简介：Thispaperpresentssomeresultsoftherelationbetweenwavelettransformandfractaltransform.Thewavelettransformoftheattractoroffractaltransformpossesestranslationalandscaleinvariance.Sowespeedthefractalimageencodingbytestingtheinvarianceofthewavelettransformappropriateforimageencoding.Theclassficationschemeofrangeblocksbywavelettransformisgiveninthispaper.

简介：Inimagereconstructionalgorithms,thechoicesoffilterfunctionsandinterpolatingfunctionsareveryimportantforthecomputationalspeedandthequalityoftheimagereconstructed,especially,forfan-beamgeometry,theoccurrenceofthesingularintegraloperatormayleadtosomegreatoscillationscomparedtotheoriginalimage.Inthispaperwewillgiveadirectconvolu-tionalgorithmwhichneedsnotthecomplexcomputationsoccuringintheFouriertransform,thenusingacircleintegralweobtainastablecomputationalprogram.Differentfromallotherpreviouswindowfunctionsusedbymanypioneerresearchers,inouralgorithmwechooseawindowfunctionsimilartoGabor'swindowfunctione-x^2/2,whichcanberegardedastheapproximationtotheinverseFouriertransformofalocallyintegrablefrequencyfunction.AlsowepointoutthatsuchreconstructionalgorithmprocedurescanbeusedtodealwiththeSPECTprojectiondatawithconstantattenuation.

简介：Anewsmoothingmethodisproposed.Thesmoothingprocessadaptstoimagecharacteristicsandisgoodatpreservinglocalimagestructures.Moreimportantly,inthetheoryundertheconditionsweakerthanthoseintheoriginalKacanovmethodanapproximalsequenceofsolutionstothevariationalproblemscanbeconstructedandtheglobalconvergencecanbeproved.AndtheconditionsinthepapersofSchn6rr(1994)andHeers,etal(2001)arediscussed.Numericalsolutionsofthemodelaregiven.

简介：Inthispaper,weproposeadiscrepancyrule-basedmethodtoautomaticallychoosetheregularizationparametersfortotalvariationimagerestorationproblems.Theregularizationparametersareadjusteddynamicallyineachiteration.Numericalresultsareshowntoillustratetheperformanceoftheproposedmethod.

简介：Weproposeanewalgorithmforthetotalvariationbasedonimagedenoisingproblem.ThesplitBregmanmethodisusedtoconvertanunconstrainedminimizationdenoisingproblemtoalinearsystemintheouteriteration.Analgebraicmulti-gridmethodisappliedtosolvethelinearsystemintheinneriteration.Furthermore,Krylovsubspaceaccelerationisadoptedtoimproveconvergenceintheouteriteration.Numericalexperimentsdemonstratethatthisalgorithmisefficientevenforimageswithlargesignal-to-noiseratio.

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简介：Thispaperinvestigatestherelative1-canonicalimageaofnon-hyperellipticfibrationsofgenus4.Itisprovedthatifafibreoftherelative1-caaonicalimage∑isnotacompleteintersectioninp^3thenthevariety∑cannotbesmoothonthisfibre.Moreover,twoexamplesaregiwntoshowtheoccurrenceofsuchcases.

简介：Inthispaper,westudyanoperatorswhichmapseveryn-by-nsymmetricmatrixA,toamatrixs(A_n)thatminimizes||B_n-A_n||FoverthesetofallmatricesB_n,thatcanbediagonalizedbythesinetransform.Thematrixs(A_n),calledtheoptimalsinetransformpreconditioner,isdefinedforanyn-by-nsymmetricmatricesA_n.Thecostofconstructings(A_n)isthesameasthatofoptimalcirculantpreconditionerc(A_n)whichisdefinedin[8],Thes(A_n)hasbeenprovedin[6]tobeagoodpreconditionerinsolvingsymmetricToeplitzsystemswiththepreconditionedconjugategradient(PCG)method.Inthispaper,wediscussthealgebraicandgeometricpropertiesoftheoperators,andcomputeitsoperatornormsinBanachspacesofsymmetricmatrices.Somenumericaltestsandanapplicationinimagerestorationarealsogiven.

简介：双树的复杂小浪变换是在信号并且图象处理的一个有用工具。在这份报纸，我们建议双树的复杂小浪变换(?WT)为图象inpainting的基于的算法问题。我们的途径基于蔡，禅宗，沈和Shens基于framelet的算法。复杂小浪变换在移动不变性，directionality和抗混叠的意义超过标准真实小浪变换。数字结果说明我们的算法的好表演。

简介：Imagerestorationisoftensolvedbyminimizinganenergyfunctionconsistingofadata-fidelitytermandaregularizationterm.Aregularizedconvextermcanusuallypreservetheimageedgeswellintherestoredimage.Inthispaper,weconsideraclassofconvexandedge-preservingregularizationfunctions,I.e.,multiplicativehalf-quadraticregularizations,andweusetheNewtonmethodtosolvethecorrespondinglyreducedsystemsofnonlinearequations.AteachNewtoniterate,thepreconditionedconjugategradientmethod,incorporatedwithaconstraintpreconditioner,isemployedtosolvethestructuredNewtonequationthathasasymmetricpositivedefinitecoefficientmatrix.Theigenvalueboundsofthepreconditionedmatrixaredeliberatelyderived,whichcanbeusedtoestimatetheconvergencespeedofthepreconditionedconjugategradientmethod.Weuseexperimentalresultstodemonstratethatthisnewapproachisefficient,andtheeffectofimagerestorationisr0easonablywell.