A High Visual Quality Embedding Method in Edges Based on Pixel Pair Difference

In this paper, we proposed a new data hiding method based on diamond encoding (DE) and pixel pair difference (PPD). DE proposes a pixel-wise algorithm which flexibly embeds different base digits to maximize payload and image visual quality. During DE embedding, digits embed in sequence without separately consider smooth areas and complex areas. We propose a method based on human visual system in that human eyes are more sensitive to the change of smooth areas where pixel pairs possess less difference. Embedding secret message in complex areas insignificantly affects visual quality of the image, correspondingly makes the stego image less detectable. The proposed method uses PPD to adaptively embed secret message in complex areas and thus improves DE performance. Experimental results illustrate that our algorithm has the same distortion with DE but provides a better visual quality of stego image.