Decode Jpegs to non-contiguous buffers

src/ImageSharp/ImageFrame{TPixel}.cs

@@ -133,7 +133,7 @@ namespace SixLabors.ImageSharp
             Guard.NotNull(source, nameof(source));
 
             this.PixelBuffer = this.GetConfiguration().MemoryAllocator.Allocate2D<TPixel>(source.PixelBuffer.Width, source.PixelBuffer.Height);
-            source.PixelBuffer.GetSingleSpan().CopyTo(this.PixelBuffer.GetSingleSpan());
+            source.PixelBuffer.MemoryGroup.CopyTo(this.PixelBuffer.MemoryGroup);
         }
 
         /// <summary>

tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Baseline.cs

@@ -4,6 +4,7 @@
 using Microsoft.DotNet.RemoteExecutor;
 using SixLabors.ImageSharp.PixelFormats;
 using SixLabors.ImageSharp.Tests.TestUtilities;
+using SixLabors.ImageSharp.Tests.TestUtilities.ImageComparison;
 using Xunit;
 
 // ReSharper disable InconsistentNaming
@@ -12,17 +13,23 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
     public partial class JpegDecoderTests
     {
         [Theory]
-        [WithFileCollection(nameof(BaselineTestJpegs), PixelTypes.Rgba32)]
-        public void DecodeBaselineJpeg<TPixel>(TestImageProvider<TPixel> provider)
+        [WithFileCollection(nameof(BaselineTestJpegs), PixelTypes.Rgba32, false)]
+        [WithFile(TestImages.Jpeg.Baseline.Calliphora, PixelTypes.Rgba32, true)]
+        public void DecodeBaselineJpeg<TPixel>(TestImageProvider<TPixel> provider, bool enforceNonContiguousBuffers)
             where TPixel : struct, IPixel<TPixel>
         {
-            static void RunTest(string providerDump)
+            static void RunTest(string providerDump, string nonContiguousBuffersStr)
             {
                 TestImageProvider<TPixel> provider =
                     BasicSerializer.Deserialize<TestImageProvider<TPixel>>(providerDump);
 
+                if (!string.IsNullOrEmpty(nonContiguousBuffersStr))
+                {
+                    provider.LimitAllocatorBufferCapacity();
+                }
+
                 using Image<TPixel> image = provider.GetImage(JpegDecoder);
-                image.DebugSave(provider);
+                image.DebugSave(provider, testOutputDetails: nonContiguousBuffersStr);
 
                 provider.Utility.TestName = DecodeBaselineJpegOutputName;
                 image.CompareToReferenceOutput(
@@ -32,7 +39,11 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
             }
 
             string providerDump = BasicSerializer.Serialize(provider);
-            RemoteExecutor.Invoke(RunTest, providerDump).Dispose();
+            RemoteExecutor.Invoke(
+                    RunTest,
+                    providerDump,
+                    enforceNonContiguousBuffers ? "NonContiguous" : string.Empty)
+                .Dispose();
         }
 
         [Theory]

tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Progressive.cs

@@ -14,17 +14,23 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
         public const string DecodeProgressiveJpegOutputName = "DecodeProgressiveJpeg";
 
         [Theory]
-        [WithFileCollection(nameof(ProgressiveTestJpegs), PixelTypes.Rgba32)]
-        public void DecodeProgressiveJpeg<TPixel>(TestImageProvider<TPixel> provider)
+        [WithFileCollection(nameof(ProgressiveTestJpegs), PixelTypes.Rgba32, false)]
+        [WithFile(TestImages.Jpeg.Progressive.Progress, PixelTypes.Rgba32, true)]
+        public void DecodeProgressiveJpeg<TPixel>(TestImageProvider<TPixel> provider, bool enforceNonContiguousBuffers)
             where TPixel : struct, IPixel<TPixel>
         {
-            static void RunTest(string providerDump)
+            static void RunTest(string providerDump, string nonContiguousBuffersStr)
             {
                 TestImageProvider<TPixel> provider =
                     BasicSerializer.Deserialize<TestImageProvider<TPixel>>(providerDump);
 
+                if (!string.IsNullOrEmpty(nonContiguousBuffersStr))
+                {
+                    provider.LimitAllocatorBufferCapacity();
+                }
+
                 using Image<TPixel> image = provider.GetImage(JpegDecoder);
-                image.DebugSave(provider);
+                image.DebugSave(provider, nonContiguousBuffersStr);
 
                 provider.Utility.TestName = DecodeProgressiveJpegOutputName;
                 image.CompareToReferenceOutput(
@@ -33,8 +39,11 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
                     appendPixelTypeToFileName: false);
             }
 
-            string dump = BasicSerializer.Serialize(provider);
-            RemoteExecutor.Invoke(RunTest, dump).Dispose();
+            string providerDump = BasicSerializer.Serialize(provider);
+            RemoteExecutor.Invoke(
+                RunTest,
+                providerDump,
+                enforceNonContiguousBuffers ? "NonContiguous" : string.Empty);
         }
     }
 }

tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.cs

@@ -95,19 +95,14 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
         public void JpegDecoder_IsNotBoundToSinglePixelType<TPixel>(TestImageProvider<TPixel> provider)
             where TPixel : struct, IPixel<TPixel>
         {
-            static void RunTest(string providerDump)
-            {
-                TestImageProvider<TPixel> provider =
-                    BasicSerializer.Deserialize<TestImageProvider<TPixel>>(providerDump);
-                using Image<TPixel> image = provider.GetImage(JpegDecoder);
-                image.DebugSave(provider);
-
-                provider.Utility.TestName = DecodeBaselineJpegOutputName;
-                image.CompareToReferenceOutput(ImageComparer.Tolerant(BaselineTolerance), provider, appendPixelTypeToFileName: false);
-            }
-
-            string dump = BasicSerializer.Serialize(provider);
-            RemoteExecutor.Invoke(RunTest, dump).Dispose();
+            using Image<TPixel> image = provider.GetImage(JpegDecoder);
+            image.DebugSave(provider);
+
+            provider.Utility.TestName = DecodeBaselineJpegOutputName;
+            image.CompareToReferenceOutput(
+                ImageComparer.Tolerant(BaselineTolerance),
+                provider,
+                appendPixelTypeToFileName: false);
         }
 
         // DEBUG ONLY!

tests/ImageSharp.Tests/TestUtilities/ImageProviders/FileProvider.cs

@@ -22,14 +22,18 @@ namespace SixLabors.ImageSharp.Tests
             // are shared between PixelTypes.Color & PixelTypes.Rgba32
             private class Key : IEquatable<Key>
             {
-                private Tuple<PixelTypes, string, Type> commonValues;
+                private readonly Tuple<PixelTypes, string, Type, int> commonValues;
 
-                private Dictionary<string, object> decoderParameters;
+                private readonly Dictionary<string, object> decoderParameters;
 
-                public Key(PixelTypes pixelType, string filePath, IImageDecoder customDecoder)
+                public Key(PixelTypes pixelType, string filePath, int allocatorBufferCapacity, IImageDecoder customDecoder)
                 {
                     Type customType = customDecoder?.GetType();
-                    this.commonValues = new Tuple<PixelTypes, string, Type>(pixelType, filePath, customType);
+                    this.commonValues = new Tuple<PixelTypes, string, Type, int>(
+                        pixelType,
+                        filePath,
+                        customType,
+                        allocatorBufferCapacity);
                     this.decoderParameters = GetDecoderParameters(customDecoder);
                 }
 
@@ -147,12 +151,8 @@ namespace SixLabors.ImageSharp.Tests
             {
                 Guard.NotNull(decoder, nameof(decoder));
 
-                if (!TestEnvironment.Is64BitProcess)
-                {
-                    return this.LoadImage(decoder);
-                }
-
-                var key = new Key(this.PixelType, this.FilePath, decoder);
+                int bufferCapacity = this.Configuration.MemoryAllocator.GetBufferCapacityInBytes();
+                var key = new Key(this.PixelType, this.FilePath, bufferCapacity, decoder);
 
                 Image<TPixel> cachedImage = Cache.GetOrAdd(key, _ => this.LoadImage(decoder));
 

tests/ImageSharp.Tests/TestUtilities/TestImageExtensions.cs

@@ -5,7 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Numerics;
-
+using System.Runtime.CompilerServices;
 using SixLabors.ImageSharp.Advanced;
 using SixLabors.ImageSharp.Advanced.ParallelUtils;
 using SixLabors.ImageSharp.Formats;
@@ -666,6 +666,15 @@ namespace SixLabors.ImageSharp.Tests
             }
         }
 
+        internal static void LimitAllocatorBufferCapacity<TPixel>(
+            this TestImageProvider<TPixel> provider,
+            int bufferCapacityInPixels = 40000) // 200 x 200
+            where TPixel : struct, IPixel<TPixel>
+        {
+            var allocator = (ArrayPoolMemoryAllocator)provider.Configuration.MemoryAllocator;
+            allocator.BufferCapacityInBytes = Unsafe.SizeOf<TPixel>() * bufferCapacityInPixels;
+        }
+
         internal static Image<Rgba32> ToGrayscaleImage(this Buffer2D<float> buffer, float scale)
         {
             var image = new Image<Rgba32>(buffer.Width, buffer.Height);