[webrtc-extensions] senderReceiverTimeOffset should use remoteOutboundRtpStats.roundTripTime (#109)

yuanchao0310 has just created a new issue for https://github.com/w3c/webrtc-extensions:

== senderReceiverTimeOffset should use remoteOutboundRtpStats.roundTripTime   ==
in https://github.com/w3c/webrtc-extensions/blob/main/explainer.md#api-2-sendercapturetimeoffset 
`senderReceiverTimeOffset = remoteOutboundRtpStats.timestamp - (remoteOutboundRtpStats.remoteTimestamp + remoteInboundRtpStats.roundTripTime / 2);
`
if receiver is a recv only endpoint, it cannot get remoteInboundRtpStats.roundTripTime, because  [remoteInboundRtpStats.roundTripTime](https://www.w3.org/TR/webrtc-stats/#dom-rtcremoteinboundrtpstreamstats-roundtriptime) use SR and RR to get rtt time, that means the receiver must send RTP to remote peer.

so need use [remoteOutboundRtpStats.roundTripTime](https://www.w3.org/TR/webrtc-stats/#dom-rtcremoteoutboundrtpstreamstats-roundtriptime), which can be calculated by XR RTCP at receiver side.
after update:

> stats = peerconnection.getStats();
remoteOutboundRtpStats = getRequiredStats(stats, "remote-outbound-rtp");
senderReceiverTimeOffset = remoteOutboundRtpStats.timestamp - (remoteOutboundRtpStats.remoteTimestamp + remoteOutboundRtpStats.roundTripTime / 2)



Please view or discuss this issue at https://github.com/w3c/webrtc-extensions/issues/109 using your GitHub account


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Received on Thursday, 19 May 2022 14:53:46 UTC