中文摘要：

语音信息隐藏的关键问题之一是信号的实时处理，回声隐藏具有高透明性和鲁棒性，但是其解隐藏算法复杂耗时。提出一种快速算法，对N点序列，峰值运算量至多是普通算法的1／N，整体运算量约是普通算法的30％，能够满足实时处理的要求。

英文摘要：

One of the key challenge of audio information hiding is real-time signal processing. Although echo hiding has dominance in transparence and robustness, the complexity of extracting information make it impossible to meet real-time requirements. Put forward a fast algorithm that settle the problem. In the case of N-samples sequence, the peak value of the fast algorithm is 1/N of that of the old one, and total instructions of the new one is about 30% of that of the old.