Moiré pattern generation-based image steganography

Abstract

Generative steganography has developed recently due to its high resistance against steganalysis detection. It usually synthesizes stego images directly from secret information. In contrast to this manner, we propose a generative steganographic scheme by synthesizing Moiré patterns in this paper. Moiré patterns are widely observed in captured photos. They present various shapes, colors, and frequency ranges, which are expected to help carry secret information robustly and securely. The scheme synthesizes Moiré patterns via a Moiré pattern generator. Then a secret message is encoded in these patterns by a parallel encoder. The Moiré pattern generator employs a multi-branch structure to generate sub Moiré patterns at distinct frequencies. A discriminator is further imposed to ensure the realness of synthesized Moiré patterns. The parallel encoder spreads secret information over Moiré patterns in both frequency and spatial domain. A decoder and a steganalyzer are also included to ensure the robustness and undetectability of the information hiding. Furthermore, a two-stage training strategy is designed to accomplish both Moiré pattern generation and information hiding tasks. Experimental results demonstrate that the proposed scheme presents high undetectability against existing steganalytic tools, meanwhile, it can resist common image attacks such as AWGN and JPEG compression.