Web/API/MediaRecorder/requestData

The MediaRecorder.requestData() method (part of the MediaRecorder API) is used to raise a dataavailable event containing a Blob object of the captured media as it was when the method was called. This can then be grabbed and manipulated as you wish.

When the requestData() method is invoked, the browser queues a task that runs the following steps:

If MediaRecorder.state is not "recording", raise a DOM InvalidState error and terminate these steps. If MediaRecorder.state is "recording", continue to the next step.
Raise a dataavailable event containing a Blob of the currently captured data (the Blob is available under the event's data attribute.)
Create a new Blob and place subsequently captured data into it.

Syntax

MediaRecorder.requestData()

Errors

An InvalidState error is raised if the requestData() method is called while the MediaRecorder object’s MediaRecorder.state is not "recording" — the media cannot be captured if recording is not occurring.

Example

...

  captureMedia.onclick = function() {
    mediaRecorder.requestData();
    // makes snapshot available of data so far
    // ondataavailable fires, then capturing continues
    // in new Blob
  }

...

Specifications

Specification	Status	Comment
MediaStream RecordingThe definition of 'MediaRecorder.requestData()' in that specification.	Working Draft	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
`requestData`	Chrome Full support 49	Edge Full support 79	Firefox Full support 25	IE No support No	Opera Full support 36	Safari No support No	WebView Android Full support 49	Chrome Android Full support 49	Firefox Android Full support 25	Opera Android Full support 36	Safari iOS No support No	Samsung Internet Android Full support 5.0

Legend

Full support: Full support
No support: No support