Based On The Frequency Domain Scrambling Encrypted Digital Image Watermark Algorithm

The digital watermark technique is a newly arisen information hiding of a technique.Because nowadays the information technique high speed development, the digital medium product(picture,audio,video ) is more and more widespread, people obtain the network to obtain these digital medium products more and easily, some persons copy,spread a work of have the copyright under the sistuation that didn't get admit probably.Be like a publication in the electronics sound so etc. realm, the copyright protection,the ownership attestation of the digital medium also is subjected to a value more and more.Adding to decrypt system traditionally can't resolve the copyright protection problem nicely also, because data once being decrypt is place in a control of decrypt the person completely under, the original creator has no replication that the way tracks a work with two disseminations.The robust of the watermark with can't seeing be the digital watermark is technical of two essential elements, the key technique that influences two main factors is the watermark structure that the digital watermark carries out strategy and structure.Study the watermark calculate way is to want to can't see under premise, embed watermark possibly and much.The key of the calculate way lies in the choice of the watermark and embed,embed the position and examination.This text has a foothold in the advanced result of domestic and international that realm, combining mathematics,password to learn ,the information theory etc. the knowledge of the related academics, mainly inquiried into concerning digital picture watermark to encrypt a technique.From the background,development,present condition and application etc.s elaborated the digital picture watermark technique to combine to carry on induce to the watermark calculate way with classification, was in the text put forward placing the calculate way of the place confusion and anti- transformation in addition, give the evaluation watermark embed the quantity of the strength to turn the calculation type, and with a kind of according to placed the frequency area transformation calculate way that the confusion encrypts a system to concretely practice a picture to encrypt and the DCT transformation is in the influence and the function in the digital watermark.This text mainly works to mainly is divided into an as follows four-part cent:1,digital watermark technical overview: See from related cultural heritage, the digital watermark carry out of the method have a lot of kinds.This text concretely tallied up the existing digital watermark technique and its characteristics in detail, and as to it's carry on the classification and rules whole, try to look for a suitable picture to conceal a method to provide some hide informations for aftertime.2, the digital picture place confusion to encrypt the technique and its result analysis:Place the confusion's encrypt is the digital picture encrypts a technique in of a little bit hot problem.The good and bad of the calculate way influences the result of its safety and other processing directly.This text discuss that place confusion to encrypt a method existingly, and combine the periodic of that method, put forward a kind of method that places confusion and anti- transformation to recover.Should place the disorderly instauration calculation quantity small, watermark instauration the efficiency is high.3 ,field transformation watermark technique:Analyzed DCT transformation principle,JPEG to compress calculate way in detail, combine the human vision system(HVS), embed the watermark transformation coefficient to the medium frequency part of carry the body picture, make the watermark embed strength is show in doing not cause the foundation with the sense of vision vigilance the exaltation, and release a kind of quality evaluation method that contains the watermark picture lately, use to evaluate to contain the watermark picture to lose genuine feeling condition.4,according to place the frequency field calculate way that the confusion encrypt in the application study in the digital watermark:This text analyzed to place confusion to encrypt a technique in detail to prepare the function in the processing in the digital watermark, putting forward making use of the actual application calculate way that the DCT field transformation conceals watermark.The exploitation embeds the concept of the strength, embeding strength to the different pixel adoption differently.The calculate way's safety is better, good digital picture's placing confusion to encrypt a technique can scatter a ratio availably an information especially, the DCT transformation calculate way can the effectively low holdout compress to transform with severals of attack, can recover a watermark information after the wave, add the voice.Along with digital watermark the formation of technical development and the relevant foundation theories research frame, its applied scale and realm will extend further, several of the in general use digital watermark calculate way to the signal processing,information transform currently and the malice attack have steady, can resist a form and the voice an attack, but all of them is according to the existing compression standard, for aftertime of higher compress calculate way and audio frequency compression, its steady can't get assurance.Therefore study watermark severals to lose really steady in the picture, the design can resist the watermark calculate way of various attack to reach agreement all steady problems definitely, will be a research direction of the digital watermark in very longly a period of time.