Moved discovery of loggers and weather providers to MEF. Also added support for third-party image processors, also discovered through MEF.

MediaBrowser.Controller/Drawing/BaseImageProcessor.cs

@@ -0,0 +1,33 @@
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Model.Entities;
+using System.Drawing;
+
+namespace MediaBrowser.Controller.Drawing
+{
+    /// <summary>
+    /// Provides a base image processor class that plugins can use to process images as they are being writen to http responses
+    /// Since this is completely modular with MEF, a plugin only needs to have a subclass in their assembly with the following attribute on the class:
+    /// [Export(typeof(BaseImageProcessor))]
+    /// This will require a reference to System.ComponentModel.Composition
+    /// </summary>
+    public abstract class BaseImageProcessor
+    {
+        /// <summary>
+        /// Processes the primary image for a BaseEntity (Person, Studio, User, etc)
+        /// </summary>
+        /// <param name="bitmap">The bitmap holding the original image, after re-sizing</param>
+        /// <param name="graphics">The graphics surface on which the output is drawn</param>
+        /// <param name="entity">The entity that owns the image</param>
+        public abstract void ProcessImage(Bitmap bitmap, Graphics graphics, BaseEntity entity);
+
+        /// <summary>
+        /// Processes an image for a BaseItem
+        /// </summary>
+        /// <param name="bitmap">The bitmap holding the original image, after re-sizing</param>
+        /// <param name="graphics">The graphics surface on which the output is drawn</param>
+        /// <param name="entity">The entity that owns the image</param>
+        /// <param name="imageType">The image type</param>
+        /// <param name="imageIndex">The image index (currently only used with backdrops)</param>
+        public abstract void ProcessImage(Bitmap bitmap, Graphics graphics, BaseItem entity, ImageType imageType, int imageIndex);
+    }
+}