Patent ID: 7778458
Filing Date: 2010-08-17
Classification: B07C,G01N,G06K,G06T

Abstract:
1. A method executed by a programmed processor for searching knots in wood, the method comprising: photographing a piece of wood by a photographing unit; performing a first calculation comprising calculating degrees of circularity of each figure in the photographed images of the piece of wood and setting at least one figure comprising a circularity corresponding to a knot candidate; clipping a partial image including said knot candidate from said at least one figure; varying threshold levels of gray value for said clipped partial image such that an image is obtained at each of said threshold levels, said image including said knot candidate; performing a second calculation, said second calculation comprising calculating a degree of circularity and stability of said knot candidate at each of said threshold levels; identifying one of said images from said plurality of images comprising a selected threshold level, said selected threshold level corresponding to a level at which said circularity and said size stability of said knot candidate is a maximum value with respect to said circularity and said size stability values of said knot candidate in said other images; determining a configuration of said knot candidate at said selected threshold level; detecting said knot candidate as a knot when said degree of said circularity of said knot candidate is greater than a predetermined circularity degree at said selected threshold level.