一种基于基音预测的信息隐藏算法

针对低速率语音编码问题，提出一种基于基音预测的信息隐藏算法。在基音预测编码过程中，采用控制基音闭环搜索的自适应码本搜索范围方法，实现秘密信息的嵌入，在进行语音压缩的同时完成信息隐藏。实验结果证明，该算法具有良好的隐蔽性，且计算复杂度较低。在编码标准G.729a中，秘密比特信息嵌入速率统计平均最高可达374.636 bit/s，PESQ恶化改变率在10.4%以内，检测正确率在66%左右。

An Information Hiding Algorithm Based on Pitch Prediction

Information hiding algorithm based on pitch prediction for low bit-rate speech coding is presented. In the pitch prediction coding process, the searching range of adaptive codebook in the closed-loop pitch search is used to realize the secret information embedding. Information hiding and speech coding are synchronously implemented. The algorithm not only has better steganography performance, but also has lower computational complexity. In G.729a, the statistical average embedding bit-rate of secret information is up to 374.636 bit/s, the deterioration of Perceptual Evaluation of Speech Quality(PESQ) is less than 10.4% and testing accuracy is less than 66%.