WORK > Facial Expression: Illustrations and Animations

Facial Expression:
Illustrations and Animations

With the most commonly used Action Units (AU’s) from the Facial Action Coding System (FACS) illustrated, I could now use all these AU’s to combine them into full face expressions. I’ve attempted to make combinations that can be interpreted as expressions of 6 big emotions: anger, disgust, happiness, sadness, surprise and fear. I say attempted, as there is not really a standard for what the different emotions look like. Also, because the illustrations of the AU’s show a strong form of the movements, the full expressions can look a bit extreme and could be much more subtle.

Anger

Starting of with anger. Mostly characterized by the brow moving down and in (AU 4). The expression can be accompanied by ‘thinning’ (AU 23) and tightening (AU 24) of the lips, as well as flaring of the nostrils and tightening of the eyelids.

Action Unit 4: Brow Lowerer Illustration

Action Unit 7: Lid Tightener Illustration

Action Unit 23: Lip Tightener Illustration

Action Unit 24: Lip Pressor Illustration

Disgust

Then there is the expression of disgust. The most important parts of this expression are the pulling up, and wrinkling of the nose (AU 9) and the raising of the upper lip (AU 10) (which does not necessarily part the lips, although it does here, as it makes the expression stronger (or exaggerated)). Here the expression is also accompanied by the eye lid tightener.

Action Unit 9: Nose Wrinkler Illustration

Action Unit 10: Upper Lip Raiser Illustration

Happiness

Next is happiness. The smile is mainly a combination of the lip corner puller (AU 12) and the cheek raiser (AU 6). Fake smiles often only show the corners of the mouth movement, missing the ‘smiling eyes’ movement (AU 6 is difficult for most people to do voluntarily).

Action Unit 6: Cheek Raiser Illustration

Action Unit 12: Lip Corner Puller Illustration

Facial Expression: Happiness Illustration

Sadness

The expression of sadness is made by the raising (AU 1) and tightening (AU 4) of the inner brow, as well as raising the cheeks (AU 6) (which is, interestingly, just as important here as in the smile expression) and, maybe the most recognizable, the corners of the lips pulling down (AU 15).

Action Unit 1: Inner Brow Raiser Illustration

Action Unit 15: Lip Corner Depressor Illustration

Surprise

Next on the list is surprise. The expression of surprise is characterized by an overall lengthening and opening up of the face. Both the inner (AU 1) and outer (AU 2) parts of the brow are raised, the upper eyelid is raised (AU 5), the lips are parted (AU 25) and the jaw drops down (AU 26).