JpegEncoderCore has "only" 862 lines now

src/ImageSharp/Formats/Jpg/Components/Block8x8F.cs

@@ -103,6 +103,22 @@ namespace ImageSharp.Formats
             Marshal.Copy((IntPtr)blockPtr, dest.Data, dest.Offset, ScalarCount);
         }
 
+        /// <summary>
+        /// Convert salars to byte-s and copy to dest
+        /// </summary>
+        /// <param name="blockPtr">Pointer to block</param>
+        /// <param name="dest">Destination</param>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static unsafe void CopyTo(Block8x8F* blockPtr, MutableSpan<byte> dest)
+        {
+            float* fPtr = (float*)blockPtr;
+            for (int i = 0; i < ScalarCount; i++)
+            {
+                dest[i] = (byte) *fPtr;
+                fPtr++;
+            }
+        }
+
         /// <summary>
         /// Load raw 32bit floating point data from source
         /// </summary>
@@ -128,7 +144,7 @@ namespace ImageSharp.Formats
                 Marshal.Copy((IntPtr)ptr, dest.Data, dest.Offset, ScalarCount);
             }
         }
-
+        
         /// <summary>
         /// Copy raw 32bit floating point data to dest
         /// </summary>

src/ImageSharp/Formats/Jpg/Components/HuffIndex.cs

@@ -0,0 +1,32 @@
+namespace ImageSharp.Formats.Jpg.Components
+{
+    /// <summary>
+    /// Enumerates the Huffman tables
+    /// </summary>
+    internal enum HuffIndex
+    {
+        /// <summary>
+        /// The DC luminance huffman table index
+        /// </summary>
+        LuminanceDC = 0,
+
+        // ReSharper disable UnusedMember.Local
+
+        /// <summary>
+        /// The AC luminance huffman table index
+        /// </summary>
+        LuminanceAC = 1,
+
+        /// <summary>
+        /// The DC chrominance huffman table index
+        /// </summary>
+        ChrominanceDC = 2,
+
+        /// <summary>
+        /// The AC chrominance huffman table index
+        /// </summary>
+        ChrominanceAC = 3,
+
+        // ReSharper restore UnusedMember.Local
+    }
+}

src/ImageSharp/Formats/Jpg/Components/HuffmanLut.cs

@@ -0,0 +1,68 @@
+namespace ImageSharp.Formats.Jpg.Components
+{
+    /// <summary>
+    /// A compiled look-up table representation of a huffmanSpec.
+    /// Each value maps to a uint32 of which the 8 most significant bits hold the
+    /// codeword size in bits and the 24 least significant bits hold the codeword.
+    /// The maximum codeword size is 16 bits.
+    /// </summary>
+    internal struct HuffmanLut
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="HuffmanLut"/> class.
+        /// </summary>
+        /// <param name="spec">The encoding specifications.</param>
+        public HuffmanLut(HuffmanSpec spec)
+        {
+            int maxValue = 0;
+
+            foreach (byte v in spec.Values)
+            {
+                if (v > maxValue)
+                {
+                    maxValue = v;
+                }
+            }
+
+            this.Values = new uint[maxValue + 1];
+
+            int code = 0;
+            int k = 0;
+
+            for (int i = 0; i < spec.Count.Length; i++)
+            {
+                int bits = (i + 1) << 24;
+                for (int j = 0; j < spec.Count[i]; j++)
+                {
+                    this.Values[spec.Values[k]] = (uint)(bits | code);
+                    code++;
+                    k++;
+                }
+
+                code <<= 1;
+            }
+        }
+
+        /// <summary>
+        /// Initialize static members
+        /// </summary>
+        static HuffmanLut()
+        {
+            // Initialize the Huffman tables
+            for (int i = 0; i < HuffmanSpec.TheHuffmanSpecs.Length; i++)
+            {
+                HuffmanLut.TheHuffmanLut[i] = new HuffmanLut(HuffmanSpec.TheHuffmanSpecs[i]);
+            }
+        }
+
+        /// <summary>
+        /// Gets the collection of huffman values.
+        /// </summary>
+        public uint[] Values { get; }
+
+        /// <summary>
+        /// The compiled representations of theHuffmanSpec.
+        /// </summary>
+        public static readonly HuffmanLut[] TheHuffmanLut = new HuffmanLut[4];
+    }
+}

src/ImageSharp/Formats/Jpg/Components/HuffmanSpec.cs

@@ -0,0 +1,112 @@
+namespace ImageSharp.Formats.Jpg.Components
+{
+    /// <summary>
+    /// The Huffman encoding specifications.
+    /// </summary>
+    internal struct HuffmanSpec
+    {
+        /// <summary>
+        /// Gets count[i] - The number of codes of length i bits.
+        /// </summary>
+        public readonly byte[] Count;
+
+        /// <summary>
+        /// Gets value[i] - The decoded value of the codeword at the given index.
+        /// </summary>
+        public readonly byte[] Values;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="HuffmanSpec"/> struct.
+        /// </summary>
+        /// <param name="count">The number of codes.</param>
+        /// <param name="values">The decoded values.</param>
+        public HuffmanSpec(byte[] count, byte[] values)
+        {
+            this.Count = count;
+            this.Values = values;
+        }
+
+#pragma warning disable SA1118 // ParameterMustNotSpanMultipleLines
+        /// <summary>
+        /// The Huffman encoding specifications.
+        /// This encoder uses the same Huffman encoding for all images.
+        /// </summary>
+        public static readonly HuffmanSpec[] TheHuffmanSpecs =
+            {
+                // Luminance DC.
+                new HuffmanSpec(
+                    new byte[]
+                        {
+                            0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0
+                        },
+                    new byte[]
+                        {
+                            0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+                        }),
+                new HuffmanSpec(
+                    new byte[]
+                        {
+                            0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 125
+                        },
+                    new byte[]
+                        {
+                            0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 0x21,
+                            0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 0x22, 0x71,
+                            0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1,
+                            0xc1, 0x15, 0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72,
+                            0x82, 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25,
+                            0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37,
+                            0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
+                            0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
+                            0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a,
+                            0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x83,
+                            0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93,
+                            0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3,
+                            0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3,
+                            0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
+                            0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3,
+                            0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
+                            0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf1,
+                            0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa
+                        }),
+                new HuffmanSpec(
+                    new byte[]
+                        {
+                            0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0
+                        },
+                    new byte[]
+                        {
+                            0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+                        }),
+
+                // Chrominance AC.
+                new HuffmanSpec(
+                    new byte[]
+                        {
+                            0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 119
+                        },
+                    new byte[]
+                        {
+                            0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31,
+                            0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22,
+                            0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, 0xc1,
+                            0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62, 0x72, 0xd1,
+                            0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25, 0xf1, 0x17, 0x18,
+                            0x19, 0x1a, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36,
+                            0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47,
+                            0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
+                            0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
+                            0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
+                            0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a,
+                            0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a,
+                            0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa,
+                            0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba,
+                            0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca,
+                            0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
+                            0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
+                            0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa
+                        })
+            };
+#pragma warning restore SA1118 // ParameterMustNotSpanMultipleLines
+    }
+}

src/ImageSharp/Formats/Jpg/Components/QuantIndex.cs

@@ -0,0 +1,18 @@
+namespace ImageSharp.Formats.Jpg.Components
+{
+    /// <summary>
+    /// Enumerates the quantization tables
+    /// </summary>
+    internal enum QuantIndex
+    {
+        /// <summary>
+        /// The luminance quantization table index
+        /// </summary>
+        Luminance = 0,
+
+        /// <summary>
+        /// The chrominance quantization table index
+        /// </summary>
+        Chrominance = 1,
+    }
+}

src/ImageSharp/Formats/Jpg/JpegEncoderCore.cs

@@ -2,14 +2,16 @@
 // Copyright (c) James Jackson-South and contributors.
 // Licensed under the Apache License, Version 2.0.
 // </copyright>
-
 namespace ImageSharp.Formats
 {
     using System;
+    using System.Buffers;
     using System.IO;
     using System.Numerics;
     using System.Runtime.CompilerServices;
 
+    using ImageSharp.Formats.Jpg.Components;
+
     /// <summary>
     /// Image encoder for writing an image to a stream as a jpeg.
     /// </summary>
@@ -20,95 +22,6 @@ namespace ImageSharp.Formats
         /// </summary>
         private const int QuantizationTableCount = 2;
 
-#pragma warning disable SA1118 // ParameterMustNotSpanMultipleLines
-
-        /// <summary>
-        /// The Huffman encoding specifications.
-        /// This encoder uses the same Huffman encoding for all images.
-        /// </summary>
-        private static readonly HuffmanSpec[] TheHuffmanSpecs =
-        {
-            // Luminance DC.
-            new HuffmanSpec(
-                new byte[]
-                {
-                    0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0
-                },
-                new byte[]
-                {
-                    0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
-                }),
-            new HuffmanSpec(
-                new byte[]
-                {
-                    0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 125
-                },
-                new byte[]
-                {
-                    0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 0x21,
-                    0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 0x22, 0x71,
-                    0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1,
-                    0xc1, 0x15, 0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72,
-                    0x82, 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25,
-                    0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37,
-                    0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
-                    0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
-                    0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a,
-                    0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x83,
-                    0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93,
-                    0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3,
-                    0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3,
-                    0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
-                    0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3,
-                    0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
-                    0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf1,
-                    0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa
-                }),
-            new HuffmanSpec(
-                new byte[]
-                {
-                    0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0
-                },
-                new byte[]
-                {
-                    0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
-                }),
-
-            // Chrominance AC.
-            new HuffmanSpec(
-                new byte[]
-                {
-                    0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 119
-                },
-                new byte[]
-                {
-                    0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31,
-                    0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22,
-                    0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, 0xc1,
-                    0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62, 0x72, 0xd1,
-                    0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25, 0xf1, 0x17, 0x18,
-                    0x19, 0x1a, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36,
-                    0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47,
-                    0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
-                    0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
-                    0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
-                    0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a,
-                    0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a,
-                    0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa,
-                    0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba,
-                    0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca,
-                    0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
-                    0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
-                    0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa
-                })
-        };
-#pragma warning restore SA1118 // ParameterMustNotSpanMultipleLines
-
-        /// <summary>
-        /// The compiled representations of theHuffmanSpec.
-        /// </summary>
-        private static readonly HuffmanLut[] TheHuffmanLut = new HuffmanLut[4];
-
         /// <summary>
         /// Counts the number of bits needed to hold an integer.
         /// </summary>
@@ -129,32 +42,6 @@ namespace ImageSharp.Formats
                 8, 8, 8,
             };
 
-        /// <summary>
-        /// The unscaled quantization tables in zig-zag order. Each
-        /// encoder copies and scales the tables according to its quality parameter.
-        /// The values are derived from section K.1 after converting from natural to
-        /// zig-zag order.
-        /// </summary>
-        private static readonly byte[,] UnscaledQuant =
-            {
-                    {
-                        // Luminance.
-                        16, 11, 12, 14, 12, 10, 16, 14, 13, 14, 18, 17, 16, 19, 24,
-                        40, 26, 24, 22, 22, 24, 49, 35, 37, 29, 40, 58, 51, 61, 60,
-                        57, 51, 56, 55, 64, 72, 92, 78, 64, 68, 87, 69, 55, 56, 80,
-                        109, 81, 87, 95, 98, 103, 104, 103, 62, 77, 113, 121, 112,
-                        100, 120, 92, 101, 103, 99,
-                    },
-                    {
-                        // Chrominance.
-                        17, 18, 18, 24, 21, 24, 47, 26, 26, 47, 99, 66, 56, 66,
-                        99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
-                        99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
-                        99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
-                        99, 99, 99, 99, 99, 99, 99, 99,
-                    }
-            };
-
         /// <summary>
         /// The SOS (Start Of Scan) marker "\xff\xda" followed by 12 bytes:
         /// - the marker length "\x00\x0c",
@@ -168,7 +55,9 @@ namespace ImageSharp.Formats
         /// </summary>
         private static readonly byte[] SosHeaderYCbCr =
             {
-                JpegConstants.Markers.XFF, JpegConstants.Markers.SOS, // Marker
+                JpegConstants.Markers.XFF, JpegConstants.Markers.SOS,
+
+                // Marker
                 0x00, 0x0c,
 
                 // Length (high byte, low byte), must be 6 + 2 * (number of components in scan)
@@ -181,7 +70,35 @@ namespace ImageSharp.Formats
                 0x11, // DC/AC Huffman table
                 0x00, // Ss - Start of spectral selection.
                 0x3f, // Se - End of spectral selection.
-                0x00 // Ah + Ah (Successive approximation bit position high + low)
+                0x00
+
+                // Ah + Ah (Successive approximation bit position high + low)
+            };
+
+        /// <summary>
+        /// The unscaled quantization tables in zig-zag order. Each
+        /// encoder copies and scales the tables according to its quality parameter.
+        /// The values are derived from section K.1 after converting from natural to
+        /// zig-zag order.
+        /// </summary>
+        private static readonly byte[,] UnscaledQuant =
+            {
+                    {
+                        // Luminance.
+                        16, 11, 12, 14, 12, 10, 16, 14, 13, 14, 18, 17, 16, 19, 24,
+                        40, 26, 24, 22, 22, 24, 49, 35, 37, 29, 40, 58, 51, 61, 60,
+                        57, 51, 56, 55, 64, 72, 92, 78, 64, 68, 87, 69, 55, 56, 80,
+                        109, 81, 87, 95, 98, 103, 104, 103, 62, 77, 113, 121, 112,
+                        100, 120, 92, 101, 103, 99,
+                    },
+                    {
+                        // Chrominance.
+                        17, 18, 18, 24, 21, 24, 47, 26, 26, 47, 99, 66, 56, 66,
+                        99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+                        99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+                        99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
+                        99, 99, 99, 99, 99, 99, 99, 99,
+                    }
             };
 
         /// <summary>
@@ -199,16 +116,6 @@ namespace ImageSharp.Formats
         /// </summary>
         private readonly byte[] huffmanBuffer = new byte[179];
 
-        /// <summary>
-        /// The scaled luminance table, in zig-zag order.
-        /// </summary>
-        private Block8x8F luminanceQuantTable;
-
-        /// <summary>
-        /// The scaled chrominance table, in zig-zag order.
-        /// </summary>
-        private Block8x8F chrominanceQuantTable;
-
         /// <summary>
         /// The accumulated bits to write to the stream.
         /// </summary>
@@ -220,72 +127,24 @@ namespace ImageSharp.Formats
         private uint bitCount;
 
         /// <summary>
-        /// The output stream. All attempted writes after the first error become no-ops.
-        /// </summary>
-        private Stream outputStream;
-
-        /// <summary>
-        /// The subsampling method to use.
+        /// The scaled chrominance table, in zig-zag order.
         /// </summary>
-        private JpegSubsample subsample;
+        private Block8x8F chrominanceQuantTable;
 
         /// <summary>
-        /// Initializes static members of the <see cref="JpegEncoderCore"/> class.
+        /// The scaled luminance table, in zig-zag order.
         /// </summary>
-        static JpegEncoderCore()
-        {
-            // Initialize the Huffman tables
-            for (int i = 0; i < TheHuffmanSpecs.Length; i++)
-            {
-                TheHuffmanLut[i] = new HuffmanLut(TheHuffmanSpecs[i]);
-            }
-        }
+        private Block8x8F luminanceQuantTable;
 
         /// <summary>
-        /// Enumerates the Huffman tables
+        /// The output stream. All attempted writes after the first error become no-ops.
         /// </summary>
-        private enum HuffIndex
-        {
-            /// <summary>
-            /// The DC luminance huffman table index
-            /// </summary>
-            LuminanceDC = 0,
-
-            // ReSharper disable UnusedMember.Local
-
-            /// <summary>
-            /// The AC luminance huffman table index
-            /// </summary>
-            LuminanceAC = 1,
-
-            /// <summary>
-            /// The DC chrominance huffman table index
-            /// </summary>
-            ChrominanceDC = 2,
-
-            /// <summary>
-            /// The AC chrominance huffman table index
-            /// </summary>
-            ChrominanceAC = 3,
-
-            // ReSharper restore UnusedMember.Local
-        }
+        private Stream outputStream;
 
         /// <summary>
-        /// Enumerates the quantization tables
+        /// The subsampling method to use.
         /// </summary>
-        private enum QuantIndex
-        {
-            /// <summary>
-            /// The luminance quantization table index
-            /// </summary>
-            Luminance = 0,
-
-            /// <summary>
-            /// The chrominance quantization table index
-            /// </summary>
-            Chrominance = 1,
-        }
+        private JpegSubsample subsample;
 
         /// <summary>
         /// Encode writes the image to the jpeg baseline format with the given options.
@@ -403,8 +262,7 @@ namespace ImageSharp.Formats
             Block8x8F* yBlock,
             Block8x8F* cbBlock,
             Block8x8F* crBlock,
-            PixelArea<TColor> rgbBytes)
-            where TColor : struct, IPackedPixel, IEquatable<TColor>
+            PixelArea<TColor> rgbBytes) where TColor : struct, IPackedPixel, IEquatable<TColor>
         {
             float* yBlockRaw = (float*)yBlock;
             float* cbBlockRaw = (float*)cbBlock;
@@ -438,6 +296,18 @@ namespace ImageSharp.Formats
             }
         }
 
+#pragma warning disable SA1204
+        private static void WriteDataToDqt(byte[] dqt, ref int offset, QuantIndex i, ref Block8x8F q)
+        {
+            dqt[offset++] = (byte)i;
+            for (int j = 0; j < Block8x8F.ScalarCount; j++)
+            {
+                dqt[offset++] = (byte)q[j];
+            }
+        }
+
+#pragma warning restore SA1204
+
         /// <summary>
         /// Emits the least significant count of bits of bits to the bit-stream.
         /// The precondition is bits <example>&lt; 1&lt;&lt;nBits &amp;&amp; nBits &lt;= 16</example>.
@@ -486,7 +356,7 @@ namespace ImageSharp.Formats
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private void EmitHuff(HuffIndex index, int value)
         {
-            uint x = TheHuffmanLut[(int)index].Values[value];
+            uint x = HuffmanLut.TheHuffmanLut[(int)index].Values[value];
             this.Emit(x & ((1 << 24) - 1), x >> 24);
         }
 
@@ -524,6 +394,107 @@ namespace ImageSharp.Formats
             }
         }
 
+        /// <summary>
+        /// Encodes the image with no subsampling.
+        /// </summary>
+        /// <typeparam name="TColor">The pixel format.</typeparam>
+        /// <param name="pixels">The pixel accessor providing access to the image pixels.</param>
+        private void Encode444<TColor>(PixelAccessor<TColor> pixels)
+            where TColor : struct, IPackedPixel, IEquatable<TColor>
+        {
+            // TODO: Need a JpegEncoderScanImpl<TColor> struct to encapsulate all this mess:
+            Block8x8F b = default(Block8x8F);
+            Block8x8F cb = default(Block8x8F);
+            Block8x8F cr = default(Block8x8F);
+
+            Block8x8F temp1 = default(Block8x8F);
+            Block8x8F temp2 = default(Block8x8F);
+
+            Block8x8F onStackLuminanceQuantTable = this.luminanceQuantTable;
+            Block8x8F onStackChrominanceQuantTable = this.chrominanceQuantTable;
+
+            UnzigData unzig = UnzigData.Create();
+
+            // ReSharper disable once InconsistentNaming
+            float prevDCY = 0, prevDCCb = 0, prevDCCr = 0;
+
+            using (PixelArea<TColor> rgbBytes = new PixelArea<TColor>(8, 8, ComponentOrder.XYZ, true))
+            {
+                for (int y = 0; y < pixels.Height; y += 8)
+                {
+                    for (int x = 0; x < pixels.Width; x += 8)
+                    {
+                        ToYCbCr(pixels, x, y, &b, &cb, &cr, rgbBytes);
+
+                        prevDCY = this.WriteBlock(
+                            QuantIndex.Luminance,
+                            prevDCY,
+                            &b,
+                            &temp1,
+                            &temp2,
+                            &onStackLuminanceQuantTable,
+                            unzig.Data);
+                        prevDCCb = this.WriteBlock(
+                            QuantIndex.Chrominance,
+                            prevDCCb,
+                            &cb,
+                            &temp1,
+                            &temp2,
+                            &onStackChrominanceQuantTable,
+                            unzig.Data);
+                        prevDCCr = this.WriteBlock(
+                            QuantIndex.Chrominance,
+                            prevDCCr,
+                            &cr,
+                            &temp1,
+                            &temp2,
+                            &onStackChrominanceQuantTable,
+                            unzig.Data);
+                    }
+                }
+            }
+        }
+
+        /// <summary>
+        /// Writes the application header containing the JFIF identifier plus extra data.
+        /// </summary>
+        /// <param name="horizontalResolution">The resolution of the image in the x- direction.</param>
+        /// <param name="verticalResolution">The resolution of the image in the y- direction.</param>
+        private void WriteApplicationHeader(short horizontalResolution, short verticalResolution)
+        {
+            // Write the start of image marker. Markers are always prefixed with with 0xff.
+            this.buffer[0] = JpegConstants.Markers.XFF;
+            this.buffer[1] = JpegConstants.Markers.SOI;
+
+            // Write the JFIF headers
+            this.buffer[2] = JpegConstants.Markers.XFF;
+            this.buffer[3] = JpegConstants.Markers.APP0; // Application Marker
+            this.buffer[4] = 0x00;
+            this.buffer[5] = 0x10;
+            this.buffer[6] = 0x4a; // J
+            this.buffer[7] = 0x46; // F
+            this.buffer[8] = 0x49; // I
+            this.buffer[9] = 0x46; // F
+            this.buffer[10] = 0x00; // = "JFIF",'\0'
+            this.buffer[11] = 0x01; // versionhi
+            this.buffer[12] = 0x01; // versionlo
+            this.buffer[13] = 0x01; // xyunits as dpi
+
+            // No thumbnail
+            this.buffer[14] = 0x00; // Thumbnail width
+            this.buffer[15] = 0x00; // Thumbnail height
+
+            this.outputStream.Write(this.buffer, 0, 16);
+
+            // Resolution. Big Endian
+            this.buffer[0] = (byte)(horizontalResolution >> 8);
+            this.buffer[1] = (byte)horizontalResolution;
+            this.buffer[2] = (byte)(verticalResolution >> 8);
+            this.buffer[3] = (byte)verticalResolution;
+
+            this.outputStream.Write(this.buffer, 0, 4);
+        }
+
         /// <summary>
         /// Writes a block of pixel data using the given quantization table,
         /// returning the post-quantized DC value of the DCT-transformed block.
@@ -591,54 +562,74 @@ namespace ImageSharp.Formats
         }
 
         /// <summary>
-        /// Writes the application header containing the JFIF identifier plus extra data.
+        /// Writes the Define Huffman Table marker and tables.
         /// </summary>
-        /// <param name="horizontalResolution">The resolution of the image in the x- direction.</param>
-        /// <param name="verticalResolution">The resolution of the image in the y- direction.</param>
-        private void WriteApplicationHeader(short horizontalResolution, short verticalResolution)
+        /// <param name="componentCount">The number of components to write.</param>
+        private void WriteDefineHuffmanTables(int componentCount)
         {
-            // Write the start of image marker. Markers are always prefixed with with 0xff.
-            this.buffer[0] = JpegConstants.Markers.XFF;
-            this.buffer[1] = JpegConstants.Markers.SOI;
+            // Table identifiers.
+            byte[] headers = { 0x00, 0x10, 0x01, 0x11 };
+            int markerlen = 2;
+            HuffmanSpec[] specs = HuffmanSpec.TheHuffmanSpecs;
 
-            // Write the JFIF headers
-            this.buffer[2] = JpegConstants.Markers.XFF;
-            this.buffer[3] = JpegConstants.Markers.APP0; // Application Marker
-            this.buffer[4] = 0x00;
-            this.buffer[5] = 0x10;
-            this.buffer[6] = 0x4a; // J
-            this.buffer[7] = 0x46; // F
-            this.buffer[8] = 0x49; // I
-            this.buffer[9] = 0x46; // F
-            this.buffer[10] = 0x00; // = "JFIF",'\0'
-            this.buffer[11] = 0x01; // versionhi
-            this.buffer[12] = 0x01; // versionlo
-            this.buffer[13] = 0x01; // xyunits as dpi
+            if (componentCount == 1)
+            {
+                // Drop the Chrominance tables.
+                specs = new[] { HuffmanSpec.TheHuffmanSpecs[0], HuffmanSpec.TheHuffmanSpecs[1] };
+            }
 
-            // No thumbnail
-            this.buffer[14] = 0x00; // Thumbnail width
-            this.buffer[15] = 0x00; // Thumbnail height
+            foreach (HuffmanSpec s in specs)
+            {
+                markerlen += 1 + 16 + s.Values.Length;
+            }
 
-            this.outputStream.Write(this.buffer, 0, 16);
+            this.WriteMarkerHeader(JpegConstants.Markers.DHT, markerlen);
+            for (int i = 0; i < specs.Length; i++)
+            {
+                HuffmanSpec spec = specs[i];
+                int len = 0;
 
-            // Resolution. Big Endian
-            this.buffer[0] = (byte)(horizontalResolution >> 8);
-            this.buffer[1] = (byte)horizontalResolution;
-            this.buffer[2] = (byte)(verticalResolution >> 8);
-            this.buffer[3] = (byte)verticalResolution;
+                fixed (byte* huffman = this.huffmanBuffer)
+                fixed (byte* count = spec.Count)
+                fixed (byte* values = spec.Values)
+                {
+                    huffman[len++] = headers[i];
 
-            this.outputStream.Write(this.buffer, 0, 4);
+                    for (int c = 0; c < spec.Count.Length; c++)
+                    {
+                        huffman[len++] = count[c];
+                    }
+
+                    for (int v = 0; v < spec.Values.Length; v++)
+                    {
+                        huffman[len++] = values[v];
+                    }
+                }
+
+                this.outputStream.Write(this.huffmanBuffer, 0, len);
+            }
         }
 
         /// <summary>
-        /// Writes the metadata profiles to the image.
+        /// Writes the Define Quantization Marker and tables.
         /// </summary>
-        /// <param name="image">The image.</param>
-        /// <typeparam name="TColor">The pixel format.</typeparam>
-        private void WriteProfiles<TColor>(Image<TColor> image)
-            where TColor : struct, IPackedPixel, IEquatable<TColor>
+        private void WriteDefineQuantizationTables()
         {
-            this.WriteProfile(image.ExifProfile);
+            // Marker + quantization table lengths
+            int markerlen = 2 + (QuantizationTableCount * (1 + Block8x8F.ScalarCount));
+            this.WriteMarkerHeader(JpegConstants.Markers.DQT, markerlen);
+
+            // Loop through and collect the tables as one array.
+            // This allows us to reduce the number of writes to the stream.
+            int dqtCount = (QuantizationTableCount * Block8x8F.ScalarCount) + QuantizationTableCount;
+            byte[] dqt = ArrayPool<byte>.Shared.Rent(dqtCount);
+            int offset = 0;
+
+            WriteDataToDqt(dqt, ref offset, QuantIndex.Luminance, ref this.luminanceQuantTable);
+            WriteDataToDqt(dqt, ref offset, QuantIndex.Chrominance, ref this.chrominanceQuantTable);
+
+            this.outputStream.Write(dqt, 0, dqtCount);
+            ArrayPool<byte>.Shared.Return(dqt);
         }
 
         /// <summary>
@@ -674,35 +665,14 @@ namespace ImageSharp.Formats
         }
 
         /// <summary>
-        /// Writes the Define Quantization Marker and tables.
+        /// Writes the metadata profiles to the image.
         /// </summary>
-        private void WriteDefineQuantizationTables()
-        {
-            // Marker + quantization table lengths
-            int markerlen = 2 + (QuantizationTableCount * (1 + Block8x8F.ScalarCount));
-            this.WriteMarkerHeader(JpegConstants.Markers.DQT, markerlen);
-
-            // Loop through and collect the tables as one array.
-            // This allows us to reduce the number of writes to the stream.
-            byte[] dqt = new byte[(QuantizationTableCount * Block8x8F.ScalarCount) + QuantizationTableCount];
-            int offset = 0;
-
-            WriteDataToDqt(dqt, ref offset, QuantIndex.Luminance, ref this.luminanceQuantTable);
-            WriteDataToDqt(dqt, ref offset, QuantIndex.Chrominance, ref this.chrominanceQuantTable);
-
-            this.outputStream.Write(dqt, 0, dqt.Length);
-        }
-
-#pragma warning disable SA1204
-        private static void WriteDataToDqt(byte[] dqt, ref int offset, QuantIndex i, ref Block8x8F q)
+        /// <param name="image">The image.</param>
+        /// <typeparam name="TColor">The pixel format.</typeparam>
+        private void WriteProfiles<TColor>(Image<TColor> image) where TColor : struct, IPackedPixel, IEquatable<TColor>
         {
-            dqt[offset++] = (byte)i;
-            for (int j = 0; j < Block8x8F.ScalarCount; j++)
-            {
-                dqt[offset++] = (byte)q[j];
-            }
+            this.WriteProfile(image.ExifProfile);
         }
-#pragma warning restore SA1204
 
         /// <summary>
         /// Writes the Start Of Frame (Baseline) marker
@@ -760,55 +730,6 @@ namespace ImageSharp.Formats
             this.outputStream.Write(this.buffer, 0, (3 * (componentCount - 1)) + 9);
         }
 
-        /// <summary>
-        /// Writes the Define Huffman Table marker and tables.
-        /// </summary>
-        /// <param name="componentCount">The number of components to write.</param>
-        private void WriteDefineHuffmanTables(int componentCount)
-        {
-            // Table identifiers.
-            byte[] headers = { 0x00, 0x10, 0x01, 0x11 };
-            int markerlen = 2;
-            HuffmanSpec[] specs = TheHuffmanSpecs;
-
-            if (componentCount == 1)
-            {
-                // Drop the Chrominance tables.
-                specs = new[] { TheHuffmanSpecs[0], TheHuffmanSpecs[1] };
-            }
-
-            foreach (HuffmanSpec s in specs)
-            {
-                markerlen += 1 + 16 + s.Values.Length;
-            }
-
-            this.WriteMarkerHeader(JpegConstants.Markers.DHT, markerlen);
-            for (int i = 0; i < specs.Length; i++)
-            {
-                HuffmanSpec spec = specs[i];
-                int len = 0;
-
-                fixed (byte* huffman = this.huffmanBuffer)
-                fixed (byte* count = spec.Count)
-                fixed (byte* values = spec.Values)
-                {
-                    huffman[len++] = headers[i];
-
-                    for (int c = 0; c < spec.Count.Length; c++)
-                    {
-                        huffman[len++] = count[c];
-                    }
-
-                    for (int v = 0; v < spec.Values.Length; v++)
-                    {
-                        huffman[len++] = values[v];
-                    }
-                }
-
-                this.outputStream.Write(this.huffmanBuffer, 0, len);
-            }
-        }
-
         /// <summary>
         /// Writes the StartOfScan marker.
         /// </summary>
@@ -819,6 +740,7 @@ namespace ImageSharp.Formats
         private void WriteStartOfScan<TColor>(PixelAccessor<TColor> pixels)
             where TColor : struct, IPackedPixel, IEquatable<TColor>
         {
+            // TODO: This method should be the entry point for a JpegEncoderScanImpl<TColor> struct
             // TODO: We should allow grayscale writing.
             this.outputStream.Write(SosHeaderYCbCr, 0, SosHeaderYCbCr.Length);
 
@@ -836,67 +758,6 @@ namespace ImageSharp.Formats
             this.Emit(0x7f, 7);
         }
 
-        /// <summary>
-        /// Encodes the image with no subsampling.
-        /// </summary>
-        /// <typeparam name="TColor">The pixel format.</typeparam>
-        /// <param name="pixels">The pixel accessor providing access to the image pixels.</param>
-        private void Encode444<TColor>(PixelAccessor<TColor> pixels)
-            where TColor : struct, IPackedPixel, IEquatable<TColor>
-        {
-            // TODO: Need a JpegEncoderCoreCore<TColor> class or struct to hold all this mess:
-            Block8x8F b = default(Block8x8F);
-            Block8x8F cb = default(Block8x8F);
-            Block8x8F cr = default(Block8x8F);
-
-            Block8x8F temp1 = default(Block8x8F);
-            Block8x8F temp2 = default(Block8x8F);
-
-            Block8x8F onStackLuminanceQuantTable = this.luminanceQuantTable;
-            Block8x8F onStackChrominanceQuantTable = this.chrominanceQuantTable;
-
-            UnzigData unzig = UnzigData.Create();
-
-            // ReSharper disable once InconsistentNaming
-            float prevDCY = 0, prevDCCb = 0, prevDCCr = 0;
-
-            using (PixelArea<TColor> rgbBytes = new PixelArea<TColor>(8, 8, ComponentOrder.XYZ, true))
-            {
-                for (int y = 0; y < pixels.Height; y += 8)
-                {
-                    for (int x = 0; x < pixels.Width; x += 8)
-                    {
-                        ToYCbCr(pixels, x, y, &b, &cb, &cr, rgbBytes);
-
-                        prevDCY = this.WriteBlock(
-                            QuantIndex.Luminance,
-                            prevDCY,
-                            &b,
-                            &temp1,
-                            &temp2,
-                            &onStackLuminanceQuantTable,
-                            unzig.Data);
-                        prevDCCb = this.WriteBlock(
-                            QuantIndex.Chrominance,
-                            prevDCCb,
-                            &cb,
-                            &temp1,
-                            &temp2,
-                            &onStackChrominanceQuantTable,
-                            unzig.Data);
-                        prevDCCr = this.WriteBlock(
-                            QuantIndex.Chrominance,
-                            prevDCCr,
-                            &cr,
-                            &temp1,
-                            &temp2,
-                            &onStackChrominanceQuantTable,
-                            unzig.Data);
-                    }
-                }
-            }
-        }
-
 #pragma warning disable SA1201 // MethodShouldNotFollowAStruct
 
         /// <summary>
@@ -916,7 +777,7 @@ namespace ImageSharp.Formats
         private void Encode420<TColor>(PixelAccessor<TColor> pixels)
             where TColor : struct, IPackedPixel, IEquatable<TColor>
         {
-            // TODO: Need a JpegEncoderCoreCore<TColor> class or struct to hold all this mess:
+            // TODO: Need a JpegEncoderScanImpl<TColor> struct to encapsulate all this mess:
             Block8x8F b = default(Block8x8F);
 
             BlockQuad cb = default(BlockQuad);
@@ -997,81 +858,5 @@ namespace ImageSharp.Formats
             this.buffer[3] = (byte)(length & 0xff);
             this.outputStream.Write(this.buffer, 0, 4);
         }
-
-        /// <summary>
-        /// The Huffman encoding specifications.
-        /// </summary>
-        private struct HuffmanSpec
-        {
-            /// <summary>
-            /// Gets count[i] - The number of codes of length i bits.
-            /// </summary>
-            public readonly byte[] Count;
-
-            /// <summary>
-            /// Gets value[i] - The decoded value of the codeword at the given index.
-            /// </summary>
-            public readonly byte[] Values;
-
-            /// <summary>
-            /// Initializes a new instance of the <see cref="HuffmanSpec"/> struct.
-            /// </summary>
-            /// <param name="count">The number of codes.</param>
-            /// <param name="values">The decoded values.</param>
-            public HuffmanSpec(byte[] count, byte[] values)
-            {
-                this.Count = count;
-                this.Values = values;
-            }
-        }
-
-        /// <summary>
-        /// A compiled look-up table representation of a huffmanSpec.
-        /// Each value maps to a uint32 of which the 8 most significant bits hold the
-        /// codeword size in bits and the 24 least significant bits hold the codeword.
-        /// The maximum codeword size is 16 bits.
-        /// </summary>
-        private class HuffmanLut
-        {
-            /// <summary>
-            /// Initializes a new instance of the <see cref="HuffmanLut"/> class.
-            /// </summary>
-            /// <param name="spec">The encoding specifications.</param>
-            public HuffmanLut(HuffmanSpec spec)
-            {
-                int maxValue = 0;
-
-                foreach (byte v in spec.Values)
-                {
-                    if (v > maxValue)
-                    {
-                        maxValue = v;
-                    }
-                }
-
-                this.Values = new uint[maxValue + 1];
-
-                int code = 0;
-                int k = 0;
-
-                for (int i = 0; i < spec.Count.Length; i++)
-                {
-                    int bits = (i + 1) << 24;
-                    for (int j = 0; j < spec.Count[i]; j++)
-                    {
-                        this.Values[spec.Values[k]] = (uint)(bits | code);
-                        code++;
-                        k++;
-                    }
-
-                    code <<= 1;
-                }
-            }
-
-            /// <summary>
-            /// Gets the collection of huffman values.
-            /// </summary>
-            public uint[] Values { get; }
-        }
     }
-}
+}

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

@@ -72,7 +72,7 @@ namespace ImageSharp.Tests
             //PixelTypes.Color | PixelTypes.StandardImageClass | PixelTypes.Argb;
 
         [Theory(
-            //Skip = "Benchmark, enable manually!"
+            Skip = "Benchmark, enable manually!"
             )]
         [WithFileCollection(nameof(BenchmarkFiles), BenchmarkPixels, JpegSubsample.Ratio420, 75)]
         [WithFileCollection(nameof(BenchmarkFiles), BenchmarkPixels, JpegSubsample.Ratio444, 75)]

tests/ImageSharp.Tests46/Formats/Jpg/ReferenceImplementationsTests.cs

@@ -1,145 +0,0 @@
-// ReSharper disable InconsistentNaming
-namespace ImageSharp.Tests
-{
-    using System.Numerics;
-    using ImageSharp.Formats;
-    
-    using Xunit;
-    using Xunit.Abstractions;
-
-    public class ReferenceImplementationsTests : UtilityTestClassBase
-    {
-        public ReferenceImplementationsTests(ITestOutputHelper output)
-            : base(output)
-        {
-        }
-
-
-        [Theory]
-        [InlineData(42)]
-        [InlineData(1)]
-        [InlineData(2)]
-        public void Idct_FloatingPointReferenceImplementation_IsEquivalentToIntegerImplementation(int seed)
-        {
-            MutableSpan<int> intData = Create8x8RandomIntData(-200, 200, seed);
-            MutableSpan<float> floatSrc = intData.ConvertToFloat32MutableSpan();
-
-            ReferenceImplementations.IntegerReferenceDCT.TransformIDCTInplace(intData);
-            
-            MutableSpan<float> dest = new MutableSpan<float>(64);
-            MutableSpan<float> temp = new MutableSpan<float>(64);
-
-            ReferenceImplementations.iDCT2D_llm(floatSrc, dest, temp);
-
-            for (int i = 0; i < 64; i++)
-            {
-                float expected = intData[i];
-                float actual = dest[i];
-
-                Assert.Equal(expected, actual, new ApproximateFloatComparer(1f));
-            }
-        }
-
-        [Theory]
-        [InlineData(42, 0)]
-        [InlineData(1, 0)]
-        [InlineData(2, 0)]
-        public void IntegerDCT_ForwardThenInverse(int seed, int startAt)
-        {
-            MutableSpan<int> original = Create8x8RandomIntData(-200, 200, seed);
-
-            var block = original.AddScalarToAllValues(128);
-
-            ReferenceImplementations.IntegerReferenceDCT.TransformFDCTInplace(block);
-            
-            for (int i = 0; i < 64; i++)
-            {
-                block[i] /= 8;
-            }
-
-            ReferenceImplementations.IntegerReferenceDCT.TransformIDCTInplace(block);
-            
-            for (int i = startAt; i < 64; i++)
-            {
-                float expected = original[i];
-                float actual = (float)block[i];
-
-                Assert.Equal(expected, actual, new ApproximateFloatComparer(3f));
-            }
-
-        }
-
-        [Theory]
-        [InlineData(42, 0)]
-        [InlineData(1, 0)]
-        [InlineData(2, 0)]
-        public void FloatingPointDCT_ReferenceImplementation_ForwardThenInverse(int seed, int startAt)
-        {
-            var data = Create8x8RandomIntData(-200, 200, seed);
-            MutableSpan<float> src = new MutableSpan<int>(data).ConvertToFloat32MutableSpan();
-            MutableSpan<float> dest = new MutableSpan<float>(64);
-            MutableSpan<float> temp = new MutableSpan<float>(64);
-
-            ReferenceImplementations.fDCT2D_llm(src, dest, temp, true);
-            ReferenceImplementations.iDCT2D_llm(dest, src, temp);
-
-            for (int i = startAt; i < 64; i++)
-            {
-                float expected = data[i];
-                float actual = (float)src[i];
-                
-                Assert.Equal(expected, actual, new ApproximateFloatComparer(2f));
-            }
-        }
-
-        [Fact]
-        public void HowMuchIsTheFish()
-        {
-            Output.WriteLine(Vector<int>.Count.ToString());
-        }
-
-        [Theory]
-        [InlineData(42)]
-        [InlineData(1)]
-        [InlineData(2)]
-        public void Fdct_FloatingPointReferenceImplementation_IsEquivalentToIntegerImplementation(int seed)
-        {
-            MutableSpan<int> intData = Create8x8RandomIntData(-200, 200, seed);
-            MutableSpan<float> floatSrc = intData.ConvertToFloat32MutableSpan();
-            
-            ReferenceImplementations.IntegerReferenceDCT.TransformFDCTInplace(intData);
-            
-            MutableSpan<float> dest = new MutableSpan<float>(64);
-            MutableSpan<float> temp = new MutableSpan<float>(64);
-
-            ReferenceImplementations.fDCT2D_llm(floatSrc, dest, temp, offsetSourceByNeg128: true);
-
-            for (int i = 0; i < 64; i++)
-            {
-                float expected = intData[i];
-                float actual = dest[i];
-
-                Assert.Equal(expected, actual, new ApproximateFloatComparer(1f));
-            }
-        }
-
-        [Theory]
-        [InlineData(42)]
-        [InlineData(1)]
-        [InlineData(2)]
-        public void Fdct_SimdReferenceImplementation_IsEquivalentToFloatingPointReferenceImplementation(int seed)
-        {
-            Block classic = new Block() { Data = Create8x8RandomIntData(-200, 200, seed) };
-            MutableSpan<float> src = new MutableSpan<int>(classic.Data).ConvertToFloat32MutableSpan();
-
-            MutableSpan<float> dest1 = new MutableSpan<float>(64);
-            MutableSpan<float> dest2 = new MutableSpan<float>(64);
-            MutableSpan<float> temp = new MutableSpan<float>(64);
-
-            ReferenceImplementations.fDCT2D_llm(src, dest1, temp, downscaleBy8: true, offsetSourceByNeg128: false);
-            ReferenceImplementations.fDCT8x8_llm_sse(src, dest2, temp);
-            
-            Assert.Equal(dest1.Data, dest2.Data, new ApproximateFloatComparer(1f));
-        }
-    }
-}

tests/ImageSharp.Tests46/ImageSharp.Tests46.csproj

@@ -82,6 +82,9 @@
     <Compile Include="..\ImageSharp.Tests\Formats\Jpg\ReferenceImplementations.cs">
       <Link>Formats\Jpg\ReferenceImplementations.cs</Link>
     </Compile>
+    <Compile Include="..\ImageSharp.Tests\Formats\Jpg\ReferenceImplementationsTests.cs">
+      <Link>Formats\Jpg\ReferenceImplementationsTests.cs</Link>
+    </Compile>
     <Compile Include="..\ImageSharp.Tests\Formats\Jpg\UtilityTestClassBase.cs">
       <Link>Formats\Jpg\UtilityTestClassBase.cs</Link>
     </Compile>
@@ -157,7 +160,6 @@
     <Compile Include="..\ImageSharp.Tests\TestUtilities\TestUtilityExtensions.cs">
       <Link>TestUtilities\TestUtilityExtensions.cs</Link>
     </Compile>
-    <Compile Include="Formats\Jpg\ReferenceImplementationsTests.cs" />
     <Compile Include="HelloTest.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="TestFile.cs" />