Dual Transform Technique for Robust Steganography

Abstract

Steganography enables to have a secret communication in modern information technology using public channel. In this paper, we propose Dual Transform Technique for Robust Steganography (DTTRS). The cover image is segmented into blocks of 4*4 each and Discrete Wavelet Transform (DWT) is applied on each block. In the resulting DWT coefficients, blocks of vertical band of 2*2 each are considered and Integer Wavelet Transform (IWT) is applied to get blocks of 1*1 each. The IWT is applied on vertical band of DWT of payload to generate coefficients of payload and are embedded into IWT coefficients of cover image using least significant bit replacement method. On applying IIWT and IDWT, stego image is derived. The concept of error detecting and correcting coding technique is employed to ensure more reliable communication. It is observed that the proposed algorithm has excellent PSNR, provides high level security and more robust compared to individual transform techniques.