To the problem of shape from shading

the existence of self shadowed regions in the image is one of the factors which could cause the deformation to the final 3D reconstructed surface and it should be coped with in its special way. In the paper

a set of method is presented

which is composed of shadow region segmentation

coordinate system transmission

and the parabolic data interpolation. The method is based on the principle that the distortion of self shadow should be enclosed within its region

in order not to destroy the global reconstructed shape. The light source projected system is introduced

which is defined on the image plane and the direction of light source. This can greatly simplify the problem

and makes it possible to analyze the self shadowed data sections in the image vow by vow. And the primary goal could be achieved by recovering the depth gaps across the self shadowed data sections. Meanwhile

the height incremental values at each shadowed pixel could be estimated by parabolic interpolation

and makes the recovered shadowed shapes connect with other regions smoothly. It has demonstrated that

this proposed method could improve the reconstructed 3D shapes from shading efficiently.