中文摘要：

提出一种采用HOOK机制实现以即时通信语音流为隐藏载体的隐写模型，在通信软件的发送端挂接两个“钩子”，采集即时通信语音流作为载体进行实时机密信息嵌入与提取，实现交互式的隐蔽通信过程。选择目前普遍使用的Google talk软件作为研究对象，重点研究Gtalk的iSAC语音编码的隐写方法，建立一种基于LPC参数量化的隐写算法，实现iSAC语音编码下的隐写方法。实验结果表明，该隐写模型适用于目前的即时通信软件的隐蔽通信，拓展了基于VoIP的信息隐写的应用范围；该隐写算法具有良好的隐写容量和隐写速率。

英文摘要：

A steganographic model using HOOK mechanism to achieve instant communication speech stream for hiding carrier was presented.Two“HOOK”were hung in the sender,and the speech stream was collected as hiding carrier for real-time embedding and extracting,thus the interactive covert communication was realized.The Google talk software currently used was selected as the research obj ect,and the steganographic method based on iSAC codec used in Gtalk was focused on.Hiding algorithm based on LPC parameters was established.Experimental results show that the proposed model can be applied to instant communication software that being commonly used,and extends the application range of information hiding based on VoIP.The LPC parameters hiding algorithm has a good hiding rate and better practicability.