static L<Int> dominant332colors(RGBImage img) {
  int[] array = histogram332_array(img);
  new MultiSet<Int> ms;
  for i over array:
    ms.add(i, array[i]);
  ret ms.highestFirst();
}

static L<Int> dominant332colors(BufferedImage img) {
  ret dominant332colors(RGBImage(img));
}