結(jié)合分形編碼的DCT域圖像水印算法研究.pdf

1、重慶大學(xué)碩士學(xué)位論文結(jié)合分形編碼的DCT域圖像水印算法研究姓名：吳俊峰申請學(xué)位級別：碩士專業(yè)：應(yīng)用數(shù)學(xué)指導(dǎo)教師：何傳江20070420重慶大學(xué)碩學(xué)位論文英文摘要ABSTRACTWiththedevelopmentofcomputernetworksandthecommunicationtechnologydigitalworks，suchasimage，videoandaudio，maybeobtainedeasilyatthesame

2、timegageistakentoprotectcopyrightsoftheseworksandpreventthepirateTherefore，di百talwatermarktechniqueisbroughtforwardtoprotectthelegitimaterightofownerofworkFractalimagecodingisaverypromisingimagecompressiontechniqueDuetoi

3、tsnoveltyhighcompressionrateresolutionindependenceandfastdecodingthetechniquehasreceivedmoreinterestsfiomtheresearchersintheareaofimageprocessingespeciallyimagecompressionOVerthepastdecadeNowfractalimagecodinghasspreadOV

4、erotherareasofimageprocessingInthisdissertation，somebasicknowledgeofdigitalwatermarkingtechniquesisfirstsystematicallydiscussed，includingitsbackground，generalsystemstructurebasicprinciplestateoftheartandtlleirapplication

5、sTwoadaptiveimagewatermarkingalgorithmscombiningDiscreteCosineTransform(DCT)andfractalcodingarethenproposedIndetail，thehostimageissplitintononoverlappingfixedsizesquareblocks，whichalecategorizedintotwoclassesaccordingtom

6、eircollageerrorsobtainedbyperformingbaselinefiactalcodingTheblocksclassificationisutilizedtoformafeaturemarkofthehostimageanddetermineimbeddingstrengthsofthewatermarkindistinctblocksandArnoldtransformisappliedtoscrambleb

7、oththefeaturemarkandbinarycopyrightsymb01Thewatermarkisthefusionofthescrambledfeaturemarkandascrambledbinarycopyrightsymbol(usingXORoperation)LastthewatermarksareembeddedintothemiddlefrequencybandsofDCTdomainsofdistinctb

8、locksbycomparingtheselectedthreecoefficientsorqualifyingtheDCcoefficientsInordertotesttheimperceptibilityandrobustnessofthealgorithms，computersimulationsonthetwoalgorithmsareconductedrespectivelyThesimulationresultsindic

9、atethatthewatermarkingalgorithmsarebothimperceptibleandrobusttocommonattackssuchasJPEGcroppingGaussianfilteringnoisingetoKeywords：watermarkingfractalcodingdiscretecosinetransform(DCT)，DCcoefficients，middlefrequencycoeffi