org.jitsi.impl.neomedia.transform

Class RetransmissionRequesterDelegate

java.lang.Object

org.jitsi.impl.neomedia.transform.RetransmissionRequesterDelegate

All Implemented Interfaces:

Runnable, org.jitsi.utils.concurrent.RecurringRunnable

public class RetransmissionRequesterDelegate
extends Object
implements org.jitsi.utils.concurrent.RecurringRunnable

Detects lost RTP packets for a particular RtpChannel and requests their retransmission by sending RTCP NACK packets.

Author:

Boris Grozev, George Politis, bbaldino

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_MISSING If more than MAX_MISSING consecutive packets are lost, we will not request retransmissions for them, but reset our state instead.
static int	MAX_REQUESTS The maximum number of retransmission requests to be sent for a single RTP packet.
static int	RE_REQUEST_AFTER_MILLIS The interval after which another retransmission request will be sent for a packet, unless it arrives.
protected org.jitsi.utils.TimeProvider	timeProvider
static long	WAKEUP_INTERVAL_MILLIS The interval we'll ask the RecurringRunnableExecutor to check back in if there is no current work TODO(brian): i think we should actually be able to get rid of this and just rely on scheduled work and the 'work ready now' callback
protected Runnable	workReadyCallback A callback which allows this class to signal it has nack work that is ready to be run

Constructor Summary

Constructors

Constructor and Description
RetransmissionRequesterDelegate(MediaStream stream, org.jitsi.utils.TimeProvider timeProvider) Initializes a new RetransmissionRequesterDelegate for the given RtpChannel.

Method Summary

Modifier and Type	Method and Description
protected List<NACKPacket>	createNackPackets(long now, List<org.jitsi.impl.neomedia.transform.RetransmissionRequesterDelegate.Requester> dueRequesters) Gather the packets currently marked as missing and create NACKs for them
long	getTimeUntilNextRun()
void	packetReceived(long ssrc, int seqNum) Notify this requester that a packet has been received
void	run()
void	setSenderSsrc(long ssrc)
void	setWorkReadyCallback(Runnable workReadyCallback)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MAX_MISSING

public static final int MAX_MISSING

If more than MAX_MISSING consecutive packets are lost, we will not request retransmissions for them, but reset our state instead.

See Also:

Constant Field Values

MAX_REQUESTS

public static final int MAX_REQUESTS

The maximum number of retransmission requests to be sent for a single RTP packet.

See Also:

Constant Field Values

RE_REQUEST_AFTER_MILLIS

public static final int RE_REQUEST_AFTER_MILLIS

The interval after which another retransmission request will be sent for a packet, unless it arrives. Ideally this should not be a constant, but should be based on the RTT to the endpoint.

See Also:

Constant Field Values

WAKEUP_INTERVAL_MILLIS

public static final long WAKEUP_INTERVAL_MILLIS

The interval we'll ask the RecurringRunnableExecutor to check back in if there is no current work TODO(brian): i think we should actually be able to get rid of this and just rely on scheduled work and the 'work ready now' callback

See Also:

Constant Field Values

timeProvider

protected final org.jitsi.utils.TimeProvider timeProvider

workReadyCallback

protected Runnable workReadyCallback

A callback which allows this class to signal it has nack work that is ready to be run

Constructor Detail

RetransmissionRequesterDelegate

public RetransmissionRequesterDelegate(MediaStream stream,
                                       org.jitsi.utils.TimeProvider timeProvider)

Initializes a new RetransmissionRequesterDelegate for the given RtpChannel.

Parameters:

stream - the MediaStream that the instance belongs to.

Method Detail

packetReceived

public void packetReceived(long ssrc,
                           int seqNum)

Notify this requester that a packet has been received

getTimeUntilNextRun

public long getTimeUntilNextRun()

Specified by:

getTimeUntilNextRun in interface org.jitsi.utils.concurrent.RecurringRunnable

setWorkReadyCallback

public void setWorkReadyCallback(Runnable workReadyCallback)

run

public void run()

Specified by:

run in interface Runnable

createNackPackets

protected List<NACKPacket> createNackPackets(long now,
                                             List<org.jitsi.impl.neomedia.transform.RetransmissionRequesterDelegate.Requester> dueRequesters)

Gather the packets currently marked as missing and create NACKs for them

Parameters:

dueRequesters - the requesters which are due to have nack packets generated

setSenderSsrc

public void setSenderSsrc(long ssrc)