Axis P7210 - Video and Audio (Image Settings); Pixel Counter and Image Settings; H.264 and MJPEG Details

AXISP7210VideoEncoder
VideoandAudio
PixelCounter
Thepixelcountershowsthenumberofpixelsinanareaoftheimage.Thepixelcounterisusefulinsituationswherethereisa
requirementthattheimageisacertainsize,forexampleinfacerecognition.
Thepixelcountercanbeaccessedfrom:
•Video&Audio>VideoStream.UnderPreview,clickOpenandselecttheShowpixelcounteroptiontoenablethe
rectangleintheimage.Usethemousetomoveandresizetherectangle,orenterthenumberofpixelsintheWidth
andHeighteldsandclickApply.
•TheLiveViewpageinInternetExplorerinWindows.Right-clickintheimageandselectPixelcounter.Usethemouse
tomoveandresizetherectangle.
Image
ThedefaultimagesettingscanbeconguredunderVideo&Audio>VideoStream.SelecttheImagetab.
Thefollowingsettingsareavailable:
•Resolution.Selectthedefaultresolution.
•Compression.Thecompressionlevelaffectstheimagequality,bandwidthandlesizeofsavedimages;thelowerthe
compression,thehighertheimagequalitywithhigherbandwidthrequirementsandlargerlesizes.
•Rotateimage.Ifrequired,theimagecanberotated.
•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.
TheAxisproductsupportstwoH.264proles.TheMainproleprovideshighercompressionthantheBaselineprolewiththesame
videoquality,butrequiresmoreprocessingpowertodecode.
ThebitratecanbesetasVariableBitRate(VBR)orConstantBitRate(CBR).VBRadjuststhebitrateaccordingtotheimage
complexity,usingupmorebandwidthforincreasedactivityintheimage,andlessforlowerimageactivity.CBRallowsyoutoseta
xedTargetbitratethatconsumesapredictableamountofbandwidth.Asthebitratewouldusuallyneedtoincreaseforincreased
imageactivity,butinthiscasecannot,framerateandimagequalityareaffectednegatively.Topartlycompensateforthis,itis
possibletoprioritizeeitherframerateorimagequality.Notsettingaprioritymeansthatframerateandimagequalityareequally
affected.Youmustsaveyoursettingsbeforetheycantakeeffect.
Thecurrentbitratecanbesettoappearastextoverlay.Todothis,selecttheIncludetextcheckboxoptionunderOverlay
Settingsandenterthemodier#bintheeld.
MJPEG
Sometimestheimagesizeislargeduetolowlightorcomplexscenery.Adjustingthemaximumframesizehelpstocontrolthe
bandwidthandstorageusedbytheMotionJPEGvideostreaminthesesituations.SettingtheframesizetotheDefaultsetting
providesconsistentlygoodimagequalityattheexpenseofincreasedbandwidthandstorageusageinlowlight.Limitingtheframe
18