Web/API/VideoPlaybackQuality/droppedVideoFrames

The read-only droppedVideoFrames property of the VideoPlaybackQuality interface returns the number of video frames which have been dropped rather than being displayed since the last time the media was loaded into the HTMLVideoElement.

Syntax

value = videoPlaybackQuality.droppedVideoFrames;

Value

An unsigned 64-bit value indicating the number of frames that have been dropped since the last time the media in the <video> element was loaded or reloaded. This information can be used to determine whether or not to downgrade the video stream to avoid dropping frames.

Frames are typically dropped either before or after decoding them, when it's determined that it will not be possible to draw them to the screen at the correct time.

Example

This example calls getVideoPlaybackQuality() to obtain a VideoPlaybackQuality object, then determines what percentage of frames have been dropped. That value is then presented in an element for the user's reference.

var videoElem = document.getElementById("my_vid");
var percentElem = document.getElementById("percent");
var quality = videoElem.getVideoPlaybackQuality();

var dropPercent = (quality.droppedVideoFrames/quality.totalVideoFrames)*100;
percentElem.innerText = Math.trunc(dropPercent).toString(10);

Specifications

Specification	Status	Comment
Media Playback QualityThe definition of 'VideoPlaybackQuality.droppedVideoFrames' in that specification.	Editor's Draft	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`droppedVideoFrames` Experimental'	Chrome Full support 23	Edge Full support 12	Firefox Full support 42 Full support 42 No support 25 — 42 Notes' Disabled' Notes' Limited support to an allowed list of sites, for example YouTube, Netflix, and other popular streaming sites. The limitation was removed when Media Source Extensions was enabled by default in Firefox 42. Disabled' From version 25 until version 42 (exclusive): this feature is behind the `media.mediasource.enabled` preference. To change preferences in Firefox, visit about:config.	IE Full support 11 Notes' Full support 11 Notes' Notes' Only works on Windows 8+.	Opera Full support 15	Safari Full support 8	WebView Android Full support 4.4.3	Chrome Android ?	Firefox Android No support No	Opera Android Full support 14	Safari iOS No support No	Samsung Internet Android ?

Legend

Full support: Full support
No support: No support
Compatibility unknown: Compatibility unknown
Experimental. Expect behavior to change in the future.': Experimental. Expect behavior to change in the future.
See implementation notes.': See implementation notes.
User must explicitly enable this feature.': User must explicitly enable this feature.