/// <summary>
/// creates a palette of colors from a bitmap
/// </summary>
/// <param name="bmp">The BMP.</param>
/// <param name="maxcolors">The maxcolors.</param>
/// <returns>Octree.</returns>
/// <exception cref="System.ArgumentException">
/// bmp not valid. use copyimage()
/// or
/// length of colors not valid - value
/// </exception>
public unsafe static Octree FromBitmap(Bitmap bmp, int maxcolors)
{
if (bmp == null || bmp.PixelFormat != PixelFormat.Format32bppArgb)
{
throw new ArgumentException("bmp not valid. use copyimage()");
}
if (maxcolors < 2 || maxcolors > 256)
{
throw new ArgumentException("length of colors not valid", "value");
}
//no exact mapping of colors
Octree ret = new Octree(5, maxcolors);
#region adding bitmap
//lock bitmap
BitmapData bdata = bmp.LockBits(
new Rectangle(0, 0, bmp.Width, bmp.Height),
ImageLockMode.ReadWrite,
PixelFormat.Format32bppArgb);
int count = bmp.Width * bmp.Height;
ColorBgra *pixels = (ColorBgra *)bdata.Scan0;
//loop through pixels
for (int i = 0; i < count; i++)
{
ret.AddColor(pixels[i]);
while (ret._colors > ret._maxcolors)
{
ret.ReduceTree();
}
}
bmp.UnlockBits(bdata);
#endregion
//make palette
ret._table = new ColorBgra[maxcolors];
int index = 0;
ret._root.AddToTable(ret._table, ref index);
//return octree
return(ret);
}
/// <summary>
/// creates an adaptive palette based on the data in the
/// specified bitmap
/// </summary>
/// <param name="bmp">a bitmap containing the colors. use only 32bppArgb images</param>
public void MakePalette(Bitmap bmp)
{
_octree = Octree.FromBitmap(bmp, _maxcolors);
}