Watermarking schemes for digital images: Robustness overview

Digital watermarking is an important scientific direction located at the intersection of cybersecurity and multimedia processing. Digital watermarking is used for digital objects copyright protection and protection against forgery. The importance of those tasks is highlighted by the ongoing COVID-19 pandemic that lasts for more than a year and forced multiple industries to transit to online. The main digital watermarking application include active attackers whose goal is to destroy or damage watermarks. Thus, digital watermarking schemes must be robust to attacks. Despite of the large number of existing digital watermarking schemes, a comprehensive analysis of their robustness towards various attacks does not exist. Our study aims to fill this gap. In this article, latest years findings in digital watermarking are systematized. First of all, we review the most prominent distinctive features of watermarking schemes, attack types, and performance measures to facilitate navigation in digital image watermarking. Then, we introduce classification of digital watermarking schemes by their robustness towards various classes of attacks. We believe this classification could be useful for researchers who aim to choose a digital watermarking scheme for their application with a known set of attacks. Finally, we highlight the most promising solutions that further development could lead to schemes with better robustness compared to existing schemes.