def _add_surround(image, points):
    """ For better warping results, a set of eight points are imputed across the image borders before triangulation,
    calculated within this function and added to the point list providedself.
    """
    height, width, _ = image.shape
    height_ = height - 1
    width_ = width - 1
    surround_points = [(0, 0), (width // 2, 0), (width_, 0), (0, height // 
        2), (width_, height // 2), (0, height_), (width // 2, height_), (
        width_, height_)]
    appended = points + surround_points
    return appended
