diff --git a/Legacy/Pochette/ImageGDT.cs b/Legacy/Pochette/ImageGDT.cs
new file mode 100644
index 00000000..f6533920
--- /dev/null
+++ b/Legacy/Pochette/ImageGDT.cs
@@ -0,0 +1,132 @@
+//! \file       ImageGDT.cs
+//! \date       2018 Jan 04
+//! \brief      Pochette bitmap container.
+//
+// Copyright (C) 2018 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 System;
+using System.ComponentModel.Composition;
+using System.IO;
+using System.Windows;
+using System.Windows.Media.Imaging;
+
+namespace GameRes.Formats.Pochette
+{
+    internal class GdtMetaData : ImageMetaData
+    {
+        public uint     BitmapOffset;
+        public string   BaseLine;
+    }
+
+    [Export(typeof(ImageFormat))]
+    public class GdtFormat : ImageFormat
+    {
+        public override string         Tag { get { return "GDT"; } }
+        public override string Description { get { return "Pochette bitmap container"; } }
+        public override uint     Signature { get { return 0; } }
+
+        public override ImageMetaData ReadMetaData (IBinaryStream file)
+        {
+            var header = file.ReadHeader (16);
+            int base_length = header[8];
+            if (base_length != 7 && base_length != 0)
+                return null;
+            var info = Bmp.ReadMetaData (file);
+            if (null == info)
+                return null;
+            string base_name = null;
+            if (base_length != 0)
+            {
+                base_name = header.GetCString (9, base_length);
+                if (string.IsNullOrWhiteSpace (base_name))
+                    base_name = null;
+            }
+            return new GdtMetaData {
+                Width = info.Width,
+                Height = info.Height,
+                OffsetX = header.ToInt16 (0),
+                OffsetY = header.ToInt16 (2),
+                BPP = info.BPP,
+                BitmapOffset = 16,
+                BaseLine = base_name,
+            };
+        }
+
+        public override ImageData Read (IBinaryStream file, ImageMetaData info)
+        {
+            var meta = (GdtMetaData)info;
+            var bitmap = ReadBitmapSource (file, meta);
+            if (null != meta.BaseLine)
+                bitmap = BlendBaseLine (bitmap, meta);
+            bitmap.Freeze();
+            return new ImageData (bitmap, info);
+        }
+
+        BitmapSource ReadBitmapSource (IBinaryStream file, GdtMetaData info)
+        {
+            using (var bmp = new StreamRegion (file.AsStream, info.BitmapOffset, true))
+            {
+                var decoder = new BmpBitmapDecoder (bmp,
+                    BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
+                return decoder.Frames[0];
+            }
+        }
+
+        BitmapSource BlendBaseLine (BitmapSource overlay, GdtMetaData meta)
+        {
+            string base_name = VFS.ChangeFileName (meta.FileName, meta.BaseLine+".gdt");
+            if (!VFS.FileExists (base_name))
+                return overlay;
+            using (var base_file = VFS.OpenBinaryStream (base_name))
+            {
+                var base_info = ReadMetaData (base_file) as GdtMetaData;
+                if (null == base_info)
+                    return overlay;
+                var base_image = ReadBitmapSource (base_file, base_info);
+                var canvas = new WriteableBitmap (base_image);
+                int canvas_bpp = canvas.Format.BitsPerPixel;
+                if (canvas_bpp != overlay.Format.BitsPerPixel)
+                    overlay = new FormatConvertedBitmap (overlay, canvas.Format, null, 0);
+                canvas.Lock();
+                unsafe
+                {
+                    byte* buffer = (byte*)canvas.BackBuffer;
+                    int canvas_stride = canvas.BackBufferStride;
+                    int canvas_size = canvas_stride * canvas.PixelHeight;
+                    int overlay_stride = (overlay.PixelWidth * canvas_bpp + 7) / 8;
+                    int overlay_size = overlay_stride * overlay.PixelHeight;
+                    int pos = meta.OffsetY * canvas_stride + meta.OffsetX * canvas_bpp / 8;
+                    overlay.CopyPixels (Int32Rect.Empty, (IntPtr)(buffer+pos), canvas_size-pos, canvas_stride);
+                }
+                var rect = new Int32Rect (meta.OffsetX, meta.OffsetY, overlay.PixelWidth, overlay.PixelHeight);
+                canvas.AddDirtyRect (rect);
+                canvas.Unlock();
+                return canvas;
+            }
+        }
+
+        public override void Write (Stream file, ImageData image)
+        {
+            throw new System.NotImplementedException ("GdtFormat.Write not implemented");
+        }
+    }
+}