Robust multiresolution computation of optical flow

This paper presents an algorithm that provides good estimates of the optical flow at motion discontinuities and occlusion regions based on the least-median-squares robust estimator. The use of a multiresolution scheme enables optical flow to be computed for objects with large motions. A movable overlapping neighbourhood strategy eliminates block-effects and also deals with cases of the local neighbourhood straddling regions of two or three motions. Results for both synthetic and real image sequences are presented. A quantitive comparison with the matching technique of Anandan (1989) and the differential technique of Odobez and Bouthemy (see Proceedings of 7th European Conference on Signal Processing, 1994) shows that the proposed algorithm gives much lower angular and absolute errors.