Facial Action Coding System for the Tongue

FACS (Facial Action Coding System) is an anatomically based system for describing all observable facial movements. FACS provides a very reliable description for the face upper parts but it does not for the lower parts of the face. That limits FACS from being the dominant technique in the Facial Animation field. In this paper, we proposed 12 AUs (Action Units) for the Tongue, based on tongue anatomy, following the same format Paul Ekman used in defining FACS AUs. We applied these AUs on a 3D human model using Daz Studio Pro. and compared the results with photos that have been captured for real humans performing the proposed AUs. The results were very analogous to the ones performed by the real humans. Then we used the proposed AUs to make tongue animation for a very popular tongue movement in Egypt which is called Zaghrouta. The resulted animation was very realistic and almost identical to the video taken for an Egyptian woman performing this movement. Now we are having anatomically defined and reliable action units to control the tongue and overcame FACS limitation in this area. The proposed AUs offer additional pose control dials, as add-on for the existing computer graphics software, which give the animator more control and flexibility over the tongue and new levels of dynamic movements.