Anatomical considerations in facial motion capture

Facial performance capture has been enabled unquestionably by significant technological advances in three dimensional motion capture and modeling. Yet from a critical artistic perspective, the question remains: why do performances so generated frequently read as lifeless or "zombie-like"? While improvement in the density of collection and integration of data will undoubtedly refine the quality of the motion capture product, the anatomical answer to this artistic question goes beyond refinement of quasistatic simulation schemes and finite elements methods to address several basic principles of human facial anatomy, expression and ontogeny (development from juvenile to adult). The latter consideration is especially important in issues involving inter-individual scaling, because translation of facial performance onto characters of differing proportions presents one of the greatest challenges to the utility of motion capture.