Research On Covert Communication Based On Audio Information Hiding Technology

Information hiding is a novel technique in the field of information security in this years, and it is significant to covert communication. Comparing with copyright protection reasearch with information hiding technology, it is an open issue for audio covert communication research. It's necessary to consider the audio signal's attacks, such as desynchronic attack, Time Scale Modification attack, D/A and A/D convertion attacks.Three kinds of audio information hiding algorithms are designed to resist on much more attacks in audio covert communication. Experimental results show that these algorithms are good transparent and robust.Firstly, the principle and current research status of audio information hiding is detail analyzed and the knowledge of audio information hiding technology is introuduced.Secondly, an audio information hiding algorithm based on energy relationship in wavelet domain is designed for resisting synchronic attack. A synchronic signal and chaotic sequence are applied in the algorithm in order to improve algorithm's robustness and security.Thirdly, audio information hiding algorithm robust to Time-Scale Modification attack is still an open issue. Noted that the robustness of audio histogram and Centroid to the time-scale modification verfied in large of extensive tests, then, a watermaking algorithm is proposed. The experimental results show that the algorithm is very robust to resample TSM and a veriety of common attacks.Finally, considering covert communication's characteristic, an improved LSB algorithm is designed and is implemented by C# 2003. A covert commnication system with audio information hiding based on digital tranmission is designed and makes a foundation for research of audio information hiding algorithm.