1. School of Automation, Wuhan University of Technology, Wuhan, China and National Laboratory of Pattern Recognition, CASIA, Beijing, China
2. National Laboratory of Pattern Recognition, CASIA, Beijing, China
3. Beijing Key Laboratory of Multimedia and Intelligent Software Technology, College of Computer, Science and Technology, Beijing University of Technology, Beijing, China
4. School of Automation, Wuhan University of Technology, Wuhan, China