From a3c1d1302f9fa9ca86f4b4d2dbecc02b25d9f260 Mon Sep 17 00:00:00 2001
From: James Jackson-South <james_south@hotmail.com>
Date: Thu, 28 Jul 2016 13:29:01 +1000
Subject: [PATCH] Hue, Brightness

Former-commit-id: 390a36f397e55d0caeaca4d5353be432da1c96b9
Former-commit-id: a802e31bbbfe18164aa7f17b057bcf69d3f495b3
Former-commit-id: 6275da035cee61d2d7abf1da32acc7db5f6aae2d
---
 src/ImageProcessorCore/Filters/Brightness.cs  | 60 +++++++++++++++
 src/ImageProcessorCore/Filters/Hue.cs         | 60 +++++++++++++++
 .../Filters/Processors/BrightnessProcessor.cs | 77 +++++++++++++++++++
 src/ImageProcessorCore/Filters/Saturation.cs  |  2 +-
 .../Processors/Filters/BrightnessTest.cs      | 47 +++++++++++
 .../Processors/Filters/HueTest.cs             | 47 +++++++++++
 6 files changed, 292 insertions(+), 1 deletion(-)
 create mode 100644 src/ImageProcessorCore/Filters/Brightness.cs
 create mode 100644 src/ImageProcessorCore/Filters/Hue.cs
 create mode 100644 src/ImageProcessorCore/Filters/Processors/BrightnessProcessor.cs
 create mode 100644 tests/ImageProcessorCore.Tests/Processors/Filters/BrightnessTest.cs
 create mode 100644 tests/ImageProcessorCore.Tests/Processors/Filters/HueTest.cs

diff --git a/src/ImageProcessorCore/Filters/Brightness.cs b/src/ImageProcessorCore/Filters/Brightness.cs
new file mode 100644
index 000000000..fb29ff0d9
--- /dev/null
+++ b/src/ImageProcessorCore/Filters/Brightness.cs
@@ -0,0 +1,60 @@
+// <copyright file="Brightness.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageProcessorCore
+{
+    using Processors;
+
+    /// <summary>
+    /// Extension methods for the <see cref="Image{T,TP}"/> type.
+    /// </summary>
+    public static partial class ImageExtensions
+    {
+        /// <summary>
+        /// Alters the brightness component of the image.
+        /// </summary>
+        /// <typeparam name="T">The pixel format.</typeparam>
+        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
+        /// <param name="source">The image this method extends.</param>
+        /// <param name="amount">The new brightness of the image. Must be between -100 and 100.</param>
+        /// <param name="progressHandler">A delegate which is called as progress is made processing the image.</param>
+        /// <returns>The <see cref="Image{T,TP}"/>.</returns>
+        public static Image<T, TP> Brightness<T, TP>(this Image<T, TP> source, int amount, ProgressEventHandler progressHandler = null)
+            where T : IPackedVector<TP>
+            where TP : struct
+        {
+            return Brightness(source, amount, source.Bounds, progressHandler);
+        }
+
+        /// <summary>
+        /// Alters the brightness component of the image.
+        /// </summary>
+        /// <typeparam name="T">The pixel format.</typeparam>
+        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
+        /// <param name="source">The image this method extends.</param>
+        /// <param name="amount">The new brightness of the image. Must be between -100 and 100.</param>
+        /// <param name="rectangle">
+        /// The <see cref="Rectangle"/> structure that specifies the portion of the image object to alter.
+        /// </param>
+        /// <param name="progressHandler">A delegate which is called as progress is made processing the image.</param>
+        /// <returns>The <see cref="Image{T,TP}"/>.</returns>
+        public static Image<T, TP> Brightness<T, TP>(this Image<T, TP> source, int amount, Rectangle rectangle, ProgressEventHandler progressHandler = null)
+            where T : IPackedVector<TP>
+            where TP : struct
+        {
+            BrightnessProcessor<T, TP> processor = new BrightnessProcessor<T, TP>(amount);
+            processor.OnProgress += progressHandler;
+
+            try
+            {
+                return source.Process(rectangle, processor);
+            }
+            finally
+            {
+                processor.OnProgress -= progressHandler;
+            }
+        }
+    }
+}
diff --git a/src/ImageProcessorCore/Filters/Hue.cs b/src/ImageProcessorCore/Filters/Hue.cs
new file mode 100644
index 000000000..a4de7c610
--- /dev/null
+++ b/src/ImageProcessorCore/Filters/Hue.cs
@@ -0,0 +1,60 @@
+// <copyright file="Hue.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageProcessorCore
+{
+    using Processors;
+
+    /// <summary>
+    /// Extension methods for the <see cref="Image{T,TP}"/> type.
+    /// </summary>
+    public static partial class ImageExtensions
+    {
+        /// <summary>
+        /// Alters the hue component of the image.
+        /// </summary>
+        /// <typeparam name="T">The pixel format.</typeparam>
+        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
+        /// <param name="source">The image this method extends.</param>
+        /// <param name="degrees">The angle in degrees to adjust the image.</param>
+        /// <param name="progressHandler">A delegate which is called as progress is made processing the image.</param>
+        /// <returns>The <see cref="Image{T,TP}"/>.</returns>
+        public static Image<T, TP> Hue<T, TP>(this Image<T, TP> source, float degrees, ProgressEventHandler progressHandler = null)
+            where T : IPackedVector<TP>
+            where TP : struct
+        {
+            return Hue(source, degrees, source.Bounds, progressHandler);
+        }
+
+        /// <summary>
+        /// Alters the hue component of the image.
+        /// </summary>
+        /// <typeparam name="T">The pixel format.</typeparam>
+        /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
+        /// <param name="source">The image this method extends.</param>
+        /// <param name="degrees">The angle in degrees to adjust the image.</param>
+        /// <param name="rectangle">
+        /// The <see cref="Rectangle"/> structure that specifies the portion of the image object to alter.
+        /// </param>
+        /// <param name="progressHandler">A delegate which is called as progress is made processing the image.</param>
+        /// <returns>The <see cref="Image{T,TP}"/>.</returns>
+        public static Image<T, TP> Hue<T, TP>(this Image<T, TP> source, float degrees, Rectangle rectangle, ProgressEventHandler progressHandler = null)
+            where T : IPackedVector<TP>
+            where TP : struct
+        {
+            HueProcessor<T, TP> processor = new HueProcessor<T, TP>(degrees);
+            processor.OnProgress += progressHandler;
+
+            try
+            {
+                return source.Process(rectangle, processor);
+            }
+            finally
+            {
+                processor.OnProgress -= progressHandler;
+            }
+        }
+    }
+}
diff --git a/src/ImageProcessorCore/Filters/Processors/BrightnessProcessor.cs b/src/ImageProcessorCore/Filters/Processors/BrightnessProcessor.cs
new file mode 100644
index 000000000..d253c4ebf
--- /dev/null
+++ b/src/ImageProcessorCore/Filters/Processors/BrightnessProcessor.cs
@@ -0,0 +1,77 @@
+// <copyright file="BrightnessProcessor.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageProcessorCore.Processors
+{
+    using System.Numerics;
+    using System.Threading.Tasks;
+
+    /// <summary>
+    /// An <see cref="IImageProcessor"/> to change the brightness of an <see cref="Image"/>.
+    /// </summary>
+    /// <typeparam name="T">The pixel format.</typeparam>
+    /// <typeparam name="TP">The packed format. <example>long, float.</example></typeparam>
+    public class BrightnessProcessor<T, TP> : ImageProcessor<T, TP>
+        where T : IPackedVector<TP>
+        where TP : struct
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="BrightnessProcessor"/> class.
+        /// </summary>
+        /// <param name="brightness">The new brightness of the image. Must be between -100 and 100.</param>
+        /// <exception cref="ArgumentException">
+        /// <paramref name="brightness"/> is less than -100 or is greater than 100.
+        /// </exception>
+        public BrightnessProcessor(int brightness)
+        {
+            Guard.MustBeBetweenOrEqualTo(brightness, -100, 100, nameof(brightness));
+            this.Value = brightness;
+        }
+
+        /// <summary>
+        /// Gets the brightness value.
+        /// </summary>
+        public int Value { get; }
+
+        /// <inheritdoc/>
+        protected override void Apply(ImageBase<T, TP> target, ImageBase<T, TP> source, Rectangle targetRectangle, Rectangle sourceRectangle, int startY, int endY)
+        {
+            float brightness = this.Value / 100f;
+            int sourceY = sourceRectangle.Y;
+            int sourceBottom = sourceRectangle.Bottom;
+            int startX = sourceRectangle.X;
+            int endX = sourceRectangle.Right;
+
+            using (IPixelAccessor<T, TP> sourcePixels = source.Lock())
+            using (IPixelAccessor<T, TP> targetPixels = target.Lock())
+            {
+                Parallel.For(
+                    startY,
+                    endY,
+                    y =>
+                        {
+                            if (y >= sourceY && y < sourceBottom)
+                            {
+                                for (int x = startX; x < endX; x++)
+                                {
+                                    // TODO: Check this with other formats.
+                                    Vector4 vector = sourcePixels[x, y].ToVector4().Expand();
+                                    Vector3 transformed = new Vector3(vector.X, vector.Y, vector.Z);
+                                    transformed += new Vector3(brightness);
+                                    vector = new Vector4(transformed.X, transformed.Y, transformed.Z, vector.W);
+
+                                    T packed = default(T);
+                                    packed.PackVector(vector.Compress());
+
+                                    targetPixels[x, y] = packed;
+                                }
+
+                                this.OnRowProcessed();
+                            }
+                        });
+            }
+        }
+    }
+}
diff --git a/src/ImageProcessorCore/Filters/Saturation.cs b/src/ImageProcessorCore/Filters/Saturation.cs
index 3c39d4e5c..cdd2a1bc0 100644
--- a/src/ImageProcessorCore/Filters/Saturation.cs
+++ b/src/ImageProcessorCore/Filters/Saturation.cs
@@ -1,7 +1,7 @@
 // <copyright file="Saturation.cs" company="James Jackson-South">
 // Copyright (c) James Jackson-South and contributors.
 // Licensed under the Apache License, Version 2.0.
-// </copyright>-------------------------------------------------------------------------------------------------------------------
+// </copyright>
 
 namespace ImageProcessorCore
 {
diff --git a/tests/ImageProcessorCore.Tests/Processors/Filters/BrightnessTest.cs b/tests/ImageProcessorCore.Tests/Processors/Filters/BrightnessTest.cs
new file mode 100644
index 000000000..9c0d840df
--- /dev/null
+++ b/tests/ImageProcessorCore.Tests/Processors/Filters/BrightnessTest.cs
@@ -0,0 +1,47 @@
+// <copyright file="BrightnessTest.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageProcessorCore.Tests
+{
+    using System.IO;
+
+    using Xunit;
+
+    public class BrightnessTest : FileTestBase
+    {
+        public static readonly TheoryData<int> BrightnessValues
+        = new TheoryData<int>
+        {
+            50 ,
+           -50 ,
+        };
+
+        [Theory]
+        [MemberData("BrightnessValues")]
+        public void ImageShouldApplyBrightnessFilter(int value)
+        {
+            const string path = "TestOutput/Brightness";
+            if (!Directory.Exists(path))
+            {
+                Directory.CreateDirectory(path);
+            }
+
+            foreach (string file in Files)
+            {
+                using (FileStream stream = File.OpenRead(file))
+                {
+                    string filename = Path.GetFileNameWithoutExtension(file) + "-" + value + Path.GetExtension(file);
+
+                    Image image = new Image(stream);
+                    using (FileStream output = File.OpenWrite($"{path}/{filename}"))
+                    {
+                        image.Brightness(value)
+                             .Save(output);
+                    }
+                }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/tests/ImageProcessorCore.Tests/Processors/Filters/HueTest.cs b/tests/ImageProcessorCore.Tests/Processors/Filters/HueTest.cs
new file mode 100644
index 000000000..7ece88159
--- /dev/null
+++ b/tests/ImageProcessorCore.Tests/Processors/Filters/HueTest.cs
@@ -0,0 +1,47 @@
+// <copyright file="HueTest.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageProcessorCore.Tests
+{
+    using System.IO;
+
+    using Xunit;
+
+    public class HueTest : FileTestBase
+    {
+        public static readonly TheoryData<int> HueValues
+        = new TheoryData<int>
+        {
+            180 ,
+           -180 ,
+        };
+
+        [Theory]
+        [MemberData("HueValues")]
+        public void ImageShouldApplyHueFilter(int value)
+        {
+            const string path = "TestOutput/Hue";
+            if (!Directory.Exists(path))
+            {
+                Directory.CreateDirectory(path);
+            }
+
+            foreach (string file in Files)
+            {
+                using (FileStream stream = File.OpenRead(file))
+                {
+                    string filename = Path.GetFileNameWithoutExtension(file) + "-" + value + Path.GetExtension(file);
+
+                    Image image = new Image(stream);
+                    using (FileStream output = File.OpenWrite($"{path}/{filename}"))
+                    {
+                        image.Hue(value)
+                             .Save(output);
+                    }
+                }
+            }
+        }
+    }
+}
\ No newline at end of file