OpalJitterBuffer Class Reference

#include <jitter.h>

Inheritance diagram for OpalJitterBuffer:

List of all members.

Public Member Functions
	OpalJitterBuffer (unsigned minJitterDelay, unsigned maxJitterDelay, unsigned timeUnits=8, PINDEX stackSize=30000)
	~OpalJitterBuffer ()
void	PrintOn (ostream &strm) const
virtual BOOL	OnReadPacket (RTP_DataFrame &frame, BOOL loop)=0
void	SetDelay (unsigned minJitterDelay, unsigned maxJitterDelay)
void	UseImmediateReduction (BOOL state)
virtual BOOL	ReadData (DWORD timestamp, RTP_DataFrame &frame)
DWORD	GetJitterTime () const
unsigned	GetTimeUnits () const
DWORD	GetPacketsTooLate () const
DWORD	GetBufferOverruns () const
DWORD	GetMaxConsecutiveMarkerBits () const
void	SetMaxConsecutiveMarkerBits (DWORD max)
void	Resume (PHandleAggregator *aggregator=NULL)
	PDECLARE_NOTIFIER (PThread, OpalJitterBuffer, JitterThreadMain)
BOOL	WaitForTermination (const PTimeInterval &t)
Protected Member Functions
BOOL	Init (Entry *&currentReadFrame, BOOL &markerWarning)
BOOL	PreRead (Entry *&currentReadFrame, BOOL &markerWarning)
BOOL	OnRead (Entry *&currentReadFrame, BOOL &markerWarning, BOOL loop)
void	DeInit (Entry *&currentReadFrame, BOOL &markerWarning)
Protected Attributes
PINDEX	bufferSize
DWORD	minJitterTime
DWORD	maxJitterTime
DWORD	maxConsecutiveMarkerBits
unsigned	timeUnits
unsigned	currentDepth
DWORD	currentJitterTime
DWORD	packetsTooLate
unsigned	bufferOverruns
unsigned	consecutiveBufferOverruns
DWORD	consecutiveMarkerBits
PTimeInterval	consecutiveEarlyPacketStartTime
DWORD	lastWriteTimestamp
PTimeInterval	lastWriteTick
DWORD	jitterCalc
DWORD	targetJitterTime
unsigned	jitterCalcPacketCount
BOOL	doJitterReductionImmediately
BOOL	doneFreeTrash
Entry *	oldestFrame
Entry *	newestFrame
Entry *	freeFrames
Entry *	currentWriteFrame
PMutex	bufferMutex
BOOL	shuttingDown
BOOL	preBuffering
BOOL	doneFirstWrite
RTP_JitterBufferAnalyser *	analyser
PThread *	jitterThread
PINDEX	jitterStackSize
RTP_AggregatedHandle *	aggregratedHandle
Classes
class	Entry

---

Detailed Description

This is an Abstract jitter buffer, which can be used simply in any application. The user is required to use a descendant of this class, and provide a "OnReadPacket" method, so that network packets can be placed in this class instance

---

Constructor & Destructor Documentation

OpalJitterBuffer::OpalJitterBuffer	(	unsigned	minJitterDelay,
		unsigned	maxJitterDelay,
		unsigned	timeUnits = 8,
		PINDEX	stackSize = 30000
	)

Constructor for this jitter buffer. The size of this buffer can be altered later with the SetDelay method

Parameters:

minJitterDelay	Minimum delay in RTP timestamp units
maxJitterDelay	Maximum delay in RTP timestamp units
timeUnits	Time units, usually 8 or 16
stackSize	Stack size for jitter thread

OpalJitterBuffer::~OpalJitterBuffer

(

)

Destructor, which closes this down and deletes the internal list of frames

---

Member Function Documentation

void OpalJitterBuffer::PrintOn

(

ostream &

strm

)

const

Report the statistics for this jitter instance

virtual BOOL OpalJitterBuffer::OnReadPacket	(	RTP_DataFrame &	frame,
		BOOL	loop
	)			[pure virtual]

This method is where this OpalJitterBuffer collects data from the outside world. A descendant class of OpalJitterBuffer will override this method

Returns:

TRUE on successful read, FALSE on faulty read.

Parameters:

frame	Frame read from the RTP session
loop	If TRUE, loop as long as data is available, if FALSE, only process once

Implemented in IAX2JitterBuffer, and RTP_JitterBuffer.

void OpalJitterBuffer::SetDelay	(	unsigned	minJitterDelay,
		unsigned	maxJitterDelay
	)

Set the maximum delay the jitter buffer will operate to.

Parameters:

minJitterDelay	Minimum delay in RTP timestamp units
maxJitterDelay	Maximum delay in RTP timestamp units

void OpalJitterBuffer::UseImmediateReduction

(

BOOL

state

)

[inline]

virtual BOOL OpalJitterBuffer::ReadData	(	DWORD	timestamp,
		RTP_DataFrame &	frame
	)			[virtual]

Read a data frame from the RTP channel. Any control frames received are dispatched to callbacks and are not returned by this function. It will block until a data frame is available or an error occurs.

Parameters:

timestamp	Timestamp to read from buffer.
frame	Frame read from the RTP session

DWORD OpalJitterBuffer::GetJitterTime

(

)

const [inline]

Get current delay for jitter buffer.

unsigned OpalJitterBuffer::GetTimeUnits

(

)

const [inline]

Get time units.

DWORD OpalJitterBuffer::GetPacketsTooLate

(

)

const [inline]

Get total number received packets too late to go into jitter buffer.

DWORD OpalJitterBuffer::GetBufferOverruns

(

)

const [inline]

Get total number received packets that overran the jitter buffer.

DWORD OpalJitterBuffer::GetMaxConsecutiveMarkerBits

(

)

const [inline]

Get maximum consecutive marker bits before buffer starts to ignore them.

void OpalJitterBuffer::SetMaxConsecutiveMarkerBits

(

DWORD

max

)

[inline]

Set maximum consecutive marker bits before buffer starts to ignore them.

void OpalJitterBuffer::Resume

(

PHandleAggregator *

aggregator = NULL

)

Start jitter thread

OpalJitterBuffer::PDECLARE_NOTIFIER	(	PThread	,
		OpalJitterBuffer	,
		JitterThreadMain
	)

BOOL OpalJitterBuffer::WaitForTermination

(

const PTimeInterval &

t

)

[inline]

BOOL OpalJitterBuffer::Init	(	Entry *&	currentReadFrame,
		BOOL &	markerWarning
	)			[protected]

BOOL OpalJitterBuffer::PreRead	(	Entry *&	currentReadFrame,
		BOOL &	markerWarning
	)			[protected]

BOOL OpalJitterBuffer::OnRead	(	Entry *&	currentReadFrame,
		BOOL &	markerWarning,
		BOOL	loop
	)			[protected]

void OpalJitterBuffer::DeInit	(	Entry *&	currentReadFrame,
		BOOL &	markerWarning
	)			[protected]

---

Member Data Documentation

PINDEX OpalJitterBuffer::bufferSize [protected]

DWORD OpalJitterBuffer::minJitterTime [protected]

DWORD OpalJitterBuffer::maxJitterTime [protected]

DWORD OpalJitterBuffer::maxConsecutiveMarkerBits [protected]

unsigned OpalJitterBuffer::timeUnits [protected]

unsigned OpalJitterBuffer::currentDepth [protected]

DWORD OpalJitterBuffer::currentJitterTime [protected]

DWORD OpalJitterBuffer::packetsTooLate [protected]

unsigned OpalJitterBuffer::bufferOverruns [protected]

unsigned OpalJitterBuffer::consecutiveBufferOverruns [protected]

DWORD OpalJitterBuffer::consecutiveMarkerBits [protected]

PTimeInterval OpalJitterBuffer::consecutiveEarlyPacketStartTime [protected]

DWORD OpalJitterBuffer::lastWriteTimestamp [protected]

PTimeInterval OpalJitterBuffer::lastWriteTick [protected]

DWORD OpalJitterBuffer::jitterCalc [protected]

DWORD OpalJitterBuffer::targetJitterTime [protected]

unsigned OpalJitterBuffer::jitterCalcPacketCount [protected]

BOOL OpalJitterBuffer::doJitterReductionImmediately [protected]

BOOL OpalJitterBuffer::doneFreeTrash [protected]

Entry* OpalJitterBuffer::oldestFrame [protected]

Entry* OpalJitterBuffer::newestFrame [protected]

Entry* OpalJitterBuffer::freeFrames [protected]

Entry* OpalJitterBuffer::currentWriteFrame [protected]

PMutex OpalJitterBuffer::bufferMutex [protected]

BOOL OpalJitterBuffer::shuttingDown [protected]

BOOL OpalJitterBuffer::preBuffering [protected]

BOOL OpalJitterBuffer::doneFirstWrite [protected]

RTP_JitterBufferAnalyser* OpalJitterBuffer::analyser [protected]

PThread* OpalJitterBuffer::jitterThread [protected]

PINDEX OpalJitterBuffer::jitterStackSize [protected]

RTP_AggregatedHandle* OpalJitterBuffer::aggregratedHandle [protected]

---

The documentation for this class was generated from the following file:

• jitter.h

---