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A method for extracting the motion parameters of several independently moving objects from displacement field information is:ncribed. The method s based on a generalized Hough transform technique. Some of the problems of this technique are addressed and appropriate solutions are proposed. A modified multipa Hough transform approac has been implemented, where in each pass windows are located around objects and the transform is applied only to the displacement vectors contained in these windows. The windows are determined by the degree to which the displacement field iu locally inconsistent with previously found motion transformadons. Thus, the sensitivity of the Hough transform to local events is increased and the I motion parameters of small objects can be detected even in a noisy displacement field.-W also usesa multi-resolution scheme in both the image plane and the parameter space and thus redue, the computationa cost of the technique. The method is demonstrated by experiments " on artificial imags with four parameters of 2-1) motion: rotation, expansion and translation in both axes