Digital Watermarking Technology Application In Image Encryption

With the wide application of net work technology and digitalization of information media ,Digitalized information can be conveniently and quickly transferred to every part of the world with the assistance of computers, digital scanners, numeral cameras, etc. Furthermore it is highly possible for fully duplication and widespread transferring of digital images, audio and visual digital products through the network. However, when digital files or products are being transferred on the Internet, some malicious personnel or groups may try to duplicate and disseminate copyright contents without authorization. Therefore, it has become an urgent issue as to how to provide a limited and effective protection for digital products and also how to maintain a secure communication system. Meanwhile, conventional data encryption techniques seem unable to keep an effective checking and tracking for some data's legality and their property rights when a normal employment of these data is required.With the development of modern data hiding technique, the protection of various information based on similar nature-color-protection principle will greatly reduce the danger of hidden data. Firstly, nobody, except the author, knows that there have hidden data. Consequently, the others will not be spurred to decrypt the data. Secondly, the hidden data would not be disseminated even if the carrier data were destroyed.Digital watermark is one of the hiding techniques. The technique embeds some data into a carrier data, and these data can be checked any time with some methods. Therefore, the embedded information, as required, should not interfere the normal use of the carrier data, and this is the hiding requirement of watermark technique. Also, the carrier data might be compressed or be processed so as to suit various requirement. Even under these situations, the watermark should still be checked, which is called as robustness. After many researchers' hard work for several years, it have been proved that watermark techniques must be noninvertible, otherwise, the correctness and uniqueness of the embedded information can not be guaranteed, and thus it's authenticity would be doubtful.Since transparency and excellect effect are the tow contradictory sides of...