def hard_black_and_white(img):
    """
    Harsh black and white filter
    :param img: PIL image object
    :return: PIL image object
    """
    # black and white
    gray_img = img.convert('L')
    bw_img = gray_img.point(lambda x: 0 if x < 128 else 255, '1')
    bw_img = bw_img.convert('RGB')
    return bw_img