def apply(self, clip: Clip) -> Clip:
        """Apply the effect to the clip."""

        def image_filter(im):
            im = 1.0 * im  # float conversion
            corrected = (
                im + self.lum + self.contrast * (im - float(self.contrast_threshold))
            )
            corrected[corrected < 0] = 0
            corrected[corrected > 255] = 255
            return corrected.astype("uint8")

        return clip.image_transform(image_filter)
Apply the effect to the clip.
moviepy/video/fx/LumContrast.py