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     34 
     35 #include "precomp.hpp"
     36 #include <vector>
     37 
     38 namespace cv
     39 {
     40 
     41 static void magSpectrums( InputArray _src, OutputArray _dst)
     42 {
     43     Mat src = _src.getMat();
     44     int depth = src.depth(), cn = src.channels(), type = src.type();
     45     int rows = src.rows, cols = src.cols;
     46     int j, k;
     47 
     48     CV_Assert( type == CV_32FC1 || type == CV_32FC2 || type == CV_64FC1 || type == CV_64FC2 );
     49 
     50     if(src.depth() == CV_32F)
     51         _dst.create( src.rows, src.cols, CV_32FC1 );
     52     else
     53         _dst.create( src.rows, src.cols, CV_64FC1 );
     54 
     55     Mat dst = _dst.getMat();
     56     dst.setTo(0);//Mat elements are not equal to zero by default!
     57 
     58     bool is_1d = (rows == 1 || (cols == 1 && src.isContinuous() && dst.isContinuous()));
     59 
     60     if( is_1d )
     61         cols = cols + rows - 1, rows = 1;
     62 
     63     int ncols = cols*cn;
     64     int j0 = cn == 1;
     65     int j1 = ncols - (cols % 2 == 0 && cn == 1);
     66 
     67     if( depth == CV_32F )
     68     {
     69         const float* dataSrc = src.ptr<float>();
     70         float* dataDst = dst.ptr<float>();
     71 
     72         size_t stepSrc = src.step/sizeof(dataSrc[0]);
     73         size_t stepDst = dst.step/sizeof(dataDst[0]);
     74 
     75         if( !is_1d && cn == 1 )
     76         {
     77             for( k = 0; k < (cols % 2 ? 1 : 2); k++ )
     78             {
     79                 if( k == 1 )
     80                     dataSrc += cols - 1, dataDst += cols - 1;
     81                 dataDst[0] = dataSrc[0]*dataSrc[0];
     82                 if( rows % 2 == 0 )
     83                     dataDst[(rows-1)*stepDst] = dataSrc[(rows-1)*stepSrc]*dataSrc[(rows-1)*stepSrc];
     84 
     85                 for( j = 1; j <= rows - 2; j += 2 )
     86                 {
     87                     dataDst[j*stepDst] = (float)std::sqrt((double)dataSrc[j*stepSrc]*dataSrc[j*stepSrc] +
     88                                                           (double)dataSrc[(j+1)*stepSrc]*dataSrc[(j+1)*stepSrc]);
     89                 }
     90 
     91                 if( k == 1 )
     92                     dataSrc -= cols - 1, dataDst -= cols - 1;
     93             }
     94         }
     95 
     96         for( ; rows--; dataSrc += stepSrc, dataDst += stepDst )
     97         {
     98             if( is_1d && cn == 1 )
     99             {
    100                 dataDst[0] = dataSrc[0]*dataSrc[0];
    101                 if( cols % 2 == 0 )
    102                     dataDst[j1] = dataSrc[j1]*dataSrc[j1];
    103             }
    104 
    105             for( j = j0; j < j1; j += 2 )
    106             {
    107                 dataDst[j] = (float)std::sqrt((double)dataSrc[j]*dataSrc[j] + (double)dataSrc[j+1]*dataSrc[j+1]);
    108             }
    109         }
    110     }
    111     else
    112     {
    113         const double* dataSrc = src.ptr<double>();
    114         double* dataDst = dst.ptr<double>();
    115 
    116         size_t stepSrc = src.step/sizeof(dataSrc[0]);
    117         size_t stepDst = dst.step/sizeof(dataDst[0]);
    118 
    119         if( !is_1d && cn == 1 )
    120         {
    121             for( k = 0; k < (cols % 2 ? 1 : 2); k++ )
    122             {
    123                 if( k == 1 )
    124                     dataSrc += cols - 1, dataDst += cols - 1;
    125                 dataDst[0] = dataSrc[0]*dataSrc[0];
    126                 if( rows % 2 == 0 )
    127                     dataDst[(rows-1)*stepDst] = dataSrc[(rows-1)*stepSrc]*dataSrc[(rows-1)*stepSrc];
    128 
    129                 for( j = 1; j <= rows - 2; j += 2 )
    130                 {
    131                     dataDst[j*stepDst] = std::sqrt(dataSrc[j*stepSrc]*dataSrc[j*stepSrc] +
    132                                                    dataSrc[(j+1)*stepSrc]*dataSrc[(j+1)*stepSrc]);
    133                 }
    134 
    135                 if( k == 1 )
    136                     dataSrc -= cols - 1, dataDst -= cols - 1;
    137             }
    138         }
    139 
    140         for( ; rows--; dataSrc += stepSrc, dataDst += stepDst )
    141         {
    142             if( is_1d && cn == 1 )
    143             {
    144                 dataDst[0] = dataSrc[0]*dataSrc[0];
    145                 if( cols % 2 == 0 )
    146                     dataDst[j1] = dataSrc[j1]*dataSrc[j1];
    147             }
    148 
    149             for( j = j0; j < j1; j += 2 )
    150             {
    151                 dataDst[j] = std::sqrt(dataSrc[j]*dataSrc[j] + dataSrc[j+1]*dataSrc[j+1]);
    152             }
    153         }
    154     }
    155 }
    156 
    157 static void divSpectrums( InputArray _srcA, InputArray _srcB, OutputArray _dst, int flags, bool conjB)
    158 {
    159     Mat srcA = _srcA.getMat(), srcB = _srcB.getMat();
    160     int depth = srcA.depth(), cn = srcA.channels(), type = srcA.type();
    161     int rows = srcA.rows, cols = srcA.cols;
    162     int j, k;
    163 
    164     CV_Assert( type == srcB.type() && srcA.size() == srcB.size() );
    165     CV_Assert( type == CV_32FC1 || type == CV_32FC2 || type == CV_64FC1 || type == CV_64FC2 );
    166 
    167     _dst.create( srcA.rows, srcA.cols, type );
    168     Mat dst = _dst.getMat();
    169 
    170     bool is_1d = (flags & DFT_ROWS) || (rows == 1 || (cols == 1 &&
    171              srcA.isContinuous() && srcB.isContinuous() && dst.isContinuous()));
    172 
    173     if( is_1d && !(flags & DFT_ROWS) )
    174         cols = cols + rows - 1, rows = 1;
    175 
    176     int ncols = cols*cn;
    177     int j0 = cn == 1;
    178     int j1 = ncols - (cols % 2 == 0 && cn == 1);
    179 
    180     if( depth == CV_32F )
    181     {
    182         const float* dataA = srcA.ptr<float>();
    183         const float* dataB = srcB.ptr<float>();
    184         float* dataC = dst.ptr<float>();
    185         float eps = FLT_EPSILON; // prevent div0 problems
    186 
    187         size_t stepA = srcA.step/sizeof(dataA[0]);
    188         size_t stepB = srcB.step/sizeof(dataB[0]);
    189         size_t stepC = dst.step/sizeof(dataC[0]);
    190 
    191         if( !is_1d && cn == 1 )
    192         {
    193             for( k = 0; k < (cols % 2 ? 1 : 2); k++ )
    194             {
    195                 if( k == 1 )
    196                     dataA += cols - 1, dataB += cols - 1, dataC += cols - 1;
    197                 dataC[0] = dataA[0] / (dataB[0] + eps);
    198                 if( rows % 2 == 0 )
    199                     dataC[(rows-1)*stepC] = dataA[(rows-1)*stepA] / (dataB[(rows-1)*stepB] + eps);
    200                 if( !conjB )
    201                     for( j = 1; j <= rows - 2; j += 2 )
    202                     {
    203                         double denom = (double)dataB[j*stepB]*dataB[j*stepB] +
    204                                        (double)dataB[(j+1)*stepB]*dataB[(j+1)*stepB] + (double)eps;
    205 
    206                         double re = (double)dataA[j*stepA]*dataB[j*stepB] +
    207                                     (double)dataA[(j+1)*stepA]*dataB[(j+1)*stepB];
    208 
    209                         double im = (double)dataA[(j+1)*stepA]*dataB[j*stepB] -
    210                                     (double)dataA[j*stepA]*dataB[(j+1)*stepB];
    211 
    212                         dataC[j*stepC] = (float)(re / denom);
    213                         dataC[(j+1)*stepC] = (float)(im / denom);
    214                     }
    215                 else
    216                     for( j = 1; j <= rows - 2; j += 2 )
    217                     {
    218 
    219                         double denom = (double)dataB[j*stepB]*dataB[j*stepB] +
    220                                        (double)dataB[(j+1)*stepB]*dataB[(j+1)*stepB] + (double)eps;
    221 
    222                         double re = (double)dataA[j*stepA]*dataB[j*stepB] -
    223                                     (double)dataA[(j+1)*stepA]*dataB[(j+1)*stepB];
    224 
    225                         double im = (double)dataA[(j+1)*stepA]*dataB[j*stepB] +
    226                                     (double)dataA[j*stepA]*dataB[(j+1)*stepB];
    227 
    228                         dataC[j*stepC] = (float)(re / denom);
    229                         dataC[(j+1)*stepC] = (float)(im / denom);
    230                     }
    231                 if( k == 1 )
    232                     dataA -= cols - 1, dataB -= cols - 1, dataC -= cols - 1;
    233             }
    234         }
    235 
    236         for( ; rows--; dataA += stepA, dataB += stepB, dataC += stepC )
    237         {
    238             if( is_1d && cn == 1 )
    239             {
    240                 dataC[0] = dataA[0] / (dataB[0] + eps);
    241                 if( cols % 2 == 0 )
    242                     dataC[j1] = dataA[j1] / (dataB[j1] + eps);
    243             }
    244 
    245             if( !conjB )
    246                 for( j = j0; j < j1; j += 2 )
    247                 {
    248                     double denom = (double)(dataB[j]*dataB[j] + dataB[j+1]*dataB[j+1] + eps);
    249                     double re = (double)(dataA[j]*dataB[j] + dataA[j+1]*dataB[j+1]);
    250                     double im = (double)(dataA[j+1]*dataB[j] - dataA[j]*dataB[j+1]);
    251                     dataC[j] = (float)(re / denom);
    252                     dataC[j+1] = (float)(im / denom);
    253                 }
    254             else
    255                 for( j = j0; j < j1; j += 2 )
    256                 {
    257                     double denom = (double)(dataB[j]*dataB[j] + dataB[j+1]*dataB[j+1] + eps);
    258                     double re = (double)(dataA[j]*dataB[j] - dataA[j+1]*dataB[j+1]);
    259                     double im = (double)(dataA[j+1]*dataB[j] + dataA[j]*dataB[j+1]);
    260                     dataC[j] = (float)(re / denom);
    261                     dataC[j+1] = (float)(im / denom);
    262                 }
    263         }
    264     }
    265     else
    266     {
    267         const double* dataA = srcA.ptr<double>();
    268         const double* dataB = srcB.ptr<double>();
    269         double* dataC = dst.ptr<double>();
    270         double eps = DBL_EPSILON; // prevent div0 problems
    271 
    272         size_t stepA = srcA.step/sizeof(dataA[0]);
    273         size_t stepB = srcB.step/sizeof(dataB[0]);
    274         size_t stepC = dst.step/sizeof(dataC[0]);
    275 
    276         if( !is_1d && cn == 1 )
    277         {
    278             for( k = 0; k < (cols % 2 ? 1 : 2); k++ )
    279             {
    280                 if( k == 1 )
    281                     dataA += cols - 1, dataB += cols - 1, dataC += cols - 1;
    282                 dataC[0] = dataA[0] / (dataB[0] + eps);
    283                 if( rows % 2 == 0 )
    284                     dataC[(rows-1)*stepC] = dataA[(rows-1)*stepA] / (dataB[(rows-1)*stepB] + eps);
    285                 if( !conjB )
    286                     for( j = 1; j <= rows - 2; j += 2 )
    287                     {
    288                         double denom = dataB[j*stepB]*dataB[j*stepB] +
    289                                        dataB[(j+1)*stepB]*dataB[(j+1)*stepB] + eps;
    290 
    291                         double re = dataA[j*stepA]*dataB[j*stepB] +
    292                                     dataA[(j+1)*stepA]*dataB[(j+1)*stepB];
    293 
    294                         double im = dataA[(j+1)*stepA]*dataB[j*stepB] -
    295                                     dataA[j*stepA]*dataB[(j+1)*stepB];
    296 
    297                         dataC[j*stepC] = re / denom;
    298                         dataC[(j+1)*stepC] = im / denom;
    299                     }
    300                 else
    301                     for( j = 1; j <= rows - 2; j += 2 )
    302                     {
    303                         double denom = dataB[j*stepB]*dataB[j*stepB] +
    304                                        dataB[(j+1)*stepB]*dataB[(j+1)*stepB] + eps;
    305 
    306                         double re = dataA[j*stepA]*dataB[j*stepB] -
    307                                     dataA[(j+1)*stepA]*dataB[(j+1)*stepB];
    308 
    309                         double im = dataA[(j+1)*stepA]*dataB[j*stepB] +
    310                                     dataA[j*stepA]*dataB[(j+1)*stepB];
    311 
    312                         dataC[j*stepC] = re / denom;
    313                         dataC[(j+1)*stepC] = im / denom;
    314                     }
    315                 if( k == 1 )
    316                     dataA -= cols - 1, dataB -= cols - 1, dataC -= cols - 1;
    317             }
    318         }
    319 
    320         for( ; rows--; dataA += stepA, dataB += stepB, dataC += stepC )
    321         {
    322             if( is_1d && cn == 1 )
    323             {
    324                 dataC[0] = dataA[0] / (dataB[0] + eps);
    325                 if( cols % 2 == 0 )
    326                     dataC[j1] = dataA[j1] / (dataB[j1] + eps);
    327             }
    328 
    329             if( !conjB )
    330                 for( j = j0; j < j1; j += 2 )
    331                 {
    332                     double denom = dataB[j]*dataB[j] + dataB[j+1]*dataB[j+1] + eps;
    333                     double re = dataA[j]*dataB[j] + dataA[j+1]*dataB[j+1];
    334                     double im = dataA[j+1]*dataB[j] - dataA[j]*dataB[j+1];
    335                     dataC[j] = re / denom;
    336                     dataC[j+1] = im / denom;
    337                 }
    338             else
    339                 for( j = j0; j < j1; j += 2 )
    340                 {
    341                     double denom = dataB[j]*dataB[j] + dataB[j+1]*dataB[j+1] + eps;
    342                     double re = dataA[j]*dataB[j] - dataA[j+1]*dataB[j+1];
    343                     double im = dataA[j+1]*dataB[j] + dataA[j]*dataB[j+1];
    344                     dataC[j] = re / denom;
    345                     dataC[j+1] = im / denom;
    346                 }
    347         }
    348     }
    349 
    350 }
    351 
    352 static void fftShift(InputOutputArray _out)
    353 {
    354     Mat out = _out.getMat();
    355 
    356     if(out.rows == 1 && out.cols == 1)
    357     {
    358         // trivially shifted.
    359         return;
    360     }
    361 
    362     std::vector<Mat> planes;
    363     split(out, planes);
    364 
    365     int xMid = out.cols >> 1;
    366     int yMid = out.rows >> 1;
    367 
    368     bool is_1d = xMid == 0 || yMid == 0;
    369 
    370     if(is_1d)
    371     {
    372         xMid = xMid + yMid;
    373 
    374         for(size_t i = 0; i < planes.size(); i++)
    375         {
    376             Mat tmp;
    377             Mat half0(planes[i], Rect(0, 0, xMid, 1));
    378             Mat half1(planes[i], Rect(xMid, 0, xMid, 1));
    379 
    380             half0.copyTo(tmp);
    381             half1.copyTo(half0);
    382             tmp.copyTo(half1);
    383         }
    384     }
    385     else
    386     {
    387         for(size_t i = 0; i < planes.size(); i++)
    388         {
    389             // perform quadrant swaps...
    390             Mat tmp;
    391             Mat q0(planes[i], Rect(0,    0,    xMid, yMid));
    392             Mat q1(planes[i], Rect(xMid, 0,    xMid, yMid));
    393             Mat q2(planes[i], Rect(0,    yMid, xMid, yMid));
    394             Mat q3(planes[i], Rect(xMid, yMid, xMid, yMid));
    395 
    396             q0.copyTo(tmp);
    397             q3.copyTo(q0);
    398             tmp.copyTo(q3);
    399 
    400             q1.copyTo(tmp);
    401             q2.copyTo(q1);
    402             tmp.copyTo(q2);
    403         }
    404     }
    405 
    406     merge(planes, out);
    407 }
    408 
    409 static Point2d weightedCentroid(InputArray _src, cv::Point peakLocation, cv::Size weightBoxSize, double* response)
    410 {
    411     Mat src = _src.getMat();
    412 
    413     int type = src.type();
    414     CV_Assert( type == CV_32FC1 || type == CV_64FC1 );
    415 
    416     int minr = peakLocation.y - (weightBoxSize.height >> 1);
    417     int maxr = peakLocation.y + (weightBoxSize.height >> 1);
    418     int minc = peakLocation.x - (weightBoxSize.width  >> 1);
    419     int maxc = peakLocation.x + (weightBoxSize.width  >> 1);
    420 
    421     Point2d centroid;
    422     double sumIntensity = 0.0;
    423 
    424     // clamp the values to min and max if needed.
    425     if(minr < 0)
    426     {
    427         minr = 0;
    428     }
    429 
    430     if(minc < 0)
    431     {
    432         minc = 0;
    433     }
    434 
    435     if(maxr > src.rows - 1)
    436     {
    437         maxr = src.rows - 1;
    438     }
    439 
    440     if(maxc > src.cols - 1)
    441     {
    442         maxc = src.cols - 1;
    443     }
    444 
    445     if(type == CV_32FC1)
    446     {
    447         const float* dataIn = src.ptr<float>();
    448         dataIn += minr*src.cols;
    449         for(int y = minr; y <= maxr; y++)
    450         {
    451             for(int x = minc; x <= maxc; x++)
    452             {
    453                 centroid.x   += (double)x*dataIn[x];
    454                 centroid.y   += (double)y*dataIn[x];
    455                 sumIntensity += (double)dataIn[x];
    456             }
    457 
    458             dataIn += src.cols;
    459         }
    460     }
    461     else
    462     {
    463         const double* dataIn = src.ptr<double>();
    464         dataIn += minr*src.cols;
    465         for(int y = minr; y <= maxr; y++)
    466         {
    467             for(int x = minc; x <= maxc; x++)
    468             {
    469                 centroid.x   += (double)x*dataIn[x];
    470                 centroid.y   += (double)y*dataIn[x];
    471                 sumIntensity += dataIn[x];
    472             }
    473 
    474             dataIn += src.cols;
    475         }
    476     }
    477 
    478     if(response)
    479         *response = sumIntensity;
    480 
    481     sumIntensity += DBL_EPSILON; // prevent div0 problems...
    482 
    483     centroid.x /= sumIntensity;
    484     centroid.y /= sumIntensity;
    485 
    486     return centroid;
    487 }
    488 
    489 }
    490 
    491 cv::Point2d cv::phaseCorrelate(InputArray _src1, InputArray _src2, InputArray _window, double* response)
    492 {
    493     Mat src1 = _src1.getMat();
    494     Mat src2 = _src2.getMat();
    495     Mat window = _window.getMat();
    496 
    497     CV_Assert( src1.type() == src2.type());
    498     CV_Assert( src1.type() == CV_32FC1 || src1.type() == CV_64FC1 );
    499     CV_Assert( src1.size == src2.size);
    500 
    501     if(!window.empty())
    502     {
    503         CV_Assert( src1.type() == window.type());
    504         CV_Assert( src1.size == window.size);
    505     }
    506 
    507     int M = getOptimalDFTSize(src1.rows);
    508     int N = getOptimalDFTSize(src1.cols);
    509 
    510     Mat padded1, padded2, paddedWin;
    511 
    512     if(M != src1.rows || N != src1.cols)
    513     {
    514         copyMakeBorder(src1, padded1, 0, M - src1.rows, 0, N - src1.cols, BORDER_CONSTANT, Scalar::all(0));
    515         copyMakeBorder(src2, padded2, 0, M - src2.rows, 0, N - src2.cols, BORDER_CONSTANT, Scalar::all(0));
    516 
    517         if(!window.empty())
    518         {
    519             copyMakeBorder(window, paddedWin, 0, M - window.rows, 0, N - window.cols, BORDER_CONSTANT, Scalar::all(0));
    520         }
    521     }
    522     else
    523     {
    524         padded1 = src1;
    525         padded2 = src2;
    526         paddedWin = window;
    527     }
    528 
    529     Mat FFT1, FFT2, P, Pm, C;
    530 
    531     // perform window multiplication if available
    532     if(!paddedWin.empty())
    533     {
    534         // apply window to both images before proceeding...
    535         multiply(paddedWin, padded1, padded1);
    536         multiply(paddedWin, padded2, padded2);
    537     }
    538 
    539     // execute phase correlation equation
    540     // Reference: http://en.wikipedia.org/wiki/Phase_correlation
    541     dft(padded1, FFT1, DFT_REAL_OUTPUT);
    542     dft(padded2, FFT2, DFT_REAL_OUTPUT);
    543 
    544     mulSpectrums(FFT1, FFT2, P, 0, true);
    545 
    546     magSpectrums(P, Pm);
    547     divSpectrums(P, Pm, C, 0, false); // FF* / |FF*| (phase correlation equation completed here...)
    548 
    549     idft(C, C); // gives us the nice peak shift location...
    550 
    551     fftShift(C); // shift the energy to the center of the frame.
    552 
    553     // locate the highest peak
    554     Point peakLoc;
    555     minMaxLoc(C, NULL, NULL, NULL, &peakLoc);
    556 
    557     // get the phase shift with sub-pixel accuracy, 5x5 window seems about right here...
    558     Point2d t;
    559     t = weightedCentroid(C, peakLoc, Size(5, 5), response);
    560 
    561     // max response is M*N (not exactly, might be slightly larger due to rounding errors)
    562     if(response)
    563         *response /= M*N;
    564 
    565     // adjust shift relative to image center...
    566     Point2d center((double)padded1.cols / 2.0, (double)padded1.rows / 2.0);
    567 
    568     return (center - t);
    569 }
    570 
    571 
    572 void cv::createHanningWindow(OutputArray _dst, cv::Size winSize, int type)
    573 {
    574     CV_Assert( type == CV_32FC1 || type == CV_64FC1 );
    575 
    576     _dst.create(winSize, type);
    577     Mat dst = _dst.getMat();
    578 
    579     int rows = dst.rows, cols = dst.cols;
    580 
    581     AutoBuffer<double> _wc(cols);
    582     double * const wc = (double *)_wc;
    583 
    584     double coeff0 = 2.0 * CV_PI / (double)(cols - 1), coeff1 = 2.0f * CV_PI / (double)(rows - 1);
    585     for(int j = 0; j < cols; j++)
    586         wc[j] = 0.5 * (1.0 - cos(coeff0 * j));
    587 
    588     if(dst.depth() == CV_32F)
    589     {
    590         for(int i = 0; i < rows; i++)
    591         {
    592             float* dstData = dst.ptr<float>(i);
    593             double wr = 0.5 * (1.0 - cos(coeff1 * i));
    594             for(int j = 0; j < cols; j++)
    595                 dstData[j] = (float)(wr * wc[j]);
    596         }
    597     }
    598     else
    599     {
    600         for(int i = 0; i < rows; i++)
    601         {
    602             double* dstData = dst.ptr<double>(i);
    603             double wr = 0.5 * (1.0 - cos(coeff1 * i));
    604             for(int j = 0; j < cols; j++)
    605                 dstData[j] = wr * wc[j];
    606         }
    607     }
    608 
    609     // perform batch sqrt for SSE performance gains
    610     cv::sqrt(dst, dst);
    611 }
    612