diff --git a/ArcFormats/ArcFormats.csproj b/ArcFormats/ArcFormats.csproj
index 63f3500b..6c071820 100644
--- a/ArcFormats/ArcFormats.csproj
+++ b/ArcFormats/ArcFormats.csproj
@@ -123,6 +123,7 @@
+
diff --git a/ArcFormats/Artemis/ImageNekoPNG.cs b/ArcFormats/Artemis/ImageNekoPNG.cs
new file mode 100644
index 00000000..e70af69d
--- /dev/null
+++ b/ArcFormats/Artemis/ImageNekoPNG.cs
@@ -0,0 +1,165 @@
+//! \file ImageNekoPNG.cs
+//! \date Sun Nov 19 15:40:46 2023
+//! \brief NekoNyan PNG image format.
+//
+// Copyright (C) 2016 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;
+using System.ComponentModel.Composition;
+using System.IO;
+using System.Reflection;
+using System.Runtime.InteropServices;
+using System.Windows.Media.Imaging;
+using System.Windows.Media;
+using System.Windows;
+
+namespace GameRes.Formats.Artemis
+{
+ internal class NekoPNGMetaData : ImageMetaData
+ {
+ public int[] Offset;
+ public int[] Length;
+ }
+
+ [Export(typeof(ImageFormat))]
+ public class ImageNekoPNG : ImageFormat
+ {
+ public override string Tag { get { return "PNG"; } }
+ public override string Description { get { return "NekoNyan PNG image format"; } }
+ public override uint Signature { get { return 0x00000040; } }
+
+ public override ImageData Read (IBinaryStream file, ImageMetaData info)
+ {
+ var metadata = (NekoPNGMetaData)info;
+ var bitmap = new WriteableBitmap ((int)info.Width, (int)info.Height, ImageData.DefaultDpiX, ImageData.DefaultDpiY, PixelFormats.Bgra32, null);
+ bitmap.Lock ();
+ try
+ {
+ var output = bitmap.BackBuffer;
+ int stride = bitmap.BackBufferStride;
+ for (var i = 0; i < 8; i++)
+ {
+ file.Position = metadata.Offset[i];
+ var data = file.ReadBytes (metadata.Length[i]);
+ for (var j = 0; j < 16; j++)
+ data[j] -= (byte)(0x77 * j);
+ var slice_width = 0;
+ var slice_height = 0;
+ if (1 != WebPGetInfo (data, (UIntPtr)data.Length, ref slice_width, ref slice_height))
+ throw new InvalidFormatException("WebP image decoder failed.");
+ var slice_size = stride * slice_height;
+ if (IntPtr.Zero == WebPDecodeBGRAInto (data, (UIntPtr)data.Length, output, (UIntPtr)slice_size, stride))
+ throw new InvalidFormatException("WebP image decoder failed.");
+ output += slice_size;
+ }
+ bitmap.AddDirtyRect (new Int32Rect(0, 0, (int)info.Width, (int)info.Height));
+ }
+ finally
+ {
+ bitmap.Unlock();
+ }
+ bitmap.Freeze();
+ return new ImageData (bitmap, info);
+ }
+
+ public override ImageMetaData ReadMetaData (IBinaryStream file)
+ {
+ if (file.Signature != 0x40)
+ return null;
+ if (file.Length <= 0x40)
+ return null;
+ var offset = new int[8];
+ var length = new int[8];
+ for (var i = 0; i < 8; i++)
+ offset[i] = file.ReadInt32();
+ for (var i = 0; i < 8; i++)
+ length[i] = file.ReadInt32();
+ LibWebPLoader.Load();
+ var image_width = 0;
+ var image_height = 0;
+ for (var i = 0; i < 8; i++)
+ {
+ if (offset[i] < 64)
+ return null;
+ if (length[i] < 32)
+ return null;
+ if (offset[i] + length[i] > file.Length)
+ return null;
+ file.Position = offset[i];
+ var webp_header = file.ReadBytes (32);
+ for (var j = 0; j < 16; j++)
+ webp_header[j] -= (byte)(0x77 * j);
+ var slice_width = 0;
+ var slice_height = 0;
+ if (1 != WebPGetInfo (webp_header, (UIntPtr)webp_header.Length, ref slice_width, ref slice_height))
+ throw new InvalidFormatException ("WebP image decoder failed.");
+ image_width = Math.Max (image_width, slice_width);
+ image_height += slice_height;
+ }
+ return new NekoPNGMetaData
+ {
+ Width = (uint)image_width,
+ Height = (uint)image_height,
+ BPP = 32,
+ Offset = offset,
+ Length = length,
+ };
+ }
+
+ public override void Write (Stream file, ImageData bitmap)
+ {
+ throw new NotImplementedException("ImageNekoPNG.Write not implemented");
+ }
+
+ [DllImport("libwebp.dll", EntryPoint = "WebPGetInfo", CallingConvention = CallingConvention.Cdecl)]
+ public static extern int WebPGetInfo ([MarshalAs(UnmanagedType.LPArray)] byte[] data, UIntPtr data_size, ref int width, ref int height);
+
+ [DllImport("libwebp.dll", EntryPoint = "WebPDecodeBGRAInto", CallingConvention = CallingConvention.Cdecl)]
+ public static extern IntPtr WebPDecodeBGRAInto ([MarshalAs(UnmanagedType.LPArray)] byte[] data, UIntPtr data_size, IntPtr output_buffer, UIntPtr output_buffer_size, int output_stride);
+ }
+
+ internal static class LibWebPLoader
+ {
+ [DllImport("kernel32.dll", SetLastError = true, CallingConvention = CallingConvention.StdCall)]
+ static extern IntPtr LoadLibraryEx (string lpFileName, IntPtr hReservedNull, uint dwFlags);
+
+ static bool loaded = false;
+
+ const uint LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR = 0x00000100;
+ const uint LOAD_LIBRARY_SEARCH_SYSTEM32 = 0x00000800;
+
+ public static void Load ()
+ {
+ if (loaded)
+ return;
+ var folder = Path.GetDirectoryName (Assembly.GetExecutingAssembly().Location);
+ folder = Path.Combine (folder, (IntPtr.Size == 4) ? "x86" : "x64");
+ var fullPath = Path.Combine (folder, "libwebp.dll");
+ fullPath = Path.GetFullPath (fullPath);
+ var handle = LoadLibraryEx (fullPath, IntPtr.Zero, LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR | LOAD_LIBRARY_SEARCH_SYSTEM32);
+ if (IntPtr.Zero == handle)
+ throw new Win32Exception (Marshal.GetLastWin32Error());
+ loaded = true;
+ }
+ }
+}