Synthesis of Facial Caricature Using Eigenspaces

摘要

A facial caricature expresses features of an individual face compactly and effectively. It is used in newspapers, magazines, home pages, and also used to represent an anthropomorphic agent and so on. This paper presents a method of synthesizing a caricature having higher flexibility in controlling individual shape features of various parts of a face, as well as features of arrangements and inclines of these parts. Firstly, an eigenspace is calculated for contour shape of each facial part such as the eyebrows, eyes, and mouth. In addition, an eigenspace for arrangements of various facial parts is obtained. Next, differences of the shapes and arrangements of the facial parts with the average face are calculated and then the orthogonal expansion to the basis vectors (eigenvectors) is carried out on these differences. Magnifying powers are determined according to the coefficients obtained by the orthogonal expansion and an emphasizing procedure is performed on eigenvectors. The difference between the slope of each facial part of the average face and that of an input face is emphasized using a quadratic function. A final caricature can be obtained by adding the average shape, average arrangement and average slope to these results. The effectiveness of the proposed caricature synthesis method is verified by subjective evaluation tests on synthesized facial caricatures.