ortc-5.js

var audioTrack = mediaStreamLocal.getAudioTracks()[0];
var videoTrack = mediaStreamLocal.getVideoTracks()[0];
var audioSender = new RtpSender(audioTrack, dtlsTr);
var videoSender = new RtpSender(videoTrack, dtlsTr);
var audioReceiver = new RtpReceiver(dtlsTr, "audio");
var videoReceiver = new RtpReceiver(dtlsTr, "video");