Add BlurHash support to backend

2 files changed, 49 insertions, 1 deletions

diff --git a/Jellyfin.Drawing.Skia/Jellyfin.Drawing.Skia.csproj b/Jellyfin.Drawing.Skia/Jellyfin.Drawing.Skia.csproj
index a6e1f490a..9f0e3a004 100644
--- a/Jellyfin.Drawing.Skia/Jellyfin.Drawing.Skia.csproj
+++ b/Jellyfin.Drawing.Skia/Jellyfin.Drawing.Skia.csproj
@@ -21,6 +21,8 @@
     <PackageReference Include="SkiaSharp" Version="1.68.1" />
     <PackageReference Include="SkiaSharp.NativeAssets.Linux" Version="1.68.1" />
     <PackageReference Include="Jellyfin.SkiaSharp.NativeAssets.LinuxArm" Version="1.68.1" />
+
+    <PackageReference Include="Blurhash.Core" Version="*" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/Jellyfin.Drawing.Skia/SkiaEncoder.cs b/Jellyfin.Drawing.Skia/SkiaEncoder.cs
index 5c7462ee2..1d7307863 100644
--- a/Jellyfin.Drawing.Skia/SkiaEncoder.cs
+++ b/Jellyfin.Drawing.Skia/SkiaEncoder.cs
@@ -1,7 +1,11 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using Blurhash.Core;
 using MediaBrowser.Common.Configuration;
 using MediaBrowser.Controller.Drawing;
 using MediaBrowser.Controller.Extensions;
@@ -15,7 +19,7 @@ namespace Jellyfin.Drawing.Skia
     /// <summary>
     /// Image encoder that uses <see cref="SkiaSharp"/> to manipulate images.
     /// </summary>
-    public class SkiaEncoder : IImageEncoder
+    public class SkiaEncoder : CoreEncoder, IImageEncoder
     {
         private static readonly HashSet<string> _transparentImageTypes
             = new HashSet<string>(StringComparer.OrdinalIgnoreCase) { ".png", ".gif", ".webp" };
@@ -229,6 +233,48 @@ namespace Jellyfin.Drawing.Skia
             }
         }
 
+        /// <inheritdoc />
+        /// <exception cref="ArgumentNullException">The path is null.</exception>
+        /// <exception cref="FileNotFoundException">The path is not valid.</exception>
+        /// <exception cref="SkiaCodecException">The file at the specified path could not be used to generate a codec.</exception>
+        [SuppressMessage("Microsoft.Performance", "CA1814:PreferJaggedArraysOverMultidimensional")]
+        public string GetImageHash(string path)
+        {
+            if (path == null)
+            {
+                throw new ArgumentNullException(nameof(path));
+            }
+
+            if (!File.Exists(path))
+            {
+                throw new FileNotFoundException("File not found", path);
+            }
+
+            using (var bitmap = GetBitmap(path, false, false, null))
+            {
+                if (bitmap == null)
+                {
+                    throw new ArgumentOutOfRangeException($"Skia unable to read image {path}");
+                }
+
+                var width = bitmap.Width;
+                var height = bitmap.Height;
+                var pixels = new Pixel[width, height];
+                Parallel.ForEach(Enumerable.Range(0, height), y =>
+                {
+                    for (var x = 0; x < width; x++)
+                    {
+                        var color = bitmap.GetPixel(x, y);
+                        pixels[x, y].Red = MathUtils.SRgbToLinear(color.Red);
+                        pixels[x, y].Green = MathUtils.SRgbToLinear(color.Green);
+                        pixels[x, y].Blue = MathUtils.SRgbToLinear(color.Blue);
+                    }
+                });
+
+                return CoreEncode(pixels, 4, 4);
+            }
+        }
+
         private static bool HasDiacritics(string text)
             => !string.Equals(text, text.RemoveDiacritics(), StringComparison.Ordinal);