MediaTrackSettings: echoCancellation property
  The MediaTrackSettings dictionary's
  echoCancellation property is a Boolean value whose value
  indicates whether or not echo cancellation is enabled on an audio track. This lets you
  determine what value was selected to comply with your specified constraints for this
  property's value as described in the
  MediaTrackConstraints.echoCancellation property you provided when calling
  either getUserMedia() or
  MediaStreamTrack.applyConstraints().
Echo cancellation is a feature which attempts to prevent echo effects on a two-way audio connection by attempting to reduce or eliminate crosstalk between the user's output device and their input device. For example, it might apply a filter that negates the sound being produced on the speakers from being included in the input track generated from the microphone.
  If needed, you can determine whether or not this constraint is supported by checking
  the value of MediaTrackSupportedConstraints.echoCancellation as returned
  by a call to MediaDevices.getSupportedConstraints(). However, typically
  this is unnecessary since browsers will ignore any constraints they're unfamiliar with.
  Because RTP doesn't include this information, tracks associated with a
  WebRTC RTCPeerConnection
  will never include this property.
Value
  A Boolean value which is true if the track has echo cancellation
  functionality enabled or false if echo cancellation is disabled.
Examples
See the Constraint exerciser example.
Specifications
| Specification | 
|---|
| Media Capture and Streams # dom-mediatrackconstraintset-echocancellation | 
Browser compatibility
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