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MediaRecorder.onstart

The MediaRecorder.onstartevent handler (part of the MediaRecorder API) handles the start event, allowing you to run code in response to media recording being started by a MediaRecorder.

The start event is thrown as a result of the MediaRecorder.start() method being invoked. At this point, the data starts being gathered into a Blob.

Syntax

MediaRecorder.onstart = function(event) { ... }
MediaRecorder.addEventListener('start', function(event) { ... })

Example

...

  record.onclick = function() {
    mediaRecorder.start();
    console.log("recorder started");
  }

  mediaRecorder.onstart = function() {
    // do something in response to
    // recording being started
  }

...

Properties

None.

Specifications

Specification Status Comment
MediaStream Recording
The definition of 'MediaRecorder.onstart' in that specification.
Working Draft Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 47[2] 25.0 (25.0) Not supported Not supported Not supported
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support Not supported Not supported 25.0 (25.0) 1.3[1] Not supported Not supported Not supported Not supported

[1] The intial Firefox OS implementation only supported audio recording.

[2] To try this feature on Chrome, enable Experimental Web Platform features from chrome://flags . Currently only video is supported, not audio.

See also

Document Tags and Contributors

 Contributors to this page: jpmedley, Sebastianz, chrisdavidmills, teoli, kscarfone
 Last updated by: jpmedley,