Shading logic: a heuristic approach to recover shape from shading

A heuristic-based algorithm known as the shading logic algorithm is proposed for recovering shape from shading. The heuristics are derived on the basis of a geometrical interpretation of the M.J. Brooks and B.K.P. Horn (1985) algorithm. An experimental evaluation was performed using synthesized objects, in particular, superquadrics. The advantage of using the superquadrics is that the shape of the objects can be varied incrementally and systematically. Despite the fact that the shading logic algorithm is heuristic based, experimental results show that the proposed algorithm has a better performance than the Brooks and Horn algorithm. In addition, the proposed approach does not seem to suffer the stability problem common to most variational-based methods