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MediaSource: activeSourceBuffers property

The activeSourceBuffers read-only property of the MediaSource interface returns a SourceBufferList object containing a subset of the SourceBuffer objects contained within sourceBuffers — the list of objects providing the selected video track, enabled audio tracks, and shown/hidden text tracks.

Value

A SourceBufferList containing the SourceBuffer objects for each of the active tracks.

Examples

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). The function getMediaSource(), which is not defined here, returns a MediaSource.

js

const mediaSource = getMediaSource();

function sourceOpen() {
  console.log(mediaSource.readyState); // open
  const sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
  fetchAB(assetURL, (buf) => {
    sourceBuffer.addEventListener("updateend", () => {
      mediaSource.endOfStream();
      console.log(mediaSource.activeSourceBuffers);
      // will contain the source buffer that was added above,
      // as it is selected for playing in the video player
      video.play();
      console.log(mediaSource.readyState); // ended
    });
    sourceBuffer.appendBuffer(buf);
  });
}

// …

Specifications

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
activeSourceBuffers 23 12 42
11Only works on Windows 8+.
15 8 4.4.3 25 41 14
13Exposed in Mobile Safari on iPad but not on iPhone.
1.5

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/MediaSource/activeSourceBuffers