OpalJitterBuffer Class Reference

#include <jitter.h>

Inheritance diagram for OpalJitterBuffer:

Data Structures
struct	Init
	Initialisation information. More...

Public Member Functions
Construction
	OpalJitterBuffer (const Init &init)
virtual	~OpalJitterBuffer ()
Overrides from PObject
void	PrintOn (ostream &strm) const
Operations
virtual void	Start ()
	Start jitter buffer. More...
void	SetDelay (const Init &init)
void	Reset ()
virtual PBoolean	WriteData (const RTP_DataFrame &frame, PTimeInterval tick=PTimer::Tick())
virtual PBoolean	ReadData (RTP_DataFrame &frame, PTimeInterval tick=PTimer::Tick())
DWORD	GetCurrentJitterDelay () const
DWORD	GetMinJitterDelay () const
DWORD	GetMaxJitterDelay () const
unsigned	GetTimeUnits () const
DWORD	GetPacketsTooLate () const
DWORD	GetBufferOverruns () const
DWORD	GetMaxConsecutiveMarkerBits () const
void	SetMaxConsecutiveMarkerBits (DWORD max)

Protected Types
enum	{ e_SynchronisationStart, e_SynchronisationFill, e_SynchronisationShrink, e_SynchronisationDone }
typedef std::map< DWORD, RTP_DataFrame >	FrameMap

Protected Member Functions
DWORD	CalculateRequiredTimestamp (DWORD playOutTimestamp) const
bool	AdjustCurrentJitterDelay (int delta)

Protected Attributes
unsigned	m_timeUnits
PINDEX	m_packetSize
DWORD	m_minJitterDelay
	Minimum jitter delay in timestamp units. More...
DWORD	m_maxJitterDelay
	Maximum jitter delay in timestamp units. More...
int	m_jitterGrowTime
	Amount to increase jitter delay by when get "late" packet. More...
DWORD	m_jitterShrinkPeriod
int	m_jitterShrinkTime
	Amount to shrink jitter delay by if consistently filled. More...
DWORD	m_silenceShrinkPeriod
	Reduce jitter delay is silent for this long. More...
int	m_silenceShrinkTime
	Amount to shrink jitter delay by if consistently silent. More...
DWORD	m_jitterDriftPeriod
int	m_currentJitterDelay
DWORD	m_packetsTooLate
DWORD	m_bufferOverruns
DWORD	m_consecutiveMarkerBits
DWORD	m_maxConsecutiveMarkerBits
DWORD	m_consecutiveLatePackets
DWORD	m_consecutiveOverflows
DWORD	m_consecutiveEmpty
unsigned	m_frameTimeCount
uint64_t	m_frameTimeSum
DWORD	m_incomingFrameTime
DWORD	m_lastSequenceNum
DWORD	m_lastTimestamp
DWORD	m_lastSyncSource
DWORD	m_bufferFilledTime
DWORD	m_bufferLowTime
DWORD	m_bufferEmptiedTime
int	m_timestampDelta
enum OpalJitterBuffer:: { ... }	m_synchronisationState
FrameMap	m_frames
PMutex	m_bufferMutex
RTP_JitterBufferAnalyser *	m_analyser

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

Member Typedef Documentation

typedef std::map<DWORD, RTP_DataFrame> OpalJitterBuffer::FrameMap

protected

Member Enumeration Documentation

anonymous enum

protected

Enumerator
e_SynchronisationStart
e_SynchronisationFill
e_SynchronisationShrink
e_SynchronisationDone

Constructor & Destructor Documentation

OpalJitterBuffer::OpalJitterBuffer

(

const Init &

init

)

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

Parameters

init	Initialisation information

virtual OpalJitterBuffer::~OpalJitterBuffer ( )

virtual

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

Member Function Documentation

bool OpalJitterBuffer::AdjustCurrentJitterDelay ( int  delta )

protected

DWORD OpalJitterBuffer::CalculateRequiredTimestamp ( DWORD  playOutTimestamp ) const

protected

DWORD OpalJitterBuffer::GetBufferOverruns ( ) const

inline

Get total number received packets that overran the jitter buffer.

References m_bufferOverruns.

DWORD OpalJitterBuffer::GetCurrentJitterDelay ( ) const

inline

Get current delay for jitter buffer.

References m_currentJitterDelay.

DWORD OpalJitterBuffer::GetMaxConsecutiveMarkerBits ( ) const

inline

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

References m_maxConsecutiveMarkerBits.

DWORD OpalJitterBuffer::GetMaxJitterDelay ( ) const

inline

Get maximum delay for jitter buffer.

References m_maxJitterDelay.

DWORD OpalJitterBuffer::GetMinJitterDelay ( ) const

inline

Get minimum delay for jitter buffer.

References m_minJitterDelay.

DWORD OpalJitterBuffer::GetPacketsTooLate ( ) const

inline

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

References m_packetsTooLate.

unsigned OpalJitterBuffer::GetTimeUnits ( ) const

inline

Get time units.

References m_timeUnits.

void OpalJitterBuffer::PrintOn

(

ostream &

strm

)

const

Report the statistics for this jitter instance

virtual PBoolean OpalJitterBuffer::ReadData ( RTP_DataFrame &  frame, PTimeInterval  tick = PTimer::Tick()  )

virtual

Read a data frame from the jitter buffer. This function never blocks. If no data is available, an RTP packet with zero payload size is returned.

Parameters

frame	Frame to extract from jitter buffer
tick	Real time tick for packet removal

void OpalJitterBuffer::Reset

(

)

Reset jitter buffer.

void OpalJitterBuffer::SetDelay

(

const Init &

init

)

Set the maximum delay the jitter buffer will operate to.

Parameters

init	Initialisation information

void OpalJitterBuffer::SetMaxConsecutiveMarkerBits ( DWORD  max )

inline

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

References m_maxConsecutiveMarkerBits.

virtual void OpalJitterBuffer::Start ( )

inlinevirtual

Start jitter buffer.

Reimplemented in OpalJitterBufferThread.

virtual PBoolean OpalJitterBuffer::WriteData ( const RTP_DataFrame &  frame, PTimeInterval  tick = PTimer::Tick()  )

virtual

Write data frame from the RTP channel.

Parameters

frame	Frame to feed into jitter buffer
tick	Real time tick for packet arrival

Field Documentation

RTP_JitterBufferAnalyser* OpalJitterBuffer::m_analyser

protected

DWORD OpalJitterBuffer::m_bufferEmptiedTime

protected

DWORD OpalJitterBuffer::m_bufferFilledTime

protected

DWORD OpalJitterBuffer::m_bufferLowTime

protected

PMutex OpalJitterBuffer::m_bufferMutex

protected

DWORD OpalJitterBuffer::m_bufferOverruns

protected

Referenced by GetBufferOverruns().

DWORD OpalJitterBuffer::m_consecutiveEmpty

protected

DWORD OpalJitterBuffer::m_consecutiveLatePackets

protected

DWORD OpalJitterBuffer::m_consecutiveMarkerBits

protected

DWORD OpalJitterBuffer::m_consecutiveOverflows

protected

int OpalJitterBuffer::m_currentJitterDelay

protected

Referenced by GetCurrentJitterDelay().

FrameMap OpalJitterBuffer::m_frames

protected

unsigned OpalJitterBuffer::m_frameTimeCount

protected

uint64_t OpalJitterBuffer::m_frameTimeSum

protected

DWORD OpalJitterBuffer::m_incomingFrameTime

protected

DWORD OpalJitterBuffer::m_jitterDriftPeriod

protected

int OpalJitterBuffer::m_jitterGrowTime

protected

Amount to increase jitter delay by when get "late" packet.

DWORD OpalJitterBuffer::m_jitterShrinkPeriod

protected

  Period (in timestamp units) over which buffer is

consistently filled before shrinking

int OpalJitterBuffer::m_jitterShrinkTime

protected

Amount to shrink jitter delay by if consistently filled.

DWORD OpalJitterBuffer::m_lastSequenceNum

protected

DWORD OpalJitterBuffer::m_lastSyncSource

protected

DWORD OpalJitterBuffer::m_lastTimestamp

protected

DWORD OpalJitterBuffer::m_maxConsecutiveMarkerBits

protected

Referenced by GetMaxConsecutiveMarkerBits(), and SetMaxConsecutiveMarkerBits().

DWORD OpalJitterBuffer::m_maxJitterDelay

protected

Maximum jitter delay in timestamp units.

Referenced by GetMaxJitterDelay().

DWORD OpalJitterBuffer::m_minJitterDelay

protected

Minimum jitter delay in timestamp units.

Referenced by GetMinJitterDelay().

PINDEX OpalJitterBuffer::m_packetSize

protected

DWORD OpalJitterBuffer::m_packetsTooLate

protected

Referenced by GetPacketsTooLate().

DWORD OpalJitterBuffer::m_silenceShrinkPeriod

protected

Reduce jitter delay is silent for this long.

int OpalJitterBuffer::m_silenceShrinkTime

protected

Amount to shrink jitter delay by if consistently silent.

enum { ... } OpalJitterBuffer::m_synchronisationState

int OpalJitterBuffer::m_timestampDelta

protected

unsigned OpalJitterBuffer::m_timeUnits

protected

Referenced by GetTimeUnits().

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

• jitter.h