Illumination normalization of face images with cast shadows

We propose a method for extracting and combining small-scale and large-scale illumination insensitive features for face recognition that can work even in the presence of cast shadows. Although several methods have been proposed to extract such features, they are not designed to handle severe lighting variation on a face and thus fail to work if cast shadows are present. In this paper, we extend quotient image-based illumination normalization by explicitly taking cast shadows into account so that illumination insensitive large-scale features can be obtained. The experimental results show that the proposed method achieves favorable normalization results under difficult illuminations with cast shadows.