Hybrid DWT- DCT image steganography for encrypted secret image

Abstract

Steganography is the science of hiding secret information in any cover medium like image or video, for the purpose of secure transmission. However, steganography ensures protection of data by hiding it in a cover object. Moreover, cryptography along with steganography, ensures security in depth. Cryptography is the technique of encrypting the original information using a key. Challenging aspects in Image steganography are to increase the payload capacity of secret information and robustness against visual attacks and statistical attacks. DWT and DCT techniques when applied simultaneously provide advantages of both the techniques. The proposed technique of image steganography provides higher robustness against statistical attacks, higher imperceptibility. This technique is more secure as the encrypted secret image is hidden in two cover images, with prior application of DWT and DCT on both cover images. The simulation results illustrate the high embedding capacity and reasonable PSNR values.