Research On Algorithm Of Embedding And Extracting Multi-watermarking From Digital Audio Signal

Digital multimedia production's copyright have faced great challenge when the technology of it's storage and transmission progresses, especially when the Internet prevails. The research of digital watermarking becomes one of the hottest research topics, for it is useful to copyright protection and contents authentication. The watermarking system can embed sign information into the content of multimedia production by some algorithm, but it will neither affect originality's value or use, nor be perceived by people. This paper presents an algorithm of multi-watermarking for audio signal, in which robust and fragile watermarking are included. In this scheme, segment classification is used in the time domain, then the robust watermarking with different strength are embedded into the parts of low frequency DCT parameters in different audio segment according to the classification results. After that, appropriate quantization is used to produce the fragile watermarking. Experiments show that the two kinds of watermarking can respectively do their work well by proper control. The whole scheme is capable of associated protection to copyright. It can protect the copyright and estimate the originality of the audio signals. By the extraction of the watermarking, we can get two kinds of watermarking, one of them can be used to estimate the watermarked signal's origination,and the other one works well in copyright protection and is robust to many operations to digital signal, such as filter, resample and so on.