Merge pull request #137 from JimBobSquarePants/Interalize-all-the-things

Internalize all the things!

README.md

@@ -93,12 +93,6 @@ using (Image image = new Image(stream))
 }
 ```
 
-Individual processors can be initialised and apply processing against images. This allows nesting which brings the potential for powerful combinations of processing methods:
-
-```csharp
-new BrightnessProcessor(50).Apply(sourceImage, sourceImage.Bounds);
-```
-
 Setting individual pixel values is perfomed as follows:
 
 ```csharp

src/ImageSharp.Drawing/ImageSharp.Drawing.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <Description>An extension to ImageSharp that allows the drawing of images, paths, and text.</Description>
     <AssemblyTitle>ImageSharp.Drawing</AssemblyTitle>
-    <VersionPrefix>1.0.0-alpha3</VersionPrefix>
+    <VersionPrefix>1.0.0-alpha4</VersionPrefix>
     <Authors>James Jackson-South and contributors</Authors>
     <TargetFramework>netstandard1.1</TargetFramework>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>

src/ImageSharp.Drawing/Processors/DrawImageProcessor.cs

@@ -15,7 +15,7 @@ namespace ImageSharp.Drawing.Processors
     /// Combines two images together by blending the pixels.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class DrawImageProcessor<TColor> : ImageProcessor<TColor>
+    internal class DrawImageProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp.Drawing/Processors/DrawPathProcessor.cs

@@ -17,7 +17,7 @@ namespace ImageSharp.Drawing.Processors
     /// </summary>
     /// <typeparam name="TColor">The type of the color.</typeparam>
     /// <seealso cref="ImageSharp.Processing.ImageProcessor{TColor}" />
-    public class DrawPathProcessor<TColor> : ImageProcessor<TColor>
+    internal class DrawPathProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         private const float AntialiasFactor = 1f;

src/ImageSharp.Drawing/Processors/FillProcessor.cs

@@ -16,8 +16,8 @@ namespace ImageSharp.Drawing.Processors
     /// Using the bursh as a source of pixels colors blends the brush color with source.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class FillProcessor<TColor> : ImageProcessor<TColor>
+    internal class FillProcessor<TColor> : ImageProcessor<TColor>
-    where TColor : struct, IPixel<TColor>
+        where TColor : struct, IPixel<TColor>
     {
         /// <summary>
         /// The brush.

src/ImageSharp.Drawing/Processors/FillRegionProcessor.cs

@@ -17,7 +17,7 @@ namespace ImageSharp.Drawing.Processors
     /// </summary>
     /// <typeparam name="TColor">The type of the color.</typeparam>
     /// <seealso cref="ImageSharp.Processing.ImageProcessor{TColor}" />
-    public class FillRegionProcessor<TColor> : ImageProcessor<TColor>
+    internal class FillRegionProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         private const float AntialiasFactor = 1f;

src/ImageSharp/Common/Memory/Fast2DArray{T}.cs

@@ -13,7 +13,7 @@ namespace ImageSharp
     /// Provides fast access to 2D arrays.
     /// </summary>
     /// <typeparam name="T">The type of elements in the array.</typeparam>
-    public struct Fast2DArray<T>
+    internal struct Fast2DArray<T>
     {
         /// <summary>
         /// The 1D representation of the 2D array.

src/ImageSharp/Common/Memory/PixelDataPool{T}.cs

@@ -12,7 +12,7 @@ namespace ImageSharp
     /// Provides a resource pool that enables reusing instances of value type arrays for image data <see cref="T:T[]"/>.
     /// </summary>
     /// <typeparam name="T">The value type.</typeparam>
-    public class PixelDataPool<T>
+    internal class PixelDataPool<T>
         where T : struct
     {
         /// <summary>

src/ImageSharp/Dithering/ErrorDiffusion/ErrorDiffuser.cs

@@ -5,12 +5,11 @@
 
 namespace ImageSharp.Dithering
 {
-    using System;
     using System.Numerics;
     using System.Runtime.CompilerServices;
 
     /// <summary>
-    /// The base class for performing effor diffusion based dithering.
+    /// The base class for performing error diffusion based dithering.
     /// </summary>
     public abstract class ErrorDiffuser : IErrorDiffuser
     {
@@ -34,19 +33,24 @@ namespace ImageSharp.Dithering
         /// </summary>
         private readonly int startingOffset;
 
+        /// <summary>
+        /// The diffusion matrix
+        /// </summary>
+        private readonly Fast2DArray<float> matrix;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="ErrorDiffuser"/> class.
         /// </summary>
         /// <param name="matrix">The dithering matrix.</param>
         /// <param name="divisor">The divisor.</param>
-        protected ErrorDiffuser(Fast2DArray<float> matrix, byte divisor)
+        internal ErrorDiffuser(Fast2DArray<float> matrix, byte divisor)
         {
             Guard.NotNull(matrix, nameof(matrix));
             Guard.MustBeGreaterThan(divisor, 0, nameof(divisor));
 
-            this.Matrix = matrix;
+            this.matrix = matrix;
-            this.matrixWidth = this.Matrix.Width;
+            this.matrixWidth = this.matrix.Width;
-            this.matrixHeight = this.Matrix.Height;
+            this.matrixHeight = this.matrix.Height;
             this.divisorVector = new Vector4(divisor);
 
             this.startingOffset = 0;
@@ -62,9 +66,6 @@ namespace ImageSharp.Dithering
             }
         }
 
-        /// <inheritdoc />
-        public Fast2DArray<float> Matrix { get; }
-
         /// <inheritdoc />
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Dither<TColor>(PixelAccessor<TColor> pixels, TColor source, TColor transformed, int x, int y, int width, int height)
@@ -87,9 +88,9 @@ namespace ImageSharp.Dithering
 
                     if (matrixX > 0 && matrixX < width && matrixY > 0 && matrixY < height)
                     {
-                        float coefficient = this.Matrix[row, col];
+                        float coefficient = this.matrix[row, col];
 
-                        // Good to disable here as we are not comparing matematical output.
+                        // Good to disable here as we are not comparing mathematical output.
                         // ReSharper disable once CompareOfFloatsByEqualityOperator
                         if (coefficient == 0)
                         {

src/ImageSharp/Dithering/ErrorDiffusion/IErrorDiffuser.cs

@@ -12,11 +12,6 @@ namespace ImageSharp.Dithering
     /// </summary>
     public interface IErrorDiffuser
     {
-        /// <summary>
-        /// Gets the dithering matrix
-        /// </summary>
-        Fast2DArray<float> Matrix { get; }
-
         /// <summary>
         /// Transforms the image applying the dither matrix. This method alters the input pixels array
         /// </summary>

src/ImageSharp/Dithering/Ordered/Bayer.cs

@@ -5,13 +5,11 @@
 
 namespace ImageSharp.Dithering.Ordered
 {
-    using System;
-
     /// <summary>
     /// Applies error diffusion based dithering using the 4x4 Bayer dithering matrix.
     /// <see href="http://www.efg2.com/Lab/Library/ImageProcessing/DHALF.TXT"/>
     /// </summary>
-    public class Bayer : IOrderedDither
+    public sealed class Bayer : OrderedDither4x4
     {
         /// <summary>
         /// The threshold matrix.
@@ -26,15 +24,12 @@ namespace ImageSharp.Dithering.Ordered
                 { 255, 127, 223, 95 }
             };
 
-        /// <inheritdoc />
+        /// <summary>
-        public Fast2DArray<byte> Matrix { get; } = ThresholdMatrix;
+        /// Initializes a new instance of the <see cref="Bayer"/> class.
-
+        /// </summary>
-        /// <inheritdoc />
+        public Bayer()
-        public void Dither<TColor>(PixelAccessor<TColor> pixels, TColor source, TColor upper, TColor lower, byte[] bytes, int index, int x, int y, int width, int height)
+            : base(ThresholdMatrix)
-            where TColor : struct, IPixel<TColor>
         {
-            source.ToXyzwBytes(bytes, 0);
-            pixels[x, y] = ThresholdMatrix[y % 3, x % 3] >= bytes[index] ? lower : upper;
         }
     }
 }

src/ImageSharp/Dithering/Ordered/IOrderedDither.cs

@@ -5,18 +5,11 @@
 
 namespace ImageSharp.Dithering
 {
-    using System;
-
     /// <summary>
     /// Encapsulates properties and methods required to perfom ordered dithering on an image.
     /// </summary>
     public interface IOrderedDither
     {
-        /// <summary>
-        /// Gets the dithering matrix
-        /// </summary>
-        Fast2DArray<byte> Matrix { get; }
-
         /// <summary>
         /// Transforms the image applying the dither matrix. This method alters the input pixels array
         /// </summary>
@@ -34,4 +27,4 @@ namespace ImageSharp.Dithering
         void Dither<TColor>(PixelAccessor<TColor> pixels, TColor source, TColor upper, TColor lower, byte[] bytes, int index, int x, int y, int width, int height)
             where TColor : struct, IPixel<TColor>;
     }
-}
+}

src/ImageSharp/Dithering/Ordered/Ordered.cs

@@ -5,13 +5,11 @@
 
 namespace ImageSharp.Dithering.Ordered
 {
-    using System;
-
     /// <summary>
     /// Applies error diffusion based dithering using the 4x4 ordered dithering matrix.
     /// <see href="https://en.wikipedia.org/wiki/Ordered_dithering"/>
     /// </summary>
-    public class Ordered : IOrderedDither
+    public sealed class Ordered : OrderedDither4x4
     {
         /// <summary>
         /// The threshold matrix.
@@ -26,15 +24,12 @@ namespace ImageSharp.Dithering.Ordered
                { 240, 112, 208, 80 }
             };
 
-        /// <inheritdoc />
+        /// <summary>
-        public Fast2DArray<byte> Matrix { get; } = ThresholdMatrix;
+        /// Initializes a new instance of the <see cref="Ordered"/> class.
-
+        /// </summary>
-        /// <inheritdoc />
+        public Ordered()
-        public void Dither<TColor>(PixelAccessor<TColor> pixels, TColor source, TColor upper, TColor lower, byte[] bytes, int index, int x, int y, int width, int height)
+            : base(ThresholdMatrix)
-            where TColor : struct, IPixel<TColor>
         {
-            source.ToXyzwBytes(bytes, 0);
-            pixels[x, y] = ThresholdMatrix[y % 3, x % 3] >= bytes[index] ? lower : upper;
         }
     }
 }

src/ImageSharp/Dithering/Ordered/OrderedDither4x4.cs

@@ -0,0 +1,38 @@
+// <copyright file="OrderedDither4x4.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageSharp.Dithering.Ordered
+{
+    /// <summary>
+    /// The base class for performing ordered ditheroing using a 4x4 matrix.
+    /// </summary>
+    public abstract class OrderedDither4x4 : IOrderedDither
+    {
+        /// <summary>
+        /// The dithering matrix
+        /// </summary>
+        private Fast2DArray<byte> matrix;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="OrderedDither4x4"/> class.
+        /// </summary>
+        /// <param name="matrix">The thresholding matrix. </param>
+        internal OrderedDither4x4(Fast2DArray<byte> matrix)
+        {
+            this.matrix = matrix;
+        }
+
+        /// <inheritdoc />
+        public void Dither<TColor>(PixelAccessor<TColor> pixels, TColor source, TColor upper, TColor lower, byte[] bytes, int index, int x, int y, int width, int height)
+            where TColor : struct, IPixel<TColor>
+        {
+            // TODO: This doesn't really cut it for me.
+            // I'd rather be using float but we need to add some sort of movalization vector methods to all IPixel implementations
+            // before we can do that as the vectors all cover different ranges.
+            source.ToXyzwBytes(bytes, 0);
+            pixels[x, y] = this.matrix[y % 3, x % 3] >= bytes[index] ? lower : upper;
+        }
+    }
+}

src/ImageSharp/Image/PixelAccessor{TColor}.cs

@@ -148,6 +148,37 @@ namespace ImageSharp
             }
         }
 
+        /// <summary>
+        /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
+        /// </summary>
+        public void Dispose()
+        {
+            if (this.isDisposed)
+            {
+                return;
+            }
+
+            // Note disposing is done.
+            this.isDisposed = true;
+
+            this.pixelBuffer.Dispose();
+
+            // This object will be cleaned up by the Dispose method.
+            // Therefore, you should call GC.SuppressFinalize to
+            // take this object off the finalization queue
+            // and prevent finalization code for this object
+            // from executing a second time.
+            GC.SuppressFinalize(this);
+        }
+
+        /// <summary>
+        /// Resets all the pixels to it's initial value.
+        /// </summary>
+        public void Reset()
+        {
+            Unsafe.InitBlock(this.pixelsBase, 0, (uint)(this.RowStride * this.Height));
+        }
+
         /// <summary>
         /// Copy an area of pixels to the image.
         /// </summary>
@@ -157,7 +188,7 @@ namespace ImageSharp
         /// <exception cref="NotSupportedException">
         /// Thrown when an unsupported component order value is passed.
         /// </exception>
-        public void CopyFrom(PixelArea<TColor> area, int targetY, int targetX = 0)
+        internal void CopyFrom(PixelArea<TColor> area, int targetY, int targetX = 0)
         {
             this.CheckCoordinates(area, targetX, targetY);
 
@@ -173,7 +204,7 @@ namespace ImageSharp
         /// <exception cref="NotSupportedException">
         /// Thrown when an unsupported component order value is passed.
         /// </exception>
-        public void CopyTo(PixelArea<TColor> area, int sourceY, int sourceX = 0)
+        internal void CopyTo(PixelArea<TColor> area, int sourceY, int sourceX = 0)
         {
             this.CheckCoordinates(area, sourceX, sourceY);
 
@@ -190,7 +221,7 @@ namespace ImageSharp
         /// <exception cref="NotSupportedException">
         /// Thrown when an unsupported component order value is passed.
         /// </exception>
-        public void SafeCopyTo(PixelArea<TColor> area, int sourceY, int sourceX = 0)
+        internal void SafeCopyTo(PixelArea<TColor> area, int sourceY, int sourceX = 0)
         {
             int width = Math.Min(area.Width, this.Width - sourceX);
             if (width < 1)
@@ -207,37 +238,6 @@ namespace ImageSharp
             this.CopyTo(area, sourceX, sourceY, width, height);
         }
 
-        /// <summary>
-        /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
-        /// </summary>
-        public void Dispose()
-        {
-            if (this.isDisposed)
-            {
-                return;
-            }
-
-            // Note disposing is done.
-            this.isDisposed = true;
-
-            this.pixelBuffer.Dispose();
-
-            // This object will be cleaned up by the Dispose method.
-            // Therefore, you should call GC.SuppressFinalize to
-            // take this object off the finalization queue
-            // and prevent finalization code for this object
-            // from executing a second time.
-            GC.SuppressFinalize(this);
-        }
-
-        /// <summary>
-        /// Resets all the pixels to it's initial value.
-        /// </summary>
-        public void Reset()
-        {
-            Unsafe.InitBlock(this.pixelsBase, 0, (uint)(this.RowStride * this.Height));
-        }
-
         /// <summary>
         /// Gets a <see cref="BufferPointer{TColor}"/> to the row 'y' beginning from the pixel at 'x'.
         /// </summary>

src/ImageSharp/Image/PixelArea{TColor}.cs

@@ -5,17 +5,15 @@
 namespace ImageSharp
 {
     using System;
-    using System.Buffers;
     using System.Diagnostics;
     using System.IO;
     using System.Runtime.CompilerServices;
-    using System.Runtime.InteropServices;
 
     /// <summary>
     /// Represents an area of generic <see cref="Image{TColor}"/> pixels.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public sealed unsafe class PixelArea<TColor> : IDisposable
+    internal sealed unsafe class PixelArea<TColor> : IDisposable
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/ImageProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing
     /// Allows the application of processors to images.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class ImageProcessor<TColor> : IImageProcessor<TColor>
+    internal abstract class ImageProcessor<TColor> : IImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/ImageSharp.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <Description>A cross-platform library for the processing of image files; written in C#</Description>
     <AssemblyTitle>ImageSharp</AssemblyTitle>
-    <VersionPrefix>1.0.0-alpha3</VersionPrefix>
+    <VersionPrefix>1.0.0-alpha4</VersionPrefix>
     <Authors>James Jackson-South and contributors</Authors>
     <TargetFrameworks>netstandard1.3;netstandard1.1</TargetFrameworks>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>

src/ImageSharp/Processing/Processors/Binarization/BinaryThresholdProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// <see cref="Image"/>. The image will be converted to grayscale before thresholding occurs.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class BinaryThresholdProcessor<TColor> : ImageProcessor<TColor>
+    internal class BinaryThresholdProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Binarization/ErrorDiffusionDitherProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> that dithers an image using error diffusion.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class ErrorDiffusionDitherProcessor<TColor> : ImageProcessor<TColor>
+    internal class ErrorDiffusionDitherProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Binarization/OrderedDitherProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> that dithers an image using error diffusion.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class OrderedDitherProcessor<TColor> : ImageProcessor<TColor>
+    internal class OrderedDitherProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/ColorMatrix/BlackWhiteProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image to their black and white equivalent.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class BlackWhiteProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class BlackWhiteProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/AchromatomalyProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Achromatomaly (Color desensitivity) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class AchromatomalyProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class AchromatomalyProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/AchromatopsiaProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Achromatopsia (Monochrome) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class AchromatopsiaProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class AchromatopsiaProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/DeuteranomalyProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Deuteranomaly (Green-Weak) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class DeuteranomalyProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class DeuteranomalyProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/DeuteranopiaProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Deuteranopia (Green-Blind) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class DeuteranopiaProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class DeuteranopiaProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/ProtanomalyProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Protanopia (Red-Weak) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class ProtanomalyProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class ProtanomalyProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/ProtanopiaProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Protanopia (Red-Blind) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class ProtanopiaProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class ProtanopiaProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/TritanomalyProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Tritanomaly (Blue-Weak) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class TritanomalyProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class TritanomalyProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorBlindness/TritanopiaProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating Tritanopia (Blue-Blind) color blindness.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class TritanopiaProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class TritanopiaProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/ColorMatrixFilter.cs → src/ImageSharp/Processing/Processors/ColorMatrix/ColorMatrixProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// The color matrix filter. Inherit from this class to perform operation involving color matrices.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class ColorMatrixFilter<TColor> : ImageProcessor<TColor>, IColorMatrixFilter<TColor>
+    internal abstract class ColorMatrixProcessor<TColor> : ImageProcessor<TColor>, IColorMatrixFilter<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/GrayscaleBt601Processor.cs

@@ -9,11 +9,11 @@ namespace ImageSharp.Processing.Processors
     using System.Numerics;
 
     /// <summary>
-    /// Converts the colors of the image to Grayscale applying the formula as specified by
+    /// Converts the colors of the image to Grayscale applying the formula as specified by ITU-R Recommendation BT.601
-    /// ITU-R Recommendation BT.601 <see href="https://en.wikipedia.org/wiki/Luma_%28video%29#Rec._601_luma_versus_Rec._709_luma_coefficients"/>.
+    /// <see href="https://en.wikipedia.org/wiki/Luma_%28video%29#Rec._601_luma_versus_Rec._709_luma_coefficients"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class GrayscaleBt601Processor<TColor> : ColorMatrixFilter<TColor>
+    internal class GrayscaleBt601Processor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/GrayscaleBt709Processor.cs

@@ -9,11 +9,11 @@ namespace ImageSharp.Processing.Processors
     using System.Numerics;
 
     /// <summary>
-    /// Converts the colors of the image to Grayscale applying the formula as specified by
+    /// Converts the colors of the image to Grayscale applying the formula as specified by ITU-R Recommendation BT.709
-    /// ITU-R Recommendation BT.709 <see href="https://en.wikipedia.org/wiki/Rec._709#Luma_coefficients"/>.
+    /// <see href="https://en.wikipedia.org/wiki/Rec._709#Luma_coefficients"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class GrayscaleBt709Processor<TColor> : ColorMatrixFilter<TColor>
+    internal class GrayscaleBt709Processor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/HueProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="ImageProcessor{TColor}"/> to change the hue of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class HueProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class HueProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/ColorMatrix/IColorMatrixFilter.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// alter the image pixels.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public interface IColorMatrixFilter<TColor> : IImageProcessor<TColor>
+    internal interface IColorMatrixFilter<TColor> : IImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/ColorMatrix/KodachromeProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating an old Kodachrome camera effect.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class KodachromeProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class KodachromeProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/ColorMatrix/LomographProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating an old Lomograph effect.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class LomographProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class LomographProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         private static readonly TColor VeryDarkGreen = ColorBuilder<TColor>.FromRGBA(0, 10, 0, 255);

src/ImageSharp/Processing/Processors/ColorMatrix/PolaroidProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Converts the colors of the image recreating an old Polaroid effect.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class PolaroidProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class PolaroidProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         private static TColor veryDarkOrange = ColorBuilder<TColor>.FromRGB(102, 34, 0);

src/ImageSharp/Processing/Processors/ColorMatrix/SaturationProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="ImageProcessor{TColor}"/> to change the saturation of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class SaturationProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class SaturationProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/ColorMatrix/SepiaProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// The formula used matches the svg specification. <see href="http://www.w3.org/TR/filter-effects/#sepiaEquivalent"/>
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class SepiaProcessor<TColor> : ColorMatrixFilter<TColor>
+    internal class SepiaProcessor<TColor> : ColorMatrixProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/Convolution/BoxBlurProcessor.cs

@@ -11,7 +11,7 @@ namespace ImageSharp.Processing.Processors
     /// Applies a Box blur sampler to the image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class BoxBlurProcessor<TColor> : ImageProcessor<TColor>
+    internal class BoxBlurProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/Convolution2DProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Defines a sampler that uses two one-dimensional matrices to perform convolution against an image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class Convolution2DProcessor<TColor> : ImageProcessor<TColor>
+    internal class Convolution2DProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/Convolution2PassProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Defines a sampler that uses two one-dimensional matrices to perform two-pass convolution against an image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class Convolution2PassProcessor<TColor> : ImageProcessor<TColor>
+    internal class Convolution2PassProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/ConvolutionProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Defines a sampler that uses a 2 dimensional matrix to perform convolution against an image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class ConvolutionProcessor<TColor> : ImageProcessor<TColor>
+    internal class ConvolutionProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/EdgeDetector2DProcessor.cs

@@ -11,7 +11,7 @@ namespace ImageSharp.Processing.Processors
     /// Defines a sampler that detects edges within an image using two one-dimensional matrices.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class EdgeDetector2DProcessor<TColor> : ImageProcessor<TColor>, IEdgeDetectorProcessor<TColor>
+    internal abstract class EdgeDetector2DProcessor<TColor> : ImageProcessor<TColor>, IEdgeDetectorProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/EdgeDetectorCompassProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Defines a sampler that detects edges within an image using a eight two dimensional matrices.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class EdgeDetectorCompassProcessor<TColor> : ImageProcessor<TColor>, IEdgeDetectorProcessor<TColor>
+    internal abstract class EdgeDetectorCompassProcessor<TColor> : ImageProcessor<TColor>, IEdgeDetectorProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/EdgeDetectorProcessor.cs

@@ -11,7 +11,7 @@ namespace ImageSharp.Processing.Processors
     /// Defines a sampler that detects edges within an image using a single two dimensional matrix.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class EdgeDetectorProcessor<TColor> : ImageProcessor<TColor>, IEdgeDetectorProcessor<TColor>
+    internal abstract class EdgeDetectorProcessor<TColor> : ImageProcessor<TColor>, IEdgeDetectorProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/KayyaliProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class KayyaliProcessor<TColor> : EdgeDetector2DProcessor<TColor>
+    internal class KayyaliProcessor<TColor> : EdgeDetector2DProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/KirschProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class KirschProcessor<TColor> : EdgeDetectorCompassProcessor<TColor>
+    internal class KirschProcessor<TColor> : EdgeDetectorCompassProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/Laplacian3X3Processor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class Laplacian3X3Processor<TColor> : EdgeDetectorProcessor<TColor>
+    internal class Laplacian3X3Processor<TColor> : EdgeDetectorProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/Laplacian5X5Processor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class Laplacian5X5Processor<TColor> : EdgeDetectorProcessor<TColor>
+    internal class Laplacian5X5Processor<TColor> : EdgeDetectorProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/LaplacianOfGaussianProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class LaplacianOfGaussianProcessor<TColor> : EdgeDetectorProcessor<TColor>
+    internal class LaplacianOfGaussianProcessor<TColor> : EdgeDetectorProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/PrewittProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class PrewittProcessor<TColor> : EdgeDetector2DProcessor<TColor>
+    internal class PrewittProcessor<TColor> : EdgeDetector2DProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/RobertsCrossProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class RobertsCrossProcessor<TColor> : EdgeDetector2DProcessor<TColor>
+    internal class RobertsCrossProcessor<TColor> : EdgeDetector2DProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/RobinsonProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class RobinsonProcessor<TColor> : EdgeDetectorCompassProcessor<TColor>
+    internal class RobinsonProcessor<TColor> : EdgeDetectorCompassProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/ScharrProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class ScharrProcessor<TColor> : EdgeDetector2DProcessor<TColor>
+    internal class ScharrProcessor<TColor> : EdgeDetector2DProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/EdgeDetection/SobelProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
     [SuppressMessage("ReSharper", "StaticMemberInGenericType", Justification = "We want to use only one instance of each array field for each generic type.")]
-    public class SobelProcessor<TColor> : EdgeDetector2DProcessor<TColor>
+    internal class SobelProcessor<TColor> : EdgeDetector2DProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/GaussianBlurProcessor.cs

@@ -11,7 +11,7 @@ namespace ImageSharp.Processing.Processors
     /// Applies a Gaussian blur sampler to the image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class GaussianBlurProcessor<TColor> : ImageProcessor<TColor>
+    internal class GaussianBlurProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Convolution/GaussianSharpenProcessor.cs

@@ -11,7 +11,7 @@ namespace ImageSharp.Processing.Processors
     /// Applies a Gaussian sharpening sampler to the image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class GaussianSharpenProcessor<TColor> : ImageProcessor<TColor>
+    internal class GaussianSharpenProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Effects/AlphaProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> to change the alpha component of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class AlphaProcessor<TColor> : ImageProcessor<TColor>
+    internal class AlphaProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Effects/BackgroundColorProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Sets the background color of the image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class BackgroundColorProcessor<TColor> : ImageProcessor<TColor>
+    internal class BackgroundColorProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Effects/BrightnessProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> to change the brightness of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class BrightnessProcessor<TColor> : ImageProcessor<TColor>
+    internal class BrightnessProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Effects/ContrastProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> to change the contrast of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class ContrastProcessor<TColor> : ImageProcessor<TColor>
+    internal class ContrastProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Effects/InvertProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> to invert the colors of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class InvertProcessor<TColor> : ImageProcessor<TColor>
+    internal class InvertProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <inheritdoc/>

src/ImageSharp/Processing/Processors/Effects/OilPaintingProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// </summary>
     /// <remarks>Adapted from <see href="https://softwarebydefault.com/2013/06/29/oil-painting-cartoon-filter/"/> by Dewald Esterhuizen.</remarks>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class OilPaintingProcessor<TColor> : ImageProcessor<TColor>
+    internal class OilPaintingProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Effects/PixelateProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> to pixelate the colors of an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class PixelateProcessor<TColor> : ImageProcessor<TColor>
+    internal class PixelateProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Overlays/GlowProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> that applies a radial glow effect an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class GlowProcessor<TColor> : ImageProcessor<TColor>
+    internal class GlowProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Overlays/VignetteProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// An <see cref="IImageProcessor{TColor}"/> that applies a radial vignette effect to an <see cref="Image{TColor}"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class VignetteProcessor<TColor> : ImageProcessor<TColor>
+    internal class VignetteProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/CompandingResizeProcessor.cs

@@ -14,7 +14,7 @@ namespace ImageSharp.Processing.Processors
     /// This version will expand and compress the image to and from a linear color space during processing.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class CompandingResizeProcessor<TColor> : ResamplingWeightedProcessor<TColor>
+    internal class CompandingResizeProcessor<TColor> : ResamplingWeightedProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/CropProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Provides methods to allow the cropping of an image.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class CropProcessor<TColor> : ImageProcessor<TColor>
+    internal class CropProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/EntropyCropProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// entropy.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class EntropyCropProcessor<TColor> : ImageProcessor<TColor>
+    internal class EntropyCropProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/FlipProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Provides methods that allow the flipping of an image around its center point.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class FlipProcessor<TColor> : ImageProcessor<TColor>
+    internal class FlipProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/Matrix3x2Processor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Provides methods to transform an image using a <see cref="Matrix3x2"/>.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class Matrix3x2Processor<TColor> : ImageProcessor<TColor>
+    internal abstract class Matrix3x2Processor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/ResamplingWeightedProcessor.cs

@@ -12,7 +12,7 @@ namespace ImageSharp.Processing.Processors
     /// Adapted from <see href="http://www.realtimerendering.com/resources/GraphicsGems/gemsiii/filter_rcg.c"/>
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public abstract class ResamplingWeightedProcessor<TColor> : ImageProcessor<TColor>
+    internal abstract class ResamplingWeightedProcessor<TColor> : ImageProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/ResizeProcessor.cs

@@ -16,7 +16,7 @@ namespace ImageSharp.Processing.Processors
     /// This version and the <see cref="CompandingResizeProcessor{TColor}"/> have been separated out to improve performance.
     /// </remarks>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class ResizeProcessor<TColor> : ResamplingWeightedProcessor<TColor>
+    internal class ResizeProcessor<TColor> : ResamplingWeightedProcessor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/RotateProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Provides methods that allow the rotating of images.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class RotateProcessor<TColor> : Matrix3x2Processor<TColor>
+    internal class RotateProcessor<TColor> : Matrix3x2Processor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Processing/Processors/Transforms/SkewProcessor.cs

@@ -13,7 +13,7 @@ namespace ImageSharp.Processing.Processors
     /// Provides methods that allow the skewing of images.
     /// </summary>
     /// <typeparam name="TColor">The pixel format.</typeparam>
-    public class SkewProcessor<TColor> : Matrix3x2Processor<TColor>
+    internal class SkewProcessor<TColor> : Matrix3x2Processor<TColor>
         where TColor : struct, IPixel<TColor>
     {
         /// <summary>

src/ImageSharp/Quantizers/IQuantizer.cs

@@ -5,8 +5,6 @@
 
 namespace ImageSharp.Quantizers
 {
-    using System;
-
     using ImageSharp.Dithering;
 
     /// <summary>

src/ImageSharp/Quantizers/Octree/OctreeQuantizer.cs

@@ -7,6 +7,7 @@ namespace ImageSharp.Quantizers
 {
     using System;
     using System.Collections.Generic;
+    using System.Runtime.CompilerServices;
 
     /// <summary>
     /// Encapsulates methods to calculate the color palette if an image using an Octree pattern.
@@ -16,6 +17,11 @@ namespace ImageSharp.Quantizers
     public sealed class OctreeQuantizer<TColor> : Quantizer<TColor>
         where TColor : struct, IPixel<TColor>
     {
+        /// <summary>
+        /// A lookup table for colors
+        /// </summary>
+        private readonly Dictionary<TColor, byte> colorMap = new Dictionary<TColor, byte>();
+
         /// <summary>
         /// The pixel buffer, used to reduce allocations.
         /// </summary>
@@ -31,6 +37,11 @@ namespace ImageSharp.Quantizers
         /// </summary>
         private int colors;
 
+        /// <summary>
+        /// The reduced image palette
+        /// </summary>
+        private TColor[] palette;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="OctreeQuantizer{TColor}"/> class.
         /// </summary>
@@ -52,6 +63,58 @@ namespace ImageSharp.Quantizers
             return base.Quantize(image, maxColors);
         }
 
+        /// <summary>
+        /// Execute a second pass through the bitmap
+        /// </summary>
+        /// <param name="source">The source image.</param>
+        /// <param name="output">The output pixel array</param>
+        /// <param name="width">The width in pixels of the image</param>
+        /// <param name="height">The height in pixels of the image</param>
+        protected override void SecondPass(PixelAccessor<TColor> source, byte[] output, int width, int height)
+        {
+            // Load up the values for the first pixel. We can use these to speed up the second
+            // pass of the algorithm by avoiding transforming rows of identical color.
+            TColor sourcePixel = source[0, 0];
+            TColor previousPixel = sourcePixel;
+            byte pixelValue = this.QuantizePixel(sourcePixel);
+            TColor[] colorPalette = this.GetPalette();
+            TColor transformedPixel = colorPalette[pixelValue];
+
+            for (int y = 0; y < height; y++)
+            {
+                // And loop through each column
+                for (int x = 0; x < width; x++)
+                {
+                    // Get the pixel.
+                    sourcePixel = source[x, y];
+
+                    // Check if this is the same as the last pixel. If so use that value
+                    // rather than calculating it again. This is an inexpensive optimization.
+                    if (!previousPixel.Equals(sourcePixel))
+                    {
+                        // Quantize the pixel
+                        pixelValue = this.QuantizePixel(sourcePixel);
+
+                        // And setup the previous pointer
+                        previousPixel = sourcePixel;
+
+                        if (this.Dither)
+                        {
+                            transformedPixel = colorPalette[pixelValue];
+                        }
+                    }
+
+                    if (this.Dither)
+                    {
+                        // Apply the dithering matrix. We have to reapply the value now as the original has changed.
+                        this.DitherType.Dither(source, sourcePixel, transformedPixel, x, y, width, height);
+                    }
+
+                    output[(y * source.Width) + x] = pixelValue;
+                }
+            }
+        }
+
         /// <summary>
         /// Process the pixel in the first pass of the algorithm
         /// </summary>
@@ -69,26 +132,39 @@ namespace ImageSharp.Quantizers
         }
 
         /// <summary>
-        /// Override this to process the pixel in the second pass of the algorithm
+        /// Retrieve the palette for the quantized image.
         /// </summary>
-        /// <param name="pixel">The pixel to quantize</param>
         /// <returns>
-        /// The quantized value
+        /// The new color palette
         /// </returns>
-        protected override byte QuantizePixel(TColor pixel)
+        protected override TColor[] GetPalette()
         {
-            return (byte)this.octree.GetPaletteIndex(pixel, this.pixelBuffer);
+            if (this.palette == null)
+            {
+                this.palette = this.octree.Palletize(Math.Max(this.colors, 1));
+            }
+
+            return this.palette;
         }
 
         /// <summary>
-        /// Retrieve the palette for the quantized image.
+        /// Process the pixel in the second pass of the algorithm
         /// </summary>
+        /// <param name="pixel">The pixel to quantize</param>
         /// <returns>
-        /// The new color palette
+        /// The quantized value
         /// </returns>
-        protected override TColor[] GetPalette()
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private byte QuantizePixel(TColor pixel)
         {
-            return this.octree.Palletize(Math.Max(this.colors, 1));
+            if (this.Dither)
+            {
+                // The colors have changed so we need to use Euclidean distance caclulation to find the closest value.
+                // This palette can never be null here.
+                return this.GetClosestColor(pixel, this.palette, this.colorMap);
+            }
+
+            return (byte)this.octree.GetPaletteIndex(pixel, this.pixelBuffer);
         }
 
         /// <summary>

src/ImageSharp/Quantizers/Octree/Quantizer.cs

@@ -9,7 +9,6 @@ namespace ImageSharp.Quantizers
     using System.Collections.Generic;
     using System.Numerics;
     using System.Runtime.CompilerServices;
-
     using ImageSharp.Dithering;
 
     /// <summary>
@@ -19,21 +18,11 @@ namespace ImageSharp.Quantizers
     public abstract class Quantizer<TColor> : IDitheredQuantizer<TColor>
         where TColor : struct, IPixel<TColor>
     {
-        /// <summary>
-        /// A lookup table for colors
-        /// </summary>
-        private readonly Dictionary<TColor, byte> colorMap = new Dictionary<TColor, byte>();
-
         /// <summary>
         /// Flag used to indicate whether a single pass or two passes are needed for quantization.
         /// </summary>
         private readonly bool singlePass;
 
-        /// <summary>
-        /// The reduced image palette
-        /// </summary>
-        private TColor[] palette;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="Quantizer{TColor}"/> class.
         /// </summary>
@@ -65,6 +54,7 @@ namespace ImageSharp.Quantizers
             int height = image.Height;
             int width = image.Width;
             byte[] quantizedPixels = new byte[width * height];
+            TColor[] colorPalette;
 
             using (PixelAccessor<TColor> pixels = image.Lock())
             {
@@ -76,8 +66,8 @@ namespace ImageSharp.Quantizers
                     this.FirstPass(pixels, width, height);
                 }
 
-                // Get the palette
+                // Collect the palette. Octree requires this to be done before the second pass runs.
-                this.palette = this.GetPalette();
+                colorPalette = this.GetPalette();
 
                 if (this.Dither)
                 {
@@ -94,7 +84,7 @@ namespace ImageSharp.Quantizers
                 }
             }
 
-            return new QuantizedImage<TColor>(width, height, this.palette, quantizedPixels);
+            return new QuantizedImage<TColor>(width, height, colorPalette, quantizedPixels);
         }
 
         /// <summary>
@@ -124,25 +114,7 @@ namespace ImageSharp.Quantizers
         /// <param name="output">The output pixel array</param>
         /// <param name="width">The width in pixels of the image</param>
         /// <param name="height">The height in pixels of the image</param>
-        protected virtual void SecondPass(PixelAccessor<TColor> source, byte[] output, int width, int height)
+        protected abstract void SecondPass(PixelAccessor<TColor> source, byte[] output, int width, int height);
-        {
-            for (int y = 0; y < height; y++)
-            {
-                // And loop through each column
-                for (int x = 0; x < width; x++)
-                {
-                    if (this.Dither)
-                    {
-                        // Apply the dithering matrix
-                        TColor sourcePixel = source[x, y];
-                        TColor transformedPixel = this.palette[this.GetClosestColor(sourcePixel, this.palette, this.colorMap)];
-                        this.DitherType.Dither(source, sourcePixel, transformedPixel, x, y, width, height);
-                    }
-
-                    output[(y * source.Width) + x] = this.QuantizePixel(source[x, y]);
-                }
-            }
-        }
 
         /// <summary>
         /// Override this to process the pixel in the first pass of the algorithm
@@ -157,16 +129,7 @@ namespace ImageSharp.Quantizers
         }
 
         /// <summary>
-        /// Override this to process the pixel in the second pass of the algorithm
+        /// Retrieve the palette for the quantized image. Can be called more than once so make sure calls are cached.
-        /// </summary>
-        /// <param name="pixel">The pixel to quantize</param>
-        /// <returns>
-        /// The quantized value
-        /// </returns>
-        protected abstract byte QuantizePixel(TColor pixel);
-
-        /// <summary>
-        /// Retrieve the palette for the quantized image
         /// </summary>
         /// <returns>
         /// <see cref="T:TColor[]"/>
@@ -184,9 +147,9 @@ namespace ImageSharp.Quantizers
         protected byte GetClosestColor(TColor pixel, TColor[] colorPalette, Dictionary<TColor, byte> cache)
         {
             // Check if the color is in the lookup table
-            if (this.colorMap.ContainsKey(pixel))
+            if (cache.ContainsKey(pixel))
             {
-                return this.colorMap[pixel];
+                return cache[pixel];
             }
 
             // Not found - loop through the palette and find the nearest match.
@@ -215,7 +178,7 @@ namespace ImageSharp.Quantizers
             }
 
             // Now I have the index, pop it into the cache for next time
-            this.colorMap.Add(pixel, colorIndex);
+            cache.Add(pixel, colorIndex);
 
             return colorIndex;
         }

src/ImageSharp/Quantizers/Palette/PaletteQuantizer.cs

@@ -7,6 +7,8 @@ namespace ImageSharp.Quantizers
 {
     using System;
     using System.Collections.Generic;
+    using System.Numerics;
+    using System.Runtime.CompilerServices;
 
     /// <summary>
     /// Encapsulates methods to create a quantized image based upon the given palette.
@@ -69,10 +71,56 @@ namespace ImageSharp.Quantizers
             return base.Quantize(image, maxColors);
         }
 
-        /// <inheritdoc/>
+        /// <summary>
-        protected override byte QuantizePixel(TColor pixel)
+        /// Execute a second pass through the bitmap
+        /// </summary>
+        /// <param name="source">The source image.</param>
+        /// <param name="output">The output pixel array</param>
+        /// <param name="width">The width in pixels of the image</param>
+        /// <param name="height">The height in pixels of the image</param>
+        protected override void SecondPass(PixelAccessor<TColor> source, byte[] output, int width, int height)
         {
-            return this.GetClosestColor(pixel, this.colors, this.colorMap);
+            // Load up the values for the first pixel. We can use these to speed up the second
+            // pass of the algorithm by avoiding transforming rows of identical color.
+            TColor sourcePixel = source[0, 0];
+            TColor previousPixel = sourcePixel;
+            byte pixelValue = this.QuantizePixel(sourcePixel);
+            TColor[] colorPalette = this.GetPalette();
+            TColor transformedPixel = colorPalette[pixelValue];
+
+            for (int y = 0; y < height; y++)
+            {
+                // And loop through each column
+                for (int x = 0; x < width; x++)
+                {
+                    // Get the pixel.
+                    sourcePixel = source[x, y];
+
+                    // Check if this is the same as the last pixel. If so use that value
+                    // rather than calculating it again. This is an inexpensive optimization.
+                    if (!previousPixel.Equals(sourcePixel))
+                    {
+                        // Quantize the pixel
+                        pixelValue = this.QuantizePixel(sourcePixel);
+
+                        // And setup the previous pointer
+                        previousPixel = sourcePixel;
+
+                        if (this.Dither)
+                        {
+                            transformedPixel = colorPalette[pixelValue];
+                        }
+                    }
+
+                    if (this.Dither)
+                    {
+                        // Apply the dithering matrix. We have to reapply the value now as the original has changed.
+                        this.DitherType.Dither(source, sourcePixel, transformedPixel, x, y, width, height);
+                    }
+
+                    output[(y * source.Width) + x] = pixelValue;
+                }
+            }
         }
 
         /// <inheritdoc/>
@@ -80,5 +128,18 @@ namespace ImageSharp.Quantizers
         {
             return this.colors;
         }
+
+        /// <summary>
+        /// Process the pixel in the second pass of the algorithm
+        /// </summary>
+        /// <param name="pixel">The pixel to quantize</param>
+        /// <returns>
+        /// The quantized value
+        /// </returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private byte QuantizePixel(TColor pixel)
+        {
+            return this.GetClosestColor(pixel, this.GetPalette(), this.colorMap);
+        }
     }
 }