MediaStream: getTrackById() method
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2017.
The getTrackById()
method of the MediaStream
interface
returns a MediaStreamTrack
object representing the track with the specified ID
string. If there is no track with the specified ID, this method returns null
.
Syntax
js
getTrackById(id)
Parameters
id
-
A string which identifies the track to be returned.
Return value
If a track is found for which MediaStreamTrack.id
matches the specified
id
string, that MediaStreamTrack
object is returned.
Otherwise, the returned value is null
.
Examples
This example activates a commentary track on a video by ducking the audio level of the main audio track to 50%, then enabling the commentary track.
js
stream.getTrackById("primary-audio-track").applyConstraints({ volume: 0.5 });
stream.getTrackById("commentary-track").enabled = true;
Specifications
Specification |
---|
Media Capture and Streams # dom-mediastream-gettrackbyid |
Browser compatibility
BCD tables only load in the browser