Design, Transformation, and Animation of Human Faces

N. Magnenat-Thalmann, H. T. Minh, M. de Angelis, and D. Thalmann
Visual Computer, 1989

Abstract

Creation of new human faces for synthetic actors is a tedious and painful task. The situation may be improved by introducing tools for the creation. Two approaches are discussed in this paper: modification and edition of an existing synthetic actor using local transformations; generation of new synthetic actors obtained by interpolation between two existing actors; creation of a synthetic actor by composition of different parts. This paper also describes the methods usied in the facial animation of synthetic actors who change their personalities from one person to another. This means that our purpose is to transform one character into another, and also to transform the animation at the same time. The method has been completely implemented and integrated into the Human Factory software.


Summary

To interpolate between two faces, we can either make facets appear or disappear in order to obtain a good correspondence, or reorganize (resample) both figures by creating a structure of facets common to both face meshes. The approach taken by the paper is the latter.

The faces are controlled at three levels of interaction. The first level allows access to facial parameters to define the basic deformations. The second level abstracts a set of parameters to form expressions to mimic phonemes or shape expressions. The third level controls the time at which certain expressions are expected of a digital actor.