Approximation to the Fisher-Rao metric for the focus of expansion

The Fisher-Rao metric for the focus of expansion is approximated, under the assumption that the focus is estimated from correspondences between two images taken by a translating camera. The approximation is accurate if the errors in the image correspondences are small. The parameter space for the focus of expansion is sampled at a finite set of points chosen such that every point in the space is near to at least one sample point. A focus of expansion is detected by checking each sample point in turn to see if it is supported by the image correspondences. (C) 2008 Elsevier B.V. All rights reserved.