将物体的边界以每次3°左右的增量在90°范围内旋转。每旋转一次记录一次其坐标系方向上的外接矩形边界点的最大和最小x、y值。旋转到某一个角度后，外接矩形的面积达到最小。取面积最小的外接矩形的参数为主轴意义下的长度和宽度。

-The boundaries of each object in increments of about 3 to rotate within the 90 range. Each rotation time recording the maximum and minimum x, y values ​ ​ of a circumscribed rectangle boundary point coordinates its direction. Rotate to a certain angle, the external area of ​ ​ a rectangle to a minimum. Take the smallest rectangle circumscribed parameters for the length and width of the spindle sense.