Patent Document ID: 9116135
Application ID: 13469193
Patent Status: 1

Claim One:
1. A method for detecting visual uniformity of a surface having a pattern comprising: capturing a surface image of the surface to be detected, wherein said surface image contains N grayscale pixels and wherein said N is a positive integer; compiling a statistic containing pixel amount of each grayscale value and if said pixel amount of respective ones of the grayscale values is smaller than a predetermined amount, discounting said pixel amount of the respective ones of the grayscale values to leave in said surface image only M grayscale pixels after discounting, wherein said M is smaller than said N; selecting f×M first fraction of pixels having smallest grayscale value content, based on a selection ratio f, said first fraction of pixels defining a pattern zone, and calculating a mean of the grayscale values within said pattern zone; selecting f×M second fraction of pixels having biggest grayscale value content, said second fraction of pixels defining a background zone, further calculating a mean of the grayscale values within said background zone; and determining the visual uniformity of the surface based on respective mean grayscale values of said pattern zone and said background zone comparatively within said captured surface image.