A novel VQ-based reversible data hiding scheme by using hybrid encoding strategies

Abstract

Reversible data hiding is a special algorithm that not only guarantees the confidential data will be extracted accurately but also allows the original cover image to be reconstructed without distortion after the confidential data are completely extracted. This paper proposes a new index compression and reversible data hiding scheme based on side-match vector quantization (SMVQ) and search order coding (SOC). In this proposed scheme, the confidential data are embedded into the transformed index table of a cover image. During the extracting phase, simple steps are employed to extract the confidential data and reconstruct the original cover image. The experimental results show that with a codebook size of 256, the average compression rate of the proposed scheme is 0.325bpp, which is superior to that of the methods proposed by Chen and Huang (0.426bpp) and Chang et al. (0.429bpp). Additionally, the embedding and extracting times of our scheme are 5.491s and 0.352s, respectively, demonstrating that the execution time of the proposed scheme is much faster than that of the methods of Chen and Huang and Chang et al. Moreover, our scheme achieves better performance than other selected reversible data hiding schemes with respect to the data embedding and data compression rates.