Conventional image forgery relies heavily on various digital image processing techniques, which will inevitably introduce artifacts and inconsistency. For the goal of raising suspicion over the integrity of a genuine picture P, we proposed an ambiguity attack not employing any digital image processing techniques. It works by deliberately producing a second picture Pamb containing a target ROI(Region-of-Interest) that highly resembles the ROI in P. Except for the target ROI, the rest of the contents might be dramatically different between P and Pamb, so that Pamb tells a rather different story from P. Since Pamb is not involved with any forgery in digital domain, Pamb shall pass generic digital image forensic tests. Furthermore, several measures can be taken to make the ROI in Pamb looks more 'original' than its counterpart in P, which induces people to believe Pamb is genuine and P is no more than a forgery derived from Pamb instead. The ambiguity created between P and Pamb is hard to resolve due to three reasons. Firstly, no digital forensic tool shall identify any artifacts or inconsistency in Pamb; secondly, the fact of being able to pass all digital forensic tests still does not assure P is genuine; lastly, determine the chronological order of P and Pamb is very hard for general cases.
Jun Yu, Enping Li, Scott Craver, "Ambiguity Attack on the Integrity of a Genuine Picture by Producing Another Picture Immune to Generic Digital Forensic Test" in Proc. IS&T Int’l. Symp. on Electronic Imaging: Media Watermarking, Security, and Forensics, 2016, https://doi.org/10.2352/ISSN.2470-1173.2016.8.MWSF-066