ABSTRACT
The analysis of faces has a long history, and exactly how the face reflects human emotional states has concerned some noted scientists. One of the first published investigations of facial expression was by John Bulwer in the late 1640s [Bulwer 48, Bulwer 49]. He suggested that one could not only lip read but also infer emotional states from the actions of muscles. Subsequently, in the later part of the nineteenth century, Charles Bell, Duchenne de Boulogne, and Charles Darwin all applied themselves to a more rigorous investigation of facial expression. In the more recent past, Hjortsjo¨ and Paul Ekman applied some further classification to face actions. This chapter reviews some of key aspects of face analysis.
