Package org.jitsi.impl.neomedia.transform.fec

Class FECTransformEngine

java.lang.Object

org.jitsi.impl.neomedia.transform.fec.FECTransformEngine

All Implemented Interfaces:

PacketTransformer, TransformEngine

public class FECTransformEngine
extends Object
implements TransformEngine, PacketTransformer

Implements a PacketTransformer and TransformEngine for RFC5109.

Author:

Boris Grozev, bbaldino

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FECTransformEngine.FecType

Field Summary

Fields

Modifier and Type	Field	Description
protected FECTransformEngine.FecType	fecType	The fec type this transform engine will instantiate
static int	INITIAL_BUFFER_SIZE	Initial size for newly allocated byte arrays.

Constructor Summary

Constructors

Constructor	Description
FECTransformEngine(FECTransformEngine.FecType fecType, byte incomingPT, byte outgoingPT, MediaStream mediaStream)	Initializes a new FECTransformEngine instance.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes this PacketTransformer i.e.
int	getFecRate()	Get the rate at which ulpfec packets will be generated and added to the stream by this PacketTransformer.
PacketTransformer	getRTCPTransformer()	Gets the PacketTransformer for RTCP packets.
PacketTransformer	getRTPTransformer()	Gets the PacketTransformer for RTP packets.
RawPacket[]	reverseTransform(RawPacket[] pkts)	Reverse-transforms each packet in an array of packets.
void	setFecRate(int fecRate)	Sets the rate at which ulpfec packets will be generated and added to the stream by this PacketTransformer.
void	setIncomingPT(byte incomingPT)	Sets the payload type for incoming ulpfec packets.
void	setOutgoingPT(byte outgoingPT)	Sets the payload type for outgoing ulpfec packets.
RawPacket[]	transform(RawPacket[] pkts)	Transforms each packet in an array of packets.

Methods inherited from class java.lang.Object

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

Field Detail

INITIAL_BUFFER_SIZE

public static final int INITIAL_BUFFER_SIZE

Initial size for newly allocated byte arrays.

See Also:

Constant Field Values

fecType

protected FECTransformEngine.FecType fecType

The fec type this transform engine will instantiate

Constructor Detail

FECTransformEngine

public FECTransformEngine(FECTransformEngine.FecType fecType,
                          byte incomingPT,
                          byte outgoingPT,
                          MediaStream mediaStream)

Initializes a new FECTransformEngine instance.

Parameters:

incomingPT - the RTP payload type number for incoming ulpfec packet.

outgoingPT - the RTP payload type number for outgoing ulpfec packet.

Method Detail

reverseTransform

public RawPacket[] reverseTransform(RawPacket[] pkts)

Reverse-transforms each packet in an array of packets. Null values must be ignored. Assumes that all packets in pkts have the same SSRC. Reverse- transforms using the AbstractFECReceiver for the SSRC found in pkts.

Specified by:

reverseTransform in interface PacketTransformer

Parameters:

pkts - the transformed packets to be restored.

Returns:

the restored packets.

transform

public RawPacket[] transform(RawPacket[] pkts)

Transforms each packet in an array of packets. Null values must be ignored. Adds ulpfec packets to the stream (one ulpfec packet after every fecRate media packets.

Specified by:

transform in interface PacketTransformer

Parameters:

pkts - the packets to be transformed

Returns:

the transformed packets

close

public void close()

Closes this PacketTransformer i.e. releases the resources allocated by it and prepares it for garbage collection.

Specified by:

close in interface PacketTransformer

getRTPTransformer

public PacketTransformer getRTPTransformer()

Gets the PacketTransformer for RTP packets.

Specified by:

getRTPTransformer in interface TransformEngine

Returns:

the PacketTransformer for RTP packets

getRTCPTransformer

public PacketTransformer getRTCPTransformer()

Gets the PacketTransformer for RTCP packets. We don't touch RTCP.

Specified by:

getRTCPTransformer in interface TransformEngine

Returns:

the PacketTransformer for RTCP packets

setIncomingPT

public void setIncomingPT(byte incomingPT)

Sets the payload type for incoming ulpfec packets.

Parameters:

incomingPT - the payload type to set

setOutgoingPT

public void setOutgoingPT(byte outgoingPT)

Sets the payload type for outgoing ulpfec packets.

Parameters:

outgoingPT - the payload type to set

setFecRate

public void setFecRate(int fecRate)

Sets the rate at which ulpfec packets will be generated and added to the stream by this PacketTransformer.

Parameters:

fecRate - the rate to set, should be in [0, 16]

getFecRate

public int getFecRate()

Get the rate at which ulpfec packets will be generated and added to the stream by this PacketTransformer.

Returns:

the rate at which ulpfec packets will be generated and added to the stream by this PacketTransformer.