Based On Mpeg-2 Digital Video Watermark

Digital multimedia data supplies a world of convenience for the access of meltimedia data.Because digital pproducition is easy to be copied and tampered lawlessly,the information security and copyright protection of digital production is a problem crying for solution.Digital watermarking technology supplies a useful method for the copyright protection of digital production. At present,digital watermark have many results in the research about image digital watermark,but the researches on video and audio watermarking are few.Recently,digital video has already been a necessary entertainment method in our life,but the coresponding copyright protection has not grown mature yetThe research of copyright protection technology of digital viedo production become urgent,the research and development of video watermarking technology become more important.In this paper, some techniques about digital watermarking,the characters of video digital watermark and the current technical methods are disscussed.The paper introduces in detail the standard of MPEG-2 and date structure of MPEG-2,aims at the characters of the standard of MPEG-2,proposes a MPEG-2 video watermarking algorithm.By the way,.embedding and extracting watermark in compressed MPEG-2 video domain are carried out in VC development. When embedding,I frame is the localizations of the watemark,the watermark extraction process does not require the original video.The former users hash scrambling technology, chaos theory and spread frequency technology to do the watermark pretreatment.the algorithm embeds the watermark to direct current coefficients,and changes the chroma direct current coefficients according to their absolute values sef-asaptively.The algorithm use hash scrambling technology, chaos theory and spread frequency technology to video watermarking.The increase the invisibility,robustness and security of the watermark. The paper does the simulation experiments,then gives the result data and graphs. Lots of experiment results indicate the video vatermarking used the proposed algorithms can extract the watermark after sufered code rate change,frame regrouping,frame delering and other attacks. It shows the watermark has good robustness.At last, the thesis summarized all of research and have probed into the thchnology future developing direction of digital watermark.