Item

Abstract

The human face is capable of producing an astonishing variety of expressions—expressions for
which sometimes the smallest difference changes the perceived meaning considerably. Producing
realistic-looking facial animations that are able to transport this degree of complexity continues
to be a challenging research topic in computer graphics. One important question that remains
to be answered is: When are facial animations good enough? Here we present an integrated
framework in which psychophysical experiments are used in a first step to systematically evaluate
the perceptual quality of several different computer-generated animations with respect to real-world
video sequences. The first experiment provides an evaluation of several animation techniques,
exposing specific animation parameters that are important to achieve perceptual fidelity. In
a second experiment we then use these benchmarked animation techniques in the context of
perceptual research in order to systematically investigate the spatio-temporal characteristics of
expressions. A third and final experiment uses the quality measures that were developed in the
first two experiments to examine the perceptual impact of changing facial features to improve
the animation techniques. Using such an integrated approach, we are able to provide important
insights into facial expressions for both the perceptual and computer graphics community.