static float alternativeSaturationFromRGB_1(int rgb) {
  int r = (rgb >> 16) & 0xFF;
  int g = (rgb >> 8) & 0xFF;
  int b = rgb & 0xFF;
  double brightness = (r+g+b)/255.0;
  double factor = abs(brightness-0.5)*2;
  ret (float) (saturationFromRGB(rgb)*factor);
}