add image encoder based on ffmpeg

MediaBrowser.Controller/MediaBrowser.Controller.csproj

@@ -157,6 +157,7 @@
     <Compile Include="Localization\ILocalizationManager.cs" />
     <Compile Include="MediaEncoding\ChapterImageRefreshOptions.cs" />
     <Compile Include="MediaEncoding\IEncodingManager.cs" />
+    <Compile Include="MediaEncoding\ImageEncodingOptions.cs" />
     <Compile Include="MediaEncoding\IMediaEncoder.cs" />
     <Compile Include="MediaEncoding\InternalMediaInfoResult.cs" />
     <Compile Include="Net\IHasResultFactory.cs" />

MediaBrowser.Controller/MediaEncoding/IMediaEncoder.cs

@@ -88,6 +88,14 @@ namespace MediaBrowser.Controller.MediaEncoding
         /// <param name="type">The type.</param>
         /// <returns>System.String.</returns>
         string GetInputArgument(string[] inputFiles, InputType type);
+
+        /// <summary>
+        /// Encodes the image.
+        /// </summary>
+        /// <param name="options">The options.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <returns>Task{Stream}.</returns>
+        Task<Stream> EncodeImage(ImageEncodingOptions options, CancellationToken cancellationToken);
     }
 
     /// <summary>

MediaBrowser.Controller/MediaEncoding/ImageEncodingOptions.cs

@@ -0,0 +1,18 @@
+
+namespace MediaBrowser.Controller.MediaEncoding
+{
+    public class ImageEncodingOptions
+    {
+        public string InputPath { get; set; }
+        
+        public int? Width { get; set; }
+
+        public int? Height { get; set; }
+
+        public int? MaxWidth { get; set; }
+
+        public int? MaxHeight { get; set; }
+
+        public string Format { get; set; }
+    }
+}