Incorporating illumination constraints in deformable models

Abstract

We present a method for the integration of illumination constraints within a deformable model framework. These constraints are incorporated as nonlinear holonomic constraints in the Lagrange equations of motion governing the deformation of the model. For improved numerical performance we employ the Baumgarte stabilization method. Our methodology is general and can be used for a broad range of illumination constraints. This approach avoids commonly used approximations in shape from shading, such as linearization, and the use of partial differential equations, which require initial boundary conditions. Furthermore, global and local parameterizations of the deformable models allow an improved estimation of shape from shading. We demonstrate this improvement over previously used approaches through a series of experiments on standardized sets of real and synthetic data.