Research Center of Perception and Computing, School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China. luogongning@hit.edu.cn.|Research Center of Perception and Computing, School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China. suidong10@gmail.com.|Research Center of Perception and Computing, School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China. wangkq@hit.edu.cn.|Department of Computer Science and Engineering, Incheon National University, Incheon, Korea. jschae@inu.ac.kr.