A multi-layer mesh synchronized reversible data hiding algorithm on the 3D model

Reversible data hiding (RDH) techniques can extract the complete secret information and recover the original 3D models. However, modifying vertices in the spatial domain to embed data may lead to inaccurate information extraction, and this phenomenon is known as mesh asynchrony. To mitigate this risk, this paper proposes a multi-layer mesh synchronous RDH (MS-RDH) in spatial domain, which solves the potential mesh asynchrony problem in mesh synchronization using minimum distortion analysis, and embeds data into the redundant regions of the model based on smoothness sorting. In addition, we have designed a logical mapping strategy and a multilevel bimodal mapping rule to embed data to improve the overall embedding ability of the model. Experimental results show that the MS-RDH has achieved a signal-to-noise ratio (SNR) above 92.15 dB in most test mesh models, while the payload is close to 3 bit per vertex (bpv) in each layer. Our algorithm not only avoids mesh asynchrony problems, but also makes geometric distortion of the model difficult to detect.