Variational Cover Modification Steganography

Current approaches to learning-based image steganography are, at best, imperceptible, but their security is vulnerable to state-of-the-art detector networks. Variational cover modification steganography tackles this problem by training a generator network that can predict the parameters of the distribution of the least detectable stego-noise for a given cover image. It uses syndrome coding to embed the message within the distribution constraint and retrieve it exactly when a secret key is provided. Adversarial learning ensures that the generator evolves against a continuously refined detector. Experiments demonstrate significant security improvements, and several ablations support the generator architecture and the training protocol.