Bug 1279049 - add sdp handling for audio FEC, r=jesup

MozReview-Commit-ID: J0ax8TnR3p8

--HG--
extra : transplant_source : %D5Y%15%E6%C3d%F5%BD%9B%D7%CC%BA%DA%DE%12.%88%DD%A1%5B

media/webrtc/signaling/src/jsep/JsepCodecDescription.h

@@ -172,6 +172,7 @@ class JsepAudioCodecDescription : public JsepCodecDescription {
         // We prefer to receive stereo, if available.
         opusParams.stereo = 1;
       }
+      opusParams.useInBandFec = mFECEnabled ? 1 : 0;
       msection.SetFmtp(SdpFmtpAttributeList::Fmtp(mDefaultPt, opusParams));
     }
   }
@@ -187,6 +188,10 @@ class JsepAudioCodecDescription : public JsepCodecDescription {
 
       mMaxPlaybackRate = opusParams.maxplaybackrate;
       mForceMono = !opusParams.stereo;
+      // draft-ietf-rtcweb-fec-03.txt section 4.2 says support for FEC
+      // at the received side is declarative and can be negotiated
+      // separately for either media direction.
+      mFECEnabled = opusParams.useInBandFec;
     }
 
     return true;

media/webrtc/signaling/src/peerconnection/PeerConnectionImpl.cpp

@@ -876,7 +876,8 @@ class ConfigureCodec {
       mVP8MaxFs(0),
       mVP8MaxFr(0),
       mUseTmmbr(false),
-      mUseRemb(false)
+      mUseRemb(false),
+      mUseAudioFec(false)
     {
 #ifdef MOZ_WEBRTC_OMX
       // Check to see if what HW codecs are available (not in use) at this moment.
@@ -945,13 +946,21 @@ class ConfigureCodec {
 
       // REMB is enabled by default, but can be disabled from about:config
       branch->GetBoolPref("media.navigator.video.use_remb", &mUseRemb);
+
+      branch->GetBoolPref("media.navigator.audio.use_fec", &mUseAudioFec);
     }
 
     void operator()(JsepCodecDescription* codec) const
     {
       switch (codec->mType) {
         case SdpMediaSection::kAudio:
-          // Nothing to configure here, for now.
+          {
+            JsepAudioCodecDescription& audioCodec =
+              static_cast<JsepAudioCodecDescription&>(*codec);
+            if (audioCodec.mName == "opus") {
+              audioCodec.mFECEnabled = mUseAudioFec;
+            }
+          }
           break;
         case SdpMediaSection::kVideo:
           {
@@ -1016,6 +1025,7 @@ class ConfigureCodec {
     int32_t mVP8MaxFr;
     bool mUseTmmbr;
     bool mUseRemb;
+    bool mUseAudioFec;
 };
 
 nsresult

media/webrtc/signaling/src/sdp/SdpAttribute.h

@@ -1243,11 +1243,13 @@ public:
   {
   public:
     enum { kDefaultMaxPlaybackRate = 48000,
-           kDefaultStereo = 0 };
+           kDefaultStereo = 0,
+           kDefaultUseInBandFec = 0 };
     OpusParameters() :
       Parameters(SdpRtpmapAttributeList::kOpus),
       maxplaybackrate(kDefaultMaxPlaybackRate),
-      stereo(kDefaultStereo)
+      stereo(kDefaultStereo),
+      useInBandFec(kDefaultUseInBandFec)
     {}
 
     Parameters*
@@ -1259,12 +1261,14 @@ public:
     void
     Serialize(std::ostream& os) const override
     {
-      os << "maxplaybackrate=" << maxplaybackrate << ";"
+      os << "maxplaybackrate=" << maxplaybackrate
-         << "stereo=" << stereo;
+         << ";stereo=" << stereo
+         << ";useinbandfec=" << useInBandFec;
     }
 
     unsigned int maxplaybackrate;
     unsigned int stereo;
+    unsigned int useInBandFec;
   };
 
   class Fmtp

media/webrtc/signaling/src/sdp/SipccSdpAttributeList.cpp

@@ -726,6 +726,7 @@ SipccSdpAttributeList::LoadFmtp(sdp_t* sdp, uint16_t level)
             new SdpFmtpAttributeList::OpusParameters);
         opusParameters->maxplaybackrate = fmtp->maxplaybackrate;
         opusParameters->stereo = fmtp->stereo;
+        opusParameters->useInBandFec = fmtp->useinbandfec;
         parameters.reset(opusParameters);
       } break;
       default: {

media/webrtc/signaling/test/sdp_unittests.cpp

@@ -1561,7 +1561,7 @@ const std::string kH264AudioVideoOffer =
 "a=rtpmap:0 PCMU/8000" CRLF
 "a=rtpmap:8 PCMA/8000" CRLF
 "a=rtpmap:101 telephone-event/8000" CRLF
-"a=fmtp:109 maxplaybackrate=32000;stereo=1" CRLF
+"a=fmtp:109 maxplaybackrate=32000;stereo=1;useinbandfec=1" CRLF
 "a=ice-ufrag:00000000" CRLF
 "a=ice-pwd:0000000000000000000000000000000" CRLF
 "a=sendonly" CRLF
@@ -1623,6 +1623,7 @@ TEST_P(NewSdpTest, CheckFormatParameters) {
         audio_format_params[0].parameters.get());
   ASSERT_EQ(32000U, opus_parameters->maxplaybackrate);
   ASSERT_EQ(1U, opus_parameters->stereo);
+  ASSERT_EQ(1U, opus_parameters->useInBandFec);
 
   ASSERT_TRUE(mSdp->GetMediaSection(1).GetAttributeList().HasAttribute(
       SdpAttribute::kFmtpAttribute));

modules/libpref/init/all.js

@@ -399,7 +399,7 @@ pref("media.navigator.video.default_fps",30);
 pref("media.navigator.video.default_minfps",10);
 pref("media.navigator.video.use_remb", true);
 pref("media.navigator.video.use_tmmbr", true);
-
+pref("media.navigator.audio.use_fec", true);
 
 pref("media.webrtc.debug.trace_mask", 0);
 pref("media.webrtc.debug.multi_log", false);