Study of Difference-Expansion Embedding Schemes

Difference expansion (DE) is one of the famous schemes in the field of reversible data hiding. With the high efficiency and simplicity, DE also has received more attention over the years. DE has a good information capacity, but due to its major location map, the pure payload is rather low. Therefore many scholars did relevant improvements which let n pixels as a unit instead of the original two pixels as a unit and can adaptively adjust the number of embedding secret information according to the smoothness degree of the block, which achieves the result of improving the information payload or the image quality. In this paper, the study of DE-based reversible data hiding schemes is comprehensively discussed. The performance of DE-based schemes is evaluated and compared in terms of embedding capacity and stego-image quality.