How can I generate a palette of prominent colors from an image?

Question

I\'m trying to figure out how to sample all of the pixels in an image and generate a palette of colors from it, something like this or this. I have no idea where to even beg

Answer 1

I started here:

System.Drawing.Image img = System.Drawing.Bitmap.FromFile("file");
System.Drawing.Imaging.ColorPalette palette = img.Palette;
foreach (Color color in palette.Entries)
{
  //...
}