zqz/platform-external-webrtc
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

In RTP to NTP estimator use linear regression instead of ad hoc filter

Browse Source 
Make averaging test in NtpEstimator less sensitive.

TESTED=Locally patched into chrome and tested on 1st party software and in video_loopback. All produced parameters looked reasonable.

Bug: webrtc:9698
Change-Id: Idc5e80c657ef190dc95da1e27d1288ff9eddd139
Reviewed-on: https://webrtc-review.googlesource.com/c/110500
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25603}
This commit is contained in:
Ilya Nikolaevskiy
2018-11-12 15:03:51 +01:00
committed by Commit Bot
parent c42d62495c
commit f1cc3a26cd
5 changed files with 135 additions and 89 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
system_wrappers/include/rtp_to_ntp_estimator.h
View File

@ -42,23 +42,13 @@ class RtpToNtpEstimator {
// Estimated parameters from RTP and NTP timestamp pairs in |measurements_|.
struct Parameters {
// Implicit conversion from int because MovingMedianFilter returns 0
// internally if no samples are present. However, it should never happen as
// we don't ask smoothing_filter_ to return anything if there were no
// samples.
Parameters(const int& value) { // NOLINT
RTC_NOTREACHED();
}
Parameters() : frequency_khz(0.0), offset_ms(0.0) {}
Parameters(double frequency_khz, double offset_ms)
: frequency_khz(frequency_khz), offset_ms(offset_ms) {}
double frequency_khz;
double offset_ms;
// Needed to make it work inside MovingMedianFilter
bool operator<(const Parameters& other) const;
bool operator==(const Parameters& other) const;
bool operator<=(const Parameters& other) const;
bool operator!=(const Parameters& other) const;
};
// Updates measurements with RTP/NTP timestamp pair from a RTCP sender report.
@ -70,7 +60,7 @@ class RtpToNtpEstimator {
// Converts an RTP timestamp to the NTP domain in milliseconds.
// Returns true on success, false otherwise.
bool Estimate(int64_t rtp_timestamp, int64_t* rtp_timestamp_ms) const;
bool Estimate(int64_t rtp_timestamp, int64_t* ntp_timestamp_ms) const;
// Returns estimated rtp to ntp linear transform parameters.
const absl::optional<Parameters> params() const;
@ -82,8 +72,7 @@ class RtpToNtpEstimator {
int consecutive_invalid_samples_;
std::list<RtcpMeasurement> measurements_;
MovingMedianFilter<Parameters> smoothing_filter_;
bool params_calculated_;
absl::optional<Parameters> params_;
mutable TimestampUnwrapper unwrapper_;
};
} // namespace webrtc