Surface checking often disfigures the appearance of wood treated with water-borne preservatives and treatments designed to reduce such checking have been receiving increasing attention. Progress in this area has however been slowed by the lack of a method of rapidly and accurately quantifying checking at treated wood surfaces. A software package has therefore been developed which identifies, measures and records the dimensions and numbers of surface checks in scanned images of preservative treated wood specimens. The program uses grey-scale 600 dpi TIFF images of wood specimens and operates within the data acquisition, analysis and presentation software IgorPro (Wavemetrics). Procedures within the program analyse images sequentially pixel by pixel and one row at a time searching for brightness minima (dark areas) which satisfy criteria that are characteristic of checks. A black and white (b/w) image is then produced in which probable checks are shown black on a white background. Further procedures reduce noise in the b/w image eliminating artifacts (specks of dirt) and small checks that cannot be discerned by the naked eye. The final stage of the analysis rasters through the cleaned b/w image establishing which black pixels connect to each other and identifying and labeling checks and quantifying check positions, sizes and shape. These data are then presented in a spreadsheet. Using this package it has been possible to successfully quantify checking in a range of preservative treated wood specimens that have been subjected to natural weathering. This paper describes the principal features of the software package and presents preliminary data from analysis of treated and weathered specimens. The advantages of the system for quantifying checking in preservative treated wood as well as its limitations are discussed.

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