Abstract
Digital image acquisition is now a simple task and information in the form of digital images is drastically increasing on social media, which has both positive and negative impacts on a society in many different ways. Advanced user-friendly tools have made it easy to manipulate image content in order to gain illegal advantage or to make false propaganda, and digital images and videos are not acceptable in courts of law as evidence without reliable forensic analysis. A lot of research has been done in order to address this problem and many techniques exist that detect and localize copy-move and splicing forgeries. However, it is very important to know whether these methods are robust, properly modelling the structural changes that have occurred in images due to copy-move and/or splicing forgeries, and can reliably classify a digital image as a genuine or modified image. In this paper, we present an extensive literature review of the state-of-the-art techniques on copy-move and splicing forgeries, highlighting their limitations, and we provide future research directions.