Limit video senders

src/main/java/org/jitsi/impl/protocol/xmpp/ChatMemberImpl.java

@@ -94,6 +94,11 @@ public class ChatMemberImpl
      */
     private String statsId;
 
+    /**
+     * Indicates whether the member's video sources are currently muted.
+     */
+    private boolean isVideoMuted = true;
+
     public ChatMemberImpl(EntityFullJid fullJid, ChatRoomImpl chatRoom,
                           int joinOrderNumber)
     {
@@ -199,6 +204,9 @@ public boolean isJibri()
         return isJibri;
     }
 
+    @Override
+    public boolean isVideoMuted() { return isVideoMuted; }
+
     /**
      * Does presence processing.
      *
@@ -287,6 +295,19 @@ void processPresence(Presence presence)
         {
             statsId = statsIdPacketExt.getStatsId();
         }
+
+        boolean wasVideoMuted = isVideoMuted;
+        StandardExtensionElement videoMutedExt = presence.getExtension("videomuted", "jabber:client");
+        isVideoMuted = videoMutedExt == null || Boolean.valueOf(videoMutedExt.getText()); /* defaults to true */
+
+        if (isVideoMuted != wasVideoMuted)
+        {
+            logger.debug(() -> toString() + ". isMuted = " + isVideoMuted + ".");
+            if (isVideoMuted)
+                chatRoom.removeVideoSender();
+            else
+                chatRoom.addVideoSender();
+        }
     }
 
     /**

src/main/java/org/jitsi/impl/protocol/xmpp/ChatRoom.java

@@ -89,6 +89,11 @@ void join()
      */
     int getMembersCount();
 
+    /**
+     * Returns the number of members that currently have their video sources unmuted.
+     */
+    int getVideoSendersCount();
+
     /**
     * Grants ownership privileges to another user. Room owners may grant
     * ownership privileges. Some room implementations will not allow to grant

src/main/java/org/jitsi/impl/protocol/xmpp/ChatRoomImpl.java

@@ -126,6 +126,11 @@ public class ChatRoomImpl
      */
     private EventEmitter<ChatRoomListener> eventEmitter = new SyncEventEmitter<>();
 
+    /**
+     * The number of members that currently have their video sources unmuted.
+     */
+    private int numVideoSenders;
+
     /**
      * Creates new instance of <tt>ChatRoomImpl</tt>.
      *
@@ -577,6 +582,31 @@ private void sendLastPresence()
         UtilKt.tryToSendStanza(xmppProvider.getXmppConnection(), lastPresenceSent);
     }
 
+    @Override
+    public int getVideoSendersCount() { return numVideoSenders; }
+
+    public void addVideoSender()
+    {
+        ++numVideoSenders;
+        logger.debug(() -> "The number of video senders has increased to " + numVideoSenders + ".");
+
+        eventEmitter.fireEvent(handler -> {
+            handler.numVideoSendersChanged(numVideoSenders);
+            return Unit.INSTANCE;
+        });
+    }
+
+    public void removeVideoSender()
+    {
+        --numVideoSenders;
+        logger.debug(() -> "The number of video senders has decreased to " + numVideoSenders + ".");
+
+        eventEmitter.fireEvent(handler -> {
+            handler.numVideoSendersChanged(numVideoSenders);
+            return Unit.INSTANCE;
+        });
+    }
+
     /**
      * Adds a new {@link ChatMemberImpl} with the given JID to {@link #members}.
      * If a member with the given JID already exists, it returns the existing
@@ -597,6 +627,9 @@ private ChatMemberImpl addMember(EntityFullJid jid)
 
             members.put(jid, newMember);
 
+            if (!newMember.isVideoMuted())
+                addVideoSender();
+
             return newMember;
         }
     }
@@ -858,6 +891,9 @@ private ChatMemberImpl removeMember(EntityFullJid occupantJid)
                     logger.error(occupantJid + " not in " + roomJid);
                 }
 
+                if (!removed.isVideoMuted())
+                    removeVideoSender();
+
                 return removed;
             }
         }

src/main/java/org/jitsi/impl/protocol/xmpp/ChatRoomMember.java

@@ -96,6 +96,11 @@ public interface ChatRoomMember
 
     boolean isJibri();
 
+    /**
+     * Returns whether the room member has its video sources muted.
+     */
+    boolean isVideoMuted();
+
     /**
      * Gets the region (e.g. "us-east") of this {@link ChatRoomMember}.
      */

src/main/java/org/jitsi/jicofo/conference/JitsiMeetConferenceImpl.java

@@ -115,7 +115,7 @@ public class JitsiMeetConferenceImpl
     @NotNull
     private final JitsiMeetConfig config;
 
-    private final ChatRoomListener chatRoomListener = new ChatRoomListenerImpl();
+    private final ChatRoomListener chatRoomListener = new ChatRoomListenerImpl(this);
 
     /**
      * Conference room chat instance.
@@ -228,6 +228,11 @@ public class JitsiMeetConferenceImpl
      */
     private final ValidatingConferenceSourceMap conferenceSources = new ValidatingConferenceSourceMap();
 
+    /**
+     * Whether the limit on the number of video senders is currently hit.
+     */
+    private boolean videoLimitReached = false;
+
     /**
      * Creates new instance of {@link JitsiMeetConferenceImpl}.
      *
@@ -526,6 +531,19 @@ private void setConferenceProperty(String key, String value, boolean updatePrese
         }
     }
 
+    /**
+     * Process the new number of video senders reported by the chat room.
+     */
+    private void numVideoSendersChanged(int numVideoSenders)
+    {
+        boolean newValue = numVideoSenders >= ConferenceConfig.config.getMaxVideoSenders();
+        if (videoLimitReached != newValue)
+        {
+            videoLimitReached = newValue;
+            setConferenceProperty("video-limit-reached", String.valueOf(videoLimitReached));
+        }
+    }
+
     /**
      * Leaves the conference room.
      */
@@ -1504,6 +1522,14 @@ public StanzaError onAddSource(@NotNull JingleSession jingleSession, List<Conten
             return StanzaError.from(StanzaError.Condition.bad_request, e.getMessage()).build();
         }
 
+        if (sourcesAdvertised.hasVideo() &&
+            chatRoom.getVideoSendersCount() >= ConferenceConfig.config.getMaxVideoSenders())
+        {
+            String errorMsg = "Source add rejected. Maximum number of video senders reached.";
+            logger.warn(() -> participantId + ": " + errorMsg);
+            return StanzaError.from(StanzaError.Condition.resource_constraint, errorMsg).build();
+        }
+
         logger.debug(() -> "Received source-add from " + participantId + ": " + sourcesAdvertised);
         logger.debug(() -> "Accepted sources from " + participantId + ": " + sourcesAccepted);
 
@@ -2417,6 +2443,12 @@ public void bridgeAdded(Bridge bridge)
 
     private class ChatRoomListenerImpl implements ChatRoomListener
     {
+        private final JitsiMeetConferenceImpl conference;
+        private ChatRoomListenerImpl(JitsiMeetConferenceImpl conference)
+        {
+            this.conference = conference;
+        }
+
         @Override
         public void roomDestroyed(@NotNull String reason)
         {
@@ -2463,5 +2495,11 @@ public void localRoleChanged(@NotNull MemberRole newRole, @Nullable MemberRole o
         public void memberPresenceChanged(@NotNull ChatRoomMember member)
         {
         }
+
+        @Override
+        public void numVideoSendersChanged(int numVideoSenders)
+        {
+            conference.numVideoSendersChanged(numVideoSenders);
+        }
     }
 }

src/main/kotlin/org/jitsi/jicofo/ConferenceConfig.kt

@@ -62,6 +62,10 @@ class ConferenceConfig {
         "jicofo.conference.min-participants".from(newConfig)
     }
 
+    val maxVideoSenders: Int by config {
+        "jicofo.conference.max-video-senders".from(newConfig)
+    }
+
     val enableLipSync: Boolean by config {
         "jicofo.conference.enable-lip-sync".from(newConfig)
     }

src/main/kotlin/org/jitsi/jicofo/conference/source/EndpointSourceSet.kt

@@ -41,6 +41,16 @@ data class EndpointSourceSet(
      */
     fun isEmpty() = sources.isEmpty() && ssrcGroups.isEmpty()
 
+    /**
+     * Whether there are any audio sources in this set.
+     */
+    fun hasAudio() = sources.any { it.mediaType == AUDIO }
+
+    /**
+     * Whether there are any video sources in this set.
+     */
+    fun hasVideo() = sources.any { it.mediaType == VIDEO }
+
     /**
      * Creates a list of Jingle [ContentPacketExtension]s that describe the sources in this [EndpointSourceSet].
      */

src/main/kotlin/org/jitsi/jicofo/xmpp/muc/ChatRoomListener.kt

@@ -29,6 +29,7 @@ interface ChatRoomListener {
     fun roomDestroyed(reason: String) {}
     fun startMutedChanged(startAudioMuted: Boolean, startVideoMuted: Boolean) {}
     fun localRoleChanged(newRole: MemberRole, oldRole: MemberRole? = null) {}
+    fun numVideoSendersChanged(numVideoSenders: Int) {}
 }
 
 /** A class with the default kotlin method implementations (to avoid using @JvmDefault) **/

src/main/resources/reference.conf

@@ -177,6 +177,9 @@ jicofo {
     // The minimum number of participants required for the conference to be started.
     min-participants = 2
 
+    // The maximum number of participants that can send their video at the same time.
+    max-video-senders = 50
+
     // Experimental.
     enable-lip-sync = false