Inferring Illumination Direction Estimated from Disparate Sources in Paintings
SPIE Symposium on Electronic Imaging, San Jose, CA, 2008
Abstract
The problem in computer vision of inferring the illumination direction is well
studied for digital photographs of natural scenes and recently has become
important in the study of realist art as well. We extend previous work on this
topic in several ways, testing our methods on Jan Vermeer’s Girl with a pearl
earring (c. 1665–1666). We use both model-independent methods (cast-shadow
analysis, occluding-contour analysis) and model-based methods (physical models
of the pearl, of the girl’s eyes, of her face). Some of these methods provide an
estimate of the illuminant position in the three dimensions of the picture
space, others in just the two dimensions of the picture plane. Our key
contributions are a Bayesian evidence integration scheme for such disparate
sources of information and an empirical demonstration of the agreement, or at
least consistency, among such estimates in a realist painting. Our methods may
be useful to humanist art scholars addressing a number of technical problems in
the history of art.