An efficient multiple-bit reversible data hiding scheme without shifting

摘要

For the past few years, the data-hiding schemes are growing rapidly. Generally, data hiding performs well on common images but it does not provide satisfying results on distortion sensitive images such as medical, military, or forensic images. This is because embedding data into an image can cause permanent distortion after extraction (irreversible). As a solution, a certain scheme is required for the process of embedding data into an image, such as reversible data hiding (RDH). One well-known RDH scheme is difference expansion (DE), which is simple, easy to implement. Due to the local correlation between two neighboring pixels, conventional DE-based schemes utilize some empirical criteria to embed one bit into one of the pixels, which does not fully consider the correlations of pixels in neighborhood. In this study, an efficient multiple-bit reversible data hiding scheme without shifting (EMRDH), is proposed, focusing on increasing capacity and visual quality of data hiding. Firstly, a pixel is taken as an embeddable pixel (EP)or a non-embeddable pixel (NEP) according to its relations with the left and right neighbors, and then the EP is substituted with a new pixel consisting of flag-bits, offset-bits and embedding bits, without the difference histogram and expansion processes. With the flag-bits and embedding bits, the embedded data can be extracted without any error while the EP or NEP can be losslessly recovered with the flag-bits, offset-bits. Experimental results show that the proposed scheme has higher capacity, better visual quality and lower computational complexity compared with previous works.