基于噪聲的圖像人工退化研究.pdf

1、中國海洋大學碩士學位論文基于噪聲的圖像人工退化研究姓名：孫濤申請學位級別：碩士專業(yè)：計算機技術指導教師：解翠于愛國20090601基于噪聲的圖像人工退化研究ABSTRACTImageartificialdegradationisaprocesstoreducethevisualqualityofimagevoluntarilyandreversiblyforachievingthebusinessmodelwhichcalled‘try

2、andbuy’inimagebusinessThedegradedimagewasdistributedtoclientfreelyfortrialinthefirstplace，thenthedecryptionkeyoronlinereconstructionservicewouldbeprovidedteconstructtheoriginalimageiftheclientdecidestopayThismodelmakespr

3、ofitwithoutobeyingthe‘freeandshare’spiritinintemet，whichmakesa‘win—win’modelThispaperinvestigatesandanalyzestheimageartificialdegradationinselectiveencryptionThecontributionsofthispaperareasfollows：1Anovelschemebasedonim

4、agenoiseforimageartificialdegradationwasproposed，whichincludesboththeadditiveandmultiplicativenoiseThepredictorformulasforthedegreeofdegradationwereprovidedbyquantitativeanalyzingforbothtwomodelsExperimentconfirmsthattho

5、seformulasfittheactualvalue2TheanalysisandimprovementofthesecurityofthealgorithmbasedonimagenoisehadbeendoneTowithstandimagefilterattack，themixednoisewasintroducedFordefendingimageaveragingattack，theselecttempletisusedto

6、dualnoise3Atlast，thedeficienciesofthepaperwereproposedforfurtherworkThemostimportantjobofthepaperisthedegradationalgorithmbasedonimagenoiseThealgorithmispracticablebecauseitissimpleandfastThemoreimportantthingisthatthede

7、greeofdegradationCanbeaccuratelycalculatedAndintheadditivenoisemodel，thecompressionratioofdegradedimageCanbepredictedThosearenecessaryconditionsinbusinessapplicationItmeansthatthisalgorithmwhichalreadyowncertainapplicati