Automated measurement of checks at wood surfaces

Surface checking often disfigures the appearance of wood, but methods of accurately and rapidly measuring checking in wood are not well developed. This paper describes the principal features of a software package that measures the dimensions and numbers of checks in scanned images of weathered wood surfaces. Procedures within the program analyze images searching for brightness minima that satisfy criteria that are characteristic of checks. A black-and-white image is then produced in which checks are shown black on a white background. Further procedures reduce noise in the black-and-white image eliminating artifacts and small checks invisible to the naked eye. The final stage of the analysis identifies and labels checks and quantifies their positions, sizes and shape. Using this software it has been possible to successfully quantify checking in a range of preservative treated wood specimens that have been subjected to natural weathering. The advantages of the system for quantifying checking in wood as well as its limitations are discussed.