Navigator: getUserMedia() method

Syntax

getUserMedia(constraints, successCallback, errorCallback)

Parameters

constraints

An object specifying the types of media to request, along with any requirements for each type. For details, see the constraints section under the modern MediaDevices.getUserMedia() method, as well as the article Capabilities, constraints, and settings.

successCallback

A function which is invoked when the request for media access is approved. The function is called with one parameter: the MediaStream object that contains the media stream. Your callback can then assign the stream to the desired object (such as an <audio> or <video> element), as shown in the following example:

js

function successCallback(stream) {
  const video = document.querySelector("video");
  video.srcObject = stream;
  video.onloadedmetadata = (e) => {
    // Do something with the video here.
  };
}

errorCallback

When the call fails, the function specified in the errorCallback is invoked with an object as its sole argument; this object is modeled on DOMException.

Return value

None (undefined).

Examples

Width and height

Here's an example of using getUserMedia(), including code to cope with various browsers' prefixes. Note that this is the deprecated way of doing it: See the Examples section under the MediaDevices.getUserMedia() for modern examples.

navigator.getUserMedia =
  navigator.getUserMedia ||
  navigator.webkitGetUserMedia ||
  navigator.mozGetUserMedia;

if (navigator.getUserMedia) {
  navigator.getUserMedia(
    { audio: true, video: { width: 1280, height: 720 } },
    (stream) => {
      const video = document.querySelector("video");
      video.srcObject = stream;
      video.onloadedmetadata = (e) => {
        video.play();
      };
    },
    (err) => {
      console.error(`The following error occurred: ${err.name}`);
    },
  );
} else {
  console.log("getUserMedia not supported");
}

Specifications

Browser compatibility

See also

• MediaDevices.getUserMedia() that replaces this deprecated method.
• WebRTC - the introductory page to the API
• Media Capture and Streams API - the API for the media stream objects
• Taking webcam photos - a tutorial on using getUserMedia() for taking photos rather than video.