filterHue :: Double -> Double -> RGB8 -> RGB8
filterHue l r rgb
  | filterHls (l, r) (0, 360) (0, 360) rgb = rgb
  | otherwise = (0, 0, 0)
filterHue :: Double -> Double -> RGB8 -> RGB8
filterHue l r rgb
  | filterHls (l, r) (0, 360) (0, 360) rgb = rgb
  | otherwise = (0, 0, 0)
filterHue l r rgb
  | filterHls (l, r) (0, 360) (0, 360) rgb = rgb
  | otherwise = (0, 0, 0)