Securing Transcation Image Files Using Digital Watermarking

Abstract

This research paper examines the problem of guaranteeing electronic document integrity. Digital watermarking will be presented as a potential means of accomplishing this goal. The paper proposes an electronic exam exchange program as a frame of reference for the research conducted. In the case of an exam document exchange system, one must accommodate the transfer of both text and handwritten information within these documents. Exams are typically in ASCII text format and printed onto paper so that students can handwrite answers in the appropriate location. The system must be constructed in a way so that security measures are not defeated when the document is transformed from paper to electronic format. The research paper will present a potential method for dealing with this issue. During a document’s existence in paper form, its quality can be degraded significantly. Paper can be folded, soiled or marked. During the rescanning of this document, the document can be degraded to the point where its security markings can become unusable. After scanning, common operations on an image file such as cropping, rotation and compression can also negatively impact its security marks. This paper proposes a watermarking technique that uses optical character recognition to verify the integrity of security artifacts embedded in a digital file. The experiment outlined in the paper was conducted using a prototype modelling the technique described. The results of this experiment are used to evaluate the technique’s utility.