1. National Engineering Research Center for Geoinformatics, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
2. College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
3. Department of Remote Sensing and Photogrammetry, Finnish Geospatial Research Institute, Espoo, Finland
4. State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, China