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ID:34369461
大小:1.48 MB
页数:8页
时间:2019-03-05
《利用参考图像的遥感图像模糊估计与恢复》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、WANGTianhuieta1.:Blurestimationandrestorationofremotesensingimagesusingareferenceimage461(m,)P(YlYc;h,)~N(n310,),(7)0rP(Yl;,)=e坤Fig.1Degradationmodelinimageacquisition[_]’㈣whereHisthedegradationfunctionintheformofcircularmat—Fromthemodel,wecangetthedegrad
2、ationequationrix.Takelogarithmoperationtobothsidesoftheaboveequa-Y=x圆h+/1,(1)tion,andwehavewhere0denotestheconvolutionoperationandlisusedins—一teadofnonlyfortheconvenienceoflateruse.专枷·Nowletbeablurfreeimageofthesamescene,i.e.,(y-臌)一mIno-2+ch0-1,thenthefol
3、lowingequationholds.2,(9)whereMistheimagesizeandCisaconstant.Wecangetano—=x0%+n2+2,(2)wherewealsoassume,tobeGaussianwhitenoiseofzerotherestimationexpressionbysubstituteEq.(6)toEq.(9),i.e.,mean.盯gmin{(y城W_ethenobtainfromEq.(1)andEq.(2)thatY=0h+n3.(3)Noten3
4、isGaussiannoiseofzeromean,forGaussiannoise()+M}.(10)alwaysremainGaussianwhenitpassesalinearsystem.Butn3Theequationabovecanbeinducedtoalinearsystemaboutdoesnotnecessarilyremainwhite,whichfortunatelyhasnohandwhosesolutionisunique,ontheconditionthattheefecto
5、nourfollowingdiscussion.degradationfunctionissymmetricand≥0,∑f=landhhasWecanseefromEq.(3)thatthetaskofblindPSFestima-tionisconvertedtoadeconvolutionproblem,thankstoablur2.3Restorationfreeimageofthesamescene(norequirementonnoise),thatis,theestimationofh,gi
6、venyand.AfterhavingfinishedthePSFestimation,wecanusetheAftertheestimationofhiscompleted,therestorationofTotalVariation(TV)regularizationmethod(Zou,2001)tores—becomesasimilardecOnvO1utiOntask,i.e.,toestimatex,knowntoretheoriginalimage.Thismethodcanbetterpr
7、eservetheYandh,accordingtoEq.(1).detailinformationontheimageandsuppressthenoise.The2.2PSFestimationcostfunctionis,(/)=1Jrg一酬l+l+,(11)IfweestimatePSFwithregularizationmethod,wehavetodealwithaniterativeoptimizationprocedure,owingtothewherefandgarethefimctio
8、naloftheundistortedimageandrestrictionsonhsuchasnon—negative,normalizedandfinitetheobservednoisyandblurredimage,respectively,Kisthesupported(Yuaneta1.,2007).Thatiswhatwetrytoavoid,bluroperator.Visthegradientoperator
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