Yanbiao Sun 1,2, Fan Zhang 3,*, Yunlong Gao 3 and Xianfeng Huang 3 1 Chinese Academy of Surveying and Mapping, Beijing 100000, China; [email protected] 2 Beijing Key Lab of Spatial Information Integration and Its Applications, Peking University, Beijing 100871, China 3 State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430072, China;...
