TIME-VARYING IMAGES - THE EFFECT OF FINITE RESOLUTION ON UNIQUENESS

A classical paper by R. Y. Tsai and T. S. Huang (IEEE Trans. Pattern Anal. Mach. IntelligencePAMI-6, 1984) establishes the result about the uniqueness of motion parameters in image sequences: "Given the image correspondences of eight points in general position, the motion parameters are unique." In this correspondence, we use examples to illustrate that the theorem does not hold if finite resolution is taken into account. We also bring out the robustness issue for any possible algorithm. In fact, we show that, given the image correspondence of eight points in two views, if 10% error in the motion parameters is not acceptable, then no robust algorithm that uses slant, tilt, or Eulerian angles can be found under the worst case analysis. Furthermore, we suggest that a rotational matrix should be used to test the robustness of any potential motion algorithm. © 1991.