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| vigra/separableconvolution.hxx |
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    00001 /************************************************************************/
    00002 /*                                                                      */
    00003 /*               Copyright 1998-2002 by Ullrich Koethe                  */
    00004 /*       Cognitive Systems Group, University of Hamburg, Germany        */
    00005 /*                                                                      */
    00006 /*    This file is part of the VIGRA computer vision library.           */
    00007 /*    ( Version 1.4.0, Dec 21 2005 )                                    */
    00008 /*    The VIGRA Website is                                              */
    00009 /*        http://kogs-www.informatik.uni-hamburg.de/~koethe/vigra/      */
    00010 /*    Please direct questions, bug reports, and contributions to        */
    00011 /*        koethe@informatik.uni-hamburg.de          or                  */
    00012 /*        vigra@kogs1.informatik.uni-hamburg.de                         */
    00013 /*                                                                      */
    00014 /*    Permission is hereby granted, free of charge, to any person       */
    00015 /*    obtaining a copy of this software and associated documentation    */
    00016 /*    files (the "Software"), to deal in the Software without           */
    00017 /*    restriction, including without limitation the rights to use,      */
    00018 /*    copy, modify, merge, publish, distribute, sublicense, and/or      */
    00019 /*    sell copies of the Software, and to permit persons to whom the    */
    00020 /*    Software is furnished to do so, subject to the following          */
    00021 /*    conditions:                                                       */
    00022 /*                                                                      */
    00023 /*    The above copyright notice and this permission notice shall be    */
    00024 /*    included in all copies or substantial portions of the             */
    00025 /*    Software.                                                         */
    00026 /*                                                                      */
    00027 /*    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND    */
    00028 /*    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES   */
    00029 /*    OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND          */
    00030 /*    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT       */
    00031 /*    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,      */
    00032 /*    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING      */
    00033 /*    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR     */
    00034 /*    OTHER DEALINGS IN THE SOFTWARE.                                   */
    00035 /*                                                                      */
    00036 /************************************************************************/
    00037
    00038
    00039 #ifndef VIGRA_SEPARABLECONVOLUTION_HXX
    00040 #define VIGRA_SEPARABLECONVOLUTION_HXX
    00041
    00042 #include <cmath>
    00043 #include "vigra/utilities.hxx"
    00044 #include "vigra/numerictraits.hxx"
    00045 #include "vigra/imageiteratoradapter.hxx"
    00046 #include "vigra/bordertreatment.hxx"
    00047 #include "vigra/gaussians.hxx"
    00048 #include "vigra/array_vector.hxx"
    00049
    00050 namespace vigra {
    00051
    00052 /********************************************************/
    00053 /*                                                      */
    00054 /*                internalConvolveLineWrap              */
    00055 /*                                                      */
    00056 /********************************************************/
    00057
    00058 template <class SrcIterator, class SrcAccessor,
    00059           class DestIterator, class DestAccessor,
    00060           class KernelIterator, class KernelAccessor>
    00061 void internalConvolveLineWrap(SrcIterator is, SrcIterator iend, SrcAccessor sa,
    00062                               DestIterator id, DestAccessor da,
    00063                               KernelIterator kernel, KernelAccessor ka,
    00064                               int kleft, int kright)
    00065 {
    00066   //    int w = iend - is;
    00067     int w = std::distance( is, iend );
    00068
    00069     typedef typename NumericTraits<typename
    00070                       SrcAccessor::value_type>::RealPromote SumType;
    00071
    00072     SrcIterator ibegin = is;
    00073
    00074     for(int x=0; x<w; ++x, ++is, ++id)
    00075     {
    00076         KernelIterator ik = kernel + kright;
    00077         SumType sum = NumericTraits<SumType>::zero();
    00078
    00079         if(x < kright)
    00080         {
    00081             int x0 = x - kright;
    00082             SrcIterator iss = iend + x0;
    00083
    00084             for(; x0; ++x0, --ik, ++iss)
    00085             {
    00086                 sum += ka(ik) * sa(iss);
    00087             }
    00088
    00089             iss = ibegin;
    00090             SrcIterator isend = is + (1 - kleft);
    00091             for(; iss != isend ; --ik, ++iss)
    00092             {
    00093                 sum += ka(ik) * sa(iss);
    00094             }
    00095         }
    00096         else if(w-x <= -kleft)
    00097         {
    00098             SrcIterator iss = is + (-kright);
    00099             SrcIterator isend = iend;
    00100             for(; iss != isend ; --ik, ++iss)
    00101             {
    00102                 sum += ka(ik) * sa(iss);
    00103             }
    00104
    00105             int x0 = -kleft - w + x + 1;
    00106             iss = ibegin;
    00107
    00108             for(; x0; --x0, --ik, ++iss)
    00109             {
    00110                 sum += ka(ik) * sa(iss);
    00111             }
    00112         }
    00113         else
    00114         {
    00115             SrcIterator iss = is - kright;
    00116             SrcIterator isend = is + (1 - kleft);
    00117             for(; iss != isend ; --ik, ++iss)
    00118             {
    00119                 sum += ka(ik) * sa(iss);
    00120             }
    00121         }
    00122
    00123         da.set(NumericTraits<typename
    00124                       DestAccessor::value_type>::fromRealPromote(sum), id);
    00125     }
    00126 }
    00127
    00128 /********************************************************/
    00129 /*                                                      */
    00130 /*                internalConvolveLineClip              */
    00131 /*                                                      */
    00132 /********************************************************/
    00133
    00134 template <class SrcIterator, class SrcAccessor,
    00135           class DestIterator, class DestAccessor,
    00136           class KernelIterator, class KernelAccessor,
    00137           class Norm>
    00138 void internalConvolveLineClip(SrcIterator is, SrcIterator iend, SrcAccessor sa,
    00139                               DestIterator id, DestAccessor da,
    00140                               KernelIterator kernel, KernelAccessor ka,
    00141                               int kleft, int kright, Norm norm)
    00142 {
    00143   //    int w = iend - is;
    00144     int w = std::distance( is, iend );
    00145
    00146     typedef typename NumericTraits<typename
    00147                       SrcAccessor::value_type>::RealPromote SumType;
    00148
    00149     SrcIterator ibegin = is;
    00150
    00151     for(int x=0; x<w; ++x, ++is, ++id)
    00152     {
    00153         KernelIterator ik = kernel + kright;
    00154         SumType sum = NumericTraits<SumType>::zero();
    00155
    00156         if(x < kright)
    00157         {
    00158             int x0 = x - kright;
    00159             Norm clipped = NumericTraits<Norm>::zero();
    00160
    00161             for(; x0; ++x0, --ik)
    00162             {
    00163                 clipped += ka(ik);
    00164             }
    00165
    00166             SrcIterator iss = ibegin;
    00167             SrcIterator isend = is + (1 - kleft);
    00168             for(; iss != isend ; --ik, ++iss)
    00169             {
    00170                 sum += ka(ik) * sa(iss);
    00171             }
    00172
    00173             sum = norm / (norm - clipped) * sum;
    00174         }
    00175         else if(w-x <= -kleft)
    00176         {
    00177             SrcIterator iss = is + (-kright);
    00178             SrcIterator isend = iend;
    00179             for(; iss != isend ; --ik, ++iss)
    00180             {
    00181                 sum += ka(ik) * sa(iss);
    00182             }
    00183
    00184             Norm clipped = NumericTraits<Norm>::zero();
    00185
    00186             int x0 = -kleft - w + x + 1;
    00187
    00188             for(; x0; --x0, --ik)
    00189             {
    00190                 clipped += ka(ik);
    00191             }
    00192
    00193             sum = norm / (norm - clipped) * sum;
    00194         }
    00195         else
    00196         {
    00197             SrcIterator iss = is + (-kright);
    00198             SrcIterator isend = is + (1 - kleft);
    00199             for(; iss != isend ; --ik, ++iss)
    00200             {
    00201                 sum += ka(ik) * sa(iss);
    00202             }
    00203         }
    00204
    00205         da.set(NumericTraits<typename
    00206                       DestAccessor::value_type>::fromRealPromote(sum), id);
    00207     }
    00208 }
    00209
    00210 /********************************************************/
    00211 /*                                                      */
    00212 /*             internalConvolveLineReflect              */
    00213 /*                                                      */
    00214 /********************************************************/
    00215
    00216 template <class SrcIterator, class SrcAccessor,
    00217           class DestIterator, class DestAccessor,
    00218           class KernelIterator, class KernelAccessor>
    00219 void internalConvolveLineReflect(SrcIterator is, SrcIterator iend, SrcAccessor sa,
    00220                               DestIterator id, DestAccessor da,
    00221                               KernelIterator kernel, KernelAccessor ka,
    00222                               int kleft, int kright)
    00223 {
    00224   //    int w = iend - is;
    00225     int w = std::distance( is, iend );
    00226
    00227     typedef typename NumericTraits<typename
    00228                       SrcAccessor::value_type>::RealPromote SumType;
    00229
    00230     SrcIterator ibegin = is;
    00231
    00232     for(int x=0; x<w; ++x, ++is, ++id)
    00233     {
    00234         KernelIterator ik = kernel + kright;
    00235         SumType sum = NumericTraits<SumType>::zero();
    00236
    00237         if(x < kright)
    00238         {
    00239             int x0 = x - kright;
    00240             SrcIterator iss = ibegin - x0;
    00241
    00242             for(; x0; ++x0, --ik, --iss)
    00243             {
    00244                 sum += ka(ik) * sa(iss);
    00245             }
    00246
    00247             SrcIterator isend = is + (1 - kleft);
    00248             for(; iss != isend ; --ik, ++iss)
    00249             {
    00250                 sum += ka(ik) * sa(iss);
    00251             }
    00252         }
    00253         else if(w-x <= -kleft)
    00254         {
    00255             SrcIterator iss = is + (-kright);
    00256             SrcIterator isend = iend;
    00257             for(; iss != isend ; --ik, ++iss)
    00258             {
    00259                 sum += ka(ik) * sa(iss);
    00260             }
    00261
    00262             int x0 = -kleft - w + x + 1;
    00263             iss = iend - 2;
    00264
    00265             for(; x0; --x0, --ik, --iss)
    00266             {
    00267                 sum += ka(ik) * sa(iss);
    00268             }
    00269         }
    00270         else
    00271         {
    00272             SrcIterator iss = is + (-kright);
    00273             SrcIterator isend = is + (1 - kleft);
    00274             for(; iss != isend ; --ik, ++iss)
    00275             {
    00276                 sum += ka(ik) * sa(iss);
    00277             }
    00278         }
    00279
    00280         da.set(NumericTraits<typename
    00281                       DestAccessor::value_type>::fromRealPromote(sum), id);
    00282     }
    00283 }
    00284
    00285 /********************************************************/
    00286 /*                                                      */
    00287 /*             internalConvolveLineRepeat               */
    00288 /*                                                      */
    00289 /********************************************************/
    00290
    00291 template <class SrcIterator, class SrcAccessor,
    00292           class DestIterator, class DestAccessor,
    00293           class KernelIterator, class KernelAccessor>
    00294 void internalConvolveLineRepeat(SrcIterator is, SrcIterator iend, SrcAccessor sa,
    00295                               DestIterator id, DestAccessor da,
    00296                               KernelIterator kernel, KernelAccessor ka,
    00297                               int kleft, int kright)
    00298 {
    00299   //    int w = iend - is;
    00300     int w = std::distance( is, iend );
    00301
    00302     typedef typename NumericTraits<typename
    00303                       SrcAccessor::value_type>::RealPromote SumType;
    00304
    00305     SrcIterator ibegin = is;
    00306
    00307     for(int x=0; x<w; ++x, ++is, ++id)
    00308     {
    00309         KernelIterator ik = kernel + kright;
    00310         SumType sum = NumericTraits<SumType>::zero();
    00311
    00312         if(x < kright)
    00313         {
    00314             int x0 = x - kright;
    00315             SrcIterator iss = ibegin;
    00316
    00317             for(; x0; ++x0, --ik)
    00318             {
    00319                 sum += ka(ik) * sa(iss);
    00320             }
    00321
    00322             SrcIterator isend = is + (1 - kleft);
    00323             for(; iss != isend ; --ik, ++iss)
    00324             {
    00325                 sum += ka(ik) * sa(iss);
    00326             }
    00327         }
    00328         else if(w-x <= -kleft)
    00329         {
    00330             SrcIterator iss = is + (-kright);
    00331             SrcIterator isend = iend;
    00332             for(; iss != isend ; --ik, ++iss)
    00333             {
    00334                 sum += ka(ik) * sa(iss);
    00335             }
    00336
    00337             int x0 = -kleft - w + x + 1;
    00338             iss = iend - 1;
    00339
    00340             for(; x0; --x0, --ik)
    00341             {
    00342                 sum += ka(ik) * sa(iss);
    00343             }
    00344         }
    00345         else
    00346         {
    00347             SrcIterator iss = is + (-kright);
    00348             SrcIterator isend = is + (1 - kleft);
    00349             for(; iss != isend ; --ik, ++iss)
    00350             {
    00351                 sum += ka(ik) * sa(iss);
    00352             }
    00353         }
    00354
    00355         da.set(NumericTraits<typename
    00356                       DestAccessor::value_type>::fromRealPromote(sum), id);
    00357     }
    00358 }
    00359
    00360 /********************************************************/
    00361 /*                                                      */
    00362 /*              internalConvolveLineAvoid               */
    00363 /*                                                      */
    00364 /********************************************************/
    00365
    00366 template <class SrcIterator, class SrcAccessor,
    00367           class DestIterator, class DestAccessor,
    00368           class KernelIterator, class KernelAccessor>
    00369 void internalConvolveLineAvoid(SrcIterator is, SrcIterator iend, SrcAccessor sa,
    00370                               DestIterator id, DestAccessor da,
    00371                               KernelIterator kernel, KernelAccessor ka,
    00372                               int kleft, int kright)
    00373 {
    00374   //    int w = iend - is;
    00375     int w = std::distance( is, iend );
    00376
    00377     typedef typename NumericTraits<typename
    00378                       SrcAccessor::value_type>::RealPromote SumType;
    00379
    00380     is += kright;
    00381     id += kright;
    00382
    00383     for(int x=kright; x<w+kleft; ++x, ++is, ++id)
    00384     {
    00385         KernelIterator ik = kernel + kright;
    00386         SumType sum = NumericTraits<SumType>::zero();
    00387
    00388         SrcIterator iss = is + (-kright);
    00389         SrcIterator isend = is + (1 - kleft);
    00390         for(; iss != isend ; --ik, ++iss)
    00391         {
    00392             sum += ka(ik) * sa(iss);
    00393         }
    00394
    00395         da.set(NumericTraits<typename
    00396                       DestAccessor::value_type>::fromRealPromote(sum), id);
    00397     }
    00398 }
    00399
    00400 /********************************************************/
    00401 /*                                                      */
    00402 /*         Separable convolution functions              */
    00403 /*                                                      */
    00404 /********************************************************/
    00405
    00406 /** \addtogroup SeparableConvolution One-dimensional and separable convolution functions
    00407
    00408     Perform 1D convolution and separable filtering in 2 dimensions.
    00409
    00410     These generic convolution functions implement
    00411     the standard convolution operation for a wide range of images and
    00412     signals that fit into the required interface. They need a suitable
    00413     kernel to operate.
    00414 */
    00415 //@{
    00416
    00417 /** \brief Performs a 1 dimensional convolution of the source signal using the given
    00418     kernel.
    00419
    00420     The KernelIterator must point to the center iterator, and
    00421     the kernel's size is given by its left (kleft <= 0) and right
    00422     (kright >= 0) borders. The signal must always be larger than the kernel.
    00423     At those positions where the kernel does not completely fit
    00424     into the signal's range, the specified \ref BorderTreatmentMode is
    00425     applied.
    00426
    00427     The signal's value_type (SrcAccessor::value_type) must be a
    00428     linear space over the kernel's value_type (KernelAccessor::value_type),
    00429     i.e. addition of source values, multiplication with kernel values,
    00430     and NumericTraits must be defined.
    00431     The kernel's value_type must be an algebraic field,
    00432     i.e. the arithmetic operations (+, -, *, /) and NumericTraits must
    00433     be defined.
    00434
    00435     <b> Declarations:</b>
    00436
    00437     pass arguments explicitly:
    00438     \code
    00439     namespace vigra {
    00440         template <class SrcIterator, class SrcAccessor,
    00441                   class DestIterator, class DestAccessor,
    00442                   class KernelIterator, class KernelAccessor>
    00443         void convolveLine(SrcIterator is, SrcIterator isend, SrcAccessor sa,
    00444                           DestIterator id, DestAccessor da,
    00445                           KernelIterator ik, KernelAccessor ka,
    00446                           int kleft, int kright, BorderTreatmentMode border)
    00447     }
    00448     \endcode
    00449
    00450
    00451     use argument objects in conjunction with \ref ArgumentObjectFactories:
    00452     \code
    00453     namespace vigra {
    00454         template <class SrcIterator, class SrcAccessor,
    00455                   class DestIterator, class DestAccessor,
    00456                   class KernelIterator, class KernelAccessor>
    00457         void convolveLine(triple<SrcIterator, SrcIterator, SrcAccessor> src,
    00458                           pair<DestIterator, DestAccessor> dest,
    00459                           tuple5<KernelIterator, KernelAccessor,
    00460                                  int, int, BorderTreatmentMode> kernel)
    00461     }
    00462     \endcode
    00463
    00464     <b> Usage:</b>
    00465
    00466     <b>\#include</b> "<a href="separableconvolution_8hxx-source.html">vigra/separableconvolution.hxx</a>"
    00467
    00468
    00469     \code
    00470     std::vector<float> src, dest;
    00471     ...
    00472
    00473     // define binomial filter of size 5
    00474     static float kernel[] =
    00475            { 1.0/16.0, 4.0/16.0, 6.0/16.0, 4.0/16.0, 1.0/16.0};
    00476
    00477     typedef vigra::StandardAccessor<float> FAccessor;
    00478     typedef vigra::StandardAccessor<float> KernelAccessor;
    00479
    00480
    00481     vigra::convolveLine(src.begin(), src.end(), FAccessor(), dest.begin(), FAccessor(),
    00482              kernel+2, KernelAccessor(), -2, 2, BORDER_TREATMENT_REFLECT);
    00483     //       ^^^^^^^^  this is the center of the kernel
    00484
    00485     \endcode
    00486
    00487     <b> Required Interface:</b>
    00488
    00489     \code
    00490     RandomAccessIterator is, isend;
    00491     RandomAccessIterator id;
    00492     RandomAccessIterator ik;
    00493
    00494     SrcAccessor src_accessor;
    00495     DestAccessor dest_accessor;
    00496     KernelAccessor kernel_accessor;
    00497
    00498     NumericTraits<SrcAccessor::value_type>::RealPromote s = src_accessor(is);
    00499
    00500     s = s + s;
    00501     s = kernel_accessor(ik) * s;
    00502
    00503     dest_accessor.set(
    00504         NumericTraits<DestAccessor::value_type>::fromRealPromote(s), id);
    00505
    00506     \endcode
    00507
    00508     If border == BORDER_TREATMENT_CLIP:
    00509
    00510     \code
    00511     NumericTraits<KernelAccessor::value_type>::RealPromote k = kernel_accessor(ik);
    00512
    00513     k = k + k;
    00514     k = k - k;
    00515     k = k * k;
    00516     k = k / k;
    00517
    00518     \endcode
    00519
    00520     <b> Preconditions:</b>
    00521
    00522     \code
    00523     kleft <= 0
    00524     kright >= 0
    00525     iend - is >= kright + kleft + 1
    00526     \endcode
    00527
    00528     If border == BORDER_TREATMENT_CLIP: Sum of kernel elements must be
    00529     != 0.
    00530
    00531 */
    00532 template <class SrcIterator, class SrcAccessor,
    00533           class DestIterator, class DestAccessor,
    00534           class KernelIterator, class KernelAccessor>
    00535 void convolveLine(SrcIterator is, SrcIterator iend, SrcAccessor sa,
    00536                   DestIterator id, DestAccessor da,
    00537                   KernelIterator ik, KernelAccessor ka,
    00538                   int kleft, int kright, BorderTreatmentMode border)
    00539 {
    00540     typedef typename KernelAccessor::value_type KernelValue;
    00541
    00542     vigra_precondition(kleft <= 0,
    00543                  "convolveLine(): kleft must be <= 0.\n");
    00544     vigra_precondition(kright >= 0,
    00545                  "convolveLine(): kright must be >= 0.\n");
    00546
    00547     //    int w = iend - is;
    00548     int w = std::distance( is, iend );
    00549
    00550     vigra_precondition(w >= kright - kleft + 1,
    00551                  "convolveLine(): kernel longer than line\n");
    00552
    00553     switch(border)
    00554     {
    00555       case BORDER_TREATMENT_WRAP:
    00556       {
    00557         internalConvolveLineWrap(is, iend, sa, id, da, ik, ka, kleft, kright);
    00558         break;
    00559       }
    00560       case BORDER_TREATMENT_AVOID:
    00561       {
    00562         internalConvolveLineAvoid(is, iend, sa, id, da, ik, ka, kleft, kright);
    00563         break;
    00564       }
    00565       case BORDER_TREATMENT_REFLECT:
    00566       {
    00567         internalConvolveLineReflect(is, iend, sa, id, da, ik, ka, kleft, kright);
    00568         break;
    00569       }
    00570       case BORDER_TREATMENT_REPEAT:
    00571       {
    00572         internalConvolveLineRepeat(is, iend, sa, id, da, ik, ka, kleft, kright);
    00573         break;
    00574       }
    00575       case BORDER_TREATMENT_CLIP:
    00576       {
    00577         // find norm of kernel
    00578         typedef typename KernelAccessor::value_type KT;
    00579         KT norm = NumericTraits<KT>::zero();
    00580         KernelIterator iik = ik + kleft;
    00581         for(int i=kleft; i<=kright; ++i, ++iik) norm += ka(iik);
    00582
    00583         vigra_precondition(norm != NumericTraits<KT>::zero(),
    00584                      "convolveLine(): Norm of kernel must be != 0"
    00585                      " in mode BORDER_TREATMENT_CLIP.\n");
    00586
    00587         internalConvolveLineClip(is, iend, sa, id, da, ik, ka, kleft, kright, norm);
    00588         break;
    00589       }
    00590       default:
    00591       {
    00592         vigra_precondition(0,
    00593                      "convolveLine(): Unknown border treatment mode.\n");
    00594       }
    00595     }
    00596 }
    00597
    00598 template <class SrcIterator, class SrcAccessor,
    00599           class DestIterator, class DestAccessor,
    00600           class KernelIterator, class KernelAccessor>
    00601 inline
    00602 void convolveLine(triple<SrcIterator, SrcIterator, SrcAccessor> src,
    00603                   pair<DestIterator, DestAccessor> dest,
    00604                   tuple5<KernelIterator, KernelAccessor,
    00605                          int, int, BorderTreatmentMode> kernel)
    00606 {
    00607     convolveLine(src.first, src.second, src.third,
    00608                  dest.first, dest.second,
    00609                  kernel.first, kernel.second,
    00610                  kernel.third, kernel.fourth, kernel.fifth);
    00611 }
    00612
    00613 /********************************************************/
    00614 /*                                                      */
    00615 /*                      separableConvolveX              */
    00616 /*                                                      */
    00617 /********************************************************/
    00618
    00619 /** \brief Performs a 1 dimensional convolution in x direction.
    00620
    00621     It calls \link SeparableConvolution#convolveLine convolveLine\endlink() for every row of the
    00622     image. See \link SeparableConvolution#convolveLine convolveLine\endlink() for more information about required interfaces
    00623     and vigra_preconditions.
    00624
    00625     <b> Declarations:</b>
    00626
    00627     pass arguments explicitly:
    00628     \code
    00629     namespace vigra {
    00630         template <class SrcImageIterator, class SrcAccessor,
    00631                   class DestImageIterator, class DestAccessor,
    00632                   class KernelIterator, class KernelAccessor>
    00633         void separableConvolveX(SrcImageIterator supperleft,
    00634                                 SrcImageIterator slowerright, SrcAccessor sa,
    00635                                 DestImageIterator dupperleft, DestAccessor da,
    00636                                 KernelIterator ik, KernelAccessor ka,
    00637                                 int kleft, int kright, BorderTreatmentMode border)
    00638     }
    00639     \endcode
    00640
    00641
    00642     use argument objects in conjunction with \ref ArgumentObjectFactories:
    00643     \code
    00644     namespace vigra {
    00645         template <class SrcImageIterator, class SrcAccessor,
    00646                   class DestImageIterator, class DestAccessor,
    00647                   class KernelIterator, class KernelAccessor>
    00648         void separableConvolveX(triple<SrcImageIterator, SrcImageIterator, SrcAccessor> src,
    00649                                 pair<DestImageIterator, DestAccessor> dest,
    00650                                 tuple5<KernelIterator, KernelAccessor,
    00651                                              int, int, BorderTreatmentMode> kernel)
    00652     }
    00653     \endcode
    00654
    00655     <b> Usage:</b>
    00656
    00657     <b>\#include</b> "<a href="separableconvolution_8hxx-source.html">vigra/separableconvolution.hxx</a>"
    00658
    00659
    00660     \code
    00661     vigra::FImage src(w,h), dest(w,h);
    00662     ...
    00663
    00664     // define Gaussian kernel with std. deviation 3.0
    00665     vigra::Kernel1D<double> kernel;
    00666     kernel.initGaussian(3.0);
    00667
    00668     vigra::separableConvolveX(srcImageRange(src), destImage(dest), kernel1d(kernel));
    00669
    00670     \endcode
    00671
    00672 */
    00673 template <class SrcIterator, class SrcAccessor,
    00674           class DestIterator, class DestAccessor,
    00675           class KernelIterator, class KernelAccessor>
    00676 void separableConvolveX(SrcIterator supperleft,
    00677                         SrcIterator slowerright, SrcAccessor sa,
    00678                         DestIterator dupperleft, DestAccessor da,
    00679                         KernelIterator ik, KernelAccessor ka,
    00680                         int kleft, int kright, BorderTreatmentMode border)
    00681 {
    00682     typedef typename KernelAccessor::value_type KernelValue;
    00683
    00684     vigra_precondition(kleft <= 0,
    00685                  "separableConvolveX(): kleft must be <= 0.\n");
    00686     vigra_precondition(kright >= 0,
    00687                  "separableConvolveX(): kright must be >= 0.\n");
    00688
    00689     int w = slowerright.x - supperleft.x;
    00690     int h = slowerright.y - supperleft.y;
    00691
    00692     vigra_precondition(w >= kright - kleft + 1,
    00693                  "separableConvolveX(): kernel longer than line\n");
    00694
    00695     int y;
    00696
    00697     for(y=0; y<h; ++y, ++supperleft.y, ++dupperleft.y)
    00698     {
    00699         typename SrcIterator::row_iterator rs = supperleft.rowIterator();
    00700         typename DestIterator::row_iterator rd = dupperleft.rowIterator();
    00701
    00702         convolveLine(rs, rs+w, sa, rd, da,
    00703                      ik, ka, kleft, kright, border);
    00704     }
    00705 }
    00706
    00707 template <class SrcIterator, class SrcAccessor,
    00708           class DestIterator, class DestAccessor,
    00709           class KernelIterator, class KernelAccessor>
    00710 inline void
    00711 separableConvolveX(triple<SrcIterator, SrcIterator, SrcAccessor> src,
    00712                   pair<DestIterator, DestAccessor> dest,
    00713                   tuple5<KernelIterator, KernelAccessor,
    00714                          int, int, BorderTreatmentMode> kernel)
    00715 {
    00716     separableConvolveX(src.first, src.second, src.third,
    00717                  dest.first, dest.second,
    00718                  kernel.first, kernel.second,
    00719                  kernel.third, kernel.fourth, kernel.fifth);
    00720 }
    00721
    00722
    00723
    00724 /********************************************************/
    00725 /*                                                      */
    00726 /*                      separableConvolveY              */
    00727 /*                                                      */
    00728 /********************************************************/
    00729
    00730 /** \brief Performs a 1 dimensional convolution in y direction.
    00731
    00732     It calls \link SeparableConvolution#convolveLine convolveLine\endlink() for every column of the
    00733     image. See \link SeparableConvolution#convolveLine convolveLine\endlink() for more information about required interfaces
    00734     and vigra_preconditions.
    00735
    00736     <b> Declarations:</b>
    00737
    00738     pass arguments explicitly:
    00739     \code
    00740     namespace vigra {
    00741         template <class SrcImageIterator, class SrcAccessor,
    00742                   class DestImageIterator, class DestAccessor,
    00743                   class KernelIterator, class KernelAccessor>
    00744         void separableConvolveY(SrcImageIterator supperleft,
    00745                                 SrcImageIterator slowerright, SrcAccessor sa,
    00746                                 DestImageIterator dupperleft, DestAccessor da,
    00747                                 KernelIterator ik, KernelAccessor ka,
    00748                                 int kleft, int kright, BorderTreatmentMode border)
    00749     }
    00750     \endcode
    00751
    00752
    00753     use argument objects in conjunction with \ref ArgumentObjectFactories:
    00754     \code
    00755     namespace vigra {
    00756         template <class SrcImageIterator, class SrcAccessor,
    00757                   class DestImageIterator, class DestAccessor,
    00758                   class KernelIterator, class KernelAccessor>
    00759         void separableConvolveY(triple<SrcImageIterator, SrcImageIterator, SrcAccessor> src,
    00760                                 pair<DestImageIterator, DestAccessor> dest,
    00761                                 tuple5<KernelIterator, KernelAccessor,
    00762                                              int, int, BorderTreatmentMode> kernel)
    00763     }
    00764     \endcode
    00765
    00766     <b> Usage:</b>
    00767
    00768     <b>\#include</b> "<a href="separableconvolution_8hxx-source.html">vigra/separableconvolution.hxx</a>"
    00769
    00770
    00771     \code
    00772     vigra::FImage src(w,h), dest(w,h);
    00773     ...
    00774
    00775     // define Gaussian kernel with std. deviation 3.0
    00776     vigra::Kernel1D kernel;
    00777     kernel.initGaussian(3.0);
    00778
    00779     vigra::separableConvolveY(srcImageRange(src), destImage(dest), kernel1d(kernel));
    00780
    00781     \endcode
    00782
    00783 */
    00784 template <class SrcIterator, class SrcAccessor,
    00785           class DestIterator, class DestAccessor,
    00786           class KernelIterator, class KernelAccessor>
    00787 void separableConvolveY(SrcIterator supperleft,
    00788                         SrcIterator slowerright, SrcAccessor sa,
    00789                         DestIterator dupperleft, DestAccessor da,
    00790                         KernelIterator ik, KernelAccessor ka,
    00791                         int kleft, int kright, BorderTreatmentMode border)
    00792 {
    00793     typedef typename KernelAccessor::value_type KernelValue;
    00794
    00795     vigra_precondition(kleft <= 0,
    00796                  "separableConvolveY(): kleft must be <= 0.\n");
    00797     vigra_precondition(kright >= 0,
    00798                  "separableConvolveY(): kright must be >= 0.\n");
    00799
    00800     int w = slowerright.x - supperleft.x;
    00801     int h = slowerright.y - supperleft.y;
    00802
    00803     vigra_precondition(h >= kright - kleft + 1,
    00804                  "separableConvolveY(): kernel longer than line\n");
    00805
    00806     int x;
    00807
    00808     for(x=0; x<w; ++x, ++supperleft.x, ++dupperleft.x)
    00809     {
    00810         typename SrcIterator::column_iterator cs = supperleft.columnIterator();
    00811         typename DestIterator::column_iterator cd = dupperleft.columnIterator();
    00812
    00813         convolveLine(cs, cs+h, sa, cd, da,
    00814                      ik, ka, kleft, kright, border);
    00815     }
    00816 }
    00817
    00818 template <class SrcIterator, class SrcAccessor,
    00819           class DestIterator, class DestAccessor,
    00820           class KernelIterator, class KernelAccessor>
    00821 inline void
    00822 separableConvolveY(triple<SrcIterator, SrcIterator, SrcAccessor> src,
    00823                   pair<DestIterator, DestAccessor> dest,
    00824                   tuple5<KernelIterator, KernelAccessor,
    00825                          int, int, BorderTreatmentMode> kernel)
    00826 {
    00827     separableConvolveY(src.first, src.second, src.third,
    00828                  dest.first, dest.second,
    00829                  kernel.first, kernel.second,
    00830                  kernel.third, kernel.fourth, kernel.fifth);
    00831 }
    00832
    00833 //@}
    00834
    00835 /********************************************************/
    00836 /*                                                      */
    00837 /*                      Kernel1D                        */
    00838 /*                                                      */
    00839 /********************************************************/
    00840
    00841 /** \brief Generic 1 dimensional convolution kernel.
    00842
    00843     This kernel may be used for convolution of 1 dimensional signals or for
    00844     separable convolution of multidimensional signals.
    00845
    00846     Convlution functions access the kernel via a 1 dimensional random access
    00847     iterator which they get by calling \ref center(). This iterator
    00848     points to the center of the kernel. The kernel's size is given by its left() (<=0)
    00849     and right() (>= 0) methods. The desired border treatment mode is
    00850     returned by borderTreatment().
    00851
    00852     The different init functions create a kernel with the specified
    00853     properties. The kernel's value_type must be a linear space, i.e. it
    00854     must define multiplication with doubles and NumericTraits.
    00855
    00856
    00857     The kernel defines a factory function kernel1d() to create an argument object
    00858     (see \ref KernelArgumentObjectFactories).
    00859
    00860     <b> Usage:</b>
    00861
    00862     <b>\#include</b> "<a href="stdconvolution_8hxx-source.html">vigra/stdconvolution.hxx</a>"
    00863
    00864     \code
    00865     vigra::FImage src(w,h), dest(w,h);
    00866     ...
    00867
    00868     // define Gaussian kernel with std. deviation 3.0
    00869     vigra::Kernel1D kernel;
    00870     kernel.initGaussian(3.0);
    00871
    00872     vigra::separableConvolveX(srcImageRange(src), destImage(dest), kernel1d(kernel));
    00873     \endcode
    00874
    00875     <b> Required Interface:</b>
    00876
    00877     \code
    00878     value_type v = vigra::NumericTraits<value_type>::one(); // if norm is not
    00879                                                             // given explicitly
    00880     double d;
    00881
    00882     v = d * v;
    00883     \endcode
    00884 */
    00885
    00886 template <class ARITHTYPE>
    00887 class Kernel1D
    00888 {
    00889   public:
    00890     typedef ArrayVector<ARITHTYPE> InternalVector;
    00891
    00892         /** the kernel's value type
    00893         */
    00894     typedef typename InternalVector::value_type value_type;
    00895
    00896         /** the kernel's reference type
    00897         */
    00898     typedef typename InternalVector::reference reference;
    00899
    00900         /** the kernel's const reference type
    00901         */
    00902     typedef typename InternalVector::const_reference const_reference;
    00903
    00904         /** deprecated -- use Kernel1D::iterator
    00905         */
    00906     typedef typename InternalVector::iterator Iterator;
    00907
    00908         /** 1D random access iterator over the kernel's values
    00909         */
    00910     typedef typename InternalVector::iterator iterator;
    00911
    00912         /** const 1D random access iterator over the kernel's values
    00913         */
    00914     typedef typename InternalVector::const_iterator const_iterator;
    00915
    00916         /** the kernel's accessor
    00917         */
    00918     typedef StandardAccessor<ARITHTYPE> Accessor;
    00919
    00920         /** the kernel's const accessor
    00921         */
    00922     typedef StandardConstAccessor<ARITHTYPE> ConstAccessor;
    00923
    00924     struct InitProxy
    00925     {
    00926         InitProxy(Iterator i, int count, value_type & norm)
    00927         : iter_(i), base_(i),
    00928           count_(count), sum_(count),
    00929           norm_(norm)
    00930         {}
    00931
    00932         ~InitProxy()
    00933         {
    00934             vigra_precondition(count_ == 1 || count_ == sum_,
    00935                   "Kernel1D::initExplicitly(): "
    00936                   "Too few init values.");
    00937         }
    00938
    00939         InitProxy & operator,(value_type const & v)
    00940         {
    00941             if(sum_ == count_) norm_ = *iter_;
    00942
    00943             norm_ += v;
    00944
    00945             --count_;
    00946             vigra_precondition(count_ > 0,
    00947                   "Kernel1D::initExplicitly(): "
    00948                   "Too many init values.");
    00949
    00950             ++iter_;
    00951             *iter_ = v;
    00952
    00953             return *this;
    00954         }
    00955
    00956         Iterator iter_, base_;
    00957         int count_, sum_;
    00958         value_type & norm_;
    00959     };
    00960
    00961     static value_type one() { return NumericTraits<value_type>::one(); }
    00962
    00963         /** Default constructor.
    00964             Creates a kernel of size 1 which would copy the signal
    00965             unchanged.
    00966         */
    00967     Kernel1D()
    00968     : kernel_(),
    00969       left_(0),
    00970       right_(0),
    00971       border_treatment_(BORDER_TREATMENT_CLIP),
    00972       norm_(one())
    00973     {
    00974         kernel_.push_back(norm_);
    00975     }
    00976
    00977         /** Copy constructor.
    00978         */
    00979     Kernel1D(Kernel1D const & k)
    00980     : kernel_(k.kernel_),
    00981       left_(k.left_),
    00982       right_(k.right_),
    00983       border_treatment_(k.border_treatment_),
    00984       norm_(k.norm_)
    00985     {}
    00986
    00987         /** Copy assignment.
    00988         */
    00989     Kernel1D & operator=(Kernel1D const & k)
    00990     {
    00991         if(this != &k)
    00992         {
    00993             left_ = k.left_;
    00994             right_ = k.right_;
    00995             border_treatment_ = k.border_treatment_;
    00996             norm_ = k.norm_;
    00997             kernel_ = k.kernel_;
    00998         }
    00999         return *this;
    01000     }
    01001
    01002         /** Initialization.
    01003             This initializes the kernel with the given constant. The norm becomes
    01004             v*size().
    01005
    01006             Instead of a single value an initializer list of length size()
    01007             can be used like this:
    01008
    01009             \code
    01010             vigra::Kernel1D<float> roberts_gradient_x;
    01011
    01012             roberts_gradient_x.initExplicitly(0, 1) = 1.0, -1.0;
    01013             \endcode
    01014
    01015             In this case, the norm will be set to the sum of the init values.
    01016             An initializer list of wrong length will result in a run-time error.
    01017         */
    01018     InitProxy operator=(value_type const & v)
    01019     {
    01020         int size = right_ - left_ + 1;
    01021         for(unsigned int i=0; i<kernel_.size(); ++i) kernel_[i] = v;
    01022         norm_ = (double)size*v;
    01023
    01024         return InitProxy(kernel_.begin(), size, norm_);
    01025     }
    01026
    01027         /** Destructor.
    01028         */
    01029     ~Kernel1D()
    01030     {}
    01031
    01032         /**
    01033             Init as a sampled Gaussian function. The radius of the kernel is
    01034             always 3*std_dev. '<tt>norm</tt>' denotes the sum of all bins of the kernel
    01035             (i.e. the kernel is corrected for the normalization error introduced
    01036              by windowing the Gaussian to a finite interval). However,
    01037             if <tt>norm</tt> is 0.0, the kernel is normalized to 1 by the analytic
    01038             expression for the Gaussian, and <b>no</b> correction for the windowing
    01039             error is performed.
    01040
    01041             Precondition:
    01042             \code
    01043             std_dev >= 0.0
    01044             \endcode
    01045
    01046             Postconditions:
    01047             \code
    01048             1. left()  == -(int)(3.0*std_dev + 0.5)
    01049             2. right() ==  (int)(3.0*std_dev + 0.5)
    01050             3. borderTreatment() == BORDER_TREATMENT_CLIP
    01051             4. norm() == norm
    01052             \endcode
    01053         */
    01054     void initGaussian(double std_dev, value_type norm);
    01055
    01056         /** Init as a Gaussian function with norm 1.
    01057          */
    01058     void initGaussian(double std_dev)
    01059     {
    01060         initGaussian(std_dev, one());
    01061     }
    01062
    01063
    01064         /**
    01065             Init as Lindeberg's discrete analog of the Gaussian function. The radius of the kernel is
    01066             always 3*std_dev. 'norm' denotes the sum of all bins of the kernel.
    01067
    01068             Precondition:
    01069             \code
    01070             std_dev >= 0.0
    01071             \endcode
    01072
    01073             Postconditions:
    01074             \code
    01075             1. left()  == -(int)(3.0*std_dev + 0.5)
    01076             2. right() ==  (int)(3.0*std_dev + 0.5)
    01077             3. borderTreatment() == BORDER_TREATMENT_REFLECT
    01078             4. norm() == norm
    01079             \endcode
    01080         */
    01081     void initDiscreteGaussian(double std_dev, value_type norm);
    01082
    01083         /** Init as a LOineberg's discrete analog of the Gaussian function
    01084             with norm 1.
    01085          */
    01086     void initDiscreteGaussian(double std_dev)
    01087     {
    01088         initDiscreteGaussian(std_dev, one());
    01089     }
    01090
    01091         /**
    01092             Init as a Gaussian derivative of order '<tt>order</tt>'.
    01093             The radius of the kernel is always <tt>3*std_dev + 0.5*order</tt>.
    01094             '<tt>norm</tt>' denotes the norm of the kernel so that the
    01095             following condition is fulfilled:
    01096
    01097             \f[ \sum_{i=left()}^{right()}
    01098                          \frac{(-i)^{order}kernel[i]}{order!} = norm
    01099             \f]
    01100
    01101             Thus, the kernel will be corrected for the error introduced
    01102             by windowing the Gaussian to a finite interval. However,
    01103             if <tt>norm</tt> is 0.0, the kernel is normalized to 1 by the analytic
    01104             expression for the Gaussian derivative, and <b>no</b> correction for the
    01105             windowing error is performed.
    01106
    01107             Preconditions:
    01108             \code
    01109             1. std_dev >= 0.0
    01110             2. order   >= 1
    01111             \endcode
    01112
    01113             Postconditions:
    01114             \code
    01115             1. left()  == -(int)(3.0*std_dev + 0.5*order + 0.5)
    01116             2. right() ==  (int)(3.0*std_dev + 0.5*order + 0.5)
    01117             3. borderTreatment() == BORDER_TREATMENT_REPEAT
    01118             4. norm() == norm
    01119             \endcode
    01120         */
    01121     void initGaussianDerivative(double std_dev, int order, value_type norm);
    01122
    01123         /** Init as a Gaussian derivative with norm 1.
    01124          */
    01125     void initGaussianDerivative(double std_dev, int order)
    01126     {
    01127         initGaussianDerivative(std_dev, order, one());
    01128     }
    01129
    01130         /**
    01131             Init as a Binomial filter. 'norm' denotes the sum of all bins
    01132             of the kernel.
    01133
    01134             Precondition:
    01135             \code
    01136             radius   >= 0
    01137             \endcode
    01138
    01139             Postconditions:
    01140             \code
    01141             1. left()  == -radius
    01142             2. right() ==  radius
    01143             3. borderTreatment() == BORDER_TREATMENT_REFLECT
    01144             4. norm() == norm
    01145             \endcode
    01146         */
    01147     void initBinomial(int radius, value_type norm);
    01148
    01149         /** Init as a Binomial filter with norm 1.
    01150          */
    01151     void initBinomial(int radius)
    01152     {
    01153         initBinomial(radius, one());
    01154     }
    01155
    01156         /**
    01157             Init as an Averaging filter. 'norm' denotes the sum of all bins
    01158             of the kernel. The window size is (2*radius+1) * (2*radius+1)
    01159
    01160             Precondition:
    01161             \code
    01162             radius   >= 0
    01163             \endcode
    01164
    01165             Postconditions:
    01166             \code
    01167             1. left()  == -radius
    01168             2. right() ==  radius
    01169             3. borderTreatment() == BORDER_TREATMENT_CLIP
    01170             4. norm() == norm
    01171             \endcode
    01172         */
    01173     void initAveraging(int radius, value_type norm);
    01174
    01175         /** Init as a Averaging filter with norm 1.
    01176          */
    01177     void initAveraging(int radius)
    01178     {
    01179         initAveraging(radius, one());
    01180     }
    01181
    01182         /**
    01183             Init as a symmetric gradient filter of the form
    01184            <TT>[ 0.5 * norm, 0.0 * norm, -0.5 * norm]</TT>
    01185
    01186             Postconditions:
    01187             \code
    01188             1. left()  == -1
    01189             2. right() ==  1
    01190             3. borderTreatment() == BORDER_TREATMENT_REPEAT
    01191             4. norm() == norm
    01192             \endcode
    01193         */
    01194     void
    01195     initSymmetricGradient(value_type norm );
    01196
    01197         /** Init as a symmetric gradient filter with norm 1.
    01198          */
    01199     void initSymmetricGradient()
    01200     {
    01201         initSymmetricGradient(one());
    01202     }
    01203
    01204         /** Init the kernel by an explicit initializer list.
    01205             The left and right boundaries of the kernel must be passed.
    01206             A comma-separated initializer list is given after the assignment
    01207             operator. This function is used like this:
    01208
    01209             \code
    01210             // define horizontal Roberts filter
    01211             vigra::Kernel1D<float> roberts_gradient_x;
    01212
    01213             roberts_gradient_x.initExplicitly(0, 1) = 1.0, -1.0;
    01214             \endcode
    01215
    01216             The norm is set to the sum of the initialzer values. If the wrong number of
    01217             values is given, a run-time error results. It is, however, possible to give
    01218             just one initializer. This creates an averaging filter with the given constant:
    01219
    01220             \code
    01221             vigra::Kernel1D<float> average5x1;
    01222
    01223             average5x1.initExplicitly(-2, 2) = 1.0/5.0;
    01224             \endcode
    01225
    01226             Here, the norm is set to value*size().
    01227
    01228             <b> Preconditions:</b>
    01229
    01230             \code
    01231
    01232             1. left <= 0
    01233             2. right >= 0
    01234             3. the number of values in the initializer list
    01235                is 1 or equals the size of the kernel.
    01236             \endcode
    01237         */
    01238     Kernel1D & initExplicitly(int left, int right)
    01239     {
    01240         vigra_precondition(left <= 0,
    01241                      "Kernel1D::initExplicitly(): left border must be <= 0.");
    01242         vigra_precondition(right >= 0,
    01243                      "Kernel1D::initExplicitly(): right border must be <= 0.");
    01244
    01245         right_ = right;
    01246         left_ = left;
    01247
    01248         kernel_.resize(right - left + 1);
    01249
    01250         return *this;
    01251     }
    01252
    01253         /** Get iterator to center of kernel
    01254
    01255             Postconditions:
    01256             \code
    01257
    01258             center()[left()] ... center()[right()] are valid kernel positions
    01259             \endcode
    01260         */
    01261     iterator center()
    01262     {
    01263         return kernel_.begin() - left();
    01264     }
    01265
    01266     const_iterator center() const
    01267     {
    01268         return kernel_.begin() - left();
    01269     }
    01270
    01271         /** Access kernel value at specified location.
    01272
    01273             Preconditions:
    01274             \code
    01275
    01276             left() <= location <= right()
    01277             \endcode
    01278         */
    01279     reference operator[](int location)
    01280     {
    01281         return kernel_[location - left()];
    01282     }
    01283
    01284     const_reference operator[](int location) const
    01285     {
    01286         return kernel_[location - left()];
    01287     }
    01288
    01289         /** left border of kernel (inclusive), always <= 0
    01290         */
    01291     int left() const { return left_; }
    01292
    01293         /** right border of kernel (inclusive), always >= 0
    01294         */
    01295     int right() const { return right_; }
    01296
    01297         /** size of kernel (right() - left() + 1)
    01298         */
    01299     int size() const { return right_ - left_ + 1; }
    01300
    01301         /** current border treatment mode
    01302         */
    01303     BorderTreatmentMode borderTreatment() const
    01304     { return border_treatment_; }
    01305
    01306         /** Set border treatment mode.
    01307         */
    01308     void setBorderTreatment( BorderTreatmentMode new_mode)
    01309     { border_treatment_ = new_mode; }
    01310
    01311         /** norm of kernel
    01312         */
    01313     value_type norm() const { return norm_; }
    01314
    01315         /** set a new norm and normalize kernel, use the normalization formula
    01316             for the given </tt>derivativeOrder</tt>.
    01317         */
    01318     void
    01319     normalize(value_type norm, unsigned int derivativeOrder = 0, double offset = 0.0);
    01320
    01321         /** normalize kernel to norm 1.
    01322         */
    01323     void
    01324     normalize()
    01325     {
    01326         normalize(one());
    01327     }
    01328
    01329         /** get a const accessor
    01330         */
    01331     ConstAccessor accessor() const { return ConstAccessor(); }
    01332
    01333         /** get an accessor
    01334         */
    01335     Accessor accessor() { return Accessor(); }
    01336
    01337   private:
    01338     InternalVector kernel_;
    01339     int left_, right_;
    01340     BorderTreatmentMode border_treatment_;
    01341     value_type norm_;
    01342 };
    01343
    01344 template <class ARITHTYPE>
    01345 void Kernel1D<ARITHTYPE>::normalize(value_type norm,
    01346                           unsigned int derivativeOrder,
    01347                           double offset)
    01348 {
    01349     typedef typename NumericTraits<value_type>::RealPromote TmpType;
    01350
    01351     // find kernel sum
    01352     Iterator k = kernel_.begin();
    01353     TmpType sum = NumericTraits<TmpType>::zero();
    01354
    01355     if(derivativeOrder == 0)
    01356     {
    01357         for(; k < kernel_.end(); ++k)
    01358         {
    01359             sum += *k;
    01360         }
    01361     }
    01362     else
    01363     {
    01364         unsigned int faculty = 1;
    01365         for(unsigned int i = 2; i <= derivativeOrder; ++i)
    01366             faculty *= i;
    01367         for(double x = left() + offset; k < kernel_.end(); ++x, ++k)
    01368         {
    01369             sum += *k * VIGRA_CSTD::pow(-x, int(derivativeOrder)) / faculty;
    01370         }
    01371     }
    01372
    01373     vigra_precondition(sum != NumericTraits<value_type>::zero(),
    01374                     "Kernel1D<ARITHTYPE>::normalize(): "
    01375                     "Cannot normalize a kernel with sum = 0");
    01376     // normalize
    01377     sum = norm / sum;
    01378     k = kernel_.begin();
    01379     for(; k != kernel_.end(); ++k)
    01380     {
    01381         *k = *k * sum;
    01382     }
    01383
    01384     norm_ = norm;
    01385 }
    01386
    01387 /***********************************************************************/
    01388
    01389 template <class ARITHTYPE>
    01390 void Kernel1D<ARITHTYPE>::initGaussian(double std_dev,
    01391                                        value_type norm)
    01392 {
    01393     vigra_precondition(std_dev >= 0.0,
    01394               "Kernel1D::initGaussian(): Standard deviation must be >= 0.");
    01395
    01396     if(std_dev > 0.0)
    01397     {
    01398         Gaussian<ARITHTYPE> gauss(std_dev);
    01399
    01400         // first calculate required kernel sizes
    01401         int radius = (int)(3.0 * std_dev + 0.5);
    01402         if(radius == 0)
    01403             radius = 1;
    01404
    01405         // allocate the kernel
    01406         kernel_.erase(kernel_.begin(), kernel_.end());
    01407         kernel_.reserve(radius*2+1);
    01408
    01409         for(ARITHTYPE x = -radius; x <= radius; ++x)
    01410         {
    01411             kernel_.push_back(gauss(x));
    01412         }
    01413         left_ = -radius;
    01414         right_ = radius;
    01415     }
    01416     else
    01417     {
    01418         kernel_.erase(kernel_.begin(), kernel_.end());
    01419         kernel_.push_back(1.0);
    01420         left_ = 0;
    01421         right_ = 0;
    01422     }
    01423
    01424     if(norm != 0.0)
    01425         normalize(norm);
    01426     else
    01427         norm_ = 1.0;
    01428
    01429     // best border treatment for Gaussians is BORDER_TREATMENT_CLIP
    01430     border_treatment_ = BORDER_TREATMENT_CLIP;
    01431 }
    01432
    01433 /***********************************************************************/
    01434
    01435 template <class ARITHTYPE>
    01436 void Kernel1D<ARITHTYPE>::initDiscreteGaussian(double std_dev,
    01437                                        value_type norm)
    01438 {
    01439     vigra_precondition(std_dev >= 0.0,
    01440               "Kernel1D::initDiscreteGaussian(): Standard deviation must be >= 0.");
    01441
    01442     if(std_dev > 0.0)
    01443     {
    01444         // first calculate required kernel sizes
    01445         int radius = (int)(3.0*std_dev + 0.5);
    01446         if(radius == 0)
    01447             radius = 1;
    01448
    01449         double f = 2.0 / std_dev / std_dev;
    01450
    01451         // allocate the working array
    01452         int maxIndex = (int)(2.0 * (radius + 5.0 * VIGRA_CSTD::sqrt((double)radius)) + 0.5);
    01453         InternalVector warray(maxIndex+1);
    01454         warray[maxIndex] = 0.0;
    01455         warray[maxIndex-1] = 1.0;
    01456
    01457         for(int i = maxIndex-2; i >= radius; --i)
    01458         {
    01459             warray[i] = warray[i+2] + f * (i+1) * warray[i+1];
    01460             if(warray[i] > 1.0e40)
    01461             {
    01462                 warray[i+1] /= warray[i];
    01463                 warray[i] = 1.0;
    01464             }
    01465         }
    01466
    01467         // the following rescaling ensures that the numbers stay in a sensible range
    01468         // during the rest of the iteration, so no other rescaling is needed
    01469         double er = VIGRA_CSTD::exp(-radius*radius / (2.0*std_dev*std_dev));
    01470         warray[radius+1] = er * warray[radius+1] / warray[radius];
    01471         warray[radius] = er;
    01472
    01473         for(int i = radius-1; i >= 0; --i)
    01474         {
    01475             warray[i] = warray[i+2] + f * (i+1) * warray[i+1];
    01476             er += warray[i];
    01477         }
    01478
    01479         double scale = norm / (2*er - warray[0]);
    01480
    01481         initExplicitly(-radius, radius);
    01482         iterator c = center();
    01483
    01484         for(int i=0; i<=radius; ++i)
    01485         {
    01486             c[i] = c[-i] = warray[i] * scale;
    01487         }
    01488     }
    01489     else
    01490     {
    01491         kernel_.erase(kernel_.begin(), kernel_.end());
    01492         kernel_.push_back(norm);
    01493         left_ = 0;
    01494         right_ = 0;
    01495     }
    01496
    01497     norm_ = norm;
    01498
    01499     // best border treatment for Gaussians is BORDER_TREATMENT_REFLECT
    01500     border_treatment_ = BORDER_TREATMENT_REFLECT;
    01501 }
    01502
    01503 /***********************************************************************/
    01504
    01505 template <class ARITHTYPE>
    01506 void
    01507 Kernel1D<ARITHTYPE>::initGaussianDerivative(double std_dev,
    01508                     int order,
    01509                     value_type norm)
    01510 {
    01511     vigra_precondition(order >= 0,
    01512               "Kernel1D::initGaussianDerivative(): Order must be >= 0.");
    01513
    01514     if(order == 0)
    01515     {
    01516         initGaussian(std_dev, norm);
    01517         return;
    01518     }
    01519
    01520     vigra_precondition(std_dev > 0.0,
    01521               "Kernel1D::initGaussianDerivative(): "
    01522               "Standard deviation must be > 0.");
    01523
    01524     Gaussian<ARITHTYPE> gauss(std_dev, order);
    01525
    01526     // first calculate required kernel sizes
    01527     int radius = (int)(3.0 * std_dev + 0.5 * order + 0.5);
    01528     if(radius == 0)
    01529         radius = 1;
    01530
    01531     // allocate the kernels
    01532     kernel_.clear();
    01533     kernel_.reserve(radius*2+1);
    01534
    01535     // fill the kernel and calculate the DC component
    01536     // introduced by truncation of the Geussian
    01537     ARITHTYPE dc = 0.0;
    01538     for(ARITHTYPE x = -radius; x <= radius; ++x)
    01539     {
    01540         kernel_.push_back(gauss(x));
    01541         dc += kernel_[kernel_.size()-1];
    01542     }
    01543     dc /= (2.0*radius + 1.0);
    01544
    01545     // remove DC, but only if kernel correction is permitted by a non-zero
    01546     // value for norm
    01547     if(norm != 0.0)
    01548     {
    01549         for(unsigned int i=0; i < kernel_.size(); ++i)
    01550         {
    01551             kernel_[i] -= dc;
    01552         }
    01553     }
    01554
    01555     left_ = -radius;
    01556     right_ = radius;
    01557
    01558     if(norm != 0.0)
    01559         normalize(norm, order);
    01560     else
    01561         norm_ = 1.0;
    01562
    01563     // best border treatment for Gaussian derivatives is
    01564     // BORDER_TREATMENT_REPEAT
    01565     border_treatment_ = BORDER_TREATMENT_REPEAT;
    01566 }
    01567
    01568 /***********************************************************************/
    01569
    01570 template <class ARITHTYPE>
    01571 void
    01572 Kernel1D<ARITHTYPE>::initBinomial(int radius,
    01573                                   value_type norm)
    01574 {
    01575     vigra_precondition(radius > 0,
    01576               "Kernel1D::initBinomial(): Radius must be > 0.");
    01577
    01578     // allocate the kernel
    01579     InternalVector kernel(radius*2+1);
    01580
    01581     int i,j;
    01582     for(i=0; i<radius*2+1; ++i) kernel[i] = 0;
    01583
    01584     // fill kernel
    01585     typename InternalVector::iterator x = kernel.begin() + radius;
    01586     x[radius] = 1.0;
    01587
    01588     for(j=radius-1; j>=-radius; --j)
    01589     {
    01590         for(i=j; i<radius; ++i)
    01591         {
    01592             x[i] = (x[i] + x[i+1]) / 2.0;
    01593         }
    01594         x[radius] /= 2.0;
    01595     }
    01596
    01597     // normalize
    01598     kernel_.erase(kernel_.begin(), kernel_.end());
    01599     kernel_.reserve(radius*2+1);
    01600
    01601     for(i=0; i<=radius*2+1; ++i)
    01602     {
    01603         kernel_.push_back(kernel[i] * norm);
    01604     }
    01605
    01606     left_ = -radius;
    01607     right_ = radius;
    01608     norm_ = norm;
    01609
    01610     // best border treatment for Binomial is BORDER_TREATMENT_REFLECT
    01611     border_treatment_ = BORDER_TREATMENT_REFLECT;
    01612 }
    01613
    01614 /***********************************************************************/
    01615
    01616 template <class ARITHTYPE>
    01617 void Kernel1D<ARITHTYPE>::initAveraging(int radius,
    01618                                         value_type norm)
    01619 {
    01620     vigra_precondition(radius > 0,
    01621               "Kernel1D::initAveraging(): Radius must be > 0.");
    01622
    01623     // calculate scaling
    01624     double scale = 1.0 / (radius * 2 + 1);
    01625
    01626     // normalize
    01627     kernel_.erase(kernel_.begin(), kernel_.end());
    01628     kernel_.reserve(radius*2+1);
    01629
    01630     for(int i=0; i<=radius*2+1; ++i)
    01631     {
    01632         kernel_.push_back(scale * norm);
    01633     }
    01634
    01635     left_ = -radius;
    01636     right_ = radius;
    01637     norm_ = norm;
    01638
    01639     // best border treatment for Averaging is BORDER_TREATMENT_CLIP
    01640     border_treatment_ = BORDER_TREATMENT_CLIP;
    01641 }
    01642
    01643 /***********************************************************************/
    01644
    01645 template <class ARITHTYPE>
    01646 void
    01647 Kernel1D<ARITHTYPE>::initSymmetricGradient(value_type norm)
    01648 {
    01649     kernel_.erase(kernel_.begin(), kernel_.end());
    01650     kernel_.reserve(3);
    01651
    01652     kernel_.push_back(0.5 * norm);
    01653     kernel_.push_back(0.0 * norm);
    01654     kernel_.push_back(-0.5 * norm);
    01655
    01656     left_ = -1;
    01657     right_ = 1;
    01658     norm_ = norm;
    01659
    01660     // best border treatment for SymmetricGradient is
    01661     // BORDER_TREATMENT_REPEAT
    01662     border_treatment_ = BORDER_TREATMENT_REPEAT;
    01663 }
    01664
    01665 /**************************************************************/
    01666 /*                                                            */
    01667 /*         Argument object factories for Kernel1D             */
    01668 /*                                                            */
    01669 /*     (documentation: see vigra/convolution.hxx)             */
    01670 /*                                                            */
    01671 /**************************************************************/
    01672
    01673 template <class KernelIterator, class KernelAccessor>
    01674 inline
    01675 tuple5<KernelIterator, KernelAccessor, int, int, BorderTreatmentMode>
    01676 kernel1d(KernelIterator ik, KernelAccessor ka,
    01677        int kleft, int kright, BorderTreatmentMode border)
    01678 {
    01679     return
    01680       tuple5<KernelIterator, KernelAccessor, int, int, BorderTreatmentMode>(
    01681                                                 ik, ka, kleft, kright, border);
    01682 }
    01683
    01684 template <class T>
    01685 inline
    01686 tuple5<typename Kernel1D<T>::const_iterator, typename Kernel1D<T>::ConstAccessor,
    01687        int, int, BorderTreatmentMode>
    01688 kernel1d(Kernel1D<T> const & k)
    01689
    01690 {
    01691     return
    01692         tuple5<typename Kernel1D<T>::const_iterator, typename Kernel1D<T>::ConstAccessor,
    01693                int, int, BorderTreatmentMode>(
    01694                                      k.center(),
    01695                                      k.accessor(),
    01696                                      k.left(), k.right(),
    01697                                      k.borderTreatment());
    01698 }
    01699
    01700 template <class T>
    01701 inline
    01702 tuple5<typename Kernel1D<T>::const_iterator, typename Kernel1D<T>::ConstAccessor,
    01703        int, int, BorderTreatmentMode>
    01704 kernel1d(Kernel1D<T> const & k, BorderTreatmentMode border)
    01705
    01706 {
    01707     return
    01708         tuple5<typename Kernel1D<T>::const_iterator, typename Kernel1D<T>::ConstAccessor,
    01709                int, int, BorderTreatmentMode>(
    01710                                      k.center(),
    01711                                      k.accessor(),
    01712                                      k.left(), k.right(),
    01713                                      border);
    01714 }
    01715
    01716
    01717 } // namespace vigra
    01718
    01719 #endif // VIGRA_SEPARABLECONVOLUTION_HXX

© Ullrich Köthe (koethe@informatik.uni-hamburg.de) Cognitive Systems Group, University of Hamburg, Germany | html generated using doxygen and Python VIGRA 1.4.0 (21 Dec 2005)