static ImageSurface show332Histogram(BufferedImage img) {
  ret show332Histogram(new RGBImage(img));
}

static ImageSurface show332Histogram(RGBImage img) {
  final new MultiSet<S> histogram = histogram332(img);
  L<S> l = histogram.highestFirst();
  final int max = histogram.get(first(l));
  ret showImage(mergeImagesVertically(allToRGBImage(map(l, func(S col) { imageFromInt(from332(col), max(1, iround(histogram.get(col)*100.0/max)), 30) }))));
}