Sampler performance optimizations

Former-commit-id: 57f9665225227b25a9dc53357985097001df37c8
Former-commit-id: 0ba692a70a1480b5de88015bb0660a2471f63ec3
Former-commit-id: 055257264bc4063a23db7c056a7cfa7a7c4394be

src/ImageProcessorCore/Samplers/Processors/EntropyCropProcessor.cs

@@ -24,7 +24,7 @@ namespace ImageProcessorCore.Processors
         private Rectangle cropRectangle;
 
         /// <summary>
-        /// Initializes a new instance of the <see cref="EntropyCropProcessor"/> class.
+        /// Initializes a new instance of the <see cref="EntropyCropProcessor{T,TP}"/> class.
         /// </summary>
         /// <param name="threshold">The threshold to split the image. Must be between 0 and 1.</param>
         /// <exception cref="ArgumentException">
@@ -74,21 +74,21 @@ namespace ImageProcessorCore.Processors
             int startX = this.cropRectangle.X;
             int endX = this.cropRectangle.Right;
 
+            int minY = Math.Max(targetY, startY);
+            int maxY = Math.Min(targetBottom, endY);
+
             using (IPixelAccessor<T, TP> sourcePixels = source.Lock())
             using (IPixelAccessor<T, TP> targetPixels = target.Lock())
             {
                 Parallel.For(
-                    startY,
-                    endY,
+                    minY,
+                    maxY,
                     this.ParallelOptions,
                     y =>
                         {
-                            if (y >= targetY && y < targetBottom)
+                            for (int x = startX; x < endX; x++)
                             {
-                                for (int x = startX; x < endX; x++)
-                                {
-                                    targetPixels[x - startX, y - targetY] = sourcePixels[x, y];
-                                }
+                                targetPixels[x - startX, y - targetY] = sourcePixels[x, y];
                             }
 
                             this.OnRowProcessed();

src/ImageProcessorCore/Samplers/Processors/Matrix3x2Processor.cs

@@ -19,8 +19,6 @@ namespace ImageProcessorCore.Processors
         /// <summary>
         /// Creates a new target to contain the results of the matrix transform.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">Target image to apply the process to.</param>
         /// <param name="sourceRectangle">The source rectangle.</param>
         /// <param name="processMatrix">The processing matrix.</param>
@@ -37,8 +35,6 @@ namespace ImageProcessorCore.Processors
         /// <summary>
         /// Gets a transform matrix adjusted to center upon the target image bounds.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">Target image to apply the process to.</param>
         /// <param name="source">The source image.</param>
         /// <param name="matrix">The transform matrix.</param>
@@ -47,8 +43,8 @@ namespace ImageProcessorCore.Processors
         /// </returns>
         protected static Matrix3x2 GetCenteredMatrix(ImageBase<T, TP> target, ImageBase<T, TP> source, Matrix3x2 matrix)
         {
-            Matrix3x2 translationToTargetCenter = Matrix3x2.CreateTranslation(-target.Width / 2f, -target.Height / 2f);
-            Matrix3x2 translateToSourceCenter = Matrix3x2.CreateTranslation(source.Width / 2f, source.Height / 2f);
+            Matrix3x2 translationToTargetCenter = Matrix3x2.CreateTranslation(-target.Width * .5F, -target.Height * .5F);
+            Matrix3x2 translateToSourceCenter = Matrix3x2.CreateTranslation(source.Width * .5F, source.Height * .5F);
             return (translationToTargetCenter * matrix) * translateToSourceCenter;
         }
     }

src/ImageProcessorCore/Samplers/Processors/RotateFlipProcessor.cs

@@ -18,7 +18,7 @@ namespace ImageProcessorCore.Processors
         where TP : struct
     {
         /// <summary>
-        /// Initializes a new instance of the <see cref="RotateFlipProcessor"/> class.
+        /// Initializes a new instance of the <see cref="RotateFlipProcessor{T,TP}"/> class.
         /// </summary>
         /// <param name="rotateType">The <see cref="RotateType"/> used to perform rotation.</param>
         /// <param name="flipType">The <see cref="FlipType"/> used to perform flipping.</param>
@@ -72,8 +72,6 @@ namespace ImageProcessorCore.Processors
         /// <summary>
         /// Rotates the image 270 degrees clockwise at the centre point.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">The target image.</param>
         /// <param name="source">The source image.</param>
         private void Rotate270(ImageBase<T, TP> target, ImageBase<T, TP> source)
@@ -110,8 +108,6 @@ namespace ImageProcessorCore.Processors
         /// <summary>
         /// Rotates the image 180 degrees clockwise at the centre point.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">The target image.</param>
         /// <param name="source">The source image.</param>
         private void Rotate180(ImageBase<T, TP> target, ImageBase<T, TP> source)
@@ -143,8 +139,6 @@ namespace ImageProcessorCore.Processors
         /// <summary>
         /// Rotates the image 90 degrees clockwise at the centre point.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">The target image.</param>
         /// <param name="source">The source image.</param>
         private void Rotate90(ImageBase<T, TP> target, ImageBase<T, TP> source)
@@ -179,14 +173,12 @@ namespace ImageProcessorCore.Processors
         /// Swaps the image at the X-axis, which goes horizontally through the middle
         /// at half the height of the image.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">Target image to apply the process to.</param>
         private void FlipX(ImageBase<T, TP> target)
         {
             int width = target.Width;
             int height = target.Height;
-            int halfHeight = (int)Math.Ceiling(target.Height * .5);
+            int halfHeight = (int)Math.Ceiling(target.Height * .5F);
             Image<T, TP> temp = new Image<T, TP>(width, height);
             temp.ClonePixels(width, height, target.Pixels);
 
@@ -215,14 +207,12 @@ namespace ImageProcessorCore.Processors
         /// Swaps the image at the Y-axis, which goes vertically through the middle
         /// at half of the width of the image.
         /// </summary>
-        /// <typeparam name="T">The pixel format.</typeparam>
-        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
         /// <param name="target">Target image to apply the process to.</param>
         private void FlipY(ImageBase<T, TP> target)
         {
             int width = target.Width;
             int height = target.Height;
-            int halfWidth = (int)Math.Ceiling(width / 2d);
+            int halfWidth = (int)Math.Ceiling(width * .5F);
             Image<T, TP> temp = new Image<T, TP>(width, height);
             temp.ClonePixels(width, height, target.Pixels);
 

src/ImageProcessorCore/Samplers/Processors/RotateProcessor.cs

@@ -2,7 +2,6 @@
 // Copyright (c) James Jackson-South and contributors.
 // Licensed under the Apache License, Version 2.0.
 // </copyright>
-
 namespace ImageProcessorCore.Processors
 {
     using System.Numerics;
@@ -35,16 +34,18 @@ namespace ImageProcessorCore.Processors
         /// <inheritdoc/>
         protected override void OnApply(ImageBase<T, TP> target, ImageBase<T, TP> source, Rectangle targetRectangle, Rectangle sourceRectangle)
         {
-            processMatrix = Point.CreateRotation(new Point(0, 0), -this.Angle);
+            this.processMatrix = Point.CreateRotation(new Point(0, 0), -this.Angle);
             if (this.Expand)
             {
-                CreateNewTarget(target, sourceRectangle, processMatrix);
+                CreateNewTarget(target, sourceRectangle, this.processMatrix);
             }
         }
 
         /// <inheritdoc/>
         protected override void Apply(ImageBase<T, TP> target, ImageBase<T, TP> source, Rectangle targetRectangle, Rectangle sourceRectangle, int startY, int endY)
         {
+            int height = target.Height;
+            int width = target.Width;
             Matrix3x2 matrix = GetCenteredMatrix(target, source, this.processMatrix);
 
             using (IPixelAccessor<T, TP> sourcePixels = source.Lock())
@@ -52,11 +53,11 @@ namespace ImageProcessorCore.Processors
             {
                 Parallel.For(
                     0,
-                    target.Height,
+                    height,
                     this.ParallelOptions,
                     y =>
                     {
-                        for (int x = 0; x < target.Width; x++)
+                        for (int x = 0; x < width; x++)
                         {
                             Point transformedPoint = Point.Rotate(new Point(x, y), matrix);
                             if (source.Bounds.Contains(transformedPoint.X, transformedPoint.Y))
@@ -65,7 +66,7 @@ namespace ImageProcessorCore.Processors
                             }
                         }
 
-                        OnRowProcessed();
+                        this.OnRowProcessed();
                     });
             }
         }

src/ImageProcessorCore/Samplers/Processors/SkewProcessor.cs

@@ -50,6 +50,8 @@ namespace ImageProcessorCore.Processors
         /// <inheritdoc/>
         protected override void Apply(ImageBase<T, TP> target, ImageBase<T, TP> source, Rectangle targetRectangle, Rectangle sourceRectangle, int startY, int endY)
         {
+            int height = target.Height;
+            int width = target.Width;
             Matrix3x2 matrix = GetCenteredMatrix(target, source, this.processMatrix);
 
             using (IPixelAccessor<T, TP> sourcePixels = source.Lock())
@@ -57,11 +59,11 @@ namespace ImageProcessorCore.Processors
             {
                 Parallel.For(
                     0,
-                    target.Height,
+                    height,
                     this.ParallelOptions,
                     y =>
                         {
-                            for (int x = 0; x < target.Width; x++)
+                            for (int x = 0; x < width; x++)
                             {
                                 Point transformedPoint = Point.Skew(new Point(x, y), matrix);
                                 if (source.Bounds.Contains(transformedPoint.X, transformedPoint.Y))