TOWARDS AN AUTONOMOUS SYSTEM FOR ORIENTING DIGITAL STEREOPAIRS

We present a method to automatically compute the orientation of digital stereopairs. The system that we developed is based on feature-based, hierarchical matching combined with precise point determination. We use the LoG operator to determine zero crossings which we then match in the psi-s domain. No assumptions are required because the psi-s representation is rotation and scale invariant. In order to obtain maximum possible accuracy for corresponding points, a precise point matching scheme is employed. With the approximations obtained from matching zero crossings, corresponding points with sub-pixel accuracy are determined by using the Forstner interest operator combined with area correlation. The orientation parameters are computed by a rigorous bundle adjustment with blunder detection. The detailed description of our approach is followed by an example. Finally, we summarize results obtained with four different stereopairs.