We're looking for a person or people to help audit MDN to find places we could speed up. Is this you or someone you know? Check out the RFP: https://mzl.la/2IHcMiE



The MediaDevices interface provides access to connected media input devices like cameras and microphones, as well as screensharing.


Inherits properties from its parent EventTarget.

Event handlers

Returns the event handler for the devicechange event type.


Inherits methods from its parent EventTarget.

Registers an event handler to a specific event type.
Obtains an array of information about the media input and output devices available on the system.
With the user's permission through a prompt, turns on a camera or screensharing and/or a microphone on the system and provides a MediaStream containing a video track and/or an audio track with the input.
Removes an event listener.


'use strict';

// Put variables in global scope to make them available to the browser console.
var video = document.querySelector('video');
var constraints = window.constraints = {
  audio: false,
  video: true
var errorElement = document.querySelector('#errorMsg');

.then(function(stream) {
  var videoTracks = stream.getVideoTracks();
  console.log('Got stream with constraints:', constraints);
  console.log('Using video device: ' + videoTracks[0].label);
  stream.onended = function() {
    console.log('Stream ended');
  window.stream = stream; // make variable available to browser console
  video.srcObject = stream;
.catch(function(error) {
  if (error.name === 'ConstraintNotSatisfiedError') {
    errorMsg('The resolution ' + constraints.video.width.exact + 'x' +
        constraints.video.width.exact + ' px is not supported by your device.');
  } else if (error.name === 'PermissionDeniedError') {
    errorMsg('Permissions have not been granted to use your camera and ' +
      'microphone, you need to allow the page access to your devices in ' +
      'order for the demo to work.');
  errorMsg('getUserMedia error: ' + error.name, error);

function errorMsg(msg, error) {
  errorElement.innerHTML += '<p>' + msg + '</p>';
  if (typeof error !== 'undefined') {


Specification Status Comment
Media Capture and Streams
Candidate Recommendation Initial definition

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support (Yes) 36.0 (36.0) 未实现 未实现 未实现
enumerateDevices() 51.0 ? 未实现 未实现 未实现
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support 未实现 未实现 36.0 (36.0) 2.2 未实现 未实现 未实现 未实现
enumerateDevices() 未实现 未实现 ? ? 未实现 未实现 未实现 未实现

See also


 此页面的贡献者: Victorystick
 最后编辑者: Victorystick,