--- a/src/jlibrtp/RTCPSession.java Thu May 28 14:26:06 2009 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,527 +0,0 @@
-/**
- * Java RTP Library (jlibrtp)
- * Copyright (C) 2006 Arne Kepp
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-package jlibrtp;
-
-import java.util.Enumeration;
-import java.net.DatagramSocket;
-import java.net.InetAddress;
-import java.net.MulticastSocket;
-import java.util.LinkedList;
-import java.util.Hashtable;
-import java.util.ListIterator;
-import java.util.Arrays;
-
-
-/**
- * This class acts as an organizer for most of the information
- * and functions pertaining to RTCP packet generation and reception
- *
- * @author Arne Kepp
- *
- */
-public class RTCPSession {
- /** Parent session */
- protected RTPSession rtpSession = null;
-
- /** Unicast socket */
- protected DatagramSocket rtcpSock = null;
- /** Multicast socket */
- protected MulticastSocket rtcpMCSock = null;
- /** Multicast group */
- protected InetAddress mcGroup = null;
-
- /** RTCP Receiver thread */
- protected RTCPReceiverThread recvThrd = null;
- /** RTCP Sender thread */
- protected RTCPSenderThread senderThrd = null;
-
- /** Previous time a delay was calculated */
- protected long prevTime = System.currentTimeMillis();
- /** Delay between RTCP transmissions, in ms. Initialized in start() */
- protected int nextDelay = -1; //
- /** The average compound RTCP packet size, in octets, including UDP and IP headers */
- protected int avgPktSize = 200; //
- /** Pessimistic case estimate of the current number of senders */
- protected int senderCount = 1;
- /** Whether next RTCP packet can be sent early */
- protected boolean fbAllowEarly = false;
- /** Feedback queue , index is SSRC of target */
- protected Hashtable<Long, LinkedList<RtcpPkt>> fbQueue = null;
- /** APP queue , index is SSRC of target */
- protected Hashtable<Long, LinkedList<RtcpPktAPP>> appQueue = null;
- /** Are we just starting up? */
- protected boolean initial = true;
- /** Is there a feedback packet waiting? SSRC of destination */
- protected long fbWaiting = -1;
-
- /**
- * Constructor for unicast sessions
- *
- * @param parent RTPSession that started this
- * @param rtcpSocket the socket to use for listening and sending
- */
- protected RTCPSession(RTPSession parent, DatagramSocket rtcpSocket) {
- this.rtcpSock = rtcpSocket;
- rtpSession = parent;
- }
-
- /**
- * Constructor for multicast sessions
- *
- * @param parent parent RTPSession
- * @param rtcpSocket parent RTPSession that started this
- * @param multicastGroup multicast group to bind the socket to
- */
- protected RTCPSession(RTPSession parent, MulticastSocket rtcpSocket, InetAddress multicastGroup) {
- mcGroup = multicastGroup;
- this.rtcpSock = rtcpSocket;
- rtpSession = parent;
- }
-
- /**
- * Starts the session, calculates delays and fires up the threads.
- *
- */
- protected void start() {
- //nextDelay = 2500 + rtpSession.random.nextInt(1000) - 500;
- this.calculateDelay();
- recvThrd = new RTCPReceiverThread(this, this.rtpSession);
- senderThrd = new RTCPSenderThread(this, this.rtpSession);
- recvThrd.start();
- senderThrd.start();
- }
-
- /**
- * Send bye packets, handled by RTCP Sender thread
- *
- */
- protected void sendByes() {
- senderThrd.sendByes();
- }
-
- /**
- * Calculate the delay before the next RTCP packet can be sent
- *
- */
- protected void calculateDelay() {
- switch(rtpSession.rtcpMode) {
- case 0: calculateRegularDelay(); break;
- default:
- System.out.println("RTCPSession.calculateDelay() unknown .mode");
- }
- }
-
- /**
- * Calculates a delay value in accordance with RFC 3550
- *
- */
- protected void calculateRegularDelay() {
- long curTime = System.currentTimeMillis();
-
- if(rtpSession.bandwidth != 0 && ! this.initial && rtpSession.partDb.ssrcTable.size() > 4) {
- // RTPs mechanisms for RTCP scalability
- int rand = rtpSession.random.nextInt(10000) - 5000; //between -500 and +500
- double randDouble = ((double) 1000 + rand)/1000.0;
-
-
- Enumeration<Participant> enu = rtpSession.partDb.getParticipants();
- while(enu.hasMoreElements()) {
- Participant part = enu.nextElement();
- if(part.lastRtpPkt > this.prevTime)
- senderCount++;
- }
-
- double bw;
- if(rtpSession.rtcpBandwidth > -1) {
- bw = rtpSession.rtcpBandwidth;
- }else {
- bw = rtpSession.bandwidth*0.05;
- }
- if(senderCount*2 > rtpSession.partDb.ssrcTable.size()) {
- if(rtpSession.lastTimestamp > this.prevTime) {
- //We're a sender
- double numerator = ((double) this.avgPktSize)*((double) senderCount);
- double denominator = 0.25*bw;
- this.nextDelay = (int) Math.round((numerator/denominator)*randDouble);
- } else {
- //We're a receiver
- double numerator = ((double) this.avgPktSize)*((double) rtpSession.partDb.ssrcTable.size());
- double denominator = 0.75*bw;
- this.nextDelay = (int) Math.round((numerator/denominator)*randDouble);
- }
- } else {
- double numerator = ((double) this.avgPktSize)*((double) rtpSession.partDb.ssrcTable.size());;
- double denominator = bw;
- this.nextDelay = (int) Math.round(1000.0*(numerator/denominator)) * (1000 + rand);
- }
- } else {
- // Not enough data to scale, use random values
- int rand = rtpSession.random.nextInt(1000) - 500; //between -500 and +500
- if(this.initial) {
- // 2.5 to 3.5 seconds, randomly
- this.nextDelay = 3000 + rand;
- this.initial = false;
- } else {
- // 4.5 to 5.5 seconds, randomly
- this.nextDelay = 5500 + rand;
- }
-
- }
-
- // preflight check
- if(this.nextDelay < 1000) {
- int rand = rtpSession.random.nextInt(1000) - 500; //between -500 and +500
- System.out.println("RTCPSession.calculateDelay() nextDelay was too short ("
- +this.nextDelay+"ms), setting to "+(this.nextDelay = 2000 + rand));
- }
- this.prevTime = curTime;
- }
-
- /**
- * Update the average packet size
- * @param length of latest packet
- */
- synchronized protected void updateAvgPacket(int length) {
- double tempAvg = (double) this.avgPktSize;
- tempAvg = (15*tempAvg + ((double) length))/16;
- this.avgPktSize = (int) tempAvg;
- }
-
-
- /**
- * Adds an RTCP APP (application) packet to the queue
- *
- * @param targetSsrc the SSRC of the recipient
- * @param aPkt
- */
- synchronized protected void addToAppQueue(long targetSsrc, RtcpPktAPP aPkt) {
- aPkt.time = System.currentTimeMillis();
-
- if(this.appQueue == null)
- this.appQueue = new Hashtable<Long, LinkedList<RtcpPktAPP>>();
-
- LinkedList<RtcpPktAPP> ll = this.appQueue.get(targetSsrc);
- if(ll == null) {
- // No list, create and add
- ll = new LinkedList<RtcpPktAPP>();
- this.appQueue.put(targetSsrc, ll);
- }
-
- ll.add(aPkt);
- }
-
-
- /**
- * Adds an RTCP APP (application) packet to the queue
- *
- * @param targetSsrc the SSRC of the recipient
- * @return array of RTCP Application packets
- */
- synchronized protected RtcpPktAPP[] getFromAppQueue(long targetSsrc) {
- if(this.appQueue == null)
- return null;
-
- LinkedList<RtcpPktAPP> ll = this.appQueue.get(targetSsrc);
- if(ll == null || ll.isEmpty()) {
- return null;
- } else {
- RtcpPktAPP[] ret = new RtcpPktAPP[ll.size()];
- ListIterator<RtcpPktAPP> li = ll.listIterator();
- int i = 0;
- while(li.hasNext()) {
- ret[i] = li.next();
- i++;
- }
- return ret;
- }
- }
-
-
- /**
- * Cleans the TCP APP (application) packet queues of any packets that are
- * too old, defined as 60 seconds since insertion.
- *
- * @param ssrc The SSRC of the user who has left, negative value -> general cleanup
- */
- synchronized protected void cleanAppQueue(long ssrc) {
- if(this.appQueue == null)
- return;
-
- if(ssrc > 0) {
- this.appQueue.remove(ssrc);
- } else {
- Enumeration<LinkedList<RtcpPktAPP>> enu = this.appQueue.elements();
- long curTime = System.currentTimeMillis();
-
-
- while(enu.hasMoreElements()) {
- ListIterator<RtcpPktAPP> li = enu.nextElement().listIterator();
- while(li.hasNext()) {
- RtcpPkt aPkt = li.next();
- //Remove after 60 seconds
- if(curTime - aPkt.time > 60000) {
- li.remove();
- }
- }
- }
- }
- }
-
-
-
- /**
- * Check the feedback queue for similar packets and adds
- * the new packet if it is not redundant
- *
- * @param aPkt
- * @return 0 if the packet was added, 1 if it was dropped
- */
- synchronized protected int addToFbQueue(long targetSsrc, RtcpPkt aPkt) {
- if(this.fbQueue == null)
- this.fbQueue = new Hashtable<Long, LinkedList<RtcpPkt>>();
-
- LinkedList<RtcpPkt> ll = this.fbQueue.get(targetSsrc);
- if(ll == null) {
- // No list, create and add
- ll = new LinkedList<RtcpPkt>();
- ll.add(aPkt);
- this.fbQueue.put(targetSsrc, ll);
- } else {
- // Check for matching packets, else add to end
- ListIterator<RtcpPkt> li = ll.listIterator();
- while(li.hasNext()) {
- RtcpPkt tmp = li.next();
- if(equivalent(tmp, aPkt))
- return -1;
- }
- ll.addLast(aPkt);
- }
- return 0;
- }
-
- /**
- * Checks whether there are ny feedback packets waiting
- * to be sent.
- *
- * @param ssrc of the participant we are notifying
- * @return all relevant feedback packets, or null
- */
- synchronized protected RtcpPkt[] getFromFbQueue(long ssrc) {
- if(this.fbQueue == null)
- return null;
-
- LinkedList<RtcpPkt> ll = this.fbQueue.get(ssrc);
-
- if(ll == null)
- return null;
-
- ListIterator<RtcpPkt> li = ll.listIterator();
- if(li.hasNext()) {
- long curTime = System.currentTimeMillis();
- long maxDelay = curTime - rtpSession.fbMaxDelay;
- long keepDelay = curTime - 2000;
- int count = 0;
-
- //TODO below the indeces should be collected instead of looping twice
-
- // Clean out what we dont want and count what we want
- while(li.hasNext()) {
- RtcpPkt aPkt = li.next();
- if(aPkt.received) {
- //This is a packet received, we keep these for
- // 2000ms to avoid redundant feedback
- if(aPkt.time < keepDelay)
- li.remove();
- } else {
- //This is a packet we havent sent yet
- if(aPkt.time < maxDelay) {
- li.remove();
- } else {
- count++;
- }
- }
- }
-
- // Gather what we want to return
- if(count != 0) {
- li = ll.listIterator();
- RtcpPkt[] ret = new RtcpPkt[count];
-
- while(count > 0) {
- RtcpPkt aPkt = li.next();
- if(! aPkt.received) {
- ret[ret.length - count] = aPkt;
- count--;
- }
- }
- return ret;
- }
- }
-
- return null;
- }
-
- /**
- * Cleans the feeback queue of any packets that have expired,
- * ie feedback packet that are no longer relevant.
- *
- * @param ssrc The SSRC of the user who has left, negative value -> general cleanup
- */
- synchronized protected void cleanFbQueue(long ssrc) {
- if(this.fbQueue == null)
- return;
-
- if(ssrc > 0) {
- this.fbQueue.remove(ssrc);
- } else {
- Enumeration<LinkedList<RtcpPkt>> enu = this.fbQueue.elements();
- long curTime = System.currentTimeMillis();
- long maxDelay = curTime - rtpSession.fbMaxDelay;
- long keepDelay = curTime - 2000;
-
- while(enu.hasMoreElements()) {
- ListIterator<RtcpPkt> li = enu.nextElement().listIterator();
- while(li.hasNext()) {
- RtcpPkt aPkt = li.next();
- if(aPkt.received) {
- //This is a packet received, we keep these for
- // 2000ms to avoid redundant feedback
- if(aPkt.time < keepDelay)
- li.remove();
- } else {
- //This is a packet we havent sent yet
- if(aPkt.time < maxDelay)
- li.remove();
- }
- }
- }
- }
- }
-
- /**
- * Check whether the conditions are satisfied to send a feedbkac packet immediately.
- *
- * @return true if they are, false otherwise
- */
- protected boolean fbSendImmediately() {
- if(rtpSession.partDb.ssrcTable.size() > this.rtpSession.fbEarlyThreshold
- && rtpSession.partDb.receivers.size() > this.rtpSession.fbEarlyThreshold)
- return false;
-
- return true;
- }
-
-
- /**
- * Check whether the conditions are satisfied to send a feedbkac packet immediately.
- *
- * @return true if they are, false otherwise
- */
- protected boolean fbSendEarly() {
- if(rtpSession.partDb.ssrcTable.size() > this.rtpSession.fbRegularThreshold
- && rtpSession.partDb.receivers.size() > this.rtpSession.fbRegularThreshold)
- return false;
-
- return true;
- }
-
- /**
- * Wake the sender thread because of this ssrc
- *
- * @param ssrc that has feedback waiting.
- */
- protected void wakeSenderThread(long ssrc) {
- this.fbWaiting = ssrc;
- this.senderThrd.interrupt();
-
- // Give it a chance to catch up
- try { Thread.sleep(0,1); } catch (Exception e){ };
- }
-
- /**
- * Compares two packets to check whether they are equivalent feedback messages,
- * to avoid sending the same feedback to a host twice.
- *
- * Expect false negatives, but not false positives.
- *
- * @param one packet
- * @param two packet
- * @return true if they are equivalent, false otherwise
- */
- private boolean equivalent(RtcpPkt one, RtcpPkt two) {
- // Cheap checks
- if(one.packetType != two.packetType)
- return false;
-
- if(one.itemCount != two.itemCount)
- return false;
-
- if(one.packetType == 205) {
- // RTP Feedback, i.e. a NACK
- RtcpPktRTPFB pktone = (RtcpPktRTPFB) one;
- RtcpPktRTPFB pkttwo = (RtcpPktRTPFB) two;
-
- if(pktone.ssrcMediaSource != pkttwo.ssrcMediaSource)
- return false;
-
- if(Arrays.equals(pktone.BLP,pkttwo.BLP)
- && Arrays.equals(pktone.BLP,pkttwo.BLP))
- return true;
-
- return true;
- } else if(one.packetType == 206) {
- RtcpPktPSFB pktone = (RtcpPktPSFB) one;
- RtcpPktPSFB pkttwo = (RtcpPktPSFB) two;
-
- if(pktone.ssrcMediaSource != pkttwo.ssrcMediaSource)
- return false;
-
- switch(one.itemCount) {
- case 1: // Picture Loss Indication
- return true;
-
- case 2: // Slice Loss Indication
- // This will not work if the slice loss indicators are in different order
- if(pktone.sliFirst.length == pkttwo.sliFirst.length
- && Arrays.equals(pktone.sliFirst, pkttwo.sliFirst)
- && Arrays.equals(pktone.sliNumber, pkttwo.sliNumber)
- && Arrays.equals(pktone.sliPictureId, pkttwo.sliPictureId))
- return true;
- break;
- case 3: // Reference Picture Selection Indication
- if(Arrays.equals(pktone.rpsiBitString, pkttwo.rpsiBitString))
- return true;
- break;
- case 15: // Application Layer Feedback Messages
- // This will not work if the padding scheme is different
- if(pktone.sliFirst.length == pkttwo.sliFirst.length
- && Arrays.equals(pktone.alfBitString, pkttwo.alfBitString))
- return true;
- break;
- default:
-
- }
- return true;
- } else {
- System.out.println("!!!! RTCPSession.equivalentPackets() encountered unexpected packet type!");
- }
- return false;
- }
-}
-