some tweaks to the colour propagation method for highlight recovery

with the attempt to make it "smoother" and more realistic (or at least eye
pleasing) in some corner cases

rtengine/hilite_recon.cc

@@ -28,6 +28,8 @@
 #include "rawimagesource.h"
 #include "rt_math.h"
 #include "opthelper.h"
+#include "gauss.h"
+
 namespace rtengine
 {
 
@@ -412,6 +414,9 @@ void RawImageSource :: HLRecovery_inpaint (float** red, float** green, float** b
     constexpr float itrans[ColorCount][ColorCount] =
     { { 1.f, 0.8660254f, -0.5f }, { 1.f, -0.8660254f, -0.5f }, { 1.f, 0.f, 1.f } };
 
+    std::unique_ptr<PixelsMap> recovered_partial;
+    std::unique_ptr<PixelsMap> recovered_full;
+
     if(settings->verbose)
         for(int c = 0; c < 3; c++) {
             printf("chmax[%d] : %f\tclmax[%d] : %f\tratio[%d] : %f\n", c, chmax[c], c, clmax[c], c, chmax[c] / clmax[c]);
@@ -566,7 +571,7 @@ void RawImageSource :: HLRecovery_inpaint (float** red, float** green, float** b
     //blur highlight data
     boxblur2(hilite_full[3], hilite_full4, temp, height, width, 1);
 
-    temp.free(); // free temporary buffer
+    //temp.free(); // free temporary buffer
 
     if(plistener) {
         progress += 0.05;
@@ -1104,29 +1109,39 @@ void RawImageSource :: HLRecovery_inpaint (float** red, float** green, float** b
             //now correct clipped channels
             if (pixel[0] > max_f[0] && pixel[1] > max_f[1] && pixel[2] > max_f[2]) {
                 //all channels clipped
-                float Y = (0.299 * clipfix[0] + 0.587 * clipfix[1] + 0.114 * clipfix[2]);
+                // float Y = (0.299 * clipfix[0] + 0.587 * clipfix[1] + 0.114 * clipfix[2]);
+                // float factor = whitept / Y;
+                // red[i][j]   = CLIP(clipfix[0] * factor);
+                // green[i][j] = CLIP(clipfix[1] * factor);
+                // blue[i][j]  = CLIP(clipfix[2] * factor);
+                red[i][j] = green[i][j] = blue[i][j] = whitept;
+                if (!recovered_full) {
+                    recovered_full.reset(new PixelsMap(width, height));
+                }
+                recovered_full->set(j, i);
                 
-                float factor = whitept / Y;
-                red[i][j]   = clipfix[0] * factor;
-                green[i][j] = clipfix[1] * factor;
-                blue[i][j]  = clipfix[2] * factor;
             } else {//some channels clipped
                 float notclipped[3] = {pixel[0] <= max_f[0] ? 1.f : 0.f, pixel[1] <= max_f[1] ? 1.f : 0.f, pixel[2] <= max_f[2] ? 1.f : 0.f};
 
                 if (notclipped[0] == 0.f) { //red clipped
-                    red[i][j]  = max(red[i][j], (clipfix[0] * ((notclipped[1] * pixel[1] + notclipped[2] * pixel[2]) /
+                    red[i][j]  = CLIP((clipfix[0] * ((notclipped[1] * pixel[1] + notclipped[2] * pixel[2]) /
                                                  (notclipped[1] * clipfix[1] + notclipped[2] * clipfix[2] + epsilon))));
                 }
 
                 if (notclipped[1] == 0.f) { //green clipped
-                    green[i][j] = max(green[i][j], (clipfix[1] * ((notclipped[2] * pixel[2] + notclipped[0] * pixel[0]) /
+                    green[i][j] = CLIP((clipfix[1] * ((notclipped[2] * pixel[2] + notclipped[0] * pixel[0]) /
                                                     (notclipped[2] * clipfix[2] + notclipped[0] * clipfix[0] + epsilon))));
                 }
 
                 if (notclipped[2] == 0.f) { //blue clipped
-                    blue[i][j]  = max(blue[i][j], (clipfix[2] * ((notclipped[0] * pixel[0] + notclipped[1] * pixel[1]) /
+                    blue[i][j]  = CLIP((clipfix[2] * ((notclipped[0] * pixel[0] + notclipped[1] * pixel[1]) /
                                                    (notclipped[0] * clipfix[0] + notclipped[1] * clipfix[1] + epsilon))));
                 }
+
+                if (!recovered_partial) {
+                    recovered_partial.reset(new PixelsMap(width, height));
+                }
+                recovered_partial->set(j, i);
            }
 
             Y = (0.299 * red[i][j] + 0.587 * green[i][j] + 0.114 * blue[i][j]);
@@ -1141,6 +1156,54 @@ void RawImageSource :: HLRecovery_inpaint (float** red, float** green, float** b
         }
     }
 
+    {
+        for (int c = 0; c < 3; ++c) {
+            float **color = c == 0 ? red : c == 1 ? green : blue;
+
+            if (recovered_partial) {
+#ifdef _OPENMP
+                #pragma omp parallel
+#endif
+                gaussianBlur(color, temp, width, height, 1.5f);
+
+#ifdef _OPENMP
+                #pragma omp parallel for
+#endif
+                for (int i = 0; i < height; ++i) {
+                    for (int j = 0; j < width; ++j) {
+                        int skip = recovered_partial->skipIfZero(j, i);
+                        if (skip) {
+                            j += skip-1;
+                        } else if (recovered_partial->get(j, i)) {
+                            color[i][j] = temp[i][j];
+                        }
+                    }
+                }
+            }
+
+            if (recovered_full) {
+#ifdef _OPENMP
+                #pragma omp parallel
+#endif
+                gaussianBlur(color, temp, width, height, 3.f);
+
+#ifdef _OPENMP
+                #pragma omp parallel for
+#endif
+                for (int i = 0; i < height; ++i) {
+                    for (int j = 0; j < width; ++j) {
+                        int skip = recovered_full->skipIfZero(j, i);
+                        if (skip) {
+                            j += skip-1;
+                        } else if (recovered_full->get(j, i)) {
+                            color[i][j] = temp[i][j];
+                        }
+                    }
+                }
+            }
+        }
+    }
+
     if(plistener) {
         plistener->setProgress(1.00);
     }