Research Article
Perceptually Valid Facial Expressions for Character-Based Applications
Table 1
Examples of action units for
universal expression of joy and sadness
[
2].
| Emotion | Action units |
| Joy | Eyelid tightened | Cheeks raised | Brows slightly lowered | Wrinkles around eyes | Lip-corners raised and stretched |
| Sadness | Upper eyelid lowered | Lower eyelid raised | Inner brows raised | Lip corners lowered | Lower lip raised slightly | Cheeks raised |
|
|