When detecting a face included in an input image by use of at least two inclinations of the face to be detected, a first detection process is performed if the inclination of the face to be detected corresponds to a first inclination where a relatively high face detection probability is expected, and...http://www.google.fr/patents/US7809173?utm_source=gb-gplus-shareBrevet US7809173 - Face detection method, apparatus, and program
