1. The Chongqing Key Laboratory of Image Cognition, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
2. The Chongqing Engineering Research Center for Spatial Big Data Intelligent Technology, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
3. The School of Computer Science and Cyber Engineering, Guangzhou University, Guangzhou 510006, China