ON THE CORRESPONDENCE PROBLEM FOR WIDE ANGULAR SEPARATION OF NONCOPLANAR POINTS

We describe a solution to the problem of stereo matching for non-copla nar points and wide angular separation of uncalibrated cameras. The im age projections of four corresponding coplanar points, with no three c ollinear, are assumed to be known. The 'virtual image' that results by 2D warping of the first image towards the second one according to the homography of a known plane in 3D is used. Then, instead of trying to match points between the two images, we exploit the fact that all cor responding points between the virtual and the second image are in alig nment. It is shown how the matching problem can be cast into an optimi sation one, and a cost function for evaluating each possible solution is derived. For increased robustness to outliers a Hough-Transform-lik e algorithm is suggested for obtaining the optimal solution, and a ran domised scheme is shown to be efficient for practical applications. Ex perimental results on both synthetic and real data are also included. (C) 1998 Elsevier Science B.V.