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MediaSource.duration

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The duration property of the MediaSource interface gets and sets the duration of the current media being presented.

Syntax

mediaSource.duration = 5.5; // 5.5 seconds

var myDuration = mediaSource.duration;

Value

A double. A value in seconds is expected.

Errors

The following errors may be thrown when setting a new value for this property.

Error	Explanation
`InvalidAccessError`	An attempt was made to set a duration value that was negative, or `NaN`.
`InvalidStateError`	`MediaSource.readyState` is not equal to `open`, or one or more of the `SourceBuffer` objects in `MediaSource.sourceBuffers` are being updated (i.e. their `SourceBuffer.updating` property is `true`.)

Example

The following snippet is based on a simple example written by Nick Desaulniers (view the full demo live, or download the source for further investigation.)

function sourceOpen (_) {
  //console.log(this.readyState); // open
  var mediaSource = this;
  var sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
  fetchAB(assetURL, function (buf) {
    sourceBuffer.addEventListener('updateend', function (_) {
      mediaSource.endOfStream();
      mediaSource.duration = 120;
      video.play();
      //console.log(mediaSource.readyState); // ended
    });
    sourceBuffer.appendBuffer(buf);
  });
};

...

Specifications

Specification	Status	Comment
Media Source Extensions The definition of 'duration' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibility

Feature	Chrome	Edge	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	23	(Yes)	25.0 (25.0)^[1] 42.0 (42.0)	11^[2]	15	8

Feature	Android	Edge	Firefox Mobile (Gecko)	Firefox OS (Gecko)	IE Phone	Opera Mobile	Safari Mobile
Basic support	4.4.4	(Yes)	No support	No support	11	30	No support

[1] Available after switching the about:config preference media.mediasource.enabled to true. In addition, support was limited to a whitelist of sites, for example YouTube, Netflix, and other popular streaming sites. The whitelist was removed and Media Source Extensions was enabled by default in 42+ for all sites.

[2] Only works on Windows 8+.

MediaSource.duration

Syntax

Value

Errors

Example

Specifications

Browser compatibility

See also