Analysis on principle deviation of sub-pixel Zernike moments operator with 7x7 masks

Zernike moments edge operator with 7x7 maskes is chosen as research object in this paper, principle deviation character of this operator caused by edge model is present, modified formula of edge translation 1 is deduced and given, it shows that the principle deviation is zero when edge lie in center pixel in a sample window, for another case, the edge translation 1 should be verified by modified formula of principle deviation. utilizing 7x7 masks to replace original Zernike moments operator with5x5 masks, the location accuracy of operator can be improved partly, but the masks Computer still adopted ideal step edge masks, because of the principle deviation in the masks exists as before. The paper is based on problem, conducts theory analysis about principle deviation of the operator, and Presents modified formula of edge range, further more, improves the location accuracy of the operator.