Non-visible Deformations
نویسندگان
چکیده
Abs t r ac t . The number of non isomorphic solutions of the eikonal equation can be infinite. We show that there can exist a whole family of non isomorphic solutions, indexed by a continuous parameter. This implies, first, that the general problem of shape from shading can be ill-posed when no additional condition on the shape is imposed. This is in contradiction with what is sometimes stated in the literature of shape from shading. Furthermore, this implies that there can exist non visible deformations of a given surface, i.e., continuous deformations of the surface which do not modify the image.
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