Measuring Quality of Experience for MPEG-21-based Cross-Layer Multimedia Content Adaptation

MeasuringQualityofExperienceforMPEG‐21‐basedCross‐LayerMul>mediaContentAdapta>on

Chris&anTimmerer

KlagenfurtUniversity(UNIKLU)FacultyofTechnicalSciences(TEWI)DepartmentofInforma&onTechnology(ITEC)Mul&mediaCommunica&on(MMC)

hBp://research.>mmerer.comhBp://blog.>mmerer.commailto:chris>an.>[email protected]‐klu.ac.at

Co‐Authors:Chris>anTimmerer(UniversityofKlagenfurt,Austria),VíctorH.Ortega(Tecsidel,Spain),JoséM.González,andAlbertoLeón(Telefonica,Spain)

Acknowledgment:ThisworkissupportedbytheEuropeanCommissioninthecontextoftheENTHRONEproject(IST‐1‐507637).Furtherinforma>onisavailableathBp://www.ist‐enthrone.org.

Outline

•  OverviewandContext

•  ProbingQualityofService/Experience

•  MPEG‐21Overview(DigitalItemAdapta>on)

•  AnInteroperableQoSModelforVideoTransmissionExploi>ngCross‐LayerInterac>ons

•  Conclusions2008/04/03 2Chris>anTimmerer‐UNIKLU‐WISe'08,Doha,Qatar

OverviewandContext

2008/04/03 Chris>anTimmerer‐UNIKLU‐WISe'08,Doha,Qatar 3

RichMul&mediaContent

DiverseSetofTerminalDevices,UserPreferences

HeterogeneousNetworks,DynamicCondi&ons

ContentAdapta&onforUniversalAccess

Growingmismatch⇓

Needforscalablecontent,descrip&ons,nego&a&on,adapta&on

OverviewandContext


RichMul&mediaContent

DiverseSetofTerminalDevices,UserPreferences

HeterogeneousNetworks,DynamicCondi&ons

ContentAdapta&onforUniversalAccess

Growingmismatch⇓

Needforscalablecontent,descrip&ons,nego&a&on,adapta&on

...but,where‘sthe(end)user?

OverviewandContext(cont‘d)


OverviewandContext(cont‘d)


End‐to‐EndQoSManagement+Interoperability

Cross‐LayerStyle

ProbingQualityofService/Experience

Audio•  ETSI/ITU‐T‘sE‐model:"Psychologicalfactorsonthepsychological

scaleareaddi>ve"•  Factors:packetloss,delay,equipmentimpairment,packetloss

robustnessfactors(dependsoncodec)

Video•  Profiles/Levelswithdiff.resolu>ons,framespersecond,bitrates,

etc.•  PeakSignaltoNoiseRa>o(PSNR),MeanOpinionSquare(MOS),

VideoQualityMetric(VQM)•  Variousmodelsexist,e.g.,perceptualimpressionofpacketloss,

frameratevaria>onandsync.w/audio

needforinteroperablesolu&ons2008/04/03 Chris>anTimmerer‐UNIKLU‐WISe'08,Doha,Qatar 7

TheMPEG‐21Mul>mediaFramework

MPEG‐21Vision•  ...toenabletransparentandaugmenteduseofmul>mediaresources

acrossawiderangeofnetworks,devices,userpreferences,andcommuni>es,notablyfortrading(ofbits)

What?–DigitalItems(DIs)•  ADigitalItem(DI)isastructureddigitalobjectwithastandard

representa>on,iden>fica>on,andmetadatawithintheMPEG‐21framework

•  DigitalItemsare“thecontent”Who?–Users•  AUserisanyen>tythatinteractsintheMPEG‐21environmentormakes

useofaDigitalItem•  Userswillassumerightsandresponsibili>esaccordingtotheirinterac>on

withotherUsers•  Allpar>esthathavearequirementwithinMPEG‐21tointeractare

categorizedequallyasUsers


Adapta&on

MPEG‐21Organisa>on–Parts

2008/04/03 Chris>anTimmerer‐UNIKLU‐WISe'08,Doha,Qatar

Vision,Declara&on,andIden&fica&on

DigitalRights

Management

Adapta&on Processing Systems Misc

Pt.4:IPMPComponents

Pt.5:RightsExpressionLang

Pt.6:RightsDataDic>onary

Pt.7:DigitalItemAdapta>on

Pt.10:DigitalItemProcessing

Amd.1:Convers.AndPermissions

Amd.2:DynamicandDistributedAdapta>on

Pt.1:Vision,TechnologiesandStrategy

Pt.2:DigitalItemDeclara>on

Pt.3:DigitalItemIden>fica>on

Pt.9:FileFormat

Pt.16:BinaryFormat

Pt.18:DigitalItemStreaming

Pt.8:ReferenceSosware

Pt.11:PersistentAssocia>on

Pt.12:TestBed

Pt.14:Conform.

Pt.15:EventRepor>ng

Pt.17:FragmentIdenfica>on

Amd.1:Add‘lC++bindings

Amd.1:DIIrela>onshiptypes

9

MPEG‐21DigitalItemAdapta>on•  Sa>sfytransmission,storageandconsump>onconstraintsaswellasQoS

management•  Enabletransparentaccessto(distributed)advancedmul>mediacontent

byshieldingusersfromnetworkandterminalinstalla>onissues

RelevantTools(amongother)•  UsageEnvironmentDescrip>on(UED)

–  network,terminal,user,naturalenvironment

•  UniversalConstraintsDescrip>on(UCD)–  limita>on,op>miza>on

•  Adapta>onQoS–  rela>onshipbetweenconstraints(i.e.,theUED/UCD),feasibleadapta>on

opera>ons(e.g.,transcoding,scaling,etc.)sa>sfyingtheseconstraints,andassociatedu>li>es(i.e.,quali>es/PSNR).


AnInteroperableQoSModelforVideoTransmissionExploi>ngCross‐LayerInterac>ons•  AVCtestcontent:framerate[6.25,25]fps;bitrate[150,1500]kbps;packetloss[0,10]%

•  Publicsurvey(acrossEU)–boBom‐upapproach

ImpactofPacketLoss•  Bernoullimodel=>packetlossrandomlydistributedoveruniformprobabilitydensityfunc>on(allpacketshavesameprobabilitytobedropped)

•  Realworld:packetloss==burstsofrandomlength

calculatethequalityinshortintervals(packetlossdensitydistribu>oncanbeconsidereduniformevenifweareinsideaburst)


(1)

AnInteroperableQoSModelforVideoTransmissionExploi>ngCross‐LayerInterac>ons•  AVCtestcontent:framerate[6.25,25]fps;bitrate[150,1500]kbps;packetloss[0,10]%

•  Publicsurvey(acrossEU)–boBom‐upapproach

ImpactofPacketLoss•  Bernoullimodel=>packetlossrandomlydistributedoveruniformprobabilitydensityfunc>on(allpacketshavesameprobabilitytobedropped)

•  Realworld:packetloss==burstsofrandomlength

calculatethequalityinshortintervals(packetlossdensitydistribu>oncanbeconsidereduniformevenifweareinsideaburst)


(1)

AnInteroperableQoSModelforVideoTransmissionExploi>ngCross‐LayerInterac>ons(cont’d)

ImpactofBandwidth

•  Differentbandwidthcurvesstudied rela>onshipbetweenbitrateandthepacketloss

ImpactofFrameRate

•  Classifica>onaccordingtotemporalnature+actualaudio‐visualcontent:[1..7](7isthebest)

ExtrapolatedforVoDszenarionwithhightemporalnature


(2)

(3)


ImpactofBandwidth

•  Differentbandwidthcurvesstudied rela>onshipbetweenbitrateandthepacketloss

ImpactofFrameRate

•  Classifica>onaccordingtotemporalnature+actualaudio‐visualcontent:[1..7](7isthebest)

ExtrapolatedforVoDszenarionwithhightemporalnature


(2)

(3)


ProposedModel

addinteroperabilitysupport


(4)

AddingMPEG‐21SupportEnablingInteroperableCross‐LayerInterac>ons


AdaptationQoS Stack Function for MOS (aqos.xml):  <Module xsi:type="StackFunctionType" iOPinRef="MOS"> <StackFunction> <Argument xsi:type="InternalIOPinRefType" iOPinRef="F_FRAMERATE"/> <Argument xsi:type="InternalIOPinRefType" iOPinRef="F_PACKETLOSS"/>  <Operation operator=":SFO:18"/> </StackFunction> </Module> UCD maximizing the MOS (ucd_provider.xml): <OptimizationConstraint optimize="maximize"> <Argument xsi:type="ExternalIOPinRefType" iOPinRef="aqos.xml#MOS"/> </OptimizationConstraint> UED (ued.xml): <Network xsi:type="NetworkType"> <NetworkCharacteristic xsi:type="NetworkConditionType"> <AvailableBandwidth average="1500000"/> <Error packetLossRate="0.03"/> </NetworkCharacteristic> </Network> UCD for probe constraints (ucd_probe.xml):  <LimitConstraint> <Argument xsi:type="SemanticalRefType" semantics=":AQoS:6.6.5.8"/> <Argument xsi:type="ConstantDataType"> <Constant xsi:type="FloatType"> <Value>0.1</Value> </Constant> </Argument> <Operation operator=":SFO:38"/> </LimitConstraint>

•  Describefunc>onaldependenciesof(4)–  MPEG‐21DIAAdapta>onQoS'stack

func>ons–  Rangeofpossiblecontentframerateand

bit‐ratecombina>onssolu>onspace

•  Usageenvironment:networkcondi>ons(bandwidth,packetloss)–  MPEG‐21DIAUsageEnvironmentDescrip>on

•  Constraintsoftheprobe(pl,br,fps)+objec>vefunc>on,i.e.,maximizetheMOS–  MPEG‐21DIAUniversalConstraintsDescrip>on

ConclusionsandFutureWork

•  QoS/QoE:guaranteethequalityofmul>mediatrafficexperimentedbytheuser

translatenetworkissuesintouserperceivedquality

•  Newmodelforevalua>ngthequalityofvideostreamsproposed–extractedfromRTPtraffic

•  InteroperabilityacrosslayersthroughMPEG‐21

•  @TODOevalua>oninlarge‐scalepilotsfeaturinginter‐connectedtest‐bedsacrossEuropeFP6‐IST‐ENTHRONE