Method and System of Person Identification by Facial Image

Abstract

A method to recognize a facial image is described. An input facial image is normalized by scaling and rotation angle using methods of eye pupil centers detection. The input facial image is further normalized by lighting intensity. Template images are obtained either by the processing of certain images taken from different face positions, or by a preliminary reconstruction of a 3D face model based on stereo-pair images. Using the 3D model template, facial images are generated at different rotation angles. Distances between the input facial image and the template image are calculated from the Discrete Cosine Transformation (DCT) features, defined by overlapped blocks of these images. The facial image is recognized based on these distances.

1 . A computer-based method of comparing an image with a template image, the method comprising:
 deriving a normalized image based on the image;   splitting the normalized image into rectangular blocks;   representing the set of rectangular blocks of the normalized image by a DCT (discrete cosine transform);   calculating a first distance between the normalized image and the template image based on a weighted sum of distances between corresponding blocks from the set of rectangular blocks of the normalized image and a set of rectangular blocks of the template image;   comparing the first distance to a first predetermined threshold, the first predetermined threshold indicating a degree of similarity between the normalized image and the template;   responsive to the first distance being greater than the first predetermined threshold, determining a set of overlapping blocks from the normalized image and representing the set of overlapping blocks by the DCT;   calculating a second distance between the normalized image and the template image based on a weighted sum of distances between corresponding blocks from the set of overlapping blocks of the normalized image a set of overlapping blocks of the template image; and   recognizing the normalized image based on the calculated distances.