“…In literature, several researches are found as validation of the technique through the comparison with the PIV, such as Corpetti et al [6] and Liu et al [7]. Among all the computer-vision methods, the optical-flow technique is one of the mostly employed approach in this field [8,9,10], but in general, it has been widely applied to research displacement fields in solid bodies [11,12,13,14], liquid flows [15] and gas flows [16,17,18]. Optical-flow is related to the motion of visualfeatures, such as corners, edges, ridges and textures in two consecutive frames of a video scene [19,20].…”