Improving Security of Pixel Value Differencing Steganographic Method

Pixel value differencing (PVD) is a steganographic method which embeds secret data in images based on spatial information. PVD has relatively high capacity but its effectiveness has been questioned by variety of steganalysis attacks. These attacks use the difference histogram quantization to reveal existence of secret data in a stego image. In this paper, we propose some modifications to PVD method to make it more robust to histogram quantization. Hence, at the expense of slight reduction in the capacity of the original algorithm, PVD's stability against histogram quantization attacks is significantly improved.