libwebp: update to 0.5.0

third_party/libwebp/enc/picture_psnr.c

 // Copyright 2014 Google Inc. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the COPYING file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS. All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
 // WebPPicture tools for measuring distortion
 //
 // Author: Skal (pascal.massimino@gmail.com)
 
 #include <math.h>
+#include <stdlib.h>
 
 #include "./vp8enci.h"
+#include "../utils/utils.h"
 
 //------------------------------------------------------------------------------
 // local-min distortion
 //
 // For every pixel in the *reference* picture, we search for the local best
 // match in the compressed image. This is not a symmetrical measure.
 
 #define RADIUS 2  // search radius. Shouldn't be too large.
 
-static float AccumulateLSIM(const uint8_t* src, int src_stride,
-                            const uint8_t* ref, int ref_stride,
-                            int w, int h) {
+static void AccumulateLSIM(const uint8_t* src, int src_stride,
+                           const uint8_t* ref, int ref_stride,
+                           int w, int h, DistoStats* stats) {
   int x, y;
   double total_sse = 0.;
   for (y = 0; y < h; ++y) {
     const int y_0 = (y - RADIUS < 0) ? 0 : y - RADIUS;
     const int y_1 = (y + RADIUS + 1 >= h) ? h : y + RADIUS + 1;
     for (x = 0; x < w; ++x) {
       const int x_0 = (x - RADIUS < 0) ? 0 : x - RADIUS;
       const int x_1 = (x + RADIUS + 1 >= w) ? w : x + RADIUS + 1;
       double best_sse = 255. * 255.;
       const double value = (double)ref[y * ref_stride + x];
       int i, j;
       for (j = y_0; j < y_1; ++j) {
-        const uint8_t* s = src + j * src_stride;
+        const uint8_t* const s = src + j * src_stride;
         for (i = x_0; i < x_1; ++i) {
-          const double sse = (double)(s[i] - value) * (s[i] - value);
+          const double diff = s[i] - value;
+          const double sse = diff * diff;
           if (sse < best_sse) best_sse = sse;
         }
       }
       total_sse += best_sse;
     }
   }
-  return (float)total_sse;
+  stats->w = w * h;
+  stats->xm = 0;
+  stats->ym = 0;
+  stats->xxm = total_sse;
+  stats->yym = 0;
+  stats->xxm = 0;
 }
 #undef RADIUS
 
 //------------------------------------------------------------------------------
 // Distortion
 
 // Max value returned in case of exact similarity.
 static const double kMinDistortion_dB = 99.;
 static float GetPSNR(const double v) {
   return (float)((v > 0.) ? -4.3429448 * log(v / (255 * 255.))
                           : kMinDistortion_dB);
 }
 
 int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref,
                           int type, float result[5]) {
   DistoStats stats[5];
-  int has_alpha;
-  int uv_w, uv_h;
+  int w, h;
+
+  memset(stats, 0, sizeof(stats));
 
   if (src == NULL || ref == NULL ||
       src->width != ref->width || src->height != ref->height ||
-      src->y == NULL || ref->y == NULL ||
-      src->u == NULL || ref->u == NULL ||
-      src->v == NULL || ref->v == NULL ||
-      result == NULL) {
+      src->use_argb != ref->use_argb || result == NULL) {
     return 0;
   }
-  // TODO(skal): provide distortion for ARGB too.
-  if (src->use_argb == 1 || src->use_argb != ref->use_argb) {
-    return 0;
-  }
+  w = src->width;
+  h = src->height;
 
-  has_alpha = !!(src->colorspace & WEBP_CSP_ALPHA_BIT);
-  if (has_alpha != !!(ref->colorspace & WEBP_CSP_ALPHA_BIT) ||
-      (has_alpha && (src->a == NULL || ref->a == NULL))) {
-    return 0;
-  }
-
-  memset(stats, 0, sizeof(stats));
-
-  uv_w = (src->width + 1) >> 1;
-  uv_h = (src->height + 1) >> 1;
-  if (type >= 2) {
-    float sse[4];
-    sse[0] = AccumulateLSIM(src->y, src->y_stride,
-                            ref->y, ref->y_stride, src->width, src->height);
-    sse[1] = AccumulateLSIM(src->u, src->uv_stride,
-                            ref->u, ref->uv_stride, uv_w, uv_h);
-    sse[2] = AccumulateLSIM(src->v, src->uv_stride,
-                            ref->v, ref->uv_stride, uv_w, uv_h);
-    sse[3] = has_alpha ? AccumulateLSIM(src->a, src->a_stride,
-                                        ref->a, ref->a_stride,
-                                        src->width, src->height)
-                       : 0.f;
-    result[0] = GetPSNR(sse[0] / (src->width * src->height));
-    result[1] = GetPSNR(sse[1] / (uv_w * uv_h));
-    result[2] = GetPSNR(sse[2] / (uv_w * uv_h));
-    result[3] = GetPSNR(sse[3] / (src->width * src->height));
-    {
-      double total_sse = sse[0] + sse[1] + sse[2];
-      int total_pixels = src->width * src->height + 2 * uv_w * uv_h;
-      if (has_alpha) {
-        total_pixels += src->width * src->height;
-        total_sse += sse[3];
+  if (src->use_argb == 1) {
+    if (src->argb == NULL || ref->argb == NULL) {
+      return 0;
+    } else {
+      int i, j, c;
+      uint8_t* tmp1, *tmp2;
+      uint8_t* const tmp_plane =
+          (uint8_t*)WebPSafeMalloc(2ULL * w * h, sizeof(*tmp_plane));
+      if (tmp_plane == NULL) return 0;
+      tmp1 = tmp_plane;
+      tmp2 = tmp_plane + w * h;
+      for (c = 0; c < 4; ++c) {
+        for (j = 0; j < h; ++j) {
+          for (i = 0; i < w; ++i) {
+            tmp1[j * w + i] = src->argb[i + j * src->argb_stride] >> (c * 8);
+            tmp2[j * w + i] = ref->argb[i + j * ref->argb_stride] >> (c * 8);
+          }
+        }
+        if (type >= 2) {
+          AccumulateLSIM(tmp1, w, tmp2, w, w, h, &stats[c]);
+        } else {
+          VP8SSIMAccumulatePlane(tmp1, w, tmp2, w, w, h, &stats[c]);
+        }
       }
-      result[4] = GetPSNR(total_sse / total_pixels);
+      free(tmp_plane);
     }
   } else {
+    int has_alpha, uv_w, uv_h;
+    if (src->y == NULL || ref->y == NULL ||
+        src->u == NULL || ref->u == NULL ||
+        src->v == NULL || ref->v == NULL) {
+      return 0;
+    }
+    has_alpha = !!(src->colorspace & WEBP_CSP_ALPHA_BIT);
+    if (has_alpha != !!(ref->colorspace & WEBP_CSP_ALPHA_BIT) ||
+        (has_alpha && (src->a == NULL || ref->a == NULL))) {
+      return 0;
+    }
+
+    uv_w = (src->width + 1) >> 1;
+    uv_h = (src->height + 1) >> 1;
+    if (type >= 2) {
+      AccumulateLSIM(src->y, src->y_stride, ref->y, ref->y_stride,
+                     w, h, &stats[0]);
+      AccumulateLSIM(src->u, src->uv_stride, ref->u, ref->uv_stride,
+                     uv_w, uv_h, &stats[1]);
+      AccumulateLSIM(src->v, src->uv_stride, ref->v, ref->uv_stride,
+                     uv_w, uv_h, &stats[2]);
+      if (has_alpha) {
+        AccumulateLSIM(src->a, src->a_stride, ref->a, ref->a_stride,
+                       w, h, &stats[3]);
+      }
+    } else {
+      VP8SSIMAccumulatePlane(src->y, src->y_stride,
+                             ref->y, ref->y_stride,
+                             w, h, &stats[0]);
+      VP8SSIMAccumulatePlane(src->u, src->uv_stride,
+                             ref->u, ref->uv_stride,
+                             uv_w, uv_h, &stats[1]);
+      VP8SSIMAccumulatePlane(src->v, src->uv_stride,
+                             ref->v, ref->uv_stride,
+                             uv_w, uv_h, &stats[2]);
+      if (has_alpha) {
+        VP8SSIMAccumulatePlane(src->a, src->a_stride,
+                               ref->a, ref->a_stride,
+                               w, h, &stats[3]);
+      }
+    }
+  }
+  // Final stat calculations.
+  {
     int c;
-    VP8SSIMAccumulatePlane(src->y, src->y_stride,
-                           ref->y, ref->y_stride,
-                           src->width, src->height, &stats[0]);
-    VP8SSIMAccumulatePlane(src->u, src->uv_stride,
-                           ref->u, ref->uv_stride,
-                           uv_w, uv_h, &stats[1]);
-    VP8SSIMAccumulatePlane(src->v, src->uv_stride,
-                           ref->v, ref->uv_stride,
-                           uv_w, uv_h, &stats[2]);
-    if (has_alpha) {
-      VP8SSIMAccumulatePlane(src->a, src->a_stride,
-                             ref->a, ref->a_stride,
-                             src->width, src->height, &stats[3]);
-    }
     for (c = 0; c <= 4; ++c) {
       if (type == 1) {
         const double v = VP8SSIMGet(&stats[c]);
         result[c] = (float)((v < 1.) ? -10.0 * log10(1. - v)
                                      : kMinDistortion_dB);
       } else {
         const double v = VP8SSIMGetSquaredError(&stats[c]);
         result[c] = GetPSNR(v);
       }
       // Accumulate forward
       if (c < 4) VP8SSIMAddStats(&stats[c], &stats[4]);
     }
   }
   return 1;
 }
 
 //------------------------------------------------------------------------------