In original Zernike moments subpixel edge operator, ideal step edge model is chosen for calculating four parameters of a pixel point, and therefore principle deviation is caused by edge model. In order to discuss the effect of principle deviation on edge location, sampled edge model is chosen for calculating edge parameters, principle deviation of edge translation l is derived based on Zernike moments edge detection theory, and modified formula of l is given for Zernike moments operator with masks of 5×5 size. Both theory analysis and testing result demonstrate that principle deviation is zero when edge translation l is limited in central pixel of a sampled window. In another case, the modification of l should be considered, which results in edge location accuracy of non-subpixel level for this subpixel edge operator.
QU Ying-dong LI Rong-de YUAN Xiao-guang HUANG Hong-jun LI Chen-xi
＜正＞Under high pressure that is more than lGPa,the grain growing process of Zinc-Aluminium（ZA） alloy is difficu...
~* Qu Yingdong Li Rongde Bai Yanhua Li Runxia Yang Hongwang Wang Ruichun Key Laboratory for Light Metal Material and Engineering of the Education Department of Liaoning Province
