4. The method of claim 3 , wherein the predetermined distance can be size of 30 pixels or other suitable number of pixels.
3. The method of claim 1 , wherein step (b) further comprises the steps of: (1) calculating a coordinate value of the left eye and a coordinate value of the right eye of the match facial image and the reference image; (2) calculating an angle of a virtual straight line from the left eye to the right eye with respect to a virtual horizontal line; (3) rotating the match facial image and the reference image with their individually calculated angles in order to dispose the virtual straight line to be parallel to the virtual horizontal line; (4) calculating a distance between the left eye and the right eye based on the coordinate values thereof; and (5) either zooming in the match facial image and the reference image if the distance is less than a predetermined distance or zooming out the match facial image if the distance is greater than the predetermined distance.