The Research Of Digital Audio Watermarking Technology Against Desynchronization Attacks

With the rapid development of the network technology (especially Internet) and the widespread use of multimedia information technology, the transmission of digital information (including digital audio, digital video, digital images, etc.) has become increasingly frequently. The following is that concerns of the people for the digital information security, because the digital information on the Internet can easily be modified, editing and replication, and that digital media copyright protection can not be protected effectively and suffered huge losses. Digital watermarking technology, considered as an effective complement solution for traditional encryption method, is a new technique for copyright protection and integrality authentication in the open network environment, is a digital multimedia intellectual property protection and effective means of security. In recent years, digital watermarking technology has caused people's attentions and is becoming an international academic focus. The so-called digital audio watermarking, is a technique that copyright information is embedded imperceptibly into the host media in a way that is robust to a variety of intentional or unintentional attacks. Digital audio watermarking is that embed the significance of a particular mark (watermark) into host audio by certain data processing method, and prove ownership of copyright information. It is effective to property information protection and digital multimedia security. With the development of digital audio watermarking technology, the various forms of attack also follows. How to better protect digital information and enhance the robustness of digital audio watermarking? Now, digital audio watermark technology is a major research for the robustness.In this paper, the main digital audio watermarking are as follows:1 A Content Based Audio Watermarking against Desynchronization Attacks. Firstly, the steady feature points are extracted from the host audio according to the local energy distribution. Then, the candidate audio segments for embedding watermark are defined by using feature points. Finally, the digital watermark is embedded into the host audio by modulating the statistics average value of audio samples. In digital watermark detection, the feature points are selected by the same technique as the embedding, and the digital watermark is extracted from the watermarked audio after the feature points.2 A robust content based audio watermarking using UDWT and invariant histogram. Firstly, the undecimated discrete wavelet transform (UDWT) is performed on original host audio. We extract low and high frequency information from the original host audio. Secondly, the invariant histogram is extracted from a selected wavelet coefficients range in the low frequency subband. Then, the bin of histogram is divided into many groups, each group including four consecutive bins. For each group, one watermark bit is embedded by reassigning the number of wavelet coefficients in this group of four bins. Finally, the digital watermark is embedded into the original audio signal in UDWT domain by modifying a small set of wavelet coefficients. The digital watermark is extracted from the histogram of the watermarked audio basis on relationship of four consecutive bins.