static DecodedBitmap DecodeBitmap(BitmapInfoHeader header, IList <Rgb> palette, byte[] data)
{
if (header.BitmapCompression != BitmapCompression.None)
{
return(null);
}
DecodedBitmap bitmap = new DecodedBitmap
{
BitsPerPixel = header.BitsPerPlane,
Height = header.Height,
Width = header.Width,
Pixels = new int[header.Width * header.Height]
};
int[] argbPalette = new int[palette.Count];
for (int c = 0; c < palette.Count; c++)
{
argbPalette[c] = (palette[c].Red << 16) + (palette[c].Green << 8) + palette[c].Blue;
}
long pos = 0;
for (int y = 0; y < bitmap.Height; y++)
{
int x = 0;
while (x < bitmap.Width)
{
for (int k = (int)(8 - bitmap.BitsPerPixel); k >= 0; k -= (int)bitmap.BitsPerPixel)
{
bitmap.Pixels[y * bitmap.Width + x] =
argbPalette[(data[pos] >> k) & ((1 << (int)bitmap.BitsPerPixel) - 1)];
x++;
if (x == bitmap.Width)
{
break;
}
}
pos++;
}
pos += pos % 2;
}
return(bitmap);
}
/// <summary>
/// This will decode an icon
/// </summary>
/// <param name="data">Data</param>
/// <returns>A <see cref="DecodedBitmap" /> with the icon, null if the icon could not be decoded</returns>
public static DecodedBitmap DecodeIcon(byte[] data)
{
long pos = 0;
byte[] buffer = new byte[Marshal.SizeOf(typeof(BitmapInfoHeader))];
Array.Copy(data, pos, buffer, 0, buffer.Length);
BitmapInfoHeader bitmapFileHeader =
BigEndianMarshal.ByteArrayToStructureLittleEndian <BitmapInfoHeader>(buffer);
// Stop at unknown header
if (bitmapFileHeader.HeaderSize != 40)
{
return(null);
}
// Multiplanes not supported
if (bitmapFileHeader.Planes != 1)
{
return(null);
}
// TODO: Non paletted?
pos += bitmapFileHeader.HeaderSize;
Rgb[] palette = new Rgb[1 << bitmapFileHeader.BitsPerPlane];
buffer = new byte[Marshal.SizeOf(typeof(Rgb))];
for (int i = 0; i < palette.Length; i++)
{
Array.Copy(data, pos, buffer, 0, buffer.Length);
pos += buffer.Length;
palette[i] = BigEndianMarshal.ByteArrayToStructureLittleEndian <Rgb>(buffer);
}
// First let's do the icon itself
bitmapFileHeader.Height /= 2;
long dataLength = 0;
for (int y = 0; y < bitmapFileHeader.Height; y++)
{
int x = 0;
while (x < bitmapFileHeader.Width)
{
for (int k = 8 - bitmapFileHeader.BitsPerPlane; k >= 0; k -= (int)bitmapFileHeader.BitsPerPlane)
{
x++;
}
dataLength++;
}
dataLength += dataLength % 2;
}
buffer = new byte[dataLength];
Array.Copy(data, pos, buffer, 0, buffer.Length);
DecodedBitmap icon = DecodeBitmap(bitmapFileHeader, palette, buffer);
// Then the mask
pos += dataLength;
bitmapFileHeader.BitsPerPlane = 1;
dataLength = 0;
for (int y = 0; y < bitmapFileHeader.Height; y++)
{
int x = 0;
while (x < bitmapFileHeader.Width)
{
for (int k = 8 - bitmapFileHeader.BitsPerPlane; k >= 0; k -= (int)bitmapFileHeader.BitsPerPlane)
{
x++;
}
dataLength++;
}
dataLength += dataLength % 2;
}
buffer = new byte[dataLength];
Array.Copy(data, pos, buffer, 0, buffer.Length);
DecodedBitmap mask = DecodeBitmap(bitmapFileHeader, palette, buffer);
// Mask palette
int[] argbPalette = new int[palette.Length];
for (int c = 0; c < palette.Length; c++)
{
argbPalette[c] = (palette[c].Red << 16) + (palette[c].Green << 8) + palette[c].Blue;
}
DecodedBitmap bitmap = new DecodedBitmap
{
BitsPerPixel = icon.BitsPerPixel,
Height = icon.Height,
Width = icon.Width,
Pixels = new int[icon.Pixels.Length]
};
for (int px = 0; px < bitmap.Pixels.Length; px++)
{
bitmap.Pixels[px] = icon.Pixels[px] + (mask.Pixels[px] == argbPalette[0] ? VISIBLE : 0);
}
// Need to reverse first all pixels then by line
int[] pixels = bitmap.Pixels.Reverse().ToArray();
for (int y = 0; y < bitmap.Height; y++)
{
for (int x = 0; x < bitmap.Width; x++)
{
bitmap.Pixels[y * bitmap.Width + (bitmap.Width - x - 1)] = pixels[y * bitmap.Width + x];
}
}
return(bitmap);
}
