GARbro-mirror/ArcFormats/Valkyria/ImageMG2.cs
2024-10-01 06:49:25 +08:00

264 lines
9.9 KiB
C#

//! \file ImageMG2.cs
//! \date Sat Feb 25 03:08:01 2017
//! \brief Valkyria image format.
//
// 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.ComponentModel.Composition;
using System.IO;
using System.Windows.Media;
using System.Windows.Media.Imaging;
namespace GameRes.Formats.Valkyria
{
internal class Mg2MetaData : ImageMetaData
{
public int ImageLength;
public int AlphaLength;
public IMg2Scheme Scheme;
public ImageFormat Format;
}
internal interface IMg2Scheme
{
Mg2EncryptedStream CreateStream (Stream main, int offset, int length, int key);
ImageData CreateImage (BitmapSource bitmap, ImageMetaData info);
}
[Export(typeof(ImageFormat))]
public class Mg2Format : ImageFormat
{
public override string Tag { get { return "MG2"; } }
public override string Description { get { return "Valkyria image format"; } }
public override uint Signature { get { return 0x4F43494D; } } // 'MICO'
static readonly IMg2Scheme[] KnownSchemes = { new Mg2SchemeV1(), new Mg2SchemeV2(), new Mg2SchemeV3() };
public override ImageMetaData ReadMetaData (IBinaryStream file)
{
var header = file.ReadHeader (0x10);
if (!header.AsciiEqual (4, "CG01") && !header.AsciiEqual (4, "CG02"))
return null;
int length = header.ToInt32 (8);
foreach (var scheme in KnownSchemes)
{
using (var input = scheme.CreateStream (file.AsStream, 0x10, length, length))
using (var img = new BinaryStream (input, file.Name))
{
ImageFormat format;
if (Png.Signature == img.Signature)
format = Png;
else if (0xE0FFD8FF == img.Signature)
format = Jpeg;
else
continue;
var info = format.ReadMetaData (img);
if (null == info)
continue;
return new Mg2MetaData
{
Width = info.Width,
Height = info.Height,
OffsetX = info.OffsetX,
OffsetY = info.OffsetY,
BPP = info.BPP,
ImageLength = length,
AlphaLength = header.ToInt32 (12),
Scheme = scheme,
Format = format,
};
}
}
return null;
}
public override ImageData Read (IBinaryStream file, ImageMetaData info)
{
var meta = (Mg2MetaData)info;
var frame = ReadBitmapSource (file.AsStream, meta);
return meta.Scheme.CreateImage (frame, meta);
}
BitmapSource ReadBitmapSource (Stream file, Mg2MetaData meta)
{
BitmapSource frame;
using (var input = meta.Scheme.CreateStream (file, 0x10, meta.ImageLength, meta.ImageLength))
using (var img = new BinaryStream (input, meta.FileName))
{
var image = meta.Format.Read (img, meta);
frame = image.Bitmap;
if (0 == meta.AlphaLength)
return frame;
}
if (frame.Format.BitsPerPixel != 32)
frame = new FormatConvertedBitmap (frame, PixelFormats.Bgr32, null, 0);
int stride = frame.PixelWidth * 4;
var pixels = new byte[stride * (int)meta.Height];
frame.CopyPixels (pixels, stride, 0);
using (var input = meta.Scheme.CreateStream (file, 0x10+meta.ImageLength, meta.AlphaLength, meta.ImageLength))
{
var decoder = BitmapDecoder.Create (input, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
BitmapSource alpha_frame = decoder.Frames[0];
if (alpha_frame.PixelWidth != frame.PixelWidth || alpha_frame.PixelHeight != frame.PixelHeight)
return BitmapSource.Create ((int)meta.Width, (int)meta.Height,
ImageData.DefaultDpiX, ImageData.DefaultDpiY,
PixelFormats.Bgr32, null, pixels, stride);
alpha_frame = new FormatConvertedBitmap (alpha_frame, PixelFormats.Gray8, null, 0);
var alpha = new byte[alpha_frame.PixelWidth * alpha_frame.PixelHeight];
alpha_frame.CopyPixels (alpha, alpha_frame.PixelWidth, 0);
int src = 0;
for (int dst = 3; dst < pixels.Length; dst += 4)
{
pixels[dst] = alpha[src++];
}
return BitmapSource.Create ((int)meta.Width, (int)meta.Height,
ImageData.DefaultDpiX, ImageData.DefaultDpiY,
PixelFormats.Bgra32, null, pixels, stride);
}
}
public override void Write (Stream file, ImageData image)
{
throw new System.NotImplementedException ("Mg2Format.Write not implemented");
}
}
internal class Mg2EncryptedStream : StreamRegion
{
readonly byte m_version;
readonly int m_threshold;
readonly byte m_key0;
readonly byte m_key1;
protected Mg2EncryptedStream (Stream main, int offset, int length, byte version, int threshold, byte key0, byte key1)
: base (main, offset, length, true)
{
m_version = version;
m_threshold = threshold;
m_key0 = key0;
m_key1 = key1;
}
public static Mg2EncryptedStream CreateV1 (Stream main, int offset, int length)
{
return new Mg2EncryptedStream(main, offset, length, 1, length / 5, 0, 0);
}
public static Mg2EncryptedStream CreateV2 (Stream main, int offset, int length)
{
return new Mg2EncryptedStream( main, offset, length, 2, Math.Min(25, length), (byte)length, 0);
}
public static Mg2EncryptedStream CreateV3 (Stream main, int offset, int length, int key)
{
return new Mg2EncryptedStream(main, offset, length, 3, 0, (byte)(key >> 1), (byte)((key & 1) + (key >> 3)));
}
public override int Read (byte[] buffer, int offset, int count)
{
long pos = Position;
int read = base.Read(buffer, offset, count);
if (m_version == 3)
{
for (int i = 0; i < read; ++i)
{
buffer[offset+i] ^= (byte)((pos >> 4) ^ (pos + m_key0) ^ m_key1);
pos++;
}
}
else
{
for (int i = 0; i < read && pos < m_threshold; ++i)
buffer[offset+i] ^= (byte)(m_key0 + pos++);
}
return read;
}
public override int ReadByte ()
{
long pos = Position;
int b = base.ReadByte();
if (m_version == 3)
{
b ^= (byte)((pos >> 4) ^ (pos + m_key0) ^ m_key1);
}
else
{
if (b != -1 && pos < m_threshold)
b ^= (byte)(m_key0 + pos);
}
return b;
}
}
internal class Mg2SchemeV1 : IMg2Scheme
{
public Mg2EncryptedStream CreateStream (Stream main, int offset, int length, int key)
{
return Mg2EncryptedStream.CreateV1 (main, offset, length);
}
public ImageData CreateImage (BitmapSource frame, ImageMetaData info)
{
frame.Freeze();
return new ImageData (frame, info);
}
}
internal class Mg2SchemeV2 : IMg2Scheme
{
public Mg2EncryptedStream CreateStream (Stream main, int offset, int length, int key)
{
return Mg2EncryptedStream.CreateV2 (main, offset, length);
}
public ImageData CreateImage (BitmapSource frame, ImageMetaData info)
{
frame = new TransformedBitmap (frame, new ScaleTransform { ScaleY = -1 });
frame.Freeze();
return new ImageData (frame, info);
}
}
internal class Mg2SchemeV3 : IMg2Scheme
{
public Mg2EncryptedStream CreateStream (Stream main, int offset, int length, int key)
{
return Mg2EncryptedStream.CreateV3 (main, offset, length, key);
}
public ImageData CreateImage (BitmapSource frame, ImageMetaData info)
{
frame = new TransformedBitmap(frame, new ScaleTransform { ScaleY = -1 });
frame.Freeze();
return new ImageData(frame, info);
}
}
}