Subpixel Accurate Edge Coordinates Deduction Of Circular Object In Machine Vision
Chandesh Sayaji Ghule, Dr. M.S. Panse
Keywords: subpixel accuracy, edge pixels, subpixel coordinate space
Abstract: Automation in industries needs faster approach for object inspection. So, for such applications we generally go for machine vision. But, accuracy is also very important. Pixel accuracies are sometimes insufficient to describe the exact dimensions of an object or fall short. In such cases, there is an urgency to device a method which will take care of subpixel accurate measurements. Here, we have come up with such a novel approach to find subpixel accurate edges of a circular object. This we achieved by exploiting local pixel intensity values. Subpixel order of 20th was easily achieved i.e. measurements up to 20 times that of a pixel could be made. We achieved measurements up to 30 microns.
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