Function dilate_rect_u8 

pub fn dilate_rect_u8(
    input: ImageView<'_, u8, 1>,
    element: &StructuringElement,
    iterations: usize,
    border: BorderMode<u8, 1>,
) -> Result<Image<u8, 1>, VisionError>

Dilates a grayscale u8 image with a rectangular element in linear time.