Application Of Digital Watermarking In Digital Archives

With the development of network and multimedia information processing technology, the digitization and cyberization of archival data is the main development trend of archival working in the information age. But because digital data can be easily replicated and disseminated widely, which will lead to abuse, altered or falsified. And the legitimate rights and interests of copyright owners have been infringed, such issues can not be ignored. To achieve effective protection of digital archives, to prevent illegal and improper use of digital archives, the introduction of digital watermarking technology.In this paper, two kinds of digital watermarking algorithm are utilized to achieve effective protection of digital archives:1. A digital watermarking algorithm based on discrete wavelet transform (DWT) is utilized in digital archives, which hides secret information in middle frequency coefficient. The algorithm makes the middle frequency coefficient of the host information grouping and calculates the mean of every group to makeup array B (W); followed by the array elements B (k)(k = 1,2,3,.. ..W) corresponding to the coefficient matrix with a choice of a factor. If the embedded watermark information is 1, make a>= B (k); If the embedded watermark information is 0, make a< B (k). Compare this whole array of B with the corresponding value of the coefficient, to put a watermark information into vector images. The result of experiment indicates that the algorithm is robust and a feasible scheme to achieve effective protection of digital archives.2. A digital watermarking algorithm based on discrete cosine transform (DCT) is utilized in digital archives. The basic idea is to extract the basic characteristics of watermarking image composition of auxiliary watermark, in order to determine whether the carrier image has been altered. Then split carrier image into 8×8 blocks, make these blocks of carrier image DCT. Finally, the relationship of the coefficient are utilized to embed watermark in the middle frequency and auxiliary watermark in the low frequency. Experimental results show that the algorithm can withstand multiple attacks, robust high, is a digital archive of achieving the dual purpose of copyright protection and reliability of real options.