The concept of matching parallelepiped and its use in the correspondence problem

In this paper, the concept of matching parallelepiped (MP) is presented. It is shown that the volume of the MP can be used as an additional measure of 'distance' between a pair of candidate points in a matching algorithm by relaxation labeling (RL). The volume of the MP is related with the epipolar geometry and the use of this measure works as an epipolar constraint in an RL process, decreasing the efforts in the matching algorithm, since it is not necessary to explicitly determine the equations of the epipolar lines and to compute the distance of a candidate point to each epipolar line. As at the beginning of the process the relative orientation (RO) parameters are unknown, an initial matching based on gradient, intensities and correlation is obtained. Based on this set of labeled points the RO is determined and the epipolar constraint included in the algorithm. The obtained results shown that the proposed approach is suitable to determine feature-point matching with simultaneous estimation of camera orientation parameters even for the cases where the pair of optical axes are not parallel.