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This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The MediaDevicesInfo
interface contains information on the available media input and output devices.
Properties
MediaDeviceInfo.deviceId
Read only- Returns a
DOMString
that is an identifier for the represented device that is persisted across sessions. It is un-guessable by other applications and unique to the origin of the calling application. It is reset when the user clears cookies (for Private Browsing, a different identifier is used that is not persisted across sessions). MediaDeviceInfo.groupId
Read only- Returns a
DOMString
that is a group identifier. Two devices have the same group identifier if they belong to the same physical device — for example a monitor with both a built-in camera and a microphone. MediaDeviceInfo.kind
Read only- Returns an enumerated value that is either
"videoinput"
,"audioinput"
or"audiooutput"
. MediaDeviceInfo.label
Read only- Returns a
DOMString
that is a label describing this device (for example "External USB Webcam"). Only available during active MediaStream use or when persistent permissions have been granted.
Methods
None.
Example
Here's an example of using mediaDevices.enumerateDevices()
.
if (!navigator.mediaDevices || !navigator.mediaDevices.enumerateDevices) { console.log("enumerateDevices() not supported."); return; } // List cameras and microphones. navigator.mediaDevices.enumerateDevices() .then(function(devices) { devices.forEach(function(device) { console.log(device.kind + ": " + device.label + " id = " + device.deviceId); }); }) .catch(function(err) { console.log(err.name + ": " + error.message); });
This might produce:
videoinput: id = csO9c0YpAf274OuCPUA53CNE0YHlIr2yXCi+SqfBZZ8= audioinput: id = RKxXByjnabbADGQNNZqLVLdmXlS0YkETYCIbg+XxnvM= audioinput: id = r2/xw1xUPIyZunfV1lGrKOma5wTOvCkWfZ368XCndm0=
or if one or more MediaStreams are active or persistent permissions are granted:
videoinput: FaceTime HD Camera (Built-in) id=csO9c0YpAf274OuCPUA53CNE0YHlIr2yXCi+SqfBZZ8= audioinput: default (Built-in Microphone) id=RKxXByjnabbADGQNNZqLVLdmXlS0YkETYCIbg+XxnvM= audioinput: Built-in Microphone id=r2/xw1xUPIyZunfV1lGrKOma5wTOvCkWfZ368XCndm0=
Specifications
Specification | Status | Comment |
---|---|---|
Media Capture and Streams The definition of 'MediaDevicesInfo' in that specification. |
Editor's Draft | Initial definition |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 55.0[1] | (Yes) | 39 | No support | ?[2] | No support |
Feature | Android | Android Webview | Edge | Firefox Mobile (Gecko) | Firefox OS (Gecko) | IE Phone | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|---|---|
Basic support | No support | ? | (Yes) | 39 | 2.5 | No support | ?[2] | No support | ? |
[1] For earlier versions, this interface is available through the adapter.js polyfill.
[2] This interface is available in Opera through the adapter.js polyfill.
See also
- WebRTC - the introductory page to the API