Temporal Control Issues

This section explores the problems associated with temporal issues in facial animation, since variations in this dimension alone can alter the semantics of the expression. For example, if an expression is slowly animated from neutral to happy, the resulting expression may be interpreted as insincerity rather than happiness. Consequently, script-driven systems, or natural language systems driven from textural input, have to integrate the temporal issues of motion.

It is important to differentiate three aspects of time for facial animation:

1. The timing of the onset, apex and offset for an expression.

2. Internal synchrony with speech, for example, intonation and emotion.

3. Inter-synchrony to take into account interpersonal interactions.

• Timing of Facial Action
• Facial Expressions, Speech and Emotion
• Dialogue Situation