Patent ID: 7601978

Claim:
An active imaging system for determining the smoothness of the surface of a fabric, the system comprising: a support for holding the fabric in a plane; a single-line laser projector positioned at an angle above said plane, the single-line laser projector capable of directing radiation onto at least one portion of the surface of the fabric; a single range camera positioned above said plane, the range camera capable of capturing at least one range image of the at least one portion of the surface of the fabric based on the radiation from only the single-line laser projector, the range image including a topographic map including height differences of a plurality of points on the surface of the at least one portion of the surface of the fabric; and a processor that obtains the range image, and determines the smoothness of the surface of the fabric using an algorithm that incorporates one of a facet model and a plane-cutting method, wherein, the smoothness of the surface is determined by: generating a plurality of parallel planes that intersect the surface at a plurality of range levels, recording an intersection area with the surface for each of the parallel planes, calculating a category of a plurality of categories for each of the intersection areas, the plurality of categories including an area under the curve of the intersection area versus the range level, and determining a degree of smoothness for the surface.