The read-only creationTime property on the VideoPlaybackQuality interface reports the number of milliseconds since the browsing context was created this quality sample was recorded.

A DOMHighResTimeStamp object which indicates the number of milliseconds that elapsed between the time the browsing context was created and the time at which this sample of the video quality was obtained.

For details on how the time is determined, see Performance.now().

This example calls getVideoPlaybackQuality() to obtain a VideoPlaybackQuality object, then determines what percentage of frames have been lost by either corruption or being dropped. If that exceeds 10% (0.1), a function called lostFramesThresholdExceeded() is called to, perhaps, update a quality indicator to show an increase in frame loss.

const videoElem = document.getElementById("my_vid");
const quality = videoElem.getVideoPlaybackQuality();

if (
  (quality.corruptedVideoFrames + quality.droppedVideoFrames) /
    quality.totalVideoFrames >
  0.1
) {
  lostFramesThresholdExceeded();
}

• The HTMLVideoElement.getVideoPlaybackQuality() method, which returns VideoPlaybackQuality objects