资源描述：
《级联迭代傅里叶变换算法在光学安全中的应用英文文献及翻译》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、14河南科技大学本科毕业设计（论文）AcascadediterativeFouriertransformalgorithmforopticalsecurityapplicationsAbstract:AcascadediterativeFouriertransform(CIFT)algorithmispresentedforopticalsecurityapplications.Twophase-masksaredesignedandlocatedintheinputandtheFourierd
2、omainsofa4-fcorrelatorrespectively,inordertoimplementtheopticalencryptionorauthenticityverification.Comparedwithpreviousmethods,theproposedalgorithmemploysanimprovedsearchingstrategy:modifyingthephase-distributionsofbothmaskssynchronouslyaswellasenla
3、rgingthesearchingspace.Computersimulationsshowthatthealgorithmresultsinmuchfasterconvergenceandbetterimagequalityfortherecoveredimage.Eachofthesemasksisassignedtodifferentperson.Therefore,thedecryptedimagecanbeobtainedonlywhenallthesemasksareunderaut
4、horization.Thiskey-assignmentstrategymayreducetheriskofbeingintruded.Keywords:Opticalsecurity–opticalencryption–cascadediterativeFouriertransformalgorithm1.IntroductionOpticaltechniqueshaveshowngreatpotentialinthefieldofinformationsecurityapplication
5、s.RecentlyRéfrégierandJavidiproposedanoveldouble-random-phaseencodingtechnique,whichencodesaprimaryimageintoastationarywhitenoise.ThistechniquewasalsousedtoencryptinformationinthefractionalFourierdomainandtostoreencryptedinformationholographically.Ph
6、aseencodingtechniqueswerealsoproposedforopticalauthenticityverification.WangetalandLietalproposedanothermethodforopticalencryptionandauthenticityverification.Unlikethetechniquesmentionedabove,thismethodencryptsinformationcompletelyintoaphasemask,whic
7、hislocatedineithertheinputortheFourierdomainofa4-fcorrelator.Forinstance,giventhepredefinitionsofasignificantimagef(x,y)asthedesiredoutputandaphase-distributionexp{jb(u,v)}intheFourierdomain,it’seasytooptimizetheotherphasefunctionexp{jp(x,y)}withamod
8、ifiedprojectionontoconstraintsets(POCS)algorithm[10].Thereforetheimagef(x,y)isencodedsuccessfullyintoexp{jp(x,y)}withtheaidofexp{jb(u,v)}.Inotherwords,thefixedphaseexp{jb(u,v)}servesasthelockwhiletheretrievedphaseexp{jp(x,y)}servesasthekeyofthesecuri
