8. The computer-implemented method of claim 7 wherein, in training CNN level n, the faces images used as input to the 1st shared layer are clipped from a common set of face images but constitute larger clips of the face images as n increases from 1 to N.
7. The computer-implemented method of claim 1 wherein, in training CNN level n, a size of the input to the 1st shared layer increases as n increases from 1 to N.