Information Processing from Document Images

Analysis of document images for information extraction has become very prominent in recent past. Wide variety of information, which has been conventionally stored on paper is now being converted into electronic form for better storage and intelligent processing. This needs processing of documents using image analysis algorithms. Document image analysis differs from the conventional image processing in its format and the information content. Document images are usually rich in formally presented information. The subjectiveness associated with the natural image analysis is not therefore present in the document images. Information in these images is more structured, and presented in a natural language with the help of a grammar and a script. Consider an image of a document page as shown in Figure 1(a). This contains text blocks and images. Text blocks can be paragraphs of text in various fonts and sizes, titles or captions. Extracting information from the image (graphics block) is difficult compared to that from the text block. A text block can be converted to an editable text, if the constituent script, font, character etc. can be recognised. This recognised text can provide useful information about the graphics block. This can be of immense help in situations where one searches for information from a large database of document images. In this information rich modern era, one often comes across such situations where the search results are needed at the finger tips. There are two basic issues associated with this : (a) to represent the bulky raw-data in the compact and interactive form (b) to retrieve relevant information from the database.