solutions freely available.           %
22 %                                                                             %
23 %  You may not use this file except in compliance with the License.  You may  %
24 %  obtain a copy of the License at                                            %
25 %                                                                             %
26 %    https://imagemagick.org/script/license.php                               %
27 %                                                                             %
28 %  Unless required by applicable law or agreed to in writing, software        %
29 %  distributed under the License is distributed on an "AS IS" BASIS,          %
30 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
31 %  See the License for the specific language governing permissions and        %
32 %  limitations under the License.                                             %
33 %                                                                             %
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
35 %
36 % Morphology is the application of various kernels, of any size or shape, to an
37 % image in various ways (typically binary, but not always).
38 %
39 % Convolution (weighted sum or average) is just one specific type of
40 % morphology. Just one that is very common for image bluring and sharpening
41 % effects.  Not only 2D Gaussian blurring, but also 2-pass 1D Blurring.
42 %
43 % This module provides not only a general morphology function, and the ability
44 % to apply more advanced or iterative morphologies, but also functions for the
45 % generation of many different types of kernel arrays from user supplied
46 % arguments. Prehaps even the generation of a kernel from a small image.
47 */
48 
49 /*
50   Include declarations.
51 */
52 #include "MagickCore/studio.h"
53 #include "MagickCore/artifact.h"
54 #include "MagickCore/cache-view.h"
55 #include "MagickCore/channel.h"
56 #include "MagickCore/color-private.h"
57 #include "MagickCore/enhance.h"
58 #include "MagickCore/exception.h"
59 #include "MagickCore/exception-private.h"
60 #include "MagickCore/gem.h"
61 #include "MagickCore/gem-private.h"
62 #include "MagickCore/image.h"
63 #include "MagickCore/image-private.h"
64 #include "MagickCore/linked-list.h"
65 #include "MagickCore/list.h"
66 #include "MagickCore/magick.h"
67 #include "MagickCore/memory_.h"
68 #include "MagickCore/memory-private.h"
69 #include "MagickCore/monitor-private.h"
70 #include "MagickCore/morphology.h"
71 #include "MagickCore/morphology-private.h"
72 #include "MagickCore/option.h"
73 #include "MagickCore/pixel-accessor.h"
74 #include "MagickCore/pixel-private.h"
75 #include "MagickCore/prepress.h"
76 #include "MagickCore/quantize.h"
77 #include "MagickCore/resource_.h"
78 #include "MagickCore/registry.h"
79 #include "MagickCore/semaphore.h"
80 #include "MagickCore/splay-tree.h"
81 #include "MagickCore/statistic.h"
82 #include "MagickCore/string_.h"
83 #include "MagickCore/string-private.h"
84 #include "MagickCore/thread-private.h"
85 #include "MagickCore/token.h"
86 #include "MagickCore/utility.h"
87 #include "MagickCore/utility-private.h"
88 
89 /*
90   Other global definitions used by module.
91 */
92 #define Minimize(assign,value) assign=MagickMin(assign,value)
93 #define Maximize(assign,value) assign=MagickMax(assign,value)
94 
95 /* Integer Factorial Function - for a Binomial kernel */
96 #if 1
fact(size_t n)97 static inline size_t fact(size_t n)
98 {
99   size_t f,l;
100   for(f=1, l=2; l <= n; f=f*l, l++);
101   return(f);
102 }
103 #elif 1 /* glibc floating point alternatives */
104 #define fact(n) ((size_t)tgamma((double)n+1))
105 #else
106 #define fact(n) ((size_t)lgamma((double)n+1))
107 #endif
108 
109 
110 /* Currently these are only internal to this module */
111 static void
112   CalcKernelMetaData(KernelInfo *),
113   ExpandMirrorKernelInfo(KernelInfo *),
114   ExpandRotateKernelInfo(KernelInfo *, const double),
115   RotateKernelInfo(KernelInfo *, double);
116 
117 
118 /* Quick function to find last kernel in a kernel list */
LastKernelInfo(KernelInfo * kernel)119 static inline KernelInfo *LastKernelInfo(KernelInfo *kernel)
120 {
121   while (kernel->next != (KernelInfo *) NULL)
122     kernel=kernel->next;
123   return(kernel);
124 }
125 
126 /*
127 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
128 %                                                                             %
129 %                                                                             %
130 %                                                                             %
131 %     A c q u i r e K e r n e l I n f o                                       %
132 %                                                                             %
133 %                                                                             %
134 %                                                                             %
135 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
136 %
137 %  AcquireKernelInfo() takes the given string (generally supplied by the
138 %  user) and converts it into a Morphology/Convolution Kernel.  This allows
139 %  users to specify a kernel from a number of pre-defined kernels, or to fully
140 %  specify their own kernel for a specific Convolution or Morphology
141 %  Operation.
142 %
143 %  The kernel so generated can be any rectangular array of floating point
144 %  values (doubles) with the 'control point' or 'pixel being affected'
145 %  anywhere within that array of values.
146 %
147 %  Previously IM was restricted to a square of odd size using the exact
148 %  center as origin, this is no longer the case, and any rectangular kernel
149 %  with any value being declared the origin. This in turn allows the use of
150 %  highly asymmetrical kernels.
151 %
152 %  The floating point values in the kernel can also include a special value
153 %  known as 'nan' or 'not a number' to indicate that this value is not part
154 %  of the kernel array. This allows you to shaped the kernel within its
155 %  rectangular area. That is 'nan' values provide a 'mask' for the kernel
156 %  shape.  However at least one non-nan value must be provided for correct
157 %  working of a kernel.
158 %
159 %  The returned kernel should be freed using the DestroyKernelInfo() when you
160 %  are finished with it.  Do not free this memory yourself.
161 %
162 %  Input kernel defintion strings can consist of any of three types.
163 %
164 %    "name:args[[@><]"
165 %         Select from one of the built in kernels, using the name and
166 %         geometry arguments supplied.  See AcquireKernelBuiltIn()
167 %
168 %    "WxH[+X+Y][@><]:num, num, num ..."
169 %         a kernel of size W by H, with W*H floating point numbers following.
170 %         the 'center' can be optionally be defined at +X+Y (such that +0+0
171 %         is top left corner). If not defined the pixel in the center, for
172 %         odd sizes, or to the immediate top or left of center for even sizes
173 %         is automatically selected.
174 %
175 %    "num, num, num, num, ..."
176 %         list of floating point numbers defining an 'old style' odd sized
177 %         square kernel.  At least 9 values should be provided for a 3x3
178 %         square kernel, 25 for a 5x5 square kernel, 49 for 7x7, etc.
179 %         Values can be space or comma separated.  This is not recommended.
180 %
181 %  You can define a 'list of kernels' which can be used by some morphology
182 %  operators A list is defined as a semi-colon separated list kernels.
183 %
184 %     " kernel ; kernel ; kernel ; "
185 %
186 %  Any extra ';' characters, at start, end or between kernel defintions are
187 %  simply ignored.
188 %
189 %  The special flags will expand a single kernel, into a list of rotated
190 %  kernels. A '@' flag will expand a 3x3 kernel into a list of 45-degree
191 %  cyclic rotations, while a '>' will generate a list of 90-degree rotations.
192 %  The '<' also exands using 90-degree rotates, but giving a 180-degree
193 %  reflected kernel before the +/- 90-degree rotations, which can be important
194 %  for Thinning operations.
195 %
196 %  Note that 'name' kernels will start with an alphabetic character while the
197 %  new kernel specification has a ':' character in its specification string.
198 %  If neither is the case, it is assumed an old style of a simple list of
199 %  numbers generating a odd-sized square kernel has been given.
200 %
201 %  The format of the AcquireKernal method is:
202 %
203 %      KernelInfo *AcquireKernelInfo(const char *kernel_string)
204 %
205 %  A description of each parameter follows:
206 %
207 %    o kernel_string: the Morphology/Convolution kernel wanted.
208 %
209 */
210 
211 /* This was separated so that it could be used as a separate
212 ** array input handling function, such as for -color-matrix
213 */
ParseKernelArray(const char * kernel_string)214 static KernelInfo *ParseKernelArray(const char *kernel_string)
215 {
216   KernelInfo
217     *kernel;
218 
219   char
220     token[MagickPathExtent];
221 
222   const char
223     *p,
224     *end;
225 
226   register ssize_t
227     i;
228 
229   double
230     nan = sqrt((double)-1.0);  /* Special Value : Not A Number */
231 
232   MagickStatusType
233     flags;
234 
235   GeometryInfo
236     args;
237 
238   kernel=(KernelInfo *) AcquireQuantumMemory(1,sizeof(*kernel));
239   if (kernel == (KernelInfo *) NULL)
240     return(kernel);
241   (void) memset(kernel,0,sizeof(*kernel));
242   kernel->minimum = kernel->maximum = kernel->angle = 0.0;
243   kernel->negative_range = kernel->positive_range = 0.0;
244   kernel->type = UserDefinedKernel;
245   kernel->next = (KernelInfo *) NULL;
246   kernel->signature=MagickCoreSignature;
247   if (kernel_string == (const char *) NULL)
248     return(kernel);
249 
250   /* find end of this specific kernel definition string */
251   end = strchr(kernel_string, ';');
252   if ( end == (char *) NULL )
253     end = strchr(kernel_string, '\0');
254 
255   /* clear flags - for Expanding kernel lists thorugh rotations */
256    flags = NoValue;
257 
258   /* Has a ':' in argument - New user kernel specification
259      FUTURE: this split on ':' could be done by StringToken()
260    */
261   p = strchr(kernel_string, ':');
262   if ( p != (char *) NULL && p < end)
263     {
264       /* ParseGeometry() needs the geometry separated! -- Arrgghh */
265       memcpy(token, kernel_string, (size_t) (p-kernel_string));
266       token[p-kernel_string] = '\0';
267       SetGeometryInfo(&args);
268       flags = ParseGeometry(token, &args);
269 
270       /* Size handling and checks of geometry settings */
271       if ( (flags & WidthValue) == 0 ) /* if no width then */
272         args.rho = args.sigma;         /* then  width = height */
273       if ( args.rho < 1.0 )            /* if width too small */
274          args.rho = 1.0;               /* then  width = 1 */
275       if ( args.sigma < 1.0 )          /* if height too small */
276         args.sigma = args.rho;         /* then  height = width */
277       kernel->width = (size_t)args.rho;
278       kernel->height = (size_t)args.sigma;
279 
280       /* Offset Handling and Checks */
281       if ( args.xi  < 0.0 || args.psi < 0.0 )
282         return(DestroyKernelInfo(kernel));
283       kernel->x = ((flags & XValue)!=0) ? (ssize_t)args.xi
284                                         : (ssize_t) (kernel->width-1)/2;
285       kernel->y = ((flags & YValue)!=0) ? (ssize_t)args.psi
286                                         : (ssize_t) (kernel->height-1)/2;
287       if ( kernel->x >= (ssize_t) kernel->width ||
288            kernel->y >= (ssize_t) kernel->height )
289         return(DestroyKernelInfo(kernel));
290 
291       p++; /* advance beyond the ':' */
292     }
293   else
294     { /* ELSE - Old old specification, forming odd-square kernel */
295       /* count up number of values given */
296       p=(const char *) kernel_string;
297       while ((isspace((int) ((unsigned char) *p)) != 0) || (*p == '\''))
298         p++;  /* ignore "'" chars for convolve filter usage - Cristy */
299       for (i=0; p < end; i++)
300       {
301         GetNextToken(p,&p,MagickPathExtent,token);
302         if (*token == ',')
303           GetNextToken(p,&p,MagickPathExtent,token);
304       }
305       /* set the size of the kernel - old sized square */
306       kernel->width = kernel->height= (size_t) sqrt((double) i+1.0);
307       kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
308       p=(const char *) kernel_string;
309       while ((isspace((int) ((unsigned char) *p)) != 0) || (*p == '\''))
310         p++;  /* ignore "'" chars for convolve filter usage - Cristy */
311     }
312 
313   /* Read in the kernel values from rest of input string argument */
314   kernel->values=(MagickRealType *) MagickAssumeAligned(AcquireAlignedMemory(
315     kernel->width,kernel->height*sizeof(*kernel->values)));
316   if (kernel->values == (MagickRealType *) NULL)
317     return(DestroyKernelInfo(kernel));
318   kernel->minimum=MagickMaximumValue;
319   kernel->maximum=(-MagickMaximumValue);
320   kernel->negative_range = kernel->positive_range = 0.0;
321   for (i=0; (i < (ssize_t) (kernel->width*kernel->height)) && (p < end); i++)
322   {
323     GetNextToken(p,&p,MagickPathExtent,token);
324     if (*token == ',')
325       GetNextToken(p,&p,MagickPathExtent,token);
326     if (    LocaleCompare("nan",token) == 0
327         || LocaleCompare("-",token) == 0 ) {
328       kernel->values[i] = nan; /* this value is not part of neighbourhood */
329     }
330     else {
331       kernel->values[i] = StringToDouble(token,(char **) NULL);
332       ( kernel->values[i] < 0)
333           ?  ( kernel->negative_range += kernel->values[i] )
334           :  ( kernel->positive_range += kernel->values[i] );
335       Minimize(kernel->minimum, kernel->values[i]);
336       Maximize(kernel->maximum, kernel->values[i]);
337     }
338   }
339 
340   /* sanity check -- no more values in kernel definition */
341   GetNextToken(p,&p,MagickPathExtent,token);
342   if ( *token != '\0' && *token != ';' && *token != '\'' )
343     return(DestroyKernelInfo(kernel));
344 
345 #if 0
346   /* this was the old method of handling a incomplete kernel */
347   if ( i < (ssize_t) (kernel->width*kernel->height) ) {
348     Minimize(kernel->minimum, kernel->values[i]);
349     Maximize(kernel->maximum, kernel->values[i]);
350     for ( ; i < (ssize_t) (kernel->width*kernel->height); i++)
351       kernel->values[i]=0.0;
352   }
353 #else
354   /* Number of values for kernel was not enough - Report Error */
355   if ( i < (ssize_t) (kernel->width*kernel->height) )
356     return(DestroyKernelInfo(kernel));
357 #endif
358 
359   /* check that we recieved at least one real (non-nan) value! */
360   if (kernel->minimum == MagickMaximumValue)
361     return(DestroyKernelInfo(kernel));
362 
363   if ( (flags & AreaValue) != 0 )         /* '@' symbol in kernel size */
364     ExpandRotateKernelInfo(kernel, 45.0); /* cyclic rotate 3x3 kernels */
365   else if ( (flags & GreaterValue) != 0 ) /* '>' symbol in kernel args */
366     ExpandRotateKernelInfo(kernel, 90.0); /* 90 degree rotate of kernel */
367   else if ( (flags & LessValue) != 0 )    /* '<' symbol in kernel args */
368     ExpandMirrorKernelInfo(kernel);       /* 90 degree mirror rotate */
369 
370   return(kernel);
371 }
372 
ParseKernelName(const char * kernel_string,ExceptionInfo * exception)373 static KernelInfo *ParseKernelName(const char *kernel_string,
374   ExceptionInfo *exception)
375 {
376   char
377     token[MagickPathExtent];
378 
379   const char
380     *p,
381     *end;
382 
383   GeometryInfo
384     args;
385 
386   KernelInfo
387     *kernel;
388 
389   MagickStatusType
390     flags;
391 
392   ssize_t
393     type;
394 
395   /* Parse special 'named' kernel */
396   GetNextToken(kernel_string,&p,MagickPathExtent,token);
397   type=ParseCommandOption(MagickKernelOptions,MagickFalse,token);
398   if ( type < 0 || type == UserDefinedKernel )
399     return((KernelInfo *) NULL);  /* not a valid named kernel */
400 
401   while (((isspace((int) ((unsigned char) *p)) != 0) ||
402           (*p == ',') || (*p == ':' )) && (*p != '\0') && (*p != ';'))
403     p++;
404 
405   end = strchr(p, ';'); /* end of this kernel defintion */
406   if ( end == (char *) NULL )
407     end = strchr(p, '\0');
408 
409   /* ParseGeometry() needs the geometry separated! -- Arrgghh */
410   memcpy(token, p, (size_t) (end-p));
411   token[end-p] = '\0';
412   SetGeometryInfo(&args);
413   flags = ParseGeometry(token, &args);
414 
415 #if 0
416   /* For Debugging Geometry Input */
417   (void) FormatLocaleFile(stderr, "Geometry = 0x%04X : %lg x %lg %+lg %+lg\n",
418     flags, args.rho, args.sigma, args.xi, args.psi );
419 #endif
420 
421   /* special handling of missing values in input string */
422   switch( type ) {
423     /* Shape Kernel Defaults */
424     case UnityKernel:
425       if ( (flags & WidthValue) == 0 )
426         args.rho = 1.0;    /* Default scale = 1.0, zero is valid */
427       break;
428     case SquareKernel:
429     case DiamondKernel:
430     case OctagonKernel:
431     case DiskKernel:
432     case PlusKernel:
433     case CrossKernel:
434       if ( (flags & HeightValue) == 0 )
435         args.sigma = 1.0;    /* Default scale = 1.0, zero is valid */
436       break;
437     case RingKernel:
438       if ( (flags & XValue) == 0 )
439         args.xi = 1.0;       /* Default scale = 1.0, zero is valid */
440       break;
441     case RectangleKernel:    /* Rectangle - set size defaults */
442       if ( (flags & WidthValue) == 0 ) /* if no width then */
443         args.rho = args.sigma;         /* then  width = height */
444       if ( args.rho < 1.0 )            /* if width too small */
445           args.rho = 3;                /* then  width = 3 */
446       if ( args.sigma < 1.0 )          /* if height too small */
447         args.sigma = args.rho;         /* then  height = width */
448       if ( (flags & XValue) == 0 )     /* center offset if not defined */
449         args.xi = (double)(((ssize_t)args.rho-1)/2);
450       if ( (flags & YValue) == 0 )
451         args.psi = (double)(((ssize_t)args.sigma-1)/2);
452       break;
453     /* Distance Kernel Defaults */
454     case ChebyshevKernel:
455     case ManhattanKernel:
456     case OctagonalKernel:
457     case EuclideanKernel:
458       if ( (flags & HeightValue) == 0 )           /* no distance scale */
459         args.sigma = 100.0;                       /* default distance scaling */
460       else if ( (flags & AspectValue ) != 0 )     /* '!' flag */
461         args.sigma = QuantumRange/(args.sigma+1); /* maximum pixel distance */
462       else if ( (flags & PercentValue ) != 0 )    /* '%' flag */
463         args.sigma *= QuantumRange/100.0;         /* percentage of color range */
464       break;
465     default:
466       break;
467   }
468 
469   kernel = AcquireKernelBuiltIn((KernelInfoType)type, &args, exception);
470   if ( kernel == (KernelInfo *) NULL )
471     return(kernel);
472 
473   /* global expand to rotated kernel list - only for single kernels */
474   if ( kernel->next == (KernelInfo *) NULL ) {
475     if ( (flags & AreaValue) != 0 )         /* '@' symbol in kernel args */
476       ExpandRotateKernelInfo(kernel, 45.0);
477     else if ( (flags & GreaterValue) != 0 ) /* '>' symbol in kernel args */
478       ExpandRotateKernelInfo(kernel, 90.0);
479     else if ( (flags & LessValue) != 0 )    /* '<' symbol in kernel args */
480       ExpandMirrorKernelInfo(kernel);
481   }
482 
483   return(kernel);
484 }
485 
AcquireKernelInfo(const char * kernel_string,ExceptionInfo * exception)486 MagickExport KernelInfo *AcquireKernelInfo(const char *kernel_string,
487   ExceptionInfo *exception)
488 {
489   KernelInfo
490     *kernel,
491     *new_kernel;
492 
493   char
494     *kernel_cache,
495     token[MagickPathExtent];
496 
497   const char
498     *p;
499 
500   if (kernel_string == (const char *) NULL)
501     return(ParseKernelArray(kernel_string));
502   p=kernel_string;
503   kernel_cache=(char *) NULL;
504   if (*kernel_string == '@')
505     {
506       kernel_cache=FileToString(kernel_string+1,~0UL,exception);
507       if (kernel_cache == (char *) NULL)
508         return((KernelInfo *) NULL);
509       p=(const char *) kernel_cache;
510     }
511   kernel=NULL;
512   while (GetNextToken(p,(const char **) NULL,MagickPathExtent,token), *token != '\0')
513   {
514     /* ignore extra or multiple ';' kernel separators */
515     if (*token != ';')
516       {
517         /* tokens starting with alpha is a Named kernel */
518         if (isalpha((int) ((unsigned char) *token)) != 0)
519           new_kernel=ParseKernelName(p,exception);
520         else /* otherwise a user defined kernel array */
521           new_kernel=ParseKernelArray(p);
522 
523         /* Error handling -- this is not proper error handling! */
524         if (new_kernel == (KernelInfo *) NULL)
525           {
526             if (kernel != (KernelInfo *) NULL)
527               kernel=DestroyKernelInfo(kernel);
528             return((KernelInfo *) NULL);
529           }
530 
531         /* initialise or append the kernel list */
532         if (kernel == (KernelInfo *) NULL)
533           kernel=new_kernel;
534         else
535           LastKernelInfo(kernel)->next=new_kernel;
536       }
537 
538     /* look for the next kernel in list */
539     p=strchr(p,';');
540     if (p == (char *) NULL)
541       break;
542     p++;
543   }
544   if (kernel_cache != (char *) NULL)
545     kernel_cache=DestroyString(kernel_cache);
546   return(kernel);
547 }
548 
549 /*
550 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
551 %                                                                             %
552 %                                                                             %
553 %                                                                             %
554 %     A c q u i r e K e r n e l B u i l t I n                                 %
555 %                                                                             %
556 %                                                                             %
557 %                                                                             %
558 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
559 %
560 %  AcquireKernelBuiltIn() returned one of the 'named' built-in types of
561 %  kernels used for special purposes such as gaussian blurring, skeleton
562 %  pruning, and edge distance determination.
563 %
564 %  They take a KernelType, and a set of geometry style arguments, which were
565 %  typically decoded from a user supplied string, or from a more complex
566 %  Morphology Method that was requested.
567 %
568 %  The format of the AcquireKernalBuiltIn method is:
569 %
570 %      KernelInfo *AcquireKernelBuiltIn(const KernelInfoType type,
571 %           const GeometryInfo args)
572 %
573 %  A description of each parameter follows:
574 %
575 %    o type: the pre-defined type of kernel wanted
576 %
577 %    o args: arguments defining or modifying the kernel
578 %
579 %  Convolution Kernels
580 %
581 %    Unity
582 %       The a No-Op or Scaling single element kernel.
583 %
584 %    Gaussian:{radius},{sigma}
585 %       Generate a two-dimensional gaussian kernel, as used by -gaussian.
586 %       The sigma for the curve is required.  The resulting kernel is
587 %       normalized,
588 %
589 %       If 'sigma' is zero, you get a single pixel on a field of zeros.
590 %
591 %       NOTE: that the 'radius' is optional, but if provided can limit (clip)
592 %       the final size of the resulting kernel to a square 2*radius+1 in size.
593 %       The radius should be at least 2 times that of the sigma value, or
594 %       sever clipping and aliasing may result.  If not given or set to 0 the
595 %       radius will be determined so as to produce the best minimal error
596 %       result, which is usally much larger than is normally needed.
597 %
598 %    LoG:{radius},{sigma}
599 %        "Laplacian of a Gaussian" or "Mexician Hat" Kernel.
600 %        The supposed ideal edge detection, zero-summing kernel.
601 %
602 %        An alturnative to this kernel is to use a "DoG" with a sigma ratio of
603 %        approx 1.6 (according to wikipedia).
604 %
605 %    DoG:{radius},{sigma1},{sigma2}
606 %        "Difference of Gaussians" Kernel.
607 %        As "Gaussian" but with a gaussian produced by 'sigma2' subtracted
608 %        from the gaussian produced by 'sigma1'. Typically sigma2 > sigma1.
609 %        The result is a zero-summing kernel.
610 %
611 %    Blur:{radius},{sigma}[,{angle}]
612 %       Generates a 1 dimensional or linear gaussian blur, at the angle given
613 %       (current restricted to orthogonal angles).  If a 'radius' is given the
614 %       kernel is clipped to a width of 2*radius+1.  Kernel can be rotated
615 %       by a 90 degree angle.
616 %
617 %       If 'sigma' is zero, you get a single pixel on a field of zeros.
618 %
619 %       Note that two convolutions with two "Blur" kernels perpendicular to
620 %       each other, is equivalent to a far larger "Gaussian" kernel with the
621 %       same sigma value, However it is much faster to apply. This is how the
622 %       "-blur" operator actually works.
623 %
624 %    Comet:{width},{sigma},{angle}
625 %       Blur in one direction only, much like how a bright object leaves
626 %       a comet like trail.  The Kernel is actually half a gaussian curve,
627 %       Adding two such blurs in opposite directions produces a Blur Kernel.
628 %       Angle can be rotated in multiples of 90 degrees.
629 %
630 %       Note that the first argument is the width of the kernel and not the
631 %       radius of the kernel.
632 %
633 %    Binomial:[{radius}]
634 %       Generate a discrete kernel using a 2 dimentional Pascel's Triangle
635 %       of values. Used for special forma of image filters.
636 %
637 %    # Still to be implemented...
638 %    #
639 %    # Filter2D
640 %    # Filter1D
641 %    #    Set kernel values using a resize filter, and given scale (sigma)
642 %    #    Cylindrical or Linear.   Is this possible with an image?
643 %    #
644 %
645 %  Named Constant Convolution Kernels
646 %
647 %  All these are unscaled, zero-summing kernels by default. As such for
648 %  non-HDRI version of ImageMagick some form of normalization, user scaling,
649 %  and biasing the results is recommended, to prevent the resulting image
650 %  being 'clipped'.
651 %
652 %  The 3x3 kernels (most of these) can be circularly rotated in multiples of
653 %  45 degrees to generate the 8 angled varients of each of the kernels.
654 %
655 %    Laplacian:{type}
656 %      Discrete Lapacian Kernels, (without normalization)
657 %        Type 0 :  3x3 with center:8 surounded by -1  (8 neighbourhood)
658 %        Type 1 :  3x3 with center:4 edge:-1 corner:0 (4 neighbourhood)
659 %        Type 2 :  3x3 with center:4 edge:1 corner:-2
660 %        Type 3 :  3x3 with center:4 edge:-2 corner:1
661 %        Type 5 :  5x5 laplacian
662 %        Type 7 :  7x7 laplacian
663 %        Type 15 : 5x5 LoG (sigma approx 1.4)
664 %        Type 19 : 9x9 LoG (sigma approx 1.4)
665 %
666 %    Sobel:{angle}
667 %      Sobel 'Edge' convolution kernel (3x3)
668 %          | -1, 0, 1 |
669 %          | -2, 0,-2 |
670 %          | -1, 0, 1 |
671 %
672 %    Roberts:{angle}
673 %      Roberts convolution kernel (3x3)
674 %          |  0, 0, 0 |
675 %          | -1, 1, 0 |
676 %          |  0, 0, 0 |
677 %
678 %    Prewitt:{angle}
679 %      Prewitt Edge convolution kernel (3x3)
680 %          | -1, 0, 1 |
681 %          | -1, 0, 1 |
682 %          | -1, 0, 1 |
683 %
684 %    Compass:{angle}
685 %      Prewitt's "Compass" convolution kernel (3x3)
686 %          | -1, 1, 1 |
687 %          | -1,-2, 1 |
688 %          | -1, 1, 1 |
689 %
690 %    Kirsch:{angle}
691 %      Kirsch's "Compass" convolution kernel (3x3)
692 %          | -3,-3, 5 |
693 %          | -3, 0, 5 |
694 %          | -3,-3, 5 |
695 %
696 %    FreiChen:{angle}
697 %      Frei-Chen Edge Detector is based on a kernel that is similar to
698 %      the Sobel Kernel, but is designed to be isotropic. That is it takes
699 %      into account the distance of the diagonal in the kernel.
700 %
701 %          |   1,     0,   -1     |
702 %          | sqrt(2), 0, -sqrt(2) |
703 %          |   1,     0,   -1     |
704 %
705 %    FreiChen:{type},{angle}
706 %
707 %      Frei-Chen Pre-weighted kernels...
708 %
709 %        Type 0:  default un-nomalized version shown above.
710 %
711 %        Type 1: Orthogonal Kernel (same as type 11 below)
712 %          |   1,     0,   -1     |
713 %          | sqrt(2), 0, -sqrt(2) | / 2*sqrt(2)
714 %          |   1,     0,   -1     |
715 %
716 %        Type 2: Diagonal form of Kernel...
717 %          |   1,     sqrt(2),    0     |
718 %          | sqrt(2),   0,     -sqrt(2) | / 2*sqrt(2)
719 %          |   0,    -sqrt(2)    -1     |
720 %
721 %      However this kernel is als at the heart of the FreiChen Edge Detection
722 %      Process which uses a set of 9 specially weighted kernel.  These 9
723 %      kernels not be normalized, but directly applied to the image. The
724 %      results is then added together, to produce the intensity of an edge in
725 %      a specific direction.  The square root of the pixel value can then be
726 %      taken as the cosine of the edge, and at least 2 such runs at 90 degrees
727 %      from each other, both the direction and the strength of the edge can be
728 %      determined.
729 %
730 %        Type 10: All 9 of the following pre-weighted kernels...
731 %
732 %        Type 11: |   1,     0,   -1     |
733 %                 | sqrt(2), 0, -sqrt(2) | / 2*sqrt(2)
734 %                 |   1,     0,   -1     |
735 %
736 %        Type 12: | 1, sqrt(2), 1 |
737 %                 | 0,   0,     0 | / 2*sqrt(2)
738 %                 | 1, sqrt(2), 1 |
739 %
740 %        Type 13: | sqrt(2), -1,    0     |
741 %                 |  -1,      0,    1     | / 2*sqrt(2)
742 %                 |   0,      1, -sqrt(2) |
743 %
744 %        Type 14: |    0,     1, -sqrt(2) |
745 %                 |   -1,     0,     1    | / 2*sqrt(2)
746 %                 | sqrt(2), -1,     0    |
747 %
748 %        Type 15: | 0, -1, 0 |
749 %                 | 1,  0, 1 | / 2
750 %                 | 0, -1, 0 |
751 %
752 %        Type 16: |  1, 0, -1 |
753 %                 |  0, 0,  0 | / 2
754 %                 | -1, 0,  1 |
755 %
756 %        Type 17: |  1, -2,  1 |
757 %                 | -2,  4, -2 | / 6
758 %                 | -1, -2,  1 |
759 %
760 %        Type 18: | -2, 1, -2 |
761 %                 |  1, 4,  1 | / 6
762 %                 | -2, 1, -2 |
763 %
764 %        Type 19: | 1, 1, 1 |
765 %                 | 1, 1, 1 | / 3
766 %                 | 1, 1, 1 |
767 %
768 %      The first 4 are for edge detection, the next 4 are for line detection
769 %      and the last is to add a average component to the results.
770 %
771 %      Using a special type of '-1' will return all 9 pre-weighted kernels
772 %      as a multi-kernel list, so that you can use them directly (without
773 %      normalization) with the special "-set option:morphology:compose Plus"
774 %      setting to apply the full FreiChen Edge Detection Technique.
775 %
776 %      If 'type' is large it will be taken to be an actual rotation angle for
777 %      the default FreiChen (type 0) kernel.  As such  FreiChen:45  will look
778 %      like a  Sobel:45  but with 'sqrt(2)' instead of '2' values.
779 %
780 %      WARNING: The above was layed out as per
781 %          http://www.math.tau.ac.il/~turkel/notes/edge_detectors.pdf
782 %      But rotated 90 degrees so direction is from left rather than the top.
783 %      I have yet to find any secondary confirmation of the above. The only
784 %      other source found was actual source code at
785 %          http://ltswww.epfl.ch/~courstiv/exos_labos/sol3.pdf
786 %      Neigher paper defineds the kernels in a way that looks locical or
787 %      correct when taken as a whole.
788 %
789 %  Boolean Kernels
790 %
791 %    Diamond:[{radius}[,{scale}]]
792 %       Generate a diamond shaped kernel with given radius to the points.
793 %       Kernel size will again be radius*2+1 square and defaults to radius 1,
794 %       generating a 3x3 kernel that is slightly larger than a square.
795 %
796 %    Square:[{radius}[,{scale}]]
797 %       Generate a square shaped kernel of size radius*2+1, and defaulting
798 %       to a 3x3 (radius 1).
799 %
800 %    Octagon:[{radius}[,{scale}]]
801 %       Generate octagonal shaped kernel of given radius and constant scale.
802 %       Default radius is 3 producing a 7x7 kernel. A radius of 1 will result
803 %       in "Diamond" kernel.
804 %
805 %    Disk:[{radius}[,{scale}]]
806 %       Generate a binary disk, thresholded at the radius given, the radius
807 %       may be a float-point value. Final Kernel size is floor(radius)*2+1
808 %       square. A radius of 5.3 is the default.
809 %
810 %       NOTE: That a low radii Disk kernels produce the same results as
811 %       many of the previously defined kernels, but differ greatly at larger
812 %       radii.  Here is a table of equivalences...
813 %          "Disk:1"    => "Diamond", "Octagon:1", or "Cross:1"
814 %          "Disk:1.5"  => "Square"
815 %          "Disk:2"    => "Diamond:2"
816 %          "Disk:2.5"  => "Octagon"
817 %          "Disk:2.9"  => "Square:2"
818 %          "Disk:3.5"  => "Octagon:3"
819 %          "Disk:4.5"  => "Octagon:4"
820 %          "Disk:5.4"  => "Octagon:5"
821 %          "Disk:6.4"  => "Octagon:6"
822 %       All other Disk shapes are unique to this kernel, but because a "Disk"
823 %       is more circular when using a larger radius, using a larger radius is
824 %       preferred over iterating the morphological operation.
825 %
826 %    Rectangle:{geometry}
827 %       Simply generate a rectangle of 1's with the size given. You can also
828 %       specify the location of the 'control point', otherwise the closest
829 %       pixel to the center of the rectangle is selected.
830 %
831 %       Properly centered and odd sized rectangles work the best.
832 %
833 %  Symbol Dilation Kernels
834 %
835 %    These kernel is not a good general morphological kernel, but is used
836 %    more for highlighting and marking any single pixels in an image using,
837 %    a "Dilate" method as appropriate.
838 %
839 %    For the same reasons iterating these kernels does not produce the
840 %    same result as using a larger radius for the symbol.
841 %
842 %    Plus:[{radius}[,{scale}]]
843 %    Cross:[{radius}[,{scale}]]
844 %       Generate a kernel in the shape of a 'plus' or a 'cross' with
845 %       a each arm the length of the given radius (default 2).
846 %
847 %       NOTE: "plus:1" is equivalent to a "Diamond" kernel.
848 %
849 %    Ring:{radius1},{radius2}[,{scale}]
850 %       A ring of the values given that falls between the two radii.
851 %       Defaults to a ring of approximataly 3 radius in a 7x7 kernel.
852 %       This is the 'edge' pixels of the default "Disk" kernel,
853 %       More specifically, "Ring" -> "Ring:2.5,3.5,1.0"
854 %
855 %  Hit and Miss Kernels
856 %
857 %    Peak:radius1,radius2
858 %       Find any peak larger than the pixels the fall between the two radii.
859 %       The default ring of pixels is as per "Ring".
860 %    Edges
861 %       Find flat orthogonal edges of a binary shape
862 %    Corners
863 %       Find 90 degree corners of a binary shape
864 %    Diagonals:type
865 %       A special kernel to thin the 'outside' of diagonals
866 %    LineEnds:type
867 %       Find end points of lines (for pruning a skeletion)
868 %       Two types of lines ends (default to both) can be searched for
869 %         Type 0: All line ends
870 %         Type 1: single kernel for 4-conneected line ends
871 %         Type 2: single kernel for simple line ends
872 %    LineJunctions
873 %       Find three line junctions (within a skeletion)
874 %         Type 0: all line junctions
875 %         Type 1: Y Junction kernel
876 %         Type 2: Diagonal T Junction kernel
877 %         Type 3: Orthogonal T Junction kernel
878 %         Type 4: Diagonal X Junction kernel
879 %         Type 5: Orthogonal + Junction kernel
880 %    Ridges:type
881 %       Find single pixel ridges or thin lines
882 %         Type 1: Fine single pixel thick lines and ridges
883 %         Type 2: Find two pixel thick lines and ridges
884 %    ConvexHull
885 %       Octagonal Thickening Kernel, to generate convex hulls of 45 degrees
886 %    Skeleton:type
887 %       Traditional skeleton generating kernels.
888 %         Type 1: Tradional Skeleton kernel (4 connected skeleton)
889 %         Type 2: HIPR2 Skeleton kernel (8 connected skeleton)
890 %         Type 3: Thinning skeleton based on a ressearch paper by
891 %                 Dan S. Bloomberg (Default Type)
892 %    ThinSE:type
893 %       A huge variety of Thinning Kernels designed to preserve conectivity.
894 %       many other kernel sets use these kernels as source definitions.
895 %       Type numbers are 41-49, 81-89, 481, and 482 which are based on
896 %       the super and sub notations used in the source research paper.
897 %
898 %  Distance Measuring Kernels
899 %
900 %    Different types of distance measuring methods, which are used with the
901 %    a 'Distance' morphology method for generating a gradient based on
902 %    distance from an edge of a binary shape, though there is a technique
903 %    for handling a anti-aliased shape.
904 %
905 %    See the 'Distance' Morphological Method, for information of how it is
906 %    applied.
907 %
908 %    Chebyshev:[{radius}][x{scale}[%!]]
909 %       Chebyshev Distance (also known as Tchebychev or Chessboard distance)
910 %       is a value of one to any neighbour, orthogonal or diagonal. One why
911 %       of thinking of it is the number of squares a 'King' or 'Queen' in
912 %       chess needs to traverse reach any other position on a chess board.
913 %       It results in a 'square' like distance function, but one where
914 %       diagonals are given a value that is closer than expected.
915 %
916 %    Manhattan:[{radius}][x{scale}[%!]]
917 %       Manhattan Distance (also known as Rectilinear, City Block, or the Taxi
918 %       Cab distance metric), it is the distance needed when you can only
919 %       travel in horizontal or vertical directions only.  It is the
920 %       distance a 'Rook' in chess would have to travel, and results in a
921 %       diamond like distances, where diagonals are further than expected.
922 %
923 %    Octagonal:[{radius}][x{scale}[%!]]
924 %       An interleving of Manhatten and Chebyshev metrics producing an
925 %       increasing octagonally shaped distance.  Distances matches those of
926 %       the "Octagon" shaped kernel of the same radius.  The minimum radius
927 %       and default is 2, producing a 5x5 kernel.
928 %
929 %    Euclidean:[{radius}][x{scale}[%!]]
930 %       Euclidean distance is the 'direct' or 'as the crow flys' distance.
931 %       However by default the kernel size only has a radius of 1, which
932 %       limits the distance to 'Knight' like moves, with only orthogonal and
933 %       diagonal measurements being correct.  As such for the default kernel
934 %       you will get octagonal like distance function.
935 %
936 %       However using a larger radius such as "Euclidean:4" you will get a
937 %       much smoother distance gradient from the edge of the shape. Especially
938 %       if the image is pre-processed to include any anti-aliasing pixels.
939 %       Of course a larger kernel is slower to use, and not always needed.
940 %
941 %    The first three Distance Measuring Kernels will only generate distances
942 %    of exact multiples of {scale} in binary images. As such you can use a
943 %    scale of 1 without loosing any information.  However you also need some
944 %    scaling when handling non-binary anti-aliased shapes.
945 %
946 %    The "Euclidean" Distance Kernel however does generate a non-integer
947 %    fractional results, and as such scaling is vital even for binary shapes.
948 %
949 */
950 
AcquireKernelBuiltIn(const KernelInfoType type,const GeometryInfo * args,ExceptionInfo * exception)951 MagickExport KernelInfo *AcquireKernelBuiltIn(const KernelInfoType type,
952   const GeometryInfo *args,ExceptionInfo *exception)
953 {
954   KernelInfo
955     *kernel;
956 
957   register ssize_t
958     i;
959 
960   register ssize_t
961     u,
962     v;
963 
964   double
965     nan = sqrt((double)-1.0);  /* Special Value : Not A Number */
966 
967   /* Generate a new empty kernel if needed */
968   kernel=(KernelInfo *) NULL;
969   switch(type) {
970     case UndefinedKernel:    /* These should not call this function */
971     case UserDefinedKernel:
972       assert("Should not call this function" != (char *) NULL);
973       break;
974     case LaplacianKernel:   /* Named Descrete Convolution Kernels */
975     case SobelKernel:       /* these are defined using other kernels */
976     case RobertsKernel:
977     case PrewittKernel:
978     case CompassKernel:
979     case KirschKernel:
980     case FreiChenKernel:
981     case EdgesKernel:       /* Hit and Miss kernels */
982     case CornersKernel:
983     case DiagonalsKernel:
984     case LineEndsKernel:
985     case LineJunctionsKernel:
986     case RidgesKernel:
987     case ConvexHullKernel:
988     case SkeletonKernel:
989     case ThinSEKernel:
990       break;               /* A pre-generated kernel is not needed */
991 #if 0
992     /* set to 1 to do a compile-time check that we haven't missed anything */
993     case UnityKernel:
994     case GaussianKernel:
995     case DoGKernel:
996     case LoGKernel:
997     case BlurKernel:
998     case CometKernel:
999     case BinomialKernel:
1000     case DiamondKernel:
1001     case SquareKernel:
1002     case RectangleKernel:
1003     case OctagonKernel:
1004     case DiskKernel:
1005     case PlusKernel:
1006     case CrossKernel:
1007     case RingKernel:
1008     case PeaksKernel:
1009     case ChebyshevKernel:
1010     case ManhattanKernel:
1011     case OctangonalKernel:
1012     case EuclideanKernel:
1013 #else
1014     default:
1015 #endif
1016       /* Generate the base Kernel Structure */
1017       kernel=(KernelInfo *) AcquireMagickMemory(sizeof(*kernel));
1018       if (kernel == (KernelInfo *) NULL)
1019         return(kernel);
1020       (void) memset(kernel,0,sizeof(*kernel));
1021       kernel->minimum = kernel->maximum = kernel->angle = 0.0;
1022       kernel->negative_range = kernel->positive_range = 0.0;
1023       kernel->type = type;
1024       kernel->next = (KernelInfo *) NULL;
1025       kernel->signature=MagickCoreSignature;
1026       break;
1027   }
1028 
1029   switch(type) {
1030     /*
1031       Convolution Kernels
1032     */
1033     case UnityKernel:
1034       {
1035         kernel->height = kernel->width = (size_t) 1;
1036         kernel->x = kernel->y = (ssize_t) 0;
1037         kernel->values=(MagickRealType *) MagickAssumeAligned(
1038           AcquireAlignedMemory(1,sizeof(*kernel->values)));
1039         if (kernel->values == (MagickRealType *) NULL)
1040           return(DestroyKernelInfo(kernel));
1041         kernel->maximum = kernel->values[0] = args->rho;
1042         break;
1043       }
1044       break;
1045     case GaussianKernel:
1046     case DoGKernel:
1047     case LoGKernel:
1048       { double
1049           sigma = fabs(args->sigma),
1050           sigma2 = fabs(args->xi),
1051           A, B, R;
1052 
1053         if ( args->rho >= 1.0 )
1054           kernel->width = (size_t)args->rho*2+1;
1055         else if ( (type != DoGKernel) || (sigma >= sigma2) )
1056           kernel->width = GetOptimalKernelWidth2D(args->rho,sigma);
1057         else
1058           kernel->width = GetOptimalKernelWidth2D(args->rho,sigma2);
1059         kernel->height = kernel->width;
1060         kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1061         kernel->values=(MagickRealType *) MagickAssumeAligned(
1062           AcquireAlignedMemory(kernel->width,kernel->height*
1063           sizeof(*kernel->values)));
1064         if (kernel->values == (MagickRealType *) NULL)
1065           return(DestroyKernelInfo(kernel));
1066 
1067         /* WARNING: The following generates a 'sampled gaussian' kernel.
1068          * What we really want is a 'discrete gaussian' kernel.
1069          *
1070          * How to do this is I don't know, but appears to be basied on the
1071          * Error Function 'erf()' (intergral of a gaussian)
1072          */
1073 
1074         if ( type == GaussianKernel || type == DoGKernel )
1075           { /* Calculate a Gaussian,  OR positive half of a DoG */
1076             if ( sigma > MagickEpsilon )
1077               { A = 1.0/(2.0*sigma*sigma);  /* simplify loop expressions */
1078                 B = (double) (1.0/(Magick2PI*sigma*sigma));
1079                 for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1080                   for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1081                       kernel->values[i] = exp(-((double)(u*u+v*v))*A)*B;
1082               }
1083             else /* limiting case - a unity (normalized Dirac) kernel */
1084               { (void) memset(kernel->values,0, (size_t)
1085                   kernel->width*kernel->height*sizeof(*kernel->values));
1086                 kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
1087               }
1088           }
1089 
1090         if ( type == DoGKernel )
1091           { /* Subtract a Negative Gaussian for "Difference of Gaussian" */
1092             if ( sigma2 > MagickEpsilon )
1093               { sigma = sigma2;                /* simplify loop expressions */
1094                 A = 1.0/(2.0*sigma*sigma);
1095                 B = (double) (1.0/(Magick2PI*sigma*sigma));
1096                 for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1097                   for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1098                     kernel->values[i] -= exp(-((double)(u*u+v*v))*A)*B;
1099               }
1100             else /* limiting case - a unity (normalized Dirac) kernel */
1101               kernel->values[kernel->x+kernel->y*kernel->width] -= 1.0;
1102           }
1103 
1104         if ( type == LoGKernel )
1105           { /* Calculate a Laplacian of a Gaussian - Or Mexician Hat */
1106             if ( sigma > MagickEpsilon )
1107               { A = 1.0/(2.0*sigma*sigma);  /* simplify loop expressions */
1108                 B = (double) (1.0/(MagickPI*sigma*sigma*sigma*sigma));
1109                 for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1110                   for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1111                     { R = ((double)(u*u+v*v))*A;
1112                       kernel->values[i] = (1-R)*exp(-R)*B;
1113                     }
1114               }
1115             else /* special case - generate a unity kernel */
1116               { (void) memset(kernel->values,0, (size_t)
1117                   kernel->width*kernel->height*sizeof(*kernel->values));
1118                 kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
1119               }
1120           }
1121 
1122         /* Note the above kernels may have been 'clipped' by a user defined
1123         ** radius, producing a smaller (darker) kernel.  Also for very small
1124         ** sigma's (> 0.1) the central value becomes larger than one, and thus
1125         ** producing a very bright kernel.
1126         **
1127         ** Normalization will still be needed.
1128         */
1129 
1130         /* Normalize the 2D Gaussian Kernel
1131         **
1132         ** NB: a CorrelateNormalize performs a normal Normalize if
1133         ** there are no negative values.
1134         */
1135         CalcKernelMetaData(kernel);  /* the other kernel meta-data */
1136         ScaleKernelInfo(kernel, 1.0, CorrelateNormalizeValue);
1137 
1138         break;
1139       }
1140     case BlurKernel:
1141       { double
1142           sigma = fabs(args->sigma),
1143           alpha, beta;
1144 
1145         if ( args->rho >= 1.0 )
1146           kernel->width = (size_t)args->rho*2+1;
1147         else
1148           kernel->width = GetOptimalKernelWidth1D(args->rho,sigma);
1149         kernel->height = 1;
1150         kernel->x = (ssize_t) (kernel->width-1)/2;
1151         kernel->y = 0;
1152         kernel->negative_range = kernel->positive_range = 0.0;
1153         kernel->values=(MagickRealType *) MagickAssumeAligned(
1154           AcquireAlignedMemory(kernel->width,kernel->height*
1155           sizeof(*kernel->values)));
1156         if (kernel->values == (MagickRealType *) NULL)
1157           return(DestroyKernelInfo(kernel));
1158 
1159 #if 1
1160 #define KernelRank 3
1161         /* Formula derived from GetBlurKernel() in "effect.c" (plus bug fix).
1162         ** It generates a gaussian 3 times the width, and compresses it into
1163         ** the expected range.  This produces a closer normalization of the
1164         ** resulting kernel, especially for very low sigma values.
1165         ** As such while wierd it is prefered.
1166         **
1167         ** I am told this method originally came from Photoshop.
1168         **
1169         ** A properly normalized curve is generated (apart from edge clipping)
1170         ** even though we later normalize the result (for edge clipping)
1171         ** to allow the correct generation of a "Difference of Blurs".
1172         */
1173 
1174         /* initialize */
1175         v = (ssize_t) (kernel->width*KernelRank-1)/2; /* start/end points to fit range */
1176         (void) memset(kernel->values,0, (size_t)
1177           kernel->width*kernel->height*sizeof(*kernel->values));
1178         /* Calculate a Positive 1D Gaussian */
1179         if ( sigma > MagickEpsilon )
1180           { sigma *= KernelRank;               /* simplify loop expressions */
1181             alpha = 1.0/(2.0*sigma*sigma);
1182             beta= (double) (1.0/(MagickSQ2PI*sigma ));
1183             for ( u=-v; u <= v; u++) {
1184               kernel->values[(u+v)/KernelRank] +=
1185                               exp(-((double)(u*u))*alpha)*beta;
1186             }
1187           }
1188         else /* special case - generate a unity kernel */
1189           kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
1190 #else
1191         /* Direct calculation without curve averaging
1192            This is equivelent to a KernelRank of 1 */
1193 
1194         /* Calculate a Positive Gaussian */
1195         if ( sigma > MagickEpsilon )
1196           { alpha = 1.0/(2.0*sigma*sigma);    /* simplify loop expressions */
1197             beta = 1.0/(MagickSQ2PI*sigma);
1198             for ( i=0, u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1199               kernel->values[i] = exp(-((double)(u*u))*alpha)*beta;
1200           }
1201         else /* special case - generate a unity kernel */
1202           { (void) memset(kernel->values,0, (size_t)
1203               kernel->width*kernel->height*sizeof(*kernel->values));
1204             kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
1205           }
1206 #endif
1207         /* Note the above kernel may have been 'clipped' by a user defined
1208         ** radius, producing a smaller (darker) kernel.  Also for very small
1209         ** sigma's (> 0.1) the central value becomes larger than one, as a
1210         ** result of not generating a actual 'discrete' kernel, and thus
1211         ** producing a very bright 'impulse'.
1212         **
1213         ** Becuase of these two factors Normalization is required!
1214         */
1215 
1216         /* Normalize the 1D Gaussian Kernel
1217         **
1218         ** NB: a CorrelateNormalize performs a normal Normalize if
1219         ** there are no negative values.
1220         */
1221         CalcKernelMetaData(kernel);  /* the other kernel meta-data */
1222         ScaleKernelInfo(kernel, 1.0, CorrelateNormalizeValue);
1223 
1224         /* rotate the 1D kernel by given angle */
1225         RotateKernelInfo(kernel, args->xi );
1226         break;
1227       }
1228     case CometKernel:
1229       { double
1230           sigma = fabs(args->sigma),
1231           A;
1232 
1233         if ( args->rho < 1.0 )
1234           kernel->width = (GetOptimalKernelWidth1D(args->rho,sigma)-1)/2+1;
1235         else
1236           kernel->width = (size_t)args->rho;
1237         kernel->x = kernel->y = 0;
1238         kernel->height = 1;
1239         kernel->negative_range = kernel->positive_range = 0.0;
1240         kernel->values=(MagickRealType *) MagickAssumeAligned(
1241           AcquireAlignedMemory(kernel->width,kernel->height*
1242           sizeof(*kernel->values)));
1243         if (kernel->values == (MagickRealType *) NULL)
1244           return(DestroyKernelInfo(kernel));
1245 
1246         /* A comet blur is half a 1D gaussian curve, so that the object is
1247         ** blurred in one direction only.  This may not be quite the right
1248         ** curve to use so may change in the future. The function must be
1249         ** normalised after generation, which also resolves any clipping.
1250         **
1251         ** As we are normalizing and not subtracting gaussians,
1252         ** there is no need for a divisor in the gaussian formula
1253         **
1254         ** It is less comples
1255         */
1256         if ( sigma > MagickEpsilon )
1257           {
1258 #if 1
1259 #define KernelRank 3
1260             v = (ssize_t) kernel->width*KernelRank; /* start/end points */
1261             (void) memset(kernel->values,0, (size_t)
1262               kernel->width*sizeof(*kernel->values));
1263             sigma *= KernelRank;            /* simplify the loop expression */
1264             A = 1.0/(2.0*sigma*sigma);
1265             /* B = 1.0/(MagickSQ2PI*sigma); */
1266             for ( u=0; u < v; u++) {
1267               kernel->values[u/KernelRank] +=
1268                   exp(-((double)(u*u))*A);
1269               /*  exp(-((double)(i*i))/2.0*sigma*sigma)/(MagickSQ2PI*sigma); */
1270             }
1271             for (i=0; i < (ssize_t) kernel->width; i++)
1272               kernel->positive_range += kernel->values[i];
1273 #else
1274             A = 1.0/(2.0*sigma*sigma);     /* simplify the loop expression */
1275             /* B = 1.0/(MagickSQ2PI*sigma); */
1276             for ( i=0; i < (ssize_t) kernel->width; i++)
1277               kernel->positive_range +=
1278                 kernel->values[i] = exp(-((double)(i*i))*A);
1279                 /* exp(-((double)(i*i))/2.0*sigma*sigma)/(MagickSQ2PI*sigma); */
1280 #endif
1281           }
1282         else /* special case - generate a unity kernel */
1283           { (void) memset(kernel->values,0, (size_t)
1284               kernel->width*kernel->height*sizeof(*kernel->values));
1285             kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
1286             kernel->positive_range = 1.0;
1287           }
1288 
1289         kernel->minimum = 0.0;
1290         kernel->maximum = kernel->values[0];
1291         kernel->negative_range = 0.0;
1292 
1293         ScaleKernelInfo(kernel, 1.0, NormalizeValue); /* Normalize */
1294         RotateKernelInfo(kernel, args->xi); /* Rotate by angle */
1295         break;
1296       }
1297     case BinomialKernel:
1298       {
1299         size_t
1300           order_f;
1301 
1302         if (args->rho < 1.0)
1303           kernel->width = kernel->height = 3;  /* default radius = 1 */
1304         else
1305           kernel->width = kernel->height = ((size_t)args->rho)*2+1;
1306         kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1307 
1308         order_f = fact(kernel->width-1);
1309 
1310         kernel->values=(MagickRealType *) MagickAssumeAligned(
1311           AcquireAlignedMemory(kernel->width,kernel->height*
1312           sizeof(*kernel->values)));
1313         if (kernel->values == (MagickRealType *) NULL)
1314           return(DestroyKernelInfo(kernel));
1315 
1316         /* set all kernel values within diamond area to scale given */
1317         for ( i=0, v=0; v < (ssize_t)kernel->height; v++)
1318           { size_t
1319               alpha = order_f / ( fact((size_t) v) * fact(kernel->height-v-1) );
1320             for ( u=0; u < (ssize_t)kernel->width; u++, i++)
1321               kernel->positive_range += kernel->values[i] = (double)
1322                 (alpha * order_f / ( fact((size_t) u) * fact(kernel->height-u-1) ));
1323           }
1324         kernel->minimum = 1.0;
1325         kernel->maximum = kernel->values[kernel->x+kernel->y*kernel->width];
1326         kernel->negative_range = 0.0;
1327         break;
1328       }
1329 
1330     /*
1331       Convolution Kernels - Well Known Named Constant Kernels
1332     */
1333     case LaplacianKernel:
1334       { switch ( (int) args->rho ) {
1335           case 0:
1336           default: /* laplacian square filter -- default */
1337             kernel=ParseKernelArray("3: -1,-1,-1  -1,8,-1  -1,-1,-1");
1338             break;
1339           case 1:  /* laplacian diamond filter */
1340             kernel=ParseKernelArray("3: 0,-1,0  -1,4,-1  0,-1,0");
1341             break;
1342           case 2:
1343             kernel=ParseKernelArray("3: -2,1,-2  1,4,1  -2,1,-2");
1344             break;
1345           case 3:
1346             kernel=ParseKernelArray("3: 1,-2,1  -2,4,-2  1,-2,1");
1347             break;
1348           case 5:   /* a 5x5 laplacian */
1349             kernel=ParseKernelArray(
1350               "5: -4,-1,0,-1,-4  -1,2,3,2,-1  0,3,4,3,0  -1,2,3,2,-1  -4,-1,0,-1,-4");
1351             break;
1352           case 7:   /* a 7x7 laplacian */
1353             kernel=ParseKernelArray(
1354               "7:-10,-5,-2,-1,-2,-5,-10 -5,0,3,4,3,0,-5 -2,3,6,7,6,3,-2 -1,4,7,8,7,4,-1 -2,3,6,7,6,3,-2 -5,0,3,4,3,0,-5 -10,-5,-2,-1,-2,-5,-10" );
1355             break;
1356           case 15:  /* a 5x5 LoG (sigma approx 1.4) */
1357             kernel=ParseKernelArray(
1358               "5: 0,0,-1,0,0  0,-1,-2,-1,0  -1,-2,16,-2,-1  0,-1,-2,-1,0  0,0,-1,0,0");
1359             break;
1360           case 19:  /* a 9x9 LoG (sigma approx 1.4) */
1361             /* http://www.cscjournals.org/csc/manuscript/Journals/IJIP/volume3/Issue1/IJIP-15.pdf */
1362             kernel=ParseKernelArray(
1363               "9: 0,-1,-1,-2,-2,-2,-1,-1,0  -1,-2,-4,-5,-5,-5,-4,-2,-1  -1,-4,-5,-3,-0,-3,-5,-4,-1  -2,-5,-3,12,24,12,-3,-5,-2  -2,-5,-0,24,40,24,-0,-5,-2  -2,-5,-3,12,24,12,-3,-5,-2  -1,-4,-5,-3,-0,-3,-5,-4,-1  -1,-2,-4,-5,-5,-5,-4,-2,-1  0,-1,-1,-2,-2,-2,-1,-1,0");
1364             break;
1365         }
1366         if (kernel == (KernelInfo *) NULL)
1367           return(kernel);
1368         kernel->type = type;
1369         break;
1370       }
1371     case SobelKernel:
1372       { /* Simple Sobel Kernel */
1373         kernel=ParseKernelArray("3: 1,0,-1  2,0,-2  1,0,-1");
1374         if (kernel == (KernelInfo *) NULL)
1375           return(kernel);
1376         kernel->type = type;
1377         RotateKernelInfo(kernel, args->rho);
1378         break;
1379       }
1380     case RobertsKernel:
1381       {
1382         kernel=ParseKernelArray("3: 0,0,0  1,-1,0  0,0,0");
1383         if (kernel == (KernelInfo *) NULL)
1384           return(kernel);
1385         kernel->type = type;
1386         RotateKernelInfo(kernel, args->rho);
1387         break;
1388       }
1389     case PrewittKernel:
1390       {
1391         kernel=ParseKernelArray("3: 1,0,-1  1,0,-1  1,0,-1");
1392         if (kernel == (KernelInfo *) NULL)
1393           return(kernel);
1394         kernel->type = type;
1395         RotateKernelInfo(kernel, args->rho);
1396         break;
1397       }
1398     case CompassKernel:
1399       {
1400         kernel=ParseKernelArray("3: 1,1,-1  1,-2,-1  1,1,-1");
1401         if (kernel == (KernelInfo *) NULL)
1402           return(kernel);
1403         kernel->type = type;
1404         RotateKernelInfo(kernel, args->rho);
1405         break;
1406       }
1407     case KirschKernel:
1408       {
1409         kernel=ParseKernelArray("3: 5,-3,-3  5,0,-3  5,-3,-3");
1410         if (kernel == (KernelInfo *) NULL)
1411           return(kernel);
1412         kernel->type = type;
1413         RotateKernelInfo(kernel, args->rho);
1414         break;
1415       }
1416     case FreiChenKernel:
1417       /* Direction is set to be left to right positive */
1418       /* http://www.math.tau.ac.il/~turkel/notes/edge_detectors.pdf -- RIGHT? */
1419       /* http://ltswww.epfl.ch/~courstiv/exos_labos/sol3.pdf -- WRONG? */
1420       { switch ( (int) args->rho ) {
1421           default:
1422           case 0:
1423             kernel=ParseKernelArray("3: 1,0,-1  2,0,-2  1,0,-1");
1424             if (kernel == (KernelInfo *) NULL)
1425               return(kernel);
1426             kernel->type = type;
1427             kernel->values[3] = +(MagickRealType) MagickSQ2;
1428             kernel->values[5] = -(MagickRealType) MagickSQ2;
1429             CalcKernelMetaData(kernel);     /* recalculate meta-data */
1430             break;
1431           case 2:
1432             kernel=ParseKernelArray("3: 1,2,0  2,0,-2  0,-2,-1");
1433             if (kernel == (KernelInfo *) NULL)
1434               return(kernel);
1435             kernel->type = type;
1436             kernel->values[1] = kernel->values[3]= +(MagickRealType) MagickSQ2;
1437             kernel->values[5] = kernel->values[7]= -(MagickRealType) MagickSQ2;
1438             CalcKernelMetaData(kernel);     /* recalculate meta-data */
1439             ScaleKernelInfo(kernel, (double) (1.0/2.0*MagickSQ2), NoValue);
1440             break;
1441           case 10:
1442           {
1443             kernel=AcquireKernelInfo("FreiChen:11;FreiChen:12;FreiChen:13;FreiChen:14;FreiChen:15;FreiChen:16;FreiChen:17;FreiChen:18;FreiChen:19",exception);
1444             if (kernel == (KernelInfo *) NULL)
1445               return(kernel);
1446             break;
1447           }
1448           case 1:
1449           case 11:
1450             kernel=ParseKernelArray("3: 1,0,-1  2,0,-2  1,0,-1");
1451             if (kernel == (KernelInfo *) NULL)
1452               return(kernel);
1453             kernel->type = type;
1454             kernel->values[3] = +(MagickRealType) MagickSQ2;
1455             kernel->values[5] = -(MagickRealType) MagickSQ2;
1456             CalcKernelMetaData(kernel);     /* recalculate meta-data */
1457             ScaleKernelInfo(kernel, (double) (1.0/2.0*MagickSQ2), NoValue);
1458             break;
1459           case 12:
1460             kernel=ParseKernelArray("3: 1,2,1  0,0,0  1,2,1");
1461             if (kernel == (KernelInfo *) NULL)
1462               return(kernel);
1463             kernel->type = type;
1464             kernel->values[1] = +(MagickRealType) MagickSQ2;
1465             kernel->values[7] = +(MagickRealType) MagickSQ2;
1466             CalcKernelMetaData(kernel);
1467             ScaleKernelInfo(kernel, (double) (1.0/2.0*MagickSQ2), NoValue);
1468             break;
1469           case 13:
1470             kernel=ParseKernelArray("3: 2,-1,0  -1,0,1  0,1,-2");
1471             if (kernel == (KernelInfo *) NULL)
1472               return(kernel);
1473             kernel->type = type;
1474             kernel->values[0] = +(MagickRealType) MagickSQ2;
1475             kernel->values[8] = -(MagickRealType) MagickSQ2;
1476             CalcKernelMetaData(kernel);
1477             ScaleKernelInfo(kernel, (double) (1.0/2.0*MagickSQ2), NoValue);
1478             break;
1479           case 14:
1480             kernel=ParseKernelArray("3: 0,1,-2  -1,0,1  2,-1,0");
1481             if (kernel == (KernelInfo *) NULL)
1482               return(kernel);
1483             kernel->type = type;
1484             kernel->values[2] = -(MagickRealType) MagickSQ2;
1485             kernel->values[6] = +(MagickRealType) MagickSQ2;
1486             CalcKernelMetaData(kernel);
1487             ScaleKernelInfo(kernel, (double) (1.0/2.0*MagickSQ2), NoValue);
1488             break;
1489           case 15:
1490             kernel=ParseKernelArray("3: 0,-1,0  1,0,1  0,-1,0");
1491             if (kernel == (KernelInfo *) NULL)
1492               return(kernel);
1493             kernel->type = type;
1494             ScaleKernelInfo(kernel, 1.0/2.0, NoValue);
1495             break;
1496           case 16:
1497             kernel=ParseKernelArray("3: 1,0,-1  0,0,0  -1,0,1");
1498             if (kernel == (KernelInfo *) NULL)
1499               return(kernel);
1500             kernel->type = type;
1501             ScaleKernelInfo(kernel, 1.0/2.0, NoValue);
1502             break;
1503           case 17:
1504             kernel=ParseKernelArray("3: 1,-2,1  -2,4,-2  -1,-2,1");
1505             if (kernel == (KernelInfo *) NULL)
1506               return(kernel);
1507             kernel->type = type;
1508             ScaleKernelInfo(kernel, 1.0/6.0, NoValue);
1509             break;
1510           case 18:
1511             kernel=ParseKernelArray("3: -2,1,-2  1,4,1  -2,1,-2");
1512             if (kernel == (KernelInfo *) NULL)
1513               return(kernel);
1514             kernel->type = type;
1515             ScaleKernelInfo(kernel, 1.0/6.0, NoValue);
1516             break;
1517           case 19:
1518             kernel=ParseKernelArray("3: 1,1,1  1,1,1  1,1,1");
1519             if (kernel == (KernelInfo *) NULL)
1520               return(kernel);
1521             kernel->type = type;
1522             ScaleKernelInfo(kernel, 1.0/3.0, NoValue);
1523             break;
1524         }
1525         if ( fabs(args->sigma) >= MagickEpsilon )
1526           /* Rotate by correctly supplied 'angle' */
1527           RotateKernelInfo(kernel, args->sigma);
1528         else if ( args->rho > 30.0 || args->rho < -30.0 )
1529           /* Rotate by out of bounds 'type' */
1530           RotateKernelInfo(kernel, args->rho);
1531         break;
1532       }
1533 
1534     /*
1535       Boolean or Shaped Kernels
1536     */
1537     case DiamondKernel:
1538       {
1539         if (args->rho < 1.0)
1540           kernel->width = kernel->height = 3;  /* default radius = 1 */
1541         else
1542           kernel->width = kernel->height = ((size_t)args->rho)*2+1;
1543         kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1544 
1545         kernel->values=(MagickRealType *) MagickAssumeAligned(
1546           AcquireAlignedMemory(kernel->width,kernel->height*
1547           sizeof(*kernel->values)));
1548         if (kernel->values == (MagickRealType *) NULL)
1549           return(DestroyKernelInfo(kernel));
1550 
1551         /* set all kernel values within diamond area to scale given */
1552         for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1553           for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1554             if ( (labs((long) u)+labs((long) v)) <= (long) kernel->x)
1555               kernel->positive_range += kernel->values[i] = args->sigma;
1556             else
1557               kernel->values[i] = nan;
1558         kernel->minimum = kernel->maximum = args->sigma;   /* a flat shape */
1559         break;
1560       }
1561     case SquareKernel:
1562     case RectangleKernel:
1563       { double
1564           scale;
1565         if ( type == SquareKernel )
1566           {
1567             if (args->rho < 1.0)
1568               kernel->width = kernel->height = 3;  /* default radius = 1 */
1569             else
1570               kernel->width = kernel->height = (size_t) (2*args->rho+1);
1571             kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1572             scale = args->sigma;
1573           }
1574         else {
1575             /* NOTE: user defaults set in "AcquireKernelInfo()" */
1576             if ( args->rho < 1.0 || args->sigma < 1.0 )
1577               return(DestroyKernelInfo(kernel));    /* invalid args given */
1578             kernel->width = (size_t)args->rho;
1579             kernel->height = (size_t)args->sigma;
1580             if ( args->xi  < 0.0 || args->xi  > (double)kernel->width ||
1581                  args->psi < 0.0 || args->psi > (double)kernel->height )
1582               return(DestroyKernelInfo(kernel));    /* invalid args given */
1583             kernel->x = (ssize_t) args->xi;
1584             kernel->y = (ssize_t) args->psi;
1585             scale = 1.0;
1586           }
1587         kernel->values=(MagickRealType *) MagickAssumeAligned(
1588           AcquireAlignedMemory(kernel->width,kernel->height*
1589           sizeof(*kernel->values)));
1590         if (kernel->values == (MagickRealType *) NULL)
1591           return(DestroyKernelInfo(kernel));
1592 
1593         /* set all kernel values to scale given */
1594         u=(ssize_t) (kernel->width*kernel->height);
1595         for ( i=0; i < u; i++)
1596             kernel->values[i] = scale;
1597         kernel->minimum = kernel->maximum = scale;   /* a flat shape */
1598         kernel->positive_range = scale*u;
1599         break;
1600       }
1601       case OctagonKernel:
1602         {
1603           if (args->rho < 1.0)
1604             kernel->width = kernel->height = 5;  /* default radius = 2 */
1605           else
1606             kernel->width = kernel->height = ((size_t)args->rho)*2+1;
1607           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1608 
1609           kernel->values=(MagickRealType *) MagickAssumeAligned(
1610             AcquireAlignedMemory(kernel->width,kernel->height*
1611             sizeof(*kernel->values)));
1612           if (kernel->values == (MagickRealType *) NULL)
1613             return(DestroyKernelInfo(kernel));
1614 
1615           for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1616             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1617               if ( (labs((long) u)+labs((long) v)) <=
1618                         ((long)kernel->x + (long)(kernel->x/2)) )
1619                 kernel->positive_range += kernel->values[i] = args->sigma;
1620               else
1621                 kernel->values[i] = nan;
1622           kernel->minimum = kernel->maximum = args->sigma;  /* a flat shape */
1623           break;
1624         }
1625       case DiskKernel:
1626         {
1627           ssize_t
1628             limit = (ssize_t)(args->rho*args->rho);
1629 
1630           if (args->rho < 0.4)           /* default radius approx 4.3 */
1631             kernel->width = kernel->height = 9L, limit = 18L;
1632           else
1633             kernel->width = kernel->height = (size_t)fabs(args->rho)*2+1;
1634           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1635 
1636           kernel->values=(MagickRealType *) MagickAssumeAligned(
1637             AcquireAlignedMemory(kernel->width,kernel->height*
1638             sizeof(*kernel->values)));
1639           if (kernel->values == (MagickRealType *) NULL)
1640             return(DestroyKernelInfo(kernel));
1641 
1642           for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1643             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1644               if ((u*u+v*v) <= limit)
1645                 kernel->positive_range += kernel->values[i] = args->sigma;
1646               else
1647                 kernel->values[i] = nan;
1648           kernel->minimum = kernel->maximum = args->sigma;   /* a flat shape */
1649           break;
1650         }
1651       case PlusKernel:
1652         {
1653           if (args->rho < 1.0)
1654             kernel->width = kernel->height = 5;  /* default radius 2 */
1655           else
1656             kernel->width = kernel->height = ((size_t)args->rho)*2+1;
1657           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1658 
1659           kernel->values=(MagickRealType *) MagickAssumeAligned(
1660             AcquireAlignedMemory(kernel->width,kernel->height*
1661             sizeof(*kernel->values)));
1662           if (kernel->values == (MagickRealType *) NULL)
1663             return(DestroyKernelInfo(kernel));
1664 
1665           /* set all kernel values along axises to given scale */
1666           for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1667             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1668               kernel->values[i] = (u == 0 || v == 0) ? args->sigma : nan;
1669           kernel->minimum = kernel->maximum = args->sigma;   /* a flat shape */
1670           kernel->positive_range = args->sigma*(kernel->width*2.0 - 1.0);
1671           break;
1672         }
1673       case CrossKernel:
1674         {
1675           if (args->rho < 1.0)
1676             kernel->width = kernel->height = 5;  /* default radius 2 */
1677           else
1678             kernel->width = kernel->height = ((size_t)args->rho)*2+1;
1679           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1680 
1681           kernel->values=(MagickRealType *) MagickAssumeAligned(
1682             AcquireAlignedMemory(kernel->width,kernel->height*
1683             sizeof(*kernel->values)));
1684           if (kernel->values == (MagickRealType *) NULL)
1685             return(DestroyKernelInfo(kernel));
1686 
1687           /* set all kernel values along axises to given scale */
1688           for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
1689             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1690               kernel->values[i] = (u == v || u == -v) ? args->sigma : nan;
1691           kernel->minimum = kernel->maximum = args->sigma;   /* a flat shape */
1692           kernel->positive_range = args->sigma*(kernel->width*2.0 - 1.0);
1693           break;
1694         }
1695       /*
1696         HitAndMiss Kernels
1697       */
1698       case RingKernel:
1699       case PeaksKernel:
1700         {
1701           ssize_t
1702             limit1,
1703             limit2,
1704             scale;
1705 
1706           if (args->rho < args->sigma)
1707             {
1708               kernel->width = ((size_t)args->sigma)*2+1;
1709               limit1 = (ssize_t)(args->rho*args->rho);
1710               limit2 = (ssize_t)(args->sigma*args->sigma);
1711             }
1712           else
1713             {
1714               kernel->width = ((size_t)args->rho)*2+1;
1715               limit1 = (ssize_t)(args->sigma*args->sigma);
1716               limit2 = (ssize_t)(args->rho*args->rho);
1717             }
1718           if ( limit2 <= 0 )
1719             kernel->width = 7L, limit1 = 7L, limit2 = 11L;
1720 
1721           kernel->height = kernel->width;
1722           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
1723           kernel->values=(MagickRealType *) MagickAssumeAligned(
1724             AcquireAlignedMemory(kernel->width,kernel->height*
1725             sizeof(*kernel->values)));
1726           if (kernel->values == (MagickRealType *) NULL)
1727             return(DestroyKernelInfo(kernel));
1728 
1729           /* set a ring of points of 'scale' ( 0.0 for PeaksKernel ) */
1730           scale = (ssize_t) (( type == PeaksKernel) ? 0.0 : args->xi);
1731           for ( i=0, v= -kernel->y; v <= (ssize_t)kernel->y; v++)
1732             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
1733               { ssize_t radius=u*u+v*v;
1734                 if (limit1 < radius && radius <= limit2)
1735                   kernel->positive_range += kernel->values[i] = (double) scale;
1736                 else
1737                   kernel->values[i] = nan;
1738               }
1739           kernel->minimum = kernel->maximum = (double) scale;
1740           if ( type == PeaksKernel ) {
1741             /* set the central point in the middle */
1742             kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
1743             kernel->positive_range = 1.0;
1744             kernel->maximum = 1.0;
1745           }
1746           break;
1747         }
1748       case EdgesKernel:
1749         {
1750           kernel=AcquireKernelInfo("ThinSE:482",exception);
1751           if (kernel == (KernelInfo *) NULL)
1752             return(kernel);
1753           kernel->type = type;
1754           ExpandMirrorKernelInfo(kernel); /* mirror expansion of kernels */
1755           break;
1756         }
1757       case CornersKernel:
1758         {
1759           kernel=AcquireKernelInfo("ThinSE:87",exception);
1760           if (kernel == (KernelInfo *) NULL)
1761             return(kernel);
1762           kernel->type = type;
1763           ExpandRotateKernelInfo(kernel, 90.0); /* Expand 90 degree rotations */
1764           break;
1765         }
1766       case DiagonalsKernel:
1767         {
1768           switch ( (int) args->rho ) {
1769             case 0:
1770             default:
1771               { KernelInfo
1772                   *new_kernel;
1773                 kernel=ParseKernelArray("3: 0,0,0  0,-,1  1,1,-");
1774                 if (kernel == (KernelInfo *) NULL)
1775                   return(kernel);
1776                 kernel->type = type;
1777                 new_kernel=ParseKernelArray("3: 0,0,1  0,-,1  0,1,-");
1778                 if (new_kernel == (KernelInfo *) NULL)
1779                   return(DestroyKernelInfo(kernel));
1780                 new_kernel->type = type;
1781                 LastKernelInfo(kernel)->next = new_kernel;
1782                 ExpandMirrorKernelInfo(kernel);
1783                 return(kernel);
1784               }
1785             case 1:
1786               kernel=ParseKernelArray("3: 0,0,0  0,-,1  1,1,-");
1787               break;
1788             case 2:
1789               kernel=ParseKernelArray("3: 0,0,1  0,-,1  0,1,-");
1790               break;
1791           }
1792           if (kernel == (KernelInfo *) NULL)
1793             return(kernel);
1794           kernel->type = type;
1795           RotateKernelInfo(kernel, args->sigma);
1796           break;
1797         }
1798       case LineEndsKernel:
1799         { /* Kernels for finding the end of thin lines */
1800           switch ( (int) args->rho ) {
1801             case 0:
1802             default:
1803               /* set of kernels to find all end of lines */
1804               return(AcquireKernelInfo("LineEnds:1>;LineEnds:2>",exception));
1805             case 1:
1806               /* kernel for 4-connected line ends - no rotation */
1807               kernel=ParseKernelArray("3: 0,0,-  0,1,1  0,0,-");
1808               break;
1809           case 2:
1810               /* kernel to add for 8-connected lines - no rotation */
1811               kernel=ParseKernelArray("3: 0,0,0  0,1,0  0,0,1");
1812               break;
1813           case 3:
1814               /* kernel to add for orthogonal line ends - does not find corners */
1815               kernel=ParseKernelArray("3: 0,0,0  0,1,1  0,0,0");
1816               break;
1817           case 4:
1818               /* traditional line end - fails on last T end */
1819               kernel=ParseKernelArray("3: 0,0,0  0,1,-  0,0,-");
1820               break;
1821           }
1822           if (kernel == (KernelInfo *) NULL)
1823             return(kernel);
1824           kernel->type = type;
1825           RotateKernelInfo(kernel, args->sigma);
1826           break;
1827         }
1828       case LineJunctionsKernel:
1829         { /* kernels for finding the junctions of multiple lines */
1830           switch ( (int) args->rho ) {
1831             case 0:
1832             default:
1833               /* set of kernels to find all line junctions */
1834               return(AcquireKernelInfo("LineJunctions:1@;LineJunctions:2>",exception));
1835             case 1:
1836               /* Y Junction */
1837               kernel=ParseKernelArray("3: 1,-,1  -,1,-  -,1,-");
1838               break;
1839             case 2:
1840               /* Diagonal T Junctions */
1841               kernel=ParseKernelArray("3: 1,-,-  -,1,-  1,-,1");
1842               break;
1843             case 3:
1844               /* Orthogonal T Junctions */
1845               kernel=ParseKernelArray("3: -,-,-  1,1,1  -,1,-");
1846               break;
1847             case 4:
1848               /* Diagonal X Junctions */
1849               kernel=ParseKernelArray("3: 1,-,1  -,1,-  1,-,1");
1850               break;
1851             case 5:
1852               /* Orthogonal X Junctions - minimal diamond kernel */
1853               kernel=ParseKernelArray("3: -,1,-  1,1,1  -,1,-");
1854               break;
1855           }
1856           if (kernel == (KernelInfo *) NULL)
1857             return(kernel);
1858           kernel->type = type;
1859           RotateKernelInfo(kernel, args->sigma);
1860           break;
1861         }
1862       case RidgesKernel:
1863         { /* Ridges - Ridge finding kernels */
1864           KernelInfo
1865             *new_kernel;
1866           switch ( (int) args->rho ) {
1867             case 1:
1868             default:
1869               kernel=ParseKernelArray("3x1:0,1,0");
1870               if (kernel == (KernelInfo *) NULL)
1871                 return(kernel);
1872               kernel->type = type;
1873               ExpandRotateKernelInfo(kernel, 90.0); /* 2 rotated kernels (symmetrical) */
1874               break;
1875             case 2:
1876               kernel=ParseKernelArray("4x1:0,1,1,0");
1877               if (kernel == (KernelInfo *) NULL)
1878                 return(kernel);
1879               kernel->type = type;
1880               ExpandRotateKernelInfo(kernel, 90.0); /* 4 rotated kernels */
1881 
1882               /* Kernels to find a stepped 'thick' line, 4 rotates + mirrors */
1883               /* Unfortunatally we can not yet rotate a non-square kernel */
1884               /* But then we can't flip a non-symetrical kernel either */
1885               new_kernel=ParseKernelArray("4x3+1+1:0,1,1,- -,1,1,- -,1,1,0");
1886               if (new_kernel == (KernelInfo *) NULL)
1887                 return(DestroyKernelInfo(kernel));
1888               new_kernel->type = type;
1889               LastKernelInfo(kernel)->next = new_kernel;
1890               new_kernel=ParseKernelArray("4x3+2+1:0,1,1,- -,1,1,- -,1,1,0");
1891               if (new_kernel == (KernelInfo *) NULL)
1892                 return(DestroyKernelInfo(kernel));
1893               new_kernel->type = type;
1894               LastKernelInfo(kernel)->next = new_kernel;
1895               new_kernel=ParseKernelArray("4x3+1+1:-,1,1,0 -,1,1,- 0,1,1,-");
1896               if (new_kernel == (KernelInfo *) NULL)
1897                 return(DestroyKernelInfo(kernel));
1898               new_kernel->type = type;
1899               LastKernelInfo(kernel)->next = new_kernel;
1900               new_kernel=ParseKernelArray("4x3+2+1:-,1,1,0 -,1,1,- 0,1,1,-");
1901               if (new_kernel == (KernelInfo *) NULL)
1902                 return(DestroyKernelInfo(kernel));
1903               new_kernel->type = type;
1904               LastKernelInfo(kernel)->next = new_kernel;
1905               new_kernel=ParseKernelArray("3x4+1+1:0,-,- 1,1,1 1,1,1 -,-,0");
1906               if (new_kernel == (KernelInfo *) NULL)
1907                 return(DestroyKernelInfo(kernel));
1908               new_kernel->type = type;
1909               LastKernelInfo(kernel)->next = new_kernel;
1910               new_kernel=ParseKernelArray("3x4+1+2:0,-,- 1,1,1 1,1,1 -,-,0");
1911               if (new_kernel == (KernelInfo *) NULL)
1912                 return(DestroyKernelInfo(kernel));
1913               new_kernel->type = type;
1914               LastKernelInfo(kernel)->next = new_kernel;
1915               new_kernel=ParseKernelArray("3x4+1+1:-,-,0 1,1,1 1,1,1 0,-,-");
1916               if (new_kernel == (KernelInfo *) NULL)
1917                 return(DestroyKernelInfo(kernel));
1918               new_kernel->type = type;
1919               LastKernelInfo(kernel)->next = new_kernel;
1920               new_kernel=ParseKernelArray("3x4+1+2:-,-,0 1,1,1 1,1,1 0,-,-");
1921               if (new_kernel == (KernelInfo *) NULL)
1922                 return(DestroyKernelInfo(kernel));
1923               new_kernel->type = type;
1924               LastKernelInfo(kernel)->next = new_kernel;
1925               break;
1926           }
1927           break;
1928         }
1929       case ConvexHullKernel:
1930         {
1931           KernelInfo
1932             *new_kernel;
1933           /* first set of 8 kernels */
1934           kernel=ParseKernelArray("3: 1,1,-  1,0,-  1,-,0");
1935           if (kernel == (KernelInfo *) NULL)
1936             return(kernel);
1937           kernel->type = type;
1938           ExpandRotateKernelInfo(kernel, 90.0);
1939           /* append the mirror versions too - no flip function yet */
1940           new_kernel=ParseKernelArray("3: 1,1,1  1,0,-  -,-,0");
1941           if (new_kernel == (KernelInfo *) NULL)
1942             return(DestroyKernelInfo(kernel));
1943           new_kernel->type = type;
1944           ExpandRotateKernelInfo(new_kernel, 90.0);
1945           LastKernelInfo(kernel)->next = new_kernel;
1946           break;
1947         }
1948       case SkeletonKernel:
1949         {
1950           switch ( (int) args->rho ) {
1951             case 1:
1952             default:
1953               /* Traditional Skeleton...
1954               ** A cyclically rotated single kernel
1955               */
1956               kernel=AcquireKernelInfo("ThinSE:482",exception);
1957               if (kernel == (KernelInfo *) NULL)
1958                 return(kernel);
1959               kernel->type = type;
1960               ExpandRotateKernelInfo(kernel, 45.0); /* 8 rotations */
1961               break;
1962             case 2:
1963               /* HIPR Variation of the cyclic skeleton
1964               ** Corners of the traditional method made more forgiving,
1965               ** but the retain the same cyclic order.
1966               */
1967               kernel=AcquireKernelInfo("ThinSE:482; ThinSE:87x90;",exception);
1968               if (kernel == (KernelInfo *) NULL)
1969                 return(kernel);
1970               if (kernel->next == (KernelInfo *) NULL)
1971                 return(DestroyKernelInfo(kernel));
1972               kernel->type = type;
1973               kernel->next->type = type;
1974               ExpandRotateKernelInfo(kernel, 90.0); /* 4 rotations of the 2 kernels */
1975               break;
1976             case 3:
1977               /* Dan Bloomberg Skeleton, from his paper on 3x3 thinning SE's
1978               ** "Connectivity-Preserving Morphological Image Thransformations"
1979               ** by Dan S. Bloomberg, available on Leptonica, Selected Papers,
1980               **   http://www.leptonica.com/papers/conn.pdf
1981               */
1982               kernel=AcquireKernelInfo("ThinSE:41; ThinSE:42; ThinSE:43",
1983                 exception);
1984               if (kernel == (KernelInfo *) NULL)
1985                 return(kernel);
1986               kernel->type = type;
1987               kernel->next->type = type;
1988               kernel->next->next->type = type;
1989               ExpandMirrorKernelInfo(kernel); /* 12 kernels total */
1990               break;
1991            }
1992           break;
1993         }
1994       case ThinSEKernel:
1995         { /* Special kernels for general thinning, while preserving connections
1996           ** "Connectivity-Preserving Morphological Image Thransformations"
1997           ** by Dan S. Bloomberg, available on Leptonica, Selected Papers,
1998           **   http://www.leptonica.com/papers/conn.pdf
1999           ** And
2000           **   http://tpgit.github.com/Leptonica/ccthin_8c_source.html
2001           **
2002           ** Note kernels do not specify the origin pixel, allowing them
2003           ** to be used for both thickening and thinning operations.
2004           */
2005           switch ( (int) args->rho ) {
2006             /* SE for 4-connected thinning */
2007             case 41: /* SE_4_1 */
2008               kernel=ParseKernelArray("3: -,-,1  0,-,1  -,-,1");
2009               break;
2010             case 42: /* SE_4_2 */
2011               kernel=ParseKernelArray("3: -,-,1  0,-,1  -,0,-");
2012               break;
2013             case 43: /* SE_4_3 */
2014               kernel=ParseKernelArray("3: -,0,-  0,-,1  -,-,1");
2015               break;
2016             case 44: /* SE_4_4 */
2017               kernel=ParseKernelArray("3: -,0,-  0,-,1  -,0,-");
2018               break;
2019             case 45: /* SE_4_5 */
2020               kernel=ParseKernelArray("3: -,0,1  0,-,1  -,0,-");
2021               break;
2022             case 46: /* SE_4_6 */
2023               kernel=ParseKernelArray("3: -,0,-  0,-,1  -,0,1");
2024               break;
2025             case 47: /* SE_4_7 */
2026               kernel=ParseKernelArray("3: -,1,1  0,-,1  -,0,-");
2027               break;
2028             case 48: /* SE_4_8 */
2029               kernel=ParseKernelArray("3: -,-,1  0,-,1  0,-,1");
2030               break;
2031             case 49: /* SE_4_9 */
2032               kernel=ParseKernelArray("3: 0,-,1  0,-,1  -,-,1");
2033               break;
2034             /* SE for 8-connected thinning - negatives of the above */
2035             case 81: /* SE_8_0 */
2036               kernel=ParseKernelArray("3: -,1,-  0,-,1  -,1,-");
2037               break;
2038             case 82: /* SE_8_2 */
2039               kernel=ParseKernelArray("3: -,1,-  0,-,1  0,-,-");
2040               break;
2041             case 83: /* SE_8_3 */
2042               kernel=ParseKernelArray("3: 0,-,-  0,-,1  -,1,-");
2043               break;
2044             case 84: /* SE_8_4 */
2045               kernel=ParseKernelArray("3: 0,-,-  0,-,1  0,-,-");
2046               break;
2047             case 85: /* SE_8_5 */
2048               kernel=ParseKernelArray("3: 0,-,1  0,-,1  0,-,-");
2049               break;
2050             case 86: /* SE_8_6 */
2051               kernel=ParseKernelArray("3: 0,-,-  0,-,1  0,-,1");
2052               break;
2053             case 87: /* SE_8_7 */
2054               kernel=ParseKernelArray("3: -,1,-  0,-,1  0,0,-");
2055               break;
2056             case 88: /* SE_8_8 */
2057               kernel=ParseKernelArray("3: -,1,-  0,-,1  0,1,-");
2058               break;
2059             case 89: /* SE_8_9 */
2060               kernel=ParseKernelArray("3: 0,1,-  0,-,1  -,1,-");
2061               break;
2062             /* Special combined SE kernels */
2063             case 423: /* SE_4_2 , SE_4_3 Combined Kernel */
2064               kernel=ParseKernelArray("3: -,-,1  0,-,-  -,0,-");
2065               break;
2066             case 823: /* SE_8_2 , SE_8_3 Combined Kernel */
2067               kernel=ParseKernelArray("3: -,1,-  -,-,1  0,-,-");
2068               break;
2069             case 481: /* SE_48_1 - General Connected Corner Kernel */
2070               kernel=ParseKernelArray("3: -,1,1  0,-,1  0,0,-");
2071               break;
2072             default:
2073             case 482: /* SE_48_2 - General Edge Kernel */
2074               kernel=ParseKernelArray("3: 0,-,1  0,-,1  0,-,1");
2075               break;
2076           }
2077           if (kernel == (KernelInfo *) NULL)
2078             return(kernel);
2079           kernel->type = type;
2080           RotateKernelInfo(kernel, args->sigma);
2081           break;
2082         }
2083       /*
2084         Distance Measuring Kernels
2085       */
2086       case ChebyshevKernel:
2087         {
2088           if (args->rho < 1.0)
2089             kernel->width = kernel->height = 3;  /* default radius = 1 */
2090           else
2091             kernel->width = kernel->height = ((size_t)args->rho)*2+1;
2092           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
2093 
2094           kernel->values=(MagickRealType *) MagickAssumeAligned(
2095             AcquireAlignedMemory(kernel->width,kernel->height*
2096             sizeof(*kernel->values)));
2097           if (kernel->values == (MagickRealType *) NULL)
2098             return(DestroyKernelInfo(kernel));
2099 
2100           for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
2101             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
2102               kernel->positive_range += ( kernel->values[i] =
2103                   args->sigma*MagickMax(fabs((double)u),fabs((double)v)) );
2104           kernel->maximum = kernel->values[0];
2105           break;
2106         }
2107       case ManhattanKernel:
2108         {
2109           if (args->rho < 1.0)
2110             kernel->width = kernel->height = 3;  /* default radius = 1 */
2111           else
2112             kernel->width = kernel->height = ((size_t)args->rho)*2+1;
2113           kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
2114 
2115           kernel->values=(MagickRealType *) MagickAssumeAligned(
2116             AcquireAlignedMemory(kernel->width,kernel->height*
2117             sizeof(*kernel->values)));
2118           if (kernel->values == (MagickRealType *) NULL)
2119             return(DestroyKernelInfo(kernel));
2120 
2121           for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
2122             for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
2123               kernel->positive_range += ( kernel->values[i] =
2124                   args->sigma*(labs((long) u)+labs((long) v)) );
2125           kernel->maximum = kernel->values[0];
2126           break;
2127         }
2128       case OctagonalKernel:
2129       {
2130         if (args->rho < 2.0)
2131           kernel->width = kernel->height = 5;  /* default/minimum radius = 2 */
2132         else
2133           kernel->width = kernel->height = ((size_t)args->rho)*2+1;
2134         kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
2135 
2136         kernel->values=(MagickRealType *) MagickAssumeAligned(
2137           AcquireAlignedMemory(kernel->width,kernel->height*
2138           sizeof(*kernel->values)));
2139         if (kernel->values == (MagickRealType *) NULL)
2140           return(DestroyKernelInfo(kernel));
2141 
2142         for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
2143           for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
2144             {
2145               double
2146                 r1 = MagickMax(fabs((double)u),fabs((double)v)),
2147                 r2 = floor((double)(labs((long)u)+labs((long)v)+1)/1.5);
2148               kernel->positive_range += kernel->values[i] =
2149                         args->sigma*MagickMax(r1,r2);
2150             }
2151         kernel->maximum = kernel->values[0];
2152         break;
2153       }
2154     case EuclideanKernel:
2155       {
2156         if (args->rho < 1.0)
2157           kernel->width = kernel->height = 3;  /* default radius = 1 */
2158         else
2159           kernel->width = kernel->height = ((size_t)args->rho)*2+1;
2160         kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
2161 
2162         kernel->values=(MagickRealType *) MagickAssumeAligned(
2163           AcquireAlignedMemory(kernel->width,kernel->height*
2164           sizeof(*kernel->values)));
2165         if (kernel->values == (MagickRealType *) NULL)
2166           return(DestroyKernelInfo(kernel));
2167 
2168         for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
2169           for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
2170             kernel->positive_range += ( kernel->values[i] =
2171               args->sigma*sqrt((double)(u*u+v*v)) );
2172         kernel->maximum = kernel->values[0];
2173         break;
2174       }
2175     default:
2176       {
2177         /* No-Op Kernel - Basically just a single pixel on its own */
2178         kernel=ParseKernelArray("1:1");
2179         if (kernel == (KernelInfo *) NULL)
2180           return(kernel);
2181         kernel->type = UndefinedKernel;
2182         break;
2183       }
2184       break;
2185   }
2186   return(kernel);
2187 }
2188 
2189 /*
2190 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2191 %                                                                             %
2192 %                                                                             %
2193 %                                                                             %
2194 %     C l o n e K e r n e l I n f o                                           %
2195 %                                                                             %
2196 %                                                                             %
2197 %                                                                             %
2198 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2199 %
2200 %  CloneKernelInfo() creates a new clone of the given Kernel List so that its
2201 %  can be modified without effecting the original.  The cloned kernel should
2202 %  be destroyed using DestoryKernelInfo() when no longer needed.
2203 %
2204 %  The format of the CloneKernelInfo method is:
2205 %
2206 %      KernelInfo *CloneKernelInfo(const KernelInfo *kernel)
2207 %
2208 %  A description of each parameter follows:
2209 %
2210 %    o kernel: the Morphology/Convolution kernel to be cloned
2211 %
2212 */
CloneKernelInfo(const KernelInfo * kernel)2213 MagickExport KernelInfo *CloneKernelInfo(const KernelInfo *kernel)
2214 {
2215   register ssize_t
2216     i;
2217 
2218   KernelInfo
2219     *new_kernel;
2220 
2221   assert(kernel != (KernelInfo *) NULL);
2222   new_kernel=(KernelInfo *) AcquireMagickMemory(sizeof(*kernel));
2223   if (new_kernel == (KernelInfo *) NULL)
2224     return(new_kernel);
2225   *new_kernel=(*kernel); /* copy values in structure */
2226 
2227   /* replace the values with a copy of the values */
2228   new_kernel->values=(MagickRealType *) MagickAssumeAligned(
2229     AcquireAlignedMemory(kernel->width,kernel->height*sizeof(*kernel->values)));
2230   if (new_kernel->values == (MagickRealType *) NULL)
2231     return(DestroyKernelInfo(new_kernel));
2232   for (i=0; i < (ssize_t) (kernel->width*kernel->height); i++)
2233     new_kernel->values[i]=kernel->values[i];
2234 
2235   /* Also clone the next kernel in the kernel list */
2236   if ( kernel->next != (KernelInfo *) NULL ) {
2237     new_kernel->next = CloneKernelInfo(kernel->next);
2238     if ( new_kernel->next == (KernelInfo *) NULL )
2239       return(DestroyKernelInfo(new_kernel));
2240   }
2241 
2242   return(new_kernel);
2243 }
2244 
2245 /*
2246 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2247 %                                                                             %
2248 %                                                                             %
2249 %                                                                             %
2250 %     D e s t r o y K e r n e l I n f o                                       %
2251 %                                                                             %
2252 %                                                                             %
2253 %                                                                             %
2254 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2255 %
2256 %  DestroyKernelInfo() frees the memory used by a Convolution/Morphology
2257 %  kernel.
2258 %
2259 %  The format of the DestroyKernelInfo method is:
2260 %
2261 %      KernelInfo *DestroyKernelInfo(KernelInfo *kernel)
2262 %
2263 %  A description of each parameter follows:
2264 %
2265 %    o kernel: the Morphology/Convolution kernel to be destroyed
2266 %
2267 */
DestroyKernelInfo(KernelInfo * kernel)2268 MagickExport KernelInfo *DestroyKernelInfo(KernelInfo *kernel)
2269 {
2270   assert(kernel != (KernelInfo *) NULL);
2271   if (kernel->next != (KernelInfo *) NULL)
2272     kernel->next=DestroyKernelInfo(kernel->next);
2273   kernel->values=(MagickRealType *) RelinquishAlignedMemory(kernel->values);
2274   kernel=(KernelInfo *) RelinquishMagickMemory(kernel);
2275   return(kernel);
2276 }
2277 
2278 /*
2279 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2280 %                                                                             %
2281 %                                                                             %
2282 %                                                                             %
2283 +     E x p a n d M i r r o r K e r n e l I n f o                             %
2284 %                                                                             %
2285 %                                                                             %
2286 %                                                                             %
2287 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2288 %
2289 %  ExpandMirrorKernelInfo() takes a single kernel, and expands it into a
2290 %  sequence of 90-degree rotated kernels but providing a reflected 180
2291 %  rotatation, before the -/+ 90-degree rotations.
2292 %
2293 %  This special rotation order produces a better, more symetrical thinning of
2294 %  objects.
2295 %
2296 %  The format of the ExpandMirrorKernelInfo method is:
2297 %
2298 %      void ExpandMirrorKernelInfo(KernelInfo *kernel)
2299 %
2300 %  A description of each parameter follows:
2301 %
2302 %    o kernel: the Morphology/Convolution kernel
2303 %
2304 % This function is only internel to this module, as it is not finalized,
2305 % especially with regard to non-orthogonal angles, and rotation of larger
2306 % 2D kernels.
2307 */
2308 
2309 #if 0
2310 static void FlopKernelInfo(KernelInfo *kernel)
2311     { /* Do a Flop by reversing each row. */
2312       size_t
2313         y;
2314       register ssize_t
2315         x,r;
2316       register double
2317         *k,t;
2318 
2319       for ( y=0, k=kernel->values; y < kernel->height; y++, k+=kernel->width)
2320         for ( x=0, r=kernel->width-1; x<kernel->width/2; x++, r--)
2321           t=k[x],  k[x]=k[r],  k[r]=t;
2322 
2323       kernel->x = kernel->width - kernel->x - 1;
2324       angle = fmod(angle+180.0, 360.0);
2325     }
2326 #endif
2327 
ExpandMirrorKernelInfo(KernelInfo * kernel)2328 static void ExpandMirrorKernelInfo(KernelInfo *kernel)
2329 {
2330   KernelInfo
2331     *clone,
2332     *last;
2333 
2334   last = kernel;
2335 
2336   clone = CloneKernelInfo(last);
2337   if (clone == (KernelInfo *) NULL)
2338     return;
2339   RotateKernelInfo(clone, 180);   /* flip */
2340   LastKernelInfo(last)->next = clone;
2341   last = clone;
2342 
2343   clone = CloneKernelInfo(last);
2344   if (clone == (KernelInfo *) NULL)
2345     return;
2346   RotateKernelInfo(clone, 90);   /* transpose */
2347   LastKernelInfo(last)->next = clone;
2348   last = clone;
2349 
2350   clone = CloneKernelInfo(last);
2351   if (clone == (KernelInfo *) NULL)
2352     return;
2353   RotateKernelInfo(clone, 180);  /* flop */
2354   LastKernelInfo(last)->next = clone;
2355 
2356   return;
2357 }
2358 
2359 /*
2360 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2361 %                                                                             %
2362 %                                                                             %
2363 %                                                                             %
2364 +     E x p a n d R o t a t e K e r n e l I n f o                             %
2365 %                                                                             %
2366 %                                                                             %
2367 %                                                                             %
2368 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2369 %
2370 %  ExpandRotateKernelInfo() takes a kernel list, and expands it by rotating
2371 %  incrementally by the angle given, until the kernel repeats.
2372 %
2373 %  WARNING: 45 degree rotations only works for 3x3 kernels.
2374 %  While 90 degree roatations only works for linear and square kernels
2375 %
2376 %  The format of the ExpandRotateKernelInfo method is:
2377 %
2378 %      void ExpandRotateKernelInfo(KernelInfo *kernel, double angle)
2379 %
2380 %  A description of each parameter follows:
2381 %
2382 %    o kernel: the Morphology/Convolution kernel
2383 %
2384 %    o angle: angle to rotate in degrees
2385 %
2386 % This function is only internel to this module, as it is not finalized,
2387 % especially with regard to non-orthogonal angles, and rotation of larger
2388 % 2D kernels.
2389 */
2390 
2391 /* Internal Routine - Return true if two kernels are the same */
SameKernelInfo(const KernelInfo * kernel1,const KernelInfo * kernel2)2392 static MagickBooleanType SameKernelInfo(const KernelInfo *kernel1,
2393      const KernelInfo *kernel2)
2394 {
2395   register size_t
2396     i;
2397 
2398   /* check size and origin location */
2399   if (    kernel1->width != kernel2->width
2400        || kernel1->height != kernel2->height
2401        || kernel1->x != kernel2->x
2402        || kernel1->y != kernel2->y )
2403     return MagickFalse;
2404 
2405   /* check actual kernel values */
2406   for (i=0; i < (kernel1->width*kernel1->height); i++) {
2407     /* Test for Nan equivalence */
2408     if ( IsNaN(kernel1->values[i]) && !IsNaN(kernel2->values[i]) )
2409       return MagickFalse;
2410     if ( IsNaN(kernel2->values[i]) && !IsNaN(kernel1->values[i]) )
2411       return MagickFalse;
2412     /* Test actual values are equivalent */
2413     if ( fabs(kernel1->values[i] - kernel2->values[i]) >= MagickEpsilon )
2414       return MagickFalse;
2415   }
2416 
2417   return MagickTrue;
2418 }
2419 
ExpandRotateKernelInfo(KernelInfo * kernel,const double angle)2420 static void ExpandRotateKernelInfo(KernelInfo *kernel, const double angle)
2421 {
2422   KernelInfo
2423     *clone_info,
2424     *last;
2425 
2426   last=kernel;
2427 DisableMSCWarning(4127)
2428   while (1) {
2429 RestoreMSCWarning
2430     clone_info=CloneKernelInfo(last);
2431     if (clone_info == (KernelInfo *) NULL)
2432       break;
2433     RotateKernelInfo(clone_info,angle);
2434     if (SameKernelInfo(kernel,clone_info) != MagickFalse)
2435       break;
2436     LastKernelInfo(last)->next=clone_info;
2437     last=clone_info;
2438   }
2439   if (clone_info != (KernelInfo *) NULL)
2440     clone_info=DestroyKernelInfo(clone_info);  /* kernel repeated - junk */
2441   return;
2442 }
2443 
2444 /*
2445 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2446 %                                                                             %
2447 %                                                                             %
2448 %                                                                             %
2449 +     C a l c M e t a K e r n a l I n f o                                     %
2450 %                                                                             %
2451 %                                                                             %
2452 %                                                                             %
2453 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2454 %
2455 %  CalcKernelMetaData() recalculate the KernelInfo meta-data of this kernel only,
2456 %  using the kernel values.  This should only ne used if it is not possible to
2457 %  calculate that meta-data in some easier way.
2458 %
2459 %  It is important that the meta-data is correct before ScaleKernelInfo() is
2460 %  used to perform kernel normalization.
2461 %
2462 %  The format of the CalcKernelMetaData method is:
2463 %
2464 %      void CalcKernelMetaData(KernelInfo *kernel, const double scale )
2465 %
2466 %  A description of each parameter follows:
2467 %
2468 %    o kernel: the Morphology/Convolution kernel to modify
2469 %
2470 %  WARNING: Minimum and Maximum values are assumed to include zero, even if
2471 %  zero is not part of the kernel (as in Gaussian Derived kernels). This
2472 %  however is not true for flat-shaped morphological kernels.
2473 %
2474 %  WARNING: Only the specific kernel pointed to is modified, not a list of
2475 %  multiple kernels.
2476 %
2477 % This is an internal function and not expected to be useful outside this
2478 % module.  This could change however.
2479 */
CalcKernelMetaData(KernelInfo * kernel)2480 static void CalcKernelMetaData(KernelInfo *kernel)
2481 {
2482   register size_t
2483     i;
2484 
2485   kernel->minimum = kernel->maximum = 0.0;
2486   kernel->negative_range = kernel->positive_range = 0.0;
2487   for (i=0; i < (kernel->width*kernel->height); i++)
2488     {
2489       if ( fabs(kernel->values[i]) < MagickEpsilon )
2490         kernel->values[i] = 0.0;
2491       ( kernel->values[i] < 0)
2492           ?  ( kernel->negative_range += kernel->values[i] )
2493           :  ( kernel->positive_range += kernel->values[i] );
2494       Minimize(kernel->minimum, kernel->values[i]);
2495       Maximize(kernel->maximum, kernel->values[i]);
2496     }
2497 
2498   return;
2499 }
2500 
2501 /*
2502 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2503 %                                                                             %
2504 %                                                                             %
2505 %                                                                             %
2506 %     M o r p h o l o g y A p p l y                                           %
2507 %                                                                             %
2508 %                                                                             %
2509 %                                                                             %
2510 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2511 %
2512 %  MorphologyApply() applies a morphological method, multiple times using
2513 %  a list of multiple kernels.  This is the method that should be called by
2514 %  other 'operators' that internally use morphology operations as part of
2515 %  their processing.
2516 %
2517 %  It is basically equivalent to as MorphologyImage() (see below) but without
2518 %  any user controls.  This allows internel programs to use this method to
2519 %  perform a specific task without possible interference by any API user
2520 %  supplied settings.
2521 %
2522 %  It is MorphologyImage() task to extract any such user controls, and
2523 %  pass them to this function for processing.
2524 %
2525 %  More specifically all given kernels should already be scaled, normalised,
2526 %  and blended appropriatally before being parred to this routine. The
2527 %  appropriate bias, and compose (typically 'UndefinedComposeOp') given.
2528 %
2529 %  The format of the MorphologyApply method is:
2530 %
2531 %      Image *MorphologyApply(const Image *image,MorphologyMethod method,
2532 %        const ssize_t iterations,const KernelInfo *kernel,
2533 %        const CompositeMethod compose,const double bias,
2534 %        ExceptionInfo *exception)
2535 %
2536 %  A description of each parameter follows:
2537 %
2538 %    o image: the source image
2539 %
2540 %    o method: the morphology method to be applied.
2541 %
2542 %    o iterations: apply the operation this many times (or no change).
2543 %                  A value of -1 means loop until no change found.
2544 %                  How this is applied may depend on the morphology method.
2545 %                  Typically this is a value of 1.
2546 %
2547 %    o channel: the channel type.
2548 %
2549 %    o kernel: An array of double representing the morphology kernel.
2550 %
2551 %    o compose: How to handle or merge multi-kernel results.
2552 %          If 'UndefinedCompositeOp' use default for the Morphology method.
2553 %          If 'NoCompositeOp' force image to be re-iterated by each kernel.
2554 %          Otherwise merge the results using the compose method given.
2555 %
2556 %    o bias: Convolution Output Bias.
2557 %
2558 %    o exception: return any errors or warnings in this structure.
2559 %
2560 */
MorphologyPrimitive(const Image * image,Image * morphology_image,const MorphologyMethod method,const KernelInfo * kernel,const double bias,ExceptionInfo * exception)2561 static ssize_t MorphologyPrimitive(const Image *image,Image *morphology_image,
2562   const MorphologyMethod method,const KernelInfo *kernel,const double bias,
2563   ExceptionInfo *exception)
2564 {
2565 #define MorphologyTag  "Morphology/Image"
2566 
2567   CacheView
2568     *image_view,
2569     *morphology_view;
2570 
2571   OffsetInfo
2572     offset;
2573 
2574   register ssize_t
2575     j,
2576     y;
2577 
2578   size_t
2579     *changes,
2580     changed,
2581     width;
2582 
2583   MagickBooleanType
2584     status;
2585 
2586   MagickOffsetType
2587     progress;
2588 
2589   assert(image != (Image *) NULL);
2590   assert(image->signature == MagickCoreSignature);
2591   assert(morphology_image != (Image *) NULL);
2592   assert(morphology_image->signature == MagickCoreSignature);
2593   assert(kernel != (KernelInfo *) NULL);
2594   assert(kernel->signature == MagickCoreSignature);
2595   assert(exception != (ExceptionInfo *) NULL);
2596   assert(exception->signature == MagickCoreSignature);
2597   status=MagickTrue;
2598   progress=0;
2599   image_view=AcquireVirtualCacheView(image,exception);
2600   morphology_view=AcquireAuthenticCacheView(morphology_image,exception);
2601   width=image->columns+kernel->width-1;
2602   offset.x=0;
2603   offset.y=0;
2604   switch (method)
2605   {
2606     case ConvolveMorphology:
2607     case DilateMorphology:
2608     case DilateIntensityMorphology:
2609     case IterativeDistanceMorphology:
2610     {
2611       /*
2612         Kernel needs to used with reflection about origin.
2613       */
2614       offset.x=(ssize_t) kernel->width-kernel->x-1;
2615       offset.y=(ssize_t) kernel->height-kernel->y-1;
2616       break;
2617     }
2618     case ErodeMorphology:
2619     case ErodeIntensityMorphology:
2620     case HitAndMissMorphology:
2621     case ThinningMorphology:
2622     case ThickenMorphology:
2623     {
2624       offset.x=kernel->x;
2625       offset.y=kernel->y;
2626       break;
2627     }
2628     default:
2629     {
2630       assert("Not a Primitive Morphology Method" != (char *) NULL);
2631       break;
2632     }
2633   }
2634   changed=0;
2635   changes=(size_t *) AcquireQuantumMemory(GetOpenMPMaximumThreads(),
2636     sizeof(*changes));
2637   if (changes == (size_t *) NULL)
2638     ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
2639   for (j=0; j < (ssize_t) GetOpenMPMaximumThreads(); j++)
2640     changes[j]=0;
2641 
2642   if ((method == ConvolveMorphology) && (kernel->width == 1))
2643     {
2644       register ssize_t
2645         x;
2646 
2647       /*
2648         Special handling (for speed) of vertical (blur) kernels.  This performs
2649         its handling in columns rather than in rows.  This is only done
2650         for convolve as it is the only method that generates very large 1-D
2651         vertical kernels (such as a 'BlurKernel')
2652      */
2653 #if defined(MAGICKCORE_OPENMP_SUPPORT)
2654      #pragma omp parallel for schedule(static) shared(progress,status) \
2655        magick_number_threads(image,morphology_image,image->columns,1)
2656 #endif
2657       for (x=0; x < (ssize_t) image->columns; x++)
2658       {
2659         const int
2660           id = GetOpenMPThreadId();
2661 
2662         register const Quantum
2663           *magick_restrict p;
2664 
2665         register Quantum
2666           *magick_restrict q;
2667 
2668         register ssize_t
2669           r;
2670 
2671         ssize_t
2672           center;
2673 
2674         if (status == MagickFalse)
2675           continue;
2676         p=GetCacheViewVirtualPixels(image_view,x,-offset.y,1,image->rows+
2677           kernel->height-1,exception);
2678         q=GetCacheViewAuthenticPixels(morphology_view,x,0,1,
2679           morphology_image->rows,exception);
2680         if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
2681           {
2682             status=MagickFalse;
2683             continue;
2684           }
2685         center=(ssize_t) GetPixelChannels(image)*offset.y;
2686         for (r=0; r < (ssize_t) image->rows; r++)
2687         {
2688           register ssize_t
2689             i;
2690 
2691           for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
2692           {
2693             double
2694               alpha,
2695               gamma,
2696               pixel;
2697 
2698             PixelChannel
2699               channel;
2700 
2701             PixelTrait
2702               morphology_traits,
2703               traits;
2704 
2705             register const MagickRealType
2706               *magick_restrict k;
2707 
2708             register const Quantum
2709               *magick_restrict pixels;
2710 
2711             register ssize_t
2712               v;
2713 
2714             size_t
2715               count;
2716 
2717             channel=GetPixelChannelChannel(image,i);
2718             traits=GetPixelChannelTraits(image,channel);
2719             morphology_traits=GetPixelChannelTraits(morphology_image,channel);
2720             if ((traits == UndefinedPixelTrait) ||
2721                 (morphology_traits == UndefinedPixelTrait))
2722               continue;
2723             if ((traits & CopyPixelTrait) != 0)
2724               {
2725                 SetPixelChannel(morphology_image,channel,p[center+i],q);
2726                 continue;
2727               }
2728             k=(&kernel->values[kernel->height-1]);
2729             pixels=p;
2730             pixel=bias;
2731             gamma=0.0;
2732             count=0;
2733             if ((morphology_traits & BlendPixelTrait) == 0)
2734               for (v=0; v < (ssize_t) kernel->height; v++)
2735               {
2736                 if (!IsNaN(*k))
2737                   {
2738                     pixel+=(*k)*pixels[i];
2739                     gamma+=(*k);
2740                     count++;
2741                   }
2742                 k--;
2743                 pixels+=GetPixelChannels(image);
2744               }
2745             else
2746               for (v=0; v < (ssize_t) kernel->height; v++)
2747               {
2748                 if (!IsNaN(*k))
2749                   {
2750                     alpha=(double) (QuantumScale*GetPixelAlpha(image,pixels));
2751                     pixel+=alpha*(*k)*pixels[i];
2752                     gamma+=alpha*(*k);
2753                     count++;
2754                   }
2755                 k--;
2756                 pixels+=GetPixelChannels(image);
2757               }
2758             if (fabs(pixel-p[center+i]) > MagickEpsilon)
2759               changes[id]++;
2760             gamma=PerceptibleReciprocal(gamma);
2761             if (count != 0)
2762               gamma*=(double) kernel->height/count;
2763             SetPixelChannel(morphology_image,channel,ClampToQuantum(gamma*
2764               pixel),q);
2765           }
2766           p+=GetPixelChannels(image);
2767           q+=GetPixelChannels(morphology_image);
2768         }
2769         if (SyncCacheViewAuthenticPixels(morphology_view,exception) == MagickFalse)
2770           status=MagickFalse;
2771         if (image->progress_monitor != (MagickProgressMonitor) NULL)
2772           {
2773             MagickBooleanType
2774               proceed;
2775 
2776 #if defined(MAGICKCORE_OPENMP_SUPPORT)
2777             #pragma omp atomic
2778 #endif
2779             progress++;
2780             proceed=SetImageProgress(image,MorphologyTag,progress,image->rows);
2781             if (proceed == MagickFalse)
2782               status=MagickFalse;
2783           }
2784       }
2785       morphology_image->type=image->type;
2786       morphology_view=DestroyCacheView(morphology_view);
2787       image_view=DestroyCacheView(image_view);
2788       for (j=0; j < (ssize_t) GetOpenMPMaximumThreads(); j++)
2789         changed+=changes[j];
2790       changes=(size_t *) RelinquishMagickMemory(changes);
2791       return(status ? (ssize_t) changed : 0);
2792     }
2793   /*
2794     Normal handling of horizontal or rectangular kernels (row by row).
2795   */
2796 #if defined(MAGICKCORE_OPENMP_SUPPORT)
2797   #pragma omp parallel for schedule(static) shared(progress,status) \
2798     magick_number_threads(image,morphology_image,image->rows,1)
2799 #endif
2800   for (y=0; y < (ssize_t) image->rows; y++)
2801   {
2802     const int
2803       id = GetOpenMPThreadId();
2804 
2805     register const Quantum
2806       *magick_restrict p;
2807 
2808     register Quantum
2809       *magick_restrict q;
2810 
2811     register ssize_t
2812       x;
2813 
2814     ssize_t
2815       center;
2816 
2817     if (status == MagickFalse)
2818       continue;
2819     p=GetCacheViewVirtualPixels(image_view,-offset.x,y-offset.y,width,
2820       kernel->height,exception);
2821     q=GetCacheViewAuthenticPixels(morphology_view,0,y,morphology_image->columns,
2822       1,exception);
2823     if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
2824       {
2825         status=MagickFalse;
2826         continue;
2827       }
2828     center=(ssize_t) (GetPixelChannels(image)*width*offset.y+
2829       GetPixelChannels(image)*offset.x);
2830     for (x=0; x < (ssize_t) image->columns; x++)
2831     {
2832       register ssize_t
2833         i;
2834 
2835       for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
2836       {
2837         double
2838           alpha,
2839           gamma,
2840           intensity,
2841           maximum,
2842           minimum,
2843           pixel;
2844 
2845         PixelChannel
2846           channel;
2847 
2848         PixelTrait
2849           morphology_traits,
2850           traits;
2851 
2852         register const MagickRealType
2853           *magick_restrict k;
2854 
2855         register const Quantum
2856           *magick_restrict pixels;
2857 
2858         register ssize_t
2859           u;
2860 
2861         size_t
2862           count;
2863 
2864         ssize_t
2865           v;
2866 
2867         channel=GetPixelChannelChannel(image,i);
2868         traits=GetPixelChannelTraits(image,channel);
2869         morphology_traits=GetPixelChannelTraits(morphology_image,channel);
2870         if ((traits == UndefinedPixelTrait) ||
2871             (morphology_traits == UndefinedPixelTrait))
2872           continue;
2873         if ((traits & CopyPixelTrait) != 0)
2874           {
2875             SetPixelChannel(morphology_image,channel,p[center+i],q);
2876             continue;
2877           }
2878         pixels=p;
2879         maximum=0.0;
2880         minimum=(double) QuantumRange;
2881         switch (method)
2882         {
2883           case ConvolveMorphology:
2884           {
2885             pixel=bias;
2886             break;
2887           }
2888           case DilateMorphology:
2889           case ErodeIntensityMorphology:
2890           {
2891             pixel=0.0;
2892             break;
2893           }
2894           case HitAndMissMorphology:
2895           case ErodeMorphology:
2896           {
2897             pixel=QuantumRange;
2898             break;
2899           }
2900           default:
2901           {
2902             pixel=(double) p[center+i];
2903             break;
2904           }
2905         }
2906         count=0;
2907         gamma=1.0;
2908         switch (method)
2909         {
2910           case ConvolveMorphology:
2911           {
2912             /*
2913                Weighted Average of pixels using reflected kernel
2914 
2915                For correct working of this operation for asymetrical kernels,
2916                the kernel needs to be applied in its reflected form.  That is
2917                its values needs to be reversed.
2918 
2919                Correlation is actually the same as this but without reflecting
2920                the kernel, and thus 'lower-level' that Convolution.  However as
2921                Convolution is the more common method used, and it does not
2922                really cost us much in terms of processing to use a reflected
2923                kernel, so it is Convolution that is implemented.
2924 
2925                Correlation will have its kernel reflected before calling this
2926                function to do a Convolve.
2927 
2928                For more details of Correlation vs Convolution see
2929                  http://www.cs.umd.edu/~djacobs/CMSC426/Convolution.pdf
2930             */
2931             k=(&kernel->values[kernel->width*kernel->height-1]);
2932             if ((morphology_traits & BlendPixelTrait) == 0)
2933               {
2934                 /*
2935                   No alpha blending.
2936                 */
2937                 for (v=0; v < (ssize_t) kernel->height; v++)
2938                 {
2939                   for (u=0; u < (ssize_t) kernel->width; u++)
2940                   {
2941                     if (!IsNaN(*k))
2942                       {
2943                         pixel+=(*k)*pixels[i];
2944                         count++;
2945                       }
2946                     k--;
2947                     pixels+=GetPixelChannels(image);
2948                   }
2949                   pixels+=(image->columns-1)*GetPixelChannels(image);
2950                 }
2951                 break;
2952               }
2953             /*
2954               Alpha blending.
2955             */
2956             gamma=0.0;
2957             for (v=0; v < (ssize_t) kernel->height; v++)
2958             {
2959               for (u=0; u < (ssize_t) kernel->width; u++)
2960               {
2961                 if (!IsNaN(*k))
2962                   {
2963                     alpha=(double) (QuantumScale*GetPixelAlpha(image,pixels));
2964                     pixel+=alpha*(*k)*pixels[i];
2965                     gamma+=alpha*(*k);
2966                     count++;
2967                   }
2968                 k--;
2969                 pixels+=GetPixelChannels(image);
2970               }
2971               pixels+=(image->columns-1)*GetPixelChannels(image);
2972             }
2973             break;
2974           }
2975           case ErodeMorphology:
2976           {
2977             /*
2978               Minimum value within kernel neighbourhood.
2979 
2980               The kernel is not reflected for this operation.  In normal
2981               Greyscale Morphology, the kernel value should be added
2982               to the real value, this is currently not done, due to the
2983               nature of the boolean kernels being used.
2984             */
2985             k=kernel->values;
2986             for (v=0; v < (ssize_t) kernel->height; v++)
2987             {
2988               for (u=0; u < (ssize_t) kernel->width; u++)
2989               {
2990                 if (!IsNaN(*k) && (*k >= 0.5))
2991                   {
2992                     if ((double) pixels[i] < pixel)
2993                       pixel=(double) pixels[i];
2994                   }
2995                 k++;
2996                 pixels+=GetPixelChannels(image);
2997               }
2998               pixels+=(image->columns-1)*GetPixelChannels(image);
2999             }
3000             break;
3001           }
3002           case DilateMorphology:
3003           {
3004             /*
3005                Maximum value within kernel neighbourhood.
3006 
3007                For correct working of this operation for asymetrical kernels,
3008                the kernel needs to be applied in its reflected form.  That is
3009                its values needs to be reversed.
3010 
3011                In normal Greyscale Morphology, the kernel value should be
3012                added to the real value, this is currently not done, due to the
3013                nature of the boolean kernels being used.
3014             */
3015             k=(&kernel->values[kernel->width*kernel->height-1]);
3016             for (v=0; v < (ssize_t) kernel->height; v++)
3017             {
3018               for (u=0; u < (ssize_t) kernel->width; u++)
3019               {
3020                 if (!IsNaN(*k) && (*k > 0.5))
3021                   {
3022                     if ((double) pixels[i] > pixel)
3023                       pixel=(double) pixels[i];
3024                   }
3025                 k--;
3026                 pixels+=GetPixelChannels(image);
3027               }
3028               pixels+=(image->columns-1)*GetPixelChannels(image);
3029             }
3030             break;
3031           }
3032           case HitAndMissMorphology:
3033           case ThinningMorphology:
3034           case ThickenMorphology:
3035           {
3036             /*
3037                Minimum of foreground pixel minus maxumum of background pixels.
3038 
3039                The kernel is not reflected for this operation, and consists
3040                of both foreground and background pixel neighbourhoods, 0.0 for
3041                background, and 1.0 for foreground with either Nan or 0.5 values
3042                for don't care.
3043 
3044                This never produces a meaningless negative result.  Such results
3045                cause Thinning/Thicken to not work correctly when used against a
3046                greyscale image.
3047             */
3048             k=kernel->values;
3049             for (v=0; v < (ssize_t) kernel->height; v++)
3050             {
3051               for (u=0; u < (ssize_t) kernel->width; u++)
3052               {
3053                 if (!IsNaN(*k))
3054                   {
3055                     if (*k > 0.7)
3056                       {
3057                         if ((double) pixels[i] < pixel)
3058                           pixel=(double) pixels[i];
3059                       }
3060                     else
3061                       if (*k < 0.3)
3062                         {
3063                           if ((double) pixels[i] > maximum)
3064                             maximum=(double) pixels[i];
3065                         }
3066                     count++;
3067                   }
3068                 k++;
3069                 pixels+=GetPixelChannels(image);
3070               }
3071               pixels+=(image->columns-1)*GetPixelChannels(image);
3072             }
3073             pixel-=maximum;
3074             if (pixel < 0.0)
3075               pixel=0.0;
3076             if (method ==  ThinningMorphology)
3077               pixel=(double) p[center+i]-pixel;
3078             else
3079               if (method ==  ThickenMorphology)
3080                 pixel+=(double) p[center+i]+pixel;
3081             break;
3082           }
3083           case ErodeIntensityMorphology:
3084           {
3085             /*
3086               Select pixel with minimum intensity within kernel neighbourhood.
3087 
3088               The kernel is not reflected for this operation.
3089             */
3090             k=kernel->values;
3091             for (v=0; v < (ssize_t) kernel->height; v++)
3092             {
3093               for (u=0; u < (ssize_t) kernel->width; u++)
3094               {
3095                 if (!IsNaN(*k) && (*k >= 0.5))
3096                   {
3097                     intensity=(double) GetPixelIntensity(image,pixels);
3098                     if (intensity < minimum)
3099                       {
3100                         pixel=(double) pixels[i];
3101                         minimum=intensity;
3102                       }
3103                     count++;
3104                   }
3105                 k++;
3106                 pixels+=GetPixelChannels(image);
3107               }
3108               pixels+=(image->columns-1)*GetPixelChannels(image);
3109             }
3110             break;
3111           }
3112           case DilateIntensityMorphology:
3113           {
3114             /*
3115               Select pixel with maximum intensity within kernel neighbourhood.
3116 
3117               The kernel is not reflected for this operation.
3118             */
3119             k=(&kernel->values[kernel->width*kernel->height-1]);
3120             for (v=0; v < (ssize_t) kernel->height; v++)
3121             {
3122               for (u=0; u < (ssize_t) kernel->width; u++)
3123               {
3124                 if (!IsNaN(*k) && (*k >= 0.5))
3125                   {
3126                     intensity=(double) GetPixelIntensity(image,pixels);
3127                     if (intensity > maximum)
3128                       {
3129                         pixel=(double) pixels[i];
3130                         maximum=intensity;
3131                       }
3132                     count++;
3133                   }
3134                 k--;
3135                 pixels+=GetPixelChannels(image);
3136               }
3137               pixels+=(image->columns-1)*GetPixelChannels(image);
3138             }
3139             break;
3140           }
3141           case IterativeDistanceMorphology:
3142           {
3143             /*
3144                Compute th iterative distance from black edge of a white image
3145                shape.  Essentually white values are decreased to the smallest
3146                'distance from edge' it can find.
3147 
3148                It works by adding kernel values to the neighbourhood, and and
3149                select the minimum value found. The kernel is rotated before
3150                use, so kernel distances match resulting distances, when a user
3151                provided asymmetric kernel is applied.
3152 
3153                This code is nearly identical to True GrayScale Morphology but
3154                not quite.
3155 
3156                GreyDilate Kernel values added, maximum value found Kernel is
3157                rotated before use.
3158 
3159                GrayErode:  Kernel values subtracted and minimum value found No
3160                kernel rotation used.
3161 
3162                Note the the Iterative Distance method is essentially a
3163                GrayErode, but with negative kernel values, and kernel rotation
3164                applied.
3165             */
3166             k=(&kernel->values[kernel->width*kernel->height-1]);
3167             for (v=0; v < (ssize_t) kernel->height; v++)
3168             {
3169               for (u=0; u < (ssize_t) kernel->width; u++)
3170               {
3171                 if (!IsNaN(*k))
3172                   {
3173                     if ((pixels[i]+(*k)) < pixel)
3174                       pixel=(double) pixels[i]+(*k);
3175                     count++;
3176                   }
3177                 k--;
3178                 pixels+=GetPixelChannels(image);
3179               }
3180               pixels+=(image->columns-1)*GetPixelChannels(image);
3181             }
3182             break;
3183           }
3184           case UndefinedMorphology:
3185           default:
3186             break;
3187         }
3188         if (fabs(pixel-p[center+i]) > MagickEpsilon)
3189           changes[id]++;
3190         gamma=PerceptibleReciprocal(gamma);
3191         if (count != 0)
3192           gamma*=(double) kernel->height*kernel->width/count;
3193         SetPixelChannel(morphology_image,channel,ClampToQuantum(gamma*pixel),q);
3194       }
3195       p+=GetPixelChannels(image);
3196       q+=GetPixelChannels(morphology_image);
3197     }
3198     if (SyncCacheViewAuthenticPixels(morphology_view,exception) == MagickFalse)
3199       status=MagickFalse;
3200     if (image->progress_monitor != (MagickProgressMonitor) NULL)
3201       {
3202         MagickBooleanType
3203           proceed;
3204 
3205 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3206         #pragma omp atomic
3207 #endif
3208         progress++;
3209         proceed=SetImageProgress(image,MorphologyTag,progress,image->rows);
3210         if (proceed == MagickFalse)
3211           status=MagickFalse;
3212       }
3213   }
3214   morphology_view=DestroyCacheView(morphology_view);
3215   image_view=DestroyCacheView(image_view);
3216   for (j=0; j < (ssize_t) GetOpenMPMaximumThreads(); j++)
3217     changed+=changes[j];
3218   changes=(size_t *) RelinquishMagickMemory(changes);
3219   return(status ? (ssize_t) changed : -1);
3220 }
3221 
3222 /*
3223   This is almost identical to the MorphologyPrimative() function above, but
3224   applies the primitive directly to the actual image using two passes, once in
3225   each direction, with the results of the previous (and current) row being
3226   re-used.
3227 
3228   That is after each row is 'Sync'ed' into the image, the next row makes use of
3229   those values as part of the calculation of the next row.  It repeats, but
3230   going in the oppisite (bottom-up) direction.
3231 
3232   Because of this 're-use of results' this function can not make use of multi-
3233   threaded, parellel processing.
3234 */
MorphologyPrimitiveDirect(Image * image,const MorphologyMethod method,const KernelInfo * kernel,ExceptionInfo * exception)3235 static ssize_t MorphologyPrimitiveDirect(Image *image,
3236   const MorphologyMethod method,const KernelInfo *kernel,
3237   ExceptionInfo *exception)
3238 {
3239   CacheView
3240     *morphology_view,
3241     *image_view;
3242 
3243   MagickBooleanType
3244     status;
3245 
3246   MagickOffsetType
3247     progress;
3248 
3249   OffsetInfo
3250     offset;
3251 
3252   size_t
3253     width,
3254     changed;
3255 
3256   ssize_t
3257     y;
3258 
3259   assert(image != (Image *) NULL);
3260   assert(image->signature == MagickCoreSignature);
3261   assert(kernel != (KernelInfo *) NULL);
3262   assert(kernel->signature == MagickCoreSignature);
3263   assert(exception != (ExceptionInfo *) NULL);
3264   assert(exception->signature == MagickCoreSignature);
3265   status=MagickTrue;
3266   changed=0;
3267   progress=0;
3268   switch(method)
3269   {
3270     case DistanceMorphology:
3271     case VoronoiMorphology:
3272     {
3273       /*
3274         Kernel reflected about origin.
3275       */
3276       offset.x=(ssize_t) kernel->width-kernel->x-1;
3277       offset.y=(ssize_t) kernel->height-kernel->y-1;
3278       break;
3279     }
3280     default:
3281     {
3282       offset.x=kernel->x;
3283       offset.y=kernel->y;
3284       break;
3285     }
3286   }
3287   /*
3288     Two views into same image, do not thread.
3289   */
3290   image_view=AcquireVirtualCacheView(image,exception);
3291   morphology_view=AcquireAuthenticCacheView(image,exception);
3292   width=image->columns+kernel->width-1;
3293   for (y=0; y < (ssize_t) image->rows; y++)
3294   {
3295     register const Quantum
3296       *magick_restrict p;
3297 
3298     register Quantum
3299       *magick_restrict q;
3300 
3301     register ssize_t
3302       x;
3303 
3304     /*
3305       Read virtual pixels, and authentic pixels, from the same image!  We read
3306       using virtual to get virtual pixel handling, but write back into the same
3307       image.
3308 
3309       Only top half of kernel is processed as we do a single pass downward
3310       through the image iterating the distance function as we go.
3311     */
3312     if (status == MagickFalse)
3313       continue;
3314     p=GetCacheViewVirtualPixels(image_view,-offset.x,y-offset.y,width,(size_t)
3315       offset.y+1,exception);
3316     q=GetCacheViewAuthenticPixels(morphology_view,0,y,image->columns,1,
3317       exception);
3318     if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
3319       {
3320         status=MagickFalse;
3321         continue;
3322       }
3323     for (x=0; x < (ssize_t) image->columns; x++)
3324     {
3325       register ssize_t
3326         i;
3327 
3328       for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
3329       {
3330         double
3331           pixel;
3332 
3333         PixelChannel
3334           channel;
3335 
3336         PixelTrait
3337           traits;
3338 
3339         register const MagickRealType
3340           *magick_restrict k;
3341 
3342         register const Quantum
3343           *magick_restrict pixels;
3344 
3345         register ssize_t
3346           u;
3347 
3348         ssize_t
3349           v;
3350 
3351         channel=GetPixelChannelChannel(image,i);
3352         traits=GetPixelChannelTraits(image,channel);
3353         if (traits == UndefinedPixelTrait)
3354           continue;
3355         if ((traits & CopyPixelTrait) != 0)
3356           continue;
3357         pixels=p;
3358         pixel=(double) QuantumRange;
3359         switch (method)
3360         {
3361           case DistanceMorphology:
3362           {
3363             k=(&kernel->values[kernel->width*kernel->height-1]);
3364             for (v=0; v <= offset.y; v++)
3365             {
3366               for (u=0; u < (ssize_t) kernel->width; u++)
3367               {
3368                 if (!IsNaN(*k))
3369                   {
3370                     if ((pixels[i]+(*k)) < pixel)
3371                       pixel=(double) pixels[i]+(*k);
3372                   }
3373                 k--;
3374                 pixels+=GetPixelChannels(image);
3375               }
3376               pixels+=(image->columns-1)*GetPixelChannels(image);
3377             }
3378             k=(&kernel->values[kernel->width*(kernel->y+1)-1]);
3379             pixels=q-offset.x*GetPixelChannels(image);
3380             for (u=0; u < offset.x; u++)
3381             {
3382               if (!IsNaN(*k) && ((x+u-offset.x) >= 0))
3383                 {
3384                   if ((pixels[i]+(*k)) < pixel)
3385                     pixel=(double) pixels[i]+(*k);
3386                 }
3387               k--;
3388               pixels+=GetPixelChannels(image);
3389             }
3390             break;
3391           }
3392           case VoronoiMorphology:
3393           {
3394             k=(&kernel->values[kernel->width*kernel->height-1]);
3395             for (v=0; v < offset.y; v++)
3396             {
3397               for (u=0; u < (ssize_t) kernel->width; u++)
3398               {
3399                 if (!IsNaN(*k))
3400                   {
3401                     if ((pixels[i]+(*k)) < pixel)
3402                       pixel=(double) pixels[i]+(*k);
3403                   }
3404                 k--;
3405                 pixels+=GetPixelChannels(image);
3406               }
3407               pixels+=(image->columns-1)*GetPixelChannels(image);
3408             }
3409             k=(&kernel->values[kernel->width*(kernel->y+1)-1]);
3410             pixels=q-offset.x*GetPixelChannels(image);
3411             for (u=0; u < offset.x; u++)
3412             {
3413               if (!IsNaN(*k) && ((x+u-offset.x) >= 0))
3414                 {
3415                   if ((pixels[i]+(*k)) < pixel)
3416                     pixel=(double) pixels[i]+(*k);
3417                 }
3418               k--;
3419               pixels+=GetPixelChannels(image);
3420             }
3421             break;
3422           }
3423           default:
3424             break;
3425         }
3426         if (fabs(pixel-q[i]) > MagickEpsilon)
3427           changed++;
3428         q[i]=ClampToQuantum(pixel);
3429       }
3430       p+=GetPixelChannels(image);
3431       q+=GetPixelChannels(image);
3432     }
3433     if (SyncCacheViewAuthenticPixels(morphology_view,exception) == MagickFalse)
3434       status=MagickFalse;
3435     if (image->progress_monitor != (MagickProgressMonitor) NULL)
3436       {
3437         MagickBooleanType
3438           proceed;
3439 
3440 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3441         #pragma omp atomic
3442 #endif
3443         progress++;
3444         proceed=SetImageProgress(image,MorphologyTag,progress,2*image->rows);
3445         if (proceed == MagickFalse)
3446           status=MagickFalse;
3447       }
3448   }
3449   morphology_view=DestroyCacheView(morphology_view);
3450   image_view=DestroyCacheView(image_view);
3451   /*
3452     Do the reverse pass through the image.
3453   */
3454   image_view=AcquireVirtualCacheView(image,exception);
3455   morphology_view=AcquireAuthenticCacheView(image,exception);
3456   for (y=(ssize_t) image->rows-1; y >= 0; y--)
3457   {
3458     register const Quantum
3459       *magick_restrict p;
3460 
3461     register Quantum
3462       *magick_restrict q;
3463 
3464     register ssize_t
3465       x;
3466 
3467     /*
3468        Read virtual pixels, and authentic pixels, from the same image.  We
3469        read using virtual to get virtual pixel handling, but write back
3470        into the same image.
3471 
3472        Only the bottom half of the kernel is processed as we up the image.
3473     */
3474     if (status == MagickFalse)
3475       continue;
3476     p=GetCacheViewVirtualPixels(image_view,-offset.x,y,width,(size_t)
3477       kernel->y+1,exception);
3478     q=GetCacheViewAuthenticPixels(morphology_view,0,y,image->columns,1,
3479       exception);
3480     if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
3481       {
3482         status=MagickFalse;
3483         continue;
3484       }
3485     p+=(image->columns-1)*GetPixelChannels(image);
3486     q+=(image->columns-1)*GetPixelChannels(image);
3487     for (x=(ssize_t) image->columns-1; x >= 0; x--)
3488     {
3489       register ssize_t
3490         i;
3491 
3492       for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
3493       {
3494         double
3495           pixel;
3496 
3497         PixelChannel
3498           channel;
3499 
3500         PixelTrait
3501           traits;
3502 
3503         register const MagickRealType
3504           *magick_restrict k;
3505 
3506         register const Quantum
3507           *magick_restrict pixels;
3508 
3509         register ssize_t
3510           u;
3511 
3512         ssize_t
3513           v;
3514 
3515         channel=GetPixelChannelChannel(image,i);
3516         traits=GetPixelChannelTraits(image,channel);
3517         if (traits == UndefinedPixelTrait)
3518           continue;
3519         if ((traits & CopyPixelTrait) != 0)
3520           continue;
3521         pixels=p;
3522         pixel=(double) QuantumRange;
3523         switch (method)
3524         {
3525           case DistanceMorphology:
3526           {
3527             k=(&kernel->values[kernel->width*(kernel->y+1)-1]);
3528             for (v=offset.y; v < (ssize_t) kernel->height; v++)
3529             {
3530               for (u=0; u < (ssize_t) kernel->width; u++)
3531               {
3532                 if (!IsNaN(*k))
3533                   {
3534                     if ((pixels[i]+(*k)) < pixel)
3535                       pixel=(double) pixels[i]+(*k);
3536                   }
3537                 k--;
3538                 pixels+=GetPixelChannels(image);
3539               }
3540               pixels+=(image->columns-1)*GetPixelChannels(image);
3541             }
3542             k=(&kernel->values[kernel->width*kernel->y+kernel->x-1]);
3543             pixels=q;
3544             for (u=offset.x+1; u < (ssize_t) kernel->width; u++)
3545             {
3546               pixels+=GetPixelChannels(image);
3547               if (!IsNaN(*k) && ((x+u-offset.x) < (ssize_t) image->columns))
3548                 {
3549                   if ((pixels[i]+(*k)) < pixel)
3550                     pixel=(double) pixels[i]+(*k);
3551                 }
3552               k--;
3553             }
3554             break;
3555           }
3556           case VoronoiMorphology:
3557           {
3558             k=(&kernel->values[kernel->width*(kernel->y+1)-1]);
3559             for (v=offset.y; v < (ssize_t) kernel->height; v++)
3560             {
3561               for (u=0; u < (ssize_t) kernel->width; u++)
3562               {
3563                 if (!IsNaN(*k))
3564                   {
3565                     if ((pixels[i]+(*k)) < pixel)
3566                       pixel=(double) pixels[i]+(*k);
3567                   }
3568                 k--;
3569                 pixels+=GetPixelChannels(image);
3570               }
3571               pixels+=(image->columns-1)*GetPixelChannels(image);
3572             }
3573             k=(&kernel->values[kernel->width*(kernel->y+1)-1]);
3574             pixels=q;
3575             for (u=offset.x+1; u < (ssize_t) kernel->width; u++)
3576             {
3577               pixels+=GetPixelChannels(image);
3578               if (!IsNaN(*k) && ((x+u-offset.x) < (ssize_t) image->columns))
3579                 {
3580                   if ((pixels[i]+(*k)) < pixel)
3581                     pixel=(double) pixels[i]+(*k);
3582                 }
3583               k--;
3584             }
3585             break;
3586           }
3587           default:
3588             break;
3589         }
3590         if (fabs(pixel-q[i]) > MagickEpsilon)
3591           changed++;
3592         q[i]=ClampToQuantum(pixel);
3593       }
3594       p-=GetPixelChannels(image);
3595       q-=GetPixelChannels(image);
3596     }
3597     if (SyncCacheViewAuthenticPixels(morphology_view,exception) == MagickFalse)
3598       status=MagickFalse;
3599     if (image->progress_monitor != (MagickProgressMonitor) NULL)
3600       {
3601         MagickBooleanType
3602           proceed;
3603 
3604 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3605         #pragma omp atomic
3606 #endif
3607         progress++;
3608         proceed=SetImageProgress(image,MorphologyTag,progress,2*image->rows);
3609         if (proceed == MagickFalse)
3610           status=MagickFalse;
3611       }
3612   }
3613   morphology_view=DestroyCacheView(morphology_view);
3614   image_view=DestroyCacheView(image_view);
3615   return(status ? (ssize_t) changed : -1);
3616 }
3617 
3618 /*
3619   Apply a Morphology by calling one of the above low level primitive
3620   application functions.  This function handles any iteration loops,
3621   composition or re-iteration of results, and compound morphology methods that
3622   is based on multiple low-level (staged) morphology methods.
3623 
3624   Basically this provides the complex glue between the requested morphology
3625   method and raw low-level implementation (above).
3626 */
MorphologyApply(const Image * image,const MorphologyMethod method,const ssize_t iterations,const KernelInfo * kernel,const CompositeOperator compose,const double bias,ExceptionInfo * exception)3627 MagickPrivate Image *MorphologyApply(const Image *image,
3628   const MorphologyMethod method, const ssize_t iterations,
3629   const KernelInfo *kernel, const CompositeOperator compose,const double bias,
3630   ExceptionInfo *exception)
3631 {
3632   CompositeOperator
3633     curr_compose;
3634 
3635   Image
3636     *curr_image,    /* Image we are working with or iterating */
3637     *work_image,    /* secondary image for primitive iteration */
3638     *save_image,    /* saved image - for 'edge' method only */
3639     *rslt_image;    /* resultant image - after multi-kernel handling */
3640 
3641   KernelInfo
3642     *reflected_kernel, /* A reflected copy of the kernel (if needed) */
3643     *norm_kernel,      /* the current normal un-reflected kernel */
3644     *rflt_kernel,      /* the current reflected kernel (if needed) */
3645     *this_kernel;      /* the kernel being applied */
3646 
3647   MorphologyMethod
3648     primitive;      /* the current morphology primitive being applied */
3649 
3650   CompositeOperator
3651     rslt_compose;   /* multi-kernel compose method for results to use */
3652 
3653   MagickBooleanType
3654     special,        /* do we use a direct modify function? */
3655     verbose;        /* verbose output of results */
3656 
3657   size_t
3658     method_loop,    /* Loop 1: number of compound method iterations (norm 1) */
3659     method_limit,   /*         maximum number of compound method iterations */
3660     kernel_number,  /* Loop 2: the kernel number being applied */
3661     stage_loop,     /* Loop 3: primitive loop for compound morphology */
3662     stage_limit,    /*         how many primitives are in this compound */
3663     kernel_loop,    /* Loop 4: iterate the kernel over image */
3664     kernel_limit,   /*         number of times to iterate kernel */
3665     count,          /* total count of primitive steps applied */
3666     kernel_changed, /* total count of changed using iterated kernel */
3667     method_changed; /* total count of changed over method iteration */
3668 
3669   ssize_t
3670     changed;        /* number pixels changed by last primitive operation */
3671 
3672   char
3673     v_info[MagickPathExtent];
3674 
3675   assert(image != (Image *) NULL);
3676   assert(image->signature == MagickCoreSignature);
3677   assert(kernel != (KernelInfo *) NULL);
3678   assert(kernel->signature == MagickCoreSignature);
3679   assert(exception != (ExceptionInfo *) NULL);
3680   assert(exception->signature == MagickCoreSignature);
3681 
3682   count = 0;      /* number of low-level morphology primitives performed */
3683   if ( iterations == 0 )
3684     return((Image *) NULL);   /* null operation - nothing to do! */
3685 
3686   kernel_limit = (size_t) iterations;
3687   if ( iterations < 0 )  /* negative interations = infinite (well alomst) */
3688      kernel_limit = image->columns>image->rows ? image->columns : image->rows;
3689 
3690   verbose = IsStringTrue(GetImageArtifact(image,"debug"));
3691 
3692   /* initialise for cleanup */
3693   curr_image = (Image *) image;
3694   curr_compose = image->compose;
3695   (void) curr_compose;
3696   work_image = save_image = rslt_image = (Image *) NULL;
3697   reflected_kernel = (KernelInfo *) NULL;
3698 
3699   /* Initialize specific methods
3700    * + which loop should use the given iteratations
3701    * + how many primitives make up the compound morphology
3702    * + multi-kernel compose method to use (by default)
3703    */
3704   method_limit = 1;       /* just do method once, unless otherwise set */
3705   stage_limit = 1;        /* assume method is not a compound */
3706   special = MagickFalse;   /* assume it is NOT a direct modify primitive */
3707   rslt_compose = compose; /* and we are composing multi-kernels as given */
3708   switch( method ) {
3709     case SmoothMorphology:  /* 4 primitive compound morphology */
3710       stage_limit = 4;
3711       break;
3712     case OpenMorphology:    /* 2 primitive compound morphology */
3713     case OpenIntensityMorphology:
3714     case TopHatMorphology:
3715     case CloseMorphology:
3716     case CloseIntensityMorphology:
3717     case BottomHatMorphology:
3718     case EdgeMorphology:
3719       stage_limit = 2;
3720       break;
3721     case HitAndMissMorphology:
3722       rslt_compose = LightenCompositeOp;  /* Union of multi-kernel results */
3723       /* FALL THUR */
3724     case ThinningMorphology:
3725     case ThickenMorphology:
3726       method_limit = kernel_limit;  /* iterate the whole method */
3727       kernel_limit = 1;             /* do not do kernel iteration  */
3728       break;
3729     case DistanceMorphology:
3730     case VoronoiMorphology:
3731       special = MagickTrue;         /* use special direct primative */
3732       break;
3733     default:
3734       break;
3735   }
3736 
3737   /* Apply special methods with special requirments
3738   ** For example, single run only, or post-processing requirements
3739   */
3740   if ( special != MagickFalse )
3741     {
3742       rslt_image=CloneImage(image,0,0,MagickTrue,exception);
3743       if (rslt_image == (Image *) NULL)
3744         goto error_cleanup;
3745       if (SetImageStorageClass(rslt_image,DirectClass,exception) == MagickFalse)
3746         goto error_cleanup;
3747 
3748       changed=MorphologyPrimitiveDirect(rslt_image,method,kernel,exception);
3749 
3750       if (verbose != MagickFalse)
3751         (void) (void) FormatLocaleFile(stderr,
3752           "%s:%.20g.%.20g #%.20g => Changed %.20g\n",
3753           CommandOptionToMnemonic(MagickMorphologyOptions, method),
3754           1.0,0.0,1.0, (double) changed);
3755 
3756       if ( changed < 0 )
3757         goto error_cleanup;
3758 
3759       if ( method == VoronoiMorphology ) {
3760         /* Preserve the alpha channel of input image - but turned it off */
3761         (void) SetImageAlphaChannel(rslt_image, DeactivateAlphaChannel,
3762           exception);
3763         (void) CompositeImage(rslt_image,image,CopyAlphaCompositeOp,
3764           MagickTrue,0,0,exception);
3765         (void) SetImageAlphaChannel(rslt_image, DeactivateAlphaChannel,
3766           exception);
3767       }
3768       goto exit_cleanup;
3769     }
3770 
3771   /* Handle user (caller) specified multi-kernel composition method */
3772   if ( compose != UndefinedCompositeOp )
3773     rslt_compose = compose;  /* override default composition for method */
3774   if ( rslt_compose == UndefinedCompositeOp )
3775     rslt_compose = NoCompositeOp; /* still not defined! Then re-iterate */
3776 
3777   /* Some methods require a reflected kernel to use with primitives.
3778    * Create the reflected kernel for those methods. */
3779   switch ( method ) {
3780     case CorrelateMorphology:
3781     case CloseMorphology:
3782     case CloseIntensityMorphology:
3783     case BottomHatMorphology:
3784     case SmoothMorphology:
3785       reflected_kernel = CloneKernelInfo(kernel);
3786       if (reflected_kernel == (KernelInfo *) NULL)
3787         goto error_cleanup;
3788       RotateKernelInfo(reflected_kernel,180);
3789       break;
3790     default:
3791       break;
3792   }
3793 
3794   /* Loops around more primitive morpholgy methods
3795   **  erose, dilate, open, close, smooth, edge, etc...
3796   */
3797   /* Loop 1:  iterate the compound method */
3798   method_loop = 0;
3799   method_changed = 1;
3800   while ( method_loop < method_limit && method_changed > 0 ) {
3801     method_loop++;
3802     method_changed = 0;
3803 
3804     /* Loop 2:  iterate over each kernel in a multi-kernel list */
3805     norm_kernel = (KernelInfo *) kernel;
3806     this_kernel = (KernelInfo *) kernel;
3807     rflt_kernel = reflected_kernel;
3808 
3809     kernel_number = 0;
3810     while ( norm_kernel != NULL ) {
3811 
3812       /* Loop 3: Compound Morphology Staging - Select Primative to apply */
3813       stage_loop = 0;          /* the compound morphology stage number */
3814       while ( stage_loop < stage_limit ) {
3815         stage_loop++;   /* The stage of the compound morphology */
3816 
3817         /* Select primitive morphology for this stage of compound method */
3818         this_kernel = norm_kernel; /* default use unreflected kernel */
3819         primitive = method;        /* Assume method is a primitive */
3820         switch( method ) {
3821           case ErodeMorphology:      /* just erode */
3822           case EdgeInMorphology:     /* erode and image difference */
3823             primitive = ErodeMorphology;
3824             break;
3825           case DilateMorphology:     /* just dilate */
3826           case EdgeOutMorphology:    /* dilate and image difference */
3827             primitive = DilateMorphology;
3828             break;
3829           case OpenMorphology:       /* erode then dialate */
3830           case TopHatMorphology:     /* open and image difference */
3831             primitive = ErodeMorphology;
3832             if ( stage_loop == 2 )
3833               primitive = DilateMorphology;
3834             break;
3835           case OpenIntensityMorphology:
3836             primitive = ErodeIntensityMorphology;
3837             if ( stage_loop == 2 )
3838               primitive = DilateIntensityMorphology;
3839             break;
3840           case CloseMorphology:      /* dilate, then erode */
3841           case BottomHatMorphology:  /* close and image difference */
3842             this_kernel = rflt_kernel; /* use the reflected kernel */
3843             primitive = DilateMorphology;
3844             if ( stage_loop == 2 )
3845               primitive = ErodeMorphology;
3846             break;
3847           case CloseIntensityMorphology:
3848             this_kernel = rflt_kernel; /* use the reflected kernel */
3849             primitive = DilateIntensityMorphology;
3850             if ( stage_loop == 2 )
3851               primitive = ErodeIntensityMorphology;
3852             break;
3853           case SmoothMorphology:         /* open, close */
3854             switch ( stage_loop ) {
3855               case 1: /* start an open method, which starts with Erode */
3856                 primitive = ErodeMorphology;
3857                 break;
3858               case 2:  /* now Dilate the Erode */
3859                 primitive = DilateMorphology;
3860                 break;
3861               case 3:  /* Reflect kernel a close */
3862                 this_kernel = rflt_kernel; /* use the reflected kernel */
3863                 primitive = DilateMorphology;
3864                 break;
3865               case 4:  /* Finish the Close */
3866                 this_kernel = rflt_kernel; /* use the reflected kernel */
3867                 primitive = ErodeMorphology;
3868                 break;
3869             }
3870             break;
3871           case EdgeMorphology:        /* dilate and erode difference */
3872             primitive = DilateMorphology;
3873             if ( stage_loop == 2 ) {
3874               save_image = curr_image;      /* save the image difference */
3875               curr_image = (Image *) image;
3876               primitive = ErodeMorphology;
3877             }
3878             break;
3879           case CorrelateMorphology:
3880             /* A Correlation is a Convolution with a reflected kernel.
3881             ** However a Convolution is a weighted sum using a reflected
3882             ** kernel.  It may seem stange to convert a Correlation into a
3883             ** Convolution as the Correlation is the simplier method, but
3884             ** Convolution is much more commonly used, and it makes sense to
3885             ** implement it directly so as to avoid the need to duplicate the
3886             ** kernel when it is not required (which is typically the
3887             ** default).
3888             */
3889             this_kernel = rflt_kernel; /* use the reflected kernel */
3890             primitive = ConvolveMorphology;
3891             break;
3892           default:
3893             break;
3894         }
3895         assert( this_kernel != (KernelInfo *) NULL );
3896 
3897         /* Extra information for debugging compound operations */
3898         if (verbose != MagickFalse) {
3899           if ( stage_limit > 1 )
3900             (void) FormatLocaleString(v_info,MagickPathExtent,"%s:%.20g.%.20g -> ",
3901              CommandOptionToMnemonic(MagickMorphologyOptions,method),(double)
3902              method_loop,(double) stage_loop);
3903           else if ( primitive != method )
3904             (void) FormatLocaleString(v_info, MagickPathExtent, "%s:%.20g -> ",
3905               CommandOptionToMnemonic(MagickMorphologyOptions, method),(double)
3906               method_loop);
3907           else
3908             v_info[0] = '\0';
3909         }
3910 
3911         /* Loop 4: Iterate the kernel with primitive */
3912         kernel_loop = 0;
3913         kernel_changed = 0;
3914         changed = 1;
3915         while ( kernel_loop < kernel_limit && changed > 0 ) {
3916           kernel_loop++;     /* the iteration of this kernel */
3917 
3918           /* Create a clone as the destination image, if not yet defined */
3919           if ( work_image == (Image *) NULL )
3920             {
3921               work_image=CloneImage(image,0,0,MagickTrue,exception);
3922               if (work_image == (Image *) NULL)
3923                 goto error_cleanup;
3924               if (SetImageStorageClass(work_image,DirectClass,exception) == MagickFalse)
3925                 goto error_cleanup;
3926             }
3927 
3928           /* APPLY THE MORPHOLOGICAL PRIMITIVE (curr -> work) */
3929           count++;
3930           changed = MorphologyPrimitive(curr_image, work_image, primitive,
3931                        this_kernel, bias, exception);
3932           if (verbose != MagickFalse) {
3933             if ( kernel_loop > 1 )
3934               (void) FormatLocaleFile(stderr, "\n"); /* add end-of-line from previous */
3935             (void) (void) FormatLocaleFile(stderr,
3936               "%s%s%s:%.20g.%.20g #%.20g => Changed %.20g",
3937               v_info,CommandOptionToMnemonic(MagickMorphologyOptions,
3938               primitive),(this_kernel == rflt_kernel ) ? "*" : "",
3939               (double) (method_loop+kernel_loop-1),(double) kernel_number,
3940               (double) count,(double) changed);
3941           }
3942           if ( changed < 0 )
3943             goto error_cleanup;
3944           kernel_changed += changed;
3945           method_changed += changed;
3946 
3947           /* prepare next loop */
3948           { Image *tmp = work_image;   /* swap images for iteration */
3949             work_image = curr_image;
3950             curr_image = tmp;
3951           }
3952           if ( work_image == image )
3953             work_image = (Image *) NULL; /* replace input 'image' */
3954 
3955         } /* End Loop 4: Iterate the kernel with primitive */
3956 
3957         if (verbose != MagickFalse && kernel_changed != (size_t)changed)
3958           (void) FormatLocaleFile(stderr, "   Total %.20g",(double) kernel_changed);
3959         if (verbose != MagickFalse && stage_loop < stage_limit)
3960           (void) FormatLocaleFile(stderr, "\n"); /* add end-of-line before looping */
3961 
3962 #if 0
3963     (void) FormatLocaleFile(stderr, "--E-- image=0x%lx\n", (unsigned long)image);
3964     (void) FormatLocaleFile(stderr, "      curr =0x%lx\n", (unsigned long)curr_image);
3965     (void) FormatLocaleFile(stderr, "      work =0x%lx\n", (unsigned long)work_image);
3966     (void) FormatLocaleFile(stderr, "      save =0x%lx\n", (unsigned long)save_image);
3967     (void) FormatLocaleFile(stderr, "      union=0x%lx\n", (unsigned long)rslt_image);
3968 #endif
3969 
3970       } /* End Loop 3: Primative (staging) Loop for Coumpound Methods */
3971 
3972       /*  Final Post-processing for some Compound Methods
3973       **
3974       ** The removal of any 'Sync' channel flag in the Image Compositon
3975       ** below ensures the methematical compose method is applied in a
3976       ** purely mathematical way, and only to the selected channels.
3977       ** Turn off SVG composition 'alpha blending'.
3978       */
3979       switch( method ) {
3980         case EdgeOutMorphology:
3981         case EdgeInMorphology:
3982         case TopHatMorphology:
3983         case BottomHatMorphology:
3984           if (verbose != MagickFalse)
3985             (void) FormatLocaleFile(stderr,
3986               "\n%s: Difference with original image",CommandOptionToMnemonic(
3987               MagickMorphologyOptions, method) );
3988           (void) CompositeImage(curr_image,image,DifferenceCompositeOp,
3989             MagickTrue,0,0,exception);
3990           break;
3991         case EdgeMorphology:
3992           if (verbose != MagickFalse)
3993             (void) FormatLocaleFile(stderr,
3994               "\n%s: Difference of Dilate and Erode",CommandOptionToMnemonic(
3995               MagickMorphologyOptions, method) );
3996           (void) CompositeImage(curr_image,save_image,DifferenceCompositeOp,
3997             MagickTrue,0,0,exception);
3998           save_image = DestroyImage(save_image); /* finished with save image */
3999           break;
4000         default:
4001           break;
4002       }
4003 
4004       /* multi-kernel handling:  re-iterate, or compose results */
4005       if ( kernel->next == (KernelInfo *) NULL )
4006         rslt_image = curr_image;   /* just return the resulting image */
4007       else if ( rslt_compose == NoCompositeOp )
4008         { if (verbose != MagickFalse) {
4009             if ( this_kernel->next != (KernelInfo *) NULL )
4010               (void) FormatLocaleFile(stderr, " (re-iterate)");
4011             else
4012               (void) FormatLocaleFile(stderr, " (done)");
4013           }
4014           rslt_image = curr_image; /* return result, and re-iterate */
4015         }
4016       else if ( rslt_image == (Image *) NULL)
4017         { if (verbose != MagickFalse)
4018             (void) FormatLocaleFile(stderr, " (save for compose)");
4019           rslt_image = curr_image;
4020           curr_image = (Image *) image;  /* continue with original image */
4021         }
4022       else
4023         { /* Add the new 'current' result to the composition
4024           **
4025           ** The removal of any 'Sync' channel flag in the Image Compositon
4026           ** below ensures the methematical compose method is applied in a
4027           ** purely mathematical way, and only to the selected channels.
4028           ** IE: Turn off SVG composition 'alpha blending'.
4029           */
4030           if (verbose != MagickFalse)
4031             (void) FormatLocaleFile(stderr, " (compose \"%s\")",
4032               CommandOptionToMnemonic(MagickComposeOptions, rslt_compose) );
4033           (void) CompositeImage(rslt_image,curr_image,rslt_compose,MagickTrue,
4034             0,0,exception);
4035           curr_image = DestroyImage(curr_image);
4036           curr_image = (Image *) image;  /* continue with original image */
4037         }
4038       if (verbose != MagickFalse)
4039         (void) FormatLocaleFile(stderr, "\n");
4040 
4041       /* loop to the next kernel in a multi-kernel list */
4042       norm_kernel = norm_kernel->next;
4043       if ( rflt_kernel != (KernelInfo *) NULL )
4044         rflt_kernel = rflt_kernel->next;
4045       kernel_number++;
4046     } /* End Loop 2: Loop over each kernel */
4047 
4048   } /* End Loop 1: compound method interation */
4049 
4050   goto exit_cleanup;
4051 
4052   /* Yes goto's are bad, but it makes cleanup lot more efficient */
4053 error_cleanup:
4054   if ( curr_image == rslt_image )
4055     curr_image = (Image *) NULL;
4056   if ( rslt_image != (Image *) NULL )
4057     rslt_image = DestroyImage(rslt_image);
4058 exit_cleanup:
4059   if ( curr_image == rslt_image || curr_image == image )
4060     curr_image = (Image *) NULL;
4061   if ( curr_image != (Image *) NULL )
4062     curr_image = DestroyImage(curr_image);
4063   if ( work_image != (Image *) NULL )
4064     work_image = DestroyImage(work_image);
4065   if ( save_image != (Image *) NULL )
4066     save_image = DestroyImage(save_image);
4067   if ( reflected_kernel != (KernelInfo *) NULL )
4068     reflected_kernel = DestroyKernelInfo(reflected_kernel);
4069   return(rslt_image);
4070 }
4071 
4072 
4073 /*
4074 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4075 %                                                                             %
4076 %                                                                             %
4077 %                                                                             %
4078 %     M o r p h o l o g y I m a g e                                           %
4079 %                                                                             %
4080 %                                                                             %
4081 %                                                                             %
4082 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4083 %
4084 %  MorphologyImage() applies a user supplied kernel to the image according to
4085 %  the given mophology method.
4086 %
4087 %  This function applies any and all user defined settings before calling
4088 %  the above internal function MorphologyApply().
4089 %
4090 %  User defined settings include...
4091 %    * Output Bias for Convolution and correlation ("-define convolve:bias=??")
4092 %    * Kernel Scale/normalize settings            ("-define convolve:scale=??")
4093 %      This can also includes the addition of a scaled unity kernel.
4094 %    * Show Kernel being applied            ("-define morphology:showKernel=1")
4095 %
4096 %  Other operators that do not want user supplied options interfering,
4097 %  especially "convolve:bias" and "morphology:showKernel" should use
4098 %  MorphologyApply() directly.
4099 %
4100 %  The format of the MorphologyImage method is:
4101 %
4102 %      Image *MorphologyImage(const Image *image,MorphologyMethod method,
4103 %        const ssize_t iterations,KernelInfo *kernel,ExceptionInfo *exception)
4104 %
4105 %  A description of each parameter follows:
4106 %
4107 %    o image: the image.
4108 %
4109 %    o method: the morphology method to be applied.
4110 %
4111 %    o iterations: apply the operation this many times (or no change).
4112 %                  A value of -1 means loop until no change found.
4113 %                  How this is applied may depend on the morphology method.
4114 %                  Typically this is a value of 1.
4115 %
4116 %    o kernel: An array of double representing the morphology kernel.
4117 %              Warning: kernel may be normalized for the Convolve method.
4118 %
4119 %    o exception: return any errors or warnings in this structure.
4120 %
4121 */
MorphologyImage(const Image * image,const MorphologyMethod method,const ssize_t iterations,const KernelInfo * kernel,ExceptionInfo * exception)4122 MagickExport Image *MorphologyImage(const Image *image,
4123   const MorphologyMethod method,const ssize_t iterations,
4124   const KernelInfo *kernel,ExceptionInfo *exception)
4125 {
4126   const char
4127     *artifact;
4128 
4129   CompositeOperator
4130     compose;
4131 
4132   double
4133     bias;
4134 
4135   Image
4136     *morphology_image;
4137 
4138   KernelInfo
4139     *curr_kernel;
4140 
4141   curr_kernel = (KernelInfo *) kernel;
4142   bias=0.0;
4143   compose = UndefinedCompositeOp;  /* use default for method */
4144 
4145   /* Apply Convolve/Correlate Normalization and Scaling Factors.
4146    * This is done BEFORE the ShowKernelInfo() function is called so that
4147    * users can see the results of the 'option:convolve:scale' option.
4148    */
4149   if ( method == ConvolveMorphology || method == CorrelateMorphology ) {
4150       /* Get the bias value as it will be needed */
4151       artifact = GetImageArtifact(image,"convolve:bias");
4152       if ( artifact != (const char *) NULL) {
4153         if (IsGeometry(artifact) == MagickFalse)
4154           (void) ThrowMagickException(exception,GetMagickModule(),
4155                OptionWarning,"InvalidSetting","'%s' '%s'",
4156                "convolve:bias",artifact);
4157         else
4158           bias=StringToDoubleInterval(artifact,(double) QuantumRange+1.0);
4159       }
4160 
4161       /* Scale kernel according to user wishes */
4162       artifact = GetImageArtifact(image,"convolve:scale");
4163       if ( artifact != (const char *) NULL ) {
4164         if (IsGeometry(artifact) == MagickFalse)
4165           (void) ThrowMagickException(exception,GetMagickModule(),
4166                OptionWarning,"InvalidSetting","'%s' '%s'",
4167                "convolve:scale",artifact);
4168         else {
4169           if ( curr_kernel == kernel )
4170             curr_kernel = CloneKernelInfo(kernel);
4171           if (curr_kernel == (KernelInfo *) NULL)
4172             return((Image *) NULL);
4173           ScaleGeometryKernelInfo(curr_kernel, artifact);
4174         }
4175       }
4176     }
4177 
4178   /* display the (normalized) kernel via stderr */
4179   artifact=GetImageArtifact(image,"morphology:showKernel");
4180   if (IsStringTrue(artifact) != MagickFalse)
4181     ShowKernelInfo(curr_kernel);
4182 
4183   /* Override the default handling of multi-kernel morphology results
4184    * If 'Undefined' use the default method
4185    * If 'None' (default for 'Convolve') re-iterate previous result
4186    * Otherwise merge resulting images using compose method given.
4187    * Default for 'HitAndMiss' is 'Lighten'.
4188    */
4189   {
4190     ssize_t
4191       parse;
4192 
4193     artifact = GetImageArtifact(image,"morphology:compose");
4194     if ( artifact != (const char *) NULL) {
4195       parse=ParseCommandOption(MagickComposeOptions,
4196         MagickFalse,artifact);
4197       if ( parse < 0 )
4198         (void) ThrowMagickException(exception,GetMagickModule(),
4199              OptionWarning,"UnrecognizedComposeOperator","'%s' '%s'",
4200              "morphology:compose",artifact);
4201       else
4202         compose=(CompositeOperator)parse;
4203     }
4204   }
4205   /* Apply the Morphology */
4206   morphology_image = MorphologyApply(image,method,iterations,
4207     curr_kernel,compose,bias,exception);
4208 
4209   /* Cleanup and Exit */
4210   if ( curr_kernel != kernel )
4211     curr_kernel=DestroyKernelInfo(curr_kernel);
4212   return(morphology_image);
4213 }
4214 
4215 /*
4216 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4217 %                                                                             %
4218 %                                                                             %
4219 %                                                                             %
4220 +     R o t a t e K e r n e l I n f o                                         %
4221 %                                                                             %
4222 %                                                                             %
4223 %                                                                             %
4224 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4225 %
4226 %  RotateKernelInfo() rotates the kernel by the angle given.
4227 %
4228 %  Currently it is restricted to 90 degree angles, of either 1D kernels
4229 %  or square kernels. And 'circular' rotations of 45 degrees for 3x3 kernels.
4230 %  It will ignore usless rotations for specific 'named' built-in kernels.
4231 %
4232 %  The format of the RotateKernelInfo method is:
4233 %
4234 %      void RotateKernelInfo(KernelInfo *kernel, double angle)
4235 %
4236 %  A description of each parameter follows:
4237 %
4238 %    o kernel: the Morphology/Convolution kernel
4239 %
4240 %    o angle: angle to rotate in degrees
4241 %
4242 % This function is currently internal to this module only, but can be exported
4243 % to other modules if needed.
4244 */
RotateKernelInfo(KernelInfo * kernel,double angle)4245 static void RotateKernelInfo(KernelInfo *kernel, double angle)
4246 {
4247   /* angle the lower kernels first */
4248   if ( kernel->next != (KernelInfo *) NULL)
4249     RotateKernelInfo(kernel->next, angle);
4250 
4251   /* WARNING: Currently assumes the kernel (rightly) is horizontally symetrical
4252   **
4253   ** TODO: expand beyond simple 90 degree rotates, flips and flops
4254   */
4255 
4256   /* Modulus the angle */
4257   angle = fmod(angle, 360.0);
4258   if ( angle < 0 )
4259     angle += 360.0;
4260 
4261   if ( 337.5 < angle || angle <= 22.5 )
4262     return;   /* Near zero angle - no change! - At least not at this time */
4263 
4264   /* Handle special cases */
4265   switch (kernel->type) {
4266     /* These built-in kernels are cylindrical kernels, rotating is useless */
4267     case GaussianKernel:
4268     case DoGKernel:
4269     case LoGKernel:
4270     case DiskKernel:
4271     case PeaksKernel:
4272     case LaplacianKernel:
4273     case ChebyshevKernel:
4274     case ManhattanKernel:
4275     case EuclideanKernel:
4276       return;
4277 
4278     /* These may be rotatable at non-90 angles in the future */
4279     /* but simply rotating them in multiples of 90 degrees is useless */
4280     case SquareKernel:
4281     case DiamondKernel:
4282     case PlusKernel:
4283     case CrossKernel:
4284       return;
4285 
4286     /* These only allows a +/-90 degree rotation (by transpose) */
4287     /* A 180 degree rotation is useless */
4288     case BlurKernel:
4289       if ( 135.0 < angle && angle <= 225.0 )
4290         return;
4291       if ( 225.0 < angle && angle <= 315.0 )
4292         angle -= 180;
4293       break;
4294 
4295     default:
4296       break;
4297   }
4298   /* Attempt rotations by 45 degrees  -- 3x3 kernels only */
4299   if ( 22.5 < fmod(angle,90.0) && fmod(angle,90.0) <= 67.5 )
4300     {
4301       if ( kernel->width == 3 && kernel->height == 3 )
4302         { /* Rotate a 3x3 square by 45 degree angle */
4303           double t  = kernel->values[0];
4304           kernel->values[0] = kernel->values[3];
4305           kernel->values[3] = kernel->values[6];
4306           kernel->values[6] = kernel->values[7];
4307           kernel->values[7] = kernel->values[8];
4308           kernel->values[8] = kernel->values[5];
4309           kernel->values[5] = kernel->values[2];
4310           kernel->values[2] = kernel->values[1];
4311           kernel->values[1] = t;
4312           /* rotate non-centered origin */
4313           if ( kernel->x != 1 || kernel->y != 1 ) {
4314             ssize_t x,y;
4315             x = (ssize_t) kernel->x-1;
4316             y = (ssize_t) kernel->y-1;
4317                  if ( x == y  ) x = 0;
4318             else if ( x == 0  ) x = -y;
4319             else if ( x == -y ) y = 0;
4320             else if ( y == 0  ) y = x;
4321             kernel->x = (ssize_t) x+1;
4322             kernel->y = (ssize_t) y+1;
4323           }
4324           angle = fmod(angle+315.0, 360.0);  /* angle reduced 45 degrees */
4325           kernel->angle = fmod(kernel->angle+45.0, 360.0);
4326         }
4327       else
4328         perror("Unable to rotate non-3x3 kernel by 45 degrees");
4329     }
4330   if ( 45.0 < fmod(angle, 180.0)  && fmod(angle,180.0) <= 135.0 )
4331     {
4332       if ( kernel->width == 1 || kernel->height == 1 )
4333         { /* Do a transpose of a 1 dimensional kernel,
4334           ** which results in a fast 90 degree rotation of some type.
4335           */
4336           ssize_t
4337             t;
4338           t = (ssize_t) kernel->width;
4339           kernel->width = kernel->height;
4340           kernel->height = (size_t) t;
4341           t = kernel->x;
4342           kernel->x = kernel->y;
4343           kernel->y = t;
4344           if ( kernel->width == 1 ) {
4345             angle = fmod(angle+270.0, 360.0);     /* angle reduced 90 degrees */
4346             kernel->angle = fmod(kernel->angle+90.0, 360.0);
4347           } else {
4348             angle = fmod(angle+90.0, 360.0);   /* angle increased 90 degrees */
4349             kernel->angle = fmod(kernel->angle+270.0, 360.0);
4350           }
4351         }
4352       else if ( kernel->width == kernel->height )
4353         { /* Rotate a square array of values by 90 degrees */
4354           { register ssize_t
4355               i,j,x,y;
4356 
4357             register MagickRealType
4358               *k,t;
4359 
4360             k=kernel->values;
4361             for( i=0, x=(ssize_t) kernel->width-1;  i<=x;   i++, x--)
4362               for( j=0, y=(ssize_t) kernel->height-1;  j<y;   j++, y--)
4363                 { t                    = k[i+j*kernel->width];
4364                   k[i+j*kernel->width] = k[j+x*kernel->width];
4365                   k[j+x*kernel->width] = k[x+y*kernel->width];
4366                   k[x+y*kernel->width] = k[y+i*kernel->width];
4367                   k[y+i*kernel->width] = t;
4368                 }
4369           }
4370           /* rotate the origin - relative to center of array */
4371           { register ssize_t x,y;
4372             x = (ssize_t) (kernel->x*2-kernel->width+1);
4373             y = (ssize_t) (kernel->y*2-kernel->height+1);
4374             kernel->x = (ssize_t) ( -y +(ssize_t) kernel->width-1)/2;
4375             kernel->y = (ssize_t) ( +x +(ssize_t) kernel->height-1)/2;
4376           }
4377           angle = fmod(angle+270.0, 360.0);     /* angle reduced 90 degrees */
4378           kernel->angle = fmod(kernel->angle+90.0, 360.0);
4379         }
4380       else
4381         perror("Unable to rotate a non-square, non-linear kernel 90 degrees");
4382     }
4383   if ( 135.0 < angle && angle <= 225.0 )
4384     {
4385       /* For a 180 degree rotation - also know as a reflection
4386        * This is actually a very very common operation!
4387        * Basically all that is needed is a reversal of the kernel data!
4388        * And a reflection of the origon
4389        */
4390       MagickRealType
4391         t;
4392 
4393       register MagickRealType
4394         *k;
4395 
4396       ssize_t
4397         i,
4398         j;
4399 
4400       k=kernel->values;
4401       j=(ssize_t) (kernel->width*kernel->height-1);
4402       for (i=0;  i < j;  i++, j--)
4403         t=k[i],  k[i]=k[j],  k[j]=t;
4404 
4405       kernel->x = (ssize_t) kernel->width  - kernel->x - 1;
4406       kernel->y = (ssize_t) kernel->height - kernel->y - 1;
4407       angle = fmod(angle-180.0, 360.0);   /* angle+180 degrees */
4408       kernel->angle = fmod(kernel->angle+180.0, 360.0);
4409     }
4410   /* At this point angle should at least between -45 (315) and +45 degrees
4411    * In the future some form of non-orthogonal angled rotates could be
4412    * performed here, posibily with a linear kernel restriction.
4413    */
4414 
4415   return;
4416 }
4417 
4418 /*
4419 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4420 %                                                                             %
4421 %                                                                             %
4422 %                                                                             %
4423 %     S c a l e G e o m e t r y K e r n e l I n f o                           %
4424 %                                                                             %
4425 %                                                                             %
4426 %                                                                             %
4427 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4428 %
4429 %  ScaleGeometryKernelInfo() takes a geometry argument string, typically
4430 %  provided as a  "-set option:convolve:scale {geometry}" user setting,
4431 %  and modifies the kernel according to the parsed arguments of that setting.
4432 %
4433 %  The first argument (and any normalization flags) are passed to
4434 %  ScaleKernelInfo() to scale/normalize the kernel.  The second argument
4435 %  is then passed to UnityAddKernelInfo() to add a scled unity kernel
4436 %  into the scaled/normalized kernel.
4437 %
4438 %  The format of the ScaleGeometryKernelInfo method is:
4439 %
4440 %      void ScaleGeometryKernelInfo(KernelInfo *kernel,
4441 %        const double scaling_factor,const MagickStatusType normalize_flags)
4442 %
4443 %  A description of each parameter follows:
4444 %
4445 %    o kernel: the Morphology/Convolution kernel to modify
4446 %
4447 %    o geometry:
4448 %             The geometry string to parse, typically from the user provided
4449 %             "-set option:convolve:scale {geometry}" setting.
4450 %
4451 */
ScaleGeometryKernelInfo(KernelInfo * kernel,const char * geometry)4452 MagickExport void ScaleGeometryKernelInfo (KernelInfo *kernel,
4453   const char *geometry)
4454 {
4455   MagickStatusType
4456     flags;
4457 
4458   GeometryInfo
4459     args;
4460 
4461   SetGeometryInfo(&args);
4462   flags = ParseGeometry(geometry, &args);
4463 
4464 #if 0
4465   /* For Debugging Geometry Input */
4466   (void) FormatLocaleFile(stderr, "Geometry = 0x%04X : %lg x %lg %+lg %+lg\n",
4467        flags, args.rho, args.sigma, args.xi, args.psi );
4468 #endif
4469 
4470   if ( (flags & PercentValue) != 0 )      /* Handle Percentage flag*/
4471     args.rho *= 0.01,  args.sigma *= 0.01;
4472 
4473   if ( (flags & RhoValue) == 0 )          /* Set Defaults for missing args */
4474     args.rho = 1.0;
4475   if ( (flags & SigmaValue) == 0 )
4476     args.sigma = 0.0;
4477 
4478   /* Scale/Normalize the input kernel */
4479   ScaleKernelInfo(kernel, args.rho, (GeometryFlags) flags);
4480 
4481   /* Add Unity Kernel, for blending with original */
4482   if ( (flags & SigmaValue) != 0 )
4483     UnityAddKernelInfo(kernel, args.sigma);
4484 
4485   return;
4486 }
4487 /*
4488 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4489 %                                                                             %
4490 %                                                                             %
4491 %                                                                             %
4492 %     S c a l e K e r n e l I n f o                                           %
4493 %                                                                             %
4494 %                                                                             %
4495 %                                                                             %
4496 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4497 %
4498 %  ScaleKernelInfo() scales the given kernel list by the given amount, with or
4499 %  without normalization of the sum of the kernel values (as per given flags).
4500 %
4501 %  By default (no flags given) the values within the kernel is scaled
4502 %  directly using given scaling factor without change.
4503 %
4504 %  If either of the two 'normalize_flags' are given the kernel will first be
4505 %  normalized and then further scaled by the scaling factor value given.
4506 %
4507 %  Kernel normalization ('normalize_flags' given) is designed to ensure that
4508 %  any use of the kernel scaling factor with 'Convolve' or 'Correlate'
4509 %  morphology methods will fall into -1.0 to +1.0 range.  Note that for
4510 %  non-HDRI versions of IM this may cause images to have any negative results
4511 %  clipped, unless some 'bias' is used.
4512 %
4513 %  More specifically.  Kernels which only contain positive values (such as a
4514 %  'Gaussian' kernel) will be scaled so that those values sum to +1.0,
4515 %  ensuring a 0.0 to +1.0 output range for non-HDRI images.
4516 %
4517 %  For Kernels that contain some negative values, (such as 'Sharpen' kernels)
4518 %  the kernel will be scaled by the absolute of the sum of kernel values, so
4519 %  that it will generally fall within the +/- 1.0 range.
4520 %
4521 %  For kernels whose values sum to zero, (such as 'Laplician' kernels) kernel
4522 %  will be scaled by just the sum of the postive values, so that its output
4523 %  range will again fall into the  +/- 1.0 range.
4524 %
4525 %  For special kernels designed for locating shapes using 'Correlate', (often
4526 %  only containing +1 and -1 values, representing foreground/brackground
4527 %  matching) a special normalization method is provided to scale the positive
4528 %  values separately to those of the negative values, so the kernel will be
4529 %  forced to become a zero-sum kernel better suited to such searches.
4530 %
4531 %  WARNING: Correct normalization of the kernel assumes that the '*_range'
4532 %  attributes within the kernel structure have been correctly set during the
4533 %  kernels creation.
4534 %
4535 %  NOTE: The values used for 'normalize_flags' have been selected specifically
4536 %  to match the use of geometry options, so that '!' means NormalizeValue, '^'
4537 %  means CorrelateNormalizeValue.  All other GeometryFlags values are ignored.
4538 %
4539 %  The format of the ScaleKernelInfo method is:
4540 %
4541 %      void ScaleKernelInfo(KernelInfo *kernel, const double scaling_factor,
4542 %               const MagickStatusType normalize_flags )
4543 %
4544 %  A description of each parameter follows:
4545 %
4546 %    o kernel: the Morphology/Convolution kernel
4547 %
4548 %    o scaling_factor:
4549 %             multiply all values (after normalization) by this factor if not
4550 %             zero.  If the kernel is normalized regardless of any flags.
4551 %
4552 %    o normalize_flags:
4553 %             GeometryFlags defining normalization method to use.
4554 %             specifically: NormalizeValue, CorrelateNormalizeValue,
4555 %                           and/or PercentValue
4556 %
4557 */
ScaleKernelInfo(KernelInfo * kernel,const double scaling_factor,const GeometryFlags normalize_flags)4558 MagickExport void ScaleKernelInfo(KernelInfo *kernel,
4559   const double scaling_factor,const GeometryFlags normalize_flags)
4560 {
4561   register double
4562     pos_scale,
4563     neg_scale;
4564 
4565   register ssize_t
4566     i;
4567 
4568   /* do the other kernels in a multi-kernel list first */
4569   if ( kernel->next != (KernelInfo *) NULL)
4570     ScaleKernelInfo(kernel->next, scaling_factor, normalize_flags);
4571 
4572   /* Normalization of Kernel */
4573   pos_scale = 1.0;
4574   if ( (normalize_flags&NormalizeValue) != 0 ) {
4575     if ( fabs(kernel->positive_range + kernel->negative_range) >= MagickEpsilon )
4576       /* non-zero-summing kernel (generally positive) */
4577       pos_scale = fabs(kernel->positive_range + kernel->negative_range);
4578     else
4579       /* zero-summing kernel */
4580       pos_scale = kernel->positive_range;
4581   }
4582   /* Force kernel into a normalized zero-summing kernel */
4583   if ( (normalize_flags&CorrelateNormalizeValue) != 0 ) {
4584     pos_scale = ( fabs(kernel->positive_range) >= MagickEpsilon )
4585                  ? kernel->positive_range : 1.0;
4586     neg_scale = ( fabs(kernel->negative_range) >= MagickEpsilon )
4587                  ? -kernel->negative_range : 1.0;
4588   }
4589   else
4590     neg_scale = pos_scale;
4591 
4592   /* finialize scaling_factor for positive and negative components */
4593   pos_scale = scaling_factor/pos_scale;
4594   neg_scale = scaling_factor/neg_scale;
4595 
4596   for (i=0; i < (ssize_t) (kernel->width*kernel->height); i++)
4597     if (!IsNaN(kernel->values[i]))
4598       kernel->values[i] *= (kernel->values[i] >= 0) ? pos_scale : neg_scale;
4599 
4600   /* convolution output range */
4601   kernel->positive_range *= pos_scale;
4602   kernel->negative_range *= neg_scale;
4603   /* maximum and minimum values in kernel */
4604   kernel->maximum *= (kernel->maximum >= 0.0) ? pos_scale : neg_scale;
4605   kernel->minimum *= (kernel->minimum >= 0.0) ? pos_scale : neg_scale;
4606 
4607   /* swap kernel settings if user's scaling factor is negative */
4608   if ( scaling_factor < MagickEpsilon ) {
4609     double t;
4610     t = kernel->positive_range;
4611     kernel->positive_range = kernel->negative_range;
4612     kernel->negative_range = t;
4613     t = kernel->maximum;
4614     kernel->maximum = kernel->minimum;
4615     kernel->minimum = 1;
4616   }
4617 
4618   return;
4619 }
4620 
4621 /*
4622 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4623 %                                                                             %
4624 %                                                                             %
4625 %                                                                             %
4626 %     S h o w K e r n e l I n f o                                             %
4627 %                                                                             %
4628 %                                                                             %
4629 %                                                                             %
4630 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4631 %
4632 %  ShowKernelInfo() outputs the details of the given kernel defination to
4633 %  standard error, generally due to a users 'morphology:showKernel' option
4634 %  request.
4635 %
4636 %  The format of the ShowKernel method is:
4637 %
4638 %      void ShowKernelInfo(const KernelInfo *kernel)
4639 %
4640 %  A description of each parameter follows:
4641 %
4642 %    o kernel: the Morphology/Convolution kernel
4643 %
4644 */
ShowKernelInfo(const KernelInfo * kernel)4645 MagickPrivate void ShowKernelInfo(const KernelInfo *kernel)
4646 {
4647   const KernelInfo
4648     *k;
4649 
4650   size_t
4651     c, i, u, v;
4652 
4653   for (c=0, k=kernel;  k != (KernelInfo *) NULL;  c++, k=k->next ) {
4654 
4655     (void) FormatLocaleFile(stderr, "Kernel");
4656     if ( kernel->next != (KernelInfo *) NULL )
4657       (void) FormatLocaleFile(stderr, " #%lu", (unsigned long) c );
4658     (void) FormatLocaleFile(stderr, " \"%s",
4659           CommandOptionToMnemonic(MagickKernelOptions, k->type) );
4660     if ( fabs(k->angle) >= MagickEpsilon )
4661       (void) FormatLocaleFile(stderr, "@%lg", k->angle);
4662     (void) FormatLocaleFile(stderr, "\" of size %lux%lu%+ld%+ld",(unsigned long)
4663       k->width,(unsigned long) k->height,(long) k->x,(long) k->y);
4664     (void) FormatLocaleFile(stderr,
4665           " with values from %.*lg to %.*lg\n",
4666           GetMagickPrecision(), k->minimum,
4667           GetMagickPrecision(), k->maximum);
4668     (void) FormatLocaleFile(stderr, "Forming a output range from %.*lg to %.*lg",
4669           GetMagickPrecision(), k->negative_range,
4670           GetMagickPrecision(), k->positive_range);
4671     if ( fabs(k->positive_range+k->negative_range) < MagickEpsilon )
4672       (void) FormatLocaleFile(stderr, " (Zero-Summing)\n");
4673     else if ( fabs(k->positive_range+k->negative_range-1.0) < MagickEpsilon )
4674       (void) FormatLocaleFile(stderr, " (Normalized)\n");
4675     else
4676       (void) FormatLocaleFile(stderr, " (Sum %.*lg)\n",
4677           GetMagickPrecision(), k->positive_range+k->negative_range);
4678     for (i=v=0; v < k->height; v++) {
4679       (void) FormatLocaleFile(stderr, "%2lu:", (unsigned long) v );
4680       for (u=0; u < k->width; u++, i++)
4681         if (IsNaN(k->values[i]))
4682           (void) FormatLocaleFile(stderr," %*s", GetMagickPrecision()+3, "nan");
4683         else
4684           (void) FormatLocaleFile(stderr," %*.*lg", GetMagickPrecision()+3,
4685               GetMagickPrecision(), (double) k->values[i]);
4686       (void) FormatLocaleFile(stderr,"\n");
4687     }
4688   }
4689 }
4690 
4691 /*
4692 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4693 %                                                                             %
4694 %                                                                             %
4695 %                                                                             %
4696 %     U n i t y A d d K e r n a l I n f o                                     %
4697 %                                                                             %
4698 %                                                                             %
4699 %                                                                             %
4700 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4701 %
4702 %  UnityAddKernelInfo() Adds a given amount of the 'Unity' Convolution Kernel
4703 %  to the given pre-scaled and normalized Kernel.  This in effect adds that
4704 %  amount of the original image into the resulting convolution kernel.  This
4705 %  value is usually provided by the user as a percentage value in the
4706 %  'convolve:scale' setting.
4707 %
4708 %  The resulting effect is to convert the defined kernels into blended
4709 %  soft-blurs, unsharp kernels or into sharpening kernels.
4710 %
4711 %  The format of the UnityAdditionKernelInfo method is:
4712 %
4713 %      void UnityAdditionKernelInfo(KernelInfo *kernel, const double scale )
4714 %
4715 %  A description of each parameter follows:
4716 %
4717 %    o kernel: the Morphology/Convolution kernel
4718 %
4719 %    o scale:
4720 %             scaling factor for the unity kernel to be added to
4721 %             the given kernel.
4722 %
4723 */
UnityAddKernelInfo(KernelInfo * kernel,const double scale)4724 MagickExport void UnityAddKernelInfo(KernelInfo *kernel,
4725   const double scale)
4726 {
4727   /* do the other kernels in a multi-kernel list first */
4728   if ( kernel->next != (KernelInfo *) NULL)
4729     UnityAddKernelInfo(kernel->next, scale);
4730 
4731   /* Add the scaled unity kernel to the existing kernel */
4732   kernel->values[kernel->x+kernel->y*kernel->width] += scale;
4733   CalcKernelMetaData(kernel);  /* recalculate the meta-data */
4734 
4735   return;
4736 }
4737 
4738 /*
4739 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4740 %                                                                             %
4741 %                                                                             %
4742 %                                                                             %
4743 %     Z e r o K e r n e l N a n s                                             %
4744 %                                                                             %
4745 %                                                                             %
4746 %                                                                             %
4747 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4748 %
4749 %  ZeroKernelNans() replaces any special 'nan' value that may be present in
4750 %  the kernel with a zero value.  This is typically done when the kernel will
4751 %  be used in special hardware (GPU) convolution processors, to simply
4752 %  matters.
4753 %
4754 %  The format of the ZeroKernelNans method is:
4755 %
4756 %      void ZeroKernelNans (KernelInfo *kernel)
4757 %
4758 %  A description of each parameter follows:
4759 %
4760 %    o kernel: the Morphology/Convolution kernel
4761 %
4762 */
ZeroKernelNans(KernelInfo * kernel)4763 MagickPrivate void ZeroKernelNans(KernelInfo *kernel)
4764 {
4765   register size_t
4766     i;
4767 
4768   /* do the other kernels in a multi-kernel list first */
4769   if (kernel->next != (KernelInfo *) NULL)
4770     ZeroKernelNans(kernel->next);
4771 
4772   for (i=0; i < (kernel->width*kernel->height); i++)
4773     if (IsNaN(kernel->values[i]))
4774       kernel->values[i]=0.0;
4775 
4776   return;
4777 }
4778