Method for measuring the waviness of a recorded surface shape with a virtual sphere

Method for examining digitally acquired images of surfaces for their smoothness or ripple content. According to the method a virtual sphere (5) of a chosen diameter (6) is swept over one or both sides of the digitally recorded surface. The points at which the sphere does not contact the surface are recorded. Thus recesses (4) as well as ridges can be detected. The invention also relates to a corresponding use of the method for examination of tunnel or pipe surfaces in which surface images are obtained using photogrammetry or laser imaging.