Experiments with a spatiotemporal correlator

Reports on some simple experiments with a pointwise spatiotemporal correlator. The correlator is demonstrated to be potentially useful for edge and corner detection in single image frames, and for generating image motion fields from temporal image sequences. In contrast to previous proposals, the correlations described are computed for single pixels rather than for image windows. This avoids unnecessary smoothing, which for motion field estimation is particularly undesirable across occluding edges. Another novel feature of this work is that the pointwise correlations between a pixel in one image frame and those in an adjoining frame are not computed over a uniform image grid: the grid is finer for smaller image displacements, and coarser for larger ones