MediaSource.readyState

Experimental: 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 receive SourceBuffer objects.
ended: The source is attached to a media element but the stream has been ended via a call to MediaSource.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
Media Source Extensions™ # dom-mediasource-readystate

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`readyState`	23	12	42	11 Only works on Windows 8+.	15	8	4.4.3	33	41	14	13 Exposed in Mobile Safari on iPad but not on iPhone.	2.0