A high capacity data hiding scheme based on re-adjusted GEMD

Steganography is a useful technology to protect secret data traveling through the Internet. Recently, Kuo and Wang proposed a useful data hiding scheme based on GEMD(Generalized Exploiting Modification Direction). They claim that the embedding capacity of their scheme is more than 1 bpp(bits per pixel) and keeps good stego-image quality. In addition, the GEMD scheme can prevent RS detection. However, the embedding capacity of GEMD decreases when pixel numbers in the group becomes large. To alleviate this shortcoming, we will propose a data hiding scheme which can embed extra secret data after the GEMD embedding procedure. The major contribution of the proposed scheme is the embedding capacity always maintains 2 bpp which is independent of the pixel numbers in the group. Finally, according to our experiments, our proposed scheme maintains good image quality and also prevents RS detection.