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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at */
#ifndef DOM_TelemetryProbesReporter_H_
#define DOM_TelemetryProbesReporter_H_
#include "MediaInfo.h"
#include "mozilla/Maybe.h"
#include "mozilla/AwakeTimeStamp.h"
#include "nsISupportsImpl.h"
namespace mozilla {
class FrameStatistics;
class TelemetryProbesReporterOwner {
virtual Maybe<nsAutoString> GetKeySystem() const = 0;
virtual MediaInfo GetMediaInfo() const = 0;
virtual FrameStatistics* GetFrameStatistics() const = 0;
virtual bool IsEncrypted() const = 0;
virtual void DispatchAsyncTestingEvent(const nsAString& aName) = 0;
* This class is used for collecting and reporting telemetry probes for
* its owner which should inherit from TelemetryProbesReporterOwner. We use it
* for HTMLMediaElement, and each element has one corresponding reporter.
class TelemetryProbesReporter final {
explicit TelemetryProbesReporter(TelemetryProbesReporterOwner* aOwner);
~TelemetryProbesReporter() = default;
enum class Visibility {
void OnPlay(Visibility aVisibility);
void OnPause(Visibility aVisibility);
void OnVisibilityChanged(Visibility aVisibility);
void OnDecodeSuspended();
void OnDecodeResumed();
void OnShutdown();
double GetTotalPlayTimeInSeconds() const;
double GetVisibleVideoPlayTimeInSeconds() const;
double GetInvisibleVideoPlayTimeInSeconds() const;
double GetVideoDecodeSuspendedTimeInSeconds() const;
void StartInvisibleVideoTimeAcculator();
void PauseInvisibleVideoTimeAcculator();
bool HasOwnerHadValidVideo() const;
void AssertOnMainThreadAndNotShutdown() const;
void ReportTelemetry();
void ReportResultForVideo();
void ReportResultForVideoFrameStatistics(double aTotalPlayTimeS,
const nsCString& key);
// Helper class to measure times for playback telemetry stats
class TimeDurationAccumulator {
TimeDurationAccumulator() = default;
void Start() {
if (IsStarted()) {
mStartTime = Some(AwakeTimeStamp::NowLoRes());
void Pause() {
if (!IsStarted()) {
mSum = (AwakeTimeStamp::NowLoRes() - mStartTime.value());
mStartTime = Nothing();
bool IsStarted() const { return mStartTime.isSome(); }
double GetAndClearTotal() {
MOZ_ASSERT(!IsStarted(), "only call this when accumulator is paused");
double total = mSum.ToSeconds();
mStartTime = Nothing();
mSum = AwakeTimeDuration();
return total;
double PeekTotal() const {
if (!IsStarted()) {
return mSum.ToSeconds();
return (AwakeTimeStamp::NowLoRes() - mStartTime.value()).ToSeconds();
Maybe<AwakeTimeStamp> mStartTime;
AwakeTimeDuration mSum;
// The owner is HTMLMediaElement that is guaranteed being always alive during
// our whole life cycle.
TelemetryProbesReporterOwner* mOwner;
// Total time an element has spent on playing.
TimeDurationAccumulator mTotalPlayTime;
// Total time a VIDEO element has spent playing while the corresponding media
// element is invisible.
TimeDurationAccumulator mInvisibleVideoPlayTime;
// Total time a VIDEO has spent in video-decode-suspend mode.
TimeDurationAccumulator mVideoDecodeSuspendedTime;
Visibility mMediaElementVisibility = Visibility::eInvisible;
} // namespace mozilla
#endif // DOM_TelemetryProbesReporter_H_