Patent ID: 6614041
Filing Date: 2003-09-02
Classification: G01N

Abstract:
A method for determining the wood/bark ratio from a flow of wood material, in which the flow is illuminated in a non-flashing manner with a lighting having a color temperature, scanned along a transverse line with a video camera, the line image corresponding to the line is digitalized into pixels each of which comprise intensity information, the intensity classes corresponding to the wood and the bark are determined and the pixels belonging to each class are calculated with the help of their intensity information, and the wood/bark ratio is determined by the number of pixels situated in the different intensity classes, and at least three color channels are used the dynamics of which are each at least 10 bit and the classes are fixed at least three-dimensionally on these channels and three absolute color signals are produced, characterized in thatthe flow is illuminated in such a manner that the color temperature of the lighting is always kept stable and a bias correction is carried out to the absolute color signals R, G and B of a color probe by taking into account the response of the zero value of the actual light intensity of each channel and the absolute color signals are corrected to be relative by dividing the value of the absolute color signal of each channel with the sum (R+G+B) of the values of the signals of all channels.