3-DIMENSIONAL SPACE FROM OPTICAL-FLOW CORRESPONDENCE

This study considers the use of two distinct images of a number of points at which optical flow is known, to recover the relative displacement of the viewing systems and the position and motion of the points in space. The viewing systems are assumed immobile and the points rigidly moving. The problem considered here can therefore be seen as a generalization of the structure-from-motion problem as it considers both the discrete case of point correspondences and the continuous case of optical flow. A linear method is proposed based on the observation of four (or more) points. The linear system of equations resulting from this observation is solved for the relative displacement of the viewing systems. Once this displacement is calculated, the position and motion of the points in space are given straightforwardly.