OpalSilenceDetector Class Reference

#include <silencedetect.h>

Inheritance diagram for OpalSilenceDetector:

OpalLineSilenceDetector OpalPCM16SilenceDetector

List of all members.

Classes

struct  Params

Public Types

enum  Mode { NoSilenceDetection, FixedSilenceDetection, AdaptiveSilenceDetection, NumModes }

Public Member Functions

Construction
 OpalSilenceDetector (const Params &newParam)

Basic operations

PNotifier receiveHandler
Params param
unsigned lastTimestamp
unsigned receivedTime
unsigned levelThreshold
unsigned signalMinimum
unsigned silenceMaximum
unsigned signalReceivedTime
unsigned silenceReceivedTime
bool inTalkBurst
const PNotifier & GetReceiveHandler () const
void SetParameters (const Params &newParam)
Mode GetStatus (PBoolean *isInTalkBurst, unsigned *currentThreshold) const
virtual unsigned GetAverageSignalLevel (const BYTE *buffer, PINDEX size)=0
 PDECLARE_NOTIFIER (RTP_DataFrame, OpalSilenceDetector, ReceivedPacket)


Member Enumeration Documentation

Enumerator:
NoSilenceDetection 
FixedSilenceDetection 
AdaptiveSilenceDetection 
NumModes 


Constructor & Destructor Documentation

OpalSilenceDetector::OpalSilenceDetector ( const Params newParam  ) 

Create a new connection.

Parameters:
newParam New parameters for silence detector


Member Function Documentation

virtual unsigned OpalSilenceDetector::GetAverageSignalLevel ( const BYTE *  buffer,
PINDEX  size 
) [pure virtual]

Get the average signal level in the stream. This is called from within the silence detection algorithm to calculate the average signal level of the last data frame read from the stream.

The default behaviour returns UINT_MAX which indicates that the average signal has no meaning for the stream.

Parameters:
buffer RTP payload being detected
size Size of payload buffer

Implemented in OpalPCM16SilenceDetector, and OpalLineSilenceDetector.

const PNotifier& OpalSilenceDetector::GetReceiveHandler (  )  const [inline]

References receiveHandler.

Mode OpalSilenceDetector::GetStatus ( PBoolean *  isInTalkBurst,
unsigned *  currentThreshold 
) const

Get silence detection status

The inTalkBurst value is PTrue if packet transmission is enabled and PFalse if it is being suppressed due to silence.

The currentThreshold value is the value from 0 to 32767 which is used as the threshold value for 16 bit PCM data.

OpalSilenceDetector::PDECLARE_NOTIFIER ( RTP_DataFrame  ,
OpalSilenceDetector  ,
ReceivedPacket   
) [protected]

void OpalSilenceDetector::SetParameters ( const Params newParam  ) 

Set the silence detector parameters. This enables, disables the silence detector as well as adjusting its "agression". The deadband periods are in audio samples of 8kHz.

Parameters:
newParam New parameters for silence detector


Member Data Documentation

unsigned OpalSilenceDetector::lastTimestamp [protected]

unsigned OpalSilenceDetector::receivedTime [protected]

PNotifier OpalSilenceDetector::receiveHandler [protected]

Referenced by GetReceiveHandler().

unsigned OpalSilenceDetector::signalMinimum [protected]


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

Generated on Tue Jul 21 02:52:19 2009 for OPAL by  doxygen 1.5.9