Design of an Edge Detection Based Image Steganography with High Embedding Capacity

Abstract

In this paper, the authors have proposed an image steganography method for improving the embedding capacity of the gray-scale cover image. In general, the embedding of the secret message into the sharp areas i.e. edge region rather than in the smooth areas i.e. non edge region of the cover image attains relatively better quality stego-image. So in the proposed work, we have also exploited the presence of edges in the cover image to embed a large amount of secret message into the cover image. The proposed method carried out into two phases: in the first phase the cover image is classified into edge region and non-edge region. Subsequently in the second phase, the binary secret message bits are embedded by replacing some least significant bits (LSBs) of each pixel. In the proposed work, x LSBs replacement are preferred for the pixels belongs to edge region and y LSBs replacement are considered for non-edge region pixels where x>y. The proposed method increases the embedding capacity of the cover image compare to some existing standard steganographic methods. The scheme has been tested on several standard gray-scale test images and the obtained simulation results depict the feasibility of the proposed scheme.