Web/API/MediaSource/isTypeSupported

The MediaSource.isTypeSupported() static method returns a Boolean value which is true if the given MIME type is likely to be supported by the current user agent. That is, if it can successfully create SourceBuffer objects for that MIME type. If the returned value is false, then the user agent is certain that it cannot access media of the specified format.

Syntax

var isItSupported = mediaSource.isTypeSupported(mimeType);

Parameters

mimeType: The MIME media type that you want to test support for in the current browser. This may include the codecs parameter to provide added details about the codecs used within the file.

Return value

A Boolean which is true if the browser feels that it can probably play media of the specified type. This is not a guarantee, however, and your code must be prepared for the possibility that the media will not play correctly if at all. A value of false is a guarantee that media of the given type will not play, however.

All web APIs that work with media files use a "no/maybe/probably" approach (or, in this case, "no or probably") when determining if a media type can be used. This is because media files are complex, intricate constructs with far too many subtle variations to be absolutely certain of anything until you actually use the contents of the media.

Example

The following snippet is from an example written by Nick Desaulniers (view the full demo live, or download the source for further investigation.)

var assetURL = 'frag_bunny.mp4';
// Need to be specific for Blink regarding codecs
// ./mp4info frag_bunny.mp4 | grep Codec
var mimeCodec = 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"';

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 ExtensionsThe definition of 'isTypeSupported()' in that specification.	Recommendation	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`isTypeSupported` Experimental'	Chrome Full support 23	Edge Full support 12	Firefox Full support 42 Full support 42 No support 25 — 42 Notes' Disabled' Notes' Limited support to an allowed list of sites, for example YouTube, Netflix, and other popular streaming sites. The limitation was removed when Media Source Extensions was enabled by default in Firefox 42. Disabled' From version 25 until version 42 (exclusive): this feature is behind the `media.mediasource.enabled` preference. To change preferences in Firefox, visit about:config.	IE Full support 11 Notes' Full support 11 Notes' Notes' Only works on Windows 8+.	Opera Full support 15	Safari Full support 8	WebView Android Full support 4.4.3	Chrome Android Full support 25	Firefox Android Full support 41	Opera Android Full support 14	Safari iOS No support No	Samsung Internet Android Full support 1.5

Legend

Full support: Full support
No support: No support
Experimental. Expect behavior to change in the future.': Experimental. Expect behavior to change in the future.
See implementation notes.': See implementation notes.
User must explicitly enable this feature.': User must explicitly enable this feature.