WebRTC: Switch camera

[Nizar Boukhari]

Hi everyone,

I want to be able to switch the camera during a WebRTC communication. I already posted in SO but im still waiting for an answer. here is the link to the post => stackoverflow

basically I get the media sources using the following command => "MediaStreamTrack.getSources", it gives me two sources (since the code is running in a mobile device) like so => 

{
    id: "id_source_1" | "id_source_2",
    facing: "user" | "environment",
    kind: "kind_1" | "kind_2",
    label: "label_1" | "label_2"
 }

then during the call the user clicks a button to switch the camera that will execute the following code => 

var mediaParams = {
       audio: true,
       video: { deviceId : source_2.id},
       options: {
           muted: true,
           mirror: true
       },
       elemId: 'localVideo'
};

callingSession.getUserMedia(mediaParams, function (error, stream) {
if (error) {
   console.error('error getting user media');
} else {
          var oldVideoTracks = callingSession.localStream.getVideoTracks();      
          var newVideoTracks = stream.getVideoTracks();

          if (oldVideoTracks.length > 0 && newVideoTracks.length > 0) {
               callingSession.localStream.removeTrack(oldVideoTracks[0]);
               callingSession.localStream.addTrack(newVideoTracks[0]);
          } 
       }
 });

apparently im doing something wrong, because the "stream" in the callback of the "getUserMedia" method is still the exact same old stream, even if the method has new constraint.

how can I switch the camera without renegociating the call, or change the video resolution or any changes that imply new constraints.

I really need to understand whats the failure in this code :(

Thank you very much.

[Vincent Bian]

Do you find the solution of switch the camera without renegotiating the call ?

[Diogo Moraes]

You can now use the replaceTrack method to change the tracks that are being sent without renegociating:

localStream.getTracks().forEach(function(track) {

    track.stop();

});

// after the getUserMedia with the new constraints

peerConnection.getSenders().map(sender => sender.replaceTrack(newStream.getTracks().find(t => t.kind === sender.track.kind), newStream))