This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
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+.