3D-reconstruction of faces: Combining stereo with class-based knowledge

The recovery of the threedimensional structure of faces with conventional stereo methods still proves difficult. In this paper we introduce a higher order constraint based on linear object classes, which supplies a standard stereo algorithm with prior knowledge of the general structure of faces. This constraint has been learned by exploiting the similarities between 200 faces in a database and is represented in a morphable face model. This combined approach has been tested and compared against an already existing method for estimating depth information using only prior knowledge and against the standard stereo algorithm