利用已知控制点，通过空间后方交会求得像片的外方位元素，并利用求得的外方位元素，通过前方交会求出像点的地面摄影测量坐标，并判断外方位元素的精度是否达标。(By using the known control points, the exterior orientation elements of the photo are obtained through the space resection. The ground photogrammetric coordinates of the imag