[1] School of Electronic Engineering, Info. Technology and Mathematics, University of Surrey, Guildford GU2 7XH, United Kingdom
[2] University of Brighton, United Kingdom
[3] Surrey University, United Kingdom
[4] University of Surrey, Centre of Vision, Speech and Signal Processing
[5] Aristotle University of Thessaloniki, Greece
[6] University of Cambridge, United Kingdom
[7] School of Electronic Engineering, Info. Technology and Mathematics, University of Surrey, United Kingdom
[8] University of Cambridge