Merge pull request #302 from stefanholmer/master

Add support for GET parameter to disable video FEC.

src/web_app/html/params.html

@@ -83,6 +83,7 @@ <h1>AppRTC parameters</h1>
         <tr><td><a href="https://appr.tc?asbr=16000">asbr=[bitrate]</a></td><td>Set audio send bitrate</td></tr>
         <tr><td><a href="https://appr.tc?vsbr=1000">vsbr=[bitrate]</a></td><td>Set video receive bitrate</td></tr>
         <tr><td><a href="https://appr.tc?vrbr=8000">vrbr=[bitrate]</a></td><td>Set video send bitrate</td></tr>
+        <tr><td><a href="https://appr.tc?videofec=false">videofec=false</a></td><td>Turn off video FEC</td></tr>
         <tr><td><a href="https://appr.tc?opusfec=false">opusfec=false</a></td><td>Turn off Opus FEC</td></tr>
         <tr><td><a href="https://appr.tc?opusdtx=true">opusdtx=true</a></td><td>Turn on Opus DTX</td></tr>
         <tr><td><a href="https://appr.tc?opusmaxpbr=8000">opusmaxpbr=8000</a></td><td>Set the maximum sample rate that the receiver can operate, for optimal Opus encoding performance</td></tr>

src/web_app/js/appcontroller.js

@@ -551,6 +551,7 @@ AppController.prototype.loadUrlParams_ = function() {
   this.loadingParams_.videoSendCodec = urlParams['vsc'];
   this.loadingParams_.videoRecvBitrate = urlParams['vrbr'];
   this.loadingParams_.videoRecvCodec = urlParams['vrc'] || DEFAULT_VIDEO_CODEC;
+  this.loadingParams_.videoFec = urlParams['videofec'];
   /* jshint ignore:end */
   /* jscs: enable */
 };

src/web_app/js/peerconnectionclient.js

@@ -14,7 +14,7 @@
    maybeSetAudioSendBitRate, maybeSetVideoSendBitRate,
    maybeSetAudioReceiveBitRate, maybeSetVideoSendInitialBitRate,
    maybeSetVideoReceiveBitRate, maybeSetVideoSendInitialBitRate,
-   maybeSetOpusOptions */
+   maybeRemoveVideoFec, maybeSetOpusOptions */
 
 /* exported PeerConnectionClient */
 
@@ -213,6 +213,7 @@ PeerConnectionClient.prototype.setRemoteSdp_ = function(message) {
   message.sdp = maybeSetAudioSendBitRate(message.sdp, this.params_);
   message.sdp = maybeSetVideoSendBitRate(message.sdp, this.params_);
   message.sdp = maybeSetVideoSendInitialBitRate(message.sdp, this.params_);
+  message.sdp = maybeRemoveVideoFec(message.sdp);
   this.pc_.setRemoteDescription(new RTCSessionDescription(message))
   .then(this.onSetRemoteDescriptionSuccess_.bind(this))
   .catch(this.onError_.bind(this, 'setRemoteDescription'));

src/web_app/js/sdputils.js

@@ -15,7 +15,7 @@
    maybeSetAudioSendBitRate, maybePreferVideoReceiveCodec,
    maybePreferVideoSendCodec, maybeSetVideoReceiveBitRate,
    maybeSetVideoSendBitRate, maybeSetVideoSendInitialBitRate,
-   mergeConstraints, removeCodecParam*/
+   maybeRemoveVideoFec, mergeConstraints, removeCodecParam*/
 
 'use strict';
 
@@ -202,6 +202,79 @@ function maybeSetVideoSendInitialBitRate(sdp, params) {
   return sdp;
 }
 
+function removePayloadTypeFromMline(mLine, payloadType) {
+  mLine = mLine.split(' ');
+  for (var i = 0; i < mLine.length; ++i) {
+    if (mLine[i] === payloadType.toString()) {
+      mLine.splice(i, 1);
+    }
+  }
+  return mLine.join(' ');
+}
+
+function removeCodecByName(sdpLines, codec) {
+  var index = findLine(sdpLines, 'a=rtpmap', codec);
+  if (index === null) {
+    return sdpLines;
+  }
+  var payloadType = getCodecPayloadTypeFromLine(sdpLines[index]);
+  sdpLines.splice(index, 1);
+
+  // Search for the video m= line and remove the codec.
+  var mLineIndex = findLine(sdpLines, 'm=', 'video');
+  if (mLineIndex === null) {
+    return sdpLines;
+  }
+  sdpLines[mLineIndex] = removePayloadTypeFromMline(sdpLines[mLineIndex],
+    payloadType);
+  return sdpLines;
+}
+
+function removeCodecByPayloadType(sdpLines, payloadType) {
+  var index = findLine(sdpLines, 'a=rtpmap', payloadType.toString());
+  if (index === null) {
+    return sdpLines;
+  }
+  sdpLines.splice(index, 1);
+
+  // Search for the video m= line and remove the codec.
+  var mLineIndex = findLine(sdpLines, 'm=', 'video');
+  if (mLineIndex === null) {
+    return sdpLines;
+  }
+  sdpLines[mLineIndex] = removePayloadTypeFromMline(sdpLines[mLineIndex],
+    payloadType);
+  return sdpLines;
+}
+
+function maybeRemoveVideoFec(sdp) {
+  var sdpLines = sdp.split('\r\n');
+
+  var index = findLine(sdpLines, 'a=rtpmap', 'red');
+  if (index === null) {
+    return sdp;
+  }
+  var redPayloadType = getCodecPayloadTypeFromLine(sdpLines[index]);
+  sdpLines = removeCodecByPayloadType(sdpLines, redPayloadType);
+
+  sdpLines = removeCodecByName(sdpLines, 'ulpfec');
+
+  // Remove fmtp lines associated with red codec.
+  index = findLine(sdpLines, 'a=fmtp', redPayloadType.toString());
+  if (index === null) {
+    return sdp;
+  }
+  var fmtpLine = parseFmtpLine(sdpLines[index]);
+  var rtxPayloadType = fmtpLine.pt;
+  if (rtxPayloadType === null) {
+    return sdp;
+  }
+  sdpLines.splice(index, 1);
+
+  sdpLines = removeCodecByPayloadType(sdpLines, rtxPayloadType);
+  return sdpLines.join('\r\n');
+}
+
 // Promotes |audioSendCodec| to be the first in the m=audio line, if set.
 function maybePreferAudioSendCodec(sdp, params) {
   return maybePreferCodec(sdp, 'audio', 'send', params.audioSendCodec);