This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The readyState
read-only property of the MediaSource
interface returns an enum representing the state of the current MediaSource
. The three possible values are:
closed
: The source is not currently attached to a media element.open
: The source is attached to a media element and ready to receiveSourceBuffer
objects.ended
: The source is attached to a media element but the stream has been ended via a call toMediaSource.endOfStream()
.
Syntax
var myReadyState = mediaSource.readyState;
Value
A DOMString
.
Example
The following snippet is from a simple example written by Nick Desaulniers (view the full demo live, or download the source for further investigation.)
if ('MediaSource' in window && MediaSource.isTypeSupported(mimeCodec)) {
var mediaSource = new MediaSource;
//console.log(mediaSource.readyState); // closed
video.src = URL.createObjectURL(mediaSource);
mediaSource.addEventListener('sourceopen', sourceOpen);
} else {
console.error('Unsupported MIME type or codec: ', mimeCodec);
}
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();
video.play();
//console.log(mediaSource.readyState); // ended
});
sourceBuffer.appendBuffer(buf);
});
};
Specifications
Specification | Status | Comment |
---|---|---|
Media Source Extensions The definition of 'readyState' 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+.