Image Covert Communication With Block Regulation

Image covert communication camouflages or conceals sensitive information in regular digital images during transmission to avoid detection or interception. It is widely used in military, intelligence, and law enforcement agencies. Data hiding is a feasible solution for covert communication, which embeds confidential information in cover media while preserving its visual appearance. In this letter, we propose an image reversible data hiding (RDH) scheme based on block regulation, which embeds secret data using pixel permutation. Traditional permutation-based data embedding methods usually suffer from error restoration of the cover image. To solve this problem, we propose a regulation operation to pre-process the image blocks, and thus most of the image blocks are converted into regular blocks. The regulated image blocks can be exploited to embed secret data without restoration error. In addition, we propose an adaptive strategy to generate permutation table dynamically, which further enhances the security level. Experimental results indicate that the proposed scheme provides a good embedding capacity and preserves a high level of image visual quality.