Yingbing Liu¹, Wenying Du¹, Nengcheng Chen Dr.^1,2, Changjiang Xiao³ and Xiaolei Wang⁴, (1)Wuhan University, State Key Laboratory of Information Engineering in Surveying, Mapping, and Remote Sensing, Wuhan, China, (2)Collaborative Innovation Center of Geospatial Technology, Wuhan, China, (3)Tongji University, College of Surveying and Geo-informatics, Shanghai, China, (4)Zhengzhou University, Institute of Smart City, Zhengzhou, China