Incremental acquisition of knowledge about layout structures from examples of documents

Document image analysis systems often utilize the knowledge about layout structures to extract layout objects labeled logically. However, the lack of the facility for knowledge acquisition limits the applicability of the systems. The authors propose a method of acquiring knowledge for document image analysis. Given examples of document images and their layout objects labeled logically, the method generates and modifies the knowledge. The method is incremental so that the knowledge can be efficiently modified using additional examples. Counterexamples generated as errors obtained from the analysis of an example image can also be reflected into the knowledge so that the system may no longer generate the errors. Experimental results on both knowledge acquisition and the analysis using the acquired knowledge are also presented