4 files changed, 50 insertions, 26 deletions
diff --git a/MediaBrowser.Controller/Drawing/ImageExtensions.cs b/MediaBrowser.Controller/Drawing/ImageExtensions.cs
index 3d3b947a0..92b2ec835 100644
--- a/MediaBrowser.Controller/Drawing/ImageExtensions.cs
+++ b/MediaBrowser.Controller/Drawing/ImageExtensions.cs
@@ -3,7 +3,6 @@ using System.Drawing;
 using System.Drawing.Drawing2D;
 using System.Drawing.Imaging;
 using System.IO;
-using System.Linq;
 
 namespace MediaBrowser.Controller.Drawing
 {
@@ -61,7 +60,15 @@ namespace MediaBrowser.Controller.Drawing
         /// <returns>ImageCodecInfo.</returns>
         private static ImageCodecInfo GetImageCodecInfo(string mimeType)
         {
-            return Encoders.FirstOrDefault(i => i.MimeType.Equals(mimeType, StringComparison.OrdinalIgnoreCase)) ?? Encoders.FirstOrDefault();
+            foreach (var encoder in Encoders)
+            {
+                if (string.Equals(encoder.MimeType, mimeType, StringComparison.OrdinalIgnoreCase))
+                {
+                    return encoder;
+                }
+            }
+
+            return Encoders.Length == 0 ? null : Encoders[0];
         }
 
         /// <summary>
diff --git a/MediaBrowser.Controller/Drawing/ImageHeader.cs b/MediaBrowser.Controller/Drawing/ImageHeader.cs
index 11072ff0c..95a753f00 100644
--- a/MediaBrowser.Controller/Drawing/ImageHeader.cs
+++ b/MediaBrowser.Controller/Drawing/ImageHeader.cs
@@ -18,19 +18,22 @@ namespace MediaBrowser.Controller.Drawing
         /// <summary>
         /// The error message
         /// </summary>
-        const string errorMessage = "Could not recognize image format.";
+        const string ErrorMessage = "Could not recognize image format.";
 
         /// <summary>
         /// The image format decoders
         /// </summary>
-        private static readonly Dictionary<byte[], Func<BinaryReader, Size>> imageFormatDecoders = new Dictionary<byte[], Func<BinaryReader, Size>>
+        private static readonly KeyValuePair<byte[], Func<BinaryReader, Size>>[] ImageFormatDecoders = new Dictionary<byte[], Func<BinaryReader, Size>>
         { 
             { 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 }, 
-        };
+            { new byte[] { 0xff, 0xd8 }, DecodeJfif }
+
+        }.ToArray();
+
+        private static readonly int MaxMagicBytesLength = ImageFormatDecoders.Select(i => i.Key.Length).OrderByDescending(i => i).First();
 
         /// <summary>
         /// Gets the dimensions of an image.
@@ -81,12 +84,13 @@ namespace MediaBrowser.Controller.Drawing
         /// <exception cref="ArgumentException">The image was of an unrecognized format.</exception>
         private static Size GetDimensions(BinaryReader binaryReader)
         {
-            int maxMagicBytesLength = imageFormatDecoders.Keys.OrderByDescending(x => x.Length).First().Length;
-            var magicBytes = new byte[maxMagicBytesLength];
-            for (int i = 0; i < maxMagicBytesLength; i += 1)
+            var magicBytes = new byte[MaxMagicBytesLength];
+
+            for (var i = 0; i < MaxMagicBytesLength; i += 1)
             {
                 magicBytes[i] = binaryReader.ReadByte();
-                foreach (var kvPair in imageFormatDecoders)
+
+                foreach (var kvPair in ImageFormatDecoders)
                 {
                     if (StartsWith(magicBytes, kvPair.Key))
                     {
@@ -95,7 +99,7 @@ namespace MediaBrowser.Controller.Drawing
                 }
             }
 
-            throw new ArgumentException(errorMessage, "binaryReader");
+            throw new ArgumentException(ErrorMessage, "binaryReader");
         }
 
         /// <summary>
@@ -217,7 +221,7 @@ namespace MediaBrowser.Controller.Drawing
                 }
             }
 
-            throw new ArgumentException(errorMessage);
+            throw new ArgumentException(ErrorMessage);
         }
     }
 }
diff --git a/MediaBrowser.Controller/IO/FileData.cs b/MediaBrowser.Controller/IO/FileData.cs
index dc2b49c75..b1fc28e7b 100644
--- a/MediaBrowser.Controller/IO/FileData.cs
+++ b/MediaBrowser.Controller/IO/FileData.cs
@@ -3,8 +3,6 @@ using MediaBrowser.Model.Logging;
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
-using MoreLinq;
 
 namespace MediaBrowser.Controller.IO
 {
@@ -40,9 +38,14 @@ namespace MediaBrowser.Controller.IO
             if (!resolveShortcuts && flattenFolderDepth == 0)
             {
                 // Seeing dupes on some users file system for some reason
-                return entries
-                    .DistinctBy(i => i.FullName, StringComparer.OrdinalIgnoreCase)
-                    .ToDictionary(i => i.FullName, StringComparer.OrdinalIgnoreCase);
+                var dictionary = new Dictionary<string, FileSystemInfo>(StringComparer.OrdinalIgnoreCase);
+
+                foreach (var info in entries)
+                {
+                    dictionary[info.FullName] = info;
+                }
+
+                return dictionary;
             }
 
             var dict = new Dictionary<string, FileSystemInfo>(StringComparer.OrdinalIgnoreCase);
diff --git a/MediaBrowser.Controller/Providers/BaseMetadataProvider.cs b/MediaBrowser.Controller/Providers/BaseMetadataProvider.cs
index b524a11aa..39c999e82 100644
--- a/MediaBrowser.Controller/Providers/BaseMetadataProvider.cs
+++ b/MediaBrowser.Controller/Providers/BaseMetadataProvider.cs
@@ -1,14 +1,14 @@
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
-using MediaBrowser.Common.Extensions;
+using MediaBrowser.Common.Extensions;
 using MediaBrowser.Controller.Configuration;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
 using MediaBrowser.Model.Entities;
 using MediaBrowser.Model.Logging;
 using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -330,6 +330,16 @@ namespace MediaBrowser.Controller.Providers
             return GetFileSystemStamp(item);
         }
 
+        private Dictionary<string, string> _fileStampExtensionsDictionary;
+        private  Dictionary<string, string> FileStampExtensionsDictionary
+        {
+            get
+            {
+                return _fileStampExtensionsDictionary ??
+                       (_fileStampExtensionsDictionary =
+                        FilestampExtensions.ToDictionary(i => i, StringComparer.OrdinalIgnoreCase));
+            }
+        }
         /// <summary>
         /// Gets the file system stamp.
         /// </summary>
@@ -362,20 +372,20 @@ namespace MediaBrowser.Controller.Providers
 
             var sb = new StringBuilder();
 
-            var extensionsList = FilestampExtensions;
-            var extensions = extensionsList.ToDictionary(i => i, StringComparer.OrdinalIgnoreCase);
+            var extensions = FileStampExtensionsDictionary;
+            var numExtensions = extensions.Count;
 
             // Record the name of each file 
             // Need to sort these because accoring to msdn docs, our i/o methods are not guaranteed in any order
             foreach (var file in resolveArgs.FileSystemChildren
-                .Where(i => IncludeInFileStamp(i, extensions, extensionsList.Length))
+                .Where(i => IncludeInFileStamp(i, extensions, numExtensions))
                 .OrderBy(f => f.Name))
             {
                 sb.Append(file.Name);
             }
 
             foreach (var file in resolveArgs.MetadataFiles
-                .Where(i => IncludeInFileStamp(i, extensions, extensionsList.Length))
+                .Where(i => IncludeInFileStamp(i, extensions, numExtensions))
                 .OrderBy(f => f.Name))
             {
                 sb.Append(file.Name);