Feature string-based intelligent information retrieval from Tamil document images

Abstract

Information Retrieval (IR) in document images has become a growing and challenging problem due to its rising popularity. This paper proposes a simple and effective method to extract the text and perform intelligent IR from Tamil Document Images without Optical Character Recognition (OCR). This methodology generates a feature string for every word image by extracting its features. This relies on their basic characteristics or shapes of letters instead of recognising the letters like OCR. The strength of this technique lies in extracting the text based on their basic features such as lines and black and white disposition rates in characters which is almost same for the characters across various font sizes and font faces. As an offline process, document images are preprocessed and text extraction process extracts the features from the word images based on their shapes and they are stored in temporary files. During online retrieval, textual keyword is obtained from the user and its primitive string is framed. Based on the primitive string, IR is performed and the resultant images are provided to the user. This technique could be easily adopted in large digital libraries for IR.