Department of Information Engineering, University of Padova, via G, Gradenigo 6/B, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, via G, Gradenigo 6/B, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, via G, Gradenigo 6/B, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, via G, Gradenigo 6/B, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, via G, Gradenigo 6/B, 35131 Padova, Italy.