☆ Editor's Choice Articles are invited and handled by Editorial Board committee. This paper has been reco Philippos Mordohai. ☆☆ This work was carried out while both authors Group, Toshiba Cambridge Research Laboratory, Cambri The research was fully funded by Toshiba Research Eur ⁎ Corresponding author. Tel. : +44 7900023260. E-mail addresses: g.vogiatzis@aston.ac.uk (G. Vogiat carloshernandez@google.com (C. Hernández).