diff --git a/Legacy/Legacy.csproj b/Legacy/Legacy.csproj
index 5e34df44..bf409494 100644
--- a/Legacy/Legacy.csproj
+++ b/Legacy/Legacy.csproj
@@ -65,6 +65,8 @@
+
+
diff --git a/Legacy/System21/ArcPAK.cs b/Legacy/System21/ArcPAK.cs
new file mode 100644
index 00000000..be6e5531
--- /dev/null
+++ b/Legacy/System21/ArcPAK.cs
@@ -0,0 +1,73 @@
+//! \file ArcPAK.cs
+//! \date 2017 Dec 09
+//! \brief System21 resource archive.
+//
+// Copyright (C) 2017 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.Collections.Generic;
+using System.ComponentModel.Composition;
+using System.IO;
+
+namespace GameRes.Formats.System21
+{
+ [Export(typeof(ArchiveFormat))]
+ public class PakOpener : ArchiveFormat
+ {
+ public override string Tag { get { return "PAK/SYSTEM21"; } }
+ public override string Description { get { return "System21 engine resource archive"; } }
+ public override uint Signature { get { return 0x978FAD8F; } } // '少女'
+ public override bool IsHierarchic { get { return false; } }
+ public override bool CanWrite { get { return false; } }
+
+ public PakOpener ()
+ {
+ Signatures = new uint[] { 0x978FAD8F, 0x798AF589 }; // '快楽'
+ }
+
+ public override ArcFile TryOpen (ArcView file)
+ {
+ bool new_version = file.View.ReadUInt32 (0) == 0x798AF589u;
+ uint name_size = new_version ? 0x34u : 0x64u;
+ uint data_offset = file.View.ReadUInt32 (4);
+ int count = (int)((data_offset - 12) / (name_size + 4));
+ if (!IsSaneCount (count))
+ return null;
+
+ uint index_offset = 12;
+ var dir = new List (count);
+ for (int i = 0; i < count; ++i)
+ {
+ var name = file.View.ReadString (index_offset, name_size);
+ var entry = FormatCatalog.Instance.Create (name);
+ entry.Offset = data_offset;
+ entry.Size = file.View.ReadUInt32 (index_offset + name_size);
+ if (!entry.CheckPlacement (file.MaxOffset))
+ return null;
+ dir.Add (entry);
+ index_offset += name_size + 4;
+ data_offset += entry.Size;
+ }
+ return new ArcFile (file, this, dir);
+ }
+ }
+}
diff --git a/Legacy/System21/ImageBET.cs b/Legacy/System21/ImageBET.cs
new file mode 100644
index 00000000..dae9015a
--- /dev/null
+++ b/Legacy/System21/ImageBET.cs
@@ -0,0 +1,92 @@
+//! \file ImageBET.cs
+//! \date 2017 Dec 09
+//! \brief System21 compressed image.
+//
+// Copyright (C) 2017 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.ComponentModel.Composition;
+using System.IO;
+using System.Windows.Media;
+using System.Windows.Media.Imaging;
+using GameRes.Compression;
+
+namespace GameRes.Formats.System21
+{
+ [Export(typeof(ImageFormat))]
+ public class BetFormat : ImageFormat
+ {
+ public override string Tag { get { return "BET"; } }
+ public override string Description { get { return "System21 compressed image format"; } }
+ public override uint Signature { get { return 0x44445A53; } } // 'SZDD'
+
+ public override ImageMetaData ReadMetaData (IBinaryStream file)
+ {
+ if (!file.Name.HasExtension (".bet"))
+ return null;
+ using (var lz = OpenLzStream (file.AsStream))
+ using (var input = new BinaryStream (lz, file.Name))
+ {
+ uint w = input.ReadUInt32();
+ uint h = input.ReadUInt32();
+ int bpp = input.ReadUInt16();
+ if ((bpp != 24 && bpp != 8) || 0 == w || w > 0x8000 || 0 == h || h > 0x8000)
+ return null;
+ return new ImageMetaData { Width = w, Height = h, BPP = bpp };
+ }
+ }
+
+ public override ImageData Read (IBinaryStream file, ImageMetaData info)
+ {
+ using (var input = OpenLzStream (file.AsStream))
+ {
+ int stride = (int)info.Width * info.BPP / 8;
+ var pixels = new byte[stride * (int)info.Height];
+ for (int i = 0; i < 10; ++i)
+ input.ReadByte();
+ BitmapPalette palette = null;
+ if (8 == info.BPP)
+ palette = ReadPalette (input);
+ if (input.Read (pixels, 0, pixels.Length) != pixels.Length)
+ throw new InvalidFormatException();
+ for (int i = 0; i < pixels.Length; ++i)
+ pixels[i] ^= 0xFF;
+ PixelFormat format = 8 == info.BPP ? PixelFormats.Indexed8 : PixelFormats.Bgr24;
+ return ImageData.CreateFlipped (info, format, palette, pixels, stride);
+ }
+ }
+
+ Stream OpenLzStream (Stream input)
+ {
+ input.Position = 0xE;
+ var lz = new LzssStream (input, LzssMode.Decompress, true);
+ lz.Config.FrameSize = 0x1000;
+ lz.Config.FrameFill = 0x20;
+ lz.Config.FrameInitPos = 0x1000 - 0x10;
+ return lz;
+ }
+
+ public override void Write (Stream file, ImageData image)
+ {
+ throw new System.NotImplementedException ("BetFormat.Write not implemented");
+ }
+ }
+}