A novel steganographic method for gray-level images with four-pixel differencing and LSB substitution

In this paper we propose a novel steganographic method for hiding information within the spatial domain of the gray scale image. The proposed approach works by dividing the cover into blocks of equal sizes and then embeds the message in the edge of the block depending on the number of ones in left four bits of the pixel. Our experimental results have shown that the proposed method not only has an acceptable image quality but also provides a large embedding capacity. Our results are compared with the PVD method [7], and the values obtained are better than the PVD method (see Table 2).