code: def _whiteNoise(self, size):
          
          if self.noise > 0.003921569:  # 1./255.
              w, h = size
  
              pixel = (lambda noise: round(255 * random.uniform(1-noise, 1)))
  
              n_image = Image.new('RGB', size, (0, 0, 0, 0))
              rnd_grid = map(lambda _: tuple([pixel(self.noise)]) * 3,
                             [0] * w * h)
              n_image.putdata(list(rnd_grid))
              return n_image
          else:
              return None
docs: Generate white noise and merge it with given Image object.