Interpolation data hiding schemes based on center folding strategy and well-turned embedded positions

Abstract

In the realm of steganography, payload and Peak Signal-to-Noise Ratio (PSNR) are pivotal metrics for evaluating the efficacy of data hiding techniques. While addressing security concerns, researchers have been striving to optimize one or both assessment indicators. As indicated by Lu et al. (2020), a reversible data hiding method can achieve high PSNR and payload capacity. This method employs a multi-layer center folding strategy for message concealment in interpolated images. In our study, the secret message is transformed into a code pair consisting of an index and code, utilizing Lu's scheme. Our proposed approach reorganizes these indexes and applies two distinct strategies, termed EnMCFS-8 and EnMCFS-9, aiming to refine data hiding quality through strategic embeddable position arrangements. In each 4 × 4 block of the cover image, EnMCFS-8 focuses on embedding eight indexes at the four locations, minimizing image distortion. Conversely, EnMCFS-9 distributes nine indexes across three diagonal locations to augment the hiding capacity. Each method serves specific objectives effectively. The experimental outcomes demonstrate the enhancements in hiding performance our proposed methods when compared to existing techniques.