Enhancement of the Computer Lumber Grading Program to Support Polygonal Defects

Abstract

Computer grading of hardwood lumber promises to avoid regrading of the same lumber because of disagreements between the buyer and the seller. However, the first generation of computer programs for hardwood lumber grading simplify the process by modeling defects on the board as rectangles. This speeds up the grading process buy can inadvertently put a board into a lower grade because rectangular approximation can cause clear board surface area to be lost. This paper presents a polygonal computer lumber grading program that models the defects on the boards as polygons, thereby making the grade determination process more accurate. The grading program presented herein allows species-independent rules and considers both faces of the board in the grading process. The approximation of defects as polygons does result in an increased amount of processing time, which can be readily offset with the fast and inexpensive computers that are now available.

Citation

Klinkhachorn, Powsiri; Kathari, R.; Yost, D.; Araman, Philip A. 1993. Enhancement of the Computer Lumber Grading Program to Support Polygonal Defects. Forest Products Journal. 42(10): 41-46.