Information Hiding And Digital Audio Watermarking

With the rapid development of the digital and network techniques, the information hiding technology has become a hotspot the current information science field. Although the conventional data encryption techniques maybe partially prevent the work be unauthorized released, almost all the data encryption technologies are crisis with the rapid enhance of the deciphering technique. Most hackers are bursting to attack the encrypted data as long as they find it, so that the encrypted data and the original data are same hazard. Moreover, when we need to use the carrier data to check the validity and the authorized information while the carrier data is used in gear, the conventional data encrypt techniques is inefficient.The data hiding technique will reduce the dangers of the hidden data. Firstly, nobody can know the hidden data except the author. This will not blaze the other's excitements to attack. Secondly, the hidden data would not be gone round even if the carrier data were destroyed.Digital watermark is one of the hiding technologies. The technology embeds some data into a carrier data, and these data can be checked with some methods. So the embedded information should not interfere the carrier data be used in gear, as which is named invisible. Also, the carrier data might be compressed or be processed so as to suit many requirements. Even under these situations, the watermark should still be checked, which is called as robustness. By several years hard investigate, it have been proved that watermark techniques must be noninvertible, otherwise, the correctness and singleness of the embedded information would can not be guaranteed, and so it's truths would be problem. Thereafter, a watermark detection technique based on statistic changed this situation. This technology uses only the carrier data to check embedded information so it can assure the noninvertible checking. But this technology is base on the fact that random sequences are less correlation, so the attacker also may gain his ends by sounds out all the possibility even though the false alarm detection probability is very small. Therefore, how to reduce such possibility in effect has become the research keystone. This paper strengthen the noninvertible of the create process of watermark information, and adopt the dynamic chaos theory to generate the random sequence which is used as the watermark information. This ensures the stochastic behavior of the random sequence. In addition, this paper gives an association watermark technology to reduce the false alarm detection probability, which correlates the watermark information sequence and the watermark position sequence, and employs double channels technique to hiding or checking watermark. Through theoretical analysis and experiment study, the association watermark technology was confirmed that it could improve the reliability and the security of watermark. Further because this technology could cut short the length of embedded information, it also could assure the watermark be invisible in some degree. Synchronization is an important problem of digital audio watermarking. This paper gives a new method for digital audio watermarking which uses audio cepstum domain and energy features to decide the location of embed frames. The simulation results verified that the method improved the robustness resisting the attacks such as MP3 compression, time scaling, pitch shifting and cutting samples.