Enhancement Methods of Image Quality in Screen Mark Attack

Abstract

In this paper, we propose an Enhancement Screen Mark System (ESMS) that improves image quality better than the current Screen Mark System (SMS). Screen mark attack is similar in copy attack method and creates a good quality image that contains a watermark of the attacker. A copy attack does not destroy a watermark that is embedded in target image, and does not impair its detection. Attacker inserts his watermark into the target image by a method that copies his watermark to the target image. Attacker does not need to know any information about the watermark system of target image; it creates new challenges, especially when watermarks are used for copyright protection and identification. The proposed system uses the Gaussian Blur Filter (GBF) to remove a watermark in the target image and create a screen mark. It selects the most efficient screen mark and includes Image Quality Enhancement Module (IQEM). As a result, we get an improved result of about 0.8db to 2.3db on test images.