Incorporating Illumination Constraints in Deformable Models

In this paper we present a method for the integration of nonlinear holonomic constraints in deformable models and its application to the problems of shape and illuminant direction estimation from shading. Experimental results demonstrate that our method performs better than previous Shape from Shading algorithms applied to images of Lambertian objects under known illumination. It is also more general as it can be applied to non-Lambertian surfaces and it does not require knowledge of the illuminant direction. In this paper: (i) We rst develop a theory for the numerically robust integration of nonlinear holonomic constraints within a deformable model framework. In this formulation we use Lagrange multipliers and a Baumgarte stabilization approach 2]. (ii) We also describe a fast new method for the computation of constraint based forces, in the case of high numbers of local parameters. (iii) We demonstrate how any type of illumination constraint, from the simple Lambertian model to more...

• Type: Conference
• Year: 1998
• Where: CVPR
• Authors: Dimitris Samaras, Dimitris N. Metaxas
• Keywords: Computer Vision, CVPR 1998, Illuminant Direction Estimation, Improved Light Estimation, Light Direction Estimation, Nonlinear Holonomic Constraints, Shape Estimation Method