bunch of stuff.

Legacy/James/ImageJMG.cs

@@ -0,0 +1,133 @@
+//! \file       ImageJMG.cs
+//! \date       2022 Jun 11
+//! \brief      JAMES engine encrypted image.
+//
+// Copyright (C) 2022 by morkt
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//
+
+using GameRes.Utility;
+using System.ComponentModel.Composition;
+using System.IO;
+
+// [981105][Berserker] Situation
+// [991109][Berserker] Situation 2
+
+namespace GameRes.Formats.James
+{
+    public enum Obfuscation
+    {
+        None,
+        RotateWords,
+        ReverseBits
+    }
+
+    public class JmgMetaData : ImageMetaData
+    {
+        public Obfuscation      Method;
+        public ImageMetaData    BmpInfo;
+    }
+
+    [Export(typeof(ImageFormat))]
+    public class JmgFormat : ImageFormat
+    {
+        public override string         Tag { get { return "JMG"; } }
+        public override string Description { get { return "JAMES engine obfuscated bitmap"; } }
+        public override uint     Signature { get { return 0; } }
+
+        public override ImageMetaData ReadMetaData (IBinaryStream file)
+        {
+            var header = file.ReadHeader (2);
+            Obfuscation method;
+            if (header[0] == 0xD4 && header[1] == 0x24)
+                method = Obfuscation.RotateWords;
+            else if (header[0] == 0xB2 && header[1] == 0x42)
+                method = Obfuscation.ReverseBits;
+            else
+                return null;
+            using (var input = OpenAsBitmap (file, 0x40, method))
+            {
+                var info = Bmp.ReadMetaData (input);
+                if (null == info)
+                    return null;
+                return new JmgMetaData
+                {
+                    Width   = info.Width,
+                    Height  = info.Height,
+                    BPP     = info.BPP,
+                    Method  = method,
+                    BmpInfo = info,
+                };
+            }
+        }
+
+        IBinaryStream OpenAsBitmap (IBinaryStream input, int length, Obfuscation method)
+        {
+            input.Position = 0;
+            var data = input.ReadBytes (length);
+            Deobfuscate (data, 0, length, method);
+            return new BinMemoryStream (data, input.Name);
+        }
+
+        public override ImageData Read (IBinaryStream file, ImageMetaData info)
+        {
+            var meta = (JmgMetaData)info;
+            using (var bmp = OpenAsBitmap (file, (int)file.Length, meta.Method))
+                return Bmp.Read (bmp, meta.BmpInfo);
+        }
+
+        void Deobfuscate (byte[] data, int pos, int length, Obfuscation method)
+        {
+            switch (method)
+            {
+            case Obfuscation.RotateWords:   RotateWords (data, pos, length); break;
+            case Obfuscation.ReverseBits:   ReverseBits (data, pos, length); break;
+            }
+        }
+
+        void RotateWords (byte[] data, int pos, int length)
+        {
+            for (int i = 0; i < length; i += 2)
+            {
+                ushort w = LittleEndian.ToUInt16 (data, pos+i);
+                w = (ushort)(w >> 12 | w << 4);
+                LittleEndian.Pack (w, data, pos+i);
+            }
+        }
+
+        void ReverseBits (byte[] data, int pos, int length)
+        {
+            for (int i = 0; i < length; i += 2)
+            {
+                int v = LittleEndian.ToUInt16 (data, pos+i);
+                v = (v & 0xAAAA) >> 1 | (v & 0x5555) << 1;
+                v = (v & 0xCCCC) >> 2 | (v & 0x3333) << 2;
+                v = (v & 0xF0F0) >> 4 | (v & 0x0F0F) << 4;
+                v = (v & 0xFF00) >> 8 | (v & 0x00FF) << 8;
+                LittleEndian.Pack ((ushort)v, data, pos+i);
+            }
+        }
+
+        public override void Write (Stream file, ImageData image)
+        {
+            throw new System.NotImplementedException ("JmgFormat.Write not implemented");
+        }
+    }
+}