The Studies And Application Of The Digital Audio Watermarking Technology

With the development of the internet and multimedia, the protection for the intellectual copyright is becoming more and more urgent, and the digital watermarking is the effective means to solve the problem. It is a technique by which some secret information is embedded into the host signal (text, audio, image or video) as to protect the copyright of digital product, approve the reliability of product, trace the illegal-copy behavior or offer product additional information. The secret information may be copyright symbols, user's license or some information relative to products.With the two-dimension binary image as watermarking information, the audio data as embedded target, on the basis of analyzing the digital technological characteristic and demand of audio watermarking in detail, in order to enhance the imperceptible and robust of the digital watermarking, by utilizing the spatiotemporal frequency and multi-resolving-power characteristic of one-dimension discrete wavelet transform, and integrating the Human Auditory System(HAS), a blind audio digital watermarking algorithm based on wavelet transform is presented. First, the watermarking image has been processed by pseudorandom permutation, and then converted it into a one-dimension sequence; second, the audio data has been divided and discrete wavelet transform, the watermarking is embedded into the high-frequency sub band by modifying the parity of the original audio signal wavelet coefficients. The watermark can be extracted without the original audio signal. This helps it to use in the actual project. This algorithm is simple and general. Experiment show that the watermarking is imperceptible and robust against some common signal processing operations.On the base of the theory of the algorithm suggested by the author, the digital audio watermark system is designed and completed in this paper by using MATLAB and LabVIEW based on virtual instrument. The technology can be used to solve the matter of copyright and identification in spreading audios by Internet and other digital media. So the study of this thesis is very meaningful and socioeconomic benefit.