Research And Realization Of Information Hiding For Digital Audio

For improving the limits on the applications of data encrypting,information hiding technique has received a great deal of attention in theacademic field of international and internal information security since thenineties. In the area of information hiding utilizing digital audio signalespecially the voice data for information hiding is a new field, it is rapidlydeveloped in recent years under the excitation of application demand, and itis a practical technique close in combination with applications. With thedevelopment of computer and network, its value will be greater, so it isnecessary to do research on the technique for information hiding in audiosignal.This paper firstly introduces the general principal of informationhiding for digital audio, as well as cepstrum analysis, wavelet transformand GSM audio coding. And then the paper researches three representativealgorithms. For each algorithm, we research it in the four aspects: basic idea, material algorithm, emulational analysis and discussion.The algorithm based on cepstrum utilizes that the mean of coefficientsof cepstrum transform does not change greatly, it modifies the coefficients.The test shows that it has good imperceptibility but poor embeddingcapacity.The algorithm based on wavelet utilizes the multi-scale analysis ofwavelet transform; it modifies the coefficients of wavelet transform. Thetest shows that it has good imperceptibility as well as embedding capacity.The algorithm based on GSM coding utilizes the difference of outputbits, it processes the secret message using a matrix, it can embed severalbits but only changes one bit in the cover data. The test shows that it hasgood imperceptibility and embedding capacity.At the end of the thesis, the prospect of Information Hiding for DigitalAudio is discussed, as well as potential ways for further research.