Face recognition (FR) offers unmatched advantages as compared to other biometrics, such as easy access or needless explicit cooperation from users, and today, it has attained the reliability and the maturity required by real applications. Despite these recent achievements, the reliability of face recognition system can still be improved, most notably with respect to large facial expression changes and to ageing. In this thesis, the aim is to address one of these issues, facial expression changes.

Specifically, the aim of this thesis is to raise some constraints on the existing 2D FR solutions thanks to 3D, thereby widening their range of application fields. These applications can include for instance FR dealing with non cooperative users who may present their face not in a neutral facial expressions (e.g. mouth opening), or even FR using images from video surveillance which can gather all the difficulties such as low resolution images, pose changes, lighting condition variations, occlusions, etc.

In this thesis, the candidate will investigate the possible contribution of 3-D to improve performances of authentication while keeping existing advantages of face recognition from 2-D images. It has been shown that using a 3D model of human face does improve 2D face recognition robustness to illumination and pose variation. Concerning expression though, its utilization is still an open question.