Research Article

Perceptually Valid Facial Expressions for Character-Based Applications

Table 1

Examples of action units for universal expression of joy and sadness [2].

EmotionAction units

JoyEyelid tightened
Cheeks raised
Brows slightly lowered
Wrinkles around eyes
Lip-corners raised and stretched

SadnessUpper eyelid lowered
Lower eyelid raised
Inner brows raised
Lip corners lowered
Lower lip raised slightly
Cheeks raised