A High Capacity Embedding Scheme Based on Graph Theory Randomness and Bit Difference for Covert Communication

Abstract

Stenographic techniques are hiding methods that are used in secret communications to transmit secret data inside a carrier media. In this paper, a new image steganography technique based on graph theory and bit difference is proposed. Secret image is divided into blocks and randomized based on graph theory. The cover image is divided into four blocks and each secret image pixel is grouped into four two-bit groups and concealed inside the cover media. The embedding algorithm is based on a modified version of bit difference which is considered more secure. The proposed method is applied in the spatial and transform domain using Integer wavelet transform (IWT) since, IWT is less distortional in retrieving images compared to the discrete wavelet transform (DWT). Performance analysis of the proposed scheme is tested using peak signal to noise ratio (PSNR) and embedding capacity using various cover image formats such as (TIFF, PNG, BMP, and JPEG). Results show that the proposed scheme is superior over several embedding schemes in terms of capacity and visual symmetry.