moved extension to the processing namespace and the processor accordingly into Processors namespace

src/ImageSharp/Processing/Normalization/HistogramEqualizationExtension.cs → src/ImageSharp/Processing/HistogramEqualizationExtension.cs

@@ -2,8 +2,9 @@
 // Licensed under the Apache License, Version 2.0.
 
 using SixLabors.ImageSharp.PixelFormats;
+using SixLabors.ImageSharp.Processing.Processors.Normalization;
 
-namespace SixLabors.ImageSharp.Processing.Normalization
+namespace SixLabors.ImageSharp.Processing
 {
     /// <summary>
     /// Adds extension that allows applying an HistogramEqualization to the image.
@@ -16,7 +17,7 @@ namespace SixLabors.ImageSharp.Processing.Normalization
         /// <typeparam name="TPixel">The pixel format.</typeparam>
         /// <param name="source">The image this method extends.</param>
         /// <param name="luminanceLevels">The number of different luminance levels. Typical values are 256 for 8-bit grayscale images
-        /// or 65536 for 16-bit grayscale images.Defaults to 65536.</param>
+        /// or 65536 for 16-bit grayscale images. Defaults to 65536.</param>
         /// <returns>A histogram equalized grayscale image.</returns>
         public static IImageProcessingContext<TPixel> HistogramEqualization<TPixel>(this IImageProcessingContext<TPixel> source, int luminanceLevels = 65536)
             where TPixel : struct, IPixel<TPixel>

src/ImageSharp/Processing/Normalization/HistogramEqualizationProcessor.cs → src/ImageSharp/Processing/Processors/Normalization/HistogramEqualizationProcessor.cs

@@ -5,11 +5,10 @@ using System;
 using System.Numerics;
 using SixLabors.ImageSharp.Advanced;
 using SixLabors.ImageSharp.PixelFormats;
-using SixLabors.ImageSharp.Processing.Processors;
 using SixLabors.Memory;
 using SixLabors.Primitives;
 
-namespace SixLabors.ImageSharp.Processing.Normalization
+namespace SixLabors.ImageSharp.Processing.Processors.Normalization
 {
     /// <summary>
     /// Applies a global histogram equalization to the image.
@@ -22,7 +21,7 @@ namespace SixLabors.ImageSharp.Processing.Normalization
         /// Initializes a new instance of the <see cref="HistogramEqualizationProcessor{TPixel}"/> class.
         /// </summary>
         /// <param name="luminanceLevels">The number of different luminance levels. Typical values are 256 for 8-bit grayscale images
-        /// or 65536 for 16-bit grayscale images.Defaults to 65536.</param>
+        /// or 65536 for 16-bit grayscale images. Defaults to 65536.</param>
         public HistogramEqualizationProcessor(int luminanceLevels = 65536)
         {
             Guard.MustBeGreaterThan(luminanceLevels, 0, nameof(luminanceLevels));
@@ -117,7 +116,7 @@ namespace SixLabors.ImageSharp.Processing.Normalization
         {
             // Convert to grayscale using ITU-R Recommendation BT.709
             var vector = sourcePixel.ToVector4();
-            int luminance = Convert.ToInt32(((.2126F * vector.X) + (.7152F * vector.Y) + (.0722F * vector.Y)) * luminanceLevels);
+            int luminance = Convert.ToInt32(((.2126F * vector.X) + (.7152F * vector.Y) + (.0722F * vector.Y)) * (luminanceLevels - 1));
 
             return luminance;
         }

tests/ImageSharp.Tests/Processing/Normalization/HistogramEqualizationTests.cs

@@ -3,7 +3,6 @@
 
 using SixLabors.ImageSharp.PixelFormats;
 using SixLabors.ImageSharp.Processing;
-using SixLabors.ImageSharp.Processing.Normalization;
 using Xunit;
 
 namespace SixLabors.ImageSharp.Tests.Processing.Normalization