Audio Authentication Watermarking Systems In The Lan Environment, The Design And Realization

With the advancing development of Internet and widely using of digital signal processing, the protection of digital information, especially multimedia, is becoming a crucial issue in information security.In consideration of the increasing values of information security, the issues in secret communication are studied in this dissertation. A voice authentication communication system, using digital signal processor, digital watermark algorithms and UDP/IP technique, is implemented.In this thesis, the techniques of information protection based on digital watermark and DSP are first briefly introduced. Based on existed DSP secrete communicaton research platform, a resolution for digital audio authentication communication,on which digital watermark technique is applied, is brought out. Every module is described in detail in the following chapter. Among many digital watermark algorithms, we select two typical schemes choicely. One is called sinusoidal pattern based spread spectrum watermark. In this algorithm, the watermark is embeded and detected in time field. The other algorithm is differential energy watermark (DEW for short). The embedding and detction of watermark is in frequence field. To reach the goal of network, UDP/IP protocols are successfully constructed in this system. With the analyzing of the feasibility and performance, such as operation speed, the corresponding adjustment is also applied. The outcome of intergrtion debugging indicate that our design is sucessful.Finally, the dissertation is concluded by pointing out some open issues on this secret communication system, as well as highlight some further improvement directions.