Anti-Forensics of Camera Identification and the Triangle Test by Improved Fingerprint-Copy Attack

• Main Authors: Li, Haodong, Luo, Weiqi, Rao, Quanquan, Huang, Jiwu
• Format: Journal Article
• Language: English
• Published: 24.07.2017
• Subjects: Computer Science - Multimedia
• DOI: 10.48550/arxiv.1707.07795

The fingerprint-copy attack aims to confuse camera identification based on sensor pattern noise. However, the triangle test shows that the forged images undergone fingerprint-copy attack would share a non-PRNU (Photo-response nonuniformity) component with every stolen image, and thus can detect fingerprint-copy attack. In this paper, we propose an improved fingerprint-copy attack scheme. Our main idea is to superimpose the estimated fingerprint into the target image dispersedly, via employing a block-wise method and using the stolen images randomly and partly. We also develop a practical method to determine the strength of the superimposed fingerprint based on objective image quality. In such a way, the impact of non-PRNU component on the triangle test is reduced, and our improved fingerprint-copy attack is difficultly detected. The experiments evaluated on 2,900 images from 4 cameras show that our scheme can effectively fool camera identification, and significantly degrade the performance of the triangle test simultaneously.