Simple direct computation of the FOE with confidence measures

A direct method is proposed for locating the focus of expansion, based on simple parallel computations in selected regions of the image; each is a circular patch around an estimated focus of expansion (FOE). Simple computations allow determining the direction from the estimated to the true 400FOE. The best estimate of the intersection of the so-called FOE constraint lines for each region gives the location of the FOE. Some analysis allows a confidence measure to be assigned to the information from each local region, in order to give more weighting to the most reliable data. Hence, the FOE can be located with more accuracy, even when the data from various local regions lack sufficient information