Nowadays, digital images are widespread and also easily tampered, which promotes the development of digital image forensics techniques rapidly. A series of forensics techniques have been developed to reveal sophisticated forgeries and intentional manipulations. However, few methods consider multiple operations together and provide a complete description of the processing history of a digital image. Multiple operations detection is a challenging problem in the research field of forensics.
In this paper, for tracing such processing history, we propose a two-step approach to estimate the topology and order of the operation chain applied to a digital image. We propose an operation chain topology fingerprint (OCTF) to identify the operation chain which an image has undergone. The operation chain order fingerprint (OCOF) is proposed to discriminate the order of the operations. Simulation results verify the effectiveness of our proposed scheme in two sequential operations scenarios.