ManagedMediaSource: startstreaming event

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Note: This feature is available in Dedicated Web Workers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The startstreaming event of the ManagedMediaSource interface is fired when the streaming property changes from false to true. This indicates that the user agent needs more data to ensure uninterrupted playback, and the application should begin fetching and appending media segments.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

js
addEventListener("startstreaming", (event) => {});

onstartstreaming = (event) => {};

Event type

A generic Event.

Examples

Fetching data in response to startstreaming

This example creates a ManagedMediaSource, attaches it to a <video> element, and uses the startstreaming event to begin fetching and appending media data.

js
const videoUrl =
  "https://mdn.github.io/shared-assets/videos/flower-fragmented.mp4";
const mediaType = 'video/mp4; codecs="avc1.64001F, mp4a.40.2"';

if (ManagedMediaSource.isTypeSupported(mediaType)) {
  const video = document.createElement("video");
  const source = new ManagedMediaSource();

  video.controls = true;
  video.disableRemotePlayback = true;
  video.src = URL.createObjectURL(source);
  document.body.appendChild(video);

  source.addEventListener("sourceopen", () => {
    const sourceBuffer = source.addSourceBuffer(mediaType);

    source.addEventListener("startstreaming", async () => {
      console.log("startstreaming — fetching media data");
      const response = await fetch(videoUrl);
      const data = await response.arrayBuffer();
      sourceBuffer.appendBuffer(data);
    });
  });
}

Specifications

Specification
Media Source Extensions™
# dfn-startstreaming

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
startstreaming event
Experimental
Chrome – No support
Chrome
footnote No support
Edge – No support
Edge
footnote No support
Firefox – No support
Firefox
footnote No support
Opera – No support
Opera
footnote No support
Safari – Full support
Safari 17 (Release date: 2023-09-18)
footnote Full support
Chrome Android – No support
Chrome Android
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Opera Android – No support
Opera Android
footnote No support
Safari on iOS – Full support
Safari on iOS 17.1 (Release date: 2023-10-25)
footnote Full support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – No support
WebView Android
footnote No support
WebView on iOS – Full support
WebView on iOS 17.1 (Release date: 2023-10-25)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.

See also