Adaptable drawing interpretation using object-oriented and constraint-based graphic specification

The problem of converting paper drawings into computer-based representations suitable for further use in CAD and CIM applications is addressed. While previous approaches have been able to solve this problem for certain application domains, the kernel system presented is adaptable to a wide variety of applications including engineering drawings and electronic circuit diagrams. The key elements of the approach presented are a knowledge-based interpretation process and a declarative specification language for defining meaningful graphical objects to be recognized in a drawing. The potential efficiency problems of a strictly declarative approach are overcome by automatically compiling graphic specifications into efficient procedures. The adaptability and efficiency of the kernel system are demonstrated using examples from several domains