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 "inactive", raise a DOMInvalidState
error and terminate these steps. IfMediaRecorder.state
is not "inactive", continue to the next step. -
Raise a
dataavailable
event containing aBlob
of the currently captured data (the Blob is available under the event'sdata
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 |
---|
MediaStream Recording # dom-mediarecorder-requestdata |
Browser compatibility
BCD tables only load in the browser
See also
- Using the MediaRecorder API
- Web Dictaphone: MediaRecorder + getUserMedia + Web Audio API visualization demo, by Chris Mills (source on GitHub.)
- simpl.info MediaStream Recording demo, by Sam Dutton.
Navigator.getUserMedia