Department of Information Engineering, University of Padova, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, 35131 Padova, Italy.