intern/cycles/kernel/filter/filter_reconstruction.h

   1 /*
   2  * Copyright 2011-2017 Blender Foundation
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 CCL_NAMESPACE_BEGIN
  18
  19 ccl_device_inline void kernel_filter_construct_gramian(int x, int y,
  20                                                        int storage_stride,
  21                                                        int dx, int dy,
  22                                                        int w, int h,
  23                                                        int pass_stride,
  24                                                        const ccl_global float *ccl_restrict buffer,
  25                                                        ccl_global float *color_pass,
  26                                                        ccl_global float *variance_pass,
  27                                                        const ccl_global float *ccl_restrict transform,
  28                                                        ccl_global int *rank,
  29                                                        float weight,
  30                                                        ccl_global float *XtWX,
  31                                                        ccl_global float3 *XtWY,
  32                                                        int localIdx)
  33 {
  34         int p_offset =  y    *w +  x;
  35         int q_offset = (y+dy)*w + (x+dx);
  36
  37 #ifdef __KERNEL_CPU__
  38         const int stride = 1;
  39         (void)storage_stride;
  40         (void)localIdx;
  41         float design_row[DENOISE_FEATURES+1];
  42 #elif defined(__KERNEL_CUDA__)
  43         const int stride = storage_stride;
  44         ccl_local float shared_design_row[(DENOISE_FEATURES+1)*CCL_MAX_LOCAL_SIZE];
  45         ccl_local_param float *design_row = shared_design_row + localIdx*(DENOISE_FEATURES+1);
  46 #else
  47         const int stride = storage_stride;
  48         float design_row[DENOISE_FEATURES+1];
  49 #endif
  50
  51         float3 p_color = filter_get_pixel_color(color_pass + p_offset, pass_stride);
  52         float3 q_color = filter_get_pixel_color(color_pass + q_offset, pass_stride);
  53
  54         float p_std_dev = sqrtf(filter_get_pixel_variance(variance_pass + p_offset, pass_stride));
  55         float q_std_dev = sqrtf(filter_get_pixel_variance(variance_pass + q_offset, pass_stride));
  56
  57         /* If the pixel was flagged as an outlier during prefiltering, skip it.
  58          * Otherwise, perform the regular confidence interval test. */
  59         if(ccl_get_feature(buffer + q_offset, 0) < 0.0f ||
  60            average(fabs(p_color - q_color)) > 2.0f*(p_std_dev + q_std_dev + 1e-3f)) {
  61                 return;
  62         }
  63
  64         filter_get_design_row_transform(make_int2(x, y),       buffer + p_offset,
  65                                         make_int2(x+dx, y+dy), buffer + q_offset,
  66                                         pass_stride, *rank, design_row, transform, stride);
  67
  68         math_trimatrix_add_gramian_strided(XtWX, (*rank)+1, design_row, weight, stride);
  69         math_vec3_add_strided(XtWY, (*rank)+1, design_row, weight * q_color, stride);
  70 }
  71
  72 ccl_device_inline void kernel_filter_finalize(int x, int y, int w, int h,
  73                                               ccl_global float *buffer,
  74                                               ccl_global int *rank,
  75                                               int storage_stride,
  76                                               ccl_global float *XtWX,
  77                                               ccl_global float3 *XtWY,
  78                                               int4 buffer_params,
  79                                               int sample)
  80 {
  81 #ifdef __KERNEL_CPU__
  82         const int stride = 1;
  83         (void)storage_stride;
  84 #else
  85         const int stride = storage_stride;
  86 #endif
  87
  88         /* The weighted average of pixel colors (essentially, the NLM-filtered image).
  89          * In case the solution of the linear model fails due to numerical issues,
  90          * fall back to this value. */
  91         float3 mean_color = XtWY[0]/XtWX[0];
  92
  93         math_trimatrix_vec3_solve(XtWX, XtWY, (*rank)+1, stride);
  94
  95         float3 final_color = XtWY[0];
  96         if(!isfinite3_safe(final_color)) {
  97                 final_color = mean_color;
  98         }
  99
 100         ccl_global float *combined_buffer = buffer + (y*buffer_params.y + x + buffer_params.x)*buffer_params.z;
 101         final_color *= sample;
 102         if(buffer_params.w) {
 103                 final_color.x += combined_buffer[buffer_params.w+0];
 104                 final_color.y += combined_buffer[buffer_params.w+1];
 105                 final_color.z += combined_buffer[buffer_params.w+2];
 106         }
 107         combined_buffer[0] = final_color.x;
 108         combined_buffer[1] = final_color.y;
 109         combined_buffer[2] = final_color.z;
 110 }
 111
 112 #undef STORAGE_TYPE
 113
 114 CCL_NAMESPACE_END