Multiscale edge detection on range images via normal changes

A new edge detection technique based on detection of normal changes is proposed. Most of the existing range image-based edge detection algorithms base their detection, criterion on depth or curvature changes. However, the depth change-based approach does not have keen sensitivity in detecting roof (or crease) edges, and the curvature change-based approach suffers from a complicated and tedious principal curvature derivation process. Using normal changes as a detecting criterion, on the other hand, the existence of an edge can be easily detected, even when the change across a boundary is slight. Experimental results using both synthetic and real images demonstrate that the proposed method can efficiently detect both step and roof edges.