A novel approach for data hiding based on combined application of discrete cosine transform and coupled chaotic map

In the recent years chaotic map and Discrete Cosine transform (DCT) have surfaced to become an important field in data hiding methods. In this proposed work, a randomly high embedding chaotic value differencing method (RCVD) based on combined application of DCT and Chaotic map is proposed. DCT has energy compaction property which removes the rounding error problems in the embedding and extraction process. Whereas, chaotic maps have significant properties of sensitivity to initial and control parameters, which help to provide security to the proposed algorithm. The embedding of secret data is done by hybrid method namely randomly chaotic value differencing (RCVD). RCVD maintains the human vision system (HVS) by embedding more data in smooth area than in edge area. The experimental results are calculated in terms of Peak Signal to Noise Ratio (PSNR) and embedding capacity. The security of the proposed method is examined by the key space, key sensitivity parameter and histogram analysis. Additionally universal image quality index (Q) and entropy are also calculated for the proposed method. The evaluated results show that the proposed method outperforms the existing steganography techniques in terms of embedding capacity and PSNR.