Update WuFrameQuantizer{TPixel}.cs

src/ImageSharp/Processing/Processors/Quantization/WuFrameQuantizer{TPixel}.cs

@@ -5,7 +5,6 @@ using System;
 using System.Buffers;
 using System.Numerics;
 using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
 using SixLabors.ImageSharp.Advanced;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
@@ -784,94 +783,6 @@ namespace SixLabors.ImageSharp.Processing.Processors.Quantization
                 => new Vector4(this.R, this.G, this.B, this.A) / this.Weight / 255F;
         }
 
-        private struct Moment
-        {
-            /// <summary>
-            /// Moment of <c>r*P(c)</c>.
-            /// </summary>
-            public long R;
-
-            /// <summary>
-            /// Moment of <c>g*P(c)</c>.
-            /// </summary>
-            public long G;
-
-            /// <summary>
-            /// Moment of <c>b*P(c)</c>.
-            /// </summary>
-            public long B;
-
-            /// <summary>
-            /// Moment of <c>a*P(c)</c>.
-            /// </summary>
-            public long A;
-
-            /// <summary>
-            /// Moment of <c>P(c)</c>.
-            /// </summary>
-            public long Weight;
-
-            /// <summary>
-            /// Moment of <c>c^2*P(c)</c>.
-            /// </summary>
-            public double Moment2;
-
-            [MethodImpl(InliningOptions.ShortMethod)]
-            public static Moment operator +(Moment x, Moment y)
-            {
-                x.R += y.R;
-                x.G += y.G;
-                x.B += y.B;
-                x.A += y.A;
-                x.Weight += y.Weight;
-                x.Moment2 += y.Moment2;
-                return x;
-            }
-
-            [MethodImpl(InliningOptions.ShortMethod)]
-            public static Moment operator -(Moment x, Moment y)
-            {
-                x.R -= y.R;
-                x.G -= y.G;
-                x.B -= y.B;
-                x.A -= y.A;
-                x.Weight -= y.Weight;
-                x.Moment2 -= y.Moment2;
-                return x;
-            }
-
-            [MethodImpl(InliningOptions.ShortMethod)]
-            public static Moment operator -(Moment x)
-            {
-                x.R = -x.R;
-                x.G = -x.G;
-                x.B = -x.B;
-                x.A = -x.A;
-                x.Weight = -x.Weight;
-                x.Moment2 = -x.Moment2;
-                return x;
-            }
-
-            [MethodImpl(InliningOptions.ShortMethod)]
-            public static Moment operator +(Moment x, Rgba32 y)
-            {
-                x.R += y.R;
-                x.G += y.G;
-                x.B += y.B;
-                x.A += y.A;
-                x.Weight++;
-
-                var vector = new Vector4(y.R, y.G, y.B, y.A);
-                x.Moment2 += Vector4.Dot(vector, vector);
-
-                return x;
-            }
-
-            [MethodImpl(InliningOptions.ShortMethod)]
-            public readonly Vector4 Normalize()
-                => new Vector4(this.R, this.G, this.B, this.A) / this.Weight / 255F;
-        }
-
         /// <summary>
         /// Represents a box color cube.
         /// </summary>