Synthesising continuous-tone caricatures

Abstract A series of tools has been developed to synthesize full colour photographic quality facial caricatures. Real faces, photographs or single-frame video films are frame-grabbed and the position of (186) key points around external and internal features are interactively defined. Following procedures of Brennan 7,8 the 2D Cartesian coordinates of each feature point are compared with those of an average for many faces; differences in positions are exaggerated (to produce caricature data sets) or reduced (giving ‘anticaricature’ data sets). Line-drawing representations of faces and their caricatures are formed by linking appropriate feature points. To produce continuous-tone caricatures, the original and caricature images are resolved into (340) adjacent triangular tessellations. Rendering of the final image is accomplished by mapping the pixel values (grey-scale or colour) from each source triangle in the original image to the corresponding triangle in the caricature image. The caricatures not only provide amusement, but can be used as stimuli in psychological investigations into the representation of faces in human memory.