1. School of Information Science and Technology, ShanghaiTech University & Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Shanghai, China
2. Department of Computer Vision Technology (VIS), Baidu Inc., Beijing, China
3. Department of Electrical Engineering (ESAT), KU Leuven, Leuven, Belgium
4. School of Information Science and Technology, ShanghaiTech University & Shanghai Engineering Research Center of Intelligent Vision and Imaging, Shanghai, China