Patent ID: 7724940
Filing Date: 2010-05-25
Classification: G06K

Abstract:
1. A method of determining a similarity between a target image and a reference image using a vision system included in a part mounter, the method comprising: (a) obtaining related approximation pixel-values of the reference image, wherein the related approximation pixel-values have an overall relationship between coordinates and original pixel-values f (b) obtaining target related approximation pixel-values having overall relationship between coordinates and original pixel-values of pixels of the target image; and (c) determining the similarity using the target related approximation pixel-values and the reference related approximation pixel-values, wherein operation (b) comprises: (b1) setting a polynomial equation having variables and unknown constants corresponding to the coordinates (x, y) of the pixels of the target image; (b2) completing the polynomial equation by obtaining the unknown constants of the polynomial equation under a condition that can minimize differences between the original pixel-values f (b3) obtaining the target related approximation pixel-values p