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269 个结果
  • 简介:[1]Ci,S.,Sharif,H.,2002.AVariableDataRateSchemetoEnhanceThroughputPerformanceofWirelessLANs.IEEECSNDSP.[2]Doufexi,A.,Armour,S.,Butler,M.,Nix,A.,Bull,D.,2001.AstudyoftheperformanceofHiperlan/2andIEEE802.11aphysicallayers.IEEEVTC,1:668-672.[doi:10.1109/VETECS.2001.944927][3]Doufexi,A.,Armour,S.,Karlsson,P.,Butler,M.,Nix,A.,Bull,D.,2002.AcomparisonoftheHiperlan/2andIEEE802.11aWirelessLANstandards.IEEECommunicationsMagazine,40(5):172-180.[doi:10.1109/35.1000232][4]Ferré,P.,Doufexi,A.,Chung-How,J.,Nix,A.,Bull,D.,2003.LinkAdaptationforVideoTransmissionoverCOFDMBasedWLANs.IEEESCVT.Eindhoven.[5]Girod,B.,Kalman,M.,Liang,Y.,Zhang,R.,2002.Advancesinchannel-adaptivevideostreaming.JournalofWirelessCommunicationsandMobileComputing,2(6):573-584.[doi:10.1002/wcm.87][6]Haratcherev,I.,Langendoen,K.,2004.HybridRateControlforIEEE802.11.ACMInternationalWorkshoponMobilityManagementandWirelessAccess(MobiWac),Philadelphia.[7]Haratcherev,I.,Langendoen,K.,Lagendijk,I.,Sips,H.,2002.D3.16:Application-directedAutomatic802.11RateControl.GigaMobileProject,TUDelf,Tech.Rep.[8]Haratcherev,I.,Langendoen,K.,Lagendijk,R.,Sips,H.,2004.SNR-basedRateControlinWaveLAN.ASCI2004Conference.PortZelande.[9]Haratcherev,I.,Taal,J.,Langendoen,K.,Lagendijk,R.,Sips,H.,2005.AutomaticIEEE802.11ratecontrolforstreamingapplications.WirelessCommunicationsandMobileComputing,5(4):421-437.[doi:10.1002/wcm.301][10]Hoffman,C.,Manshaie,M.H.,Turletti,T.,2005.CLARA:Closed-LoopAdaptiveRateAllocationforIEEE802.11WirelessLANs.IEEEWirelessCom'.Hawaii.[11]Holland,G.,Vaidya,N.,Bahl,P.,2001.ARate-AdaptiveMACProtocolforMulti-HopWirelessNetworks.Mobicom.Rome.[12]H264software,2005.H.264/AVCSoftwareCoordination.http://bs.hhi.de/~suehring/tml/.[13]IEEE802.11,1999.Part11:WirelessLANMediumAccessControl(MAC)andPhysicalLayer(PHY)Specifications.[14]IEEE802.11a,1999.Part11:WirelessLANMediumAccessControl(MAC)andPhysicalLayer(PHY)Specific

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  • 简介:高效地利用单个说明的性能为录像编码的多重数据(SIMD)体系结构,有power-of-two存储器模块的并联存储器体系结构被建议。扭曲计划在水平、垂直的方向提供没有冲突的存取给邻近的元素(8位和16位数据类型)或与power-of-two间隔采用二篇小说,它不在以前的并联存储器体系结构是可能的。区域消费和延期评价与4,8和16个记忆模块分别地被给。在一种0.18-μm互补金属氧化物半导体技术下面,当读了并且写潜伏时,合成结果证明建议系统能以19k门的成本与16个记忆模块完成230MHz钟频率分别地是3和2个钟周期。我们在一个录像信号处理器(VSP)上实现建议并联存储器体系结构。VSP与建议建筑学提高了的结果表演为H.264完成1.28×加速即时译码。

  • 标签: 视频 编码 单指令多数据 平行记忆 相位差
  • 简介:Theauthordesignedtwoalgorithmsfordistributedcooperationamongmultiplevideostreamssharingcommoncommunicationresources.Thealgorithmstakeadvantageofanoptimizationframeworkthatcharacterizesvideopacketssuchthatjointresourceallocationcanbeimplementednotonlyoverthepacketsofasinglestream,butalsoacrosspacketsofdifferentstreams.Thefirstalgorithmenablescollaborationamongmultiplevideosendersinan802.11CSMA/CAwirelessnetworksuchthattheirjointperformanceismaximized.Viathealgorithm,theuserscooperativelyestablishtransmissionprioritiesbasedontheassignedcharacterizationsoftheirvideopackets.Thesecondtechniqueallowsforlow-complexityjointbandwidthadaptationofmultiplevideostreamsatintermediatenetworknodesintheIntemetinordertomaximizetheoverallnetworkperformance.Theauthoranalyzestheadvantagesoftheproposedalgorithmsoverconventionalsolutionsemployedinsuchscenarios.Itisshownthatdependingonsystemparameterssuchasavailablenetworkdataratetheproposedtechniquescanprovidesubstantialgainsinend-to-endperformance.

  • 标签: MEDIA cooperation DISTRIBUTED video streaming Wireless
  • 简介:Sportsvideoappealstolargeaudiencesduetoitshighcommercialpotentials.Automaticallyextractingusefulsemanticinformationandgeneratinghighlightsummaryfromsportsvideotofacilitateusers'accessingrequirementsisanimportantproblem,especiallyintheforthcomingbroadbandmobilecommunicationandtheneedforuserstoaccesstheirmultimediainformationofinterestfromanywhereatanytimewiththeirmostconvenientdigitalequipments.Inthispaper,asystemtogeneratehighlightsummariesorientedformobileapplicationsisintroduced,whichincludeshighlightextractionandvideoadaptation.Inthissystem,severalhighlightextractiontechniquesareprovidedforfieldsportsvideoandracketsportsvideobyusingmulti-modalinformation.Toenhanceusers'viewingexperienceandsavebandwidth,3Danimationfromhighlightsegmentisalsogenerated.Asanimportantproceduretomakevideoanalysisresultsuniversallyapplicable,videotranscodingtechniquesareappliedtoadaptthevideoformobilecommunicationenvironmentanduserpreference.Experimentalresultsareencouragingandshowtheadvantageandfeasibilityofthesystemformultimediacontentpersonalization,enhancementandadaptationtomeetdifferentuserpreferenceandnetwork/devicerequirements.

  • 标签: VIDEO analysis VIDEO transcoding HIGHLIGHT summary
  • 简介:Thispaperproposesanewadaptivepost-filteringalgorithmtoremovecodingartifactsinblock-basedvideocoder.Theproposedmethodconcentratesonblockingandringingartifactsremoval.Forde-blocking,theblockingstrengthisidentifiedtodeterminethefilteringrange,andthemaximumquantizationparameteroftheimageisusedtoadaptthe1Dfuzzyfilter.Forde-ringing,besidestheedgedetection,acomplementaryringingdetectionmethodisproposedtolocatetheneglectedringingblocks,andthegradientthresholdisadoptedtoadjusttheparameterof2Dfuzzyfilter.ExperimentsareperformedontheMPEG-4sequences.Comparedwithothermethods,theproposedoneachievesbetterdetailpreservationandartifactsremovalperformancewithlowercomputationalcost.

  • 标签: 自适应模糊滤波器 视频 图象 编码器 振铃效应 块效应
  • 简介:WesolvetheproblemofuplinkvideostreaminginCDMAcellularnetworksbyjointlydesigningtheratecontrolandschedulingalgorithms.Inthepricing-baseddistributedratecontrolalgorithm,thebasestationannouncesapricefortheperunitaveragerateitcansupport,andthemobiledeviceschoosetheirdesiredaveragetransmissionratesbybalancingtheirvideoqualityandcostoftransmission.Eachmobiledevicethendeterminesthespecificvideoframestotransmitbyavideosummarizationprocess.Inthetime-division-multiplexing(TDM)schedulingalgorithm,thebasestationcollectstheinformationonframestobetransmittedfromalldeviceswithinthecurrenttimewindow,sortstheminincreasingorderofdeadlines,andschedulesthetransmissionsinaTDMfashion.Thisjointalgorithmtakesadvantageofthemulti-usercontentdiversity,andmaximizesthenetworktotalutility(i.e.,minimizethenetworktotaldistortion),whilesatisfyingthedeliverydeadlineconstraints.Simulationsshowedthattheproposedalgorithmsignificantlyoutperformstheconstantrateprovisionalgorithm.

  • 标签: VIDEO streaming Pricing UPLINK communications CDMA
  • 简介:这篇文章开发一个模型在连续时间经济检验时间矛盾问题的平衡行为与随机并且endogenized失真。首先,作者介绍顺序合理的平衡的观点,并且证明时间矛盾问题可以为随机的设定与扳机名声策略被解决。为顺序合理的平衡的存在的条件被提供。然后,顺序合理的随机地稳定的平衡的概念被介绍。作者比较在合作行为和不合作的行为之间的相对稳定性,并且证明在这场钱的政策比赛的合作平衡是顺序合理的随机地稳定的平衡,不合作的平衡是顺序合理的随机地不稳定的平衡。长远来说,零通货膨胀钱的政策内在地比谨慎规则更稳定,并且曾经证实他们趋于为时间的更长的时期坚持。

  • 标签: 货币政策 推测稳定平衡 时间矛盾 最优终止
  • 简介:BymeansofthefrozentimeapproachandtheKroneckerproduct,twocriteriaofasymptoticstabilityarederivedforthelinear,timevariantdynamicsystemswitheithershorttimedelaysorwithweakfeedbackinvolvingarbitrarytimedelays,respectively.Itisfoundthattheasymptoticstabilityoftheseretardeddy-nainicsystemsisgovernedbythemaximalandminimalsingularvaluesofthecoeffi-cientmatricesandtheirtimederivatives.

  • 标签: TIME DELAY STABILITY FROZEN TIME approach
  • 简介:OPTIMALMODELSFORTHEFIRSTARRIVALTIMEDISTRIBUTIONFUNCTIONINCONTINUOUSTIME-WITHASPECIALCASELINYUANLIE(林元烈)(DepartmentofAppliedMa...

  • 标签: MARKOV decision process FIRST ARRIVAL time distribution
  • 简介:students'mathematicalunderstanding,theyarenotableyettomastertothenextdegree.Thedecreasingofstudents'MathqualitycanbeseenonthesurveydataonProgramforInternationalStudentAssessment(PISA)thatconductedeachofthreeyears.On2003,Indonesiawasinthe38^thfrom40stateswiththescore360.On2006,itwasin50thfrom57stateswiththescore391.

  • 标签: 数学 系统科学
  • 简介:为多看法录像编码的一个新奇颜色赔偿方法(MVC)被建议,它高效地与照相机的差异引起的颜色失配的存在利用在看法之间的会见相关性。一个颜色赔偿模型在红绿蓝隧道被开发然后为实际使用延长了到YCbCr隧道。一幅修改会见参考图画基于颜色赔偿模型被构造,它比原来的会见参考图画更类似于编码图画。而且,颜色赔偿因素能在编码器和解码器被导出,因此,没有另外的数据需要被传给解码器。试验性的结果证明建议方法改进MVC的编码效率并且维持好主观质量。

  • 标签: 多视频编码 色彩补偿 照相机 多样性
  • 简介:Real-timevideotransportoverwirelessInternetfacesmanychallengesduetotheheterogeneousenvironmentincludingwirelineandwirelessnetworks.Arobustnetworkconditionclassificationalgorithmusingmultipleend-to-endmetricsandSupportVectorMachine(SVM)isproposedtoclassifydifferentnetworkeventsandmodelthetransitionpatternofnetworkconditions.End-to-endQuality-of-Service(QoS)mechanismslikecongestioncontrol,errorcontrol,andpowercontrolcanbenefitfromthenetworkconditioninformationandreacttodifferentnetworksituationsappropriately.TheproposednetworkconditionclassificationalgorithmusesSVMasaclassifiertoclusterdifferentend-to-endmetricssuchasend-to-enddelay,delayjitter,throughputandpacketloss-ratefortheUDPtrafficwithTCP-friendlyRateControl(TFRC),whichisusedforvideotransport.Thealgorithmisalsoflexibleforclassifyingdifferentnumbersofstatesrepresentingdifferentlevelsofnetworkeventssuchaswirelinecongestionandwirelesschannelloss.Simulationresultsusingnetworksimulator2(ns2)showedtheeffectivenessoftheproposedscheme.

  • 标签: VIDEO transport END-TO-END QoS WIRELESS Internet
  • 简介:最近的研究证明了联机录像成像是为监视结晶化过程的一种很有希望的技术。当需要柔韧、快、有能力处理的图象分析由于操作象混合和稳固的集中那样的条件的时间的变化改变了图象质量,在为即时靠近环的控制使用这种技术的瓶颈被考虑。因为晶体趋于重叠或属于对方,在高固体的集中的图象分析结果极其挑战性,在晶体之间的边界通常是模糊的。这篇论文论述能有效地处理在高固体的集中拿的图象的一个图象分割算法。方法片断晶体在水晶块的轮廓上沿着主要相关的凹面点属于对方。详细过程在一个热阶段的反应堆用申请被介绍给l-glutamic酸的结晶化。

  • 标签: 分析方法 图象 处理技术 结晶化
  • 简介:ThenewH.264videocodingstandardachievessignificantlyhighercompressionperformancethanMPEG-2.AstheMPEG-2ispopularindigitalTV,DVD,etc.,bandwidthormemoryspacecanbesavedbytranscodingthosestreamsintoH.264intheseapplications.Unfortunately,thehugecomplexitykeepstranscodingfrombeingwidelyusedinpracticalapplications.Thispaperproposesanefficienttranscodingarchitecturewithasmartdownscalingdecoderandafastmodedecisionalgorithm.Usingtheproposedarchitecture,hugebufferingmemoryspaceissavedandthetranscodingcomplexityisreduced.Performanceoftheproposedfastmodedecisionalgorithmisvalidatedbyexperiments.

  • 标签: 图像通信 视频自动译码 代码转换机 电子技术
  • 简介:Timereversalisappliedtotheunderwaterspreadingspectrumcodingcommunication.Onthebaseofanalyzingthefocusingcharacteristicsofthetimereversalinunderwaterwaveguide,thetimereversalisstudiedtoovercomethewavedistortionoftheencodedsignalcausedbythemulti-patheffect.TheexperimentresearchforunderwatercodingcommunicationiscarriedoutinalabwatertankandthecorrespondingtheoreticalanalysisisalsoconductedbyBinaryPhaseShiftKeying(BPSK)encodingandBarkercodewith7chipsforthespreadingspectrumsignal.Theresultsshowthatthetimereversalcanimprovethefocusinggainandincreasetheratiooftheprincipaltothesecondlobeofthecodingsignal,andcandecreasethebiterrorrateandincreasethecommunicationdistance.

  • 标签: 时间反转 水下通讯 声音脉冲 多路效应 自适应调焦
  • 简介:InthispaertheinequalityofLemma1of[1]isextended.BymeansofourinequalityandthemethodofLyapunovfunctionwestudythestabilityoftwokindsoflargeseatedifferentialsystemswithtimelagandthestabilityofahigher-orderdifferentialequationwithtimelag.Thesufficientconditionsforthestability(S.),theasymptoticstability(A.S.),theuniformlyasymptoticstability(U.A.S)andtheexponentialasymptoticstability(E.A.S.)ofthezerosolutionsofthesystermsareobtainedrespectively.

  • 标签: 时滞偏微分 渐进稳定性 不平衡性 连续矩阵