Speech Hiding Algorithm Based on Speech Parameter Model
Liang Chen · Chinese Journal of Computers · 2003
Based on speech parameter model, a novel approach to embed secret speech into open speech is proposed in this paper. First, secret speech is coded into binary parameter bits with Mix-Excitation Linear Prediction (MELP) algorithm, and the bits are arranged to form hiding information sequence. Then open speech is divided into several frames for information embedding. On every frame, according to crosscorrelation-based pitch detection method, the instantaneous pitch is utilized to determine the current embedding position in frequency domain of open speech. Finally, information hiding procedure is completed by modifying relevant frequency coefficients, which is controlled with current information bit. At the receiver, based on the same pitch detection method, the embedding position is found and the hiding bit is recovered sequentially. After MELP decoding, the secret speech waveform can be recovered entirely. The experimental results show that the average SNR of middle speech is close to 60dB, and the watermarking is strongly robust to many attacks such as compression, filter and so on. This algorithm provides a new approach for the research on information security and digital watermarking.