Axis M1025 - Page 17

AXISM1025NetworkCamera
SettingUptheProduct
Image
ThedefaultimagesettingscanbeconguredunderVideo>VideoStream.SelecttheImagetab.
Thefollowingsettingsareavailable:
•Resolution.Selectthedefaultresolution.
•Compression.Thecompressionlevelaffectstheimagequality,bandwidthandlesizeofsavedimages;thelowerthe
compression,thehighertheimagequalitywithhigherbandwidthrequirementsandlargerlesizes.
•Rotateimage.Ifrequired,theimagecanberotated.
Note
VideostreamsoverHDMIcanonlyberotated180°or0°.
•Mirror.Ifrequired,theimagecanbemirrored.
•Maximumframerate.Toavoidbandwidthproblems,theframerateallowedtoeachviewercanbeLimitedtoaxed
amount.Alternatively,theframeratecanbesetasUnlimited,whichmeanstheAxisproductalwaysdeliversthehighest
frameratepossibleunderthecurrentconditions.
•Overlaysettings.SeeOverlay,onpage20.
ClickSavetoapplythenewsettings.
H.264
H.264,alsoknownasMPEG-4Part10/AVC,isavideocompressionstandardthatprovideshighqualityvideostreamsatlowbitrates.
AnH.264videostreamconsistsofdifferenttypesofframessuchasI-framesandP-frames.AnI-frameisacompleteimagewhereas
P-framesonlycontainthedifferencesfrompreviousframes.
TheGOVlengthisthenumberofframesbetweentwoconsecutiveI-frames.IncreasingtheGOVlengthmaysaveconsiderablyon
bandwidthrequirementsinsomecases,butmayalsohaveanadverseaffectonimagequality.
ThebitratecanbesetasVariablebitrate(VBR)orConstantbitrate(CBR).VBRadjuststhebitrateaccordingtotheimage
complexity,usingupmorebandwidthforincreasedactivityintheimage,andlessforlowerimageactivity.Whentheactivityin
thesceneincreases,thebitratewouldusuallyincreaseaswell.Ifthereisasurplusinbandwidth,thismaynotbeanissueand
selectingVariablebitrate(VBR)willbesufcient.Butifbandwidthislimited,itisrecommendedtocontrolthebitratebyselecting
Constantbitrate(CBR).Whentheactivityinthesceneincreases,VBRadjuststhebitrateaccordingtothecomplexity,usingup
morebandwidthforincreasedactivityinthescene,andlessforlowersceneactivity.CBRallowsyoutosetatargetbitratethat
limitsthebandwidthconsumption.
TheCBRtargetbitrateworksliketheceilingofatent.Itlimitsthebitrate,whilemaintainingsomeexibility.Thebitratemaybounce
upanddownwithinthesettargetbutwhenitnearsthesettargetvalue,thelimitationkicksin.However,becauseCBRwillalways
prioritizeacontinuousvideostream,itallowstemporaryovershootsfromthetargetbitrate.Becausesettingatargetvalueprevents
thebitratefromincreasing,framerateandimagequalityareaffectednegatively.Topartlycompensateforthis,selectwhichvariable
shallbeprioritized,framerateorimagequality.Notsettingaprioritymeansthatframerateandimagequalityareequallyaffected.
Thecurrentbitratecanbesettoappearastextoverlay.UnderOverlaySettings,selectIncludetextandenterthemodier
#bintheeld.
Toapplythesettings,clickSave.
MJPEG
Sometimestheimagesizeislargeduetolowlightorcomplexscenery.Adjustingthemaximumframesizehelpstocontrolthe
bandwidthandstorageusedbytheMotionJPEGvideostreaminthesesituations.SettingtheframesizetotheDefaultsetting
providesconsistentlygoodimagequalityattheexpenseofincreasedbandwidthandstorageusageinlowlight.Limitingtheframe
sizeoptimizesbandwidthandstorageusage,butmaygivepoorimagequality.Topreventincreasedbandwidthandstorageusage,
themaximumframesizeshouldbesettoanoptimalvalue.
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