From 44ff0bf5b006d560aed6ad9a71756005a93fbfe5 Mon Sep 17 00:00:00 2001
From: Darth Affe <darthaffe@wyrez.org>
Date: Sun, 21 Jul 2024 14:52:26 +0200
Subject: [PATCH] Improved accuracy of Average

---
 HPPH.Reference/PixelHelper.Average.cs | 40 +++++++++++++--------------
 HPPH/PixelHelper.Average.cs           | 14 +++++-----
 2 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/HPPH.Reference/PixelHelper.Average.cs b/HPPH.Reference/PixelHelper.Average.cs
index 2553764..c11a3ab 100644
--- a/HPPH.Reference/PixelHelper.Average.cs
+++ b/HPPH.Reference/PixelHelper.Average.cs
@@ -9,10 +9,10 @@ public static partial class ReferencePixelHelper
         float count = image.Width * image.Height;
 
         ISum sum = Sum(image);
-        return new ColorRGBA((byte)(sum.R / count),
-                             (byte)(sum.G / count),
-                             (byte)(sum.B / count),
-                             (byte)(sum.A / count));
+        return new ColorRGBA((byte)MathF.Round(sum.R / count),
+                             (byte)MathF.Round(sum.G / count),
+                             (byte)MathF.Round(sum.B / count),
+                             (byte)MathF.Round(sum.A / count));
     }
 
     public static T Average<T>(IImage<T> image)
@@ -21,10 +21,10 @@ public static partial class ReferencePixelHelper
         float count = image.Width * image.Height;
 
         ISum sum = Sum(image);
-        return (T)T.Create((byte)(sum.R / count),
-                           (byte)(sum.G / count),
-                           (byte)(sum.B / count),
-                           (byte)(sum.A / count));
+        return (T)T.Create((byte)MathF.Round(sum.R / count),
+                           (byte)MathF.Round(sum.G / count),
+                           (byte)MathF.Round(sum.B / count),
+                           (byte)MathF.Round(sum.A / count));
     }
 
     public static T Average<T>(RefImage<T> image)
@@ -33,10 +33,10 @@ public static partial class ReferencePixelHelper
         float count = image.Width * image.Height;
 
         ISum sum = Sum(image);
-        return (T)T.Create((byte)(sum.R / count),
-                           (byte)(sum.G / count),
-                           (byte)(sum.B / count),
-                           (byte)(sum.A / count));
+        return (T)T.Create((byte)MathF.Round(sum.R / count),
+                           (byte)MathF.Round(sum.G / count),
+                           (byte)MathF.Round(sum.B / count),
+                           (byte)MathF.Round(sum.A / count));
     }
 
     public static T Average<T>(Span<T> colors)
@@ -45,10 +45,10 @@ public static partial class ReferencePixelHelper
         float count = colors.Length;
 
         ISum sum = Sum(colors);
-        return (T)T.Create((byte)(sum.R / count),
-                           (byte)(sum.G / count),
-                           (byte)(sum.B / count),
-                           (byte)(sum.A / count));
+        return (T)T.Create((byte)MathF.Round(sum.R / count),
+                           (byte)MathF.Round(sum.G / count),
+                           (byte)MathF.Round(sum.B / count),
+                           (byte)MathF.Round(sum.A / count));
     }
 
     public static T Average<T>(ReadOnlySpan<T> colors)
@@ -57,10 +57,10 @@ public static partial class ReferencePixelHelper
         float count = colors.Length;
 
         ISum sum = Sum(colors);
-        return (T)T.Create((byte)(sum.R / count),
-                           (byte)(sum.G / count),
-                           (byte)(sum.B / count),
-                           (byte)(sum.A / count));
+        return (T)T.Create((byte)MathF.Round(sum.R / count),
+                           (byte)MathF.Round(sum.G / count),
+                           (byte)MathF.Round(sum.B / count),
+                           (byte)MathF.Round(sum.A / count));
     }
 
     #endregion
diff --git a/HPPH/PixelHelper.Average.cs b/HPPH/PixelHelper.Average.cs
index 054a519..b3744a2 100644
--- a/HPPH/PixelHelper.Average.cs
+++ b/HPPH/PixelHelper.Average.cs
@@ -82,9 +82,9 @@ public static partial class PixelHelper
         Generic4LongData sum = Sum(data);
 
         float count = data.Length;
-        return new Generic3ByteData((byte)(sum.L1 / count),
-                                    (byte)(sum.L2 / count),
-                                    (byte)(sum.L3 / count));
+        return new Generic3ByteData((byte)MathF.Round(sum.L1 / count),
+                                    (byte)MathF.Round(sum.L2 / count),
+                                    (byte)MathF.Round(sum.L3 / count));
     }
 
     private static Generic4ByteData Average(ReadOnlySpan<Generic4ByteData> data)
@@ -96,10 +96,10 @@ public static partial class PixelHelper
         Generic4LongData sum = Sum(data);
 
         float count = data.Length;
-        return new Generic4ByteData((byte)(sum.L1 / count),
-                                    (byte)(sum.L2 / count),
-                                    (byte)(sum.L3 / count),
-                                    (byte)(sum.L4 / count));
+        return new Generic4ByteData((byte)MathF.Round(sum.L1 / count),
+                                    (byte)MathF.Round(sum.L2 / count),
+                                    (byte)MathF.Round(sum.L3 / count),
+                                    (byte)MathF.Round(sum.L4 / count));
     }
 
     #endregion