1 files changed, 30 insertions, 0 deletions
diff --git a/test/util.h b/test/util.h
index 06a70cc8e..4d7f3d41e 100644
--- a/test/util.h
+++ b/test/util.h
@@ -11,8 +11,38 @@
 #ifndef TEST_UTIL_H_
 #define TEST_UTIL_H_
 
+#include <stdio.h>
+#include <math.h>
+#include "third_party/googletest/src/include/gtest/gtest.h"
+#include "vpx/vpx_image.h"
+
 // Macros
 #define PARAMS(...) ::testing::TestWithParam< std::tr1::tuple< __VA_ARGS__ > >
 #define GET_PARAM(k) std::tr1::get< k >(GetParam())
 
+static double compute_psnr(const vpx_image_t *img1,
+                           const vpx_image_t *img2) {
+  assert((img1->fmt == img2->fmt) &&
+         (img1->d_w == img2->d_w) &&
+         (img1->d_h == img2->d_h));
+
+  const unsigned int width_y  = img1->d_w;
+  const unsigned int height_y = img1->d_h;
+  unsigned int i, j;
+
+  int64_t sqrerr = 0;
+  for (i = 0; i < height_y; ++i)
+    for (j = 0; j < width_y; ++j) {
+      int64_t d = img1->planes[VPX_PLANE_Y][i * img1->stride[VPX_PLANE_Y] + j] -
+                  img2->planes[VPX_PLANE_Y][i * img2->stride[VPX_PLANE_Y] + j];
+      sqrerr += d * d;
+    }
+  double mse = static_cast<double>(sqrerr) / (width_y * height_y);
+  double psnr = 100.0;
+  if (mse > 0.0) {
+    psnr = 10 * log10(255.0 * 255.0 / mse);
+  }
+  return psnr;
+}
+
 #endif  // TEST_UTIL_H_