Merge branch 'main' into issue-exif-null-array-value

Author: brianpopow

.github/ISSUE_TEMPLATE/config.yml

@@ -1,5 +1,5 @@
 blank_issues_enabled: false
 contact_links:
     - name: Feature Request
-      url: https://github.com/SixLabors/ImageSharp/discussions?discussions_q=category%3AIdeas
+      url: https://github.com/SixLabors/ImageSharp/discussions/categories/ideas
       about: Share ideas for new features for this project.

README.md

@@ -26,7 +26,7 @@ Built against [.NET Standard 2.0](https://docs.microsoft.com/en-us/dotnet/standa
 ## License
 
 - ImageSharp is licensed under the [Apache License, Version 2.0](https://opensource.org/licenses/Apache-2.0)  
-- An alternative Commercial Support License can be purchased **for projects and applications requiring support**.
+- An alternative Six Labors License can be purchased **for projects and applications requiring developer support**.
 Please visit https://sixlabors.com/pricing for details.
 
 ## Support Six Labors
@@ -43,7 +43,8 @@ Support the efforts of the development of the Six Labors projects.
 
 ## Questions
 
-- Do you have questions? We are happy to help! Please [join our Discussions Forum](https://github.com/SixLabors/ImageSharp/discussions/category_choices), or ask them on [Stack Overflow](https://stackoverflow.com) using the `ImageSharp` tag. Please do not open issues for questions.
+- Do you have questions? We are happy to help! Simply purchase a [Six Labors License](https://sixlabors.com/pricing) for developer support. Please do not open issues for questions or misuse our [Discussions Forum](https://github.com/SixLabors/ImageSharp/discussions).
+- For feature ideas please [join our Discussions Forum](https://github.com/SixLabors/ImageSharp/discussions/categories/ideas) and we'll be happy to discuss.  
 - Please read our [Contribution Guide](https://github.com/SixLabors/ImageSharp/blob/main/.github/CONTRIBUTING.md) before opening issues or pull requests!
 
 ## Code of Conduct  

src/ImageSharp/Formats/Jpeg/Components/Encoder/LuminanceForwardConverter{TPixel}.cs

@@ -2,8 +2,13 @@
 // Licensed under the Apache License, Version 2.0.
 
 using System;
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+#if SUPPORTS_RUNTIME_INTRINSICS
+using System.Runtime.Intrinsics;
+using System.Runtime.Intrinsics.X86;
+#endif
 using SixLabors.ImageSharp.Advanced;
 using SixLabors.ImageSharp.PixelFormats;
 
@@ -74,6 +79,44 @@ public void Convert(int x, int y, ref RowOctet<TPixel> currentRows)
             ref Block8x8F yBlock = ref this.Y;
             ref L8 l8Start = ref MemoryMarshal.GetReference(this.l8Span);
 
+            if (RgbToYCbCrConverterVectorized.IsSupported)
+            {
+                ConvertAvx(ref l8Start, ref yBlock);
+            }
+            else
+            {
+                ConvertScalar(ref l8Start, ref yBlock);
+            }
+        }
+
+        /// <summary>
+        /// Converts 8x8 L8 pixel matrix to 8x8 Block of floats using Avx2 Intrinsics.
+        /// </summary>
+        /// <param name="l8Start">Start of span of L8 pixels with size of 64</param>
+        /// <param name="yBlock">8x8 destination matrix of Luminance(Y) converted data</param>
+        private static void ConvertAvx(ref L8 l8Start, ref Block8x8F yBlock)
+        {
+            Debug.Assert(RgbToYCbCrConverterVectorized.IsSupported, "AVX2 is required to run this converter");
+
+#if SUPPORTS_RUNTIME_INTRINSICS
+            ref Vector128<byte> l8ByteSpan = ref Unsafe.As<L8, Vector128<byte>>(ref l8Start);
+            ref Vector256<float> destRef = ref yBlock.V0;
+
+            const int bytesPerL8Stride = 8;
+            for (nint i = 0; i < 8; i++)
+            {
+                Unsafe.Add(ref destRef, i) = Avx2.ConvertToVector256Single(Avx2.ConvertToVector256Int32(Unsafe.AddByteOffset(ref l8ByteSpan, bytesPerL8Stride * i)));
+            }
+#endif
+        }
+
+        /// <summary>
+        /// Converts 8x8 L8 pixel matrix to 8x8 Block of floats.
+        /// </summary>
+        /// <param name="l8Start">Start of span of L8 pixels with size of 64</param>
+        /// <param name="yBlock">8x8 destination matrix of Luminance(Y) converted data</param>
+        private static void ConvertScalar(ref L8 l8Start, ref Block8x8F yBlock)
+        {
             for (int i = 0; i < Block8x8F.Size; i++)
             {
                 ref L8 c = ref Unsafe.Add(ref l8Start, i);

src/ImageSharp/Formats/Jpeg/Components/Encoder/RgbForwardConverter{TPixel}.cs

@@ -2,8 +2,13 @@
 // Licensed under the Apache License, Version 2.0.
 
 using System;
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+#if SUPPORTS_RUNTIME_INTRINSICS
+using System.Runtime.Intrinsics;
+using System.Runtime.Intrinsics.X86;
+#endif
 using SixLabors.ImageSharp.Advanced;
 using SixLabors.ImageSharp.PixelFormats;
 
@@ -94,10 +99,56 @@ public void Convert(int x, int y, ref RowOctet<TPixel> currentRows)
             ref Block8x8F greenBlock = ref this.G;
             ref Block8x8F blueBlock = ref this.B;
 
-            CopyToBlock(this.rgbSpan, ref redBlock, ref greenBlock, ref blueBlock);
+            if (RgbToYCbCrConverterVectorized.IsSupported)
+            {
+                ConvertAvx(this.rgbSpan, ref redBlock, ref greenBlock, ref blueBlock);
+            }
+            else
+            {
+                ConvertScalar(this.rgbSpan, ref redBlock, ref greenBlock, ref blueBlock);
+            }
+        }
+
+        /// <summary>
+        /// Converts 8x8 RGB24 pixel matrix to 8x8 Block of floats using Avx2 Intrinsics.
+        /// </summary>
+        /// <param name="rgbSpan">Span of Rgb24 pixels with size of 64</param>
+        /// <param name="rBlock">8x8 destination matrix of Red converted data</param>
+        /// <param name="gBlock">8x8 destination matrix of Blue converted data</param>
+        /// <param name="bBlock">8x8 destination matrix of Green converted data</param>
+        private static void ConvertAvx(Span<Rgb24> rgbSpan, ref Block8x8F rBlock, ref Block8x8F gBlock, ref Block8x8F bBlock)
+        {
+            Debug.Assert(RgbToYCbCrConverterVectorized.IsSupported, "AVX2 is required to run this converter");
+
+#if SUPPORTS_RUNTIME_INTRINSICS
+            ref Vector256<byte> rgbByteSpan = ref Unsafe.As<Rgb24, Vector256<byte>>(ref MemoryMarshal.GetReference(rgbSpan));
+            ref Vector256<float> redRef = ref rBlock.V0;
+            ref Vector256<float> greenRef = ref gBlock.V0;
+            ref Vector256<float> blueRef = ref bBlock.V0;
+            var zero = Vector256.Create(0).AsByte();
+
+            var extractToLanesMask = Unsafe.As<byte, Vector256<uint>>(ref MemoryMarshal.GetReference(RgbToYCbCrConverterVectorized.MoveFirst24BytesToSeparateLanes));
+            var extractRgbMask = Unsafe.As<byte, Vector256<byte>>(ref MemoryMarshal.GetReference(RgbToYCbCrConverterVectorized.ExtractRgb));
+            Vector256<byte> rgb, rg, bx;
+
+            const int bytesPerRgbStride = 24;
+            for (nint i = 0; i < 8; i++)
+            {
+                rgb = Avx2.PermuteVar8x32(Unsafe.AddByteOffset(ref rgbByteSpan, bytesPerRgbStride * i).AsUInt32(), extractToLanesMask).AsByte();
+
+                rgb = Avx2.Shuffle(rgb, extractRgbMask);
+
+                rg = Avx2.UnpackLow(rgb, zero);
+                bx = Avx2.UnpackHigh(rgb, zero);
+
+                Unsafe.Add(ref redRef, i) = Avx.ConvertToVector256Single(Avx2.UnpackLow(rg, zero).AsInt32());
+                Unsafe.Add(ref greenRef, i) = Avx.ConvertToVector256Single(Avx2.UnpackHigh(rg, zero).AsInt32());
+                Unsafe.Add(ref blueRef, i) = Avx.ConvertToVector256Single(Avx2.UnpackLow(bx, zero).AsInt32());
+            }
+#endif
         }
 
-        private static void CopyToBlock(Span<Rgb24> rgbSpan, ref Block8x8F redBlock, ref Block8x8F greenBlock, ref Block8x8F blueBlock)
+        private static void ConvertScalar(Span<Rgb24> rgbSpan, ref Block8x8F redBlock, ref Block8x8F greenBlock, ref Block8x8F blueBlock)
         {
             ref Rgb24 rgbStart = ref MemoryMarshal.GetReference(rgbSpan);
 

src/ImageSharp/Formats/Jpeg/Components/Encoder/RgbToYCbCrConverterVectorized.cs

@@ -60,13 +60,13 @@ public static int AvxCompatibilityPadding
 
 #if SUPPORTS_RUNTIME_INTRINSICS
 
-        private static ReadOnlySpan<byte> MoveFirst24BytesToSeparateLanes => new byte[]
+        internal static ReadOnlySpan<byte> MoveFirst24BytesToSeparateLanes => new byte[]
         {
             0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 6, 0, 0, 0,
             3, 0, 0, 0, 4, 0, 0, 0, 5, 0, 0, 0, 7, 0, 0, 0
         };
 
-        private static ReadOnlySpan<byte> ExtractRgb => new byte[]
+        internal static ReadOnlySpan<byte> ExtractRgb => new byte[]
         {
             0, 3, 6, 9, 1, 4, 7, 10, 2, 5, 8, 11, 0xFF, 0xFF, 0xFF, 0xFF,
             0, 3, 6, 9, 1, 4, 7, 10, 2, 5, 8, 11, 0xFF, 0xFF, 0xFF, 0xFF