In Intelligent Biometric Techniques in Fingerprint and Face Recognition , eds. L.C. Jain et al., publ. The task is difficult because of image variation in terms of position, size, expression, and pose. The system collapses most of this variance by extracting concise face descriptions in the form of image graphs . Image graph extraction is based on a novel approach, the bunch graph , which is constructed from a small set of sample image graphs.
Recognition is based on a straightforward comparison of image graphs.