Enhancing Adversarial Embedding based Image Steganography via Clustering Modification Directions

Abstract

Image steganography is a technique used to conceal secret information within cover images without being detected. However, the advent of convolutional neural networks (CNNs) has threatened the security of image steganography. Due to the inherent properties of adversarial examples, adding perturbations to stego images can mislead the CNN-based image steganalysis, but it also easily leads to some errors when extracting secret information. Recently, some adversarial embedding methods have been proposed for improving image steganography security. In this work, we aim at furthering enhance the security of adversarial embedding-based image steganography by exploiting the strong correlation between adjacent pixels. Specifically, we divide the cover image into four non-overlapping parts for four-stage information embedding. During the adversarial embedding process, we cluster the modification directions of adjacent pixels and select only those with relatively larger amplitudes of gradients and smaller embedding costs to update their original embedding costs. Experimental results demonstrate that our proposed method can effectively fool targeted steganalyzers and outperform state-of-the-art techniques under different scenarios.