VideoStreamingAPI
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4AlwaysMulticast

Alwaysmulticastmeansstartingamulticaststreamandlettingitruncontinuously.Enablingalwaysmulticastreducesthelatency
whenconnectingtoanAxisproduct.ThealwaysmulticaststreamsenabledontheAxisproductarepresentedbyaSessionDescription
Protocol(SDP).Usingthisinformationtheclientcanchoosetoconnecttotheservice.

4.1Prerequisites

4.1.1Identication

Property:Properties.API.HTTP.Version=3
Firmware:5.40andlater.

4.2SDP

Theclientmakesarequestaccordingtotheexamplebelow.Thecameraparameterspeciesthedesiredvideosourceonthe
Axisproduct.
TomakeaSDPrequestitisrequiredthatNetwork.RTP.R0.AlwaysMulticastVideo=yes.

4.2.1RequestSDPURL

Request:
http://myserver/axis-cgi/alwaysmulti.sdp?camera=1

4.2.2ResponseSDPURL

TheAxisproductrespondstherequestwithaSDP.TheSDPisprotectedbytheHTTPauthenticationoftheAxisproductandrequires
adminaccesscontrol.
Response:
v=0
o=-12844643630929041284464363092904INIP4axis
s=Multicastpresentation
e=NONE
t=00
a=range:npt=0.000000-
m=video50000RTP/AVP96
c=INIP4239.225.149.138/0
b=AS:50000
a=framerate:25.0
a=transform:1,0,0;0,1,0;0,0,1
a=rtpmap:96H264/90000
a=fmtp:96packetization-mode=1;profile-level-id=420029;
sprop-parameter-sets=Z0IAKeKQFgJNgScFAQXh4kRU,aM48gA==
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