1. School of Computer Science, China University of Geosciences, Wuhan, China
2. Hubei Key Laboratory of Intelligent Geo-Information Processing, China University of Geosciences, Wuhan, China
3. Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering, China Three Gorges University, Yichang, Hubei, China
4. College of Computer and Information Technology, China Three Gorges University, Yichang, China