A robust drawing recognition system based on contour shape analysis

A novel drawing recognition system which can be efficiently applied to degraded drawings with many line breaks, dimmed lines, and characters touching a line is proposed. The system is capable of both obtaining accurate line approximation and extracting the network structure of drawings. A three-layered intermediate description of a drawing image is employed for low-quality drawing recognition. A robust line extraction technique based on the contour curvature has been developed for this intermediate description. The proposed technique is designed for small-scale hardware implementation