A Fast and Accurate Approach to the Computation of Zernike Moments

This paper presents a fast and accurate approach to the computation of Zernike moments from a digital image. Exact Zernike moments are computed with these fixed exact coefficients. The digital image is transformed to be inside the unit circle, where the transformed image is divided into eight parts. Based on the specific symmetry or anti-symmetry about the x-axis, the y-axis, the origin, and the straight line y = x, we can generate the Zernike basis functions by only computing one eighth of the image. Inside the unit circle, the image information is not lost. Experimental results show that the proposed method can reduce significantly the computation operations, so the time can be reduced to just one eighth of the original computation methods.