Clustering method and system, corresponding apparatus and computer program product

Image processing circuitry processes image frames in a sequence of image frames, for example, to identify objects of interest. The processing includes filtering motion vectors associated with a current image frame, grouping the filtered motion vectors associated with the current image frame into a set of clusters associated with the current image frame, and selectively merging clusters in the set of clusters associated with the current image frame. At least one of the filtering, the grouping and the merging may be based on one or more clusters associated with one or more previous image frames in the sequence of image frames. Motion vectors included in merged clusters associated with a previous frame may be added to filtered motion vectors before grouping the motion vectors in the current frame.