简介:Inthispaper,weproposeasparseovercompleteimageapproximationmethodbasedontheideasofovercompletelog-Gaborwavelet,meanshiftandenergyconcentration.Theproposedapproximationmethodselectsthenecessarywaveletcoefficientswithameanshiftbasedalgorithm,andconcentratesenergyontheselectedcoefficients.Itcansparselyapproximatetheoriginalimage,andconvergesfasterthantheexistinglocalcompetitionbasedmethod.Then,weproposeanewcompressionschemebasedontheaboveapproximationmethod.TheschemehascompressionperformancesimilartoJPEG2000.TheimagesdecodedwiththeproposedcompressionschemeappearmorepleasanttothehumaneyesthanthosewithJPEG2000.
简介:Inlandmark-basedimageregistration,estimatingthelandmarkcorrespondenceplaysanimportantrole.Inthisletter,anovellandmarkcorrespondenceestimationtechniqueusingmeanshiftalgorithmisproposed.Imagecornerpointsaredetectedaslandmarksandmeanshiftiterationsareadoptedtofindthemostprobablecorrespondingpointpositionsintwoimages.Mutualinformationbetweenintensityoftwolocalregionsiscomputedtoeliminatemis-matchingpoints.Multi-levelestimation(MLE)techniqueisproposedtoimprovethestabilityofcorrespondingestimation.Experimentsshowthattheprecisioninlocationofcorrespondencelandmarksisexact.Theproposedtechniqueisshowntobefeasibleandrapidintheexperimentsofvariousmono-modalmedicalimages.
简介:摘要视频数据分析是监控系统中的重要组成部分,监控系统分析视频的第一步是区分对象,第二步是跟踪对象,最后一步是分析对象行为。本文采用改进的MeanShift算法对行人进行跟踪。
简介:Themeanshifttrackerhasdifficultyintrackingfastmovingtargetsandsuffersfromtrackingerroraccumulationproblem.Toovercomethelimitationsofthemeanshiftmethod,anewapproachisproposedbyintegratingthemeanshiftalgorithmandframe-differencemethods.Theroughpositionofthemovingtargetisfirstlocatedbythedirectframe-differencealgorithmandthree-frame-differencealgorithmfortheimmobilecamerascenesandmobilecamerascenes,respectively.Then,themeanshiftalgorithmisusedtoachieveprecisetrackingofthetarget.Severaltrackingexperimentsshowthattheproposedmethodcaneffectivelytrackfirstmovingtargetsandovercomethetrackingerroraccumulationproblem.
简介:ItisshowninthispaperthatahyponormalweightedshiftofnormoneisunitarilyequivalenttoaToeplitzoperatorifandonlyifitsweights{an}0∞satisfy1-丨an丨2=(1-丨a0丨2)n+1n≥0.Inparticular,thisanswerstheAbrahamse’sProblem2.Asaconse-quence,the(surprising)answer,obtainedfirstbyC.C.Coweninanexplicitform,toHalmos’Question5isrecaptured.
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简介:ThereseearchontherelationbetweenweightedshiftoperatorsonHilbertspacesandotherimportantclassofoperatorsattractedtheattentionofsomemathematicians.Forexample,therelationbetweenweightedshiftoperatorsandsubnormaloperatorshasbeenthoroughlystudiedbyJ.Stampfli,R.GellarandD.A.Herrero,etc.(seereference[1])Butthedecomposabilityofweightedshiftoperatorshasnotyetattractedenoughattentionuptonow.Wemadeinitialresearch