A Differential Displacement Estimation Algorithm With Improved Stability
Matthias Bierling · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1986
A new differential displacement estimation algorithm for television sequences is presented. It minimizes the local mean squared displaced frame difference rather than maximizing the local cross correlation of displaced frames, as it can be shown that there is frequently no correspondence between the cross correlation peak and the actual displacement of a moving object. The algorithm is applied iteratively, i.e. in each step of iteration the resulting estimate of the displacement vector serves as an initial guess for the next step. Compared to known techniques stability is improved by introducing a more accurate two-dimensional image model. The approximation of spatial gradients as an average of spatial differences of two successive frames yields an increased accuracy of the displacement estimate.