Replace custom image parser with Skia

Emby.Drawing/Common/ImageHeader.cs

@@ -1,242 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using MediaBrowser.Model.Drawing;
-using MediaBrowser.Model.IO;
-using Microsoft.Extensions.Logging;
-
-namespace Emby.Drawing.Common
-{
-    /// <summary>
-    /// Taken from http://stackoverflow.com/questions/111345/getting-image-dimensions-without-reading-the-entire-file/111349
-    /// http://www.codeproject.com/Articles/35978/Reading-Image-Headers-to-Get-Width-and-Height
-    /// Minor improvements including supporting unsigned 16-bit integers when decoding Jfif and added logic
-    /// to load the image using new Bitmap if reading the headers fails
-    /// </summary>
-    public static class ImageHeader
-    {
-        /// <summary>
-        /// The error message
-        /// </summary>
-        const string ErrorMessage = "Could not recognize image format.";
-
-        /// <summary>
-        /// The image format decoders
-        /// </summary>
-        private static readonly KeyValuePair<byte[], Func<BinaryReader, ImageSize>>[] ImageFormatDecoders = new Dictionary<byte[], Func<BinaryReader, ImageSize>>
-        {
-            { new byte[] { 0x42, 0x4D }, DecodeBitmap },
-            { new byte[] { 0x47, 0x49, 0x46, 0x38, 0x37, 0x61 }, DecodeGif },
-            { new byte[] { 0x47, 0x49, 0x46, 0x38, 0x39, 0x61 }, DecodeGif },
-            { new byte[] { 0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A }, DecodePng },
-            { new byte[] { 0xff, 0xd8 }, DecodeJfif }
-
-        }.ToArray();
-
-        private static readonly int MaxMagicBytesLength = ImageFormatDecoders.Select(i => i.Key.Length).OrderByDescending(i => i).First();
-
-        private static string[] SupportedExtensions = new string[] { ".jpg", ".jpeg", ".png", ".gif" };
-
-        /// <summary>
-        /// Gets the dimensions of an image.
-        /// </summary>
-        /// <param name="path">The path of the image to get the dimensions of.</param>
-        /// <param name="logger">The logger.</param>
-        /// <param name="fileSystem">The file system.</param>
-        /// <returns>The dimensions of the specified image.</returns>
-        /// <exception cref="ArgumentException">The image was of an unrecognised format.</exception>
-        public static ImageSize GetDimensions(string path, ILogger logger, IFileSystem fileSystem)
-        {
-            if (string.IsNullOrEmpty(path))
-            {
-                throw new ArgumentNullException(nameof(path));
-            }
-
-            string extension = Path.GetExtension(path).ToLower();
-
-            if (!SupportedExtensions.Contains(extension))
-            {
-                throw new ArgumentException("ImageHeader doesn't support " + extension);
-            }
-
-            using (var fs = fileSystem.OpenRead(path))
-            {
-                using (var binaryReader = new BinaryReader(fs))
-                {
-                    return GetDimensions(binaryReader);
-                }
-            }
-        }
-
-        /// <summary>
-        /// Gets the dimensions of an image.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>Size.</returns>
-        /// <exception cref="ArgumentException">binaryReader</exception>
-        /// <exception cref="ArgumentException">The image was of an unrecognized format.</exception>
-        private static ImageSize GetDimensions(BinaryReader binaryReader)
-        {
-            var magicBytes = new byte[MaxMagicBytesLength];
-
-            for (var i = 0; i < MaxMagicBytesLength; i += 1)
-            {
-                magicBytes[i] = binaryReader.ReadByte();
-
-                foreach (var kvPair in ImageFormatDecoders)
-                {
-                    if (StartsWith(magicBytes, kvPair.Key))
-                    {
-                        return kvPair.Value(binaryReader);
-                    }
-                }
-            }
-
-            throw new ArgumentException(ErrorMessage, nameof(binaryReader));
-        }
-
-        /// <summary>
-        /// Startses the with.
-        /// </summary>
-        /// <param name="thisBytes">The this bytes.</param>
-        /// <param name="thatBytes">The that bytes.</param>
-        /// <returns><c>true</c> if XXXX, <c>false</c> otherwise</returns>
-        private static bool StartsWith(byte[] thisBytes, byte[] thatBytes)
-        {
-            for (int i = 0; i < thatBytes.Length; i += 1)
-            {
-                if (thisBytes[i] != thatBytes[i])
-                {
-                    return false;
-                }
-            }
-
-            return true;
-        }
-
-        /// <summary>
-        /// Reads the little endian int16.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>System.Int16.</returns>
-        private static short ReadLittleEndianInt16(this BinaryReader binaryReader)
-        {
-            var bytes = new byte[sizeof(short)];
-
-            for (int i = 0; i < sizeof(short); i += 1)
-            {
-                bytes[sizeof(short) - 1 - i] = binaryReader.ReadByte();
-            }
-            return BitConverter.ToInt16(bytes, 0);
-        }
-
-        /// <summary>
-        /// Reads the little endian int32.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>System.Int32.</returns>
-        private static int ReadLittleEndianInt32(this BinaryReader binaryReader)
-        {
-            var bytes = new byte[sizeof(int)];
-            for (int i = 0; i < sizeof(int); i += 1)
-            {
-                bytes[sizeof(int) - 1 - i] = binaryReader.ReadByte();
-            }
-            return BitConverter.ToInt32(bytes, 0);
-        }
-
-        /// <summary>
-        /// Decodes the bitmap.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>Size.</returns>
-        private static ImageSize DecodeBitmap(BinaryReader binaryReader)
-        {
-            binaryReader.ReadBytes(16);
-            int width = binaryReader.ReadInt32();
-            int height = binaryReader.ReadInt32();
-            return new ImageSize
-            {
-                Width = width,
-                Height = height
-            };
-        }
-
-        /// <summary>
-        /// Decodes the GIF.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>Size.</returns>
-        private static ImageSize DecodeGif(BinaryReader binaryReader)
-        {
-            int width = binaryReader.ReadInt16();
-            int height = binaryReader.ReadInt16();
-            return new ImageSize
-            {
-                Width = width,
-                Height = height
-            };
-        }
-
-        /// <summary>
-        /// Decodes the PNG.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>Size.</returns>
-        private static ImageSize DecodePng(BinaryReader binaryReader)
-        {
-            binaryReader.ReadBytes(8);
-            int width = ReadLittleEndianInt32(binaryReader);
-            int height = ReadLittleEndianInt32(binaryReader);
-            return new ImageSize
-            {
-                Width = width,
-                Height = height
-            };
-        }
-
-        /// <summary>
-        /// Decodes the jfif.
-        /// </summary>
-        /// <param name="binaryReader">The binary reader.</param>
-        /// <returns>Size.</returns>
-        /// <exception cref="ArgumentException"></exception>
-        private static ImageSize DecodeJfif(BinaryReader binaryReader)
-        {
-            // A JPEG image consists of a sequence of segments,
-            // each beginning with a marker, each of which begins with a 0xFF byte
-            // followed by a byte indicating what kind of marker it is.
-            // Source: https://en.wikipedia.org/wiki/JPEG#Syntax_and_structure
-            while (binaryReader.ReadByte() == 0xff)
-            {
-                byte marker = binaryReader.ReadByte();
-                short chunkLength = binaryReader.ReadLittleEndianInt16();
-                // SOF0: Indicates that this is a baseline DCT-based JPEG,
-                // and specifies the width, height, number of components, and component subsampling
-                // SOF2: Indicates that this is a progressive DCT-based JPEG,
-                // and specifies the width, height, number of components, and component subsampling
-                if (marker == 0xc0 || marker == 0xc2)
-                {
-                    // https://help.accusoft.com/ImageGear/v18.2/Windows/ActiveX/IGAX-10-12.html
-                    binaryReader.ReadByte(); // We don't care about the first byte
-                    int height = binaryReader.ReadLittleEndianInt16();
-                    int width = binaryReader.ReadLittleEndianInt16();
-                    return new ImageSize(width, height);
-                }
-
-                if (chunkLength < 0)
-                {
-                    ushort uchunkLength = (ushort)chunkLength;
-                    binaryReader.ReadBytes(uchunkLength - 2);
-                }
-                else
-                {
-                    binaryReader.ReadBytes(chunkLength - 2);
-                }
-            }
-
-            throw new ArgumentException(ErrorMessage);
-        }
-    }
-}

Emby.Drawing/Emby.Drawing.csproj

@@ -5,6 +5,10 @@
     <ProjectReference Include="..\MediaBrowser.Controller\MediaBrowser.Controller.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="SkiaSharp" Version="1.68.0" />
+  </ItemGroup>
+
   <ItemGroup>
     <Compile Include="..\SharedVersion.cs" />
   </ItemGroup>

Emby.Drawing/ImageProcessor.cs

@@ -1,3 +1,4 @@
+using SkiaSharp;
 using System;
 using System.Collections.Generic;
 using System.Globalization;
@@ -5,7 +6,6 @@ using System.IO;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
-using Emby.Drawing.Common;
 using MediaBrowser.Common.Extensions;
 using MediaBrowser.Controller;
 using MediaBrowser.Controller.Drawing;
@@ -472,7 +472,16 @@ namespace Emby.Drawing
 
             try
             {
-                return ImageHeader.GetDimensions(path, _logger, _fileSystem);
+                using (var s = new SKFileStream(path))
+                    using (var codec = SKCodec.Create(s))
+                    {
+                        var info = codec.Info;
+                        return new ImageSize
+                        {
+                            Height = info.Height,
+                            Width = info.Width
+                        };
+                    }
             }
             catch
             {