Dewarping Document Image Techniques: Survey and Comparative Study

In recent years, everyone has his/her own handheld digital devices such as PDAs and camera phones which are used to capture any documents, for example, posters, magazine and books. This is the simplest way to disseminating and collecting information. Unfortunately, the snapshot of this document in an uncontrolled environment has been suffering from different perspectives and geometric distortions, especially when a picture is taken from rolled document, page of thick book, multi-folded documents and crumpled pages. In such cases, the most common distortion appeared is warping text lines. In this paper, we present a survey and a comparative study of document image dewarping techniques which aim to solve the curled lines and geometric distortion problems. We introduce a new classification of the available dewarping document image techniques and investigate their available datasets. Finally, we present the evaluation metric to test these techniques.