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MediaSource: MediaSource() constructor

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.

The MediaSource() constructor of the MediaSource interface constructs and returns a new MediaSource object with no associated source buffers.

Syntax

new MediaSource()

Parameters

None.

Examples

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

const video = document.querySelector("video");

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

if ("MediaSource" in window && MediaSource.isTypeSupported(mimeCodec)) {
  const 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);
}

// …

Specifications

Specification
Media Source Extensions™> # dom-mediasource-constructor>

Browser compatibility