A security enhanced robust audio steganography algorithm for image hiding using sample comparison in discrete wavelet transform domain and RSA encryption

Steganography is the technique of hiding any secret information like text, image or video behind a cover file. Audio steganography is one of the widespread data hiding techniques that embeds secret data in audio signals. The secret data is hidden in a way that unauthorized people are not aware of the existence of the embedded data and without changing the quality of the audio signal (cover audio). Data hiding in audio signals has various applications such as protection of copyrighted audio signals, secret communication, hiding data that may influence the security and safety of governments and personnel. This paper proposes an efficient steganography scheme based on sample comparison in Discrete Wavelet Transform (DWT) domainwhere the cover audio is decomposed into several multi sub-bands, and then selected coefficients of details are changed by a threshold value depending on the embedding cipher image bit. This approach employs an original image component to perform RSA encryption on it, then cipher bits are embedded in the details components of the audio signal according to a predetermined threshold value. The performance of the algorithm has been estimated extensively against attacks, and simulation results are presented to prove the robustness of the proposed algorithm.