1 School of Intelligent Systems Engineering, Sun Yat-Sen University, Shenzhen 518107, China.
2 Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A∗STAR), 1 Fusionopolis Way, Singapore 138632, Republic of Singapore.
3 Institute of Space and Earth Information Science, Chinese University of Hong Kong, Hong Kong, China.
4 Key Laboratory of Virtual Geographic Environment (Ministry of Education), Nanjing Normal University, Nanjing 210023, China.
5 Institute of Remote Sensing and Geographical Information System, School of Earth and Space Sciences, Peking University, Beijing 100871, China.
6 State Key Laboratory of Information Engineering in Surveying, Mapping, and Remote Sensing, Wuhan University, Wuhan 430079, China.
7 Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hong Kong, China.