A general aperture problem for direct estimation of 3-D motion parameters

The necessary and sufficient conditions that an object should satisfy so that motion can be uniquely determined by a direct method are discussed. This direct method, based on the temporal-spatial gradient scheme, can estimate the three-dimensional (3-) motion parameters of a rigid moving object from an image sequence, by utilizing depth information of the object. It is shown that the 3-D motion cannot be uniquely determined for only eight kinds of objects with special geometric structure and surface pattern.<
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