MagickCore  7.0.3
resize.c
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1 /*
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13 % MagickCore Image Resize Methods %
14 % %
15 % Software Design %
16 % Cristy %
17 % July 1992 %
18 % %
19 % %
20 % Copyright 1999-2019 ImageMagick Studio LLC, a non-profit organization %
21 % dedicated to making software imaging solutions freely available. %
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23 % You may not use this file except in compliance with the License. You may %
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34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
35 %
36 %
37 */
38 
39 /*
40  Include declarations.
41 */
42 #include "MagickCore/studio.h"
44 #include "MagickCore/artifact.h"
45 #include "MagickCore/blob.h"
46 #include "MagickCore/cache.h"
47 #include "MagickCore/cache-view.h"
48 #include "MagickCore/channel.h"
49 #include "MagickCore/color.h"
51 #include "MagickCore/draw.h"
52 #include "MagickCore/exception.h"
54 #include "MagickCore/gem.h"
55 #include "MagickCore/image.h"
57 #include "MagickCore/list.h"
58 #include "MagickCore/memory_.h"
60 #include "MagickCore/magick.h"
62 #include "MagickCore/property.h"
63 #include "MagickCore/monitor.h"
66 #include "MagickCore/option.h"
67 #include "MagickCore/pixel.h"
70 #include "MagickCore/resample.h"
72 #include "MagickCore/resize.h"
74 #include "MagickCore/resource_.h"
75 #include "MagickCore/string_.h"
78 #include "MagickCore/token.h"
79 #include "MagickCore/utility.h"
81 #include "MagickCore/version.h"
82 #if defined(MAGICKCORE_LQR_DELEGATE)
83 #include <lqr.h>
84 #endif
85 
86 /*
87  Typedef declarations.
88 */
90 {
91  double
92  (*filter)(const double,const ResizeFilter *),
93  (*window)(const double,const ResizeFilter *),
94  support, /* filter region of support - the filter support limit */
95  window_support, /* window support, usally equal to support (expert only) */
96  scale, /* dimension scaling to fit window support (usally 1.0) */
97  blur, /* x-scale (blur-sharpen) */
98  coefficient[7]; /* cubic coefficents for BC-cubic filters */
99 
103 
104  size_t
106 };
107 
108 /*
109  Forward declaractions.
110 */
111 static double
112  I0(double x),
113  BesselOrderOne(double),
114  Sinc(const double, const ResizeFilter *),
115  SincFast(const double, const ResizeFilter *);
116 
117 /*
118 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
119 % %
120 % %
121 % %
122 + F i l t e r F u n c t i o n s %
123 % %
124 % %
125 % %
126 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
127 %
128 % These are the various filter and windowing functions that are provided.
129 %
130 % They are internal to this module only. See AcquireResizeFilterInfo() for
131 % details of the access to these functions, via the GetResizeFilterSupport()
132 % and GetResizeFilterWeight() API interface.
133 %
134 % The individual filter functions have this format...
135 %
136 % static MagickRealtype *FilterName(const double x,const double support)
137 %
138 % A description of each parameter follows:
139 %
140 % o x: the distance from the sampling point generally in the range of 0 to
141 % support. The GetResizeFilterWeight() ensures this a positive value.
142 %
143 % o resize_filter: current filter information. This allows function to
144 % access support, and possibly other pre-calculated information defining
145 % the functions.
146 %
147 */
148 
149 static double Blackman(const double x,
150  const ResizeFilter *magick_unused(resize_filter))
151 {
152  /*
153  Blackman: 2nd order cosine windowing function:
154  0.42 + 0.5 cos(pi x) + 0.08 cos(2pi x)
155 
156  Refactored by Chantal Racette and Nicolas Robidoux to one trig call and
157  five flops.
158  */
159  const double cosine = cos((double) (MagickPI*x));
160  magick_unreferenced(resize_filter);
161  return(0.34+cosine*(0.5+cosine*0.16));
162 }
163 
164 static double Bohman(const double x,
165  const ResizeFilter *magick_unused(resize_filter))
166 {
167  /*
168  Bohman: 2rd Order cosine windowing function:
169  (1-x) cos(pi x) + sin(pi x) / pi.
170 
171  Refactored by Nicolas Robidoux to one trig call, one sqrt call, and 7 flops,
172  taking advantage of the fact that the support of Bohman is 1.0 (so that we
173  know that sin(pi x) >= 0).
174  */
175  const double cosine = cos((double) (MagickPI*x));
176  const double sine=sqrt(1.0-cosine*cosine);
177  magick_unreferenced(resize_filter);
178  return((1.0-x)*cosine+(1.0/MagickPI)*sine);
179 }
180 
181 static double Box(const double magick_unused(x),
182  const ResizeFilter *magick_unused(resize_filter))
183 {
185  magick_unreferenced(resize_filter);
186 
187  /*
188  A Box filter is a equal weighting function (all weights equal).
189  DO NOT LIMIT results by support or resize point sampling will work
190  as it requests points beyond its normal 0.0 support size.
191  */
192  return(1.0);
193 }
194 
195 static double Cosine(const double x,
196  const ResizeFilter *magick_unused(resize_filter))
197 {
198  magick_unreferenced(resize_filter);
199 
200  /*
201  Cosine window function:
202  cos((pi/2)*x).
203  */
204  return(cos((double) (MagickPI2*x)));
205 }
206 
207 static double CubicBC(const double x,const ResizeFilter *resize_filter)
208 {
209  /*
210  Cubic Filters using B,C determined values:
211  Mitchell-Netravali B = 1/3 C = 1/3 "Balanced" cubic spline filter
212  Catmull-Rom B = 0 C = 1/2 Interpolatory and exact on linears
213  Spline B = 1 C = 0 B-Spline Gaussian approximation
214  Hermite B = 0 C = 0 B-Spline interpolator
215 
216  See paper by Mitchell and Netravali, Reconstruction Filters in Computer
217  Graphics Computer Graphics, Volume 22, Number 4, August 1988
218  http://www.cs.utexas.edu/users/fussell/courses/cs384g/lectures/mitchell/
219  Mitchell.pdf.
220 
221  Coefficents are determined from B,C values:
222  P0 = ( 6 - 2*B )/6 = coeff[0]
223  P1 = 0
224  P2 = (-18 +12*B + 6*C )/6 = coeff[1]
225  P3 = ( 12 - 9*B - 6*C )/6 = coeff[2]
226  Q0 = ( 8*B +24*C )/6 = coeff[3]
227  Q1 = ( -12*B -48*C )/6 = coeff[4]
228  Q2 = ( 6*B +30*C )/6 = coeff[5]
229  Q3 = ( - 1*B - 6*C )/6 = coeff[6]
230 
231  which are used to define the filter:
232 
233  P0 + P1*x + P2*x^2 + P3*x^3 0 <= x < 1
234  Q0 + Q1*x + Q2*x^2 + Q3*x^3 1 <= x < 2
235 
236  which ensures function is continuous in value and derivative (slope).
237  */
238  if (x < 1.0)
239  return(resize_filter->coefficient[0]+x*(x*
240  (resize_filter->coefficient[1]+x*resize_filter->coefficient[2])));
241  if (x < 2.0)
242  return(resize_filter->coefficient[3]+x*(resize_filter->coefficient[4]+x*
243  (resize_filter->coefficient[5]+x*resize_filter->coefficient[6])));
244  return(0.0);
245 }
246 
247 static double CubicSpline(const double x,const ResizeFilter *resize_filter)
248 {
249  if (resize_filter->support <= 2.0)
250  {
251  /*
252  2-lobe Spline filter.
253  */
254  if (x < 1.0)
255  return(((x-9.0/5.0)*x-1.0/5.0)*x+1.0);
256  if (x < 2.0)
257  return(((-1.0/3.0*(x-1.0)+4.0/5.0)*(x-1.0)-7.0/15.0)*(x-1.0));
258  return(0.0);
259  }
260  if (resize_filter->support <= 3.0)
261  {
262  /*
263  3-lobe Spline filter.
264  */
265  if (x < 1.0)
266  return(((13.0/11.0*x-453.0/209.0)*x-3.0/209.0)*x+1.0);
267  if (x < 2.0)
268  return(((-6.0/11.0*(x-1.0)+270.0/209.0)*(x-1.0)-156.0/209.0)*(x-1.0));
269  if (x < 3.0)
270  return(((1.0/11.0*(x-2.0)-45.0/209.0)*(x-2.0)+26.0/209.0)*(x-2.0));
271  return(0.0);
272  }
273  /*
274  4-lobe Spline filter.
275  */
276  if (x < 1.0)
277  return(((49.0/41.0*x-6387.0/2911.0)*x-3.0/2911.0)*x+1.0);
278  if (x < 2.0)
279  return(((-24.0/41.0*(x-1.0)+4032.0/2911.0)*(x-1.0)-2328.0/2911.0)*(x-1.0));
280  if (x < 3.0)
281  return(((6.0/41.0*(x-2.0)-1008.0/2911.0)*(x-2.0)+582.0/2911.0)*(x-2.0));
282  if (x < 4.0)
283  return(((-1.0/41.0*(x-3.0)+168.0/2911.0)*(x-3.0)-97.0/2911.0)*(x-3.0));
284  return(0.0);
285 }
286 
287 static double Gaussian(const double x,const ResizeFilter *resize_filter)
288 {
289  /*
290  Gaussian with a sigma = 1/2 (or as user specified)
291 
292  Gaussian Formula (1D) ...
293  exp( -(x^2)/((2.0*sigma^2) ) / (sqrt(2*PI)*sigma^2))
294 
295  Gaussian Formula (2D) ...
296  exp( -(x^2+y^2)/(2.0*sigma^2) ) / (PI*sigma^2) )
297  or for radius
298  exp( -(r^2)/(2.0*sigma^2) ) / (PI*sigma^2) )
299 
300  Note that it is only a change from 1-d to radial form is in the
301  normalization multiplier which is not needed or used when Gaussian is used
302  as a filter.
303 
304  The constants are pre-calculated...
305 
306  coeff[0]=sigma;
307  coeff[1]=1.0/(2.0*sigma^2);
308  coeff[2]=1.0/(sqrt(2*PI)*sigma^2);
309 
310  exp( -coeff[1]*(x^2)) ) * coeff[2];
311 
312  However the multiplier coeff[1] is need, the others are informative only.
313 
314  This separates the gaussian 'sigma' value from the 'blur/support'
315  settings allowing for its use in special 'small sigma' gaussians,
316  without the filter 'missing' pixels because the support becomes too
317  small.
318  */
319  return(exp((double)(-resize_filter->coefficient[1]*x*x)));
320 }
321 
322 static double Hann(const double x,
323  const ResizeFilter *magick_unused(resize_filter))
324 {
325  /*
326  Cosine window function:
327  0.5+0.5*cos(pi*x).
328  */
329  const double cosine = cos((double) (MagickPI*x));
330  magick_unreferenced(resize_filter);
331  return(0.5+0.5*cosine);
332 }
333 
334 static double Hamming(const double x,
335  const ResizeFilter *magick_unused(resize_filter))
336 {
337  /*
338  Offset cosine window function:
339  .54 + .46 cos(pi x).
340  */
341  const double cosine = cos((double) (MagickPI*x));
342  magick_unreferenced(resize_filter);
343  return(0.54+0.46*cosine);
344 }
345 
346 static double Jinc(const double x,
347  const ResizeFilter *magick_unused(resize_filter))
348 {
349  magick_unreferenced(resize_filter);
350 
351  /*
352  See Pratt "Digital Image Processing" p.97 for Jinc/Bessel functions.
353  http://mathworld.wolfram.com/JincFunction.html and page 11 of
354  http://www.ph.ed.ac.uk/%7ewjh/teaching/mo/slides/lens/lens.pdf
355 
356  The original "zoom" program by Paul Heckbert called this "Bessel". But
357  really it is more accurately named "Jinc".
358  */
359  if (x == 0.0)
360  return(0.5*MagickPI);
361  return(BesselOrderOne(MagickPI*x)/x);
362 }
363 
364 static double Kaiser(const double x,const ResizeFilter *resize_filter)
365 {
366  /*
367  Kaiser Windowing Function (bessel windowing)
368 
369  I0( beta * sqrt( 1-x^2) ) / IO(0)
370 
371  Beta (coeff[0]) is a free value from 5 to 8 (defaults to 6.5).
372  However it is typically defined in terms of Alpha*PI
373 
374  The normalization factor (coeff[1]) is not actually needed,
375  but without it the filters has a large value at x=0 making it
376  difficult to compare the function with other windowing functions.
377  */
378  return(resize_filter->coefficient[1]*I0(resize_filter->coefficient[0]*
379  sqrt((double) (1.0-x*x))));
380 }
381 
382 static double Lagrange(const double x,const ResizeFilter *resize_filter)
383 {
384  double
385  value;
386 
387  register ssize_t
388  i;
389 
390  ssize_t
391  n,
392  order;
393 
394  /*
395  Lagrange piecewise polynomial fit of sinc: N is the 'order' of the lagrange
396  function and depends on the overall support window size of the filter. That
397  is: for a support of 2, it gives a lagrange-4 (piecewise cubic function).
398 
399  "n" identifies the piece of the piecewise polynomial.
400 
401  See Survey: Interpolation Methods, IEEE Transactions on Medical Imaging,
402  Vol 18, No 11, November 1999, p1049-1075, -- Equation 27 on p1064.
403  */
404  if (x > resize_filter->support)
405  return(0.0);
406  order=(ssize_t) (2.0*resize_filter->window_support); /* number of pieces */
407  n=(ssize_t) (resize_filter->window_support+x);
408  value=1.0f;
409  for (i=0; i < order; i++)
410  if (i != n)
411  value*=(n-i-x)/(n-i);
412  return(value);
413 }
414 
415 static double Quadratic(const double x,
416  const ResizeFilter *magick_unused(resize_filter))
417 {
418  magick_unreferenced(resize_filter);
419 
420  /*
421  2rd order (quadratic) B-Spline approximation of Gaussian.
422  */
423  if (x < 0.5)
424  return(0.75-x*x);
425  if (x < 1.5)
426  return(0.5*(x-1.5)*(x-1.5));
427  return(0.0);
428 }
429 
430 static double Sinc(const double x,
431  const ResizeFilter *magick_unused(resize_filter))
432 {
433  magick_unreferenced(resize_filter);
434 
435  /*
436  Scaled sinc(x) function using a trig call:
437  sinc(x) == sin(pi x)/(pi x).
438  */
439  if (x != 0.0)
440  {
441  const double alpha=(double) (MagickPI*x);
442  return(sin((double) alpha)/alpha);
443  }
444  return((double) 1.0);
445 }
446 
447 static double SincFast(const double x,
448  const ResizeFilter *magick_unused(resize_filter))
449 {
450  magick_unreferenced(resize_filter);
451 
452  /*
453  Approximations of the sinc function sin(pi x)/(pi x) over the interval
454  [-4,4] constructed by Nicolas Robidoux and Chantal Racette with funding
455  from the Natural Sciences and Engineering Research Council of Canada.
456 
457  Although the approximations are polynomials (for low order of
458  approximation) and quotients of polynomials (for higher order of
459  approximation) and consequently are similar in form to Taylor polynomials /
460  Pade approximants, the approximations are computed with a completely
461  different technique.
462 
463  Summary: These approximations are "the best" in terms of bang (accuracy)
464  for the buck (flops). More specifically: Among the polynomial quotients
465  that can be computed using a fixed number of flops (with a given "+ - * /
466  budget"), the chosen polynomial quotient is the one closest to the
467  approximated function with respect to maximum absolute relative error over
468  the given interval.
469 
470  The Remez algorithm, as implemented in the boost library's minimax package,
471  is the key to the construction: http://www.boost.org/doc/libs/1_36_0/libs/
472  math/doc/sf_and_dist/html/math_toolkit/backgrounders/remez.html
473 
474  If outside of the interval of approximation, use the standard trig formula.
475  */
476  if (x > 4.0)
477  {
478  const double alpha=(double) (MagickPI*x);
479  return(sin((double) alpha)/alpha);
480  }
481  {
482  /*
483  The approximations only depend on x^2 (sinc is an even function).
484  */
485  const double xx = x*x;
486 #if MAGICKCORE_QUANTUM_DEPTH <= 8
487  /*
488  Maximum absolute relative error 6.3e-6 < 1/2^17.
489  */
490  const double c0 = 0.173610016489197553621906385078711564924e-2L;
491  const double c1 = -0.384186115075660162081071290162149315834e-3L;
492  const double c2 = 0.393684603287860108352720146121813443561e-4L;
493  const double c3 = -0.248947210682259168029030370205389323899e-5L;
494  const double c4 = 0.107791837839662283066379987646635416692e-6L;
495  const double c5 = -0.324874073895735800961260474028013982211e-8L;
496  const double c6 = 0.628155216606695311524920882748052490116e-10L;
497  const double c7 = -0.586110644039348333520104379959307242711e-12L;
498  const double p =
499  c0+xx*(c1+xx*(c2+xx*(c3+xx*(c4+xx*(c5+xx*(c6+xx*c7))))));
500  return((xx-1.0)*(xx-4.0)*(xx-9.0)*(xx-16.0)*p);
501 #elif MAGICKCORE_QUANTUM_DEPTH <= 16
502  /*
503  Max. abs. rel. error 2.2e-8 < 1/2^25.
504  */
505  const double c0 = 0.173611107357320220183368594093166520811e-2L;
506  const double c1 = -0.384240921114946632192116762889211361285e-3L;
507  const double c2 = 0.394201182359318128221229891724947048771e-4L;
508  const double c3 = -0.250963301609117217660068889165550534856e-5L;
509  const double c4 = 0.111902032818095784414237782071368805120e-6L;
510  const double c5 = -0.372895101408779549368465614321137048875e-8L;
511  const double c6 = 0.957694196677572570319816780188718518330e-10L;
512  const double c7 = -0.187208577776590710853865174371617338991e-11L;
513  const double c8 = 0.253524321426864752676094495396308636823e-13L;
514  const double c9 = -0.177084805010701112639035485248501049364e-15L;
515  const double p =
516  c0+xx*(c1+xx*(c2+xx*(c3+xx*(c4+xx*(c5+xx*(c6+xx*(c7+xx*(c8+xx*c9))))))));
517  return((xx-1.0)*(xx-4.0)*(xx-9.0)*(xx-16.0)*p);
518 #else
519  /*
520  Max. abs. rel. error 1.2e-12 < 1/2^39.
521  */
522  const double c0 = 0.173611111110910715186413700076827593074e-2L;
523  const double c1 = -0.289105544717893415815859968653611245425e-3L;
524  const double c2 = 0.206952161241815727624413291940849294025e-4L;
525  const double c3 = -0.834446180169727178193268528095341741698e-6L;
526  const double c4 = 0.207010104171026718629622453275917944941e-7L;
527  const double c5 = -0.319724784938507108101517564300855542655e-9L;
528  const double c6 = 0.288101675249103266147006509214934493930e-11L;
529  const double c7 = -0.118218971804934245819960233886876537953e-13L;
530  const double p =
531  c0+xx*(c1+xx*(c2+xx*(c3+xx*(c4+xx*(c5+xx*(c6+xx*c7))))));
532  const double d0 = 1.0L;
533  const double d1 = 0.547981619622284827495856984100563583948e-1L;
534  const double d2 = 0.134226268835357312626304688047086921806e-2L;
535  const double d3 = 0.178994697503371051002463656833597608689e-4L;
536  const double d4 = 0.114633394140438168641246022557689759090e-6L;
537  const double q = d0+xx*(d1+xx*(d2+xx*(d3+xx*d4)));
538  return((xx-1.0)*(xx-4.0)*(xx-9.0)*(xx-16.0)/q*p);
539 #endif
540  }
541 }
542 
543 static double Triangle(const double x,
544  const ResizeFilter *magick_unused(resize_filter))
545 {
546  magick_unreferenced(resize_filter);
547 
548  /*
549  1st order (linear) B-Spline, bilinear interpolation, Tent 1D filter, or
550  a Bartlett 2D Cone filter. Also used as a Bartlett Windowing function
551  for Sinc().
552  */
553  if (x < 1.0)
554  return(1.0-x);
555  return(0.0);
556 }
557 
558 static double Welch(const double x,
559  const ResizeFilter *magick_unused(resize_filter))
560 {
561  magick_unreferenced(resize_filter);
562 
563  /*
564  Welch parabolic windowing filter.
565  */
566  if (x < 1.0)
567  return(1.0-x*x);
568  return(0.0);
569 }
570 
571 /*
572 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
573 % %
574 % %
575 % %
576 + A c q u i r e R e s i z e F i l t e r %
577 % %
578 % %
579 % %
580 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
581 %
582 % AcquireResizeFilter() allocates the ResizeFilter structure. Choose from
583 % these filters:
584 %
585 % FIR (Finite impulse Response) Filters
586 % Box Triangle Quadratic
587 % Spline Hermite Catrom
588 % Mitchell
589 %
590 % IIR (Infinite impulse Response) Filters
591 % Gaussian Sinc Jinc (Bessel)
592 %
593 % Windowed Sinc/Jinc Filters
594 % Blackman Bohman Lanczos
595 % Hann Hamming Cosine
596 % Kaiser Welch Parzen
597 % Bartlett
598 %
599 % Special Purpose Filters
600 % Cubic SincFast LanczosSharp Lanczos2 Lanczos2Sharp
601 % Robidoux RobidouxSharp
602 %
603 % The users "-filter" selection is used to lookup the default 'expert'
604 % settings for that filter from a internal table. However any provided
605 % 'expert' settings (see below) may override this selection.
606 %
607 % FIR filters are used as is, and are limited to that filters support window
608 % (unless over-ridden). 'Gaussian' while classed as an IIR filter, is also
609 % simply clipped by its support size (currently 1.5 or approximately 3*sigma
610 % as recommended by many references)
611 %
612 % The special a 'cylindrical' filter flag will promote the default 4-lobed
613 % Windowed Sinc filter to a 3-lobed Windowed Jinc equivalent, which is better
614 % suited to this style of image resampling. This typically happens when using
615 % such a filter for images distortions.
616 %
617 % SPECIFIC FILTERS:
618 %
619 % Directly requesting 'Sinc', 'Jinc' function as a filter will force the use
620 % of function without any windowing, or promotion for cylindrical usage. This
621 % is not recommended, except by image processing experts, especially as part
622 % of expert option filter function selection.
623 %
624 % Two forms of the 'Sinc' function are available: Sinc and SincFast. Sinc is
625 % computed using the traditional sin(pi*x)/(pi*x); it is selected if the user
626 % specifically specifies the use of a Sinc filter. SincFast uses highly
627 % accurate (and fast) polynomial (low Q) and rational (high Q) approximations,
628 % and will be used by default in most cases.
629 %
630 % The Lanczos filter is a special 3-lobed Sinc-windowed Sinc filter (promoted
631 % to Jinc-windowed Jinc for cylindrical (Elliptical Weighted Average) use).
632 % The Sinc version is the most popular windowed filter.
633 %
634 % LanczosSharp is a slightly sharpened (blur=0.9812505644269356 < 1) form of
635 % the Lanczos filter, specifically designed for EWA distortion (as a
636 % Jinc-Jinc); it can also be used as a slightly sharper orthogonal Lanczos
637 % (Sinc-Sinc) filter. The chosen blur value comes as close as possible to
638 % satisfying the following condition without changing the character of the
639 % corresponding EWA filter:
640 %
641 % 'No-Op' Vertical and Horizontal Line Preservation Condition: Images with
642 % only vertical or horizontal features are preserved when performing 'no-op"
643 % with EWA distortion.
644 %
645 % The Lanczos2 and Lanczos2Sharp filters are 2-lobe versions of the Lanczos
646 % filters. The 'sharp' version uses a blur factor of 0.9549963639785485,
647 % again chosen because the resulting EWA filter comes as close as possible to
648 % satisfying the above condition.
649 %
650 % Robidoux is another filter tuned for EWA. It is the Keys cubic filter
651 % defined by B=(228 - 108 sqrt(2))/199. Robidoux satisfies the "'No-Op'
652 % Vertical and Horizontal Line Preservation Condition" exactly, and it
653 % moderately blurs high frequency 'pixel-hash' patterns under no-op. It turns
654 % out to be close to both Mitchell and Lanczos2Sharp. For example, its first
655 % crossing is at (36 sqrt(2) + 123)/(72 sqrt(2) + 47), almost the same as the
656 % first crossing of Mitchell and Lanczos2Sharp.
657 %
658 % RodidouxSharp is a slightly sharper version of Rodidoux, some believe it
659 % is too sharp. It is designed to minimize the maximum possible change in
660 % a pixel value which is at one of the extremes (e.g., 0 or 255) under no-op
661 % conditions. Amazingly Mitchell falls roughly between Rodidoux and
662 % RodidouxSharp, though this seems to have been pure coincidence.
663 %
664 % 'EXPERT' OPTIONS:
665 %
666 % These artifact "defines" are not recommended for production use without
667 % expert knowledge of resampling, filtering, and the effects they have on the
668 % resulting resampled (resized or distorted) image.
669 %
670 % They can be used to override any and all filter default, and it is
671 % recommended you make good use of "filter:verbose" to make sure that the
672 % overall effect of your selection (before and after) is as expected.
673 %
674 % "filter:verbose" controls whether to output the exact results of the
675 % filter selections made, as well as plotting data for graphing the
676 % resulting filter over the filters support range.
677 %
678 % "filter:filter" select the main function associated with this filter
679 % name, as the weighting function of the filter. This can be used to
680 % set a windowing function as a weighting function, for special
681 % purposes, such as graphing.
682 %
683 % If a "filter:window" operation has not been provided, a 'Box'
684 % windowing function will be set to denote that no windowing function is
685 % being used.
686 %
687 % "filter:window" Select this windowing function for the filter. While any
688 % filter could be used as a windowing function, using the 'first lobe' of
689 % that filter over the whole support window, using a non-windowing
690 % function is not advisible. If no weighting filter function is specified
691 % a 'SincFast' filter is used.
692 %
693 % "filter:lobes" Number of lobes to use for the Sinc/Jinc filter. This a
694 % simpler method of setting filter support size that will correctly
695 % handle the Sinc/Jinc switch for an operators filtering requirements.
696 % Only integers should be given.
697 %
698 % "filter:support" Set the support size for filtering to the size given.
699 % This not recommended for Sinc/Jinc windowed filters (lobes should be
700 % used instead). This will override any 'filter:lobes' option.
701 %
702 % "filter:win-support" Scale windowing function to this size instead. This
703 % causes the windowing (or self-windowing Lagrange filter) to act is if
704 % the support window it much much larger than what is actually supplied
705 % to the calling operator. The filter however is still clipped to the
706 % real support size given, by the support range supplied to the caller.
707 % If unset this will equal the normal filter support size.
708 %
709 % "filter:blur" Scale the filter and support window by this amount. A value
710 % of > 1 will generally result in a more blurred image with more ringing
711 % effects, while a value <1 will sharpen the resulting image with more
712 % aliasing effects.
713 %
714 % "filter:sigma" The sigma value to use for the Gaussian filter only.
715 % Defaults to '1/2'. Using a different sigma effectively provides a
716 % method of using the filter as a 'blur' convolution. Particularly when
717 % using it for Distort.
718 %
719 % "filter:b"
720 % "filter:c" Override the preset B,C values for a Cubic filter.
721 % If only one of these are given it is assumes to be a 'Keys' type of
722 % filter such that B+2C=1, where Keys 'alpha' value = C.
723 %
724 % Examples:
725 %
726 % Set a true un-windowed Sinc filter with 10 lobes (very slow):
727 % -define filter:filter=Sinc
728 % -define filter:lobes=8
729 %
730 % Set an 8 lobe Lanczos (Sinc or Jinc) filter:
731 % -filter Lanczos
732 % -define filter:lobes=8
733 %
734 % The format of the AcquireResizeFilter method is:
735 %
736 % ResizeFilter *AcquireResizeFilter(const Image *image,
737 % const FilterType filter_type,const MagickBooleanType cylindrical,
738 % ExceptionInfo *exception)
739 %
740 % A description of each parameter follows:
741 %
742 % o image: the image.
743 %
744 % o filter: the filter type, defining a preset filter, window and support.
745 % The artifact settings listed above will override those selections.
746 %
747 % o blur: blur the filter by this amount, use 1.0 if unknown. Image
748 % artifact "filter:blur" will override this API call usage, including any
749 % internal change (such as for cylindrical usage).
750 %
751 % o radial: use a 1D orthogonal filter (Sinc) or 2D cylindrical (radial)
752 % filter (Jinc).
753 %
754 % o exception: return any errors or warnings in this structure.
755 %
756 */
758  const FilterType filter,const MagickBooleanType cylindrical,
759  ExceptionInfo *exception)
760 {
761  const char
762  *artifact;
763 
764  FilterType
765  filter_type,
766  window_type;
767 
768  double
769  B,
770  C,
771  value;
772 
773  register ResizeFilter
774  *resize_filter;
775 
776  /*
777  Table Mapping given Filter, into Weighting and Windowing functions.
778  A 'Box' windowing function means its a simble non-windowed filter.
779  An 'SincFast' filter function could be upgraded to a 'Jinc' filter if a
780  "cylindrical" is requested, unless a 'Sinc' or 'SincFast' filter was
781  specifically requested by the user.
782 
783  WARNING: The order of this table must match the order of the FilterType
784  enumeration specified in "resample.h", or the filter names will not match
785  the filter being setup.
786 
787  You can check filter setups with the "filter:verbose" expert setting.
788  */
789  static struct
790  {
791  FilterType
792  filter,
793  window;
794  } const mapping[SentinelFilter] =
795  {
796  { UndefinedFilter, BoxFilter }, /* Undefined (default to Box) */
797  { PointFilter, BoxFilter }, /* SPECIAL: Nearest neighbour */
798  { BoxFilter, BoxFilter }, /* Box averaging filter */
799  { TriangleFilter, BoxFilter }, /* Linear interpolation filter */
800  { HermiteFilter, BoxFilter }, /* Hermite interpolation filter */
801  { SincFastFilter, HannFilter }, /* Hann -- cosine-sinc */
802  { SincFastFilter, HammingFilter }, /* Hamming -- '' variation */
803  { SincFastFilter, BlackmanFilter }, /* Blackman -- 2*cosine-sinc */
804  { GaussianFilter, BoxFilter }, /* Gaussian blur filter */
805  { QuadraticFilter, BoxFilter }, /* Quadratic Gaussian approx */
806  { CubicFilter, BoxFilter }, /* General Cubic Filter, Spline */
807  { CatromFilter, BoxFilter }, /* Cubic-Keys interpolator */
808  { MitchellFilter, BoxFilter }, /* 'Ideal' Cubic-Keys filter */
809  { JincFilter, BoxFilter }, /* Raw 3-lobed Jinc function */
810  { SincFilter, BoxFilter }, /* Raw 4-lobed Sinc function */
811  { SincFastFilter, BoxFilter }, /* Raw fast sinc ("Pade"-type) */
812  { SincFastFilter, KaiserFilter }, /* Kaiser -- square root-sinc */
813  { LanczosFilter, WelchFilter }, /* Welch -- parabolic (3 lobe) */
814  { SincFastFilter, CubicFilter }, /* Parzen -- cubic-sinc */
815  { SincFastFilter, BohmanFilter }, /* Bohman -- 2*cosine-sinc */
816  { SincFastFilter, TriangleFilter }, /* Bartlett -- triangle-sinc */
817  { LagrangeFilter, BoxFilter }, /* Lagrange self-windowing */
818  { LanczosFilter, LanczosFilter }, /* Lanczos Sinc-Sinc filters */
819  { LanczosSharpFilter, LanczosSharpFilter }, /* | these require */
820  { Lanczos2Filter, Lanczos2Filter }, /* | special handling */
822  { RobidouxFilter, BoxFilter }, /* Cubic Keys tuned for EWA */
823  { RobidouxSharpFilter, BoxFilter }, /* Sharper Cubic Keys for EWA */
824  { LanczosFilter, CosineFilter }, /* Cosine window (3 lobes) */
825  { SplineFilter, BoxFilter }, /* Spline Cubic Filter */
826  { LanczosRadiusFilter, LanczosFilter }, /* Lanczos with integer radius */
827  { CubicSplineFilter, BoxFilter }, /* CubicSpline (2/3/4 lobes) */
828  };
829  /*
830  Table mapping the filter/window from the above table to an actual function.
831  The default support size for that filter as a weighting function, the range
832  to scale with to use that function as a sinc windowing function, (typ 1.0).
833 
834  Note that the filter_type -> function is 1 to 1 except for Sinc(),
835  SincFast(), and CubicBC() functions, which may have multiple filter to
836  function associations.
837 
838  See "filter:verbose" handling below for the function -> filter mapping.
839  */
840  static struct
841  {
842  double
843  (*function)(const double,const ResizeFilter*),
844  support, /* Default lobes/support size of the weighting filter. */
845  scale, /* Support when function used as a windowing function
846  Typically equal to the location of the first zero crossing. */
847  B,C; /* BC-spline coefficients, ignored if not a CubicBC filter. */
848  ResizeWeightingFunctionType weightingFunctionType;
849  } const filters[SentinelFilter] =
850  {
851  /* .--- support window (if used as a Weighting Function)
852  | .--- first crossing (if used as a Windowing Function)
853  | | .--- B value for Cubic Function
854  | | | .---- C value for Cubic Function
855  | | | | */
856  { Box, 0.5, 0.5, 0.0, 0.0, BoxWeightingFunction }, /* Undefined (default to Box) */
857  { Box, 0.0, 0.5, 0.0, 0.0, BoxWeightingFunction }, /* Point (special handling) */
858  { Box, 0.5, 0.5, 0.0, 0.0, BoxWeightingFunction }, /* Box */
859  { Triangle, 1.0, 1.0, 0.0, 0.0, TriangleWeightingFunction }, /* Triangle */
860  { CubicBC, 1.0, 1.0, 0.0, 0.0, CubicBCWeightingFunction }, /* Hermite (cubic B=C=0) */
861  { Hann, 1.0, 1.0, 0.0, 0.0, HannWeightingFunction }, /* Hann, cosine window */
862  { Hamming, 1.0, 1.0, 0.0, 0.0, HammingWeightingFunction }, /* Hamming, '' variation */
863  { Blackman, 1.0, 1.0, 0.0, 0.0, BlackmanWeightingFunction }, /* Blackman, 2*cosine window */
864  { Gaussian, 2.0, 1.5, 0.0, 0.0, GaussianWeightingFunction }, /* Gaussian */
865  { Quadratic, 1.5, 1.5, 0.0, 0.0, QuadraticWeightingFunction },/* Quadratic gaussian */
866  { CubicBC, 2.0, 2.0, 1.0, 0.0, CubicBCWeightingFunction }, /* General Cubic Filter */
867  { CubicBC, 2.0, 1.0, 0.0, 0.5, CubicBCWeightingFunction }, /* Catmull-Rom (B=0,C=1/2) */
868  { CubicBC, 2.0, 8.0/7.0, 1./3., 1./3., CubicBCWeightingFunction }, /* Mitchell (B=C=1/3) */
869  { Jinc, 3.0, 1.2196698912665045, 0.0, 0.0, JincWeightingFunction }, /* Raw 3-lobed Jinc */
870  { Sinc, 4.0, 1.0, 0.0, 0.0, SincWeightingFunction }, /* Raw 4-lobed Sinc */
871  { SincFast, 4.0, 1.0, 0.0, 0.0, SincFastWeightingFunction }, /* Raw fast sinc ("Pade"-type) */
872  { Kaiser, 1.0, 1.0, 0.0, 0.0, KaiserWeightingFunction }, /* Kaiser (square root window) */
873  { Welch, 1.0, 1.0, 0.0, 0.0, WelchWeightingFunction }, /* Welch (parabolic window) */
874  { CubicBC, 2.0, 2.0, 1.0, 0.0, CubicBCWeightingFunction }, /* Parzen (B-Spline window) */
875  { Bohman, 1.0, 1.0, 0.0, 0.0, BohmanWeightingFunction }, /* Bohman, 2*Cosine window */
876  { Triangle, 1.0, 1.0, 0.0, 0.0, TriangleWeightingFunction }, /* Bartlett (triangle window) */
877  { Lagrange, 2.0, 1.0, 0.0, 0.0, LagrangeWeightingFunction }, /* Lagrange sinc approximation */
878  { SincFast, 3.0, 1.0, 0.0, 0.0, SincFastWeightingFunction }, /* Lanczos, 3-lobed Sinc-Sinc */
879  { SincFast, 3.0, 1.0, 0.0, 0.0, SincFastWeightingFunction }, /* Lanczos, Sharpened */
880  { SincFast, 2.0, 1.0, 0.0, 0.0, SincFastWeightingFunction }, /* Lanczos, 2-lobed */
881  { SincFast, 2.0, 1.0, 0.0, 0.0, SincFastWeightingFunction }, /* Lanczos2, sharpened */
882  /* Robidoux: Keys cubic close to Lanczos2D sharpened */
883  { CubicBC, 2.0, 1.1685777620836932,
884  0.37821575509399867, 0.31089212245300067, CubicBCWeightingFunction },
885  /* RobidouxSharp: Sharper version of Robidoux */
886  { CubicBC, 2.0, 1.105822933719019,
887  0.2620145123990142, 0.3689927438004929, CubicBCWeightingFunction },
888  { Cosine, 1.0, 1.0, 0.0, 0.0, CosineWeightingFunction }, /* Low level cosine window */
889  { CubicBC, 2.0, 2.0, 1.0, 0.0, CubicBCWeightingFunction }, /* Cubic B-Spline (B=1,C=0) */
890  { SincFast, 3.0, 1.0, 0.0, 0.0, SincFastWeightingFunction }, /* Lanczos, Interger Radius */
891  { CubicSpline,2.0, 0.5, 0.0, 0.0, BoxWeightingFunction }, /* Spline Lobes 2-lobed */
892  };
893  /*
894  The known zero crossings of the Jinc() or more accurately the Jinc(x*PI)
895  function being used as a filter. It is used by the "filter:lobes" expert
896  setting and for 'lobes' for Jinc functions in the previous table. This way
897  users do not have to deal with the highly irrational lobe sizes of the Jinc
898  filter.
899 
900  Values taken from
901  http://cose.math.bas.bg/webMathematica/webComputing/BesselZeros.jsp
902  using Jv-function with v=1, then dividing by PI.
903  */
904  static double
905  jinc_zeros[16] =
906  {
907  1.2196698912665045,
908  2.2331305943815286,
909  3.2383154841662362,
910  4.2410628637960699,
911  5.2427643768701817,
912  6.2439216898644877,
913  7.2447598687199570,
914  8.2453949139520427,
915  9.2458926849494673,
916  10.246293348754916,
917  11.246622794877883,
918  12.246898461138105,
919  13.247132522181061,
920  14.247333735806849,
921  15.247508563037300,
922  16.247661874700962
923  };
924 
925  /*
926  Allocate resize filter.
927  */
928  assert(image != (const Image *) NULL);
929  assert(image->signature == MagickCoreSignature);
930  if (image->debug != MagickFalse)
931  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
932  assert(UndefinedFilter < filter && filter < SentinelFilter);
933  assert(exception != (ExceptionInfo *) NULL);
934  assert(exception->signature == MagickCoreSignature);
935  (void) exception;
936  resize_filter=(ResizeFilter *) AcquireCriticalMemory(sizeof(*resize_filter));
937  (void) memset(resize_filter,0,sizeof(*resize_filter));
938  /*
939  Defaults for the requested filter.
940  */
941  filter_type=mapping[filter].filter;
942  window_type=mapping[filter].window;
943  resize_filter->blur=1.0;
944  /* Promote 1D Windowed Sinc Filters to a 2D Windowed Jinc filters */
945  if ((cylindrical != MagickFalse) && (filter_type == SincFastFilter) &&
946  (filter != SincFastFilter))
947  filter_type=JincFilter; /* 1D Windowed Sinc => 2D Windowed Jinc filters */
948 
949  /* Expert filter setting override */
950  artifact=GetImageArtifact(image,"filter:filter");
951  if (IsStringTrue(artifact) != MagickFalse)
952  {
953  ssize_t
954  option;
955 
957  if ((UndefinedFilter < option) && (option < SentinelFilter))
958  { /* Raw filter request - no window function. */
959  filter_type=(FilterType) option;
960  window_type=BoxFilter;
961  }
962  /* Filter override with a specific window function. */
963  artifact=GetImageArtifact(image,"filter:window");
964  if (artifact != (const char *) NULL)
965  {
967  if ((UndefinedFilter < option) && (option < SentinelFilter))
968  window_type=(FilterType) option;
969  }
970  }
971  else
972  {
973  /* Window specified, but no filter function? Assume Sinc/Jinc. */
974  artifact=GetImageArtifact(image,"filter:window");
975  if (artifact != (const char *) NULL)
976  {
977  ssize_t
978  option;
979 
981  if ((UndefinedFilter < option) && (option < SentinelFilter))
982  {
983  filter_type= cylindrical != MagickFalse ? JincFilter
984  : SincFastFilter;
985  window_type=(FilterType) option;
986  }
987  }
988  }
989 
990  /* Assign the real functions to use for the filters selected. */
991  resize_filter->filter=filters[filter_type].function;
992  resize_filter->support=filters[filter_type].support;
993  resize_filter->filterWeightingType=filters[filter_type].weightingFunctionType;
994  resize_filter->window=filters[window_type].function;
995  resize_filter->windowWeightingType=filters[window_type].weightingFunctionType;
996  resize_filter->scale=filters[window_type].scale;
997  resize_filter->signature=MagickCoreSignature;
998 
999  /* Filter Modifications for orthogonal/cylindrical usage */
1000  if (cylindrical != MagickFalse)
1001  switch (filter_type)
1002  {
1003  case BoxFilter:
1004  /* Support for Cylindrical Box should be sqrt(2)/2 */
1005  resize_filter->support=(double) MagickSQ1_2;
1006  break;
1007  case LanczosFilter:
1008  case LanczosSharpFilter:
1009  case Lanczos2Filter:
1010  case Lanczos2SharpFilter:
1011  case LanczosRadiusFilter:
1012  resize_filter->filter=filters[JincFilter].function;
1013  resize_filter->window=filters[JincFilter].function;
1014  resize_filter->scale=filters[JincFilter].scale;
1015  /* number of lobes (support window size) remain unchanged */
1016  break;
1017  default:
1018  break;
1019  }
1020  /* Global Sharpening (regardless of orthoginal/cylindrical) */
1021  switch (filter_type)
1022  {
1023  case LanczosSharpFilter:
1024  resize_filter->blur *= 0.9812505644269356;
1025  break;
1026  case Lanczos2SharpFilter:
1027  resize_filter->blur *= 0.9549963639785485;
1028  break;
1029  /* case LanczosRadius: blur adjust is done after lobes */
1030  default:
1031  break;
1032  }
1033 
1034  /*
1035  Expert Option Modifications.
1036  */
1037 
1038  /* User Gaussian Sigma Override - no support change */
1039  if ((resize_filter->filter == Gaussian) ||
1040  (resize_filter->window == Gaussian) ) {
1041  value=0.5; /* guassian sigma default, half pixel */
1042  artifact=GetImageArtifact(image,"filter:sigma");
1043  if (artifact != (const char *) NULL)
1044  value=StringToDouble(artifact,(char **) NULL);
1045  /* Define coefficents for Gaussian */
1046  resize_filter->coefficient[0]=value; /* note sigma too */
1047  resize_filter->coefficient[1]=PerceptibleReciprocal(2.0*value*value); /* sigma scaling */
1048  resize_filter->coefficient[2]=PerceptibleReciprocal(Magick2PI*value*value);
1049  /* normalization - not actually needed or used! */
1050  if ( value > 0.5 )
1051  resize_filter->support *= 2*value; /* increase support linearly */
1052  }
1053 
1054  /* User Kaiser Alpha Override - no support change */
1055  if ((resize_filter->filter == Kaiser) ||
1056  (resize_filter->window == Kaiser) ) {
1057  value=6.5; /* default beta value for Kaiser bessel windowing function */
1058  artifact=GetImageArtifact(image,"filter:alpha"); /* FUTURE: depreciate */
1059  if (artifact != (const char *) NULL)
1060  value=StringToDouble(artifact,(char **) NULL);
1061  artifact=GetImageArtifact(image,"filter:kaiser-beta");
1062  if (artifact != (const char *) NULL)
1063  value=StringToDouble(artifact,(char **) NULL);
1064  artifact=GetImageArtifact(image,"filter:kaiser-alpha");
1065  if (artifact != (const char *) NULL)
1066  value=StringToDouble(artifact,(char **) NULL)*MagickPI;
1067  /* Define coefficents for Kaiser Windowing Function */
1068  resize_filter->coefficient[0]=value; /* alpha */
1069  resize_filter->coefficient[1]=PerceptibleReciprocal(I0(value));
1070  /* normalization */
1071  }
1072 
1073  /* Support Overrides */
1074  artifact=GetImageArtifact(image,"filter:lobes");
1075  if (artifact != (const char *) NULL)
1076  {
1077  ssize_t
1078  lobes;
1079 
1080  lobes=(ssize_t) StringToLong(artifact);
1081  if (lobes < 1)
1082  lobes=1;
1083  resize_filter->support=(double) lobes;
1084  }
1085  if (resize_filter->filter == Jinc)
1086  {
1087  /*
1088  Convert a Jinc function lobes value to a real support value.
1089  */
1090  if (resize_filter->support > 16)
1091  resize_filter->support=jinc_zeros[15]; /* largest entry in table */
1092  else
1093  resize_filter->support=jinc_zeros[((long) resize_filter->support)-1];
1094  /*
1095  Blur this filter so support is a integer value (lobes dependant).
1096  */
1097  if (filter_type == LanczosRadiusFilter)
1098  resize_filter->blur*=floor(resize_filter->support)/
1099  resize_filter->support;
1100  }
1101  /*
1102  Expert blur override.
1103  */
1104  artifact=GetImageArtifact(image,"filter:blur");
1105  if (artifact != (const char *) NULL)
1106  resize_filter->blur*=StringToDouble(artifact,(char **) NULL);
1107  if (resize_filter->blur < MagickEpsilon)
1108  resize_filter->blur=(double) MagickEpsilon;
1109  /*
1110  Expert override of the support setting.
1111  */
1112  artifact=GetImageArtifact(image,"filter:support");
1113  if (artifact != (const char *) NULL)
1114  resize_filter->support=fabs(StringToDouble(artifact,(char **) NULL));
1115  /*
1116  Scale windowing function separately to the support 'clipping' window
1117  that calling operator is planning to actually use. (Expert override)
1118  */
1119  resize_filter->window_support=resize_filter->support; /* default */
1120  artifact=GetImageArtifact(image,"filter:win-support");
1121  if (artifact != (const char *) NULL)
1122  resize_filter->window_support=fabs(StringToDouble(artifact,(char **) NULL));
1123  /*
1124  Adjust window function scaling to match windowing support for weighting
1125  function. This avoids a division on every filter call.
1126  */
1127  resize_filter->scale*=PerceptibleReciprocal(resize_filter->window_support);
1128  /*
1129  Set Cubic Spline B,C values, calculate Cubic coefficients.
1130  */
1131  B=0.0;
1132  C=0.0;
1133  if ((resize_filter->filter == CubicBC) ||
1134  (resize_filter->window == CubicBC) )
1135  {
1136  B=filters[filter_type].B;
1137  C=filters[filter_type].C;
1138  if (filters[window_type].function == CubicBC)
1139  {
1140  B=filters[window_type].B;
1141  C=filters[window_type].C;
1142  }
1143  artifact=GetImageArtifact(image,"filter:b");
1144  if (artifact != (const char *) NULL)
1145  {
1146  B=StringToDouble(artifact,(char **) NULL);
1147  C=(1.0-B)/2.0; /* Calculate C to get a Keys cubic filter. */
1148  artifact=GetImageArtifact(image,"filter:c"); /* user C override */
1149  if (artifact != (const char *) NULL)
1150  C=StringToDouble(artifact,(char **) NULL);
1151  }
1152  else
1153  {
1154  artifact=GetImageArtifact(image,"filter:c");
1155  if (artifact != (const char *) NULL)
1156  {
1157  C=StringToDouble(artifact,(char **) NULL);
1158  B=1.0-2.0*C; /* Calculate B to get a Keys cubic filter. */
1159  }
1160  }
1161  {
1162  const double
1163  twoB = B+B;
1164 
1165  /*
1166  Convert B,C values into Cubic Coefficents. See CubicBC().
1167  */
1168  resize_filter->coefficient[0]=1.0-(1.0/3.0)*B;
1169  resize_filter->coefficient[1]=-3.0+twoB+C;
1170  resize_filter->coefficient[2]=2.0-1.5*B-C;
1171  resize_filter->coefficient[3]=(4.0/3.0)*B+4.0*C;
1172  resize_filter->coefficient[4]=-8.0*C-twoB;
1173  resize_filter->coefficient[5]=B+5.0*C;
1174  resize_filter->coefficient[6]=(-1.0/6.0)*B-C;
1175  }
1176  }
1177 
1178  /*
1179  Expert Option Request for verbose details of the resulting filter.
1180  */
1181 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1182  #pragma omp master
1183  {
1184 #endif
1185  if (IsStringTrue(GetImageArtifact(image,"filter:verbose")) != MagickFalse)
1186  {
1187  double
1188  support,
1189  x;
1190 
1191  /*
1192  Set the weighting function properly when the weighting function
1193  may not exactly match the filter of the same name. EG: a Point
1194  filter is really uses a Box weighting function with a different
1195  support than is typically used.
1196  */
1197  if (resize_filter->filter == Box) filter_type=BoxFilter;
1198  if (resize_filter->filter == Sinc) filter_type=SincFilter;
1199  if (resize_filter->filter == SincFast) filter_type=SincFastFilter;
1200  if (resize_filter->filter == Jinc) filter_type=JincFilter;
1201  if (resize_filter->filter == CubicBC) filter_type=CubicFilter;
1202  if (resize_filter->window == Box) window_type=BoxFilter;
1203  if (resize_filter->window == Sinc) window_type=SincFilter;
1204  if (resize_filter->window == SincFast) window_type=SincFastFilter;
1205  if (resize_filter->window == Jinc) window_type=JincFilter;
1206  if (resize_filter->window == CubicBC) window_type=CubicFilter;
1207  /*
1208  Report Filter Details.
1209  */
1210  support=GetResizeFilterSupport(resize_filter); /* practical_support */
1211  (void) FormatLocaleFile(stdout,
1212  "# Resampling Filter (for graphing)\n#\n");
1213  (void) FormatLocaleFile(stdout,"# filter = %s\n",
1215  (void) FormatLocaleFile(stdout,"# window = %s\n",
1217  (void) FormatLocaleFile(stdout,"# support = %.*g\n",
1218  GetMagickPrecision(),(double) resize_filter->support);
1219  (void) FormatLocaleFile(stdout,"# window-support = %.*g\n",
1220  GetMagickPrecision(),(double) resize_filter->window_support);
1221  (void) FormatLocaleFile(stdout,"# scale-blur = %.*g\n",
1222  GetMagickPrecision(),(double) resize_filter->blur);
1223  if ((filter_type == GaussianFilter) || (window_type == GaussianFilter))
1224  (void) FormatLocaleFile(stdout,"# gaussian-sigma = %.*g\n",
1225  GetMagickPrecision(),(double) resize_filter->coefficient[0]);
1226  if ( filter_type == KaiserFilter || window_type == KaiserFilter )
1227  (void) FormatLocaleFile(stdout,"# kaiser-beta = %.*g\n",
1228  GetMagickPrecision(),(double) resize_filter->coefficient[0]);
1229  (void) FormatLocaleFile(stdout,"# practical-support = %.*g\n",
1230  GetMagickPrecision(), (double) support);
1231  if ((filter_type == CubicFilter) || (window_type == CubicFilter))
1232  (void) FormatLocaleFile(stdout,"# B,C = %.*g,%.*g\n",
1233  GetMagickPrecision(),(double) B,GetMagickPrecision(),(double) C);
1234  (void) FormatLocaleFile(stdout,"\n");
1235  /*
1236  Output values of resulting filter graph -- for graphing filter result.
1237  */
1238  for (x=0.0; x <= support; x+=0.01f)
1239  (void) FormatLocaleFile(stdout,"%5.2lf\t%.*g\n",x,
1240  GetMagickPrecision(),(double)
1241  GetResizeFilterWeight(resize_filter,x));
1242  /*
1243  A final value so gnuplot can graph the 'stop' properly.
1244  */
1245  (void) FormatLocaleFile(stdout,"%5.2lf\t%.*g\n",support,
1246  GetMagickPrecision(),0.0);
1247  }
1248  /* Output the above once only for each image - remove setting */
1249  (void) DeleteImageArtifact((Image *) image,"filter:verbose");
1250 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1251  }
1252 #endif
1253  return(resize_filter);
1254 }
1255 
1256 /*
1257 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1258 % %
1259 % %
1260 % %
1261 % A d a p t i v e R e s i z e I m a g e %
1262 % %
1263 % %
1264 % %
1265 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1266 %
1267 % AdaptiveResizeImage() adaptively resize image with pixel resampling.
1268 %
1269 % This is shortcut function for a fast interpolative resize using mesh
1270 % interpolation. It works well for small resizes of less than +/- 50%
1271 % of the original image size. For larger resizing on images a full
1272 % filtered and slower resize function should be used instead.
1273 %
1274 % The format of the AdaptiveResizeImage method is:
1275 %
1276 % Image *AdaptiveResizeImage(const Image *image,const size_t columns,
1277 % const size_t rows,ExceptionInfo *exception)
1278 %
1279 % A description of each parameter follows:
1280 %
1281 % o image: the image.
1282 %
1283 % o columns: the number of columns in the resized image.
1284 %
1285 % o rows: the number of rows in the resized image.
1286 %
1287 % o exception: return any errors or warnings in this structure.
1288 %
1289 */
1291  const size_t columns,const size_t rows,ExceptionInfo *exception)
1292 {
1293  Image
1294  *resize_image;
1295 
1296  resize_image=InterpolativeResizeImage(image,columns,rows,MeshInterpolatePixel,
1297  exception);
1298  return(resize_image);
1299 }
1300 
1301 /*
1302 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1303 % %
1304 % %
1305 % %
1306 + B e s s e l O r d e r O n e %
1307 % %
1308 % %
1309 % %
1310 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1311 %
1312 % BesselOrderOne() computes the Bessel function of x of the first kind of
1313 % order 0. This is used to create the Jinc() filter function below.
1314 %
1315 % Reduce x to |x| since j1(x)= -j1(-x), and for x in (0,8]
1316 %
1317 % j1(x) = x*j1(x);
1318 %
1319 % For x in (8,inf)
1320 %
1321 % j1(x) = sqrt(2/(pi*x))*(p1(x)*cos(x1)-q1(x)*sin(x1))
1322 %
1323 % where x1 = x-3*pi/4. Compute sin(x1) and cos(x1) as follow:
1324 %
1325 % cos(x1) = cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
1326 % = 1/sqrt(2) * (sin(x) - cos(x))
1327 % sin(x1) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
1328 % = -1/sqrt(2) * (sin(x) + cos(x))
1329 %
1330 % The format of the BesselOrderOne method is:
1331 %
1332 % double BesselOrderOne(double x)
1333 %
1334 % A description of each parameter follows:
1335 %
1336 % o x: double value.
1337 %
1338 */
1339 
1340 #undef I0
1341 static double I0(double x)
1342 {
1343  double
1344  sum,
1345  t,
1346  y;
1347 
1348  register ssize_t
1349  i;
1350 
1351  /*
1352  Zeroth order Bessel function of the first kind.
1353  */
1354  sum=1.0;
1355  y=x*x/4.0;
1356  t=y;
1357  for (i=2; t > MagickEpsilon; i++)
1358  {
1359  sum+=t;
1360  t*=y/((double) i*i);
1361  }
1362  return(sum);
1363 }
1364 
1365 #undef J1
1366 static double J1(double x)
1367 {
1368  double
1369  p,
1370  q;
1371 
1372  register ssize_t
1373  i;
1374 
1375  static const double
1376  Pone[] =
1377  {
1378  0.581199354001606143928050809e+21,
1379  -0.6672106568924916298020941484e+20,
1380  0.2316433580634002297931815435e+19,
1381  -0.3588817569910106050743641413e+17,
1382  0.2908795263834775409737601689e+15,
1383  -0.1322983480332126453125473247e+13,
1384  0.3413234182301700539091292655e+10,
1385  -0.4695753530642995859767162166e+7,
1386  0.270112271089232341485679099e+4
1387  },
1388  Qone[] =
1389  {
1390  0.11623987080032122878585294e+22,
1391  0.1185770712190320999837113348e+20,
1392  0.6092061398917521746105196863e+17,
1393  0.2081661221307607351240184229e+15,
1394  0.5243710262167649715406728642e+12,
1395  0.1013863514358673989967045588e+10,
1396  0.1501793594998585505921097578e+7,
1397  0.1606931573481487801970916749e+4,
1398  0.1e+1
1399  };
1400 
1401  p=Pone[8];
1402  q=Qone[8];
1403  for (i=7; i >= 0; i--)
1404  {
1405  p=p*x*x+Pone[i];
1406  q=q*x*x+Qone[i];
1407  }
1408  return(p/q);
1409 }
1410 
1411 #undef P1
1412 static double P1(double x)
1413 {
1414  double
1415  p,
1416  q;
1417 
1418  register ssize_t
1419  i;
1420 
1421  static const double
1422  Pone[] =
1423  {
1424  0.352246649133679798341724373e+5,
1425  0.62758845247161281269005675e+5,
1426  0.313539631109159574238669888e+5,
1427  0.49854832060594338434500455e+4,
1428  0.2111529182853962382105718e+3,
1429  0.12571716929145341558495e+1
1430  },
1431  Qone[] =
1432  {
1433  0.352246649133679798068390431e+5,
1434  0.626943469593560511888833731e+5,
1435  0.312404063819041039923015703e+5,
1436  0.4930396490181088979386097e+4,
1437  0.2030775189134759322293574e+3,
1438  0.1e+1
1439  };
1440 
1441  p=Pone[5];
1442  q=Qone[5];
1443  for (i=4; i >= 0; i--)
1444  {
1445  p=p*(8.0/x)*(8.0/x)+Pone[i];
1446  q=q*(8.0/x)*(8.0/x)+Qone[i];
1447  }
1448  return(p/q);
1449 }
1450 
1451 #undef Q1
1452 static double Q1(double x)
1453 {
1454  double
1455  p,
1456  q;
1457 
1458  register ssize_t
1459  i;
1460 
1461  static const double
1462  Pone[] =
1463  {
1464  0.3511751914303552822533318e+3,
1465  0.7210391804904475039280863e+3,
1466  0.4259873011654442389886993e+3,
1467  0.831898957673850827325226e+2,
1468  0.45681716295512267064405e+1,
1469  0.3532840052740123642735e-1
1470  },
1471  Qone[] =
1472  {
1473  0.74917374171809127714519505e+4,
1474  0.154141773392650970499848051e+5,
1475  0.91522317015169922705904727e+4,
1476  0.18111867005523513506724158e+4,
1477  0.1038187585462133728776636e+3,
1478  0.1e+1
1479  };
1480 
1481  p=Pone[5];
1482  q=Qone[5];
1483  for (i=4; i >= 0; i--)
1484  {
1485  p=p*(8.0/x)*(8.0/x)+Pone[i];
1486  q=q*(8.0/x)*(8.0/x)+Qone[i];
1487  }
1488  return(p/q);
1489 }
1490 
1491 static double BesselOrderOne(double x)
1492 {
1493  double
1494  p,
1495  q;
1496 
1497  if (x == 0.0)
1498  return(0.0);
1499  p=x;
1500  if (x < 0.0)
1501  x=(-x);
1502  if (x < 8.0)
1503  return(p*J1(x));
1504  q=sqrt((double) (2.0/(MagickPI*x)))*(P1(x)*(1.0/sqrt(2.0)*(sin(x)-
1505  cos(x)))-8.0/x*Q1(x)*(-1.0/sqrt(2.0)*(sin(x)+cos(x))));
1506  if (p < 0.0)
1507  q=(-q);
1508  return(q);
1509 }
1510 
1511 /*
1512 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1513 % %
1514 % %
1515 % %
1516 + D e s t r o y R e s i z e F i l t e r %
1517 % %
1518 % %
1519 % %
1520 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1521 %
1522 % DestroyResizeFilter() destroy the resize filter.
1523 %
1524 % The format of the DestroyResizeFilter method is:
1525 %
1526 % ResizeFilter *DestroyResizeFilter(ResizeFilter *resize_filter)
1527 %
1528 % A description of each parameter follows:
1529 %
1530 % o resize_filter: the resize filter.
1531 %
1532 */
1534 {
1535  assert(resize_filter != (ResizeFilter *) NULL);
1536  assert(resize_filter->signature == MagickCoreSignature);
1537  resize_filter->signature=(~MagickCoreSignature);
1538  resize_filter=(ResizeFilter *) RelinquishMagickMemory(resize_filter);
1539  return(resize_filter);
1540 }
1541 
1542 /*
1543 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1544 % %
1545 % %
1546 % %
1547 + G e t R e s i z e F i l t e r S u p p o r t %
1548 % %
1549 % %
1550 % %
1551 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1552 %
1553 % GetResizeFilterSupport() return the current support window size for this
1554 % filter. Note that this may have been enlarged by filter:blur factor.
1555 %
1556 % The format of the GetResizeFilterSupport method is:
1557 %
1558 % double GetResizeFilterSupport(const ResizeFilter *resize_filter)
1559 %
1560 % A description of each parameter follows:
1561 %
1562 % o filter: Image filter to use.
1563 %
1564 */
1565 
1567  const ResizeFilter *resize_filter)
1568 {
1569  assert(resize_filter != (ResizeFilter *) NULL);
1570  assert(resize_filter->signature == MagickCoreSignature);
1571  return((double *) resize_filter->coefficient);
1572 }
1573 
1574 MagickPrivate double GetResizeFilterBlur(const ResizeFilter *resize_filter)
1575 {
1576  assert(resize_filter != (ResizeFilter *) NULL);
1577  assert(resize_filter->signature == MagickCoreSignature);
1578  return(resize_filter->blur);
1579 }
1580 
1582 {
1583  assert(resize_filter != (ResizeFilter *) NULL);
1584  assert(resize_filter->signature == MagickCoreSignature);
1585  return(resize_filter->scale);
1586 }
1587 
1589  const ResizeFilter *resize_filter)
1590 {
1591  assert(resize_filter != (ResizeFilter *) NULL);
1592  assert(resize_filter->signature == MagickCoreSignature);
1593  return(resize_filter->window_support);
1594 }
1595 
1597  const ResizeFilter *resize_filter)
1598 {
1599  assert(resize_filter != (ResizeFilter *) NULL);
1600  assert(resize_filter->signature == MagickCoreSignature);
1601  return(resize_filter->filterWeightingType);
1602 }
1603 
1605  const ResizeFilter *resize_filter)
1606 {
1607  assert(resize_filter != (ResizeFilter *) NULL);
1608  assert(resize_filter->signature == MagickCoreSignature);
1609  return(resize_filter->windowWeightingType);
1610 }
1611 
1613 {
1614  assert(resize_filter != (ResizeFilter *) NULL);
1615  assert(resize_filter->signature == MagickCoreSignature);
1616  return(resize_filter->support*resize_filter->blur);
1617 }
1618 
1619 /*
1620 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1621 % %
1622 % %
1623 % %
1624 + G e t R e s i z e F i l t e r W e i g h t %
1625 % %
1626 % %
1627 % %
1628 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1629 %
1630 % GetResizeFilterWeight evaluates the specified resize filter at the point x
1631 % which usally lies between zero and the filters current 'support' and
1632 % returns the weight of the filter function at that point.
1633 %
1634 % The format of the GetResizeFilterWeight method is:
1635 %
1636 % double GetResizeFilterWeight(const ResizeFilter *resize_filter,
1637 % const double x)
1638 %
1639 % A description of each parameter follows:
1640 %
1641 % o filter: the filter type.
1642 %
1643 % o x: the point.
1644 %
1645 */
1647  const double x)
1648 {
1649  double
1650  scale,
1651  weight,
1652  x_blur;
1653 
1654  /*
1655  Windowing function - scale the weighting filter by this amount.
1656  */
1657  assert(resize_filter != (ResizeFilter *) NULL);
1658  assert(resize_filter->signature == MagickCoreSignature);
1659  x_blur=fabs((double) x)/resize_filter->blur; /* X offset with blur scaling */
1660  if ((resize_filter->window_support < MagickEpsilon) ||
1661  (resize_filter->window == Box))
1662  scale=1.0; /* Point or Box Filter -- avoid division by zero */
1663  else
1664  {
1665  scale=resize_filter->scale;
1666  scale=resize_filter->window(x_blur*scale,resize_filter);
1667  }
1668  weight=scale*resize_filter->filter(x_blur,resize_filter);
1669  return(weight);
1670 }
1671 
1672 /*
1673 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1674 % %
1675 % %
1676 % %
1677 % I n t e r p o l a t i v e R e s i z e I m a g e %
1678 % %
1679 % %
1680 % %
1681 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1682 %
1683 % InterpolativeResizeImage() resizes an image using the specified
1684 % interpolation method.
1685 %
1686 % The format of the InterpolativeResizeImage method is:
1687 %
1688 % Image *InterpolativeResizeImage(const Image *image,const size_t columns,
1689 % const size_t rows,const PixelInterpolateMethod method,
1690 % ExceptionInfo *exception)
1691 %
1692 % A description of each parameter follows:
1693 %
1694 % o image: the image.
1695 %
1696 % o columns: the number of columns in the resized image.
1697 %
1698 % o rows: the number of rows in the resized image.
1699 %
1700 % o method: the pixel interpolation method.
1701 %
1702 % o exception: return any errors or warnings in this structure.
1703 %
1704 */
1706  const size_t columns,const size_t rows,const PixelInterpolateMethod method,
1707  ExceptionInfo *exception)
1708 {
1709 #define InterpolativeResizeImageTag "Resize/Image"
1710 
1711  CacheView
1712  *image_view,
1713  *resize_view;
1714 
1715  Image
1716  *resize_image;
1717 
1719  status;
1720 
1722  progress;
1723 
1724  PointInfo
1725  scale;
1726 
1727  ssize_t
1728  y;
1729 
1730  /*
1731  Interpolatively resize image.
1732  */
1733  assert(image != (const Image *) NULL);
1734  assert(image->signature == MagickCoreSignature);
1735  if (image->debug != MagickFalse)
1736  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1737  assert(exception != (ExceptionInfo *) NULL);
1738  assert(exception->signature == MagickCoreSignature);
1739  if ((columns == 0) || (rows == 0))
1740  ThrowImageException(ImageError,"NegativeOrZeroImageSize");
1741  if ((columns == image->columns) && (rows == image->rows))
1742  return(CloneImage(image,0,0,MagickTrue,exception));
1743  resize_image=CloneImage(image,columns,rows,MagickTrue,exception);
1744  if (resize_image == (Image *) NULL)
1745  return((Image *) NULL);
1746  if (SetImageStorageClass(resize_image,DirectClass,exception) == MagickFalse)
1747  {
1748  resize_image=DestroyImage(resize_image);
1749  return((Image *) NULL);
1750  }
1751  status=MagickTrue;
1752  progress=0;
1753  image_view=AcquireVirtualCacheView(image,exception);
1754  resize_view=AcquireAuthenticCacheView(resize_image,exception);
1755  scale.x=(double) image->columns/resize_image->columns;
1756  scale.y=(double) image->rows/resize_image->rows;
1757 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1758  #pragma omp parallel for schedule(static) shared(progress,status) \
1759  magick_number_threads(image,resize_image,resize_image->rows,1)
1760 #endif
1761  for (y=0; y < (ssize_t) resize_image->rows; y++)
1762  {
1763  PointInfo
1764  offset;
1765 
1766  register Quantum
1767  *magick_restrict q;
1768 
1769  register ssize_t
1770  x;
1771 
1772  if (status == MagickFalse)
1773  continue;
1774  q=QueueCacheViewAuthenticPixels(resize_view,0,y,resize_image->columns,1,
1775  exception);
1776  if (q == (Quantum *) NULL)
1777  continue;
1778  offset.y=((double) y+0.5)*scale.y-0.5;
1779  for (x=0; x < (ssize_t) resize_image->columns; x++)
1780  {
1781  register ssize_t
1782  i;
1783 
1784  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1785  {
1786  PixelChannel
1787  channel;
1788 
1789  PixelTrait
1790  resize_traits,
1791  traits;
1792 
1793  channel=GetPixelChannelChannel(image,i);
1794  traits=GetPixelChannelTraits(image,channel);
1795  resize_traits=GetPixelChannelTraits(resize_image,channel);
1796  if ((traits == UndefinedPixelTrait) ||
1797  (resize_traits == UndefinedPixelTrait))
1798  continue;
1799  offset.x=((double) x+0.5)*scale.x-0.5;
1800  status=InterpolatePixelChannels(image,image_view,resize_image,method,
1801  offset.x,offset.y,q,exception);
1802  if (status == MagickFalse)
1803  break;
1804  }
1805  q+=GetPixelChannels(resize_image);
1806  }
1807  if (SyncCacheViewAuthenticPixels(resize_view,exception) == MagickFalse)
1808  status=MagickFalse;
1809  if (image->progress_monitor != (MagickProgressMonitor) NULL)
1810  {
1812  proceed;
1813 
1814 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1815  #pragma omp atomic
1816 #endif
1817  progress++;
1818  proceed=SetImageProgress(image,InterpolativeResizeImageTag,progress,
1819  image->rows);
1820  if (proceed == MagickFalse)
1821  status=MagickFalse;
1822  }
1823  }
1824  resize_view=DestroyCacheView(resize_view);
1825  image_view=DestroyCacheView(image_view);
1826  if (status == MagickFalse)
1827  resize_image=DestroyImage(resize_image);
1828  return(resize_image);
1829 }
1830 #if defined(MAGICKCORE_LQR_DELEGATE)
1831 
1832 /*
1833 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1834 % %
1835 % %
1836 % %
1837 % L i q u i d R e s c a l e I m a g e %
1838 % %
1839 % %
1840 % %
1841 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1842 %
1843 % LiquidRescaleImage() rescales image with seam carving.
1844 %
1845 % The format of the LiquidRescaleImage method is:
1846 %
1847 % Image *LiquidRescaleImage(const Image *image,const size_t columns,
1848 % const size_t rows,const double delta_x,const double rigidity,
1849 % ExceptionInfo *exception)
1850 %
1851 % A description of each parameter follows:
1852 %
1853 % o image: the image.
1854 %
1855 % o columns: the number of columns in the rescaled image.
1856 %
1857 % o rows: the number of rows in the rescaled image.
1858 %
1859 % o delta_x: maximum seam transversal step (0 means straight seams).
1860 %
1861 % o rigidity: introduce a bias for non-straight seams (typically 0).
1862 %
1863 % o exception: return any errors or warnings in this structure.
1864 %
1865 */
1866 MagickExport Image *LiquidRescaleImage(const Image *image,const size_t columns,
1867  const size_t rows,const double delta_x,const double rigidity,
1868  ExceptionInfo *exception)
1869 {
1870 #define LiquidRescaleImageTag "Rescale/Image"
1871 
1872  CacheView
1873  *image_view,
1874  *rescale_view;
1875 
1876  gfloat
1877  *packet,
1878  *pixels;
1879 
1880  Image
1881  *rescale_image;
1882 
1883  int
1884  x_offset,
1885  y_offset;
1886 
1887  LqrCarver
1888  *carver;
1889 
1890  LqrRetVal
1891  lqr_status;
1892 
1894  status;
1895 
1896  MemoryInfo
1897  *pixel_info;
1898 
1899  register gfloat
1900  *q;
1901 
1902  ssize_t
1903  y;
1904 
1905  /*
1906  Liquid rescale image.
1907  */
1908  assert(image != (const Image *) NULL);
1909  assert(image->signature == MagickCoreSignature);
1910  if (image->debug != MagickFalse)
1911  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1912  assert(exception != (ExceptionInfo *) NULL);
1913  assert(exception->signature == MagickCoreSignature);
1914  if ((columns == 0) || (rows == 0))
1915  ThrowImageException(ImageError,"NegativeOrZeroImageSize");
1916  if ((columns == image->columns) && (rows == image->rows))
1917  return(CloneImage(image,0,0,MagickTrue,exception));
1918  if ((columns <= 2) || (rows <= 2))
1919  return(ResizeImage(image,columns,rows,image->filter,exception));
1920  pixel_info=AcquireVirtualMemory(image->columns,image->rows*MaxPixelChannels*
1921  sizeof(*pixels));
1922  if (pixel_info == (MemoryInfo *) NULL)
1923  return((Image *) NULL);
1924  pixels=(gfloat *) GetVirtualMemoryBlob(pixel_info);
1925  status=MagickTrue;
1926  q=pixels;
1927  image_view=AcquireVirtualCacheView(image,exception);
1928  for (y=0; y < (ssize_t) image->rows; y++)
1929  {
1930  register const Quantum
1931  *magick_restrict p;
1932 
1933  register ssize_t
1934  x;
1935 
1936  if (status == MagickFalse)
1937  continue;
1938  p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
1939  if (p == (const Quantum *) NULL)
1940  {
1941  status=MagickFalse;
1942  continue;
1943  }
1944  for (x=0; x < (ssize_t) image->columns; x++)
1945  {
1946  register ssize_t
1947  i;
1948 
1949  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1950  *q++=QuantumScale*p[i];
1951  p+=GetPixelChannels(image);
1952  }
1953  }
1954  image_view=DestroyCacheView(image_view);
1955  carver=lqr_carver_new_ext(pixels,(int) image->columns,(int) image->rows,
1956  (int) GetPixelChannels(image),LQR_COLDEPTH_32F);
1957  if (carver == (LqrCarver *) NULL)
1958  {
1959  pixel_info=RelinquishVirtualMemory(pixel_info);
1960  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
1961  }
1962  lqr_carver_set_preserve_input_image(carver);
1963  lqr_status=lqr_carver_init(carver,(int) delta_x,rigidity);
1964  lqr_status=lqr_carver_resize(carver,(int) columns,(int) rows);
1965  (void) lqr_status;
1966  rescale_image=CloneImage(image,lqr_carver_get_width(carver),
1967  lqr_carver_get_height(carver),MagickTrue,exception);
1968  if (rescale_image == (Image *) NULL)
1969  {
1970  pixel_info=RelinquishVirtualMemory(pixel_info);
1971  return((Image *) NULL);
1972  }
1973  if (SetImageStorageClass(rescale_image,DirectClass,exception) == MagickFalse)
1974  {
1975  pixel_info=RelinquishVirtualMemory(pixel_info);
1976  rescale_image=DestroyImage(rescale_image);
1977  return((Image *) NULL);
1978  }
1979  rescale_view=AcquireAuthenticCacheView(rescale_image,exception);
1980  (void) lqr_carver_scan_reset(carver);
1981  while (lqr_carver_scan_ext(carver,&x_offset,&y_offset,(void **) &packet) != 0)
1982  {
1983  register Quantum
1984  *magick_restrict p;
1985 
1986  register ssize_t
1987  i;
1988 
1989  p=QueueCacheViewAuthenticPixels(rescale_view,x_offset,y_offset,1,1,
1990  exception);
1991  if (p == (Quantum *) NULL)
1992  break;
1993  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
1994  {
1995  PixelChannel
1996  channel;
1997 
1998  PixelTrait
1999  rescale_traits,
2000  traits;
2001 
2002  channel=GetPixelChannelChannel(image,i);
2003  traits=GetPixelChannelTraits(image,channel);
2004  rescale_traits=GetPixelChannelTraits(rescale_image,channel);
2005  if ((traits == UndefinedPixelTrait) ||
2006  (rescale_traits == UndefinedPixelTrait))
2007  continue;
2008  SetPixelChannel(rescale_image,channel,ClampToQuantum(QuantumRange*
2009  packet[i]),p);
2010  }
2011  if (SyncCacheViewAuthenticPixels(rescale_view,exception) == MagickFalse)
2012  break;
2013  }
2014  rescale_view=DestroyCacheView(rescale_view);
2015  pixel_info=RelinquishVirtualMemory(pixel_info);
2016  lqr_carver_destroy(carver);
2017  return(rescale_image);
2018 }
2019 #else
2021  const size_t magick_unused(columns),const size_t magick_unused(rows),
2022  const double magick_unused(delta_x),const double magick_unused(rigidity),
2023  ExceptionInfo *exception)
2024 {
2025  assert(image != (const Image *) NULL);
2026  assert(image->signature == MagickCoreSignature);
2027  if (image->debug != MagickFalse)
2028  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
2029  assert(exception != (ExceptionInfo *) NULL);
2030  assert(exception->signature == MagickCoreSignature);
2032  "DelegateLibrarySupportNotBuiltIn","'%s' (LQR)",image->filename);
2033  return((Image *) NULL);
2034 }
2035 #endif
2036 
2037 /*
2038 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2039 % %
2040 % %
2041 % %
2042 % M a g n i f y I m a g e %
2043 % %
2044 % %
2045 % %
2046 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2047 %
2048 % MagnifyImage() doubles the size of the image with a pixel art scaling
2049 % algorithm.
2050 %
2051 % The format of the MagnifyImage method is:
2052 %
2053 % Image *MagnifyImage(const Image *image,ExceptionInfo *exception)
2054 %
2055 % A description of each parameter follows:
2056 %
2057 % o image: the image.
2058 %
2059 % o exception: return any errors or warnings in this structure.
2060 %
2061 */
2062 
2063 static inline void CopyPixels(const Quantum *source,const ssize_t source_offset,
2064  Quantum *destination,const ssize_t destination_offset,const size_t channels)
2065 {
2066  register ssize_t
2067  i;
2068 
2069  for (i=0; i < (ssize_t) channels; i++)
2070  destination[channels*destination_offset+i]=source[source_offset*channels+i];
2071 }
2072 
2073 static inline void MixPixels(const Quantum *source,const ssize_t *source_offset,
2074  const size_t source_size,Quantum *destination,
2075  const ssize_t destination_offset,const size_t channels)
2076 {
2077  ssize_t
2078  sum;
2079 
2080  register ssize_t
2081  i;
2082 
2083  for (i=0; i < (ssize_t) channels; i++)
2084  {
2085  register ssize_t
2086  j;
2087 
2088  sum=0;
2089  for (j=0; j < (ssize_t) source_size; j++)
2090  sum+=source[source_offset[j]*channels+i];
2091  destination[channels*destination_offset+i]=(Quantum) (sum/source_size);
2092  }
2093 }
2094 
2095 static inline void Mix2Pixels(const Quantum *source,
2096  const ssize_t source_offset1,const ssize_t source_offset2,
2097  Quantum *destination,const ssize_t destination_offset,const size_t channels)
2098 {
2099  const ssize_t
2100  offsets[2] = { source_offset1, source_offset2 };
2101 
2102  MixPixels(source,offsets,2,destination,destination_offset,channels);
2103 }
2104 
2105 static inline int PixelsEqual(const Quantum *source1,ssize_t offset1,
2106  const Quantum *source2,ssize_t offset2,const size_t channels)
2107 {
2108  register ssize_t
2109  i;
2110 
2111  offset1*=channels;
2112  offset2*=channels;
2113  for (i=0; i < (ssize_t) channels; i++)
2114  if (source1[offset1+i] != source2[offset2+i])
2115  return(0);
2116  return(1);
2117 }
2118 
2119 static inline void Eagle2X(const Image *source,const Quantum *pixels,
2120  Quantum *result,const size_t channels)
2121 {
2122  ssize_t
2123  i;
2124 
2125  (void) source;
2126  for (i=0; i < 4; i++)
2127  CopyPixels(pixels,4,result,i,channels);
2128  if (PixelsEqual(pixels,0,pixels,1,channels) &&
2129  PixelsEqual(pixels,1,pixels,3,channels))
2130  CopyPixels(pixels,0,result,0,channels);
2131  if (PixelsEqual(pixels,1,pixels,2,channels) &&
2132  PixelsEqual(pixels,2,pixels,5,channels))
2133  CopyPixels(pixels,2,result,1,channels);
2134  if (PixelsEqual(pixels,3,pixels,6,channels) &&
2135  PixelsEqual(pixels,6,pixels,7,channels))
2136  CopyPixels(pixels,6,result,2,channels);
2137  if (PixelsEqual(pixels,5,pixels,8,channels) &&
2138  PixelsEqual(pixels,8,pixels,7,channels))
2139  CopyPixels(pixels,8,result,3,channels);
2140 }
2141 
2142 static void Hq2XHelper(const unsigned int rule,const Quantum *source,
2143  Quantum *destination,const ssize_t destination_offset,const size_t channels,
2144  const ssize_t e,const ssize_t a,const ssize_t b,const ssize_t d,
2145  const ssize_t f,const ssize_t h)
2146 {
2147 #define caseA(N,A,B,C,D) \
2148  case N: \
2149  { \
2150  const ssize_t \
2151  offsets[4] = { A, B, C, D }; \
2152  \
2153  MixPixels(source,offsets,4,destination,destination_offset,channels);\
2154  break; \
2155  }
2156 #define caseB(N,A,B,C,D,E,F,G,H) \
2157  case N: \
2158  { \
2159  const ssize_t \
2160  offsets[8] = { A, B, C, D, E, F, G, H }; \
2161  \
2162  MixPixels(source,offsets,8,destination,destination_offset,channels);\
2163  break; \
2164  }
2165 
2166  switch (rule)
2167  {
2168  case 0:
2169  {
2170  CopyPixels(source,e,destination,destination_offset,channels);
2171  break;
2172  }
2173  caseA(1,e,e,e,a)
2174  caseA(2,e,e,e,d)
2175  caseA(3,e,e,e,b)
2176  caseA(4,e,e,d,b)
2177  caseA(5,e,e,a,b)
2178  caseA(6,e,e,a,d)
2179  caseB(7,e,e,e,e,e,b,b,d)
2180  caseB(8,e,e,e,e,e,d,d,b)
2181  caseB(9,e,e,e,e,e,e,d,b)
2182  caseB(10,e,e,d,d,d,b,b,b)
2183  case 11:
2184  {
2185  const ssize_t
2186  offsets[16] = { e, e, e, e, e, e, e, e, e, e, e, e, e, e, d, b };
2187 
2188  MixPixels(source,offsets,16,destination,destination_offset,channels);
2189  break;
2190  }
2191  case 12:
2192  {
2193  if (PixelsEqual(source,b,source,d,channels))
2194  {
2195  const ssize_t
2196  offsets[4] = { e, e, d, b };
2197 
2198  MixPixels(source,offsets,4,destination,destination_offset,channels);
2199  }
2200  else
2201  CopyPixels(source,e,destination,destination_offset,channels);
2202  break;
2203  }
2204  case 13:
2205  {
2206  if (PixelsEqual(source,b,source,d,channels))
2207  {
2208  const ssize_t
2209  offsets[8] = { e, e, d, d, d, b, b, b };
2210 
2211  MixPixels(source,offsets,8,destination,destination_offset,channels);
2212  }
2213  else
2214  CopyPixels(source,e,destination,destination_offset,channels);
2215  break;
2216  }
2217  case 14:
2218  {
2219  if (PixelsEqual(source,b,source,d,channels))
2220  {
2221  const ssize_t
2222  offsets[16] = { e, e, e, e, e, e, e, e, e, e, e, e, e, e, d, b };
2223 
2224  MixPixels(source,offsets,16,destination,destination_offset,channels);
2225  }
2226  else
2227  CopyPixels(source,e,destination,destination_offset,channels);
2228  break;
2229  }
2230  case 15:
2231  {
2232  if (PixelsEqual(source,b,source,d,channels))
2233  {
2234  const ssize_t
2235  offsets[4] = { e, e, d, b };
2236 
2237  MixPixels(source,offsets,4,destination,destination_offset,channels);
2238  }
2239  else
2240  {
2241  const ssize_t
2242  offsets[4] = { e, e, e, a };
2243 
2244  MixPixels(source,offsets,4,destination,destination_offset,channels);
2245  }
2246  break;
2247  }
2248  case 16:
2249  {
2250  if (PixelsEqual(source,b,source,d,channels))
2251  {
2252  const ssize_t
2253  offsets[8] = { e, e, e, e, e, e, d, b };
2254 
2255  MixPixels(source,offsets,8,destination,destination_offset,channels);
2256  }
2257  else
2258  {
2259  const ssize_t
2260  offsets[4] = { e, e, e, a };
2261 
2262  MixPixels(source,offsets,4,destination,destination_offset,channels);
2263  }
2264  break;
2265  }
2266  case 17:
2267  {
2268  if (PixelsEqual(source,b,source,d,channels))
2269  {
2270  const ssize_t
2271  offsets[8] = { e, e, d, d, d, b, b, b };
2272 
2273  MixPixels(source,offsets,8,destination,destination_offset,channels);
2274  }
2275  else
2276  {
2277  const ssize_t
2278  offsets[4] = { e, e, e, a };
2279 
2280  MixPixels(source,offsets,4,destination,destination_offset,channels);
2281  }
2282  break;
2283  }
2284  case 18:
2285  {
2286  if (PixelsEqual(source,b,source,f,channels))
2287  {
2288  const ssize_t
2289  offsets[8] = { e, e, e, e, e, b, b, d };
2290 
2291  MixPixels(source,offsets,8,destination,destination_offset,channels);
2292  }
2293  else
2294  {
2295  const ssize_t
2296  offsets[4] = { e, e, e, d };
2297 
2298  MixPixels(source,offsets,4,destination,destination_offset,channels);
2299  }
2300  break;
2301  }
2302  default:
2303  {
2304  if (PixelsEqual(source,d,source,h,channels))
2305  {
2306  const ssize_t
2307  offsets[8] = { e, e, e, e, e, d, d, b };
2308 
2309  MixPixels(source,offsets,8,destination,destination_offset,channels);
2310  }
2311  else
2312  {
2313  const ssize_t
2314  offsets[4] = { e, e, e, b };
2315 
2316  MixPixels(source,offsets,4,destination,destination_offset,channels);
2317  }
2318  break;
2319  }
2320  }
2321  #undef caseA
2322  #undef caseB
2323 }
2324 
2325 static inline unsigned int Hq2XPatternToNumber(const int *pattern)
2326 {
2327  ssize_t
2328  i;
2329 
2330  unsigned int
2331  result,
2332  order;
2333 
2334  result=0;
2335  order=1;
2336  for (i=7; i >= 0; i--)
2337  {
2338  result+=order*pattern[i];
2339  order*=2;
2340  }
2341  return(result);
2342 }
2343 
2344 static inline void Hq2X(const Image *source,const Quantum *pixels,
2345  Quantum *result,const size_t channels)
2346 {
2347  static const unsigned int
2348  Hq2XTable[] =
2349  {
2350  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 15, 12, 5, 3, 17, 13,
2351  4, 4, 6, 18, 4, 4, 6, 18, 5, 3, 12, 12, 5, 3, 1, 12,
2352  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 17, 13, 5, 3, 16, 14,
2353  4, 4, 6, 18, 4, 4, 6, 18, 5, 3, 16, 12, 5, 3, 1, 14,
2354  4, 4, 6, 2, 4, 4, 6, 2, 5, 19, 12, 12, 5, 19, 16, 12,
2355  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 16, 12, 5, 3, 16, 12,
2356  4, 4, 6, 2, 4, 4, 6, 2, 5, 19, 1, 12, 5, 19, 1, 14,
2357  4, 4, 6, 2, 4, 4, 6, 18, 5, 3, 16, 12, 5, 19, 1, 14,
2358  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 15, 12, 5, 3, 17, 13,
2359  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 16, 12, 5, 3, 16, 12,
2360  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 17, 13, 5, 3, 16, 14,
2361  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 16, 13, 5, 3, 1, 14,
2362  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 16, 12, 5, 3, 16, 13,
2363  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 16, 12, 5, 3, 1, 12,
2364  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 16, 12, 5, 3, 1, 14,
2365  4, 4, 6, 2, 4, 4, 6, 2, 5, 3, 1, 12, 5, 3, 1, 14
2366  };
2367 
2368  const int
2369  pattern1[] =
2370  {
2371  !PixelsEqual(pixels,4,pixels,8,channels),
2372  !PixelsEqual(pixels,4,pixels,7,channels),
2373  !PixelsEqual(pixels,4,pixels,6,channels),
2374  !PixelsEqual(pixels,4,pixels,5,channels),
2375  !PixelsEqual(pixels,4,pixels,3,channels),
2376  !PixelsEqual(pixels,4,pixels,2,channels),
2377  !PixelsEqual(pixels,4,pixels,1,channels),
2378  !PixelsEqual(pixels,4,pixels,0,channels)
2379  };
2380 
2381 #define Rotated(p) p[2], p[4], p[7], p[1], p[6], p[0], p[3], p[5]
2382  const int pattern2[] = { Rotated(pattern1) };
2383  const int pattern3[] = { Rotated(pattern2) };
2384  const int pattern4[] = { Rotated(pattern3) };
2385 #undef Rotated
2386 
2387  Hq2XHelper(Hq2XTable[Hq2XPatternToNumber(pattern1)],pixels,result,0,
2388  channels,4,0,1,3,5,7);
2389  Hq2XHelper(Hq2XTable[Hq2XPatternToNumber(pattern2)],pixels,result,1,
2390  channels,4,2,5,1,7,3);
2391  Hq2XHelper(Hq2XTable[Hq2XPatternToNumber(pattern3)],pixels,result,3,
2392  channels,4,8,7,5,3,1);
2393  Hq2XHelper(Hq2XTable[Hq2XPatternToNumber(pattern4)],pixels,result,2,
2394  channels,4,6,3,7,1,5);
2395 }
2396 
2397 static void Fish2X(const Image *source,const Quantum *pixels,Quantum *result,
2398  const size_t channels)
2399 {
2400 #define Corner(A,B,C,D) \
2401  { \
2402  if (intensities[B] > intensities[A]) \
2403  { \
2404  ssize_t \
2405  offsets[3] = { B, C, D }; \
2406  \
2407  MixPixels(pixels,offsets,3,result,3,channels); \
2408  } \
2409  else \
2410  { \
2411  ssize_t \
2412  offsets[3] = { A, B, C }; \
2413  \
2414  MixPixels(pixels,offsets,3,result,3,channels); \
2415  } \
2416  }
2417 
2418 #define Line(A,B,C,D) \
2419  { \
2420  if (intensities[C] > intensities[A]) \
2421  Mix2Pixels(pixels,C,D,result,3,channels); \
2422  else \
2423  Mix2Pixels(pixels,A,B,result,3,channels); \
2424  }
2425 
2427  intensities[9];
2428 
2429  int
2430  ae,
2431  bd,
2432  ab,
2433  ad,
2434  be,
2435  de;
2436 
2437  register ssize_t
2438  i;
2439 
2440  ssize_t
2441  offsets[4] = { 0, 1, 3, 4 };
2442 
2443  for (i=0; i < 9; i++)
2444  intensities[i]=GetPixelIntensity(source,pixels + i*channels);
2445  CopyPixels(pixels,0,result,0,channels);
2446  CopyPixels(pixels,(ssize_t) (intensities[0] > intensities[1] ? 0 : 1),result,
2447  1,channels);
2448  CopyPixels(pixels,(ssize_t) (intensities[0] > intensities[3] ? 0 : 3),result,
2449  2,channels);
2450  ae=PixelsEqual(pixels,0,pixels,4,channels);
2451  bd=PixelsEqual(pixels,1,pixels,3,channels);
2452  ab=PixelsEqual(pixels,0,pixels,1,channels);
2453  de=PixelsEqual(pixels,3,pixels,4,channels);
2454  ad=PixelsEqual(pixels,0,pixels,3,channels);
2455  be=PixelsEqual(pixels,1,pixels,4,channels);
2456  if (ae && bd && ab)
2457  {
2458  CopyPixels(pixels,0,result,3,channels);
2459  return;
2460  }
2461  if (ad && de && !ab)
2462  {
2463  Corner(1,0,4,3)
2464  return;
2465  }
2466  if (be && de && !ab)
2467  {
2468  Corner(0,1,3,4)
2469  return;
2470  }
2471  if (ad && ab && !be)
2472  {
2473  Corner(4,3,1,0)
2474  return;
2475  }
2476  if (ab && be && !ad)
2477  {
2478  Corner(3,0,4,1)
2479  return;
2480  }
2481  if (ae && (!bd || intensities[1] > intensities[0]))
2482  {
2483  Mix2Pixels(pixels,0,4,result,3,channels);
2484  return;
2485  }
2486  if (bd && (!ae || intensities[0] > intensities[1]))
2487  {
2488  Mix2Pixels(pixels,1,3,result,3,channels);
2489  return;
2490  }
2491  if (ab)
2492  {
2493  Line(0,1,3,4)
2494  return;
2495  }
2496  if (de)
2497  {
2498  Line(3,4,0,1)
2499  return;
2500  }
2501  if (ad)
2502  {
2503  Line(0,3,1,4)
2504  return;
2505  }
2506  if (be)
2507  {
2508  Line(1,4,0,3)
2509  return;
2510  }
2511  MixPixels(pixels,offsets,4,result,3,channels);
2512 #undef Corner
2513 #undef Line
2514 }
2515 
2516 static void Xbr2X(const Image *source,const Quantum *pixels,Quantum *result,
2517  const size_t channels)
2518 {
2519 #define WeightVar(M,N) const int w_##M##_##N = \
2520  PixelsEqual(pixels,M,pixels,N,channels) ? 0 : 1;
2521 
2522  WeightVar(12,11)
2523  WeightVar(12,7)
2524  WeightVar(12,13)
2525  WeightVar(12,17)
2526  WeightVar(12,16)
2527  WeightVar(12,8)
2528  WeightVar(6,10)
2529  WeightVar(6,2)
2530  WeightVar(11,7)
2531  WeightVar(11,17)
2532  WeightVar(11,5)
2533  WeightVar(7,13)
2534  WeightVar(7,1)
2535  WeightVar(12,6)
2536  WeightVar(12,18)
2537  WeightVar(8,14)
2538  WeightVar(8,2)
2539  WeightVar(13,17)
2540  WeightVar(13,9)
2541  WeightVar(7,3)
2542  WeightVar(16,10)
2543  WeightVar(16,22)
2544  WeightVar(17,21)
2545  WeightVar(11,15)
2546  WeightVar(18,14)
2547  WeightVar(18,22)
2548  WeightVar(17,23)
2549  WeightVar(17,19)
2550 #undef WeightVar
2551 
2552  if (
2553  w_12_16 + w_12_8 + w_6_10 + w_6_2 + (4 * w_11_7) <
2554  w_11_17 + w_11_5 + w_7_13 + w_7_1 + (4 * w_12_6)
2555  )
2556  Mix2Pixels(pixels,(ssize_t) (w_12_11 <= w_12_7 ? 11 : 7),12,result,0,
2557  channels);
2558  else
2559  CopyPixels(pixels,12,result,0,channels);
2560  if (
2561  w_12_18 + w_12_6 + w_8_14 + w_8_2 + (4 * w_7_13) <
2562  w_13_17 + w_13_9 + w_11_7 + w_7_3 + (4 * w_12_8)
2563  )
2564  Mix2Pixels(pixels,(ssize_t) (w_12_7 <= w_12_13 ? 7 : 13),12,result,1,
2565  channels);
2566  else
2567  CopyPixels(pixels,12,result,1,channels);
2568  if (
2569  w_12_6 + w_12_18 + w_16_10 + w_16_22 + (4 * w_11_17) <
2570  w_11_7 + w_11_15 + w_13_17 + w_17_21 + (4 * w_12_16)
2571  )
2572  Mix2Pixels(pixels,(ssize_t) (w_12_11 <= w_12_17 ? 11 : 17),12,result,2,
2573  channels);
2574  else
2575  CopyPixels(pixels,12,result,2,channels);
2576  if (
2577  w_12_8 + w_12_16 + w_18_14 + w_18_22 + (4 * w_13_17) <
2578  w_11_17 + w_17_23 + w_17_19 + w_7_13 + (4 * w_12_18)
2579  )
2580  Mix2Pixels(pixels,(ssize_t) (w_12_13 <= w_12_17 ? 13 : 17),12,result,3,
2581  channels);
2582  else
2583  CopyPixels(pixels,12,result,3,channels);
2584 }
2585 
2586 static void Scale2X(const Image *source,const Quantum *pixels,Quantum *result,
2587  const size_t channels)
2588 {
2589  if (PixelsEqual(pixels,1,pixels,7,channels) ||
2590  PixelsEqual(pixels,3,pixels,5,channels))
2591  {
2592  register ssize_t
2593  i;
2594 
2595  for (i=0; i < 4; i++)
2596  CopyPixels(pixels,4,result,i,channels);
2597  return;
2598  }
2599  if (PixelsEqual(pixels,1,pixels,3,channels))
2600  CopyPixels(pixels,3,result,0,channels);
2601  else
2602  CopyPixels(pixels,4,result,0,channels);
2603  if (PixelsEqual(pixels,1,pixels,5,channels))
2604  CopyPixels(pixels,5,result,1,channels);
2605  else
2606  CopyPixels(pixels,4,result,1,channels);
2607  if (PixelsEqual(pixels,3,pixels,7,channels))
2608  CopyPixels(pixels,3,result,2,channels);
2609  else
2610  CopyPixels(pixels,4,result,2,channels);
2611  if (PixelsEqual(pixels,5,pixels,7,channels))
2612  CopyPixels(pixels,5,result,3,channels);
2613  else
2614  CopyPixels(pixels,4,result,3,channels);
2615 }
2616 
2617 static void Epbx2X(const Image *source,const Quantum *pixels,
2618  Quantum *result,const size_t channels)
2619 {
2620 #define HelperCond(a,b,c,d,e,f,g) ( \
2621  PixelsEqual(pixels,a,pixels,b,channels) && ( \
2622  PixelsEqual(pixels,c,pixels,d,channels) || \
2623  PixelsEqual(pixels,c,pixels,e,channels) || \
2624  PixelsEqual(pixels,a,pixels,f,channels) || \
2625  PixelsEqual(pixels,b,pixels,g,channels) \
2626  ) \
2627  )
2628 
2629  register ssize_t
2630  i;
2631 
2632  for (i=0; i < 4; i++)
2633  CopyPixels(pixels,4,result,i,channels);
2634  if (
2635  !PixelsEqual(pixels,3,pixels,5,channels) &&
2636  !PixelsEqual(pixels,1,pixels,7,channels) &&
2637  (
2638  PixelsEqual(pixels,4,pixels,3,channels) ||
2639  PixelsEqual(pixels,4,pixels,7,channels) ||
2640  PixelsEqual(pixels,4,pixels,5,channels) ||
2641  PixelsEqual(pixels,4,pixels,1,channels) ||
2642  (
2643  (
2644  !PixelsEqual(pixels,0,pixels,8,channels) ||
2645  PixelsEqual(pixels,4,pixels,6,channels) ||
2646  PixelsEqual(pixels,3,pixels,2,channels)
2647  ) &&
2648  (
2649  !PixelsEqual(pixels,6,pixels,2,channels) ||
2650  PixelsEqual(pixels,4,pixels,0,channels) ||
2651  PixelsEqual(pixels,4,pixels,8,channels)
2652  )
2653  )
2654  )
2655  )
2656  {
2657  if (HelperCond(1,3,4,0,8,2,6))
2658  Mix2Pixels(pixels,1,3,result,0,channels);
2659  if (HelperCond(5,1,4,2,6,8,0))
2660  Mix2Pixels(pixels,5,1,result,1,channels);
2661  if (HelperCond(3,7,4,6,2,0,8))
2662  Mix2Pixels(pixels,3,7,result,2,channels);
2663  if (HelperCond(7,5,4,8,0,6,2))
2664  Mix2Pixels(pixels,7,5,result,3,channels);
2665  }
2666 
2667 #undef HelperCond
2668 }
2669 
2670 static inline void Eagle3X(const Image *source,const Quantum *pixels,
2671  Quantum *result,const size_t channels)
2672 {
2673  ssize_t
2674  corner_tl,
2675  corner_tr,
2676  corner_bl,
2677  corner_br;
2678 
2679  corner_tl=PixelsEqual(pixels,0,pixels,1,channels) &&
2680  PixelsEqual(pixels,0,pixels,3,channels);
2681  corner_tr=PixelsEqual(pixels,1,pixels,2,channels) &&
2682  PixelsEqual(pixels,2,pixels,5,channels);
2683  corner_bl=PixelsEqual(pixels,3,pixels,6,channels) &&
2684  PixelsEqual(pixels,6,pixels,7,channels);
2685  corner_br=PixelsEqual(pixels,5,pixels,7,channels) &&
2686  PixelsEqual(pixels,7,pixels,8,channels);
2687  CopyPixels(pixels,(ssize_t) (corner_tl ? 0 : 4),result,0,channels);
2688  if (corner_tl && corner_tr)
2689  Mix2Pixels(pixels,0,2,result,1,channels);
2690  else
2691  CopyPixels(pixels,4,result,1,channels);
2692  CopyPixels(pixels,(ssize_t) (corner_tr ? 1 : 4),result,2,channels);
2693  if (corner_tl && corner_bl)
2694  Mix2Pixels(pixels,0,6,result,3,channels);
2695  else
2696  CopyPixels(pixels,4,result,3,channels);
2697  CopyPixels(pixels,4,result,4,channels);
2698  if (corner_tr && corner_br)
2699  Mix2Pixels(pixels,2,8,result,5,channels);
2700  else
2701  CopyPixels(pixels,4,result,5,channels);
2702  CopyPixels(pixels,(ssize_t) (corner_bl ? 3 : 4),result,6,channels);
2703  if (corner_bl && corner_br)
2704  Mix2Pixels(pixels,6,8,result,7,channels);
2705  else
2706  CopyPixels(pixels,4,result,7,channels);
2707  CopyPixels(pixels,(ssize_t) (corner_br ? 5 : 4),result,8,channels);
2708 }
2709 
2710 static inline void Eagle3XB(const Image *source,const Quantum *pixels,
2711  Quantum *result,const size_t channels)
2712 {
2713  ssize_t
2714  corner_tl,
2715  corner_tr,
2716  corner_bl,
2717  corner_br;
2718 
2719  corner_tl=PixelsEqual(pixels,0,pixels,1,channels) &&
2720  PixelsEqual(pixels,0,pixels,3,channels);
2721  corner_tr=PixelsEqual(pixels,1,pixels,2,channels) &&
2722  PixelsEqual(pixels,2,pixels,5,channels);
2723  corner_bl=PixelsEqual(pixels,3,pixels,6,channels) &&
2724  PixelsEqual(pixels,6,pixels,7,channels);
2725  corner_br=PixelsEqual(pixels,5,pixels,7,channels) &&
2726  PixelsEqual(pixels,7,pixels,8,channels);
2727  CopyPixels(pixels,(ssize_t) (corner_tl ? 0 : 4),result,0,channels);
2728  CopyPixels(pixels,4,result,1,channels);
2729  CopyPixels(pixels,(ssize_t) (corner_tr ? 1 : 4),result,2,channels);
2730  CopyPixels(pixels,4,result,3,channels);
2731  CopyPixels(pixels,4,result,4,channels);
2732  CopyPixels(pixels,4,result,5,channels);
2733  CopyPixels(pixels,(ssize_t) (corner_bl ? 3 : 4),result,6,channels);
2734  CopyPixels(pixels,4,result,7,channels);
2735  CopyPixels(pixels,(ssize_t) (corner_br ? 5 : 4),result,8,channels);
2736 }
2737 
2738 static inline void Scale3X(const Image *source,const Quantum *pixels,
2739  Quantum *result,const size_t channels)
2740 {
2741  if (!PixelsEqual(pixels,1,pixels,7,channels) &&
2742  !PixelsEqual(pixels,3,pixels,5,channels))
2743  {
2744  if (PixelsEqual(pixels,3,pixels,1,channels))
2745  CopyPixels(pixels,3,result,0,channels);
2746  else
2747  CopyPixels(pixels,4,result,0,channels);
2748 
2749  if (
2750  (
2751  PixelsEqual(pixels,3,pixels,1,channels) &&
2752  !PixelsEqual(pixels,4,pixels,2,channels)
2753  ) ||
2754  (
2755  PixelsEqual(pixels,5,pixels,1,channels) &&
2756  !PixelsEqual(pixels,4,pixels,0,channels)
2757  )
2758  )
2759  CopyPixels(pixels,1,result,1,channels);
2760  else
2761  CopyPixels(pixels,4,result,1,channels);
2762  if (PixelsEqual(pixels,5,pixels,1,channels))
2763  CopyPixels(pixels,5,result,2,channels);
2764  else
2765  CopyPixels(pixels,4,result,2,channels);
2766  if (
2767  (
2768  PixelsEqual(pixels,3,pixels,1,channels) &&
2769  !PixelsEqual(pixels,4,pixels,6,channels)
2770  ) ||
2771  (
2772  PixelsEqual(pixels,3,pixels,7,channels) &&
2773  !PixelsEqual(pixels,4,pixels,0,channels)
2774  )
2775  )
2776  CopyPixels(pixels,3,result,3,channels);
2777  else
2778  CopyPixels(pixels,4,result,3,channels);
2779  CopyPixels(pixels,4,result,4,channels);
2780  if (
2781  (
2782  PixelsEqual(pixels,5,pixels,1,channels) &&
2783  !PixelsEqual(pixels,4,pixels,8,channels)
2784  ) ||
2785  (
2786  PixelsEqual(pixels,5,pixels,7,channels) &&
2787  !PixelsEqual(pixels,4,pixels,2,channels)
2788  )
2789  )
2790  CopyPixels(pixels,5,result,5,channels);
2791  else
2792  CopyPixels(pixels,4,result,5,channels);
2793  if (PixelsEqual(pixels,3,pixels,7,channels))
2794  CopyPixels(pixels,3,result,6,channels);
2795  else
2796  CopyPixels(pixels,4,result,6,channels);
2797  if (
2798  (
2799  PixelsEqual(pixels,3,pixels,7,channels) &&
2800  !PixelsEqual(pixels,4,pixels,8,channels)
2801  ) ||
2802  (
2803  PixelsEqual(pixels,5,pixels,7,channels) &&
2804  !PixelsEqual(pixels,4,pixels,6,channels)
2805  )
2806  )
2807  CopyPixels(pixels,7,result,7,channels);
2808  else
2809  CopyPixels(pixels,4,result,7,channels);
2810  if (PixelsEqual(pixels,5,pixels,7,channels))
2811  CopyPixels(pixels,5,result,8,channels);
2812  else
2813  CopyPixels(pixels,4,result,8,channels);
2814  }
2815  else
2816  {
2817  register ssize_t
2818  i;
2819 
2820  for (i=0; i < 9; i++)
2821  CopyPixels(pixels,4,result,i,channels);
2822  }
2823 }
2824 
2826 {
2827 #define MagnifyImageTag "Magnify/Image"
2828 
2829  CacheView
2830  *image_view,
2831  *magnify_view;
2832 
2833  const char
2834  *option;
2835 
2836  Image
2837  *source_image,
2838  *magnify_image;
2839 
2841  status;
2842 
2844  progress;
2845 
2846  OffsetInfo
2847  offset;
2848 
2850  rectangle;
2851 
2852  ssize_t
2853  y;
2854 
2855  unsigned char
2856  magnification,
2857  width;
2858 
2859  void
2860  (*scaling_method)(const Image *,const Quantum *,Quantum *,size_t);
2861 
2862  /*
2863  Initialize magnified image attributes.
2864  */
2865  assert(image != (const Image *) NULL);
2866  assert(image->signature == MagickCoreSignature);
2867  if (image->debug != MagickFalse)
2868  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
2869  assert(exception != (ExceptionInfo *) NULL);
2870  assert(exception->signature == MagickCoreSignature);
2871  option=GetImageOption(image->image_info,"magnify:method");
2872  if (option == (char *) NULL)
2873  option="scale2x";
2874  scaling_method=Scale2X;
2875  magnification=1;
2876  width=1;
2877  switch (*option)
2878  {
2879  case 'e':
2880  {
2881  if (LocaleCompare(option,"eagle2x") == 0)
2882  {
2883  scaling_method=Eagle2X;
2884  magnification=2;
2885  width=3;
2886  break;
2887  }
2888  if (LocaleCompare(option,"eagle3x") == 0)
2889  {
2890  scaling_method=Eagle3X;
2891  magnification=3;
2892  width=3;
2893  break;
2894  }
2895  if (LocaleCompare(option,"eagle3xb") == 0)
2896  {
2897  scaling_method=Eagle3XB;
2898  magnification=3;
2899  width=3;
2900  break;
2901  }
2902  if (LocaleCompare(option,"epbx2x") == 0)
2903  {
2904  scaling_method=Epbx2X;
2905  magnification=2;
2906  width=3;
2907  break;
2908  }
2909  break;
2910  }
2911  case 'f':
2912  {
2913  if (LocaleCompare(option,"fish2x") == 0)
2914  {
2915  scaling_method=Fish2X;
2916  magnification=2;
2917  width=3;
2918  break;
2919  }
2920  break;
2921  }
2922  case 'h':
2923  {
2924  if (LocaleCompare(option,"hq2x") == 0)
2925  {
2926  scaling_method=Hq2X;
2927  magnification=2;
2928  width=3;
2929  break;
2930  }
2931  break;
2932  }
2933  case 's':
2934  {
2935  if (LocaleCompare(option,"scale2x") == 0)
2936  {
2937  scaling_method=Scale2X;
2938  magnification=2;
2939  width=3;
2940  break;
2941  }
2942  if (LocaleCompare(option,"scale3x") == 0)
2943  {
2944  scaling_method=Scale3X;
2945  magnification=3;
2946  width=3;
2947  break;
2948  }
2949  break;
2950  }
2951  case 'x':
2952  {
2953  if (LocaleCompare(option,"xbr2x") == 0)
2954  {
2955  scaling_method=Xbr2X;
2956  magnification=2;
2957  width=5;
2958  }
2959  break;
2960  }
2961  default:
2962  break;
2963  }
2964  /*
2965  Make a working copy of the source image and convert it to RGB colorspace.
2966  */
2967  source_image=CloneImage(image,image->columns,image->rows,MagickTrue,
2968  exception);
2969  offset.x=0;
2970  offset.y=0;
2971  rectangle.x=0;
2972  rectangle.y=0;
2973  rectangle.width=image->columns;
2974  rectangle.height=image->rows;
2975  (void) CopyImagePixels(source_image,image,&rectangle,&offset,exception);
2976  (void) SetImageColorspace(source_image,RGBColorspace,exception);
2977  magnify_image=CloneImage(source_image,magnification*source_image->columns,
2978  magnification*source_image->rows,MagickTrue,exception);
2979  if (magnify_image == (Image *) NULL)
2980  return((Image *) NULL);
2981  /*
2982  Magnify the image.
2983  */
2984  status=MagickTrue;
2985  progress=0;
2986  image_view=AcquireVirtualCacheView(source_image,exception);
2987  magnify_view=AcquireAuthenticCacheView(magnify_image,exception);
2988 #if defined(MAGICKCORE_OPENMP_SUPPORT)
2989  #pragma omp parallel for schedule(static) shared(progress,status) \
2990  magick_number_threads(source_image,magnify_image,source_image->rows,1)
2991 #endif
2992  for (y=0; y < (ssize_t) source_image->rows; y++)
2993  {
2994  Quantum
2995  r[128]; /* to hold result pixels */
2996 
2997  register Quantum
2998  *magick_restrict q;
2999 
3000  register ssize_t
3001  x;
3002 
3003  if (status == MagickFalse)
3004  continue;
3005  q=QueueCacheViewAuthenticPixels(magnify_view,0,magnification*y,
3006  magnify_image->columns,magnification,exception);
3007  if (q == (Quantum *) NULL)
3008  {
3009  status=MagickFalse;
3010  continue;
3011  }
3012  /*
3013  Magnify this row of pixels.
3014  */
3015  for (x=0; x < (ssize_t) source_image->columns; x++)
3016  {
3017  register const Quantum
3018  *magick_restrict p;
3019 
3020  size_t
3021  channels;
3022 
3023  register ssize_t
3024  i;
3025 
3026  ssize_t
3027  j;
3028 
3029  p=GetCacheViewVirtualPixels(image_view,x-width/2,y-width/2,width,width,
3030  exception);
3031  channels=GetPixelChannels(source_image);
3032  scaling_method(source_image,p,r,channels);
3033  /*
3034  Copy the result pixels into the final image.
3035  */
3036  for (j=0; j < (ssize_t) magnification; j++)
3037  for (i=0; i < (ssize_t) (channels*magnification); i++)
3038  q[j*channels*magnify_image->columns+i]=r[j*magnification*channels+i];
3039  q+=magnification*GetPixelChannels(magnify_image);
3040  }
3041  if (SyncCacheViewAuthenticPixels(magnify_view,exception) == MagickFalse)
3042  status=MagickFalse;
3043  if (image->progress_monitor != (MagickProgressMonitor) NULL)
3044  {
3046  proceed;
3047 
3048 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3049  #pragma omp atomic
3050 #endif
3051  progress++;
3052  proceed=SetImageProgress(image,MagnifyImageTag,progress,image->rows);
3053  if (proceed == MagickFalse)
3054  status=MagickFalse;
3055  }
3056  }
3057  magnify_view=DestroyCacheView(magnify_view);
3058  image_view=DestroyCacheView(image_view);
3059  source_image=DestroyImage(source_image);
3060  if (status == MagickFalse)
3061  magnify_image=DestroyImage(magnify_image);
3062  return(magnify_image);
3063 }
3064 
3065 /*
3066 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3067 % %
3068 % %
3069 % %
3070 % M i n i f y I m a g e %
3071 % %
3072 % %
3073 % %
3074 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3075 %
3076 % MinifyImage() is a convenience method that scales an image proportionally to
3077 % half its size.
3078 %
3079 % The format of the MinifyImage method is:
3080 %
3081 % Image *MinifyImage(const Image *image,ExceptionInfo *exception)
3082 %
3083 % A description of each parameter follows:
3084 %
3085 % o image: the image.
3086 %
3087 % o exception: return any errors or warnings in this structure.
3088 %
3089 */
3091 {
3092  Image
3093  *minify_image;
3094 
3095  assert(image != (Image *) NULL);
3096  assert(image->signature == MagickCoreSignature);
3097  if (image->debug != MagickFalse)
3098  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
3099  assert(exception != (ExceptionInfo *) NULL);
3100  assert(exception->signature == MagickCoreSignature);
3101  minify_image=ResizeImage(image,image->columns/2,image->rows/2,SplineFilter,
3102  exception);
3103  return(minify_image);
3104 }
3105 
3106 /*
3107 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3108 % %
3109 % %
3110 % %
3111 % R e s a m p l e I m a g e %
3112 % %
3113 % %
3114 % %
3115 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3116 %
3117 % ResampleImage() resize image in terms of its pixel size, so that when
3118 % displayed at the given resolution it will be the same size in terms of
3119 % real world units as the original image at the original resolution.
3120 %
3121 % The format of the ResampleImage method is:
3122 %
3123 % Image *ResampleImage(Image *image,const double x_resolution,
3124 % const double y_resolution,const FilterType filter,
3125 % ExceptionInfo *exception)
3126 %
3127 % A description of each parameter follows:
3128 %
3129 % o image: the image to be resized to fit the given resolution.
3130 %
3131 % o x_resolution: the new image x resolution.
3132 %
3133 % o y_resolution: the new image y resolution.
3134 %
3135 % o filter: Image filter to use.
3136 %
3137 % o exception: return any errors or warnings in this structure.
3138 %
3139 */
3140 MagickExport Image *ResampleImage(const Image *image,const double x_resolution,
3141  const double y_resolution,const FilterType filter,ExceptionInfo *exception)
3142 {
3143 #define ResampleImageTag "Resample/Image"
3144 
3145  Image
3146  *resample_image;
3147 
3148  size_t
3149  height,
3150  width;
3151 
3152  /*
3153  Initialize sampled image attributes.
3154  */
3155  assert(image != (const Image *) NULL);
3156  assert(image->signature == MagickCoreSignature);
3157  if (image->debug != MagickFalse)
3158  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
3159  assert(exception != (ExceptionInfo *) NULL);
3160  assert(exception->signature == MagickCoreSignature);
3161  width=(size_t) (x_resolution*image->columns/(image->resolution.x == 0.0 ?
3162  72.0 : image->resolution.x)+0.5);
3163  height=(size_t) (y_resolution*image->rows/(image->resolution.y == 0.0 ?
3164  72.0 : image->resolution.y)+0.5);
3165  resample_image=ResizeImage(image,width,height,filter,exception);
3166  if (resample_image != (Image *) NULL)
3167  {
3168  resample_image->resolution.x=x_resolution;
3169  resample_image->resolution.y=y_resolution;
3170  }
3171  return(resample_image);
3172 }
3173 
3174 /*
3175 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3176 % %
3177 % %
3178 % %
3179 % R e s i z e I m a g e %
3180 % %
3181 % %
3182 % %
3183 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3184 %
3185 % ResizeImage() scales an image to the desired dimensions, using the given
3186 % filter (see AcquireFilterInfo()).
3187 %
3188 % If an undefined filter is given the filter defaults to Mitchell for a
3189 % colormapped image, a image with a matte channel, or if the image is
3190 % enlarged. Otherwise the filter defaults to a Lanczos.
3191 %
3192 % ResizeImage() was inspired by Paul Heckbert's "zoom" program.
3193 %
3194 % The format of the ResizeImage method is:
3195 %
3196 % Image *ResizeImage(Image *image,const size_t columns,const size_t rows,
3197 % const FilterType filter,ExceptionInfo *exception)
3198 %
3199 % A description of each parameter follows:
3200 %
3201 % o image: the image.
3202 %
3203 % o columns: the number of columns in the scaled image.
3204 %
3205 % o rows: the number of rows in the scaled image.
3206 %
3207 % o filter: Image filter to use.
3208 %
3209 % o exception: return any errors or warnings in this structure.
3210 %
3211 */
3212 
3213 typedef struct _ContributionInfo
3214 {
3215  double
3217 
3218  ssize_t
3221 
3223  ContributionInfo **contribution)
3224 {
3225  register ssize_t
3226  i;
3227 
3228  assert(contribution != (ContributionInfo **) NULL);
3229  for (i=0; i < (ssize_t) GetMagickResourceLimit(ThreadResource); i++)
3230  if (contribution[i] != (ContributionInfo *) NULL)
3231  contribution[i]=(ContributionInfo *) RelinquishAlignedMemory(
3232  contribution[i]);
3233  contribution=(ContributionInfo **) RelinquishMagickMemory(contribution);
3234  return(contribution);
3235 }
3236 
3238 {
3239  register ssize_t
3240  i;
3241 
3243  **contribution;
3244 
3245  size_t
3246  number_threads;
3247 
3248  number_threads=(size_t) GetMagickResourceLimit(ThreadResource);
3249  contribution=(ContributionInfo **) AcquireQuantumMemory(number_threads,
3250  sizeof(*contribution));
3251  if (contribution == (ContributionInfo **) NULL)
3252  return((ContributionInfo **) NULL);
3253  (void) memset(contribution,0,number_threads*sizeof(*contribution));
3254  for (i=0; i < (ssize_t) number_threads; i++)
3255  {
3256  contribution[i]=(ContributionInfo *) MagickAssumeAligned(
3257  AcquireAlignedMemory(count,sizeof(**contribution)));
3258  if (contribution[i] == (ContributionInfo *) NULL)
3259  return(DestroyContributionThreadSet(contribution));
3260  }
3261  return(contribution);
3262 }
3263 
3265  const ResizeFilter *magick_restrict resize_filter,
3266  const Image *magick_restrict image,Image *magick_restrict resize_image,
3267  const double x_factor,const MagickSizeType span,
3268  MagickOffsetType *magick_restrict progress,ExceptionInfo *exception)
3269 {
3270 #define ResizeImageTag "Resize/Image"
3271 
3272  CacheView
3273  *image_view,
3274  *resize_view;
3275 
3276  ClassType
3277  storage_class;
3278 
3280  **magick_restrict contributions;
3281 
3283  status;
3284 
3285  double
3286  scale,
3287  support;
3288 
3289  ssize_t
3290  x;
3291 
3292  /*
3293  Apply filter to resize horizontally from image to resize image.
3294  */
3295  scale=MagickMax(1.0/x_factor+MagickEpsilon,1.0);
3296  support=scale*GetResizeFilterSupport(resize_filter);
3297  storage_class=support > 0.5 ? DirectClass : image->storage_class;
3298  if (SetImageStorageClass(resize_image,storage_class,exception) == MagickFalse)
3299  return(MagickFalse);
3300  if (support < 0.5)
3301  {
3302  /*
3303  Support too small even for nearest neighbour: Reduce to point sampling.
3304  */
3305  support=(double) 0.5;
3306  scale=1.0;
3307  }
3308  contributions=AcquireContributionThreadSet((size_t) (2.0*support+3.0));
3309  if (contributions == (ContributionInfo **) NULL)
3310  {
3311  (void) ThrowMagickException(exception,GetMagickModule(),
3312  ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
3313  return(MagickFalse);
3314  }
3315  status=MagickTrue;
3316  scale=PerceptibleReciprocal(scale);
3317  image_view=AcquireVirtualCacheView(image,exception);
3318  resize_view=AcquireAuthenticCacheView(resize_image,exception);
3319 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3320  #pragma omp parallel for schedule(static) shared(progress,status) \
3321  magick_number_threads(image,resize_image,resize_image->columns,1)
3322 #endif
3323  for (x=0; x < (ssize_t) resize_image->columns; x++)
3324  {
3325  const int
3326  id = GetOpenMPThreadId();
3327 
3328  double
3329  bisect,
3330  density;
3331 
3332  register const Quantum
3333  *magick_restrict p;
3334 
3335  register ContributionInfo
3336  *magick_restrict contribution;
3337 
3338  register Quantum
3339  *magick_restrict q;
3340 
3341  register ssize_t
3342  y;
3343 
3344  ssize_t
3345  n,
3346  start,
3347  stop;
3348 
3349  if (status == MagickFalse)
3350  continue;
3351  bisect=(double) (x+0.5)/x_factor+MagickEpsilon;
3352  start=(ssize_t) MagickMax(bisect-support+0.5,0.0);
3353  stop=(ssize_t) MagickMin(bisect+support+0.5,(double) image->columns);
3354  density=0.0;
3355  contribution=contributions[id];
3356  for (n=0; n < (stop-start); n++)
3357  {
3358  contribution[n].pixel=start+n;
3359  contribution[n].weight=GetResizeFilterWeight(resize_filter,scale*
3360  ((double) (start+n)-bisect+0.5));
3361  density+=contribution[n].weight;
3362  }
3363  if (n == 0)
3364  continue;
3365  if ((density != 0.0) && (density != 1.0))
3366  {
3367  register ssize_t
3368  i;
3369 
3370  /*
3371  Normalize.
3372  */
3373  density=PerceptibleReciprocal(density);
3374  for (i=0; i < n; i++)
3375  contribution[i].weight*=density;
3376  }
3377  p=GetCacheViewVirtualPixels(image_view,contribution[0].pixel,0,(size_t)
3378  (contribution[n-1].pixel-contribution[0].pixel+1),image->rows,exception);
3379  q=QueueCacheViewAuthenticPixels(resize_view,x,0,1,resize_image->rows,
3380  exception);
3381  if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
3382  {
3383  status=MagickFalse;
3384  continue;
3385  }
3386  for (y=0; y < (ssize_t) resize_image->rows; y++)
3387  {
3388  register ssize_t
3389  i;
3390 
3391  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
3392  {
3393  double
3394  alpha,
3395  gamma,
3396  pixel;
3397 
3398  PixelChannel
3399  channel;
3400 
3401  PixelTrait
3402  resize_traits,
3403  traits;
3404 
3405  register ssize_t
3406  j;
3407 
3408  ssize_t
3409  k;
3410 
3411  channel=GetPixelChannelChannel(image,i);
3412  traits=GetPixelChannelTraits(image,channel);
3413  resize_traits=GetPixelChannelTraits(resize_image,channel);
3414  if ((traits == UndefinedPixelTrait) ||
3415  (resize_traits == UndefinedPixelTrait))
3416  continue;
3417  if (((resize_traits & CopyPixelTrait) != 0) ||
3418  (GetPixelWriteMask(resize_image,q) <= (QuantumRange/2)))
3419  {
3420  j=(ssize_t) (MagickMin(MagickMax(bisect,(double) start),(double)
3421  stop-1.0)+0.5);
3422  k=y*(contribution[n-1].pixel-contribution[0].pixel+1)+
3423  (contribution[j-start].pixel-contribution[0].pixel);
3424  SetPixelChannel(resize_image,channel,p[k*GetPixelChannels(image)+i],
3425  q);
3426  continue;
3427  }
3428  pixel=0.0;
3429  if ((resize_traits & BlendPixelTrait) == 0)
3430  {
3431  /*
3432  No alpha blending.
3433  */
3434  for (j=0; j < n; j++)
3435  {
3436  k=y*(contribution[n-1].pixel-contribution[0].pixel+1)+
3437  (contribution[j].pixel-contribution[0].pixel);
3438  alpha=contribution[j].weight;
3439  pixel+=alpha*p[k*GetPixelChannels(image)+i];
3440  }
3441  SetPixelChannel(resize_image,channel,ClampToQuantum(pixel),q);
3442  continue;
3443  }
3444  /*
3445  Alpha blending.
3446  */
3447  gamma=0.0;
3448  for (j=0; j < n; j++)
3449  {
3450  k=y*(contribution[n-1].pixel-contribution[0].pixel+1)+
3451  (contribution[j].pixel-contribution[0].pixel);
3452  alpha=contribution[j].weight*QuantumScale*
3453  GetPixelAlpha(image,p+k*GetPixelChannels(image));
3454  pixel+=alpha*p[k*GetPixelChannels(image)+i];
3455  gamma+=alpha;
3456  }
3457  gamma=PerceptibleReciprocal(gamma);
3458  SetPixelChannel(resize_image,channel,ClampToQuantum(gamma*pixel),q);
3459  }
3460  q+=GetPixelChannels(resize_image);
3461  }
3462  if (SyncCacheViewAuthenticPixels(resize_view,exception) == MagickFalse)
3463  status=MagickFalse;
3464  if (image->progress_monitor != (MagickProgressMonitor) NULL)
3465  {
3467  proceed;
3468 
3469 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3470  #pragma omp atomic
3471 #endif
3472  (*progress)++;
3473  proceed=SetImageProgress(image,ResizeImageTag,*progress,span);
3474  if (proceed == MagickFalse)
3475  status=MagickFalse;
3476  }
3477  }
3478  resize_view=DestroyCacheView(resize_view);
3479  image_view=DestroyCacheView(image_view);
3480  contributions=DestroyContributionThreadSet(contributions);
3481  return(status);
3482 }
3483 
3485  const ResizeFilter *magick_restrict resize_filter,
3486  const Image *magick_restrict image,Image *magick_restrict resize_image,
3487  const double y_factor,const MagickSizeType span,
3488  MagickOffsetType *magick_restrict progress,ExceptionInfo *exception)
3489 {
3490  CacheView
3491  *image_view,
3492  *resize_view;
3493 
3494  ClassType
3495  storage_class;
3496 
3498  **magick_restrict contributions;
3499 
3500  double
3501  scale,
3502  support;
3503 
3505  status;
3506 
3507  ssize_t
3508  y;
3509 
3510  /*
3511  Apply filter to resize vertically from image to resize image.
3512  */
3513  scale=MagickMax(1.0/y_factor+MagickEpsilon,1.0);
3514  support=scale*GetResizeFilterSupport(resize_filter);
3515  storage_class=support > 0.5 ? DirectClass : image->storage_class;
3516  if (SetImageStorageClass(resize_image,storage_class,exception) == MagickFalse)
3517  return(MagickFalse);
3518  if (support < 0.5)
3519  {
3520  /*
3521  Support too small even for nearest neighbour: Reduce to point sampling.
3522  */
3523  support=(double) 0.5;
3524  scale=1.0;
3525  }
3526  contributions=AcquireContributionThreadSet((size_t) (2.0*support+3.0));
3527  if (contributions == (ContributionInfo **) NULL)
3528  {
3529  (void) ThrowMagickException(exception,GetMagickModule(),
3530  ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
3531  return(MagickFalse);
3532  }
3533  status=MagickTrue;
3534  scale=PerceptibleReciprocal(scale);
3535  image_view=AcquireVirtualCacheView(image,exception);
3536  resize_view=AcquireAuthenticCacheView(resize_image,exception);
3537 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3538  #pragma omp parallel for schedule(static) shared(progress,status) \
3539  magick_number_threads(image,resize_image,resize_image->rows,1)
3540 #endif
3541  for (y=0; y < (ssize_t) resize_image->rows; y++)
3542  {
3543  const int
3544  id = GetOpenMPThreadId();
3545 
3546  double
3547  bisect,
3548  density;
3549 
3550  register const Quantum
3551  *magick_restrict p;
3552 
3553  register ContributionInfo
3554  *magick_restrict contribution;
3555 
3556  register Quantum
3557  *magick_restrict q;
3558 
3559  register ssize_t
3560  x;
3561 
3562  ssize_t
3563  n,
3564  start,
3565  stop;
3566 
3567  if (status == MagickFalse)
3568  continue;
3569  bisect=(double) (y+0.5)/y_factor+MagickEpsilon;
3570  start=(ssize_t) MagickMax(bisect-support+0.5,0.0);
3571  stop=(ssize_t) MagickMin(bisect+support+0.5,(double) image->rows);
3572  density=0.0;
3573  contribution=contributions[id];
3574  for (n=0; n < (stop-start); n++)
3575  {
3576  contribution[n].pixel=start+n;
3577  contribution[n].weight=GetResizeFilterWeight(resize_filter,scale*
3578  ((double) (start+n)-bisect+0.5));
3579  density+=contribution[n].weight;
3580  }
3581  if (n == 0)
3582  continue;
3583  if ((density != 0.0) && (density != 1.0))
3584  {
3585  register ssize_t
3586  i;
3587 
3588  /*
3589  Normalize.
3590  */
3591  density=PerceptibleReciprocal(density);
3592  for (i=0; i < n; i++)
3593  contribution[i].weight*=density;
3594  }
3595  p=GetCacheViewVirtualPixels(image_view,0,contribution[0].pixel,
3596  image->columns,(size_t) (contribution[n-1].pixel-contribution[0].pixel+1),
3597  exception);
3598  q=QueueCacheViewAuthenticPixels(resize_view,0,y,resize_image->columns,1,
3599  exception);
3600  if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
3601  {
3602  status=MagickFalse;
3603  continue;
3604  }
3605  for (x=0; x < (ssize_t) resize_image->columns; x++)
3606  {
3607  register ssize_t
3608  i;
3609 
3610  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
3611  {
3612  double
3613  alpha,
3614  gamma,
3615  pixel;
3616 
3617  PixelChannel
3618  channel;
3619 
3620  PixelTrait
3621  resize_traits,
3622  traits;
3623 
3624  register ssize_t
3625  j;
3626 
3627  ssize_t
3628  k;
3629 
3630  channel=GetPixelChannelChannel(image,i);
3631  traits=GetPixelChannelTraits(image,channel);
3632  resize_traits=GetPixelChannelTraits(resize_image,channel);
3633  if ((traits == UndefinedPixelTrait) ||
3634  (resize_traits == UndefinedPixelTrait))
3635  continue;
3636  if (((resize_traits & CopyPixelTrait) != 0) ||
3637  (GetPixelWriteMask(resize_image,q) <= (QuantumRange/2)))
3638  {
3639  j=(ssize_t) (MagickMin(MagickMax(bisect,(double) start),(double)
3640  stop-1.0)+0.5);
3641  k=(ssize_t) ((contribution[j-start].pixel-contribution[0].pixel)*
3642  image->columns+x);
3643  SetPixelChannel(resize_image,channel,p[k*GetPixelChannels(image)+i],
3644  q);
3645  continue;
3646  }
3647  pixel=0.0;
3648  if ((resize_traits & BlendPixelTrait) == 0)
3649  {
3650  /*
3651  No alpha blending.
3652  */
3653  for (j=0; j < n; j++)
3654  {
3655  k=(ssize_t) ((contribution[j].pixel-contribution[0].pixel)*
3656  image->columns+x);
3657  alpha=contribution[j].weight;
3658  pixel+=alpha*p[k*GetPixelChannels(image)+i];
3659  }
3660  SetPixelChannel(resize_image,channel,ClampToQuantum(pixel),q);
3661  continue;
3662  }
3663  gamma=0.0;
3664  for (j=0; j < n; j++)
3665  {
3666  k=(ssize_t) ((contribution[j].pixel-contribution[0].pixel)*
3667  image->columns+x);
3668  alpha=contribution[j].weight*QuantumScale*GetPixelAlpha(image,p+k*
3669  GetPixelChannels(image));
3670  pixel+=alpha*p[k*GetPixelChannels(image)+i];
3671  gamma+=alpha;
3672  }
3673  gamma=PerceptibleReciprocal(gamma);
3674  SetPixelChannel(resize_image,channel,ClampToQuantum(gamma*pixel),q);
3675  }
3676  q+=GetPixelChannels(resize_image);
3677  }
3678  if (SyncCacheViewAuthenticPixels(resize_view,exception) == MagickFalse)
3679  status=MagickFalse;
3680  if (image->progress_monitor != (MagickProgressMonitor) NULL)
3681  {
3683  proceed;
3684 
3685 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3686  #pragma omp atomic
3687 #endif
3688  (*progress)++;
3689  proceed=SetImageProgress(image,ResizeImageTag,*progress,span);
3690  if (proceed == MagickFalse)
3691  status=MagickFalse;
3692  }
3693  }
3694  resize_view=DestroyCacheView(resize_view);
3695  image_view=DestroyCacheView(image_view);
3696  contributions=DestroyContributionThreadSet(contributions);
3697  return(status);
3698 }
3699 
3700 MagickExport Image *ResizeImage(const Image *image,const size_t columns,
3701  const size_t rows,const FilterType filter,ExceptionInfo *exception)
3702 {
3703  double
3704  x_factor,
3705  y_factor;
3706 
3707  FilterType
3708  filter_type;
3709 
3710  Image
3711  *filter_image,
3712  *resize_image;
3713 
3715  offset;
3716 
3718  span;
3719 
3721  status;
3722 
3723  ResizeFilter
3724  *resize_filter;
3725 
3726  /*
3727  Acquire resize image.
3728  */
3729  assert(image != (Image *) NULL);
3730  assert(image->signature == MagickCoreSignature);
3731  if (image->debug != MagickFalse)
3732  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
3733  assert(exception != (ExceptionInfo *) NULL);
3734  assert(exception->signature == MagickCoreSignature);
3735  if ((columns == 0) || (rows == 0))
3736  ThrowImageException(ImageError,"NegativeOrZeroImageSize");
3737  if ((columns == image->columns) && (rows == image->rows) &&
3738  (filter == UndefinedFilter))
3739  return(CloneImage(image,0,0,MagickTrue,exception));
3740  /*
3741  Acquire resize filter.
3742  */
3743  x_factor=(double) columns/(double) image->columns;
3744  y_factor=(double) rows/(double) image->rows;
3745  filter_type=LanczosFilter;
3746  if (filter != UndefinedFilter)
3747  filter_type=filter;
3748  else
3749  if ((x_factor == 1.0) && (y_factor == 1.0))
3750  filter_type=PointFilter;
3751  else
3752  if ((image->storage_class == PseudoClass) ||
3753  (image->alpha_trait != UndefinedPixelTrait) ||
3754  ((x_factor*y_factor) > 1.0))
3755  filter_type=MitchellFilter;
3756  resize_filter=AcquireResizeFilter(image,filter_type,MagickFalse,exception);
3757 #if defined(MAGICKCORE_OPENCL_SUPPORT)
3758  resize_image=AccelerateResizeImage(image,columns,rows,resize_filter,
3759  exception);
3760  if (resize_image != (Image *) NULL)
3761  {
3762  resize_filter=DestroyResizeFilter(resize_filter);
3763  return(resize_image);
3764  }
3765 #endif
3766  resize_image=CloneImage(image,columns,rows,MagickTrue,exception);
3767  if (resize_image == (Image *) NULL)
3768  {
3769  resize_filter=DestroyResizeFilter(resize_filter);
3770  return(resize_image);
3771  }
3772  if (x_factor > y_factor)
3773  filter_image=CloneImage(image,columns,image->rows,MagickTrue,exception);
3774  else
3775  filter_image=CloneImage(image,image->columns,rows,MagickTrue,exception);
3776  if (filter_image == (Image *) NULL)
3777  {
3778  resize_filter=DestroyResizeFilter(resize_filter);
3779  return(DestroyImage(resize_image));
3780  }
3781  /*
3782  Resize image.
3783  */
3784  offset=0;
3785  if (x_factor > y_factor)
3786  {
3787  span=(MagickSizeType) (filter_image->columns+rows);
3788  status=HorizontalFilter(resize_filter,image,filter_image,x_factor,span,
3789  &offset,exception);
3790  status&=VerticalFilter(resize_filter,filter_image,resize_image,y_factor,
3791  span,&offset,exception);
3792  }
3793  else
3794  {
3795  span=(MagickSizeType) (filter_image->rows+columns);
3796  status=VerticalFilter(resize_filter,image,filter_image,y_factor,span,
3797  &offset,exception);
3798  status&=HorizontalFilter(resize_filter,filter_image,resize_image,x_factor,
3799  span,&offset,exception);
3800  }
3801  /*
3802  Free resources.
3803  */
3804  filter_image=DestroyImage(filter_image);
3805  resize_filter=DestroyResizeFilter(resize_filter);
3806  if (status == MagickFalse)
3807  {
3808  resize_image=DestroyImage(resize_image);
3809  return((Image *) NULL);
3810  }
3811  resize_image->type=image->type;
3812  return(resize_image);
3813 }
3814 
3815 /*
3816 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3817 % %
3818 % %
3819 % %
3820 % S a m p l e I m a g e %
3821 % %
3822 % %
3823 % %
3824 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3825 %
3826 % SampleImage() scales an image to the desired dimensions with pixel
3827 % sampling. Unlike other scaling methods, this method does not introduce
3828 % any additional color into the scaled image.
3829 %
3830 % The format of the SampleImage method is:
3831 %
3832 % Image *SampleImage(const Image *image,const size_t columns,
3833 % const size_t rows,ExceptionInfo *exception)
3834 %
3835 % A description of each parameter follows:
3836 %
3837 % o image: the image.
3838 %
3839 % o columns: the number of columns in the sampled image.
3840 %
3841 % o rows: the number of rows in the sampled image.
3842 %
3843 % o exception: return any errors or warnings in this structure.
3844 %
3845 */
3846 MagickExport Image *SampleImage(const Image *image,const size_t columns,
3847  const size_t rows,ExceptionInfo *exception)
3848 {
3849 #define SampleImageTag "Sample/Image"
3850 
3851  CacheView
3852  *image_view,
3853  *sample_view;
3854 
3855  Image
3856  *sample_image;
3857 
3859  status;
3860 
3862  progress;
3863 
3864  register ssize_t
3865  x1;
3866 
3867  ssize_t
3868  *x_offset,
3869  y;
3870 
3871  PointInfo
3872  sample_offset;
3873 
3874  /*
3875  Initialize sampled image attributes.
3876  */
3877  assert(image != (const Image *) NULL);
3878  assert(image->signature == MagickCoreSignature);
3879  if (image->debug != MagickFalse)
3880  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
3881  assert(exception != (ExceptionInfo *) NULL);
3882  assert(exception->signature == MagickCoreSignature);
3883  if ((columns == 0) || (rows == 0))
3884  ThrowImageException(ImageError,"NegativeOrZeroImageSize");
3885  if ((columns == image->columns) && (rows == image->rows))
3886  return(CloneImage(image,0,0,MagickTrue,exception));
3887  sample_image=CloneImage(image,columns,rows,MagickTrue,exception);
3888  if (sample_image == (Image *) NULL)
3889  return((Image *) NULL);
3890  /*
3891  Set the sampling offset, default is in the mid-point of sample regions.
3892  */
3893  sample_offset.x=sample_offset.y=0.5-MagickEpsilon;
3894  {
3895  const char
3896  *value;
3897 
3898  value=GetImageArtifact(image,"sample:offset");
3899  if (value != (char *) NULL)
3900  {
3901  GeometryInfo
3902  geometry_info;
3903 
3905  flags;
3906 
3907  (void) ParseGeometry(value,&geometry_info);
3908  flags=ParseGeometry(value,&geometry_info);
3909  sample_offset.x=sample_offset.y=geometry_info.rho/100.0-MagickEpsilon;
3910  if ((flags & SigmaValue) != 0)
3911  sample_offset.y=geometry_info.sigma/100.0-MagickEpsilon;
3912  }
3913  }
3914  /*
3915  Allocate scan line buffer and column offset buffers.
3916  */
3917  x_offset=(ssize_t *) AcquireQuantumMemory((size_t) sample_image->columns,
3918  sizeof(*x_offset));
3919  if (x_offset == (ssize_t *) NULL)
3920  {
3921  sample_image=DestroyImage(sample_image);
3922  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
3923  }
3924  for (x1=0; x1 < (ssize_t) sample_image->columns; x1++)
3925  x_offset[x1]=(ssize_t) ((((double) x1+sample_offset.x)*image->columns)/
3926  sample_image->columns);
3927  /*
3928  Sample each row.
3929  */
3930  status=MagickTrue;
3931  progress=0;
3932  image_view=AcquireVirtualCacheView(image,exception);
3933  sample_view=AcquireAuthenticCacheView(sample_image,exception);
3934 #if defined(MAGICKCORE_OPENMP_SUPPORT)
3935  #pragma omp parallel for schedule(static) shared(status) \
3936  magick_number_threads(image,sample_image,sample_image->rows,1)
3937 #endif
3938  for (y=0; y < (ssize_t) sample_image->rows; y++)
3939  {
3940  register const Quantum
3941  *magick_restrict p;
3942 
3943  register Quantum
3944  *magick_restrict q;
3945 
3946  register ssize_t
3947  x;
3948 
3949  ssize_t
3950  y_offset;
3951 
3952  if (status == MagickFalse)
3953  continue;
3954  y_offset=(ssize_t) ((((double) y+sample_offset.y)*image->rows)/
3955  sample_image->rows);
3956  p=GetCacheViewVirtualPixels(image_view,0,y_offset,image->columns,1,
3957  exception);
3958  q=QueueCacheViewAuthenticPixels(sample_view,0,y,sample_image->columns,1,
3959  exception);
3960  if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
3961  {
3962  status=MagickFalse;
3963  continue;
3964  }
3965  /*
3966  Sample each column.
3967  */
3968  for (x=0; x < (ssize_t) sample_image->columns; x++)
3969  {
3970  register ssize_t
3971  i;
3972 
3973  if (GetPixelWriteMask(sample_image,q) <= (QuantumRange/2))
3974  {
3975  q+=GetPixelChannels(sample_image);
3976  continue;
3977  }
3978  for (i=0; i < (ssize_t) GetPixelChannels(sample_image); i++)
3979  {
3980  PixelChannel
3981  channel;
3982 
3983  PixelTrait
3984  image_traits,
3985  traits;
3986 
3987  channel=GetPixelChannelChannel(sample_image,i);
3988  traits=GetPixelChannelTraits(sample_image,channel);
3989  image_traits=GetPixelChannelTraits(image,channel);
3990  if ((traits == UndefinedPixelTrait) ||
3991  (image_traits == UndefinedPixelTrait))
3992  continue;
3993  SetPixelChannel(sample_image,channel,p[x_offset[x]*GetPixelChannels(
3994  image)+i],q);
3995  }
3996  q+=GetPixelChannels(sample_image);
3997  }
3998  if (SyncCacheViewAuthenticPixels(sample_view,exception) == MagickFalse)
3999  status=MagickFalse;
4000  if (image->progress_monitor != (MagickProgressMonitor) NULL)
4001  {
4003  proceed;
4004 
4005  proceed=SetImageProgress(image,SampleImageTag,progress++,image->rows);
4006  if (proceed == MagickFalse)
4007  status=MagickFalse;
4008  }
4009  }
4010  image_view=DestroyCacheView(image_view);
4011  sample_view=DestroyCacheView(sample_view);
4012  x_offset=(ssize_t *) RelinquishMagickMemory(x_offset);
4013  sample_image->type=image->type;
4014  if (status == MagickFalse)
4015  sample_image=DestroyImage(sample_image);
4016  return(sample_image);
4017 }
4018 
4019 /*
4020 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4021 % %
4022 % %
4023 % %
4024 % S c a l e I m a g e %
4025 % %
4026 % %
4027 % %
4028 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4029 %
4030 % ScaleImage() changes the size of an image to the given dimensions.
4031 %
4032 % The format of the ScaleImage method is:
4033 %
4034 % Image *ScaleImage(const Image *image,const size_t columns,
4035 % const size_t rows,ExceptionInfo *exception)
4036 %
4037 % A description of each parameter follows:
4038 %
4039 % o image: the image.
4040 %
4041 % o columns: the number of columns in the scaled image.
4042 %
4043 % o rows: the number of rows in the scaled image.
4044 %
4045 % o exception: return any errors or warnings in this structure.
4046 %
4047 */
4048 MagickExport Image *ScaleImage(const Image *image,const size_t columns,
4049  const size_t rows,ExceptionInfo *exception)
4050 {
4051 #define ScaleImageTag "Scale/Image"
4052 
4053  CacheView
4054  *image_view,
4055  *scale_view;
4056 
4057  double
4058  alpha,
4059  pixel[CompositePixelChannel],
4060  *scale_scanline,
4061  *scanline,
4062  *x_vector,
4063  *y_vector;
4064 
4065  Image
4066  *scale_image;
4067 
4069  next_column,
4070  next_row,
4071  proceed,
4072  status;
4073 
4074  PixelTrait
4075  scale_traits;
4076 
4077  PointInfo
4078  scale,
4079  span;
4080 
4081  register ssize_t
4082  i;
4083 
4084  ssize_t
4085  n,
4086  number_rows,
4087  y;
4088 
4089  /*
4090  Initialize scaled image attributes.
4091  */
4092  assert(image != (const Image *) NULL);
4093  assert(image->signature == MagickCoreSignature);
4094  if (image->debug != MagickFalse)
4095  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
4096  assert(exception != (ExceptionInfo *) NULL);
4097  assert(exception->signature == MagickCoreSignature);
4098  if ((columns == 0) || (rows == 0))
4099  ThrowImageException(ImageError,"NegativeOrZeroImageSize");
4100  if ((columns == image->columns) && (rows == image->rows))
4101  return(CloneImage(image,0,0,MagickTrue,exception));
4102  scale_image=CloneImage(image,columns,rows,MagickTrue,exception);
4103  if (scale_image == (Image *) NULL)
4104  return((Image *) NULL);
4105  if (SetImageStorageClass(scale_image,DirectClass,exception) == MagickFalse)
4106  {
4107  scale_image=DestroyImage(scale_image);
4108  return((Image *) NULL);
4109  }
4110  /*
4111  Allocate memory.
4112  */
4113  x_vector=(double *) AcquireQuantumMemory((size_t) image->columns,
4114  MaxPixelChannels*sizeof(*x_vector));
4115  scanline=x_vector;
4116  if (image->rows != scale_image->rows)
4117  scanline=(double *) AcquireQuantumMemory((size_t) image->columns,
4118  MaxPixelChannels*sizeof(*scanline));
4119  scale_scanline=(double *) AcquireQuantumMemory((size_t) scale_image->columns,
4120  MaxPixelChannels*sizeof(*scale_scanline));
4121  y_vector=(double *) AcquireQuantumMemory((size_t) image->columns,
4122  MaxPixelChannels*sizeof(*y_vector));
4123  if ((scanline == (double *) NULL) || (scale_scanline == (double *) NULL) ||
4124  (x_vector == (double *) NULL) || (y_vector == (double *) NULL))
4125  {
4126  if ((image->rows != scale_image->rows) && (scanline != (double *) NULL))
4127  scanline=(double *) RelinquishMagickMemory(scanline);
4128  if (scale_scanline != (double *) NULL)
4129  scale_scanline=(double *) RelinquishMagickMemory(scale_scanline);
4130  if (x_vector != (double *) NULL)
4131  x_vector=(double *) RelinquishMagickMemory(x_vector);
4132  if (y_vector != (double *) NULL)
4133  y_vector=(double *) RelinquishMagickMemory(y_vector);
4134  scale_image=DestroyImage(scale_image);
4135  ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
4136  }
4137  /*
4138  Scale image.
4139  */
4140  number_rows=0;
4141  next_row=MagickTrue;
4142  span.y=1.0;
4143  scale.y=(double) scale_image->rows/(double) image->rows;
4144  (void) memset(y_vector,0,(size_t) MaxPixelChannels*image->columns*
4145  sizeof(*y_vector));
4146  n=0;
4147  status=MagickTrue;
4148  image_view=AcquireVirtualCacheView(image,exception);
4149  scale_view=AcquireAuthenticCacheView(scale_image,exception);
4150  for (y=0; y < (ssize_t) scale_image->rows; y++)
4151  {
4152  register const Quantum
4153  *magick_restrict p;
4154 
4155  register Quantum
4156  *magick_restrict q;
4157 
4158  register ssize_t
4159  x;
4160 
4161  if (status == MagickFalse)
4162  break;
4163  q=QueueCacheViewAuthenticPixels(scale_view,0,y,scale_image->columns,1,
4164  exception);
4165  if (q == (Quantum *) NULL)
4166  {
4167  status=MagickFalse;
4168  break;
4169  }
4170  alpha=1.0;
4171  if (scale_image->rows == image->rows)
4172  {
4173  /*
4174  Read a new scanline.
4175  */
4176  p=GetCacheViewVirtualPixels(image_view,0,n++,image->columns,1,
4177  exception);
4178  if (p == (const Quantum *) NULL)
4179  {
4180  status=MagickFalse;
4181  break;
4182  }
4183  for (x=0; x < (ssize_t) image->columns; x++)
4184  {
4185  if (GetPixelWriteMask(image,p) <= (QuantumRange/2))
4186  {
4187  p+=GetPixelChannels(image);
4188  continue;
4189  }
4190  if (image->alpha_trait != UndefinedPixelTrait)
4191  alpha=QuantumScale*GetPixelAlpha(image,p);
4192  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4193  {
4194  PixelChannel channel = GetPixelChannelChannel(image,i);
4195  PixelTrait traits = GetPixelChannelTraits(image,channel);
4196  if ((traits & BlendPixelTrait) == 0)
4197  {
4198  x_vector[x*GetPixelChannels(image)+i]=(double) p[i];
4199  continue;
4200  }
4201  x_vector[x*GetPixelChannels(image)+i]=alpha*p[i];
4202  }
4203  p+=GetPixelChannels(image);
4204  }
4205  }
4206  else
4207  {
4208  /*
4209  Scale Y direction.
4210  */
4211  while (scale.y < span.y)
4212  {
4213  if ((next_row != MagickFalse) &&
4214  (number_rows < (ssize_t) image->rows))
4215  {
4216  /*
4217  Read a new scanline.
4218  */
4219  p=GetCacheViewVirtualPixels(image_view,0,n++,image->columns,1,
4220  exception);
4221  if (p == (const Quantum *) NULL)
4222  {
4223  status=MagickFalse;
4224  break;
4225  }
4226  for (x=0; x < (ssize_t) image->columns; x++)
4227  {
4228  if (GetPixelWriteMask(image,p) <= (QuantumRange/2))
4229  {
4230  p+=GetPixelChannels(image);
4231  continue;
4232  }
4233  if (image->alpha_trait != UndefinedPixelTrait)
4234  alpha=QuantumScale*GetPixelAlpha(image,p);
4235  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4236  {
4237  PixelChannel channel = GetPixelChannelChannel(image,i);
4238  PixelTrait traits = GetPixelChannelTraits(image,channel);
4239  if ((traits & BlendPixelTrait) == 0)
4240  {
4241  x_vector[x*GetPixelChannels(image)+i]=(double) p[i];
4242  continue;
4243  }
4244  x_vector[x*GetPixelChannels(image)+i]=alpha*p[i];
4245  }
4246  p+=GetPixelChannels(image);
4247  }
4248  number_rows++;
4249  }
4250  for (x=0; x < (ssize_t) image->columns; x++)
4251  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4252  y_vector[x*GetPixelChannels(image)+i]+=scale.y*
4253  x_vector[x*GetPixelChannels(image)+i];
4254  span.y-=scale.y;
4255  scale.y=(double) scale_image->rows/(double) image->rows;
4256  next_row=MagickTrue;
4257  }
4258  if ((next_row != MagickFalse) && (number_rows < (ssize_t) image->rows))
4259  {
4260  /*
4261  Read a new scanline.
4262  */
4263  p=GetCacheViewVirtualPixels(image_view,0,n++,image->columns,1,
4264  exception);
4265  if (p == (const Quantum *) NULL)
4266  {
4267  status=MagickFalse;
4268  break;
4269  }
4270  for (x=0; x < (ssize_t) image->columns; x++)
4271  {
4272  if (GetPixelWriteMask(image,p) <= (QuantumRange/2))
4273  {
4274  p+=GetPixelChannels(image);
4275  continue;
4276  }
4277  if (image->alpha_trait != UndefinedPixelTrait)
4278  alpha=QuantumScale*GetPixelAlpha(image,p);
4279  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4280  {
4281  PixelChannel channel = GetPixelChannelChannel(image,i);
4282  PixelTrait traits = GetPixelChannelTraits(image,channel);
4283  if ((traits & BlendPixelTrait) == 0)
4284  {
4285  x_vector[x*GetPixelChannels(image)+i]=(double) p[i];
4286  continue;
4287  }
4288  x_vector[x*GetPixelChannels(image)+i]=alpha*p[i];
4289  }
4290  p+=GetPixelChannels(image);
4291  }
4292  number_rows++;
4293  next_row=MagickFalse;
4294  }
4295  for (x=0; x < (ssize_t) image->columns; x++)
4296  {
4297  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4298  {
4299  pixel[i]=y_vector[x*GetPixelChannels(image)+i]+span.y*
4300  x_vector[x*GetPixelChannels(image)+i];
4301  scanline[x*GetPixelChannels(image)+i]=pixel[i];
4302  y_vector[x*GetPixelChannels(image)+i]=0.0;
4303  }
4304  }
4305  scale.y-=span.y;
4306  if (scale.y <= 0)
4307  {
4308  scale.y=(double) scale_image->rows/(double) image->rows;
4309  next_row=MagickTrue;
4310  }
4311  span.y=1.0;
4312  }
4313  if (scale_image->columns == image->columns)
4314  {
4315  /*
4316  Transfer scanline to scaled image.
4317  */
4318  for (x=0; x < (ssize_t) scale_image->columns; x++)
4319  {
4320  if (GetPixelWriteMask(scale_image,q) <= (QuantumRange/2))
4321  {
4322  q+=GetPixelChannels(scale_image);
4323  continue;
4324  }
4325  if (image->alpha_trait != UndefinedPixelTrait)
4326  {
4327  alpha=QuantumScale*scanline[x*GetPixelChannels(image)+
4329  alpha=PerceptibleReciprocal(alpha);
4330  }
4331  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4332  {
4333  PixelChannel channel = GetPixelChannelChannel(image,i);
4334  PixelTrait traits = GetPixelChannelTraits(image,channel);
4335  scale_traits=GetPixelChannelTraits(scale_image,channel);
4336  if ((traits == UndefinedPixelTrait) ||
4337  (scale_traits == UndefinedPixelTrait))
4338  continue;
4339  if ((traits & BlendPixelTrait) == 0)
4340  {
4341  SetPixelChannel(scale_image,channel,ClampToQuantum(
4342  scanline[x*GetPixelChannels(image)+i]),q);
4343  continue;
4344  }
4345  SetPixelChannel(scale_image,channel,ClampToQuantum(alpha*scanline[
4346  x*GetPixelChannels(image)+i]),q);
4347  }
4348  q+=GetPixelChannels(scale_image);
4349  }
4350  }
4351  else
4352  {
4353  ssize_t
4354  t;
4355 
4356  /*
4357  Scale X direction.
4358  */
4359  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4360  pixel[i]=0.0;
4361  next_column=MagickFalse;
4362  span.x=1.0;
4363  t=0;
4364  for (x=0; x < (ssize_t) image->columns; x++)
4365  {
4366  scale.x=(double) scale_image->columns/(double) image->columns;
4367  while (scale.x >= span.x)
4368  {
4369  if (next_column != MagickFalse)
4370  {
4371  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4372  pixel[i]=0.0;
4373  t++;
4374  }
4375  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4376  {
4377  PixelChannel channel = GetPixelChannelChannel(image,i);
4378  PixelTrait traits = GetPixelChannelTraits(image,channel);
4379  if (traits == UndefinedPixelTrait)
4380  continue;
4381  pixel[i]+=span.x*scanline[x*GetPixelChannels(image)+i];
4382  scale_scanline[t*GetPixelChannels(image)+i]=pixel[i];
4383  }
4384  scale.x-=span.x;
4385  span.x=1.0;
4386  next_column=MagickTrue;
4387  }
4388  if (scale.x > 0)
4389  {
4390  if (next_column != MagickFalse)
4391  {
4392  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4393  pixel[i]=0.0;
4394  next_column=MagickFalse;
4395  t++;
4396  }
4397  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4398  pixel[i]+=scale.x*scanline[x*GetPixelChannels(image)+i];
4399  span.x-=scale.x;
4400  }
4401  }
4402  if (span.x > 0)
4403  {
4404  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4405  pixel[i]+=span.x*scanline[(x-1)*GetPixelChannels(image)+i];
4406  }
4407  if ((next_column == MagickFalse) && (t < (ssize_t) scale_image->columns))
4408  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4409  scale_scanline[t*GetPixelChannels(image)+i]=pixel[i];
4410  /*
4411  Transfer scanline to scaled image.
4412  */
4413  for (x=0; x < (ssize_t) scale_image->columns; x++)
4414  {
4415  if (GetPixelWriteMask(scale_image,q) <= (QuantumRange/2))
4416  {
4417  q+=GetPixelChannels(scale_image);
4418  continue;
4419  }
4420  if (image->alpha_trait != UndefinedPixelTrait)
4421  {
4422  alpha=QuantumScale*scale_scanline[x*GetPixelChannels(image)+
4424  alpha=PerceptibleReciprocal(alpha);
4425  }
4426  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
4427  {
4428  PixelChannel channel = GetPixelChannelChannel(image,i);
4429  PixelTrait traits = GetPixelChannelTraits(image,channel);
4430  scale_traits=GetPixelChannelTraits(scale_image,channel);
4431  if ((traits == UndefinedPixelTrait) ||
4432  (scale_traits == UndefinedPixelTrait))
4433  continue;
4434  if ((traits & BlendPixelTrait) == 0)
4435  {
4436  SetPixelChannel(scale_image,channel,ClampToQuantum(
4437  scale_scanline[x*GetPixelChannels(image)+i]),q);
4438  continue;
4439  }
4440  SetPixelChannel(scale_image,channel,ClampToQuantum(alpha*
4441  scale_scanline[x*GetPixelChannels(image)+i]),q);
4442  }
4443  q+=GetPixelChannels(scale_image);
4444  }
4445  }
4446  if (SyncCacheViewAuthenticPixels(scale_view,exception) == MagickFalse)
4447  {
4448  status=MagickFalse;
4449  break;
4450  }
4452  image->rows);
4453  if (proceed == MagickFalse)
4454  {
4455  status=MagickFalse;
4456  break;
4457  }
4458  }
4459  scale_view=DestroyCacheView(scale_view);
4460  image_view=DestroyCacheView(image_view);
4461  /*
4462  Free allocated memory.
4463  */
4464  y_vector=(double *) RelinquishMagickMemory(y_vector);
4465  scale_scanline=(double *) RelinquishMagickMemory(scale_scanline);
4466  if (scale_image->rows != image->rows)
4467  scanline=(double *) RelinquishMagickMemory(scanline);
4468  x_vector=(double *) RelinquishMagickMemory(x_vector);
4469  scale_image->type=image->type;
4470  if (status == MagickFalse)
4471  scale_image=DestroyImage(scale_image);
4472  return(scale_image);
4473 }
4474 
4475 /*
4476 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4477 % %
4478 % %
4479 % %
4480 % T h u m b n a i l I m a g e %
4481 % %
4482 % %
4483 % %
4484 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
4485 %
4486 % ThumbnailImage() changes the size of an image to the given dimensions and
4487 % removes any associated profiles. The goal is to produce small low cost
4488 % thumbnail images suited for display on the Web.
4489 %
4490 % The format of the ThumbnailImage method is:
4491 %
4492 % Image *ThumbnailImage(const Image *image,const size_t columns,
4493 % const size_t rows,ExceptionInfo *exception)
4494 %
4495 % A description of each parameter follows:
4496 %
4497 % o image: the image.
4498 %
4499 % o columns: the number of columns in the scaled image.
4500 %
4501 % o rows: the number of rows in the scaled image.
4502 %
4503 % o exception: return any errors or warnings in this structure.
4504 %
4505 */
4506 MagickExport Image *ThumbnailImage(const Image *image,const size_t columns,
4507  const size_t rows,ExceptionInfo *exception)
4508 {
4509 #define SampleFactor 5
4510 
4511  char
4512  filename[MagickPathExtent],
4513  value[MagickPathExtent];
4514 
4515  const char
4516  *name;
4517 
4518  Image
4519  *thumbnail_image;
4520 
4521  double
4522  x_factor,
4523  y_factor;
4524 
4525  struct stat
4526  attributes;
4527 
4528  assert(image != (Image *) NULL);
4529  assert(image->signature == MagickCoreSignature);
4530  if (image->debug != MagickFalse)
4531  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
4532  assert(exception != (ExceptionInfo *) NULL);
4533  assert(exception->signature == MagickCoreSignature);
4534  x_factor=(double) columns/(double) image->columns;
4535  y_factor=(double) rows/(double) image->rows;
4536  if ((x_factor*y_factor) > 0.1)
4537  thumbnail_image=ResizeImage(image,columns,rows,image->filter,exception);
4538  else
4539  if (((SampleFactor*columns) < 128) || ((SampleFactor*rows) < 128))
4540  thumbnail_image=ResizeImage(image,columns,rows,image->filter,exception);
4541  else
4542  {
4543  Image
4544  *sample_image;
4545 
4546  sample_image=SampleImage(image,SampleFactor*columns,SampleFactor*rows,
4547  exception);
4548  if (sample_image == (Image *) NULL)
4549  return((Image *) NULL);
4550  thumbnail_image=ResizeImage(sample_image,columns,rows,image->filter,
4551  exception);
4552  sample_image=DestroyImage(sample_image);
4553  }
4554  if (thumbnail_image == (Image *) NULL)
4555  return(thumbnail_image);
4556  (void) ParseAbsoluteGeometry("0x0+0+0",&thumbnail_image->page);
4557  if (thumbnail_image->alpha_trait == UndefinedPixelTrait)
4558  (void) SetImageAlphaChannel(thumbnail_image,OpaqueAlphaChannel,exception);
4559  thumbnail_image->depth=8;
4560  thumbnail_image->interlace=NoInterlace;
4561  /*
4562  Strip all profiles except color profiles.
4563  */
4564  ResetImageProfileIterator(thumbnail_image);
4565  for (name=GetNextImageProfile(thumbnail_image); name != (const char *) NULL; )
4566  {
4567  if ((LocaleCompare(name,"icc") != 0) && (LocaleCompare(name,"icm") != 0))
4568  {
4569  (void) DeleteImageProfile(thumbnail_image,name);
4570  ResetImageProfileIterator(thumbnail_image);
4571  }
4572  name=GetNextImageProfile(thumbnail_image);
4573  }
4574  (void) DeleteImageProperty(thumbnail_image,"comment");
4575  (void) CopyMagickString(value,image->magick_filename,MagickPathExtent);
4576  if (strstr(image->magick_filename,"//") == (char *) NULL)
4577  (void) FormatLocaleString(value,MagickPathExtent,"file://%s",
4578  image->magick_filename);
4579  (void) SetImageProperty(thumbnail_image,"Thumb::URI",value,exception);
4580  GetPathComponent(image->magick_filename,TailPath,filename);
4581  (void) CopyMagickString(value,filename,MagickPathExtent);
4582  if ( GetPathAttributes(image->filename,&attributes) != MagickFalse )
4583  {
4584  (void) FormatLocaleString(value,MagickPathExtent,"%.20g",(double)
4585  attributes.st_mtime);
4586  (void) SetImageProperty(thumbnail_image,"Thumb::MTime",value,exception);
4587  }
4588  (void) FormatLocaleString(value,MagickPathExtent,"%.20g",(double)
4589  attributes.st_mtime);
4591  value);
4592  (void) SetImageProperty(thumbnail_image,"Thumb::Size",value,exception);
4593  (void) FormatLocaleString(value,MagickPathExtent,"image/%s",image->magick);
4594  LocaleLower(value);
4595  (void) SetImageProperty(thumbnail_image,"Thumb::Mimetype",value,exception);
4596  (void) SetImageProperty(thumbnail_image,"software",MagickAuthoritativeURL,
4597  exception);
4598  (void) FormatLocaleString(value,MagickPathExtent,"%.20g",(double)
4599  image->magick_columns);
4600  (void) SetImageProperty(thumbnail_image,"Thumb::Image::Width",value,
4601  exception);
4602  (void) FormatLocaleString(value,MagickPathExtent,"%.20g",(double)
4603  image->magick_rows);
4604  (void) SetImageProperty(thumbnail_image,"Thumb::Image::Height",value,
4605  exception);
4606  (void) FormatLocaleString(value,MagickPathExtent,"%.20g",(double)
4607  GetImageListLength(image));
4608  (void) SetImageProperty(thumbnail_image,"Thumb::Document::Pages",value,
4609  exception);
4610  return(thumbnail_image);
4611 }
size_t rows
Definition: image.h:172
#define magick_restrict
Definition: MagickCore.h:41
MagickExport Image * ResizeImage(const Image *image, const size_t columns, const size_t rows, const FilterType filter, ExceptionInfo *exception)
Definition: resize.c:3700
#define ScaleImageTag
MagickExport CacheView * DestroyCacheView(CacheView *cache_view)
Definition: cache-view.c:252
MagickExport ssize_t FormatMagickSize(const MagickSizeType size, const MagickBooleanType bi, const char *suffix, const size_t length, char *format)
Definition: string.c:1093
#define MagickSQ1_2
Definition: image-private.h:32
static ssize_t GetPixelChannelOffset(const Image *magick_restrict image, const PixelChannel channel)
MagickPrivate double GetResizeFilterWindowSupport(const ResizeFilter *)
static void Eagle3X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2670
double(*)(*) blur
Definition: resize.c:94
MagickExport MemoryInfo * RelinquishVirtualMemory(MemoryInfo *memory_info)
Definition: memory.c:1136
InterlaceType interlace
Definition: image.h:225
MagickExport MagickBooleanType GetPathAttributes(const char *path, void *attributes)
Definition: utility.c:1165
MagickProgressMonitor progress_monitor
Definition: image.h:303
ImageType type
Definition: image.h:264
static MagickBooleanType HorizontalFilter(const ResizeFilter *magick_restrict resize_filter, const Image *magick_restrict image, Image *magick_restrict resize_image, const double x_factor, const MagickSizeType span, MagickOffsetType *magick_restrict progress, ExceptionInfo *exception)
Definition: resize.c:3264
static Quantum GetPixelAlpha(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
FilterType
Definition: resample.h:32
FilterType filter
Definition: image.h:219
double(*)(*) window_support
Definition: resize.c:94
#define MagickAssumeAligned(address)
double(*)(*) coefficient[7]
Definition: resize.c:94
ssize_t y
Definition: geometry.h:116
static double Jinc(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:346
static void Xbr2X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2516
MagickExport ssize_t ParseCommandOption(const CommandOption option, const MagickBooleanType list, const char *options)
Definition: option.c:2972
static double I0(double x)
Definition: resize.c:1341
static void Mix2Pixels(const Quantum *source, const ssize_t source_offset1, const ssize_t source_offset2, Quantum *destination, const ssize_t destination_offset, const size_t channels)
Definition: resize.c:2095
#define WeightVar(M, N)
MagickExport MagickBooleanType DeleteImageProfile(Image *image, const char *name)
Definition: profile.c:220
PixelInterpolateMethod
Definition: pixel.h:110
static double Hann(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:322
MagickExport MemoryInfo * AcquireVirtualMemory(const size_t count, const size_t quantum)
Definition: memory.c:581
static void Epbx2X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2617
size_t signature
Definition: exception.h:123
double rho
Definition: geometry.h:106
MagickExport MagickStatusType ParseAbsoluteGeometry(const char *geometry, RectangleInfo *region_info)
Definition: geometry.c:703
MagickExport MagickBooleanType DeleteImageArtifact(Image *image, const char *artifact)
Definition: artifact.c:198
#define MagickAuthoritativeURL
Definition: version.h:53
#define SampleFactor
static double Blackman(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:149
static double Q1(double x)
Definition: resize.c:1452
#define caseA(N, A, B, C, D)
MagickExport MagickBooleanType InterpolatePixelChannels(const Image *magick_restrict source, const CacheView_ *source_view, const Image *magick_restrict destination, const PixelInterpolateMethod method, const double x, const double y, Quantum *pixel, ExceptionInfo *exception)
Definition: pixel.c:4915
MagickExport const char * GetImageArtifact(const Image *image, const char *artifact)
Definition: artifact.c:273
#define ResizeImageTag
MagickPrivate double GetResizeFilterSupport(const ResizeFilter *)
static ContributionInfo ** AcquireContributionThreadSet(const size_t count)
Definition: resize.c:3237
static void MixPixels(const Quantum *source, const ssize_t *source_offset, const size_t source_size, Quantum *destination, const ssize_t destination_offset, const size_t channels)
Definition: resize.c:2073
static double StringToDouble(const char *magick_restrict string, char **magick_restrict sentinal)
static PixelTrait GetPixelChannelTraits(const Image *magick_restrict image, const PixelChannel channel)
MagickPrivate double GetResizeFilterScale(const ResizeFilter *)
MagickExport Image * LiquidRescaleImage(const Image *image, const size_t magick_unused(columns), const size_t magick_unused(rows), const double magick_unused(delta_x), const double magick_unused(rigidity), ExceptionInfo *exception)
Definition: resize.c:2020
#define MagickPI
Definition: image-private.h:30
MagickPrivate ResizeFilter * AcquireResizeFilter(const Image *, const FilterType, const MagickBooleanType, ExceptionInfo *)
MagickExport Image * SampleImage(const Image *image, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: resize.c:3846
static void Scale2X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2586
ssize_t pixel
Definition: resize.c:3219
MagickExport ssize_t FormatLocaleString(char *magick_restrict string, const size_t length, const char *magick_restrict format,...)
Definition: locale.c:499
ResizeWeightingFunctionType windowWeightingType
Definition: resize.c:101
static void * AcquireCriticalMemory(const size_t size)
#define MagickPI2
Definition: image-private.h:31
char magick[MagickPathExtent]
Definition: image.h:319
size_t magick_rows
Definition: image.h:324
MagickExport const Quantum * GetCacheViewVirtualPixels(const CacheView *cache_view, const ssize_t x, const ssize_t y, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: cache-view.c:651
static long StringToLong(const char *magick_restrict value)
double(*)(*) support
Definition: resize.c:94
MagickExport const char * GetImageOption(const ImageInfo *image_info, const char *option)
Definition: option.c:2303
float MagickFloatType
Definition: magick-type.h:40
#define MagickEpsilon
Definition: magick-type.h:110
double sigma
Definition: geometry.h:106
ClassType storage_class
Definition: image.h:154
static double SincFast(const double, const ResizeFilter *)
size_t width
Definition: geometry.h:130
Definition: log.h:52
ssize_t MagickOffsetType
Definition: magick-type.h:129
MagickExport Image * ThumbnailImage(const Image *image, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: resize.c:4506
Definition: image.h:151
static MagickBooleanType VerticalFilter(const ResizeFilter *magick_restrict resize_filter, const Image *magick_restrict image, Image *magick_restrict resize_image, const double y_factor, const MagickSizeType span, MagickOffsetType *magick_restrict progress, ExceptionInfo *exception)
Definition: resize.c:3484
MagickPrivate double GetResizeFilterBlur(const ResizeFilter *)
double x
Definition: geometry.h:123
#define MagickCoreSignature
static void Scale3X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2738
static void Hq2XHelper(const unsigned int rule, const Quantum *source, Quantum *destination, const ssize_t destination_offset, const size_t channels, const ssize_t e, const ssize_t a, const ssize_t b, const ssize_t d, const ssize_t f, const ssize_t h)
Definition: resize.c:2142
static double Lagrange(const double x, const ResizeFilter *resize_filter)
Definition: resize.c:382
MagickExport void GetPathComponent(const char *path, PathType type, char *component)
Definition: utility.c:1213
MagickExport ssize_t FormatLocaleFile(FILE *file, const char *magick_restrict format,...)
Definition: locale.c:404
MagickExport MagickBooleanType SetImageAlphaChannel(Image *image, const AlphaChannelOption alpha_type, ExceptionInfo *exception)
Definition: channel.c:974
MagickBooleanType
Definition: magick-type.h:158
size_t signature
Definition: resize.c:105
unsigned int MagickStatusType
Definition: magick-type.h:121
static double PerceptibleReciprocal(const double x)
MagickExport void LocaleLower(char *string)
Definition: locale.c:1490
ClassType
Definition: magick-type.h:151
static double BesselOrderOne(double)
Definition: resize.c:1491
MagickExport const char * CommandOptionToMnemonic(const CommandOption option, const ssize_t type)
Definition: option.c:2681
static double Cosine(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:195
struct _ImageInfo * image_info
Definition: image.h:342
#define Magick2PI
Definition: image-private.h:28
static ContributionInfo ** DestroyContributionThreadSet(ContributionInfo **contribution)
Definition: resize.c:3222
static Quantum GetPixelWriteMask(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
MagickExport Image * MinifyImage(const Image *image, ExceptionInfo *exception)
Definition: resize.c:3090
MagickExport void * AcquireQuantumMemory(const size_t count, const size_t quantum)
Definition: memory.c:543
static double P1(double x)
Definition: resize.c:1412
double y
Definition: geometry.h:123
static int GetOpenMPThreadId(void)
MagickExport MagickBooleanType SetImageProperty(Image *image, const char *property, const char *value, ExceptionInfo *exception)
Definition: property.c:4121
#define magick_unused(x)
RectangleInfo page
Definition: image.h:212
size_t magick_columns
Definition: image.h:324
size_t MagickSizeType
Definition: magick-type.h:130
#define MagnifyImageTag
#define MagickPathExtent
static unsigned int Hq2XPatternToNumber(const int *pattern)
Definition: resize.c:2325
MagickExport void * RelinquishAlignedMemory(void *memory)
Definition: memory.c:1032
MagickExport MagickBooleanType IsStringTrue(const char *value)
Definition: string.c:1425
PixelTrait alpha_trait
Definition: image.h:280
MagickExport int GetMagickPrecision(void)
Definition: magick.c:945
MagickExport Quantum * QueueCacheViewAuthenticPixels(CacheView *cache_view, const ssize_t x, const ssize_t y, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: cache-view.c:977
double(* filter)(const double, const ResizeFilter *)
Definition: resize.c:92
MagickPrivate double GetResizeFilterWeight(const ResizeFilter *, const double)
Definition: resize.c:1646
char magick_filename[MagickPathExtent]
Definition: image.h:319
MagickExport MagickBooleanType ThrowMagickException(ExceptionInfo *exception, const char *module, const char *function, const size_t line, const ExceptionType severity, const char *tag, const char *format,...)
Definition: exception.c:1145
static double Triangle(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:543
MagickExport MagickBooleanType LogMagickEvent(const LogEventType type, const char *module, const char *function, const size_t line, const char *format,...)
Definition: log.c:1413
#define Corner(A, B, C, D)
size_t signature
Definition: image.h:354
MagickExport MagickSizeType GetMagickResourceLimit(const ResourceType type)
Definition: resource.c:790
#define QuantumScale
Definition: magick-type.h:115
size_t columns
Definition: image.h:172
struct _ContributionInfo ContributionInfo
ssize_t x
Definition: geometry.h:134
static double Quadratic(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:415
size_t height
Definition: geometry.h:130
MagickExport MagickBooleanType SetImageStorageClass(Image *image, const ClassType storage_class, ExceptionInfo *exception)
Definition: image.c:2615
MagickExport size_t CopyMagickString(char *destination, const char *source, const size_t length)
Definition: string.c:755
MagickExport Image * ResampleImage(const Image *image, const double x_resolution, const double y_resolution, const FilterType filter, ExceptionInfo *exception)
Definition: resize.c:3140
PixelChannel
Definition: pixel.h:67
MagickExport void * AcquireAlignedMemory(const size_t count, const size_t quantum)
Definition: memory.c:242
MagickExport MagickBooleanType CopyImagePixels(Image *image, const Image *source_image, const RectangleInfo *geometry, const OffsetInfo *offset, ExceptionInfo *exception)
Definition: image.c:1049
MagickExport char * GetNextImageProfile(const Image *image)
Definition: profile.c:323
#define MagickMax(x, y)
Definition: image-private.h:26
static void CopyPixels(const Quantum *source, const ssize_t source_offset, Quantum *destination, const ssize_t destination_offset, const size_t channels)
Definition: resize.c:2063
double(*)(*) scale
Definition: resize.c:94
static size_t GetPixelChannels(const Image *magick_restrict image)
MagickExport int LocaleCompare(const char *p, const char *q)
Definition: locale.c:1435
char filename[MagickPathExtent]
Definition: image.h:319
#define GetMagickModule()
Definition: log.h:28
#define ThrowImageException(severity, tag)
static Quantum ClampToQuantum(const MagickRealType value)
Definition: quantum.h:84
static PixelChannel GetPixelChannelChannel(const Image *magick_restrict image, const ssize_t offset)
MagickExport CacheView * AcquireVirtualCacheView(const Image *image, ExceptionInfo *exception)
Definition: cache-view.c:149
#define caseB(N, A, B, C, D, E, F, G, H)
static double Welch(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:558
MagickExport MagickSizeType GetBlobSize(const Image *image)
Definition: blob.c:1803
MagickExport Image * MagnifyImage(const Image *image, ExceptionInfo *exception)
Definition: resize.c:2825
MagickExport Image * AdaptiveResizeImage(const Image *image, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: resize.c:1290
unsigned short Quantum
Definition: magick-type.h:82
MagickExport MagickBooleanType SetImageColorspace(Image *image, const ColorspaceType colorspace, ExceptionInfo *exception)
Definition: colorspace.c:1196
static double Sinc(const double, const ResizeFilter *)
static void Fish2X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2397
static double CubicBC(const double x, const ResizeFilter *resize_filter)
Definition: resize.c:207
MagickExport MagickBooleanType DeleteImageProperty(Image *image, const char *property)
Definition: property.c:279
ResizeWeightingFunctionType
#define InterpolativeResizeImageTag
MagickExport MagickStatusType ParseGeometry(const char *geometry, GeometryInfo *geometry_info)
Definition: geometry.c:853
static void SetPixelChannel(const Image *magick_restrict image, const PixelChannel channel, const Quantum quantum, Quantum *magick_restrict pixel)
static void Eagle2X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2119
static double Hamming(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:334
#define MagickMin(x, y)
Definition: image-private.h:27
ssize_t x
Definition: geometry.h:116
static double Bohman(const double x, const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:164
MagickExport void * RelinquishMagickMemory(void *memory)
Definition: memory.c:1069
#define MaxPixelChannels
Definition: pixel.h:27
PointInfo resolution
Definition: image.h:209
#define magick_unreferenced(x)
#define Line(A, B, C, D)
static int PixelsEqual(const Quantum *source1, ssize_t offset1, const Quantum *source2, ssize_t offset2, const size_t channels)
Definition: resize.c:2105
MagickBooleanType(* MagickProgressMonitor)(const char *, const MagickOffsetType, const MagickSizeType, void *)
Definition: monitor.h:26
ResizeWeightingFunctionType filterWeightingType
Definition: resize.c:101
#define Rotated(p)
#define MagickPrivate
MagickExport void ResetImageProfileIterator(const Image *image)
Definition: profile.c:1364
#define MagickExport
static void Hq2X(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2344
MagickExport Image * ScaleImage(const Image *image, const size_t columns, const size_t rows, ExceptionInfo *exception)
Definition: resize.c:4048
static void Eagle3XB(const Image *source, const Quantum *pixels, Quantum *result, const size_t channels)
Definition: resize.c:2710
MagickExport MagickBooleanType SyncCacheViewAuthenticPixels(CacheView *magick_restrict cache_view, ExceptionInfo *exception)
Definition: cache-view.c:1100
ssize_t y
Definition: geometry.h:134
static double Gaussian(const double x, const ResizeFilter *resize_filter)
Definition: resize.c:287
MagickExport CacheView * AcquireAuthenticCacheView(const Image *image, ExceptionInfo *exception)
Definition: cache-view.c:112
#define SampleImageTag
MagickPrivate double * GetResizeFilterCoefficient(const ResizeFilter *)
MagickExport Image * InterpolativeResizeImage(const Image *image, const size_t columns, const size_t rows, const PixelInterpolateMethod method, ExceptionInfo *exception)
Definition: resize.c:1705
PixelTrait
Definition: pixel.h:134
MagickExport void * GetVirtualMemoryBlob(const MemoryInfo *memory_info)
Definition: memory.c:963
#define HelperCond(a, b, c, d, e, f, g)
MagickPrivate ResizeWeightingFunctionType GetResizeFilterWindowWeightingType(const ResizeFilter *)
Definition: resize.c:1604
MagickExport MagickRealType GetPixelIntensity(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
Definition: pixel.c:2358
MagickExport size_t GetImageListLength(const Image *images)
Definition: list.c:696
MagickPrivate ResizeWeightingFunctionType GetResizeFilterWeightingType(const ResizeFilter *)
MagickPrivate ResizeFilter * DestroyResizeFilter(ResizeFilter *)
Definition: resize.c:1533
static double Kaiser(const double x, const ResizeFilter *resize_filter)
Definition: resize.c:364
double(*)(*) window(const double, const ResizeFilter *)
Definition: resize.c:93
MagickExport Image * DestroyImage(Image *image)
Definition: image.c:1181
MagickExport Image * CloneImage(const Image *image, const size_t columns, const size_t rows, const MagickBooleanType detach, ExceptionInfo *exception)
Definition: image.c:796
static double Box(const double magick_unused(x), const ResizeFilter *magick_unused(resize_filter))
Definition: resize.c:181
#define QuantumRange
Definition: magick-type.h:83
MagickExport MagickBooleanType SetImageProgress(const Image *image, const char *tag, const MagickOffsetType offset, const MagickSizeType extent)
Definition: monitor.c:136
static double J1(double x)
Definition: resize.c:1366
static double CubicSpline(const double x, const ResizeFilter *resize_filter)
Definition: resize.c:247
MagickBooleanType debug
Definition: image.h:334
size_t depth
Definition: image.h:172