| Popis: |
The instantaneous three-dimensional velocity field of a moving surface can be computed from a sequence of dense range data sets. Here we discuss the computation of the underlying motion constraint equation. This involves the evaluation of derivatives of the depth coordinate with respect to the other world coordinates. As these are not evenly sampled the sampling has to be taken into account explicitly. We quantitatively compare four methods to compute derivatives based on the validity of the resulting constraint equation. |
