Axis 0871-001~EOL Axis A8105-E User Manual

Loading ...

AXISA8105-ENetworkVideoDoorStation

VideoandAudio

•Rotateimage.Ifrequired,theimagecanberotated.

•Maximumframerate.Toavoidbandwidthproblems,theframerateallowedtoeachviewercanbeLimitedtoaxed

amount.Alternatively,theframeratecanbesetasUnlimited,whichmeanstheAxisproductalwaysdeliversthehighest

frameratepossibleunderthecurrentconditions.

•Overlaysettings.SeeAboutoverlaytextonpage28.

ClickSavetoapplythenewsettings.

AboutH.264

H.264,alsoknownasMPEG-4Part10/AVC,isavideocompressionstandardthatprovideshighqualityvideostreamsatlowbitrates.

AnH.264videostreamconsistsofdifferenttypesofframessuchasI-framesandP-frames.AnI-frameisacompleteimage,whereas

P-framesonlycontainthedifferencesfrompreviousframes.

AboutGOPlength

AGroupofPictures(GOP)containsoneI-framefollowedbyanumberofP-frames.TheGOPlengthisthenumberofframes

betweentwoI-frames.

IfyousettheGOPlengthandtheframerateequallyyouwillgetoneGOPpersecond.IfyouchangetheGOPlengthtoahigher

valueyouwillgetmoresmallsizedP-framesandlessbigsizedI-frameswhilekeepingthesameframerate.Inotherwords,ahigh

GOP-lengthvaluesavesbandwidth,butthevideoqualitymaydecrease.AlowGOP-lengthvalueincreasesthevideoquality

butneedsmorebandwidth.

AboutH.264proles

TheAxisproductsupportsthefollowingH.264prole(s):

•Baseline:UsetheBaselineproleiftheclientdoesnotsupportCABACentropycoding.

•Main:TheMainproleusesCABACandprovidesabettercompressionwithmaintainedvideoquality.Itrequiresalarger

amountofprocessingpowertodecodethantheBaselineprole.

•High:TheHighproleprovidesahighercompressionthanbothMainandBaselineproles,butrequiresmoreprocessing

powertodecode.Highprolesupports8x8blocks,whichreducesthebitratefurthercomparedtotheMainprole.

Aboutbitratecontrol

Bitratecontrolisusefultomakesurethevideostreamingdoesnottakeuptoomuchbandwidth.

Aboutvariablebitrate

Variablebitrate(VBR)adjuststhebitrateaccordingtotheimagecomplexity.Whentheactivityinthesceneincreases,VBRadjusts

thebitrateaccordingtothecomplexity,usingupmorebandwidthforincreasedactivityinthescene,andlessforlowersceneactivity.

Variablebitrateissuitableifthereisasurplusinbandwidth,wheretheincreasedbitratemaynotbeanissue.

Aboutmaximumbitrate

Ifyouhavelimitedbandwidth,werecommendMaximumbitrate(MBR).MBRallowsyoutosetatargetbitratetocontrolthe

bandwidthconsumption.Thetargetvaluelimitsthebitrate,butitmaintainsaexibilitytobeabletoprioritizeacontinuousvideo

stream.Consequently,theframeratemightneedtogodownandtheimagequalitymightdecrease.Topartlycompensateforthis,

youcanselectwhichvariableshallbeprioritized.Notsettingaprioritymeansthatframerateandimagequalityareequallyaffected.

Loading ...

Axis 0871-001~EOL A8105-E Network Video Door Station 0871-001