Method and tool for surface texture evaluation

Abstract

Texture of a surface, for example concrete, is evaluated by capturing images of the surface facing the surface in a direction of an orthogonal axis extending perpendicularly from the surface while sequentially projecting light onto the surface from each of four light source positions spaced circumferentially about the orthogonal axis. A specularity condition is determined to exist in one of the four images by comparing intensities of the images directly with one another. If a specularity condition exists, three images of the four images which are least affected by specularity are used to determining a surface gradient of the surface.