earticle

영어

During the last decades, Due to the advances in Information technology and communication and increase in volume of printed documents in many applications, document image databases have become increasingly important. Document Images are documents that normally begin on paper and are then via electronics scanned that move towards a paperless office and stored documents as images. Document Image retrieval is one of an important research area in the field of document image databases. Many approaches come in for indexing and retrieval document images. Traditionally, Optical character recognition (OCR) has been used for completely convert the manuscript to an electronic version which can be indexed automatically. Then, Keyword spotting has been proposed for indexing document image retrieval. Keyword spotting method has lower cost than OCR. But there are some problems in both of methods for indexing document images with non-text components. Three approaches have been presented to solve this problem, Signature based approach, layout structural and logo based approach. In this paper we proposed a framework for classify document image retrieval approaches, and then we evaluated these approaches based on important measures.