Axis 0673-001 ~ EOL Axis A8004-VE User Manual

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AXISA8004-VENetworkVideoDoorStation

VideoandAudio

•Maximumframerate.Toavoidbandwidthproblems,theframerateallowedtoeachviewercanbeLimitedtoaxed

amount.Alternatively,theframeratecanbesetasUnlimited,whichmeanstheAxisproductalwaysdeliversthehighest

frameratepossibleunderthecurrentconditions.

•Overlaysettings.SeeOverlayonpage24.

ClickSavetoapplythenewsettings.

H.264

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

AnH.264videostreamconsistsofdifferenttypesofframessuchasI-framesandP-frames.AnI-frameisacompleteimagewhereas

P-framesonlycontainthedifferencesfrompreviousframes.

TheH.264streamsettingscanbeconguredfromtheVideo&Audio>VideoStreampage.SelecttheH.264tab.Thesettings

denedinthispagewillapplytoallH.264streamsthatdonotuseastreamprole.

TheGOVlengthisthenumberofframesbetweentwoconsecutiveI-frames.IncreasingtheGOVlengthmaysaveconsiderablyon

bandwidthrequirementsinsomecases,butmayalsohaveanadverseaffectonimagequality.

TheAxisproductsupportsthefollowingH.264prole(s):

•Baseline.TheBaselineproleisrecommendedforclientsthatdon’tsupportCABACentropycoding.

•Main.TheMainproleprovideshighercompressionwithmaintainedvideoqualitycomparedtotheBaselineprolebut

requiresmoreprocessingpowertodecode.

ThebitratecanbesetasVariablebitrate(VBR)orMaximumbitrate(MBR).VBRadjuststhebitrateaccordingtotheimage

complexity,usingupmorebandwidthforincreasedactivityintheimage,andlessforlowerimageactivity.Whentheactivityin

thesceneincreases,thebitratewouldusuallyincreaseaswell.Ifthereisasurplusinbandwidth,thismaynotbeanissueand

selectingVariablebitrate(VBR)willbesufcient.Butifbandwidthislimited,itisrecommendedtocontrolthebitratebyselecting

Maximumbitrate(MBR).Whentheactivityinthesceneincreases,VBRadjuststhebitrateaccordingtothecomplexity,usingup

morebandwidthforincreasedactivityinthescene,andlessforlowersceneactivity.MBRallowsyoutosetatargetbitratethat

limitsthebandwidthconsumption.

TheMBRtargetbitrateworksliketheceilingofatent.Itlimitsthebitrate,whilemaintainingsomeexibility.Thebitrate

maybounceupanddownwithinthesettargetbutwhenitnearsthesettargetvalue,thelimitationkicksin.However,because

MBRwillalwaysprioritizeacontinuousvideostream,itallowstemporaryovershootsfromthetargetbitrate.Becausesettinga

targetvaluepreventsthebitratefromincreasing,framerateandimagequalityareaffectednegatively.Topartlycompensatefor

this,selectwhichvariableshallbeprioritized,framerateorimagequality.Notsettingaprioritymeansthatframerateand

imagequalityareequallyaffected.

Thecurrentbitratecanbesettoappearastextoverlay.UnderOverlaySettings,selectIncludetextandenterthemodier

#bintheeld.

Toapplythesettings,clickSave.

MJPEG

Sometimestheimagesizeislargeduetolowlightorcomplexscenery.Adjustingthemaximumframesizehelpstocontrolthe

bandwidthandstorageusedbytheMotionJPEGvideostreaminthesesituations.SettingtheframesizetotheDefaultsetting

providesconsistentlygoodimagequalityattheexpenseofincreasedbandwidthandstorageusageinlowlight.Limitingtheframe

sizeoptimizesbandwidthandstorageusage,butmaygivepoorimagequality.Topreventincreasedbandwidthandstorageusage,

themaximumframesizeshouldbesettoanoptimalvalue.

StreamProles

Astreamproleisasetofpredenedstreamsettingsincludingresolution,compression,framerateandoverlaysettings.Stream

prolescanbeused:

•Whensettinguprecordingusingactionrules.SeeEventsonpage46.

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Axis 0673-001 ~ EOL A8004-VE Network Video Door Station 0673-001

Axis A8004-VE User Manual - Page 21