]> rtime.felk.cvut.cz Git - hercules2020/kcf.git/blobdiff - src/kcf.cpp
Cleaned FFTW version
[hercules2020/kcf.git] / src / kcf.cpp
index ca00a574158b006b09534faa021c1b61ebb20c90..bb94a5390cbd770b0ece4464e1d6dc0b4aa1f878 100644 (file)
@@ -7,7 +7,7 @@
 #ifdef FFTW
   #include "fft_fftw.h"
   #define FFT Fftw
-#elif CUFFT
+#elif defined(CUFFT)
   #include "fft_cufft.h"
   #define FFT cuFFT
 #else
@@ -34,12 +34,20 @@ KCF_Tracker::~KCF_Tracker()
 {
     delete &fft;
 #ifdef CUFFT
-    CudaSafeCall(cudaFreeHost(xf_sqr_norm));
-    CudaSafeCall(cudaFreeHost(yf_sqr_norm));
-    CudaSafeCall(cudaFree(gauss_corr_res));
+    for (int i = 0;i < p_num_scales;++i) {
+        CudaSafeCall(cudaFreeHost(scale_vars[i].xf_sqr_norm));
+        CudaSafeCall(cudaFreeHost(scale_vars[i].yf_sqr_norm));
+        CudaSafeCall(cudaFreeHost(scale_vars[i].data_i_1ch));
+        CudaSafeCall(cudaFreeHost(scale_vars[i].data_i_features));
+        CudaSafeCall(cudaFree(scale_vars[i].gauss_corr_res));
+        CudaSafeCall(cudaFreeHost(scale_vars[i].rot_labels_data));
+        CudaSafeCall(cudaFreeHost(scale_vars[i].data_features));
+    }
 #else
-    free(xf_sqr_norm);
-    free(yf_sqr_norm);
+    for (int i = 0;i < p_num_scales;++i) {
+        free(scale_vars[i].xf_sqr_norm);
+        free(scale_vars[i].yf_sqr_norm);
+    }
 #endif
 }
 
@@ -132,29 +140,17 @@ void KCF_Tracker::init(cv::Mat &img, const cv::Rect & bbox, int fit_size_x, int
     else
         p_scales.push_back(1.);
 
-#ifdef CUFFT
-    if (p_windows_size[1]/p_cell_size*(p_windows_size[0]/p_cell_size/2+1) > 1024) {
-        std::cerr << "Window after forward FFT is too big for CUDA kernels. Plese use -f to set "
-        "the window dimensions so its size is less or equal to " << 1024*p_cell_size*p_cell_size*2+1 <<
-        " pixels . Currently the size of the window is: " <<  p_windows_size[0] << "x" <<  p_windows_size[1] <<
-        " which is  " <<  p_windows_size[0]*p_windows_size[1] << " pixels. " << std::endl;
-        std::exit(EXIT_FAILURE);
+    for (int i = 0;i<p_num_scales;++i) {
+        scale_vars.push_back(Scale_vars());
     }
 
-    if (m_use_linearkernel){
-        std::cerr << "cuFFT supports only Gaussian kernel." << std::endl;
-        std::exit(EXIT_FAILURE);
-    }
-    cudaSetDeviceFlags(cudaDeviceMapHost);
-    CudaSafeCall(cudaHostAlloc((void**)&xf_sqr_norm, p_num_scales*sizeof(float), cudaHostAllocMapped));
-    CudaSafeCall(cudaHostGetDevicePointer((void**)&xf_sqr_norm_d, (void*)xf_sqr_norm, 0));
+    p_num_of_feats = 31;
+    if(m_use_color) p_num_of_feats += 3;
+    if(m_use_cnfeat) p_num_of_feats += 10;
+    p_roi_width = p_windows_size[0]/p_cell_size;
+    p_roi_height = p_windows_size[1]/p_cell_size;
 
-    CudaSafeCall(cudaHostAlloc((void**)&yf_sqr_norm, sizeof(float), cudaHostAllocMapped));
-    CudaSafeCall(cudaHostGetDevicePointer((void**)&yf_sqr_norm_d, (void*)yf_sqr_norm, 0));
-#else
-    xf_sqr_norm = (float*) malloc(p_num_scales*sizeof(float));
-    yf_sqr_norm = (float*) malloc(sizeof(float));
-#endif
+    init_scale_vars();
 
     p_current_scale = 1.;
 
@@ -169,24 +165,23 @@ void KCF_Tracker::init(cv::Mat &img, const cv::Rect & bbox, int fit_size_x, int
 
     p_output_sigma = std::sqrt(p_pose.w*p_pose.h) * p_output_sigma_factor / static_cast<double>(p_cell_size);
 
-    //window weights, i.e. labels
-    p_num_of_feats = 31;
-    if(m_use_color) p_num_of_feats += 3;
-    if(m_use_cnfeat) p_num_of_feats += 10;
-    p_roi_width = p_windows_size[0]/p_cell_size;
-    p_roi_height = p_windows_size[1]/p_cell_size;
-
     fft.init(p_windows_size[0]/p_cell_size, p_windows_size[1]/p_cell_size, p_num_of_feats, p_num_scales, m_use_big_batch);
-    p_yf = fft.forward(gaussian_shaped_labels(p_output_sigma, p_windows_size[0]/p_cell_size, p_windows_size[1]/p_cell_size));
     fft.set_window(cosine_window_function(p_windows_size[0]/p_cell_size, p_windows_size[1]/p_cell_size));
 
-#ifdef CUFFT
-      CudaSafeCall(cudaMalloc((void**)&gauss_corr_res, (p_windows_size[0]/p_cell_size)*(p_windows_size[1]/p_cell_size)*p_num_scales*sizeof(float)));
-#endif
+    scale_vars[0].flag = Tracker_flags::TRACKER_INIT;
+    //window weights, i.e. labels
+    gaussian_shaped_labels(scale_vars[0], p_output_sigma, p_windows_size[0]/p_cell_size, p_windows_size[1]/p_cell_size);
+    DEBUG_PRINTM(scale_vars[0].rot_labels);
+
+    fft.forward(scale_vars[0]);
+    DEBUG_PRINTM(p_yf);
+
     //obtain a sub-window for training initial model
-    std::vector<cv::Mat> path_feat = get_features(input_rgb, input_gray, p_pose.cx, p_pose.cy, p_windows_size[0], p_windows_size[1]);
-    p_model_xf = fft.forward_window(path_feat);
+    get_features(input_rgb, input_gray, p_pose.cx, p_pose.cy, p_windows_size[0], p_windows_size[1], scale_vars[0]);
+    fft.forward_window(scale_vars[0]);
     DEBUG_PRINTM(p_model_xf);
+    scale_vars[0].flag = Tracker_flags::AUTO_CORRELATION;
+
 
     if (m_use_linearkernel) {
         ComplexMat xfconj = p_model_xf.conj();
@@ -194,11 +189,11 @@ void KCF_Tracker::init(cv::Mat &img, const cv::Rect & bbox, int fit_size_x, int
         p_model_alphaf_den = (p_model_xf * xfconj);
     } else {
         //Kernel Ridge Regression, calculate alphas (in Fourier domain)
-        ComplexMat kf = gaussian_correlation(p_model_xf, p_model_xf, p_kernel_sigma, true);
-        DEBUG_PRINTM(kf);
-        p_model_alphaf_num = p_yf * kf;
+        gaussian_correlation(scale_vars[0], p_model_xf, p_model_xf, p_kernel_sigma, true);
+        DEBUG_PRINTM(scale_vars[0].kf);
+        p_model_alphaf_num = p_yf * scale_vars[0].kf;
         DEBUG_PRINTM(p_model_alphaf_num);
-        p_model_alphaf_den = kf * (kf + p_lambda);
+        p_model_alphaf_den = scale_vars[0].kf * (scale_vars[0].kf + p_lambda);
         DEBUG_PRINTM(p_model_alphaf_den);
     }
     p_model_alphaf = p_model_alphaf_num / p_model_alphaf_den;
@@ -206,6 +201,110 @@ void KCF_Tracker::init(cv::Mat &img, const cv::Rect & bbox, int fit_size_x, int
 //        p_model_alphaf = p_yf / (kf + p_lambda);   //equation for fast training
 }
 
+void KCF_Tracker::init_scale_vars()
+{
+    double alloc_size;
+
+#ifdef CUFFT
+    if (p_windows_size[1]/p_cell_size*(p_windows_size[0]/p_cell_size/2+1) > 1024) {
+        std::cerr << "Window after forward FFT is too big for CUDA kernels. Plese use -f to set "
+        "the window dimensions so its size is less or equal to " << 1024*p_cell_size*p_cell_size*2+1 <<
+        " pixels . Currently the size of the window is: " <<  p_windows_size[0] << "x" <<  p_windows_size[1] <<
+        " which is  " <<  p_windows_size[0]*p_windows_size[1] << " pixels. " << std::endl;
+        std::exit(EXIT_FAILURE);
+    }
+
+    if (m_use_linearkernel){
+        std::cerr << "cuFFT supports only Gaussian kernel." << std::endl;
+        std::exit(EXIT_FAILURE);
+    }
+    cudaSetDeviceFlags(cudaDeviceMapHost);
+
+    for (int i = 0;i<p_num_scales;++i) {
+        alloc_size = p_windows_size[0]/p_cell_size*p_windows_size[1]/p_cell_size*sizeof(cufftReal);
+        CudaSafeCall(cudaHostAlloc((void**)&scale_vars[i].data_i_1ch, alloc_size, cudaHostAllocMapped));
+        CudaSafeCall(cudaHostGetDevicePointer((void**)&scale_vars[i].data_i_1ch_d, (void*)scale_vars[i].data_i_1ch, 0));
+
+        alloc_size = p_windows_size[0]/p_cell_size*p_windows_size[1]/p_cell_size*p_num_of_feats*sizeof(cufftReal);
+        CudaSafeCall(cudaHostAlloc((void**)&scale_vars[i].data_i_features, alloc_size, cudaHostAllocMapped));
+        CudaSafeCall(cudaHostGetDevicePointer((void**)&scale_vars[i].data_i_features_d, (void*)scale_vars[i].data_i_features, 0));
+
+
+        scale_vars[i].ifft2_res = cv::Mat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, CV_32FC(p_num_of_feats), scale_vars[i].data_i_features);
+        scale_vars[i].response = cv::Mat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, CV_32FC1, scale_vars[i].data_i_1ch);
+
+        scale_vars[i].zf = ComplexMat(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, p_num_of_feats);
+        scale_vars[i].kzf = ComplexMat(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, 1);
+        scale_vars[i].kf = ComplexMat(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, 1);
+
+#ifdef BIG_BATCH
+        alloc_size = p_num_of_feats;
+#else
+        alloc_size = 1;
+#endif
+
+        CudaSafeCall(cudaHostAlloc((void**)&scale_vars[i].xf_sqr_norm, alloc_size*sizeof(float), cudaHostAllocMapped));
+        CudaSafeCall(cudaHostGetDevicePointer((void**)&scale_vars[i].xf_sqr_norm_d, (void*)scale_vars[i].xf_sqr_norm, 0));
+
+        CudaSafeCall(cudaHostAlloc((void**)&scale_vars[i].yf_sqr_norm, sizeof(float), cudaHostAllocMapped));
+        CudaSafeCall(cudaHostGetDevicePointer((void**)&scale_vars[i].yf_sqr_norm_d, (void*)scale_vars[i].yf_sqr_norm, 0));
+
+        alloc_size =(p_windows_size[0]/p_cell_size)*(p_windows_size[1]/p_cell_size)*alloc_size*sizeof(float);
+        CudaSafeCall(cudaMalloc((void**)&scale_vars[i].gauss_corr_res, alloc_size));
+        scale_vars[i].in_all = cv::Mat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, CV_32FC1, scale_vars[i].gauss_corr_res);
+
+        alloc_size = (p_windows_size[0]/p_cell_size)*(p_windows_size[1]/p_cell_size)*alloc_size*sizeof(float);
+        CudaSafeCall(cudaHostAlloc((void**)&scale_vars[i].rot_labels_data, alloc_size, cudaHostAllocMapped));
+        CudaSafeCall(cudaHostGetDevicePointer((void**)&scale_vars[i].rot_labels_data_d, (void*)scale_vars[i].rot_labels_data, 0));
+        scale_vars[i].rot_labels = cv::Mat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, CV_32FC1, scale_vars[i].rot_labels_data);
+
+        alloc_size = (p_windows_size[0]/p_cell_size)*((p_windows_size[1]/p_cell_size)*p_num_of_feats)*sizeof(cufftReal);
+        CudaSafeCall(cudaHostAlloc((void**)&scale_vars[i].data_features, alloc_size, cudaHostAllocMapped));
+        CudaSafeCall(cudaHostGetDevicePointer((void**)&scale_vars[i].data_features_d, (void*)scale_vars[i].data_features, 0));
+        scale_vars[i].fw_all = cv::Mat((p_windows_size[1]/p_cell_size)*p_num_of_feats, p_windows_size[0]/p_cell_size, CV_32F, scale_vars[i].data_features);
+    }
+#else
+if(m_use_big_batch)
+        alloc_size = p_num_of_feats;
+else
+        alloc_size = 1;
+
+    for (int i = 0;i<p_num_scales;++i) {
+        scale_vars[i].xf_sqr_norm = (float*) malloc(alloc_size*sizeof(float));
+        scale_vars[i].yf_sqr_norm = (float*) malloc(sizeof(float));
+
+        scale_vars[i].patch_feats.reserve(p_num_of_feats);
+#ifdef FFTW
+        scale_vars[i].ifft2_res = cv::Mat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, CV_32FC(p_num_of_feats));
+        scale_vars[i].response = cv::Mat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, CV_32FC1);
+
+        scale_vars[i].zf = ComplexMat(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, p_num_of_feats);
+        scale_vars[i].kzf = ComplexMat(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, 1);
+        scale_vars[i].kf = ComplexMat(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, 1);
+
+        scale_vars[i].in_all = cv::Mat((p_windows_size[1]/p_cell_size)*p_num_of_feats, p_windows_size[0]/p_cell_size, CV_32F);
+        scale_vars[i].fw_all = cv::Mat((p_windows_size[1]/p_cell_size)*p_num_of_feats, p_windows_size[0]/p_cell_size, CV_32F);
+#else
+        scale_vars[i].zf = ComplexMat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, p_num_of_feats);
+        //We use scale_vars[0] for updating the tracker, so we only allocate memory for  its xf only.
+        if (i==0)
+            scale_vars[i].xf = ComplexMat(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, p_num_of_feats);
+#endif
+    }
+#endif
+#if defined(FFTW) || defined(CUFFT)
+    p_model_xf.create(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, p_num_of_feats);
+    p_yf.create(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, 1);
+    //We use scale_vars[0] for updating the tracker, so we only allocate memory for  its xf only.
+    scale_vars[0].xf.create(p_windows_size[1]/p_cell_size, (p_windows_size[0]/p_cell_size)/2+1, p_num_of_feats);
+#else
+    p_model_xf.create(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, p_num_of_feats);
+    p_yf.create(p_windows_size[1]/p_cell_size, p_windows_size[0]/p_cell_size, 1);
+#endif
+    scale_vars[0].p_model_xf_ptr = & p_model_xf;
+    scale_vars[0].p_yf_ptr = & p_yf;
+}
+
 void KCF_Tracker::setTrackerPose(BBox_c &bbox, cv::Mat & img, int fit_size_x, int fit_size_y)
 {
     init(img, bbox.get_rect(), fit_size_x, fit_size_y);
@@ -271,147 +370,57 @@ void KCF_Tracker::track(cv::Mat &img)
         }
     }
 
-
-    std::vector<cv::Mat> patch_feat;
     double max_response = -1.;
-    cv::Mat max_response_map;
-    cv::Point2i max_response_pt;
     int scale_index = 0;
-    std::vector<double> scale_responses;
+    cv::Point2i *max_response_pt = nullptr;
+    cv::Mat *max_response_map = nullptr;
 
-    if (m_use_multithreading){
-        std::vector<std::future<cv::Mat>> async_res(p_scales.size());
-        for (size_t i = 0; i < p_scales.size(); ++i) {
+    if(m_use_multithreading) {
+        std::vector<std::future<void>> async_res(p_scales.size());
+        for (size_t i = 0; i < scale_vars.size(); ++i) {
             async_res[i] = std::async(std::launch::async,
-                                      [this, &input_gray, &input_rgb, i]() -> cv::Mat
-                                      {
-                                          std::vector<cv::Mat> patch_feat_async = get_features(input_rgb, input_gray, this->p_pose.cx, this->p_pose.cy, this->p_windows_size[0],
-                                                                                               this->p_windows_size[1], this->p_current_scale * this->p_scales[i]);
-                                          ComplexMat zf = fft.forward_window(patch_feat_async);
-                                          if (m_use_linearkernel)
-                                              return fft.inverse((p_model_alphaf * zf).sum_over_channels());
-                                          else {
-                                              ComplexMat kzf = gaussian_correlation(zf, this->p_model_xf, this->p_kernel_sigma);
-                                              return fft.inverse(this->p_model_alphaf * kzf);
-                                          }
-                                      });
+                                [this, &input_gray, &input_rgb, i]() -> void
+                                {return scale_track(this->scale_vars[i], input_rgb, input_gray, this->p_scales[i]);});
         }
-
         for (size_t i = 0; i < p_scales.size(); ++i) {
-            // wait for result
             async_res[i].wait();
-            cv::Mat response = async_res[i].get();
-
-            double min_val, max_val;
-            cv::Point2i min_loc, max_loc;
-            cv::minMaxLoc(response, &min_val, &max_val, &min_loc, &max_loc);
-
-            double weight = p_scales[i] < 1. ? p_scales[i] : 1./p_scales[i];
-            if (max_val*weight > max_response) {
-                max_response = max_val*weight;
-                max_response_map = response;
-                max_response_pt = max_loc;
+            if (this->scale_vars[i].max_response > max_response) {
+                max_response = this->scale_vars[i].max_response;
+                max_response_pt = & this->scale_vars[i].max_loc;
+                max_response_map = & this->scale_vars[i].response;
                 scale_index = i;
             }
-            scale_responses.push_back(max_val*weight);
-        }
-    } else if (m_use_big_batch){
-#pragma omp parallel for ordered
-        for (size_t i = 0; i < p_scales.size(); ++i) {
-            std::vector<cv::Mat> tmp = get_features(input_rgb, input_gray, p_pose.cx, p_pose.cy, p_windows_size[0], p_windows_size[1], p_current_scale * p_scales[i]);
-#pragma omp ordered
-            patch_feat.insert(std::end(patch_feat), std::begin(tmp), std::end(tmp));
-        }
-        ComplexMat zf = fft.forward_window(patch_feat);
-        DEBUG_PRINTM(zf);
-        cv::Mat response;
-
-        if (m_use_linearkernel)
-            response = fft.inverse((zf.mul2(p_model_alphaf)).sum_over_channels());
-        else {
-            ComplexMat kzf = gaussian_correlation(zf, p_model_xf, p_kernel_sigma);
-            DEBUG_PRINTM(p_model_alphaf);
-            DEBUG_PRINTM(kzf);
-            response = fft.inverse(kzf.mul(p_model_alphaf));
-        }
-        DEBUG_PRINTM(response);
-        std::vector<cv::Mat> scales;
-        cv::split(response,scales);
-
-        /* target location is at the maximum response. we must take into
-           account the fact that, if the target doesn't move, the peak
-           will appear at the top-left corner, not at the center (this is
-           discussed in the paper). the responses wrap around cyclically. */
-        for (size_t i = 0; i < p_scales.size(); ++i) {
-            double min_val, max_val;
-            cv::Point2i min_loc, max_loc;
-            cv::minMaxLoc(scales[i], &min_val, &max_val, &min_loc, &max_loc);
-            DEBUG_PRINT(max_loc);
-
-            double weight = p_scales[i] < 1. ? p_scales[i] : 1./p_scales[i];
-
-            if (max_val*weight > max_response) {
-                max_response = max_val*weight;
-                max_response_map = scales[i];
-                max_response_pt = max_loc;
-                scale_index = i;
-            }
-            scale_responses.push_back(max_val*weight);
         }
     } else {
-#pragma omp parallel for ordered  private(patch_feat) schedule(dynamic)
-        for (size_t i = 0; i < p_scales.size(); ++i) {
-            patch_feat = get_features(input_rgb, input_gray, p_pose.cx, p_pose.cy, p_windows_size[0], p_windows_size[1], p_current_scale * p_scales[i]);
-            ComplexMat zf = fft.forward_window(patch_feat);
-            DEBUG_PRINTM(zf);
-            cv::Mat response;
-            if (m_use_linearkernel)
-                response = fft.inverse((p_model_alphaf * zf).sum_over_channels());
-            else {
-                ComplexMat kzf = gaussian_correlation(zf, p_model_xf, p_kernel_sigma);
-                DEBUG_PRINTM(p_model_alphaf);
-                DEBUG_PRINTM(kzf);
-                DEBUG_PRINTM(p_model_alphaf * kzf);
-                response = fft.inverse(p_model_alphaf * kzf);
-            }
-            DEBUG_PRINTM(response);
-
-            /* target location is at the maximum response. we must take into
-               account the fact that, if the target doesn't move, the peak
-               will appear at the top-left corner, not at the center (this is
-               discussed in the paper). the responses wrap around cyclically. */
-            double min_val, max_val;
-            cv::Point2i min_loc, max_loc;
-            cv::minMaxLoc(response, &min_val, &max_val, &min_loc, &max_loc);
-            DEBUG_PRINT(max_loc);
-
-            double weight = p_scales[i] < 1. ? p_scales[i] : 1./p_scales[i];
+#pragma omp parallel for schedule(dynamic)
+        for (size_t i = 0; i < scale_vars.size(); ++i) {
+            scale_track(this->scale_vars[i], input_rgb, input_gray, this->p_scales[i]);
 #pragma omp critical
             {
-                if (max_val*weight > max_response) {
-                    max_response = max_val*weight;
-                    max_response_map = response;
-                    max_response_pt = max_loc;
+                if (this->scale_vars[i].max_response > max_response) {
+                    max_response = this->scale_vars[i].max_response;
+                    max_response_pt = & this->scale_vars[i].max_loc;
+                    max_response_map = & this->scale_vars[i].response;
                     scale_index = i;
                 }
             }
-#pragma omp ordered
-            scale_responses.push_back(max_val*weight);
         }
     }
-    DEBUG_PRINTM(max_response_map);
-    DEBUG_PRINT(max_response_pt);
+
+    DEBUG_PRINTM(*max_response_map);
+    DEBUG_PRINT(*max_response_pt);
+
     //sub pixel quadratic interpolation from neighbours
-    if (max_response_pt.y > max_response_map.rows / 2) //wrap around to negative half-space of vertical axis
-        max_response_pt.y = max_response_pt.y - max_response_map.rows;
-    if (max_response_pt.x > max_response_map.cols / 2) //same for horizontal axis
-        max_response_pt.x = max_response_pt.x - max_response_map.cols;
+    if (max_response_pt->y > max_response_map->rows / 2) //wrap around to negative half-space of vertical axis
+        max_response_pt->y = max_response_pt->y - max_response_map->rows;
+    if (max_response_pt->x > max_response_map->cols / 2) //same for horizontal axis
+        max_response_pt->x = max_response_pt->x - max_response_map->cols;
 
-    cv::Point2f new_location(max_response_pt.x, max_response_pt.y);
+    cv::Point2f new_location(max_response_pt->x, max_response_pt->y);
     DEBUG_PRINT(new_location);
 
     if (m_use_subpixel_localization)
-        new_location = sub_pixel_peak(max_response_pt, max_response_map);
+        new_location = sub_pixel_peak(*max_response_pt, *max_response_map);
     DEBUG_PRINT(new_location);
 
     p_pose.cx += p_current_scale*p_cell_size*new_location.x;
@@ -431,7 +440,7 @@ void KCF_Tracker::track(cv::Mat &img)
     //sub grid scale interpolation
     double new_scale = p_scales[scale_index];
     if (m_use_subgrid_scale)
-        new_scale = sub_grid_scale(scale_responses, scale_index);
+        new_scale = sub_grid_scale(scale_index);
 
     p_current_scale *= new_scale;
 
@@ -440,25 +449,27 @@ void KCF_Tracker::track(cv::Mat &img)
     if (p_current_scale > p_min_max_scale[1])
         p_current_scale = p_min_max_scale[1];
     //obtain a subwindow for training at newly estimated target position
-    patch_feat = get_features(input_rgb, input_gray, p_pose.cx, p_pose.cy, p_windows_size[0], p_windows_size[1], p_current_scale);
-    ComplexMat xf = fft.forward_window(patch_feat);
+    get_features(input_rgb, input_gray, p_pose.cx, p_pose.cy, p_windows_size[0], p_windows_size[1], scale_vars[0], p_current_scale);
+    scale_vars[0].flag = Tracker_flags::TRACKER_UPDATE;
+    fft.forward_window(scale_vars[0]);
 
     //subsequent frames, interpolate model
-    p_model_xf = p_model_xf * (1. - p_interp_factor) + xf * p_interp_factor;
+    p_model_xf = p_model_xf * (1. - p_interp_factor) + scale_vars[0].xf * p_interp_factor;
 
     ComplexMat alphaf_num, alphaf_den;
 
     if (m_use_linearkernel) {
-        ComplexMat xfconj = xf.conj();
+        ComplexMat xfconj = scale_vars[0].xf.conj();
         alphaf_num = xfconj.mul(p_yf);
-        alphaf_den = (xf * xfconj);
+        alphaf_den = (scale_vars[0].xf * xfconj);
     } else {
+        scale_vars[0].flag = Tracker_flags::AUTO_CORRELATION;
         //Kernel Ridge Regression, calculate alphas (in Fourier domain)
-        ComplexMat kf = gaussian_correlation(xf, xf, p_kernel_sigma, true);
+        gaussian_correlation(scale_vars[0], scale_vars[0].xf, scale_vars[0].xf, p_kernel_sigma, true);
 //        ComplexMat alphaf = p_yf / (kf + p_lambda); //equation for fast training
 //        p_model_alphaf = p_model_alphaf * (1. - p_interp_factor) + alphaf * p_interp_factor;
-        alphaf_num = p_yf * kf;
-        alphaf_den = kf * (kf + p_lambda);
+        alphaf_num = p_yf * scale_vars[0].kf;
+        alphaf_den = scale_vars[0].kf * (scale_vars[0].kf + p_lambda);
     }
 
     p_model_alphaf_num = p_model_alphaf_num * (1. - p_interp_factor) + alphaf_num * p_interp_factor;
@@ -466,9 +477,50 @@ void KCF_Tracker::track(cv::Mat &img)
     p_model_alphaf = p_model_alphaf_num / p_model_alphaf_den;
 }
 
+void KCF_Tracker::scale_track(Scale_vars & vars, cv::Mat & input_rgb, cv::Mat & input_gray, double scale)
+{
+    get_features(input_rgb, input_gray, this->p_pose.cx, this->p_pose.cy, this->p_windows_size[0], this->p_windows_size[1],
+                                vars, this->p_current_scale * scale);
+
+    vars.flag = Tracker_flags::SCALE_RESPONSE;
+    fft.forward_window(vars);
+    DEBUG_PRINTM(vars.zf);
+
+    if (m_use_linearkernel) {
+                vars.kzf = (vars.zf.mul2(this->p_model_alphaf)).sum_over_channels();
+                vars.flag = Tracker_flags::RESPONSE;
+                fft.inverse(vars);
+    } else {
+        vars.flag = Tracker_flags::CROSS_CORRELATION;
+        gaussian_correlation(vars, vars.zf, this->p_model_xf, this->p_kernel_sigma);
+        DEBUG_PRINTM(this->p_model_alphaf);
+        DEBUG_PRINTM(vars.kzf);
+        DEBUG_PRINTM(this->p_model_alphaf * vars.kzf);
+        vars.flag = Tracker_flags::RESPONSE;
+        vars.kzf = this->p_model_alphaf * vars.kzf;
+        //TODO Add support for fft.inverse(vars) for CUFFT
+        fft.inverse(vars);
+    }
+
+    DEBUG_PRINTM(vars.response);
+
+    /* target location is at the maximum response. we must take into
+    account the fact that, if the target doesn't move, the peak
+    will appear at the top-left corner, not at the center (this is
+    discussed in the paper). the responses wrap around cyclically. */
+    double min_val;
+    cv::Point2i min_loc;
+    cv::minMaxLoc(vars.response, &min_val, &vars.max_val, &min_loc, &vars.max_loc);
+
+    DEBUG_PRINT(vars.max_loc);
+
+    double weight = scale < 1. ? scale : 1./scale;
+    vars.max_response = vars.max_val*weight;
+}
+
 // ****************************************************************************
 
-std::vector<cv::Mat> KCF_Tracker::get_features(cv::Mat & input_rgb, cv::Mat & input_gray, int cx, int cy, int size_x, int size_y, double scale)
+void KCF_Tracker::get_features(cv::Mat & input_rgb, cv::Mat & input_gray, int cx, int cy, int size_x, int size_y, Scale_vars &vars, double scale)
 {
     int size_x_scaled = floor(size_x*scale);
     int size_y_scaled = floor(size_y*scale);
@@ -485,7 +537,7 @@ std::vector<cv::Mat> KCF_Tracker::get_features(cv::Mat & input_rgb, cv::Mat & in
     }
 
     // get hog(Histogram of Oriented Gradients) features
-    std::vector<cv::Mat> hog_feat = FHoG::extract(patch_gray, 2, p_cell_size, 9);
+    FHoG::extract(patch_gray, vars, 2, p_cell_size, 9);
 
     //get color rgb features (simple r,g,b channels)
     std::vector<cv::Mat> color_feat;
@@ -516,11 +568,11 @@ std::vector<cv::Mat> KCF_Tracker::get_features(cv::Mat & input_rgb, cv::Mat & in
         color_feat.insert(color_feat.end(), cn_feat.begin(), cn_feat.end());
     }
 
-    hog_feat.insert(hog_feat.end(), color_feat.begin(), color_feat.end());
-    return hog_feat;
+    vars.patch_feats.insert(vars.patch_feats.end(), color_feat.begin(), color_feat.end());
+    return;
 }
 
-cv::Mat KCF_Tracker::gaussian_shaped_labels(double sigma, int dim1, int dim2)
+void KCF_Tracker::gaussian_shaped_labels(Scale_vars & vars, double sigma, int dim1, int dim2)
 {
     cv::Mat labels(dim2, dim1, CV_32FC1);
     int range_y[2] = {-dim2 / 2, dim2 - dim2 / 2};
@@ -537,11 +589,12 @@ cv::Mat KCF_Tracker::gaussian_shaped_labels(double sigma, int dim1, int dim2)
     }
 
     //rotate so that 1 is at top-left corner (see KCF paper for explanation)
-    cv::Mat rot_labels = circshift(labels, range_x[0], range_y[0]);
+    cv::Mat tmp = circshift(labels, range_x[0], range_y[0]);
+    tmp.copyTo(vars.rot_labels);
     //sanity check, 1 at top left corner
-    assert(rot_labels.at<float>(0,0) >= 1.f - 1e-10f);
+    assert(vars.rot_labels.at<float>(0,0) >= 1.f - 1e-10f);
 
-    return rot_labels;
+    return;
 }
 
 cv::Mat KCF_Tracker::circshift(const cv::Mat &patch, int x_rot, int y_rot)
@@ -625,7 +678,7 @@ cv::Mat KCF_Tracker::cosine_window_function(int dim1, int dim2)
 // Returns sub-window of image input centered at [cx, cy] coordinates),
 // with size [width, height]. If any pixels are outside of the image,
 // they will replicate the values at the borders.
-cv::Mat KCF_Tracker::get_subwindow(const cv::Mat &input, int cx, int cy, int width, int height)
+cv::Mat KCF_Tracker::get_subwindow(const cv::Mat & input, int cx, int cy, int width, int height)
 {
     cv::Mat patch;
 
@@ -679,46 +732,45 @@ cv::Mat KCF_Tracker::get_subwindow(const cv::Mat &input, int cx, int cy, int wid
     return patch;
 }
 
-ComplexMat KCF_Tracker::gaussian_correlation(const ComplexMat &xf, const ComplexMat &yf, double sigma, bool auto_correlation)
+void KCF_Tracker::gaussian_correlation(struct Scale_vars & vars, const ComplexMat & xf, const ComplexMat & yf, double sigma, bool auto_correlation)
 {
 #ifdef CUFFT
-    xf.sqr_norm(xf_sqr_norm_d);
+    xf.sqr_norm(vars.xf_sqr_norm_d);
     if (!auto_correlation)
-        yf.sqr_norm(yf_sqr_norm_d);
+        yf.sqr_norm(vars.yf_sqr_norm_d);
 #else
-    xf.sqr_norm(xf_sqr_norm);
+    xf.sqr_norm(vars.xf_sqr_norm);
     if (auto_correlation){
-      yf_sqr_norm[0] = xf_sqr_norm[0];
+      vars.yf_sqr_norm[0] = vars.xf_sqr_norm[0];
     } else {
-       yf.sqr_norm(yf_sqr_norm);
+       yf.sqr_norm(vars.yf_sqr_norm);
     }
 #endif
-    ComplexMat xyf;
-    xyf = auto_correlation ? xf.sqr_mag() : xf.mul2(yf.conj());
-    DEBUG_PRINTM(xyf);
+    vars.xyf = auto_correlation ? xf.sqr_mag() : xf.mul2(yf.conj());
+    DEBUG_PRINTM(vars.xyf);
 #ifdef CUFFT
+    fft.inverse(vars);
     if(auto_correlation)
-        cuda_gaussian_correlation(fft.inverse_raw(xyf), gauss_corr_res, xf_sqr_norm_d, xf_sqr_norm_d, sigma, xf.n_channels, xf.n_scales, p_roi_height, p_roi_width);
+        cuda_gaussian_correlation(vars.data_i_features, vars.gauss_corr_res, vars.xf_sqr_norm_d, vars.xf_sqr_norm_d, sigma, xf.n_channels, xf.n_scales, p_roi_height, p_roi_width);
     else
-        cuda_gaussian_correlation(fft.inverse_raw(xyf), gauss_corr_res, xf_sqr_norm_d, yf_sqr_norm_d, sigma, xf.n_channels, xf.n_scales, p_roi_height, p_roi_width);
-
-    return fft.forward_raw(gauss_corr_res, xf.n_scales==p_num_scales);
+        cuda_gaussian_correlation(vars.data_i_features, vars.gauss_corr_res, vars.xf_sqr_norm_d, vars.yf_sqr_norm_d, sigma, xf.n_channels, xf.n_scales, p_roi_height, p_roi_width);
 #else
     //ifft2 and sum over 3rd dimension, we dont care about individual channels
-    cv::Mat ifft2_res = fft.inverse(xyf);
-    DEBUG_PRINTM(ifft2_res);
+    fft.inverse(vars);
+    DEBUG_PRINTM(vars.ifft2_res);
     cv::Mat xy_sum;
     if (xf.channels() != p_num_scales*p_num_of_feats)
-        xy_sum.create(ifft2_res.size(), CV_32FC1);
+        xy_sum.create(vars.ifft2_res.size(), CV_32FC1);
     else
-        xy_sum.create(ifft2_res.size(), CV_32FC(p_scales.size()));
+        xy_sum.create(vars.ifft2_res.size(), CV_32FC(p_scales.size()));
     xy_sum.setTo(0);
-    for (int y = 0; y < ifft2_res.rows; ++y) {
-        float * row_ptr = ifft2_res.ptr<float>(y);
+    for (int y = 0; y < vars.ifft2_res.rows; ++y) {
+        float * row_ptr = vars.ifft2_res.ptr<float>(y);
         float * row_ptr_sum = xy_sum.ptr<float>(y);
-        for (int x = 0; x < ifft2_res.cols; ++x) {
+        for (int x = 0; x < vars.ifft2_res.cols; ++x) {
             for (int sum_ch = 0; sum_ch < xy_sum.channels(); ++sum_ch) {
-                row_ptr_sum[(x*xy_sum.channels())+sum_ch] += std::accumulate(row_ptr + x*ifft2_res.channels() + sum_ch*(ifft2_res.channels()/xy_sum.channels()), (row_ptr + x*ifft2_res.channels() + (sum_ch+1)*(ifft2_res.channels()/xy_sum.channels())), 0.f);
+                row_ptr_sum[(x*xy_sum.channels())+sum_ch] += std::accumulate(row_ptr + x*vars.ifft2_res.channels() + sum_ch*(vars.ifft2_res.channels()/xy_sum.channels()),
+                                                                                                                                                        (row_ptr + x*vars.ifft2_res.channels() + (sum_ch+1)*(vars.ifft2_res.channels()/xy_sum.channels())), 0.f);
             }
         }
     }
@@ -726,18 +778,17 @@ ComplexMat KCF_Tracker::gaussian_correlation(const ComplexMat &xf, const Complex
 
     std::vector<cv::Mat> scales;
     cv::split(xy_sum,scales);
-    cv::Mat in_all(scales[0].rows * xf.n_scales, scales[0].cols, CV_32F);
 
     float numel_xf_inv = 1.f/(xf.cols * xf.rows * (xf.channels()/xf.n_scales));
     for (int i = 0; i < xf.n_scales; ++i){
-        cv::Mat in_roi(in_all, cv::Rect(0, i*scales[0].rows, scales[0].cols, scales[0].rows));
-        cv::exp(- 1.f / (sigma * sigma) * cv::max((xf_sqr_norm[i] + yf_sqr_norm[0] - 2 * scales[i]) * numel_xf_inv, 0), in_roi);
+        cv::Mat in_roi(vars.in_all, cv::Rect(0, i*scales[0].rows, scales[0].cols, scales[0].rows));
+        cv::exp(- 1.f / (sigma * sigma) * cv::max((vars.xf_sqr_norm[i] + vars.yf_sqr_norm[0] - 2 * scales[i]) * numel_xf_inv, 0), in_roi);
         DEBUG_PRINTM(in_roi);
     }
-
-    DEBUG_PRINTM(in_all);
-    return fft.forward(in_all);
 #endif
+    DEBUG_PRINTM(vars.in_all);
+    fft.forward(vars);
+    return;
 }
 
 float get_response_circular(cv::Point2i & pt, cv::Mat & response)
@@ -766,6 +817,7 @@ cv::Point2f KCF_Tracker::sub_pixel_peak(cv::Point & max_loc, cv::Mat & response)
     cv::Point2i p4(max_loc.x-1, max_loc.y), p5(max_loc.x+1, max_loc.y);
     cv::Point2i p6(max_loc.x-1, max_loc.y+1), p7(max_loc.x, max_loc.y+1), p8(max_loc.x+1, max_loc.y+1);
 
+    // clang-format off
     // fit 2d quadratic function f(x, y) = a*x^2 + b*x*y + c*y^2 + d*x + e*y + f
     cv::Mat A = (cv::Mat_<float>(9, 6) <<
                  p1.x*p1.x, p1.x*p1.y, p1.y*p1.y, p1.x, p1.y, 1.f,
@@ -787,6 +839,7 @@ cv::Point2f KCF_Tracker::sub_pixel_peak(cv::Point & max_loc, cv::Mat & response)
                     get_response_circular(p7, response),
                     get_response_circular(p8, response),
                     get_response_circular(max_loc, response));
+    // clang-format on
     cv::Mat x;
     cv::solve(A, fval, x, cv::DECOMP_SVD);
 
@@ -802,7 +855,7 @@ cv::Point2f KCF_Tracker::sub_pixel_peak(cv::Point & max_loc, cv::Mat & response)
     return sub_peak;
 }
 
-double KCF_Tracker::sub_grid_scale(std::vector<double> & responses, int index)
+double KCF_Tracker::sub_grid_scale(int index)
 {
     cv::Mat A, fval;
     if (index < 0 || index > (int)p_scales.size()-1) {
@@ -814,7 +867,7 @@ double KCF_Tracker::sub_grid_scale(std::vector<double> & responses, int index)
             A.at<float>(i, 0) = p_scales[i] * p_scales[i];
             A.at<float>(i, 1) = p_scales[i];
             A.at<float>(i, 2) = 1;
-            fval.at<float>(i) = responses[i];
+            fval.at<float>(i) = scale_vars[i].max_response;
         }
     } else {
         //only from neighbours
@@ -825,7 +878,7 @@ double KCF_Tracker::sub_grid_scale(std::vector<double> & responses, int index)
              p_scales[index-1] * p_scales[index-1], p_scales[index-1], 1,
              p_scales[index] * p_scales[index], p_scales[index], 1,
              p_scales[index+1] * p_scales[index+1], p_scales[index+1], 1);
-        fval = (cv::Mat_<float>(3, 1) << responses[index-1], responses[index], responses[index+1]);
+        fval = (cv::Mat_<float>(3, 1) << scale_vars[index-1].max_response, scale_vars[index].max_response, scale_vars[index+1].max_response);
     }
 
     cv::Mat x;