S. Ravindranath et Ub. Desai, AN ANALOG HOPFIELD NETWORK TO OVERCOME EXCESSIVE SMOOTHING IN SHAPE FROM SHADING, Journal of the Franklin Institute, 331B(5), 1994, pp. 587-605
The regularization term used in the cost function of the shape from sh
ading (SFS) problem is necessary to make the problem well-posed. Howev
er, it has the disadvantage of producing excessive smoothing of the su
rface even at places where the gradient of the surface slope is very h
igh. To overcome this we propose th use of a line function depending o
n the gradient of the surface slope in the regularization term. For an
analog line function. the SFS energy functions is then minimized usin
g and analog Hopfield network. For a binary line function, the SFS ene
rgy minimization problem is formulated as a combinatorial minimization
problem; the minimization is implemental using a Boltzmann machine (s
imulated annealing). Simulation results are presented to substantiate
our approach.