Undetectable image tampering through JPEG compression anti-forensics

Recently, a number of digital image forensic techniques have been developed which are capable of identifying an image´s origin, tracing its processing history, and detecting image forgeries. Though these techniques are capable of identifying standard image manipulations, they do not address the possibility that anti-forensic operations may be designed and used to hide evidence of image tampering. In this paper, we propose an anti-forensic operation capable of removing blocking artifacts from a previously JPEG compressed image. Furthermore, we show that by using this operation along with another anti-forensic operation which we recently proposed, we are able to fool forensic methods designed to detect evidence of JPEG compression in decoded images, determine an image´s origin, detect double JPEG compression, and identify cut-and-paste image forgeries.