A 3-D computer is a model of the face all 44 muscles and its called an "action unit". The Dr. Huang relies to work on of psycholoists and Dr. Paul Eckam, the creater of FACS (Facial Action Coding System). Dr. Eckman classified six basic emotions suprise, anger, happiness, fear, and sadness. Then he made associated each with charatcteristic movements of the facical muscles.

Dr. Huang smiling broadly " even though individuals often show varying degrees of expression". Huang using video imagery, new emotion-recognition software tracks these movements in a real face or the painted picture of Mona Lisa. The weighting the diffeent units in the software can be even identify mixed emotions. Even each expression can be compared against the neutral face.

The humans perform the same impressive "calualtion" every single day. if we can probably tell our friend how they're feeling because by the way look on there faces. But most of us would have trouble describing each facial.