Applying human visual property in the recognition of faces, people can identify face from very far distance,even the details are vague. That means the symmetry characteristic is enough to be recognized. Human face is made up of eyes, nose, mouth and chin etc. There are differences in shape, size and structure of those organs, so the faces are differ in thousands ways, and we can describe them with the shape and tructure of the organs so as to recognize them. One common method is to extract the shape of the eyes, nose, mouth and chin, and then distinguish the faces by distance and scale of those organs (as shown in Fig.1).
The other method is to use deformable model to
describe the shape of the organs on face subtly [7].
We can tell the characteristics of the organs easily by
locating the feature points from a face image. If we
normalized the characteristics which have the
properties of scale, translation and rotation invariance,
we can normalize the faces in the database through