Update TPacked signature

Removes boxing allocation when comparing generic packed value.
9 years ago · 9afc73d2b4
152 changed files with 434 additions and 298 deletions
--- a/src/ImageSharp/Colors/PackedPixel/IPackedPixel.cs
+++ b/src/ImageSharp/Colors/PackedPixel/IPackedPixel.cs
@ -5,12 +5,13 @@

 namespace ImageSharp
 {
+    using System;
    /// <summary>
    /// An interface that represents a packed pixel type.
    /// </summary>
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public interface IPackedPixel<TPacked> : IPackedVector<TPacked>, IPackedBytes
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
    }
 }
--- a/src/ImageSharp/Colors/PackedPixel/IPackedVector.cs
+++ b/src/ImageSharp/Colors/PackedPixel/IPackedVector.cs
@ -5,6 +5,7 @@

 namespace ImageSharp
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -13,7 +14,7 @@ namespace ImageSharp
    /// </summary>
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public interface IPackedVector<TPacked> : IPackedVector
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Gets or sets the packed representation of the value.
--- a/src/ImageSharp/Common/Extensions/ArrayExtensions.cs
+++ b/src/ImageSharp/Common/Extensions/ArrayExtensions.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    /// <summary>
    /// Extension methods for arrays.
    /// </summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="PixelAccessor{TColor,TPacked}"/></returns>
        public static PixelAccessor<TColor, TPacked> Lock<TColor, TPacked>(this TColor[] pixels, int width, int height)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return new PixelAccessor<TColor, TPacked>(width, height, pixels);
        }
--- a/src/ImageSharp/Common/Helpers/ImageMaths.cs
+++ b/src/ImageSharp/Common/Helpers/ImageMaths.cs
@ -166,7 +166,7 @@ namespace ImageSharp
        /// </returns>
        public static Rectangle GetFilteredBoundingRectangle<TColor, TPacked>(ImageBase<TColor, TPacked> bitmap, float componentValue, RgbaComponent channel = RgbaComponent.B)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            const float Epsilon = .00001f;
            int width = bitmap.Width;
--- a/src/ImageSharp/Drawing/Brushes/Brushes`2.cs
+++ b/src/ImageSharp/Drawing/Brushes/Brushes`2.cs
@ -3,6 +3,8 @@
 // Licensed under the Apache License, Version 2.0.
 // </copyright>

+using System;
+
 namespace ImageSharp.Drawing.Brushes
 {
    /// <summary>
@ -13,7 +15,7 @@ namespace ImageSharp.Drawing.Brushes
    /// <returns>A Brush</returns>
    public class Brushes<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Percent10 Hatch Pattern
--- a/src/ImageSharp/Drawing/Brushes/IBrush.cs
+++ b/src/ImageSharp/Drawing/Brushes/IBrush.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Drawing
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -18,7 +20,7 @@ namespace ImageSharp.Drawing
    /// </remarks>
    public interface IBrush<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Creates the applicator for this brush.
--- a/src/ImageSharp/Drawing/Brushes/ImageBrush`2.cs
+++ b/src/ImageSharp/Drawing/Brushes/ImageBrush`2.cs
@ -17,7 +17,7 @@ namespace ImageSharp.Drawing.Brushes
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class ImageBrush<TColor, TPacked> : IBrush<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The image to paint.
--- a/src/ImageSharp/Drawing/Brushes/PatternBrush`2.cs
+++ b/src/ImageSharp/Drawing/Brushes/PatternBrush`2.cs
@ -8,6 +8,7 @@ namespace ImageSharp.Drawing.Brushes
    using System.Numerics;

    using Processors;
+    using System;

    /// <summary>
    /// Provides an implementation of a pattern brush for painting patterns.
@ -43,7 +44,7 @@ namespace ImageSharp.Drawing.Brushes
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class PatternBrush<TColor, TPacked> : IBrush<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The pattern.
--- a/src/ImageSharp/Drawing/Brushes/Processors/IBrushApplicator.cs
+++ b/src/ImageSharp/Drawing/Brushes/Processors/IBrushApplicator.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Drawing.Processors
    /// <seealso cref="System.IDisposable" />
    public interface IBrushApplicator<TColor, TPacked> : IDisposable // disposable will be required if/when there is an ImageBrush
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Gets the color for a single pixel.
--- a/src/ImageSharp/Drawing/Brushes/SolidBrush`2.cs
+++ b/src/ImageSharp/Drawing/Brushes/SolidBrush`2.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Drawing.Brushes
 {
+    using System;
    using System.Numerics;

    using Processors;
@ -16,7 +17,7 @@ namespace ImageSharp.Drawing.Brushes
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class SolidBrush<TColor, TPacked> : IBrush<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The color to paint.
--- a/src/ImageSharp/Drawing/Draw.cs
+++ b/src/ImageSharp/Drawing/Draw.cs
@ -5,6 +5,7 @@

 namespace ImageSharp
 {
+    using System;
    using System.Numerics;
    using Drawing;
    using Drawing.Brushes;
@ -32,7 +33,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, IShape shape, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(new DrawPathProcessor<TColor, TPacked>(pen, shape, options));
        }
@ -48,7 +49,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, IShape shape)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(pen, shape, GraphicsOptions.Default);
        }
@ -68,7 +69,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, IShape shape, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new Pen<TColor, TPacked>(brush, thickness), shape, options);
        }
@ -85,7 +86,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, IShape shape)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new Pen<TColor, TPacked>(brush, thickness), shape);
        }
@ -105,7 +106,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, IShape shape, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new SolidBrush<TColor, TPacked>(color), thickness, shape, options);
        }
@ -122,7 +123,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, IShape shape)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new SolidBrush<TColor, TPacked>(color), thickness, shape);
        }
@ -142,7 +143,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new Pen<TColor, TPacked>(brush, thickness), new Polygon(new LinearLineSegment(points)), options);
        }
@ -159,7 +160,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new Pen<TColor, TPacked>(brush, thickness), new Polygon(new LinearLineSegment(points)));
        }
@ -176,7 +177,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new SolidBrush<TColor, TPacked>(color), thickness, points);
        }
@ -196,7 +197,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(new SolidBrush<TColor, TPacked>(color), thickness, points, options);
        }
@ -215,7 +216,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(pen, new Polygon(new LinearLineSegment(points)), options);
        }
@ -230,7 +231,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPolygon(pen, new Polygon(new LinearLineSegment(points)));
        }
@ -249,7 +250,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPath<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, IPath path, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(new DrawPathProcessor<TColor, TPacked>(pen, path, options));
        }
@ -265,7 +266,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPath<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, IPath path)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(new DrawPathProcessor<TColor, TPacked>(pen, path, GraphicsOptions.Default));
        }
@ -285,7 +286,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPath<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, IPath path, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new Pen<TColor, TPacked>(brush, thickness), path, options);
        }
@ -302,7 +303,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPath<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, IPath path)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new Pen<TColor, TPacked>(brush, thickness), path);
        }
@ -322,7 +323,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawPath<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, IPath path, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new SolidBrush<TColor, TPacked>(color), thickness, path, options);
        }
@ -339,7 +340,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawPath<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, IPath path)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new SolidBrush<TColor, TPacked>(color), thickness, path);
        }
@ -359,7 +360,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawLines<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new Pen<TColor, TPacked>(brush, thickness), new Path(new LinearLineSegment(points)), options);
        }
@ -376,7 +377,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawLines<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new Pen<TColor, TPacked>(brush, thickness), new Path(new LinearLineSegment(points)));
        }
@ -393,7 +394,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawLines<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawLines(new SolidBrush<TColor, TPacked>(color), thickness, points);
        }
@ -413,7 +414,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawLines<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawLines(new SolidBrush<TColor, TPacked>(color), thickness, points, options);
        }
@ -432,7 +433,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawLines<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(pen, new Path(new LinearLineSegment(points)), options);
        }
@ -448,7 +449,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawLines<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(pen, new Path(new LinearLineSegment(points)));
        }
@ -468,7 +469,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawBeziers<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new Pen<TColor, TPacked>(brush, thickness), new Path(new BezierLineSegment(points)), options);
        }
@ -485,7 +486,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawBeziers<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, float thickness, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(new Pen<TColor, TPacked>(brush, thickness), new Path(new BezierLineSegment(points)));
        }
@ -502,7 +503,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawBeziers<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawBeziers(new SolidBrush<TColor, TPacked>(color), thickness, points);
        }
@ -522,7 +523,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawBeziers<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float thickness, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawBeziers(new SolidBrush<TColor, TPacked>(color), thickness, points, options);
        }
@ -541,7 +542,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> DrawBeziers<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(pen, new Path(new BezierLineSegment(points)), options);
        }
@ -557,7 +558,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> DrawBeziers<TColor, TPacked>(this Image<TColor, TPacked> source, IPen<TColor, TPacked> pen, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            return source.DrawPath(pen, new Path(new BezierLineSegment(points)));
        }
--- a/src/ImageSharp/Drawing/DrawImage.cs
+++ b/src/ImageSharp/Drawing/DrawImage.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -23,7 +25,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Blend<TColor, TPacked>(this Image<TColor, TPacked> source, Image<TColor, TPacked> image, int percent = 50)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return DrawImage(source, image, percent, default(Size), default(Point));
        }
@ -41,7 +43,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DrawImage<TColor, TPacked>(this Image<TColor, TPacked> source, Image<TColor, TPacked> image, int percent, Size size, Point location)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            if (size == default(Size))
            {
--- a/src/ImageSharp/Drawing/Fill.cs
+++ b/src/ImageSharp/Drawing/Fill.cs
@ -5,13 +5,13 @@

 namespace ImageSharp
 {
+    using System;
    using System.Numerics;
    using Drawing;
    using Drawing.Brushes;
    using Drawing.Paths;
    using Drawing.Processors;
    using Drawing.Shapes;
-    using Processors;

    /// <summary>
    /// Extension methods for the <see cref="Image{TColor, TPacked}"/> type.
@ -28,7 +28,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> Fill<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(new FillProcessor<TColor, TPacked>(brush));
        }
@ -43,7 +43,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> Fill<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Fill(new SolidBrush<TColor, TPacked>(color));
        }
@ -59,7 +59,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> Fill<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, IShape shape, GraphicsOptions options)
          where TColor : struct, IPackedPixel<TPacked>
-          where TPacked : struct
+          where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(new FillShapeProcessor<TColor, TPacked>(brush, shape, options));
        }
@ -75,7 +75,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> Fill<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, IShape shape)
          where TColor : struct, IPackedPixel<TPacked>
-          where TPacked : struct
+          where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(new FillShapeProcessor<TColor, TPacked>(brush, shape, GraphicsOptions.Default));
        }
@ -94,7 +94,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> Fill<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, IShape shape, GraphicsOptions options)
          where TColor : struct, IPackedPixel<TPacked>
-          where TPacked : struct
+          where TPacked : struct, IEquatable<TPacked>
        {
            return source.Fill(new SolidBrush<TColor, TPacked>(color), shape, options);
        }
@ -110,7 +110,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> Fill<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, IShape shape)
          where TColor : struct, IPackedPixel<TPacked>
-          where TPacked : struct
+          where TPacked : struct, IEquatable<TPacked>
        {
            return source.Fill(new SolidBrush<TColor, TPacked>(color), shape);
        }
@ -129,7 +129,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> FillPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            // using Polygon directly instead of LinearPolygon as its will have less indirection
            return source.Fill(brush, new Polygon(new LinearLineSegment(points)), options);
@ -146,7 +146,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> FillPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, IBrush<TColor, TPacked> brush, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            // using Polygon directly instead of LinearPolygon as its will have less indirection
            return source.Fill(brush, new Polygon(new LinearLineSegment(points)));
@ -166,7 +166,7 @@ namespace ImageSharp
        /// </returns>
        public static Image<TColor, TPacked> FillPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, Vector2[] points, GraphicsOptions options)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            // using Polygon directly instead of LinearPolygon as its will have less indirection
            return source.Fill(new SolidBrush<TColor, TPacked>(color), new Polygon(new LinearLineSegment(points)), options);
@ -183,7 +183,7 @@ namespace ImageSharp
        /// <returns>The Image</returns>
        public static Image<TColor, TPacked> FillPolygon<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, Vector2[] points)
           where TColor : struct, IPackedPixel<TPacked>
-           where TPacked : struct
+           where TPacked : struct, IEquatable<TPacked>
        {
            // using Polygon directly instead of LinearPolygon as its will have less indirection
            return source.Fill(new SolidBrush<TColor, TPacked>(color), new Polygon(new LinearLineSegment(points)));
--- a/src/ImageSharp/Drawing/Pens/IPen.cs
+++ b/src/ImageSharp/Drawing/Pens/IPen.cs
@ -15,7 +15,7 @@ namespace ImageSharp.Drawing.Pens
    /// <typeparam name="TPacked">The type of the packed.</typeparam>
    public interface IPen<TColor, TPacked>
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Creates the applicator for applying this pen to an Image
--- a/src/ImageSharp/Drawing/Pens/Pen.cs
+++ b/src/ImageSharp/Drawing/Pens/Pen.cs
@ -72,9 +72,9 @@ namespace ImageSharp.Drawing.Pens
    /// section 3 will be width/2 long and will be filled
    /// the the pattern will imidiatly repeat without gap.
    /// </remarks>
-    public partial class Pen<TColor, TPacked> : IPen<TColor, TPacked>
+    public class Pen<TColor, TPacked> : IPen<TColor, TPacked>
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
    {
        private static readonly float[] EmptyPattern = new float[0];
        private readonly float[] pattern;
--- a/src/ImageSharp/Drawing/Pens/Pens.cs
+++ b/src/ImageSharp/Drawing/Pens/Pens.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Drawing.Pens
 {
+    using System;
+
    /// <summary>
    /// Common Pen styles
    /// </summary>
@ -108,7 +110,7 @@ namespace ImageSharp.Drawing.Pens
    /// <typeparam name="TPacked">The type of the packed.</typeparam>
    public partial class Pens<TColor, TPacked>
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
    {
        private static readonly float[] DashDotPattern = new[] { 3f, 1f, 1f, 1f };
        private static readonly float[] DashDotDotPattern = new[] { 3f, 1f, 1f, 1f, 1f, 1f };
--- a/src/ImageSharp/Drawing/Pens/Processors/ColoredPointInfo.cs
+++ b/src/ImageSharp/Drawing/Pens/Processors/ColoredPointInfo.cs
@ -5,14 +5,16 @@

 namespace ImageSharp.Drawing.Pens.Processors
 {
+    using System;
+
    /// <summary>
-    /// Returns details about how far awau from the inside of a shape and the color the pixel could be.
+    /// Returns details about how far away from the inside of a shape and the color the pixel could be.
    /// </summary>
    /// <typeparam name="TColor">The type of the color.</typeparam>
    /// <typeparam name="TPacked">The type of the packed.</typeparam>
    public struct ColoredPointInfo<TColor, TPacked>
-            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+        where TColor : struct, IPackedPixel<TPacked>
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The color
--- a/src/ImageSharp/Drawing/Pens/Processors/IPenApplicator.cs
+++ b/src/ImageSharp/Drawing/Pens/Processors/IPenApplicator.cs
@ -15,7 +15,7 @@ namespace ImageSharp.Drawing.Pens.Processors
    /// <typeparam name="TPacked">The type of the packed.</typeparam>
    public interface IPenApplicator<TColor, TPacked> : IDisposable
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Gets the required region.
--- a/src/ImageSharp/Drawing/Processors/DrawImageProcessor.cs
+++ b/src/ImageSharp/Drawing/Processors/DrawImageProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class DrawImageProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="DrawImageProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Drawing/Processors/DrawPathProcessor.cs
+++ b/src/ImageSharp/Drawing/Processors/DrawPathProcessor.cs
@ -24,7 +24,7 @@ namespace ImageSharp.Drawing.Processors
    /// <seealso cref="ImageSharp.Processors.ImageFilteringProcessor{TColor, TPacked}" />
    public class DrawPathProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        private const float AntialiasFactor = 1f;
        private const int PaddingFactor = 1; // needs to been the same or greater than AntialiasFactor
--- a/src/ImageSharp/Drawing/Processors/FillProcessor.cs
+++ b/src/ImageSharp/Drawing/Processors/FillProcessor.cs
@ -19,7 +19,7 @@ namespace ImageSharp.Drawing.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class FillProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        private const float Epsilon = 0.001f;

--- a/src/ImageSharp/Drawing/Processors/FillShapeProcessor.cs
+++ b/src/ImageSharp/Drawing/Processors/FillShapeProcessor.cs
@ -20,7 +20,7 @@ namespace ImageSharp.Drawing.Processors
    /// <seealso cref="ImageSharp.Processors.ImageFilteringProcessor{TColor, TPacked}" />
    public class FillShapeProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        private const float Epsilon = 0.001f;

--- a/src/ImageSharp/Filters/Binarization/BinaryThreshold.cs
+++ b/src/ImageSharp/Filters/Binarization/BinaryThreshold.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BinaryThreshold<TColor, TPacked>(this Image<TColor, TPacked> source, float threshold)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return BinaryThreshold(source, threshold, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BinaryThreshold<TColor, TPacked>(this Image<TColor, TPacked> source, float threshold, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new BinaryThresholdProcessor<TColor, TPacked>(threshold));
        }
--- a/src/ImageSharp/Filters/ColorMatrix/BlackWhite.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/BlackWhite.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BlackWhite<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return BlackWhite(source, source.Bounds);
        }
@ -38,7 +40,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BlackWhite<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new BlackWhiteProcessor<TColor, TPacked>());
        }
--- a/src/ImageSharp/Filters/ColorMatrix/ColorBlindness.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/ColorBlindness.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> ColorBlindness<TColor, TPacked>(this Image<TColor, TPacked> source, ColorBlindness colorBlindness)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return ColorBlindness(source, colorBlindness, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> ColorBlindness<TColor, TPacked>(this Image<TColor, TPacked> source, ColorBlindness colorBlindness, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            IImageFilteringProcessor<TColor, TPacked> processor;

--- a/src/ImageSharp/Filters/ColorMatrix/Grayscale.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Grayscale.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Grayscale<TColor, TPacked>(this Image<TColor, TPacked> source, GrayscaleMode mode = GrayscaleMode.Bt709)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Grayscale(source, source.Bounds, mode);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Grayscale<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle, GrayscaleMode mode = GrayscaleMode.Bt709)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            IImageFilteringProcessor<TColor, TPacked> processor = mode == GrayscaleMode.Bt709
                ? (IImageFilteringProcessor<TColor, TPacked>)new GrayscaleBt709Processor<TColor, TPacked>()
--- a/src/ImageSharp/Filters/ColorMatrix/Hue.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Hue.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Hue<TColor, TPacked>(this Image<TColor, TPacked> source, float degrees)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Hue(source, degrees, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Hue<TColor, TPacked>(this Image<TColor, TPacked> source, float degrees, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new HueProcessor<TColor, TPacked>(degrees));
        }
--- a/src/ImageSharp/Filters/ColorMatrix/Kodachrome.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Kodachrome.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Kodachrome<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Kodachrome(source, source.Bounds);
        }
@ -38,7 +40,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Kodachrome<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new KodachromeProcessor<TColor, TPacked>());
        }
--- a/src/ImageSharp/Filters/ColorMatrix/Lomograph.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Lomograph.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Lomograph<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Lomograph(source, source.Bounds);
        }
@ -38,7 +40,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Lomograph<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new LomographProcessor<TColor, TPacked>());
        }
--- a/src/ImageSharp/Filters/ColorMatrix/Polaroid.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Polaroid.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Polaroid<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Polaroid(source, source.Bounds);
        }
@ -38,7 +40,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Polaroid<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new PolaroidProcessor<TColor, TPacked>());
        }
--- a/src/ImageSharp/Filters/ColorMatrix/Saturation.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Saturation.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Saturation<TColor, TPacked>(this Image<TColor, TPacked> source, int amount)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Saturation(source, amount, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Saturation<TColor, TPacked>(this Image<TColor, TPacked> source, int amount, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new SaturationProcessor<TColor, TPacked>(amount));
        }
--- a/src/ImageSharp/Filters/ColorMatrix/Sepia.cs
+++ b/src/ImageSharp/Filters/ColorMatrix/Sepia.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image"/>.</returns>
        public static Image<TColor, TPacked> Sepia<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Sepia(source, source.Bounds);
        }
@ -38,7 +40,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image"/>.</returns>
        public static Image<TColor, TPacked> Sepia<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new SepiaProcessor<TColor, TPacked>());
        }
--- a/src/ImageSharp/Filters/Convolution/BoxBlur.cs
+++ b/src/ImageSharp/Filters/Convolution/BoxBlur.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BoxBlur<TColor, TPacked>(this Image<TColor, TPacked> source, int radius = 7)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return BoxBlur(source, radius, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BoxBlur<TColor, TPacked>(this Image<TColor, TPacked> source, int radius, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new BoxBlurProcessor<TColor, TPacked>(radius));
        }
--- a/src/ImageSharp/Filters/Convolution/DetectEdges.cs
+++ b/src/ImageSharp/Filters/Convolution/DetectEdges.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DetectEdges<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return DetectEdges(source, source.Bounds, new SobelProcessor<TColor, TPacked> { Grayscale = true });
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DetectEdges<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return DetectEdges(source, rectangle, new SobelProcessor<TColor, TPacked> { Grayscale = true });
        }
@ -56,7 +58,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DetectEdges<TColor, TPacked>(this Image<TColor, TPacked> source, EdgeDetection filter, bool grayscale = true)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return DetectEdges(source, filter, source.Bounds, grayscale);
        }
@ -75,7 +77,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DetectEdges<TColor, TPacked>(this Image<TColor, TPacked> source, EdgeDetection filter, Rectangle rectangle, bool grayscale = true)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            IEdgeDetectorProcessor<TColor, TPacked> processor;

@ -135,7 +137,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DetectEdges<TColor, TPacked>(this Image<TColor, TPacked> source, IEdgeDetectorProcessor<TColor, TPacked> filter)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return DetectEdges(source, source.Bounds, filter);
        }
@ -153,7 +155,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> DetectEdges<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle, IEdgeDetectorProcessor<TColor, TPacked> filter)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, filter);
        }
--- a/src/ImageSharp/Filters/Convolution/GaussianBlur.cs
+++ b/src/ImageSharp/Filters/Convolution/GaussianBlur.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> GaussianBlur<TColor, TPacked>(this Image<TColor, TPacked> source, float sigma = 3f)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return GaussianBlur(source, sigma, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> GaussianBlur<TColor, TPacked>(this Image<TColor, TPacked> source, float sigma, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new GaussianBlurProcessor<TColor, TPacked>(sigma));
        }
--- a/src/ImageSharp/Filters/Convolution/GaussianSharpen.cs
+++ b/src/ImageSharp/Filters/Convolution/GaussianSharpen.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> GaussianSharpen<TColor, TPacked>(this Image<TColor, TPacked> source, float sigma = 3f)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return GaussianSharpen(source, sigma, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> GaussianSharpen<TColor, TPacked>(this Image<TColor, TPacked> source, float sigma, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new GaussianSharpenProcessor<TColor, TPacked>(sigma));
        }
--- a/src/ImageSharp/Filters/Effects/Alpha.cs
+++ b/src/ImageSharp/Filters/Effects/Alpha.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Alpha<TColor, TPacked>(this Image<TColor, TPacked> source, int percent)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Alpha(source, percent, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image"/>.</returns>
        public static Image<TColor, TPacked> Alpha<TColor, TPacked>(this Image<TColor, TPacked> source, int percent, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new AlphaProcessor<TColor, TPacked>(percent));
        }
--- a/src/ImageSharp/Filters/Effects/BackgroundColor.cs
+++ b/src/ImageSharp/Filters/Effects/BackgroundColor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> BackgroundColor<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(source.Bounds, new BackgroundColorProcessor<TColor, TPacked>(color));
        }
--- a/src/ImageSharp/Filters/Effects/Brightness.cs
+++ b/src/ImageSharp/Filters/Effects/Brightness.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Brightness<TColor, TPacked>(this Image<TColor, TPacked> source, int amount)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Brightness(source, amount, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Brightness<TColor, TPacked>(this Image<TColor, TPacked> source, int amount, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new BrightnessProcessor<TColor, TPacked>(amount));
        }
--- a/src/ImageSharp/Filters/Effects/Contrast.cs
+++ b/src/ImageSharp/Filters/Effects/Contrast.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -22,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Contrast<TColor, TPacked>(this Image<TColor, TPacked> source, int amount)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Contrast(source, amount, source.Bounds);
        }
@ -40,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Contrast<TColor, TPacked>(this Image<TColor, TPacked> source, int amount, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new ContrastProcessor<TColor, TPacked>(amount));
        }
--- a/src/ImageSharp/Filters/Effects/Invert.cs
+++ b/src/ImageSharp/Filters/Effects/Invert.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image"/>.</returns>
        public static Image<TColor, TPacked> Invert<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Invert(source, source.Bounds);
        }
@ -38,7 +40,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image"/>.</returns>
        public static Image<TColor, TPacked> Invert<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return source.Process(rectangle, new InvertProcessor<TColor, TPacked>());
        }
--- a/src/ImageSharp/Filters/Effects/OilPainting.cs
+++ b/src/ImageSharp/Filters/Effects/OilPainting.cs
@ -25,7 +25,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> OilPaint<TColor, TPacked>(this Image<TColor, TPacked> source, int levels = 10, int brushSize = 15)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return OilPaint(source, levels, brushSize, source.Bounds);
        }
@ -44,7 +44,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> OilPaint<TColor, TPacked>(this Image<TColor, TPacked> source, int levels, int brushSize, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            Guard.MustBeGreaterThan(levels, 0, nameof(levels));

--- a/src/ImageSharp/Filters/Effects/Pixelate.cs
+++ b/src/ImageSharp/Filters/Effects/Pixelate.cs
@ -24,7 +24,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Pixelate<TColor, TPacked>(this Image<TColor, TPacked> source, int size = 4)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Pixelate(source, size, source.Bounds);
        }
@ -42,7 +42,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Pixelate<TColor, TPacked>(this Image<TColor, TPacked> source, int size, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            if (size <= 0 || size > source.Height || size > source.Width)
            {
--- a/src/ImageSharp/Filters/Overlays/Glow.cs
+++ b/src/ImageSharp/Filters/Overlays/Glow.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Glow<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Glow(source, default(TColor), source.Bounds.Width * .5F, source.Bounds);
        }
@ -36,7 +38,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Glow<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Glow(source, color, source.Bounds.Width * .5F, source.Bounds);
        }
@ -51,7 +53,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Glow<TColor, TPacked>(this Image<TColor, TPacked> source, float radius)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Glow(source, default(TColor), radius, source.Bounds);
        }
@ -68,7 +70,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Glow<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Glow(source, default(TColor), 0, rectangle);
        }
@ -87,7 +89,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Glow<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float radius, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            GlowProcessor<TColor, TPacked> processor = new GlowProcessor<TColor, TPacked> { Radius = radius, };

--- a/src/ImageSharp/Filters/Overlays/Vignette.cs
+++ b/src/ImageSharp/Filters/Overlays/Vignette.cs
@ -5,6 +5,8 @@

 namespace ImageSharp
 {
+    using System;
+
    using Processors;

    /// <summary>
@ -21,7 +23,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Vignette<TColor, TPacked>(this Image<TColor, TPacked> source)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Vignette(source, default(TColor), source.Bounds.Width * .5F, source.Bounds.Height * .5F, source.Bounds);
        }
@ -36,7 +38,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Vignette<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Vignette(source, color, source.Bounds.Width * .5F, source.Bounds.Height * .5F, source.Bounds);
        }
@ -52,7 +54,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Vignette<TColor, TPacked>(this Image<TColor, TPacked> source, float radiusX, float radiusY)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Vignette(source, default(TColor), radiusX, radiusY, source.Bounds);
        }
@ -69,7 +71,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Vignette<TColor, TPacked>(this Image<TColor, TPacked> source, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            return Vignette(source, default(TColor), 0, 0, rectangle);
        }
@ -89,7 +91,7 @@ namespace ImageSharp
        /// <returns>The <see cref="Image{TColor, TPacked}"/>.</returns>
        public static Image<TColor, TPacked> Vignette<TColor, TPacked>(this Image<TColor, TPacked> source, TColor color, float radiusX, float radiusY, Rectangle rectangle)
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
        {
            VignetteProcessor<TColor, TPacked> processor = new VignetteProcessor<TColor, TPacked> { RadiusX = radiusX, RadiusY = radiusY };

--- a/src/ImageSharp/Filters/Processors/Binarization/BinaryThresholdProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Binarization/BinaryThresholdProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class BinaryThresholdProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="BinaryThresholdProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/BlackWhiteProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/BlackWhiteProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class BlackWhiteProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/AchromatomalyProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/AchromatomalyProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class AchromatomalyProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/AchromatopsiaProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/AchromatopsiaProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class AchromatopsiaProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/DeuteranomalyProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/DeuteranomalyProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class DeuteranomalyProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/DeuteranopiaProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/DeuteranopiaProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class DeuteranopiaProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/ProtanomalyProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/ProtanomalyProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class ProtanomalyProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/ProtanopiaProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/ProtanopiaProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class ProtanopiaProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/TritanomalyProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/TritanomalyProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class TritanomalyProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/TritanopiaProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorBlindness/TritanopiaProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class TritanopiaProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/ColorMatrixFilter.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/ColorMatrixFilter.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public abstract class ColorMatrixFilter<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>, IColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public abstract Matrix4x4 Matrix { get; }
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/GrayscaleBt601Processor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/GrayscaleBt601Processor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class GrayscaleBt601Processor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/GrayscaleBt709Processor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/GrayscaleBt709Processor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class GrayscaleBt709Processor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/HueProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/HueProcessor.cs
@ -15,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class HueProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="HueProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/IColorMatrixFilter.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/IColorMatrixFilter.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public interface IColorMatrixFilter<TColor, TPacked> : IImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Gets the <see cref="Matrix4x4"/> used to alter the image.
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/KodachromeProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/KodachromeProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class KodachromeProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/LomographProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/LomographProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class LomographProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/PolaroidProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/PolaroidProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class PolaroidProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4()
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/SaturationProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/SaturationProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -14,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class SaturationProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="SaturationProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/ColorMatrix/SepiaProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ColorMatrix/SepiaProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;

    /// <summary>
@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class SepiaProcessor<TColor, TPacked> : ColorMatrixFilter<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public override Matrix4x4 Matrix => new Matrix4x4
--- a/src/ImageSharp/Filters/Processors/Convolution/BoxBlurProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/BoxBlurProcessor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Processors
 {
+    using System;
+
    /// <summary>
    /// Applies a Box blur sampler to the image.
    /// </summary>
@ -12,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class BoxBlurProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The maximum size of the kernel in either direction.
--- a/src/ImageSharp/Filters/Processors/Convolution/Convolution2DProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/Convolution2DProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class Convolution2DProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="Convolution2DProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Convolution/Convolution2PassProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/Convolution2PassProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;
    using System.Threading.Tasks;

@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class Convolution2PassProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="Convolution2PassProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Convolution/ConvolutionProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/ConvolutionProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Numerics;
    using System.Threading.Tasks;

@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class ConvolutionProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="ConvolutionProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/EdgeDetector2DProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/EdgeDetector2DProcessor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Processors
 {
+    using System;
+
    /// <summary>
    /// Defines a sampler that detects edges within an image using two one-dimensional matrices.
    /// </summary>
@ -12,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public abstract class EdgeDetector2DProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>, IEdgeDetectorProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Gets the horizontal gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/EdgeDetectorCompassProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/EdgeDetectorCompassProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public abstract class EdgeDetectorCompassProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>, IEdgeDetectorProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Gets the North gradient operator
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/EdgeDetectorProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/EdgeDetectorProcessor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Processors
 {
+    using System;
+
    /// <summary>
    /// Defines a sampler that detects edges within an image using a single two dimensional matrix.
    /// </summary>
@ -12,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public abstract class EdgeDetectorProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>, IEdgeDetectorProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public bool Grayscale { get; set; }
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/IEdgeDetectorProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/IEdgeDetectorProcessor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Processors
 {
+    using System;
+
    /// <summary>
    /// Provides properties and methods allowing the detection of edges within an image.
    /// </summary>
@ -12,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public interface IEdgeDetectorProcessor<TColor, TPacked> : IImageFilteringProcessor<TColor, TPacked>, IEdgeDetectorProcessor
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
    }

--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/KayyaliProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/KayyaliProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class KayyaliProcessor<TColor, TPacked> : EdgeDetector2DProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The horizontal gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/KirschProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/KirschProcessor.cs
@ -4,6 +4,7 @@
 // </copyright>
 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class KirschProcessor<TColor, TPacked> : EdgeDetectorCompassProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The North gradient operator
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/Laplacian3X3Processor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/Laplacian3X3Processor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class Laplacian3X3Processor<TColor, TPacked> : EdgeDetectorProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The 2d gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/Laplacian5X5Processor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/Laplacian5X5Processor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class Laplacian5X5Processor<TColor, TPacked> : EdgeDetectorProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The 2d gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/LaplacianOfGaussianProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/LaplacianOfGaussianProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class LaplacianOfGaussianProcessor<TColor, TPacked> : EdgeDetectorProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The 2d gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/PrewittProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/PrewittProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class PrewittProcessor<TColor, TPacked> : EdgeDetector2DProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The horizontal gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/RobertsCrossProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/RobertsCrossProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class RobertsCrossProcessor<TColor, TPacked> : EdgeDetector2DProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The horizontal gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/RobinsonProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/RobinsonProcessor.cs
@ -4,6 +4,7 @@
 // </copyright>
 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -15,7 +16,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class RobinsonProcessor<TColor, TPacked> : EdgeDetectorCompassProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The North gradient operator
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/ScharrProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/ScharrProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class ScharrProcessor<TColor, TPacked> : EdgeDetector2DProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The horizontal gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/SobelProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/EdgeDetection/SobelProcessor.cs
@ -5,6 +5,7 @@

 namespace ImageSharp.Processors
 {
+    using System;
    using System.Diagnostics.CodeAnalysis;

    /// <summary>
@ -16,7 +17,7 @@ namespace ImageSharp.Processors
    [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
    public class SobelProcessor<TColor, TPacked> : EdgeDetector2DProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The horizontal gradient operator.
--- a/src/ImageSharp/Filters/Processors/Convolution/GaussianBlurProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/GaussianBlurProcessor.cs
@ -14,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class GaussianBlurProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The maximum size of the kernel in either direction.
--- a/src/ImageSharp/Filters/Processors/Convolution/GaussianSharpenProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Convolution/GaussianSharpenProcessor.cs
@ -14,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class GaussianSharpenProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The maximum size of the kernel in either direction.
--- a/src/ImageSharp/Filters/Processors/Effects/AlphaProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/AlphaProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class AlphaProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="AlphaProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Effects/BackgroundColorProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/BackgroundColorProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class BackgroundColorProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// The epsilon for comparing floating point numbers.
--- a/src/ImageSharp/Filters/Processors/Effects/BrightnessProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/BrightnessProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class BrightnessProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="BrightnessProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Effects/ContrastProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/ContrastProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>long, float.</example></typeparam>
    public class ContrastProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="ContrastProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Effects/InvertProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/InvertProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class InvertProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        protected override void OnApply(ImageBase<TColor, TPacked> source, Rectangle sourceRectangle)
--- a/src/ImageSharp/Filters/Processors/Effects/OilPaintingProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/OilPaintingProcessor.cs
@ -17,7 +17,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class OilPaintingProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="OilPaintingProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Effects/PixelateProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Effects/PixelateProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class PixelateProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="PixelateProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/IImageFilteringProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/IImageFilteringProcessor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Processors
 {
+    using System;
+
    /// <summary>
    /// Encapsulates methods to alter the pixels of an image. The processor operates on the original source pixels.
    /// </summary>
@ -12,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public interface IImageFilteringProcessor<TColor, TPacked> : IImageProcessor
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Applies the process to the specified portion of the specified <see cref="ImageBase{T, TP}"/>.
--- a/src/ImageSharp/Filters/Processors/ImageFilteringProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/ImageFilteringProcessor.cs
@ -14,7 +14,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public abstract class ImageFilteringProcessor<TColor, TPacked> : ImageProcessor<TColor, TPacked>, IImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <inheritdoc/>
        public void Apply(ImageBase<TColor, TPacked> source, Rectangle sourceRectangle)
--- a/src/ImageSharp/Filters/Processors/Overlays/GlowProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Overlays/GlowProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class GlowProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
            where TColor : struct, IPackedPixel<TPacked>
-            where TPacked : struct
+            where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="GlowProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Overlays/VignetteProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Overlays/VignetteProcessor.cs
@ -16,7 +16,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class VignetteProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="VignetteProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Transforms/CompandingResizeProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Transforms/CompandingResizeProcessor.cs
@ -17,7 +17,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class CompandingResizeProcessor<TColor, TPacked> : ResamplingWeightedProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="CompandingResizeProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Transforms/CropProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Transforms/CropProcessor.cs
@ -15,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class CropProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="CropProcessor{TColor,TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Transforms/EntropyCropProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Transforms/EntropyCropProcessor.cs
@ -5,6 +5,8 @@

 namespace ImageSharp.Processors
 {
+    using System;
+
    /// <summary>
    /// Provides methods to allow the cropping of an image to preserve areas of highest
    /// entropy.
@ -13,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class EntropyCropProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="EntropyCropProcessor{TColor, TPacked}"/> class.
--- a/src/ImageSharp/Filters/Processors/Transforms/FlipProcessor.cs
+++ b/src/ImageSharp/Filters/Processors/Transforms/FlipProcessor.cs
@ -15,7 +15,7 @@ namespace ImageSharp.Processors
    /// <typeparam name="TPacked">The packed format. <example>uint, long, float.</example></typeparam>
    public class FlipProcessor<TColor, TPacked> : ImageFilteringProcessor<TColor, TPacked>
        where TColor : struct, IPackedPixel<TPacked>
-        where TPacked : struct
+        where TPacked : struct, IEquatable<TPacked>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="FlipProcessor{TColor, TPacked}"/> class.