Non-Photorealistic Computer Graphics Library

Human Facial Illustrations: Creation and Evaluation using Behavioral Studies and Functional Magnetic Resonance Imaging

Author(s): Bruce Gooch.
PhD Thesis: University of Utah, July, 2003.
[BibTeX]

Abstract:
This dissertation presents: a method for creating black-and-white illustrations and caricatures of human faces from source photographs; and series of perceptual studies aimed at evaluating the effectiveness of the resulting images relative to photographs. The illustrations are generated by superimposing two images: a thresholded image of the output of a computational brightness model, and a thresholded luminance image. In addition, a new interactive technique is demonstrated for deforming images of faces to create caricatures that highlight and exaggerate representative facial features. The photographs and black-and-white illustrations are evaluated via psychophysical studies to assess speed and accuracy in learning and recognition tasks. These studies show that the facial illustrations and caricatures generated using these techniques are as eective as photographs in the recognition tasks. In the learning studies, tasks involving illustrations or caricatures were performed significantly faster than the same tasks were performed with photographs. The recognition invariance effect is used as an experimental probe in a functional magnetic resonance imaging (fMRI) experiment. The results of this experiment indicate that viewers may process illustrations differently from photographs.