A High Payload Steganography Method based on Pixel Value Differencing

Abstract

Steganography, a way for covert data communication, aims to send some secret messages via embedding them into digital image imperceptibly. This paper proposes a new adaptive steganography method based on the well-known pixel value differencing (PVD) technique. The method tries to enhance the payload of the hidden secret data and to improve the security of the stego-color image. To this end, the image is partitioned into 2-pixel blocks in a nonoverlapping fashion and scanned in a raster-scan order. The hiding payload of the original PVD method is investigated by considering two-directional edges: horizontal and diagonal directions with the color image. These directions are utilized in designing the proposed adaptive horizontal and vertical pixel value differencing (A-HDPVD) method. For improving the security, different numbers of secret bits are used for embedding adaptively in the two directions of each color pixel lie in the edges using the original PVD method. The experimental results show that the proposed method provides better visual quality and a high payload of the stego-image. Moreover, the proposed method is more robust against RS statistical steganalysis attacks.