Department of Psychology, Durham University, Science Site, Durham, United Kingdom.|Department of Electronic Electrical and Systems Engineering, School of Engineering, University of Birmingham, Edgbaston, Birmingham, United Kingdom.|School of Information and Electronics, Beijing Institute of Technology, Beijing, China.|College of Electronic Science and Engineering, National University of Defense Technology, Changsha, China.|Department of Electrical & Computer Engineering, The Ohio State University, Columbus, Ohio, United States of America.|School of Information and Electronics, Beijing Institute of Technology, Beijing, China.|Department of Computer and Communication Systems Engineering, Universiti Putra Malaysia (UPM), Serdang, Selangor, Malaysia.|Department of Electronic Electrical and Systems Engineering, School of Engineering, University of Birmingham, Edgbaston, Birmingham, United Kingdom.|Department of Electronic Electrical and Systems Engineering, School of Engineering, University of Birmingham, Edgbaston, Birmingham, United Kingdom.|World Access for the Blind, Placentia, California, United States.|Department of Electronic Electrical and Systems Engineering, School of Engineering, University of Birmingham, Edgbaston, Birmingham, United Kingdom.