Improve WebRTC audio quality

packages/rocketchat-webrtc/WebRTCClass.coffee

@@ -324,9 +324,30 @@ class WebRTCClass
 
 		return peerConnection
 
+	_getUserMedia: (media, onSuccess, onError) ->
+		onSuccessLocal = (stream) ->
+			if AudioContext? and stream.getAudioTracks().length > 0
+				audioContext = new AudioContext
+				source = audioContext.createMediaStreamSource(stream)
+
+				volume = audioContext.createGain()
+				source.connect(volume)
+				peer = audioContext.createMediaStreamDestination()
+				volume.connect(peer)
+				volume.gain.value = 0.6
+
+				stream.removeTrack(stream.getAudioTracks()[0])
+				stream.addTrack(peer.stream.getAudioTracks()[0])
+				stream.volume = volume
+
+			onSuccess(stream)
+
+		navigator.getUserMedia media, onSuccessLocal, onError
+
+
 	getUserMedia: (media, onSuccess, onError=@onError) ->
 		if media.desktop isnt true
-			navigator.getUserMedia media, onSuccess, onError
+			@_getUserMedia media, onSuccess, onError
 			return
 
 		if @screenShareAvailable isnt true
@@ -371,7 +392,7 @@ class WebRTCClass
 					video:
 						mozMediaSource: 'window'
 						mediaSource: 'window'
-				navigator.getUserMedia media, getScreenSuccess, onError
+				@_getUserMedia media, getScreenSuccess, onError
 			else
 				ChromeScreenShare.getSourceId (id) =>
 					console.log id
@@ -384,7 +405,7 @@ class WebRTCClass
 								maxWidth: 1280
 								maxHeight: 720
 
-					navigator.getUserMedia media, getScreenSuccess, onError
+					@_getUserMedia media, getScreenSuccess, onError
 
 		if @navigator is 'firefox' or not media.audio? or media.audio is false
 			getScreen()
@@ -395,7 +416,7 @@ class WebRTCClass
 			getAudioError = =>
 				getScreen()
 
-			navigator.getUserMedia {audio: media.audio}, getAudioSuccess, getAudioError
+			@_getUserMedia {audio: media.audio}, getAudioSuccess, getAudioError
 
 
 	###

packages/rocketchat-webrtc/adapter.js

@@ -2,4 +2,5 @@ window.RTCPeerConnection = window.RTCPeerConnection || window.mozRTCPeerConnecti
 window.RTCSessionDescription = window.RTCSessionDescription || window.mozRTCSessionDescription || window.webkitRTCSessionDescription;
 window.RTCIceCandidate = window.RTCIceCandidate || window.mozRTCIceCandidate || window.webkitRTCIceCandidate;
 window.RTCSessionDescription = window.RTCSessionDescription || window.mozRTCSessionDescription || window.webkitRTCSessionDescription;
-navigator.getUserMedia = navigator.getUserMedia || navigator.mozGetUserMedia || navigator.webkitGetUserMedia;
+window.AudioContext = window.AudioContext || window.mozAudioContext || window.webkitAudioContext;
\ No newline at end of file
+navigator.getUserMedia = navigator.getUserMedia || navigator.mozGetUserMedia || navigator.webkitGetUserMedia;