3D face modeling from stereo and differential constraints

This paper proposes a way to incorporate a priori information in a 3D stereo reconstruction process from a pair of calibrated face images. In our framework, a 3D mesh modeling the surface is iteratively deformed in order to minimize an energy function in a snake-like process. Differential information about the object shape is used to generate an anisotropic mesh that can both fulfill the compacity and the accuracy requirements. Moreover, in areas where the stereo information is not reliable enough to accurately recover the surface shape, because of inappropriate texture or bad lighting conditions, we propose to incorporate some geometric constraints related to the differential properties of the surface. These constraints can be intuitive or can refer to some predefined geometric properties of the object to be reconstructed. They can be applied to scalar fields, such as curvature values, or structural features, such as crest lines, governing their location, number, or spatial organization. We demonstrate our approach using faces.