Research And Implementation Of Audio Steganography Based On3G Speech Encoding

How to ensure security of information has become an increasingly cirtical issue in thecomplex network. Steganography is one of the important means to safeguard informationsecurity, it does not allow anyone other than the intended recipient to know the delivery eventof information and content. Audio steganography is the way which audio is treated as covermedia, and it is getting more and more attention of researchers. This paper mainly studiessteganography methods using speech encoding parameters of3G networks.(1) Proposed an improved steganography method based on immittance spectralfrequency index parameter. Five codebooks are required in the second stage quantizationprocess of ISF parameter in non6.60kbit/s mode, which can be used to hide information. Theembedding capacity of existing method is very limited. Proposed algorithm in this paperfirstly partitioning verctors in codebook according to the Euclidean distance. Then finish thesteganography process by replacing standard ISF indexs with other ISF indexs correspondingcode vectors in the same sub-codebook according to secret message. Simulation experiment isperfomed on individual codebook firstly, then hiding data with five codebooks at the sametime. Simulation results show that2.2to3times embedding capacity than the original methodhas been obtained with little effect on voice quality.(2) Proposed a steganography method based on algebraic codebook index parameter.Index of algebraic codebook is represented by the coded positions and symbols of non-zeropulses located in each subframe. In this paper, the critical issue of pulse positions become outof order has been resolved. Then we can hide secret data by choosing the position of last pulsein each track. This paper also proposed a steganography solution which use the pseudorandom number to select different tracks for each sub-frame thereby further increasingsteganography security. Experiments show that, while protecting the voice quality, theproposed method has obtained embedding data rate of400bps to3200bps with goodconcealment.