public object ReduceColourDepth(object o, BackgroundWorker w, DoWorkEventArgs e)
{
Console.WriteLine("Worker thread: " + this + "," + TargetColours + "," + ColourMap + "," + ColourMap.Count);
// This case we're removing colours one at a time, replacing them with closest colours
if (TargetColours > 0)
{
Console.WriteLine("ReduceColourDepth: initial nColours = " + ColourMap.Count + ", Target: " + TargetColours);
int toRemove = ColourMap.Count - TargetColours;
for (int i = 0; i < toRemove; i++)
{
if (w.CancellationPending)
{
e.Cancel = true;
return(this);
}
IColourInfo least = ColourMap.GetLeastCommonColourInfo(true);
RemoveFromPalette(least);
UpdateColourMapFromImage();
w.ReportProgress(i * 100 / toRemove);
}
Console.WriteLine("ReduceColourDepth: final number of colours = " + ColourMap.Count);
}
else // This case we have no idea how many colours, we just want to fit the colour map.
{
Bitmap orig = mOutput;
Bitmap b = new Bitmap(orig.Width, orig.Height, PixelFormat.Format24bppRgb);
Console.WriteLine("ReduceColourDepth: initial nColours = " + ColourMap.Count);
int i = 0;
for (int x = 0; x < b.Width; x++)
{
for (int y = 0; y < b.Height; y++)
{
if (w.CancellationPending)
{
e.Cancel = true;
return(this);
}
Color c = orig.GetPixel(x, y);
Color newC = ColourMap.GetNearestColour(c);
b.SetPixel(x, y, newC);
w.ReportProgress((i++) * 100 / (b.Width * b.Height));
}
}
mOutput = b;
}
return(this);
}
public void RemoveFromPalette(Color colorToRemove)
{
ColourMap.RemoveColour(colorToRemove);
ReplaceColour(colorToRemove, ColourMap.GetNearestColour(colorToRemove));
}