Facial feature measurements with photometric stereo

This paper introduces an application of photometric stereo to facial feature measurements. First, the authors propose a modified photometric stereo which reduces the size of the table and errors of the table lookup. Then, three applications are described, all of which use the gradient data obtained by the modified photometric stereo. These examples show that the photometric stereo is quite sufficient for facial feature measurements though the albedo of human face does not completely agree with the Lambertian reflectance