Animation of a B-Spline Figure

Monique Nahas, Herve Huitric, and Michel Saintourens
Visual Computer, 1988

Abstract

In this paper we describe how the use of B-Spline surfaces allows lissom movements of body and face. Our method is empirical, based on a parametrical animation. It can be combined with a muscles model for facial animation as we illustrated for the speech.

Summary

The face data they worked with composes of about 70,000 digitized points that is built into a B-Spline surface. The direct manipulation is not possible because of the magnitude of the database, so a reduced set of characteristic points are selected to act as "magnets". The movements of these characteristic points constitute the set of parameters allowed to move the face. Their work, however, are largely based trial-and-error to extract suitable points and determining displacements of the characteristic points.

An interesting note in the paper is the discussion that the principal facial expressions such as joy, disgust, surprise, sadness, anger, and fear seem to be universal, and transcends culture. What varies according to culture are the rules for the release of these emotions, but not the use of muscles related to each expression.