🤖 AI Summary
Existing machine learning–based steganographic distortion design methods neglect the inherent stochasticity (i.e., natural fluctuations) in generative model outputs, compromising steganographic security. To address the security vulnerability of generative images as steganographic carriers, this paper proposes an end-to-end distortion learning framework grounded in fluctuation modeling. Specifically, we first formulate the intrinsic output fluctuations of generative models as a hard constraint on steganographic distortion; second, we construct a fluctuation image set to guide the distortion distribution; and third, we introduce a novel GAN-based adversarial training strategy to align the feature representations of stego images with those of their source-matched fluctuation images. This approach transcends conventional handcrafted or generic deep distortion models. Evaluated on three state-of-the-art steganalyzers, it achieves an average detection error rate improvement of 3.30%, significantly outperforming existing GAN-based methods.
📝 Abstract
Minimum distortion steganography is currently the mainstream method for modification-based steganography. A key issue in this method is how to define steganographic distortion. With the rapid development of deep learning technology, the definition of distortion has evolved from manual design to deep learning design. Concurrently, rapid advancements in image generation have made generated images viable as cover media. However, existing distortion design methods based on machine learning do not fully leverage the advantages of generated cover media, resulting in suboptimal security performance. To address this issue, we propose GIFDL (Generated Image Fluctuation Distortion Learning), a steganographic distortion learning method based on the fluctuations in generated images. Inspired by the idea of natural steganography, we take a series of highly similar fluctuation images as the input to the steganographic distortion generator and introduce a new GAN training strategy to disguise stego images as fluctuation images. Experimental results demonstrate that GIFDL, compared with state-of-the-art GAN-based distortion learning methods, exhibits superior resistance to steganalysis, increasing the detection error rates by an average of 3.30% across three steganalyzers.