A GAN-based anti-forensics method by modifying the quantization table in JPEG header file

It is crucial to detect double JPEG compression images in digital image forensics. When detecting recompressed images, most detection methods assume that the quantization table in the JPEG header is safe. The method fails once the quantization table in the header file is tampered with. Inspired by this phenomenon, this paper proposes a double JPEG compression anti-detection method based on the generative adversarial network (GAN) by modifying the quantization table of JPEG header files. The proposed method draws on the structure of GAN to modify the quantization table by gradient descent. Also, our proposed method introduces adversarial loss to determine the direction of the modification so that the modified quantization table can be used for cheat detection methods. The proposed method achieves the aim of anti-detection and only needs to replace the original quantization table after the net training. Experiments show that the proposed method has a high anti-detection rate and generates images with high visual quality.