Fig. 5

Symmetric mean absolute percentage error or SMAPE (left column) and edge geometry (right column) generated by a 5×5 chamfer kernel. a Euclidean weights, a=1, \(b=\sqrt {2}\), and \(c=\sqrt {5}\). b Euclidean weights, a=1, \(b=\sqrt {2}\), \(c=\sqrt {5}\), and r=1. c Our weights, a=0.9865, \(b=\sqrt {2}\), and c=2.2059. d Our weights, a=0.9865, \(b=\sqrt {2}\), c=2.2059, and r=1