Web/API/SourceBuffer/abort

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This is an experimental technologyCheck the Browser compatibility table carefully before using this in production.

The abort() method of the SourceBuffer interface aborts the current segment and resets the segment parser.

Syntax

sourceBuffer.abort();

Parameters

None.

Return value

undefined.

Exceptions

Exception	Explanation
`InvalidStateError`	The `MediaSource.readyState` property of the parent media source is not equal to `open`, or this `SourceBuffer` has been removed from the `MediaSource`.

Example

The spec description of abort() is somewhat confusing — consider for example step 1 of reset parser state. The MSE API is fully asynchronous, but this step seems to suggest a synchronous (blocking) operation, which doesn't make sense.

Saying that, current implementations can be useful in certain situations, when you want to stop the current append (or whatever) operation occuring on a sourcebuffer, and then immediately start performing operations on it again. For example, consider this code:

sourceBuffer.addEventListener('updateend', function (_) {
  ...
});

sourceBuffer.appendBuffer(buf);

Let's say that after the call to appendBuffer BUT before the updateend event fires (i.e. a buffer is being appended but the operation has not yet completed) a user "scrubs" the video seeking to a new point in time. In this case you would want to manually call abort() on the source buffer to stop the decoding of the current buffer, then fetch and append the newly requested segment that relates to the current new position of the video.

You can see something similar in action in Nick Desaulnier's bufferWhenNeeded demo — in line 48, an event listener is added to the playing video so a function called seek() is run when the seeking event fires. In lines 92-101, the seek() function is defined — note that abort() is called if MediaSource.readyState is set to open, which means that it is ready to receive new source buffers — at this point it is worth aborting the current segment and just getting the one for the new seek position (see checkBuffer() and getCurrentSegment().)

Specifications

Specification	Status	Comment
Media Source ExtensionsThe definition of 'abort()' 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
`abort`	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 (needs to be set to `true`). 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 No support No	Opera Android Full support 14	Safari iOS No support No	Samsung Internet Android Full support 2.0

Legend

Full support: Full support
No support: No support
See implementation notes.': See implementation notes.
User must explicitly enable this feature.': User must explicitly enable this feature.