A NOVEL ONLINE EXAMINATION MANAGEMENT FRAMEWORK WITH DOCUMENT WATERMARKING

Online examination management is become a tedious task nowadays due to the coronavirus disease pandemic. In this article, we propose a new online examination management framework which uses document watermarking scheme. For the last few years, visible watermarking schemes are widely used for copyright protection and image authentication. The visible watermarking schemes usually alter the contents of the image to show the watermarks. In general, the visible watermarks will stay in the image permanently. In this paper, we propose a new semi-transparent watermarking scheme which will help to embed a watermark in the image (semi-transparent), and later the authorized person can remove the watermark to recover the original image for further usage. The key idea behind the proposed scheme is that the loss of information (changes in pixel values) during watermarking will be recorded and that information will be embedded in the remaining portion of the same image by using a reversible data hiding scheme. One of the main applications in the current scenario is for embedding unique student information (such as register number) in the scanned answer sheet images while conducting the examinations in distance mode. The receivers (evaluators) can see the watermark and later, they can remove the watermark before evaluating the answer scripts. The experimental study is conducted on sample scanned written document images and the results show that the proposed scheme can be used for practical applications.