中文说明：求取一幅二值图像包含目标区域的最小矩形框，返回矩形框的上下左右边界，然后根据边界坐标在图上画出目标区域。
English Description：
Find the minimum rectangle of a binary image containing the target area, return the upper, lower, left and right boundaries of the rectangle, and then draw the target area on the graph according to the boundary coordinates.