Handling Overtraced Strokes in Hand-Drawn Sketches

Overtracing is the phenomenon in sketching of repeatedly drawing over previously drawn ink. It is a naturally appearing effect and is especially frequent in domains such as architectural drawings. Existing work in sketch recognition focuses on sketches with nonovertraced strokes. In this paper, we describe a method for generating geometric approximations of overtraced strokes in terms of primitives including lines, non-selfintersecting polylines, ellipses and arcs. Our system generates concise approximations for overtraced strokes at an early stage in sketch processing, making it possible to use these concise descriptions in higher level processing and sketch interpretation systems.