资源描述：
《数字图像处理,冈萨雷斯,课件英文版 Chapter05 图像复原.ppt》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。
1、DigitalImageProcessingChapter5:ImageRestoration23June2006(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalImageProcessing,2ndEdition.ConceptofImageRestorationImagerestorationistorestoreadegradedimagebacktotheoriginalimagewhileimageenhancementistomanipulatetheimagesothat
2、itissuitableforaspecificapplication.Degradationmodel:whereh(x,y)isasystemthatcausesimagedistortionandh(x,y)isnoise.NoiseModelsNoisecannotbepredictedbutcanbeapproximatelydescribedinstatisticalwayusingtheprobabilitydensityfunction(PDF)Gaussiannoise:RayleighnoiseErlang(Gamma
3、)noiseNoiseModels(cont.)ExponentialnoiseUniformnoiseImpulse(salt&pepper)noise(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalImageProcessing,2ndEdition.PDF:StatisticalWaytoDescribeNoisePDFtellshowmucheachzvalueoccurs.(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalI
4、mageProcessing,2ndEdition.ImageDegradationwithAdditiveNoiseOriginalimageHistogramDegradedimages(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalImageProcessing,2ndEdition.OriginalimageHistogramDegradedimagesImageDegradationwithAdditiveNoise(cont.)(ImagesfromRafaelC.Gonz
5、alezandRichardE.Wood,DigitalImageProcessing,2ndEdition.PeriodicNoisePeriodicnoiselookslikedotsInthefrequencydomain(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalImageProcessing,2ndEdition.EstimationofNoiseWecannotusetheimagehistogramtoestimatenoisePDF.Itisbettertouset
6、hehistogramofoneareaofanimagethathasconstantintensitytoestimatenoisePDF.(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalImageProcessing,2ndEdition.PeriodicNoiseReductionbyFreq.DomainFilteringBandrejectfilterRestoredimageDegradedimageDFTPeriodicnoisecanbereducedbysettin
7、gfrequencycomponentscorrespondingtonoisetozero.(ImagesfromRafaelC.GonzalezandRichardE.Wood,DigitalImageProcessing,2ndEdition.BandRejectFiltersUsetoeliminatefrequencycomponentsinsomebandsPeriodicnoisefromthepreviousslidethatisFilteredout.(ImagesfromRafaelC.GonzalezandRicha
8、rdE.Wood,DigitalImageProcessing,2ndEdition.NotchRejectFiltersAnotchrejectfilterisusedtoeliminate
