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MediaSource: sourceclose 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.

The sourceclose event is fired when a MediaSource object's readyState changes to "closed". This indicates that the MediaSource has been detached from the media element.

Syntax

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

addEventListener("sourceclose", (event) => { })

onsourceclose = (event) => { }

Event type

A generic Event.

Examples

>

Handling the sourceclose event

This example demonstrates detaching a media element from a MediaSource and handling the sourceclose event for proper resource management. The code sets up a MediaSource, attaches it to a video element, and listens for the sourceclose event. When the event fires, it performs cleanup tasks (revokeObjectURL).

const video = document.getElementById("myVideo");
const mediaSource = new MediaSource();

video.src = URL.createObjectURL(mediaSource);

mediaSource.addEventListener("sourceopen", (event) => {
  const sourceBuffer = mediaSource.addSourceBuffer(
    'video/mp4; codecs="avc1.42E01E"',
  );
  fetch("video-data.mp4")
    .then((response) => response.arrayBuffer())
    .then((data) => {
      sourceBuffer.appendBuffer(data);
    });
});

function detachMediaSource() {
  video.src = null; // Detach the MediaSource
}

mediaSource.addEventListener("sourceclose", (event) => {
  console.log("MediaSource sourceclose:", event);
  // Perform cleanup tasks here, e.g., release resources, update UI
  URL.revokeObjectURL(video.src); // Clean up the object URL
});

// Call detachMediaSource() when appropriate, e.g., on a button click
document
  .getElementById("detachButton")
  .addEventListener("click", detachMediaSource);

Specifications

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
sourceclose_event 53
31–53The onsourceclose event handler property is not supported.
17
12–17The onsourceclose event handler property is not supported.
87
42–87The onsourceclose event handler property is not supported.
40
18–40The onsourceclose event handler property is not supported.
10.1
8–10.1The onsourceclose event handler property is not supported.
53
31–53The onsourceclose event handler property is not supported.
87
41–87The onsourceclose event handler property is not supported.
41
18–41The onsourceclose event handler property is not supported.
13Exposed in Mobile Safari on iPad but not on iPhone.
6.0
2.0–6.0The onsourceclose event handler property is not supported.
53
4.4.3–53The onsourceclose event handler property is not supported.
No

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https://developer.mozilla.org/en-US/docs/Web/API/MediaSource/sourceclose_event