Bug 1243857 - Enable duplex audio for Windows/WASAPI. r=jesup

MozReview-Commit-ID: 4h1JTGSHr2v

dom/media/webrtc/MediaEngineWebRTC.cpp

@@ -12,6 +12,9 @@
 #include "prenv.h"
 
 #include "mozilla/Logging.h"
+#ifdef XP_WIN
+#include "mozilla/WindowsVersion.h"
+#endif
 
 static mozilla::LogModule*
 GetUserMediaLog()
@@ -290,6 +293,16 @@ MediaEngineWebRTC::EnumerateVideoDevices(dom::MediaSourceEnum aMediaSource,
 #endif
 }
 
+bool
+MediaEngineWebRTC::SupportsDuplex()
+{
+#ifndef XP_WIN
+  return mFullDuplex;
+#else
+  return IsVistaOrLater() && mFullDuplex;
+#endif
+}
+
 void
 MediaEngineWebRTC::EnumerateAudioDevices(dom::MediaSourceEnum aMediaSource,
                                          nsTArray<RefPtr<MediaEngineAudioSource> >* aASources)
@@ -339,7 +352,7 @@ MediaEngineWebRTC::EnumerateAudioDevices(dom::MediaSourceEnum aMediaSource,
   }
 
   if (!mAudioInput) {
-    if (mFullDuplex) {
+    if (SupportsDuplex()) {
       // The platform_supports_full_duplex.
       mAudioInput = new mozilla::AudioInputCubeb(mVoiceEngine);
     } else {
@@ -383,7 +396,7 @@ MediaEngineWebRTC::EnumerateAudioDevices(dom::MediaSourceEnum aMediaSource,
       aASources->AppendElement(aSource.get());
     } else {
       AudioInput* audioinput = mAudioInput;
-      if (mFullDuplex) {
+      if (SupportsDuplex()) {
         // The platform_supports_full_duplex.
 
         // For cubeb, it has state (the selected ID)

dom/media/webrtc/MediaEngineWebRTC.h

@@ -551,6 +551,9 @@ public:
   // before invoking Shutdown on this class.
   void Shutdown() override;
 
+  // Returns whether the host supports duplex audio stream.
+  bool SupportsDuplex();
+
   void EnumerateVideoDevices(dom::MediaSourceEnum,
                              nsTArray<RefPtr<MediaEngineVideoSource>>*) override;
   void EnumerateAudioDevices(dom::MediaSourceEnum,

modules/libpref/init/all.js

@@ -446,7 +446,7 @@ pref("media.navigator.audio.full_duplex", false);
 #elif defined(XP_WIN)
 pref("media.peerconnection.capture_delay", 50);
 pref("media.getusermedia.playout_delay", 40);
-pref("media.navigator.audio.full_duplex", false);
+pref("media.navigator.audio.full_duplex", true);
 #elif defined(ANDROID)
 pref("media.peerconnection.capture_delay", 100);
 pref("media.getusermedia.playout_delay", 100);