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resampling_convolution.hxx |

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2 /* */
3 /* Copyright 1998-2004 by Ullrich Koethe */
4 /* */
5 /* This file is part of the VIGRA computer vision library. */
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7 /* http://hci.iwr.uni-heidelberg.de/vigra/ */
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9 /* ullrich.koethe@iwr.uni-heidelberg.de or */
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35
36 #ifndef VIGRA_RESAMPLING_CONVOLUTION_HXX
37 #define VIGRA_RESAMPLING_CONVOLUTION_HXX
38
39 #include <cmath>
40 #include "stdimage.hxx"
41 #include "array_vector.hxx"
42 #include "rational.hxx"
43 #include "functortraits.hxx"
44 #include "functorexpression.hxx"
45 #include "transformimage.hxx"
46 #include "imagecontainer.hxx"
47 #include "multi_shape.hxx"
48
49 namespace vigra {
50
51 namespace resampling_detail
52 {
53
54 struct MapTargetToSourceCoordinate
55 {
56 MapTargetToSourceCoordinate(Rational<int> const & samplingRatio,
57 Rational<int> const & offset)
58 : a(samplingRatio.denominator()*offset.denominator()),
59 b(samplingRatio.numerator()*offset.numerator()),
60 c(samplingRatio.numerator()*offset.denominator())
61 {}
62
63 // the following functions are more efficient realizations of:
64 // rational_cast<T>(i / samplingRatio + offset);
65 // we need efficiency because this may be called in the inner loop
66
67 int operator()(int i) const
68 {
69 return (i * a + b) / c;
70 }
71
72 double toDouble(int i) const
73 {
74 return double(i * a + b) / c;
75 }
76
77 Rational<int> toRational(int i) const
78 {
79 return Rational<int>(i * a + b, c);
80 }
81
82 bool isExpand2() const
83 {
84 return a == 1 && b == 0 && c == 2;
85 }
86
87 bool isReduce2() const
88 {
89 return a == 2 && b == 0 && c == 1;
90 }
91
92 int a, b, c;
93 };
94
95 } // namespace resampling_detail
96
97 template <>
98 class FunctorTraits<resampling_detail::MapTargetToSourceCoordinate>
99 : public FunctorTraitsBase<resampling_detail::MapTargetToSourceCoordinate>
100 {
101 public:
102 typedef VigraTrueType isUnaryFunctor;
103 };
104
105 template <class SrcIter, class SrcAcc,
106 class DestIter, class DestAcc,
107 class KernelArray>
108 void
109 resamplingExpandLine2(SrcIter s, SrcIter send, SrcAcc src,
110 DestIter d, DestIter dend, DestAcc dest,
111 KernelArray const & kernels)
112 {
113 typedef typename KernelArray::value_type Kernel;
114 typedef typename KernelArray::const_reference KernelRef;
115 typedef typename Kernel::const_iterator KernelIter;
116
117 typedef typename
118 PromoteTraits<typename SrcAcc::value_type, typename Kernel::value_type>::Promote
119 TmpType;
120
121 int wo = send - s;
122 int wn = dend - d;
123 int wo2 = 2*wo - 2;
124
125 int ileft = std::max(kernels[0].right(), kernels[1].right());
126 int iright = wo + std::min(kernels[0].left(), kernels[1].left()) - 1;
127 for(int i = 0; i < wn; ++i, ++d)
128 {
129 int is = i / 2;
130 KernelRef kernel = kernels[i & 1];
131 KernelIter k = kernel.center() + kernel.right();
132 TmpType sum = NumericTraits<TmpType>::zero();
133 if(is < ileft)
134 {
135 for(int m=is-kernel.right(); m <= is-kernel.left(); ++m, --k)
136 {
137 int mm = (m < 0)
138 ? -m
139 : m;
140 sum += *k * src(s, mm);
141 }
142 }
143 else if(is > iright)
144 {
145 for(int m=is-kernel.right(); m <= is-kernel.left(); ++m, --k)
146 {
147 int mm = (m >= wo)
148 ? wo2 - m
149 : m;
150 sum += *k * src(s, mm);
151 }
152 }
153 else
154 {
155 SrcIter ss = s + is - kernel.right();
156 for(int m = 0; m < kernel.size(); ++m, --k, ++ss)
157 {
158 sum += *k * src(ss);
159 }
160 }
161 dest.set(sum, d);
162 }
163 }
164
165 template <class SrcIter, class SrcAcc,
166 class DestIter, class DestAcc,
167 class KernelArray>
168 void
169 resamplingReduceLine2(SrcIter s, SrcIter send, SrcAcc src,
170 DestIter d, DestIter dend, DestAcc dest,
171 KernelArray const & kernels)
172 {
173 typedef typename KernelArray::value_type Kernel;
174 typedef typename KernelArray::const_reference KernelRef;
175 typedef typename Kernel::const_iterator KernelIter;
176
177 KernelRef kernel = kernels[0];
178 KernelIter kbegin = kernel.center() + kernel.right();
179
180 typedef typename
181 PromoteTraits<typename SrcAcc::value_type, typename Kernel::value_type>::Promote
182 TmpType;
183
184 int wo = send - s;
185 int wn = dend - d;
186 int wo2 = 2*wo - 2;
187
188 int ileft = kernel.right();
189 int iright = wo + kernel.left() - 1;
190 for(int i = 0; i < wn; ++i, ++d)
191 {
192 int is = 2 * i;
193 KernelIter k = kbegin;
194 TmpType sum = NumericTraits<TmpType>::zero();
195 if(is < ileft)
196 {
197 for(int m=is-kernel.right(); m <= is-kernel.left(); ++m, --k)
198 {
199 int mm = (m < 0)
200 ? -m
201 : m;
202 sum += *k * src(s, mm);
203 }
204 }
205 else if(is > iright)
206 {
207 for(int m=is-kernel.right(); m <= is-kernel.left(); ++m, --k)
208 {
209 int mm = (m >= wo)
210 ? wo2 - m
211 : m;
212 sum += *k * src(s, mm);
213 }
214 }
215 else
216 {
217 SrcIter ss = s + is - kernel.right();
218 for(int m = 0; m < kernel.size(); ++m, --k, ++ss)
219 {
220 sum += *k * src(ss);
221 }
222 }
223 dest.set(sum, d);
224 }
225 }
226
227 /** \addtogroup ResamplingConvolutionFilters Resampling Convolution Filters
228
229 These functions implement the convolution operation when the source and target images
230 have different sizes. This is realized by accessing a continuous kernel at the
231 appropriate non-integer positions. The technique is, for example, described in
232 D. Schumacher: <i>General Filtered Image Rescaling</i>, in: Graphics Gems III,
233 Academic Press, 1992.
234 */
235 //@{
236
237 /********************************************************/
238 /* */
239 /* resamplingConvolveLine */
240 /* */
241 /********************************************************/
242
243 /** \brief Performs a 1-dimensional resampling convolution of the source signal using the given
244 set of kernels.
245
246 This function is mainly used internally: It is called for each dimension of a
247 higher dimensional array in order to perform a separable resize operation.
248
249 <b> Declaration:</b>
250
251 <b>\#include</b> <vigra/resampling_convolution.hxx><br/>
252 Namespace: vigra
253
254 \code
255 namespace vigra {
256 template <class SrcIter, class SrcAcc,
257 class DestIter, class DestAcc,
258 class KernelArray,
259 class Functor>
260 void
261 resamplingConvolveLine(SrcIter s, SrcIter send, SrcAcc src,
262 DestIter d, DestIter dend, DestAcc dest,
263 KernelArray const & kernels,
264 Functor mapTargetToSourceCoordinate)
265 }
266 \endcode
267
268 */
269 doxygen_overloaded_function(template <...> void resamplingConvolveLine)
270
271 template <class SrcIter, class SrcAcc,
272 class DestIter, class DestAcc,
273 class KernelArray,
274 class Functor>
275 void
276 resamplingConvolveLine(SrcIter s, SrcIter send, SrcAcc src,
277 DestIter d, DestIter dend, DestAcc dest,
278 KernelArray const & kernels,
279 Functor mapTargetToSourceCoordinate)
280 {
281 if(mapTargetToSourceCoordinate.isExpand2())
282 {
283 resamplingExpandLine2(s, send, src, d, dend, dest, kernels);
284 return;
285 }
286 if(mapTargetToSourceCoordinate.isReduce2())
287 {
288 resamplingReduceLine2(s, send, src, d, dend, dest, kernels);
289 return;
290 }
291
292 typedef typename
293 NumericTraits<typename SrcAcc::value_type>::RealPromote
294 TmpType;
295 typedef typename KernelArray::value_type Kernel;
296 typedef typename Kernel::const_iterator KernelIter;
297
298 int wo = send - s;
299 int wn = dend - d;
300 int wo2 = 2*wo - 2;
301
302 int i;
303 typename KernelArray::const_iterator kernel = kernels.begin();
304 for(i=0; i<wn; ++i, ++d, ++kernel)
305 {
306 // use the kernels periodically
307 if(kernel == kernels.end())
308 kernel = kernels.begin();
309
310 // calculate current target point into source location
311 int is = mapTargetToSourceCoordinate(i);
312
313 TmpType sum = NumericTraits<TmpType>::zero();
314
315 int lbound = is - kernel->right(),
316 hbound = is - kernel->left();
317
318 KernelIter k = kernel->center() + kernel->right();
319 if(lbound < 0 || hbound >= wo)
320 {
321 vigra_precondition(-lbound < wo && wo2 - hbound >= 0,
322 "resamplingConvolveLine(): kernel or offset larger than image.");
323 for(int m=lbound; m <= hbound; ++m, --k)
324 {
325 int mm = (m < 0) ?
326 -m :
327 (m >= wo) ?
328 wo2 - m :
329 m;
330 sum = TmpType(sum + *k * src(s, mm));
331 }
332 }
333 else
334 {
335 SrcIter ss = s + lbound;
336 SrcIter ssend = s + hbound;
337
338 for(; ss <= ssend; ++ss, --k)
339 {
340 sum = TmpType(sum + *k * src(ss));
341 }
342 }
343
344 dest.set(sum, d);
345 }
346 }
347
348 template <class Kernel, class MapCoordinate, class KernelArray>
349 void
350 createResamplingKernels(Kernel const & kernel,
351 MapCoordinate const & mapCoordinate, KernelArray & kernels)
352 {
353 for(unsigned int idest = 0; idest < kernels.size(); ++idest)
354 {
355 int isrc = mapCoordinate(idest);
356 double idsrc = mapCoordinate.toDouble(idest);
357 double offset = idsrc - isrc;
358 double radius = kernel.radius();
359 int left = std::min(0, int(ceil(-radius - offset)));
360 int right = std::max(0, int(floor(radius - offset)));
361 kernels[idest].initExplicitly(left, right);
362
363 double x = left + offset;
364 for(int i = left; i <= right; ++i, ++x)
365 kernels[idest][i] = kernel(x);
366 kernels[idest].normalize(1.0, kernel.derivativeOrder(), offset);
367 }
368 }
369
370 /** \brief Apply a resampling filter in the x-direction.
371
372 This function implements a convolution operation in x-direction
373 (i.e. applies a 1D filter to every row) where the width of the source
374 and destination images differ. This is typically used to avoid aliasing if
375 the image is scaled down, or to interpolate smoothly if the image is scaled up.
376 The target coordinates are transformed into source coordinates by
377
378 \code
379 xsource = (xtarget - offset) / samplingRatio
380 \endcode
381
382 The <tt>samplingRatio</tt> and <tt>offset</tt> must be given as \ref vigra::Rational
383 in order to avoid rounding errors in this transformation. It is required that for all
384 pixels of the target image, <tt>xsource</tt> remains within the range of the source
385 image (i.e. <tt>0 <= xsource <= sourceWidth-1</tt>. Since <tt>xsource</tt> is
386 in general not an integer, the <tt>kernel</tt> must be a functor that can be accessed at
387 arbitrary (<tt>double</tt>) coordinates. It must also provide a member function <tt>radius()</tt>
388 which specifies the support (non-zero interval) of the kernel. VIGRA already
389 provides a number of suitable functors, e.g. \ref vigra::Gaussian, \ref vigra::BSpline
390 \ref vigra::CatmullRomSpline, and \ref vigra::CoscotFunction. The function
391 \ref resizeImageSplineInterpolation() is implemented by means of resamplingConvolveX() and
392 resamplingConvolveY().
393
394 <b> Declarations:</b>
395
396 pass 2D array views:
397 \code
398 namespace vigra {
399 template <class T1, class S1,
400 class T2, class S2,
401 class Kernel>
402 void
403 resamplingConvolveX(MultiArrayView<2, T1, S1> const & src,
404 MultiArrayView<2, T2, S2> dest,
405 Kernel const & kernel,
406 Rational<int> const & samplingRatio, Rational<int> const & offset);
407 }
408 \endcode
409
410 \deprecatedAPI{resamplingConvolveX}
411 pass \ref ImageIterators and \ref DataAccessors :
412 \code
413 namespace vigra {
414 template <class SrcIter, class SrcAcc,
415 class DestIter, class DestAcc,
416 class Kernel>
417 void
418 resamplingConvolveX(SrcIter sul, SrcIter slr, SrcAcc src,
419 DestIter dul, DestIter dlr, DestAcc dest,
420 Kernel const & kernel,
421 Rational<int> const & samplingRatio, Rational<int> const & offset);
422 }
423 \endcode
424 use argument objects in conjunction with \ref ArgumentObjectFactories :
425 \code
426 namespace vigra {
427 template <class SrcIter, class SrcAcc,
428 class DestIter, class DestAcc,
429 class Kernel>
430 void
431 resamplingConvolveX(triple<SrcIter, SrcIter, SrcAcc> src,
432 triple<DestIter, DestIter, DestAcc> dest,
433 Kernel const & kernel,
434 Rational<int> const & samplingRatio, Rational<int> const & offset);
435 }
436 \endcode
437 \deprecatedEnd
438
439 <b> Usage:</b>
440
441 <b>\#include</b> <vigra/resampling_convolution.hxx><br/>
442 Namespace: vigra
443
444 \code
445 Rational<int> ratio(2), offset(0);
446
447 MultiArray<2, float> src(w,h),
448 dest(rational_cast<int>(ratio*w), h);
449
450 float sigma = 2.0;
451 Gaussian<float> smooth(sigma);
452 ...
453
454 // simultaneously enlarge and smooth source image
455 resamplingConvolveX(src, dest,
456 smooth, ratio, offset);
457 \endcode
458
459 \deprecatedUsage{resamplingConvolveX}
460 \code
461 Rational<int> ratio(2), offset(0);
462
463 FImage src(w,h),
464 dest(rational_cast<int>(ratio*w), h);
465
466 float sigma = 2.0;
467 Gaussian<float> smooth(sigma);
468 ...
469
470 // simultaneously enlarge and smooth source image
471 resamplingConvolveX(srcImageRange(src), destImageRange(dest),
472 smooth, ratio, offset);
473 \endcode
474 <b> Required Interface:</b>
475 \code
476 Kernel kernel;
477 int kernelRadius = kernel.radius();
478 double x = ...; // must be <= radius()
479 double value = kernel(x);
480 \endcode
481 \deprecatedEnd
482 */
483 doxygen_overloaded_function(template <...> void resamplingConvolveX)
484
485 template <class SrcIter, class SrcAcc,
486 class DestIter, class DestAcc,
487 class Kernel>
488 void
489 resamplingConvolveX(SrcIter sul, SrcIter slr, SrcAcc src,
490 DestIter dul, DestIter dlr, DestAcc dest,
491 Kernel const & kernel,
492 Rational<int> const & samplingRatio, Rational<int> const & offset)
493 {
494 int wold = slr.x - sul.x;
495 int wnew = dlr.x - dul.x;
496
497 vigra_precondition(!samplingRatio.is_inf() && samplingRatio > 0,
498 "resamplingConvolveX(): sampling ratio must be > 0 and < infinity");
499 vigra_precondition(!offset.is_inf(),
500 "resamplingConvolveX(): offset must be < infinity");
501
502 int period = lcm(samplingRatio.numerator(), samplingRatio.denominator());
503 resampling_detail::MapTargetToSourceCoordinate mapCoordinate(samplingRatio, offset);
504
505 ArrayVector<Kernel1D<double> > kernels(period);
506
507 createResamplingKernels(kernel, mapCoordinate, kernels);
508
509 for(; sul.y < slr.y; ++sul.y, ++dul.y)
510 {
511 typename SrcIter::row_iterator sr = sul.rowIterator();
512 typename DestIter::row_iterator dr = dul.rowIterator();
513 resamplingConvolveLine(sr, sr+wold, src, dr, dr+wnew, dest,
514 kernels, mapCoordinate);
515 }
516 }
517
518 template <class SrcIter, class SrcAcc,
519 class DestIter, class DestAcc,
520 class Kernel>
521 inline void
522 resamplingConvolveX(triple<SrcIter, SrcIter, SrcAcc> src,
523 triple<DestIter, DestIter, DestAcc> dest,
524 Kernel const & kernel,
525 Rational<int> const & samplingRatio, Rational<int> const & offset)
526 {
527 resamplingConvolveX(src.first, src.second, src.third,
528 dest.first, dest.second, dest.third,
529 kernel, samplingRatio, offset);
530 }
531
532 template <class T1, class S1,
533 class T2, class S2,
534 class Kernel>
535 inline void
536 resamplingConvolveX(MultiArrayView<2, T1, S1> const & src,
537 MultiArrayView<2, T2, S2> dest,
538 Kernel const & kernel,
539 Rational<int> const & samplingRatio, Rational<int> const & offset)
540 {
541 resamplingConvolveX(srcImageRange(src),
542 destImageRange(dest),
543 kernel, samplingRatio, offset);
544 }
545
546 /********************************************************/
547 /* */
548 /* resamplingConvolveY */
549 /* */
550 /********************************************************/
551
552 /** \brief Apply a resampling filter in the y-direction.
553
554 This function implements a convolution operation in y-direction
555 (i.e. applies a 1D filter to every column) where the height of the source
556 and destination images differ. This is typically used to avoid aliasing if
557 the image is scaled down, or to interpolate smoothly if the image is scaled up.
558 The target coordinates are transformed into source coordinates by
559
560 \code
561 ysource = (ytarget - offset) / samplingRatio
562 \endcode
563
564 The <tt>samplingRatio</tt> and <tt>offset</tt> must be given as \ref vigra::Rational
565 in order to avoid rounding errors in this transformation. It is required that for all
566 pixels of the target image, <tt>ysource</tt> remains within the range of the source
567 image (i.e. <tt>0 <= ysource <= sourceHeight-1</tt>. Since <tt>ysource</tt> is
568 in general not an integer, the <tt>kernel</tt> must be a functor that can be accessed at
569 arbitrary (<tt>double</tt>) coordinates. It must also provide a member function <tt>radius()</tt>
570 which specifies the support (non-zero interval) of the kernel. VIGRA already
571 provides a number of suitable functors, e.g. \ref vigra::Gaussian, \ref vigra::BSpline
572 \ref vigra::CatmullRomSpline, and \ref vigra::CoscotFunction. The function
573 \ref resizeImageSplineInterpolation() is implemented by means of resamplingConvolveX() and
574 resamplingConvolveY().
575
576 <b> Declarations:</b>
577
578 pass 2D array views:
579 \code
580 namespace vigra {
581 template <class T1, class S1,
582 class T2, class S2,
583 class Kernel>
584 void
585 resamplingConvolveY(MultiArrayView<2, T1, S1> const & src,
586 MultiArrayView<2, T2, S2> dest,
587 Kernel const & kernel,
588 Rational<int> const & samplingRatio, Rational<int> const & offset);
589 }
590 \endcode
591
592 \deprecatedAPI{resamplingConvolveY}
593 pass \ref ImageIterators and \ref DataAccessors :
594 \code
595 namespace vigra {
596 template <class SrcIter, class SrcAcc,
597 class DestIter, class DestAcc,
598 class Kernel>
599 void
600 resamplingConvolveY(SrcIter sul, SrcIter slr, SrcAcc src,
601 DestIter dul, DestIter dlr, DestAcc dest,
602 Kernel const & kernel,
603 Rational<int> const & samplingRatio, Rational<int> const & offset);
604 }
605 \endcode
606 use argument objects in conjunction with \ref ArgumentObjectFactories :
607 \code
608 namespace vigra {
609 template <class SrcIter, class SrcAcc,
610 class DestIter, class DestAcc,
611 class Kernel>
612 void
613 resamplingConvolveY(triple<SrcIter, SrcIter, SrcAcc> src,
614 triple<DestIter, DestIter, DestAcc> dest,
615 Kernel const & kernel,
616 Rational<int> const & samplingRatio, Rational<int> const & offset);
617 }
618 \endcode
619 \deprecatedEnd
620
621 <b> Usage:</b>
622
623 <b>\#include</b> <vigra/resampling_convolution.hxx><br/>
624 Namespace: vigra
625
626 \code
627 Rational<int> ratio(2), offset(0);
628
629 MultiArray<2, float> src(w,h),
630 dest(w, rational_cast<int>(ratio*h));
631
632 float sigma = 2.0;
633 Gaussian<float> smooth(sigma);
634 ...
635
636 // simultaneously enlarge and smooth source image
637 resamplingConvolveY(src, dest,
638 smooth, ratio, offset);
639 \endcode
640
641 \deprecatedUsage{resamplingConvolveY}
642 \code
643 Rational<int> ratio(2), offset(0);
644
645 FImage src(w,h),
646 dest(w, rational_cast<int>(ratio*h));
647
648 float sigma = 2.0;
649 Gaussian<float> smooth(sigma);
650 ...
651
652 // simultaneously enlarge and smooth source image
653 resamplingConvolveY(srcImageRange(src), destImageRange(dest),
654 smooth, ratio, offset);
655 \endcode
656 <b> Required Interface:</b>
657 \code
658 Kernel kernel;
659 int kernelRadius = kernel.radius();
660 double y = ...; // must be <= radius()
661 double value = kernel(y);
662 \endcode
663 \deprecatedEnd
664 */
665 doxygen_overloaded_function(template <...> void resamplingConvolveY)
666
667 template <class SrcIter, class SrcAcc,
668 class DestIter, class DestAcc,
669 class Kernel>
670 void
671 resamplingConvolveY(SrcIter sul, SrcIter slr, SrcAcc src,
672 DestIter dul, DestIter dlr, DestAcc dest,
673 Kernel const & kernel,
674 Rational<int> const & samplingRatio, Rational<int> const & offset)
675 {
676 int hold = slr.y - sul.y;
677 int hnew = dlr.y - dul.y;
678
679 vigra_precondition(!samplingRatio.is_inf() && samplingRatio > 0,
680 "resamplingConvolveY(): sampling ratio must be > 0 and < infinity");
681 vigra_precondition(!offset.is_inf(),
682 "resamplingConvolveY(): offset must be < infinity");
683
684 int period = lcm(samplingRatio.numerator(), samplingRatio.denominator());
685
686 resampling_detail::MapTargetToSourceCoordinate mapCoordinate(samplingRatio, offset);
687
688 ArrayVector<Kernel1D<double> > kernels(period);
689
690 createResamplingKernels(kernel, mapCoordinate, kernels);
691
692 for(; sul.x < slr.x; ++sul.x, ++dul.x)
693 {
694 typename SrcIter::column_iterator sc = sul.columnIterator();
695 typename DestIter::column_iterator dc = dul.columnIterator();
696 resamplingConvolveLine(sc, sc+hold, src, dc, dc+hnew, dest,
697 kernels, mapCoordinate);
698 }
699 }
700
701 template <class SrcIter, class SrcAccessor,
702 class DestIter, class DestAccessor,
703 class Kernel>
704 inline void
705 resamplingConvolveY(triple<SrcIter, SrcIter, SrcAccessor> src,
706 triple<DestIter, DestIter, DestAccessor> dest,
707 Kernel const & kernel,
708 Rational<int> const & samplingRatio, Rational<int> const & offset)
709 {
710 resamplingConvolveY(src.first, src.second, src.third,
711 dest.first, dest.second, dest.third,
712 kernel, samplingRatio, offset);
713 }
714
715 template <class T1, class S1,
716 class T2, class S2,
717 class Kernel>
718 inline void
719 resamplingConvolveY(MultiArrayView<2, T1, S1> const & src,
720 MultiArrayView<2, T2, S2> dest,
721 Kernel const & kernel,
722 Rational<int> const & samplingRatio, Rational<int> const & offset)
723 {
724 resamplingConvolveY(srcImageRange(src),
725 destImageRange(dest),
726 kernel, samplingRatio, offset);
727 }
728
729 /********************************************************/
730 /* */
731 /* resamplingConvolveImage */
732 /* */
733 /********************************************************/
734
735 /** \brief Apply two separable resampling filters successively, the first in x-direction,
736 the second in y-direction.
737
738 This function is a shorthand for the concatenation of a call to
739 \ref resamplingConvolveX() and \ref resamplingConvolveY()
740 with the given kernels. See there for detailed documentation.
741
742 <b> Declarations:</b>
743
744 pass 2D array views:
745 \code
746 namespace vigra {
747 template <class T1, class S1,
748 class T2, class S2,
749 class KernelX, class KernelY>
750 void
751 resamplingConvolveImage(MultiArrayView<2, T1, S1> const & src,
752 MultiArrayView<2, T2, S2> dest,
753 KernelX const & kx,
754 Rational<int> const & samplingRatioX, Rational<int> const & offsetX,
755 KernelY const & ky,
756 Rational<int> const & samplingRatioY, Rational<int> const & offsetY);
757 }
758 \endcode
759
760 \deprecatedAPI{resamplingConvolveImage}
761 pass \ref ImageIterators and \ref DataAccessors :
762 \code
763 namespace vigra {
764 template <class SrcIterator, class SrcAccessor,
765 class DestIterator, class DestAccessor,
766 class KernelX, class KernelY>
767 void resamplingConvolveImage(SrcIterator sul,SrcIterator slr, SrcAccessor src,
768 DestIterator dul, DestIterator dlr, DestAccessor dest,
769 KernelX const & kx,
770 Rational<int> const & samplingRatioX, Rational<int> const & offsetX,
771 KernelY const & ky,
772 Rational<int> const & samplingRatioY, Rational<int> const & offsetY);
773 }
774 \endcode
775 use argument objects in conjunction with \ref ArgumentObjectFactories :
776 \code
777 namespace vigra {
778 template <class SrcIterator, class SrcAccessor,
779 class DestIterator, class DestAccessor,
780 class KernelX, class KernelY>
781 void
782 resamplingConvolveImage(triple<SrcIterator, SrcIterator, SrcAccessor> src,
783 triple<DestIterator, DestIterator, DestAccessor> dest,
784 KernelX const & kx,
785 Rational<int> const & samplingRatioX, Rational<int> const & offsetX,
786 KernelY const & ky,
787 Rational<int> const & samplingRatioY, Rational<int> const & offsetY);
788 }
789 \endcode
790 \deprecatedEnd
791
792 <b> Usage:</b>
793
794 <b>\#include</b> <vigra/resampling_convolution.hxx><br/>
795 Namespace: vigra
796
797 \code
798 Rational<int> xratio(2), yratio(3), offset(0);
799
800 MultiArray<2, float> src(w,h),
801 dest(rational_cast<int>(xratio*w), rational_cast<int>(yratio*h));
802
803 float sigma = 2.0;
804 Gaussian<float> smooth(sigma);
805 ...
806
807 // simultaneously enlarge and smooth source image
808 resamplingConvolveImage(src, dest,
809 smooth, xratio, offset,
810 smooth, yratio, offset);
811 \endcode
812 */
813 doxygen_overloaded_function(template <...> void resamplingConvolveImage)
814
815 template <class SrcIterator, class SrcAccessor,
816 class DestIterator, class DestAccessor,
817 class KernelX, class KernelY>
818 void resamplingConvolveImage(SrcIterator sul,SrcIterator slr, SrcAccessor src,
819 DestIterator dul, DestIterator dlr, DestAccessor dest,
820 KernelX const & kx,
821 Rational<int> const & samplingRatioX, Rational<int> const & offsetX,
822 KernelY const & ky,
823 Rational<int> const & samplingRatioY, Rational<int> const & offsetY)
824 {
825 typedef typename
826 NumericTraits<typename SrcAccessor::value_type>::RealPromote
827 TmpType;
828
829 BasicImage<TmpType> tmp(dlr.x - dul.x, slr.y - sul.y);
830
831 resamplingConvolveX(srcIterRange(sul, slr, src),
832 destImageRange(tmp),
833 kx, samplingRatioX, offsetX);
834 resamplingConvolveY(srcImageRange(tmp),
835 destIterRange(dul, dlr, dest),
836 ky, samplingRatioY, offsetY);
837 }
838
839 template <class SrcIterator, class SrcAccessor,
840 class DestIterator, class DestAccessor,
841 class KernelX, class KernelY>
842 inline void
843 resamplingConvolveImage(triple<SrcIterator, SrcIterator, SrcAccessor> src,
844 triple<DestIterator, DestIterator, DestAccessor> dest,
845 KernelX const & kx,
846 Rational<int> const & samplingRatioX, Rational<int> const & offsetX,
847 KernelY const & ky,
848 Rational<int> const & samplingRatioY, Rational<int> const & offsetY)
849 {
850 resamplingConvolveImage(src.first, src.second, src.third,
851 dest.first, dest.second, dest.third,
852 kx, samplingRatioX, offsetX,
853 ky, samplingRatioY, offsetY);
854 }
855
856 template <class T1, class S1,
857 class T2, class S2,
858 class KernelX, class KernelY>
859 inline void
860 resamplingConvolveImage(MultiArrayView<2, T1, S1> const & src,
861 MultiArrayView<2, T2, S2> dest,
862 KernelX const & kx,
863 Rational<int> const & samplingRatioX, Rational<int> const & offsetX,
864 KernelY const & ky,
865 Rational<int> const & samplingRatioY, Rational<int> const & offsetY)
866 {
867 resamplingConvolveImage(srcImageRange(src),
868 destImageRange(dest),
869 kx, samplingRatioX, offsetX,
870 ky, samplingRatioY, offsetY);
871 }
872
873 /** \brief Two-fold down-sampling for image pyramid construction.
874
875 Sorry, no \ref detailedDocumentation() available yet.
876
877 <b> Declarations:</b>
878
879 <b>\#include</b> <vigra/resampling_convolution.hxx><br>
880 Namespace: vigra
881
882 pass 2D array views:
883 \code
884 namespace vigra {
885 template <class SrcIterator, class SrcAccessor,
886 class DestIterator, class DestAccessor>
887 void pyramidReduceBurtFilter(SrcIterator sul, SrcIterator slr, SrcAccessor src,
888 DestIterator dul, DestIterator dlr, DestAccessor dest,
889 double centerValue = 0.4);
890 }
891 \endcode
892
893 \deprecatedAPI{pyramidReduceBurtFilter}
894 pass \ref ImageIterators and \ref DataAccessors :
895 \code
896 namespace vigra {
897 template <class SrcIterator, class SrcAccessor,
898 class DestIterator, class DestAccessor>
899 void pyramidReduceBurtFilter(SrcIterator sul, SrcIterator slr, SrcAccessor src,
900 DestIterator dul, DestIterator dlr, DestAccessor dest,
901 double centerValue = 0.4);
902 }
903 \endcode
904 use argument objects in conjunction with \ref ArgumentObjectFactories :
905 \code
906 namespace vigra {
907 template <class SrcIterator, class SrcAccessor,
908 class DestIterator, class DestAccessor>
909 void pyramidReduceBurtFilter(triple<SrcIterator, SrcIterator, SrcAccessor> src,
910 triple<DestIterator, DestIterator, DestAccessor> dest,
911 double centerValue = 0.4);
912 }
913 \endcode
914 \deprecatedEnd
915
916 use a \ref vigra::ImagePyramid :
917 \code
918 namespace vigra {
919 template <class Image, class Alloc>
920 void pyramidReduceBurtFilter(ImagePyramid<Image, Alloc> & pyramid, int fromLevel, int toLevel,
921 double centerValue = 0.4);
922 }
923 \endcode
924 */
925 doxygen_overloaded_function(template <...> void pyramidReduceBurtFilter)
926
927 template <class SrcIterator, class SrcAccessor,
928 class DestIterator, class DestAccessor>
929 void pyramidReduceBurtFilter(SrcIterator sul, SrcIterator slr, SrcAccessor src,
930 DestIterator dul, DestIterator dlr, DestAccessor dest,
931 double centerValue = 0.4)
932 {
933 vigra_precondition(0.25 <= centerValue && centerValue <= 0.5,
934 "pyramidReduceBurtFilter(): centerValue must be between 0.25 and 0.5.");
935
936 int wold = slr.x - sul.x;
937 int wnew = dlr.x - dul.x;
938 int hold = slr.y - sul.y;
939 int hnew = dlr.y - dul.y;
940
941 vigra_precondition(wnew == (wold + 1) / 2 && hnew == (hold + 1) / 2,
942 "pyramidReduceBurtFilter(): oldSize = ceil(newSize / 2) required.");
943
944 vigra_precondition(wnew == (wold + 1) / 2 && hnew == (hold + 1) / 2,
945 "pyramidReduceBurtFilter(): oldSize = ceil(newSize / 2) required.");
946
947 Rational<int> samplingRatio(1,2), offset(0);
948 resampling_detail::MapTargetToSourceCoordinate mapCoordinate(samplingRatio, offset);
949
950 ArrayVector<Kernel1D<double> > kernels(1);
951 kernels[0].initExplicitly(-2, 2) = 0.25 - centerValue / 2.0, 0.25, centerValue, 0.25, 0.25 - centerValue / 2.0;
952
953 typedef typename
954 NumericTraits<typename SrcAccessor::value_type>::RealPromote
955 TmpType;
956 typedef BasicImage<TmpType> TmpImage;
957 typedef typename TmpImage::traverser TmpIterator;
958
959 BasicImage<TmpType> tmp(wnew, hold);
960
961 TmpIterator tul = tmp.upperLeft();
962
963 for(; sul.y < slr.y; ++sul.y, ++tul.y)
964 {
965 typename SrcIterator::row_iterator sr = sul.rowIterator();
966 typename TmpIterator::row_iterator tr = tul.rowIterator();
967 // FIXME: replace with reduceLineBurtFilter()
968 resamplingConvolveLine(sr, sr+wold, src, tr, tr+wnew, tmp.accessor(),
969 kernels, mapCoordinate);
970 }
971
972 tul = tmp.upperLeft();
973
974 for(; dul.x < dlr.x; ++dul.x, ++tul.x)
975 {
976 typename DestIterator::column_iterator dc = dul.columnIterator();
977 typename TmpIterator::column_iterator tc = tul.columnIterator();
978 resamplingConvolveLine(tc, tc+hold, tmp.accessor(), dc, dc+hnew, dest,
979 kernels, mapCoordinate);
980 }
981 }
982
983 template <class SrcIterator, class SrcAccessor,
984 class DestIterator, class DestAccessor>
985 inline
986 void pyramidReduceBurtFilter(triple<SrcIterator, SrcIterator, SrcAccessor> src,
987 triple<DestIterator, DestIterator, DestAccessor> dest,
988 double centerValue = 0.4)
989 {
990 pyramidReduceBurtFilter(src.first, src.second, src.third,
991 dest.first, dest.second, dest.third, centerValue);
992 }
993
994 template <class Image, class Alloc>
995 inline
996 void pyramidReduceBurtFilter(ImagePyramid<Image, Alloc> & pyramid, int fromLevel, int toLevel,
997 double centerValue = 0.4)
998 {
999 vigra_precondition(fromLevel < toLevel,
1000 "pyramidReduceBurtFilter(): fromLevel must be smaller than toLevel.");
1001 vigra_precondition(pyramid.lowestLevel() <= fromLevel && toLevel <= pyramid.highestLevel(),
1002 "pyramidReduceBurtFilter(): fromLevel and toLevel must be between the lowest and highest pyramid levels (inclusive).");
1003
1004 for(int i=fromLevel+1; i <= toLevel; ++i)
1005 pyramidReduceBurtFilter(srcImageRange(pyramid[i-1]), destImageRange(pyramid[i]), centerValue);
1006 }
1007
1008 /** \brief Two-fold up-sampling for image pyramid reconstruction.
1009
1010 Sorry, no \ref detailedDocumentation() available yet.
1011
1012 <b> Declarations:</b>
1013
1014 <b>\#include</b> <vigra/resampling_convolution.hxx><br>
1015 Namespace: vigra
1016
1017 pass 2D array views:
1018 \code
1019 namespace vigra {
1020 template <class SrcIterator, class SrcAccessor,
1021 class DestIterator, class DestAccessor>
1022 void pyramidExpandBurtFilter(SrcIterator sul, SrcIterator slr, SrcAccessor src,
1023 DestIterator dul, DestIterator dlr, DestAccessor dest,
1024 double centerValue = 0.4);
1025 }
1026 \endcode
1027
1028 \deprecatedAPI{pyramidExpandBurtFilter}
1029 pass \ref ImageIterators and \ref DataAccessors :
1030 \code
1031 namespace vigra {
1032 template <class SrcIterator, class SrcAccessor,
1033 class DestIterator, class DestAccessor>
1034 void pyramidExpandBurtFilter(SrcIterator sul, SrcIterator slr, SrcAccessor src,
1035 DestIterator dul, DestIterator dlr, DestAccessor dest,
1036 double centerValue = 0.4);
1037 }
1038 \endcode
1039 use argument objects in conjunction with \ref ArgumentObjectFactories :
1040 \code
1041 namespace vigra {
1042 template <class SrcIterator, class SrcAccessor,
1043 class DestIterator, class DestAccessor>
1044 void pyramidExpandBurtFilter(triple<SrcIterator, SrcIterator, SrcAccessor> src,
1045 triple<DestIterator, DestIterator, DestAccessor> dest,
1046 double centerValue = 0.4);
1047 }
1048 \endcode
1049 \deprecatedEnd
1050
1051 use a \ref vigra::ImagePyramid :
1052 \code
1053 namespace vigra {
1054 template <class Image, class Alloc>
1055 void pyramidExpandBurtFilter(ImagePyramid<Image, Alloc> & pyramid, int fromLevel, int toLevel,
1056 double centerValue = 0.4);
1057 }
1058 \endcode
1059 */
1060 doxygen_overloaded_function(template <...> void pyramidExpandBurtFilter)
1061
1062 template <class SrcIterator, class SrcAccessor,
1063 class DestIterator, class DestAccessor>
1064 void pyramidExpandBurtFilter(SrcIterator sul, SrcIterator slr, SrcAccessor src,
1065 DestIterator dul, DestIterator dlr, DestAccessor dest,
1066 double centerValue = 0.4)
1067 {
1068 vigra_precondition(0.25 <= centerValue && centerValue <= 0.5,
1069 "pyramidExpandBurtFilter(): centerValue must be between 0.25 and 0.5.");
1070
1071 int wold = slr.x - sul.x;
1072 int wnew = dlr.x - dul.x;
1073 int hold = slr.y - sul.y;
1074 int hnew = dlr.y - dul.y;
1075
1076 vigra_precondition(wold == (wnew + 1) / 2 && hold == (hnew + 1) / 2,
1077 "pyramidExpandBurtFilter(): oldSize = ceil(newSize / 2) required.");
1078
1079 vigra_precondition(wold == (wnew + 1) / 2 && hold == (hnew + 1) / 2,
1080 "pyramidExpandBurtFilter(): oldSize = ceil(newSize / 2) required.");
1081
1082 Rational<int> samplingRatio(2), offset(0);
1083 resampling_detail::MapTargetToSourceCoordinate mapCoordinate(samplingRatio, offset);
1084
1085 ArrayVector<Kernel1D<double> > kernels(2);
1086 kernels[0].initExplicitly(-1, 1) = 0.5 - centerValue, 2.0*centerValue, 0.5 - centerValue;
1087 kernels[1].initExplicitly(-1, 0) = 0.5, 0.5;
1088
1089 typedef typename
1090 NumericTraits<typename SrcAccessor::value_type>::RealPromote
1091 TmpType;
1092 typedef BasicImage<TmpType> TmpImage;
1093 typedef typename TmpImage::traverser TmpIterator;
1094
1095 BasicImage<TmpType> tmp(wnew, hold);
1096
1097 TmpIterator tul = tmp.upperLeft();
1098
1099 for(; sul.y < slr.y; ++sul.y, ++tul.y)
1100 {
1101 typename SrcIterator::row_iterator sr = sul.rowIterator();
1102 typename TmpIterator::row_iterator tr = tul.rowIterator();
1103 // FIXME: replace with expandLineBurtFilter()
1104 resamplingConvolveLine(sr, sr+wold, src, tr, tr+wnew, tmp.accessor(),
1105 kernels, mapCoordinate);
1106 }
1107
1108 tul = tmp.upperLeft();
1109
1110 for(; dul.x < dlr.x; ++dul.x, ++tul.x)
1111 {
1112 typename DestIterator::column_iterator dc = dul.columnIterator();
1113 typename TmpIterator::column_iterator tc = tul.columnIterator();
1114 resamplingConvolveLine(tc, tc+hold, tmp.accessor(), dc, dc+hnew, dest,
1115 kernels, mapCoordinate);
1116 }
1117 }
1118
1119 template <class SrcIterator, class SrcAccessor,
1120 class DestIterator, class DestAccessor>
1121 inline
1122 void pyramidExpandBurtFilter(triple<SrcIterator, SrcIterator, SrcAccessor> src,
1123 triple<DestIterator, DestIterator, DestAccessor> dest,
1124 double centerValue = 0.4)
1125 {
1126 pyramidExpandBurtFilter(src.first, src.second, src.third,
1127 dest.first, dest.second, dest.third, centerValue);
1128 }
1129
1130
1131 template <class Image, class Alloc>
1132 inline
1133 void pyramidExpandBurtFilter(ImagePyramid<Image, Alloc> & pyramid, int fromLevel, int toLevel,
1134 double centerValue = 0.4)
1135 {
1136 vigra_precondition(fromLevel > toLevel,
1137 "pyramidExpandBurtFilter(): fromLevel must be larger than toLevel.");
1138 vigra_precondition(pyramid.lowestLevel() <= toLevel && fromLevel <= pyramid.highestLevel(),
1139 "pyramidExpandBurtFilter(): fromLevel and toLevel must be between the lowest and highest pyramid levels (inclusive).");
1140
1141 for(int i=fromLevel-1; i >= toLevel; --i)
1142 pyramidExpandBurtFilter(srcImageRange(pyramid[i+1]), destImageRange(pyramid[i]), centerValue);
1143 }
1144
1145 /** \brief Create a Laplacian pyramid.
1146
1147 Sorry, no \ref detailedDocumentation() available yet.
1148
1149 <b>\#include</b> <vigra/resampling_convolution.hxx><br>
1150 Namespace: vigra
1151 */
1152 template <class Image, class Alloc>
1153 inline void
1154 pyramidReduceBurtLaplacian(ImagePyramid<Image, Alloc> & pyramid, int fromLevel, int toLevel,
1155 double centerValue = 0.4)
1156 {
1157 using namespace functor;
1158
1159 pyramidReduceBurtFilter(pyramid, fromLevel, toLevel, centerValue);
1160 for(int i=fromLevel; i < toLevel; ++i)
1161 {
1162 typename ImagePyramid<Image, Alloc>::value_type tmpImage(pyramid[i].size());
1163 pyramidExpandBurtFilter(srcImageRange(pyramid[i+1]), destImageRange(tmpImage), centerValue);
1164 combineTwoImages(srcImageRange(tmpImage), srcImage(pyramid[i]), destImage(pyramid[i]),
1165 Arg1() - Arg2());
1166 }
1167 }
1168
1169 /** \brief Reconstruct a Laplacian pyramid.
1170
1171 Sorry, no \ref detailedDocumentation() available yet.
1172
1173 <b>\#include</b> <vigra/resampling_convolution.hxx><br>
1174 Namespace: vigra
1175 */
1176 template <class Image, class Alloc>
1177 inline void
1178 pyramidExpandBurtLaplacian(ImagePyramid<Image, Alloc> & pyramid, int fromLevel, int toLevel,
1179 double centerValue = 0.4)
1180 {
1181 using namespace functor;
1182
1183 vigra_precondition(fromLevel > toLevel,
1184 "pyramidExpandBurtLaplacian(): fromLevel must be larger than toLevel.");
1185 vigra_precondition(pyramid.lowestLevel() <= toLevel && fromLevel <= pyramid.highestLevel(),
1186 "pyramidExpandBurtLaplacian(): fromLevel and toLevel must be between the lowest and highest pyramid levels (inclusive).");
1187
1188 for(int i=fromLevel-1; i >= toLevel; --i)
1189 {
1190 typename ImagePyramid<Image, Alloc>::value_type tmpImage(pyramid[i].size());
1191 pyramidExpandBurtFilter(srcImageRange(pyramid[i+1]), destImageRange(tmpImage), centerValue);
1192 combineTwoImages(srcImageRange(tmpImage), srcImage(pyramid[i]), destImage(pyramid[i]),
1193 Arg1() - Arg2());
1194 }
1195 }
1196
1197 //@}
1198
1199 } // namespace vigra
1200
1201
1202 #endif /* VIGRA_RESAMPLING_CONVOLUTION_HXX */

© Ullrich Köthe (ullrich.koethe@iwr.uni-heidelberg.de) Heidelberg Collaboratory for Image Processing, University of Heidelberg, Germany | html generated using doxygen and Python vigra 1.10.0 (Mon Nov 18 2013)