Reversible data hiding based on image histogram modification

Reversible data hiding has drawn lots of interest recently. Being reversible, the decoder not only can extract hidden data from the embedded image but also can completely recover the original image without distortion. Two reversible data hiding methods based on histogram modification are proposed in this paper. The proposed methods differ from other histogram modification based schemes. The peak point in the histogram keeps unchanged for retrieving hidden data without additional side information. Thus, secret data will be embedded in the peak's neighbouring pixels. Additionally, the original image is divided into blocks to increase embedding capacity. Experimental results show that the authors' methods can achieve a high image quality above 48 dB and have high embedding capacity.