Determination of Changes in Appearance of Aged Lumber Surfaces by Image Characteristics

Abstract

Changes in appearance of every product by the aging are inevitable. Such changes are considered as the deterioration easily connecting to negative impressions to various products. On the other hand, the changes in the appearance of wooden products by the aging may create new aesthetic values such as “antique” and “vintage”. The objectives of the present study are to extract image characteristics related to the change in the appearance of lumber surface caused by the aging and to investigate relationships between them and sensory evaluation or attractiveness. Twenty-five quasi-aged wood specimens with 300 mm square were prepared by a skilled painter’s techniques. Digital image data with the true chromatic information of the specimens were captured by an imaging spectrometer and two kinds of image analyses were applied to the data. Forty university students evaluated the appearance of the specimens subjectively such as “antiquity” and “aesthetics by aging”, and the eye movements of another fifteen university students observing the specimens were recorded using an eye tracker. The surface lightness and its variation strongly affected the subjective antiquities of the specimens. The eye tracking revealed that the participants tended to gaze frequently at characters of a specimen surface such as distinct flat grain's vertexes or dirty stains.