基于單向hash函數(shù)的脆弱數(shù)字水印研究.pdf

1、南開大學碩士學位論文基于單向hash函數(shù)的脆弱數(shù)字水印研究姓名：楊群亭申請學位級別：碩士專業(yè)：計算機應用技術(shù)指導教師：高鐵杠20090501ABSTRACT———————————————————————————————————————————————————一一AbstractWiththerapiddevelopmentofcomputernetworkandmultimediateehnologyitismoreconvenient

2、tothedisseminationofdigitalproductsHoweverthiswillleadtomoreissuesofpiracyandinformationtamperforsomeinterestsobjectivelyAsone0Itheimportantapplicationsofinformationhidingtechnologyincomputerfielddigitalwatermarkingprovi

3、desanewmethodtoprotectthecopyrightofmultimediainformationItembedswatermarksintodigitalmultimediaandcarriesoutt11efunctionssuchasinformationhidingsecretstoringandcopyrightprotectionbydetectingthewatermarksthatcalltrack廿le

4、useofdigitalmultimediaDigitalwatermarkingsystemWasintroducedatfirstItincludesthedigitalwatermarkingmodel，evaluationstandard，classificationattacks，applications，andSOonThenthechaostheoryWasintroducedandanalyzedThemainconte

5、ntsincludetheoriginanddevelopment，definition，theessentialfeatureofchaosAhashfunctionconstructionmethodbasedoncellneuralnetworkwimhyperchaoscharacteristicsisproposedThedetailedanalysisisperformed，whichpresentstheonewayhas

6、hfunctionbasedonproposedalgorithmpossessesgoodperformancesofanti—attackanddiffusionMeanwhile，alterablelengthonewayhashfunctioncouldbegeneratedbyproposedalgorithmandsimulationfortheprocessshowsitseffectivenessandvalidityo

7、fouralgorithminvariousconditionsThefragileimagewatermarkingalgorithmbasedononewayhashfunctionisrepresentedinthispaperThefragileimagewatermarkingalgorithmisspatialdomainbasedTheLSBpanelissetto0firstTheremainingvalueofpixe

8、lsineveryrowandcolunmareregardasplaintextsofonewayhashfunctionandthengetseriesof128bitshashcodeGettheweightofevery128bitshashcode，andtheeveryweightvaluecanbepresentby8bitsTheseriesbitsCanbeembeddedintheLSBpanelThetamperp