/**
* Ctor.
*
* @param videoChannel The <tt>VideoChannel</tt> associated to this <tt>SimulcastEngine</tt>.
*/
public SimulcastEngine(VideoChannel videoChannel) {
this.videoChannel = videoChannel;
simulcastReceiver =
new SimulcastReceiver(
this,
ServiceUtils.getService(videoChannel.getBundleContext(), ConfigurationService.class));
this.logger =
Logger.getLogger(classLogger, videoChannel.getContent().getConference().getLogger());
}
/**
* Initializes the local list of endpoints ({@link #speechActivityEndpointsChanged(List)}) with
* the current endpoints from the conference.
*/
public synchronized void initializeConferenceEndpoints() {
speechActivityEndpointsChanged(channel.getConferenceSpeechActivity().getEndpoints());
if (logger.isDebugEnabled()) {
logger.debug(
"Initialized the list of endpoints: " + conferenceSpeechActivityEndpoints.toString());
}
}
/** @return the ID of the endpoint of our channel. */
private String getEndpointId() {
if (endpointId == null) {
Endpoint endpoint = channel.getEndpoint();
if (endpoint != null) {
endpointId = endpoint.getID();
}
}
return endpointId;
}
/**
* Sends a keyframe request to the endpoints specified in {@code endpointIds}
*
* @param endpointIds the list of IDs of endpoints to which to send a request for a keyframe.
*/
private void askForKeyframes(List<String> endpointIds) {
// TODO: Execute asynchronously.
if (endpointIds != null && !endpointIds.isEmpty()) {
channel.getContent().askForKeyframesById(endpointIds);
}
}
/**
* Recalculates the list of forwarded endpoints based on the current values of the various
* parameters of this instance ({@link #lastN}, {@link #conferenceSpeechActivityEndpoints}, {@link
* #pinnedEndpoints}).
*
* @param newConferenceEndpoints A list of endpoints which entered the conference since the last
* call to this method. They need not be asked for keyframes, because they were never filtered
* by this {@link #LastNController(VideoChannel)}.
* @return the list of IDs of endpoints which were added to {@link #forwardedEndpoints} (i.e. of
* endpoints * "entering last-n") as a result of this call. Returns {@code null} if no
* endpoints were added.
*/
private synchronized List<String> update(List<String> newConferenceEndpoints) {
List<String> newForwardedEndpoints = new LinkedList<>();
String ourEndpointId = getEndpointId();
if (conferenceSpeechActivityEndpoints == INITIAL_EMPTY_LIST) {
conferenceSpeechActivityEndpoints =
getIDs(channel.getConferenceSpeechActivity().getEndpoints());
newConferenceEndpoints = conferenceSpeechActivityEndpoints;
}
if (lastN < 0 && currentLastN < 0) {
// Last-N is disabled, we forward everything.
newForwardedEndpoints.addAll(conferenceSpeechActivityEndpoints);
if (ourEndpointId != null) {
newForwardedEndpoints.remove(ourEndpointId);
}
} else {
// Here we have lastN >= 0 || currentLastN >= 0 which implies
// currentLastN >= 0.
// Pinned endpoints are always forwarded.
newForwardedEndpoints.addAll(getPinnedEndpoints());
// As long as they are still endpoints in the conference.
newForwardedEndpoints.retainAll(conferenceSpeechActivityEndpoints);
if (newForwardedEndpoints.size() > currentLastN) {
// What do we want in this case? It looks like a contradictory
// request from the client, but maybe it makes for a good API
// on the client to allow the pinned to override last-n.
// Unfortunately, this will not play well with Adaptive-Last-N
// or changes to Last-N for other reasons.
} else if (newForwardedEndpoints.size() < currentLastN) {
for (String endpointId : conferenceSpeechActivityEndpoints) {
if (newForwardedEndpoints.size() < currentLastN) {
if (!endpointId.equals(ourEndpointId) && !newForwardedEndpoints.contains(endpointId)) {
newForwardedEndpoints.add(endpointId);
}
} else {
break;
}
}
}
}
List<String> enteringEndpoints;
if (forwardedEndpoints.equals(newForwardedEndpoints)) {
// We want forwardedEndpoints != INITIAL_EMPTY_LIST
forwardedEndpoints = newForwardedEndpoints;
enteringEndpoints = null;
} else {
enteringEndpoints = new ArrayList<>(newForwardedEndpoints);
enteringEndpoints.removeAll(forwardedEndpoints);
if (logger.isDebugEnabled()) {
logger.debug(
"Forwarded endpoints changed: "
+ forwardedEndpoints.toString()
+ " -> "
+ newForwardedEndpoints.toString()
+ ". Entering: "
+ enteringEndpoints.toString());
}
forwardedEndpoints = Collections.unmodifiableList(newForwardedEndpoints);
if (lastN >= 0 || currentLastN >= 0) {
// TODO: we may want to do this asynchronously.
channel.sendLastNEndpointsChangeEventOnDataChannel(forwardedEndpoints, enteringEndpoints);
}
}
// If lastN is disabled, the endpoints entering forwardedEndpoints were
// never filtered, so they don't need to be asked for keyframes.
if (lastN < 0 && currentLastN < 0) {
enteringEndpoints = null;
}
if (enteringEndpoints != null && newConferenceEndpoints != null) {
// Endpoints just entering the conference need not be asked for
// keyframes.
enteringEndpoints.removeAll(newConferenceEndpoints);
}
return enteringEndpoints;
}