简介:Thispaperpresentsahumandetectionsysteminavision-basedhospitalsurveillanceenvironment.Thesystemiscomposedofthreesubsystems,i.e.backgroundsegmentationsubsystem(BSS),humanfeatureextractionsubsystem(HFES),andhumanrecognitionsubsystem(HRS).ThecodebookbackgroundmodelisappliedintheBSS,thehistogramoforientedgradients(HOG)featuresareusedintheHFES,andthesupportvectormachine(SVM)classificationisemployedintheHRS.Bymeansoftheintegrationofthesesubsystems,thehumandetectioninavision-basedhospitalsurveillanceenvironmentisperformed.Experimentalresultsshowthattheproposedsystemcaneffectivelydetectmostofthepeopleinhospitalsurveillancevideosequences.
简介:Traditionalbackgroundmodelmethodsoftenrequirecomplicatedcomputations,andaresensitivetoilluminationandshadow.Inthispaper,weproposeablock-basedbackgroundmodelingmethod,anduseourproposedmethodtocombinecolorandtexturecharacteristics.Suppressionandrelaxationarethetwokeystrategiestoresistilluminationchangesandshadowdisturbance.Theproposedmethodisquiteefficientandiscapableofresistingilluminationchanges.Experimentalresultsshowthatourmethodissuitableforreal-wordscenesandreal-timeapplications.
简介:Super-Resolution(SR)techniquemeanstoreconstructHigh-Resolution(HR)imagesfromasequenceofLow-Resolution(LR)observations,whichhasbeenagreatfocusforcompressedvideo.BasedonthetheoryofProjectionOntoConvexSet(POCS),thispaperconstructsQuantizationConstraintSet(QCS)usingthequantizationinformationextractedfromthevideobitstream.BycombiningthestatisticalpropertiesofimageandtheHumanVisualSystem(HVS),anovelAdaptiveQuantizationConstraintSet(AQCS)isproposed.SimulationresultsshowthatAQCS-basedSRal-gorithmconvergesatafastrateandobtainsbetterperformanceinbothobjectiveandsubjectivequality,whichisapplicableforcompressedvideo.
简介:ThisletterproposesaratecontrolalgorithmforH.264videoencoder,whichisbasedonblockactivityandbufferstate.ExperimentalresultsindicatethatithasanexcellentperformancebyprovidingmuchaccuratebitrateandbettercodingefficiencycomparedwithH.264.ThecomputationalcomplexityofthealgorithmisreducedbyadoptinganovelblockactivitydescriptionmethodusingtheSumofAbsoluteDifference(SAD)of16×16mode,anditsrobustnessisenhancedbyintroducingafeedbackcircuitatframelayer.
简介:Thisletterproposesanefficientwavelet-basedFineGranularityScalable(FGS)codingscheme,wherethebaselayerisencodedwithanewlydesignedwavelet-basedcoder,andtheenhancementlayerisencodedwithProgressiveFineGranularityScalable(PFGS)coding.Thisalgorithminvolvesmulti-framemotioncompensation,rate-distortionoptimizingstrategywithLagrangiancostfunctionandcontext-basedadaptivearithmeticcoding.Inordertoimproveefficiencyoftheenhancementlayercoding,animprovedmotionestimationschemethatusesbothinformationfromthebaselayerandtheenhancementlayerisalsoproposedinthisletter.Thewavelet-basedcodersignificantlyimprovesthecodingefficiencyofthebaselayercomparedwithMPEG-4ASP(AdvancedSimpleProfile)andH.26LTML9.ThePFGScodingisasignificantimprovementoverMPEG-4FGScodingattheenhancementlayer.Experimentsshowthatsinglelayercodingefficiencygainoftheproposedschemeisabout2.0-3.0dBand0.3-1.0dBhigherthanthatofMPEG-4ASPandH.26LTML9,respectively.Theoverallcodingefficiencygainoftheproposedschemeisabout4.0-5.0dBhigherthanthatofMPEG-4FGS.
简介:PresentedisaschemeofanembeddedvideoremotemonitoringsystembasedonTMS320DM642.UsingDM642asthedataprocessingcore,theremotemonitoringsystemiscomposedofvideoacquisitionmodule,videoprocessingmoduleandcommunicationmodule,whichgivesanimplementationofclass/minidrivermoduleinDSP/BIOSintegrateddevelopingenvironmentandalsoacommontaskmoduleinapplicationlayerisachieved.Thesystemrealizestheentirefunctionsoftheanalogvideosignalacquisition,H.264videocodingandInternettransmission.Itprovidesthegeneralconnectionforthefuturedevelopmentandhasgoodflexibilityandextendibility.Thesystemusesamodulardesignandoveralldevelopmentofprogrammingmethodstoimprovetheefficiencyofsystemdevelopment.
简介:Inthispaperweproposeathreedimensionalmultiplierlessdiscretecosinetransform(DCT)withliftingschemecalled3D-binDCT.Basedon3D-binDCT,anovelvideocodingalgorithmwithoutmotionestimation/compensationisproposed.Itusesthe3D-binDCTtoexploitspatialortemporalredundancy.ThecomputationofbinDCTonlyneedsshiftandadditionoperations,thusthecomputationalcomplexityisminimized.DCcoefficientprediction,modifiedscanmodeandarithmeticcodingtechniquesarealsoadopted.Extensivesimulationresultsshowthattheproposedcodingschemeprovideshighercodingefficiencyandimprovesvisualquality,anditiseasytoberealizedbysoftwareandhardware.
简介:Movingobjectextractionandclassificationareimportantproblemsinautomatedvideosurveillancesystems.Abackgroundmodelbasedonregionsegmentationisproposed.AnadaptivesingleGaussianbackgroundmodelisusedinthestableregionwithgradualchanges,andanonparametricmodelisusedinthevariableregionwithjumpingchanges.Ageneralizedagglomerativeschemeisusedtomergethepixelsinthevariableregionandfillinthesmallinterspaces.Atwo-thresholdsequentialalgorithmicschemeisusedtogroupthebackgroundsamplesofthevariableregionintodistinctGaussiandistributionstoacceleratethekerneldensitycomputationspeedofthenonparametricmodel.Inthefeature-basedobjectclassificationphase,thesurveillancesceneisfirstpartitionedaccordingtotheroadboundariesofdifferenttrafficdirectionsandthenre-segmentedaccordingtotheirscenelocalities.Themethodimprovesthediscriminabilityofthefeaturesineachpartition.AdaBoostmethodisappliedtoevaluatetherelativeimportanceofthefeaturesineachpartitionrespectivelyanddistinguishwhetheranobjectisavehicle,asinglehuman,ahumangroup,orabike.Experimentalresultsshowthattheproposedmethodachieveshigherperformanceincomparisonwiththeexistingmethod.
简介:Toaimathighercodingefficiencyformultiviewvideocoding,themultiviewvideowithamodifiedhighefficiencyvideocoding(MV-HEVC)codecisproposedtoencodethedependentviews.However,thecomputationalcomplexityofMV-HEVCencoderisalsoincreasedsignificantlysinceMV-HEVCinheritsallcomputationalcomplexityofHEVC.ThispaperpresentsanefficientalgorithmforreducingthehighcomputationalcomplexityofMV-HEVCbyfastdecidingthecodingunitduringtheencodingprocess.Inourproposal,thedepthinformationofthelargestcodingunits(LCUs)fromindependentviewandneighboringLCUsisanalyzedfirst.Afterwards,theanalyzedresultsareusedtoearlydeterminethedepthfordependentviewandthusachievecomputationalcomplexityreduction.Furthermore,apredictionunit(PU)decisionstrategyisalsoproposedtomaintainthevideoquality.Experimentalresultsdemonstratethatouralgorithmcanachieve57%timesavingonaverage,whilemaintaininggoodvideoqualityandbit-rateperformancecomparedwithHTM8.0.
简介:Ahybridpilotsassistedchannelestimationalgorithmformultipleinputmultipleoutput(MIMO)orthogonalfrequencydivisionmultiplexing(OFDM)systemsunderlowsignal-to-noiseratio(SNR)andarbitraryDopplerspreadscenariosisproposed.Motivatedbythedissatisfactoryperformanceoftheoptimalpilots(OPs)designedunderstaticchannelsovermultipleOFDMsymbolsimposedbyfastfadingchannels,theproposedschemefirstassumesthatthevirtualpilottonessuperimposedatdatalocationsoverspecificsubcarriersaretransmittedfromallantennas,thenthevirtualreceivedpilotsignalsatthecorrespondinglocationscanbeobtainedbymakingfulluseofthetimeandfrequencydomaincorrelationsofthefrequencyresponsesofthetimevaryingdispersivefadingchannelsandthereceivedsignalsatpilotsubcarriers,finallythechannelparametersarederivedfromthecombinationoftherealandvirtualreceivedpilotsignalsoveroneOFDMsymbolbasedonleastsquare(LS)criterion.SimulationresultsillustratethattheproposedmethodisinsensitivetoDopplerspreadandcaneffectivelyamelioratethemeansquareerror(MSE)floorinherenttothepreviousmethod,meanwhileitsperformanceoutmatchesthatofOPsatlowSNRregionunderstaticchannels.
简介:Videoobjectextractionisakeytechnologyincontent-basedvideocoding.AnovelvideoobjectextractingalgorithmbytwoDimensional(2-D)mesh-basedmotionanalysisisproposedinthispaper.Firstly,a2-Dmeshfittingtheoriginalframeimageisobtainedviafeaturedetectionalgorithm.Then,higherorderstatisticsmotionanalysisisappliedonthe2-Dmeshrepresentationtogetaninitialmotiondetectionmask.Afterpost-processing,thefinalsegmentingmaskisquicklyobtained.Andhencethevideoobjectiseffectivelyextracted.Experimentalresultsshowthattheproposedalgorithmcombinesthemeritsofmesh-basedsegmentingalgorithmsandpixel-basedsegmentingalgorithms,andherebyachievessatisfactorysubjectiveandobjectiveperformancewhiledramaticallyincreasingthesegmentingspeed.
简介:InordertoimprovethevideotransmissionperformanceinMultiple-InputMultiple-OutputOrthogonalFrequencyDivisionMultiplexing(MIMO-OFDM)system,anewscheme,whichintegratesMultipleDescriptionCoding(MDC),LowDensityParityCheck(LDPC)codingandhybridspacetimecoding,isproposedinthisletter.Inparticular,ahybridspacetimecodingalgorithmiscombinedwithLDPCcodestoperformUnequalErrorProtection(UEP)ofMDCencodedvideostreams.ComparingwiththeUEPtransmissionwithonlyLDPCcodes,theproposedschemeachievesmorethan1dBgainintermsofSignaltoNoiseRatio(SNR)whenthePeakSignaltoNoiseRatio(PSNR)ofreconstructedvideoisabove30dB.
简介:Thewirelesssensornetwork(WSN)consistsofsensornodesthatinteractwitheachothertocollectivelymonitorenvironmentalorphysicalconditionsatdifferentlocationsfortheintendedusers.Oneofitspotentialdeploymentsisintheformofsmarthomeandambientassistedliving(SHAAL)tomeasurepatientsorelderlyphysiologicalsignals,controlhomeappliances,andmonitorhome.ThispaperfocusesonthedevelopmentofawirelesssensornodeplatformforSHAALapplicationoverWSNwhichcomplieswiththeIEEE802.15.4standardandoperatesin2.4GHzISM(industrial,scientific,andmedical)band.TheinitialstageofSHAALapplicationdevelopmentisthedesignofthewirelesssensornodenamedTelGmote.ThemainfeaturesofTelGmotecontributingtothegreencommunicationsincludelowpowerconsumption,wearable,flexible,user-friendly,andsmallsizes.Itisthenembeddedwithaself-builtoperatingsystemnamedWiseOStosupportcustomizedoperation.Thenodecanachieveapacketreceptionrate(PRR)above80%foradistanceofupto8m.ThedesignedTelGmoteisalsocomparablewiththeexistingwirelesssensornodesavailableinthemarket.
简介:Thepaperfirstdiscussesshortcomingsofclassicaladjacent-framedifference.Secondly,basedontheimageenergyandhighorderstatistic(HOS)theory,backgroundreconstructionconstraintsaresetup.Underthehelpofblock-processingtechnology,backgroundisreconstructedquickly.Finally,backgrounddifferenceisusedtodetectmotionregionsinsteadofadjacentframedifference.TheDSPbasedplatformtestsindicatethebackgroundcanberecoveredlosslesslyinaboutonesecond,andmovingregionsarenotinfluencedbymovingtargetspeeds.Thealgorithmhasimportantusagebothintheoryandapplications.