Bark can sometimes be planed smooth. When a board measures full thickness at the smooth bark location but the grading inspector calls it wane -- GradeScan must also. The White Fir board image below shows what happens when the board is inspected by a geometric-only scanner. The green lines separate the board in regions of full thickness and less than full thickness. The geometric-only scanner does not provide a complete wane solution.
The image below shows the results of GradeScan's Smooth Bark Finder. Additional defect boxes are placed over the regions of smooth bark. GradeScan's multiple sensors are able to combine the geometric profile with the surface texture and color to classify bark areas correctly.
The result is that GradeScan finds the smooth bark and includes it as wane as required.