Don't use old RTCP SR reports for remote clock estimation
At the beginning of the call, when rtt is not yet estimated, SR packets
are not used for estimation. Yet, it may happen that on some non-SR
RTCP packet RTT would become available. At that time an old SR will be
used for remote clock estimation. This will lead to remote clock offset
to the past too much.
Bug: webrtc:8468
Change-Id: I1bdbd56a7bab1c28e73987e5fb307f8e7382b045
Reviewed-on: https://webrtc-review.googlesource.com/16840
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20528}diff --git a/video/rtp_video_stream_receiver.cc b/video/rtp_video_stream_receiver.cc
index aecdfe3..5778682 100644
--- a/video/rtp_video_stream_receiver.cc
+++ b/video/rtp_video_stream_receiver.cc
@@ -533,12 +533,20 @@
uint32_t ntp_secs = 0;
uint32_t ntp_frac = 0;
uint32_t rtp_timestamp = 0;
- if (rtp_rtcp_->RemoteNTP(&ntp_secs, &ntp_frac, nullptr, nullptr,
- &rtp_timestamp) != 0) {
+ uint32_t recieved_ntp_secs = 0;
+ uint32_t recieved_ntp_frac = 0;
+ if (rtp_rtcp_->RemoteNTP(&ntp_secs, &ntp_frac, &recieved_ntp_secs,
+ &recieved_ntp_frac, &rtp_timestamp) != 0) {
// Waiting for RTCP.
return true;
}
- ntp_estimator_.UpdateRtcpTimestamp(rtt, ntp_secs, ntp_frac, rtp_timestamp);
+ NtpTime recieved_ntp(recieved_ntp_secs, recieved_ntp_frac);
+ int64_t time_since_recieved =
+ clock_->CurrentNtpInMilliseconds() - recieved_ntp.ToMs();
+ // Don't use old SRs to estimate time.
+ if (time_since_recieved <= 1) {
+ ntp_estimator_.UpdateRtcpTimestamp(rtt, ntp_secs, ntp_frac, rtp_timestamp);
+ }
return true;
}