Reversible Multi-Level Watermarking Scheme for Color Images

Reversible data hiding is to embed data into digital multimedia, while the original multimedia and embedded data can be restored from the watermarked one without any loss. In this paper, we propose a novel Reversible Multi-Level Watermarking (RMLW) scheme for color images with grayscale invariance. Being different from the traditional reversible data hiding methods, we adapt the gray scale-invariant reversible watermarking method which keeps the grayscale of image unchanged as the information is embedded. In the RMLW, one feature region of high robustness is extracted and into which the watermarks are then embedded for multiple times. Lots of experiments have been conducted and the results show that the proposed scheme can extend the capacity efficiently while keep the characteristic of grayscale invariance.