MediaDevices

The MediaDevices interface provides access to connected media input devices like cameras and microphones, as well as screen sharing. In essence, it lets you obtain access to any hardware source of media data.

EventTarget MediaDevices

Instance properties

Inherits properties from its parent interface, EventTarget.

Instance methods

Inherits methods from its parent interface, EventTarget.

enumerateDevices()

Obtains an array of information about the media input and output devices available on the system.

getSupportedConstraints()

Returns an object conforming to MediaTrackSupportedConstraints indicating which constrainable properties are supported on the MediaStreamTrack interface. See Media Streams API to learn more about constraints and how to use them.

getDisplayMedia()

Prompts the user to select a display or portion of a display (such as a window) to capture as a MediaStream for sharing or recording purposes. Returns a promise that resolves to a MediaStream.

getUserMedia()

With the user's permission through a prompt, turns on a camera and/or a microphone on the system and provides a MediaStream containing a video track and/or an audio track with the input.

selectAudioOutput()

Prompts the user to select a specific audio output device.

Events

devicechange

Fired when a media input or output device is attached to or removed from the user's computer.

Example

js

// Put variables in global scope to make them available to the browser console.
const video = document.querySelector("video");
const constraints = {
  audio: false,
  video: true,
};

navigator.mediaDevices
  .getUserMedia(constraints)
  .then((stream) => {
    const videoTracks = stream.getVideoTracks();
    console.log("Got stream with constraints:", constraints);
    console.log(`Using video device: ${videoTracks[0].label}`);
    stream.onremovetrack = () => {
      console.log("Stream ended");
    };
    video.srcObject = stream;
  })
  .catch((error) => {
    if (error.name === "OverconstrainedError") {
      console.error(
        `The resolution ${constraints.video.width.exact}x${constraints.video.height.exact} px is not supported by your device.`
      );
    } else if (error.name === "NotAllowedError") {
      console.error(
        "You need to grant this page permission to access your camera and microphone."
      );
    } else {
      console.error(`getUserMedia error: ${error.name}`, error);
    }
  });

Specifications

Specification
Media Capture and Streams
# mediadevices

Browser compatibility

BCD tables only load in the browser

See also