A fast method for identifying graphical objects in large engineering drawings

Document processing and understanding is important for a variety of applications such as office automation, creation of electronic manuals, online documentation and annotation etc. However the understanding and identifying of graphical objects in large engineering drawings which often can be of the order of 10000×10000 pixels using traditional methods can be a very challenging and time consuming task due to the sheer size. We describe a method that circumvents that by using a hierarchical top-down approach for recognizing graphical objects. The speedup is almost of the order of 1000 and this is achieved by following a strategy that exploits the characteristics of such diagrams such as low pixel density