private unsafe byte[] BitmapToRawIndexed(Bitmap source, int maxColors, out byte[][] palette)
{
Bitmap img = source;
byte[] destination = new byte[img.Width * img.Height];
// If this is not a 32-bit ARGB bitmap, convert it to one
if (img.PixelFormat != System.Drawing.Imaging.PixelFormat.Format32bppArgb)
{
Bitmap newImage = new Bitmap(img.Width, img.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
using (System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(newImage))
{
g.DrawImage(img, 0, 0, img.Width, img.Height);
}
img = newImage;
}
// Quantize the image
WuQuantizer quantizer = new WuQuantizer();
m_palette = quantizer.CreatePalette(img, maxColors);
img = (Bitmap)quantizer.QuantizeImage(img, m_palette);
// Copy over the data to the destination. We need to use Stride in this case, as it may not
// always be equal to Width.
BitmapData bitmapData = img.LockBits(new Rectangle(0, 0, img.Width, img.Height), ImageLockMode.ReadOnly, img.PixelFormat);
byte *pointer = (byte *)bitmapData.Scan0;
for (int y = 0; y < bitmapData.Height; y++)
{
for (int x = 0; x < bitmapData.Width; x++)
{
destination[(y * img.Width) + x] = pointer[(y * bitmapData.Stride) + x];
}
}
img.UnlockBits(bitmapData);
// Copy over the palette
palette = new byte[maxColors][];
for (int i = 0; i < maxColors; i++)
{
palette[i] = new byte[4];
palette[i][3] = img.Palette.Entries[i].A;
palette[i][2] = img.Palette.Entries[i].R;
palette[i][1] = img.Palette.Entries[i].G;
palette[i][0] = img.Palette.Entries[i].B;
}
return(destination);
}