1. National Automotive Innovation Centre, IV sensor group, WMG, University of Warwick, Coventry, U.K.
2. Department of Computer Science and Engineering, Lehigh University, Bethlehem, PA, USA
3. Center for AI Research (CAIR), University of Agder (UiA), Grimstad, Norway
4. Visual Learning and Intelligent Systems (VLIS) Lab of Artificial Intelligence Thrust, Hong Kong University of Science and Technology, Guangzhou, China