Initial commit.

GameRes/ImageJPEG.cs

@@ -0,0 +1,79 @@
+//! \file       ImageJPEG.cs
+//! \date       Thu Jul 17 15:56:27 2014
+//! \brief      JPEG image implementation.
+//
+
+using System;
+using System.IO;
+using System.Text;
+using System.ComponentModel.Composition;
+using System.Windows.Media.Imaging;
+using GameRes.Utility;
+
+namespace GameRes
+{
+    [Export(typeof(ImageFormat))]
+    public class JpegFormat : ImageFormat
+    {
+        public override string Tag { get { return "JPEG"; } }
+        public override string Description { get { return "JPEG image file format"; } }
+        public override uint Signature { get { return 0; } }
+
+        public int Quality { get; set; }
+
+        public JpegFormat ()
+        {
+            Extensions = new string[] { "jpg", "jpeg" };
+            Quality = 90;
+        }
+
+        public override ImageData Read (Stream file, ImageMetaData info)
+        {
+            var decoder = new JpegBitmapDecoder (file,
+                BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
+            var frame = decoder.Frames[0];
+            frame.Freeze();
+            return new ImageData (frame, info);
+        }
+
+        public override void Write (Stream file, ImageData image)
+        {
+            var encoder = new JpegBitmapEncoder();
+            encoder.QualityLevel = Quality;
+            encoder.Frames.Add (BitmapFrame.Create (image.Bitmap));
+            encoder.Save (file);
+        }
+
+        public override ImageMetaData ReadMetaData (Stream stream)
+        {
+            if (0xff != stream.ReadByte() || 0xd8 != stream.ReadByte())
+                return null;
+            using (var file = new ArcView.Reader (stream))
+            {
+                while (-1 != file.PeekChar())
+                {
+                    ushort marker = Binary.BigEndian (file.ReadUInt16());
+                    if ((marker & 0xff00) != 0xff00)
+                        break;
+                    int length = Binary.BigEndian (file.ReadUInt16());
+                    if ((marker & 0x00f0) == 0xc0 && marker != 0xffc4)
+                    {
+                        if (length < 8)
+                            break;
+                        int bits = file.ReadByte();
+                        uint height = Binary.BigEndian (file.ReadUInt16());
+                        uint width  = Binary.BigEndian (file.ReadUInt16());
+                        int components = file.ReadByte();
+                        return new ImageMetaData {
+                            Width = width,
+                            Height = height,
+                            BPP = bits * components,
+                        };
+                    }
+                    file.BaseStream.Seek (length-2, SeekOrigin.Current);
+                }
+                return null;
+            }
+        }
+    }
+}