Adds RTP stats processing.

app.js

@@ -8,6 +8,11 @@ var nickname = null;
 var sharedKey = '';
 var roomUrl = null;
 var ssrc2jid = {};
+/**
+ * The stats collector that process stats data and triggers updates to app.js.
+ * @type {StatsCollector}
+ */
+var statsCollector = null;
 
 /**
  * Indicates whether ssrc is camera video or desktop stream.
@@ -464,12 +469,46 @@ function muteVideo(pc, unmute) {
     );
 }
 
+/**
+ * Callback called by {@link StatsCollector} in intervals supplied to it's
+ * constructor.
+ * @param statsCollector {@link StatsCollector} source of the event.
+ */
+function statsUpdated(statsCollector)
+{
+    Object.keys(statsCollector.jid2stats).forEach(function (jid)
+    {
+        var peerStats = statsCollector.jid2stats[jid];
+        Object.keys(peerStats.ssrc2AudioLevel).forEach(function (ssrc)
+        {
+            console.info(jid +  " audio level: " +
+                peerStats.ssrc2AudioLevel[ssrc] + " of ssrc: " + ssrc);
+        });
+    });
+}
+
+/**
+ * Starts the {@link StatsCollector} if the feature is enabled in config.js.
+ */
+function startRtpStatsCollector()
+{
+    if (config.enableRtpStats)
+    {
+        statsCollector = new StatsCollector(
+            getConferenceHandler().peerconnection, 200, statsUpdated);
+
+        statsCollector.start();
+    }
+}
+
 $(document).bind('callincoming.jingle', function (event, sid) {
     var sess = connection.jingle.sessions[sid];
 
     // TODO: do we check activecall == null?
     activecall = sess;
 
+    startRtpStatsCollector();
+
     // TODO: check affiliation and/or role
     console.log('emuc data for', sess.peerjid, connection.emuc.members[sess.peerjid]);
     sess.usedrip = true; // not-so-naive trickle ice
@@ -478,6 +517,11 @@ $(document).bind('callincoming.jingle', function (event, sid) {
 
 });
 
+$(document).bind('conferenceCreated.jingle', function (event, focus)
+{
+    startRtpStatsCollector();
+});
+
 $(document).bind('callactive.jingle', function (event, videoelem, sid) {
     if (videoelem.attr('id').indexOf('mixedmslabel') === -1) {
         // ignore mixedmslabela0 and v0
@@ -1165,6 +1209,11 @@ function disposeConference() {
         }
         handler.peerconnection.close();
     }
+    if (statsCollector)
+    {
+        statsCollector.stop();
+        statsCollector = null;
+    }
     focus = null;
     activecall = null;
 }

config.js

@@ -11,5 +11,6 @@ var config = {
     bosh: '//lambada.jitsi.net/http-bind', // FIXME: use xep-0156 for that
     desktopSharing: 'ext', // Desktop sharing method. Can be set to 'ext', 'webrtc' or false to disable.
     chromeExtensionId: 'diibjkoicjeejcmhdnailmkgecihlobk', // Id of desktop streamer Chrome extension
-    minChromeExtVersion: '0.1' // Required version of Chrome extension
+    minChromeExtVersion: '0.1', // Required version of Chrome extension
+    enableRtpStats: false // Enables RTP stats processing
 };

index.html

@@ -33,6 +33,7 @@
     <script src="replacement.js?v=5"></script><!-- link and smiley replacement -->
     <script src="moderatemuc.js?v=1"></script><!-- moderator plugin -->
     <script src="analytics.js?v=1"></script><!-- google analytics plugin -->
+    <script src="rtp_stats.js?v=1"></script><!-- RTP stats processing -->
     <link href="//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css" rel="stylesheet">
     <link rel="stylesheet" href="css/font.css"/>
     <link rel="stylesheet" type="text/css" media="screen" href="css/main.css?v=20"/>

libs/colibri/colibri.focus.js

@@ -344,6 +344,10 @@ ColibriFocus.prototype.createdConference = function (result) {
                             for (var i = 0; i < numparticipants; i++) {
                                 self.initiate(self.peers[i], true);
                             }
+
+                            // Notify we've created the conference
+                            $(document).trigger(
+                                'conferenceCreated.jingle', self);
                         },
                         function (error) {
                             console.warn('setLocalDescription failed.', error);

libs/strophe/strophe.jingle.adapter.js

@@ -5,7 +5,7 @@ function TraceablePeerConnection(ice_config, constraints) {
     this.updateLog = [];
     this.stats = {};
     this.statsinterval = null;
-    this.maxstats = 300; // limit to 300 values, i.e. 5 minutes; set to 0 to disable
+    this.maxstats = 0; // limit to 300 values, i.e. 5 minutes; set to 0 to disable
 
     /**
      * Array of ssrcs that will be added on next modifySources call.
@@ -88,8 +88,8 @@ function TraceablePeerConnection(ice_config, constraints) {
         if (self.ondatachannel !== null) {
             self.ondatachannel(event);
         }
-    }
+    };
-    if (!navigator.mozGetUserMedia) {
+    if (!navigator.mozGetUserMedia && this.maxstats) {
         this.statsinterval = window.setInterval(function() {
             self.peerconnection.getStats(function(stats) {
                 var results = stats.result();

rtp_stats.js

@@ -0,0 +1,287 @@
+/* global ssrc2jid */
+
+/**
+ * Function object which once created can be used to calculate moving average of
+ * given period. Example for SMA3:</br>
+ * var sma3 = new SimpleMovingAverager(3);
+ * while(true) // some update loop
+ * {
+ *   var currentSma3Value = sma3(nextInputValue);
+ * }
+ *
+ * @param period moving average period that will be used by created instance.
+ * @returns {Function} SMA calculator function of given <tt>period</tt>.
+ * @constructor
+ */
+function SimpleMovingAverager(period)
+{
+    var nums = [];
+    return function (num)
+    {
+        nums.push(num);
+        if (nums.length > period)
+            nums.splice(0, 1);
+        var sum = 0;
+        for (var i in nums)
+            sum += nums[i];
+        var n = period;
+        if (nums.length < period)
+            n = nums.length;
+        return (sum / n);
+    };
+}
+
+/**
+ * Peer statistics data holder.
+ * @constructor
+ */
+function PeerStats()
+{
+    this.ssrc2Loss = {};
+    this.ssrc2AudioLevel = {};
+}
+
+/**
+ * Sets packets loss rate for given <tt>ssrc</tt> that blong to the peer
+ * represented by this instance.
+ * @param ssrc audio or video RTP stream SSRC.
+ * @param lossRate new packet loss rate value to be set.
+ */
+PeerStats.prototype.setSsrcLoss = function (ssrc, lossRate)
+{
+    this.ssrc2Loss[ssrc] = lossRate;
+};
+
+/**
+ * Sets new audio level(input or output) for given <tt>ssrc</tt> that identifies
+ * the stream which belongs to the peer represented by this instance.
+ * @param ssrc RTP stream SSRC for which current audio level value will be
+ *        updated.
+ * @param audioLevel the new audio level value to be set. Value is truncated to
+ *        fit the range from 0 to 1.
+ */
+PeerStats.prototype.setSsrcAudioLevel = function (ssrc, audioLevel)
+{
+    // Range limit 0 - 1
+    this.ssrc2AudioLevel[ssrc] = Math.min(Math.max(audioLevel, 0), 1);
+};
+
+/**
+ * Calculates average packet loss for all streams that belong to the peer
+ * represented by this instance.
+ * @returns {number} average packet loss for all streams that belong to the peer
+ *                   represented by this instance.
+ */
+PeerStats.prototype.getAvgLoss = function ()
+{
+    var self = this;
+    var avg = 0;
+    var count = Object.keys(this.ssrc2Loss).length;
+    Object.keys(this.ssrc2Loss).forEach(
+        function (ssrc)
+        {
+            avg += self.ssrc2Loss[ssrc];
+        }
+    );
+    return count > 0 ? avg / count : 0;
+};
+
+/**
+ * <tt>StatsCollector</tt> registers for stats updates of given
+ * <tt>peerconnection</tt> in given <tt>interval</tt>. On each update particular
+ * stats are extracted and put in {@link PeerStats} objects. Once the processing
+ * is done <tt>updateCallback</tt> is called with <tt>this</tt> instance as
+ * an event source.
+ *
+ * @param peerconnection webRTC peer connection object.
+ * @param interval stats refresh interval given in ms.
+ * @param {function(StatsCollector)} updateCallback the callback called on stats
+ *                                   update.
+ * @constructor
+ */
+function StatsCollector(peerconnection, interval, updateCallback)
+{
+    this.peerconnection = peerconnection;
+    this.baselineReport = null;
+    this.currentReport = null;
+    this.intervalId = null;
+    // Updates stats interval
+    this.intervalMilis = interval;
+    // Use SMA 3 to average packet loss changes over time
+    this.sma3 = new SimpleMovingAverager(3);
+    // Map of jids to PeerStats
+    this.jid2stats = {};
+
+    this.updateCallback = updateCallback;
+}
+
+/**
+ * Stops stats updates.
+ */
+StatsCollector.prototype.stop = function ()
+{
+    if (this.intervalId)
+    {
+        clearInterval(this.intervalId);
+        this.intervalId = null;
+    }
+};
+
+/**
+ * Callback passed to <tt>getStats</tt> method.
+ * @param error an error that occurred on <tt>getStats</tt> call.
+ */
+StatsCollector.prototype.errorCallback = function (error)
+{
+    console.error("Get stats error", error);
+    this.stop();
+};
+
+/**
+ * Starts stats updates.
+ */
+StatsCollector.prototype.start = function ()
+{
+    var self = this;
+    this.intervalId = setInterval(
+        function ()
+        {
+            // Interval updates
+            self.peerconnection.getStats(
+                function (report)
+                {
+                    var results = report.result();
+                    //console.error("Got interval report", results);
+                    self.currentReport = results;
+                    self.processReport();
+                    self.baselineReport = self.currentReport;
+                },
+                self.errorCallback
+            );
+        },
+        self.intervalMilis
+    );
+};
+
+/**
+ * Stats processing logic.
+ */
+StatsCollector.prototype.processReport = function ()
+{
+    if (!this.baselineReport)
+    {
+        return;
+    }
+
+    for (var idx in this.currentReport)
+    {
+        var now = this.currentReport[idx];
+        if (now.type != 'ssrc')
+        {
+            continue;
+        }
+
+        var before = this.baselineReport[idx];
+        if (!before)
+        {
+            console.warn(now.stat('ssrc') + ' not enough data');
+            continue;
+        }
+
+        var ssrc = now.stat('ssrc');
+        var jid = ssrc2jid[ssrc];
+        if (!jid)
+        {
+            console.warn("No jid for ssrc: " + ssrc);
+            continue;
+        }
+
+        var jidStats = this.jid2stats[jid];
+        if (!jidStats)
+        {
+            jidStats = new PeerStats();
+            this.jid2stats[jid] = jidStats;
+        }
+
+        // Audio level
+        var audioLevel = now.stat('audioInputLevel');
+        if (!audioLevel)
+            audioLevel = now.stat('audioOutputLevel');
+        if (audioLevel)
+        {
+            // TODO: can't find specs about what this value really is,
+            // but it seems to vary between 0 and around 32k.
+            audioLevel = audioLevel / 32767;
+            jidStats.setSsrcAudioLevel(ssrc, audioLevel);
+        }
+
+        var key = 'packetsReceived';
+        if (!now.stat(key))
+        {
+            key = 'packetsSent';
+            if (!now.stat(key))
+            {
+                console.error("No packetsReceived nor packetSent stat found");
+                this.stop();
+                return;
+            }
+        }
+        var packetsNow = now.stat(key);
+        var packetsBefore = before.stat(key);
+        var packetRate = packetsNow - packetsBefore;
+
+        var currentLoss = now.stat('packetsLost');
+        var previousLoss = before.stat('packetsLost');
+        var lossRate = currentLoss - previousLoss;
+
+        var packetsTotal = (packetRate + lossRate);
+        var lossPercent;
+
+        if (packetsTotal > 0)
+            lossPercent = lossRate / packetsTotal;
+        else
+            lossPercent = 0;
+
+        //console.info(jid + " ssrc: " + ssrc + " " + key + ": " + packetsNow);
+
+        jidStats.setSsrcLoss(ssrc, lossPercent);
+    }
+
+    var self = this;
+    // Jid stats
+    var allPeersAvg = 0;
+    var jids = Object.keys(this.jid2stats);
+    jids.forEach(
+        function (jid)
+        {
+            var peerAvg = self.jid2stats[jid].getAvgLoss(
+                function (avg)
+                {
+                    //console.info(jid + " stats: " + (avg * 100) + " %");
+                    allPeersAvg += avg;
+                }
+            );
+        }
+    );
+
+    if (jids.length > 1)
+    {
+        // Our streams loss is reported as 0 always, so -1 to length
+        allPeersAvg = allPeersAvg / (jids.length - 1);
+
+        /**
+         * Calculates number of connection quality bars from 4(hi) to 0(lo).
+         */
+        var outputAvg = self.sma3(allPeersAvg);
+        // Linear from 4(0%) to 0(25%).
+        var quality = Math.round(4 - outputAvg * 16);
+        quality = Math.max(quality, 0); // lower limit 0
+        quality = Math.min(quality, 4); // upper limit 4
+        // TODO: quality can be used to indicate connection quality using 4 step
+        // bar indicator
+        //console.info("Loss SMA3: " + outputAvg + " Q: " + quality);
+    }
+
+    self.updateCallback(self);
+};
+