def normalize_min_max(img, a=0.1, b=0.9):
    """
    Normalize the image with Min-Max scaling to a range of [a, b]

    Args:
        img: The image to be normalized

    Returns:
        Normalized image data
    """
    # Assume image data is in grayscale, with the current values in
    # the range [0, 255] (uint8).
    x_min = 0
    x_max = 255

    # x' = a + ((x - x_min) * (b - a)) / (x_max - x_min)
    normalized_img = a + ((img - x_min) * (b - a)) / (x_max - x_min)

    return normalized_img