Fourier-based Separation Technique for Shape Grading of Potatoes Using Machine Vision

Abstract

A Fourier-based shape separation method was developed for shape grading of potatoes using machine vision for automated inspection. The relationship between object shape and its boundary spectrum values in Fourier domain was explored for shape extraction. A new and fast method of using Greens theorem and boundary Fourier coefficients was given for estimating elongation of an object. A shape separator based on harmonics of the transform was defined for potato shape separation. Tests showed the shape separator was effective and efficient for difficult shape separation. The machine vision system developed has a great potential to assist humans for automated potato grading.