MediaSource: readyState property

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().

Value

A string.

Examples

The following snippet is from a simple example written by Nick Desaulniers (view the full demo live, or download the source for further investigation). The function getMediaSource(), which is not defined here, returns a MediaSource.

js
let mediaSource;

if ("MediaSource" in window && MediaSource.isTypeSupported(mimeCodec)) {
  mediaSource = getMediaSource();
  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
  const sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
  fetchAB(assetURL, (buf) => {
    sourceBuffer.addEventListener("updateend", () => {
      mediaSource.endOfStream();
      video.play();
      console.log(mediaSource.readyState); // ended
    });
    sourceBuffer.appendBuffer(buf);
  });
}

Specifications

Specification
Media Source Extensions™
# dom-mediasource-readystate

Browser compatibility

BCD tables only load in the browser

See also