From 0842e09570cfa8107cdbbd65eaaa383248d8f651 Mon Sep 17 00:00:00 2001
From: Nissim Hadar <nissim.hadar@gmail.com>
Date: Thu, 30 Nov 2017 13:59:02 -0800
Subject: [PATCH] Debugging the image comparison.

---
 tools/auto-tester/src/ImageComparer.cpp    | 35 +++++++++++-----------
 tools/auto-tester/src/Test.cpp             |  2 +-
 tools/auto-tester/src/ui/MismatchWindow.ui |  6 ++--
 3 files changed, 21 insertions(+), 22 deletions(-)

diff --git a/tools/auto-tester/src/ImageComparer.cpp b/tools/auto-tester/src/ImageComparer.cpp
index 9151255d96..12ef20010c 100644
--- a/tools/auto-tester/src/ImageComparer.cpp
+++ b/tools/auto-tester/src/ImageComparer.cpp
@@ -26,9 +26,9 @@ double ImageComparer::compareImages(QImage resultImage, QImage expectedImage) co
     const double c2 = (K2 * L) * (K2 * L);
 
     // Coefficients for luminosity calculation
-    const double RED_COEFFICIENT = 0.212655;
-    const double GREEN_COEFFICIENT = 0.715158;
-    const double BLUE_COEFFICIENT = 0.072187;
+    const double R_Y = 0.212655f;
+    const double G_Y = 0.715158f;
+    const double B_Y = 0.072187f;
 
     // First go over all full 8x8 blocks
     // This is done in 3 loops
@@ -42,7 +42,11 @@ double ImageComparer::compareImages(QImage resultImage, QImage expectedImage) co
     const int WIN_SIZE = 8;
     int x{ 0 };             // column index (start of block)
     int y{ 0 };             // row index (start of block
-    double ssimMax{ 0.0 };
+    double ssimMin{ 1.0 };
+    
+    // Pixels are processed in sqare blocks
+    double p[WIN_SIZE * WIN_SIZE];
+    double q[WIN_SIZE * WIN_SIZE];
 
     while (x < expectedImage.width()) {
         int lastX = x + WIN_SIZE;
@@ -56,22 +60,17 @@ double ImageComparer::compareImages(QImage resultImage, QImage expectedImage) co
                 y -= (lastY - expectedImage.height());
             }
 
-            // Collect pixels
+            // Collect pixels into linear arrays
             int i{ 0 };
-            double p[WIN_SIZE * WIN_SIZE];
-            double q[WIN_SIZE * WIN_SIZE];
             for (int xx = 0; xx < WIN_SIZE; ++xx) {
                 for (int yy = 0; yy < WIN_SIZE; ++yy) {
                     // Get pixels
-                    QRgb pixelP = expectedImage.pixel(QPoint(xx, yy));
-                    QRgb pixelQ = resultImage.pixel(QPoint(xx, yy));
+                    QRgb pixelP = expectedImage.pixel(QPoint(x + xx, y + yy));
+                    QRgb pixelQ = resultImage.pixel(QPoint(x + xx, y + yy));
 
-                    // Convert to vec3
-                    p[i] = 
-                        RED_COEFFICIENT * qRed(pixelP) + GREEN_COEFFICIENT * qGreen(pixelP) + BLUE_COEFFICIENT * qBlue(pixelP);
-
-                    q[i] = 
-                        RED_COEFFICIENT * qRed(pixelQ) + GREEN_COEFFICIENT * qGreen(pixelQ) + BLUE_COEFFICIENT * qBlue(pixelQ);
+                    // Convert to luminence
+                    p[i] = R_Y * qRed(pixelP) + G_Y * qGreen(pixelP) + B_Y * qBlue(pixelP);
+                    q[i] = R_Y * qRed(pixelQ) + G_Y * qGreen(pixelQ) + B_Y * qBlue(pixelQ);
 
                     ++i;
                 }
@@ -106,8 +105,8 @@ double ImageComparer::compareImages(QImage resultImage, QImage expectedImage) co
 
             double ssim = numerator / denominator;
 
-            if (ssim > ssimMax) {
-                ssimMax = ssim;
+            if (ssim < ssimMin) {
+                ssimMin = ssim;
             }
 
             y += WIN_SIZE;
@@ -115,5 +114,5 @@ double ImageComparer::compareImages(QImage resultImage, QImage expectedImage) co
         x += WIN_SIZE;
     }
 
-    return ssimMax;
+    return ssimMin;
 };
diff --git a/tools/auto-tester/src/Test.cpp b/tools/auto-tester/src/Test.cpp
index ae5fd33dd5..5515c0b8dd 100644
--- a/tools/auto-tester/src/Test.cpp
+++ b/tools/auto-tester/src/Test.cpp
@@ -24,7 +24,7 @@ Test::Test() {
 bool Test::compareImageLists(QStringList expectedImages, QStringList resultImages) {
     // Loop over both lists and compare each pair of images
     // Quit loop if user has aborted due to a failed test.
-    const double THRESHOLD{ 0.99999 };
+    const double THRESHOLD{ 0.98 };
     bool success{ true };
     bool keepOn{ true };
     for (int i = 0; keepOn && i < expectedImages.length(); ++i) {
diff --git a/tools/auto-tester/src/ui/MismatchWindow.ui b/tools/auto-tester/src/ui/MismatchWindow.ui
index ab3a8d57c8..cab6c61e1c 100644
--- a/tools/auto-tester/src/ui/MismatchWindow.ui
+++ b/tools/auto-tester/src/ui/MismatchWindow.ui
@@ -135,9 +135,9 @@
   <widget class="QLabel" name="errorLabel">
    <property name="geometry">
     <rect>
-     <x>960</x>
+     <x>810</x>
      <y>600</y>
-     <width>181</width>
+     <width>720</width>
      <height>28</height>
     </rect>
    </property>
@@ -147,7 +147,7 @@
     </font>
    </property>
    <property name="text">
-    <string>error</string>
+    <string>similarity</string>
    </property>
   </widget>
  </widget>