#include <transcoders.h>

Inheritance diagram for OpalFramedTranscoder:

Collaboration diagram for OpalFramedTranscoder:

Public Member Functions
Construction
	OpalFramedTranscoder (const OpalMediaFormat &inputMediaFormat, const OpalMediaFormat &outputMediaFormat)

Operations
virtual bool	UpdateMediaFormats (const OpalMediaFormat &inputMediaFormat, const OpalMediaFormat &outputMediaFormat)

virtual PINDEX	GetOptimalDataFrameSize (PBoolean input) const

virtual PBoolean	Convert (const RTP_DataFrame &input, RTP_DataFrame &output)

virtual PBoolean	ConvertFrame (const BYTE input, BYTE output)

virtual PBoolean	ConvertFrame (const BYTE input, PINDEX &consumed, BYTE output, PINDEX &created)

virtual PBoolean	ConvertSilentFrame (BYTE *output)

Public Member Functions inherited from OpalTranscoder
	OpalTranscoder (const OpalMediaFormat &inputMediaFormat, const OpalMediaFormat &outputMediaFormat)

virtual PBoolean	ExecuteCommand (const OpalMediaCommand &command)

virtual PBoolean	ConvertFrames (const RTP_DataFrame &input, RTP_DataFrameList &output)

PINDEX	GetMaxOutputSize () const

void	SetMaxOutputSize (PINDEX size)

void	SetCommandNotifier (const PNotifier &notifier)

const PNotifier &	GetCommandNotifier () const

void	NotifyCommand (const OpalMediaCommand &command) const
	Notify command notifier of command. More...

unsigned	GetSessionID () const
	Get session ID for the transcoder (from OpalMediaStream) More...

void	SetSessionID (unsigned id)
	Set session ID for the transcoder (from OpalMediaStream) More...

virtual void	SetInstanceID (const BYTE *instance, unsigned instanceLen)

RTP_DataFrame::PayloadTypes	GetPayloadType (PBoolean input) const

virtual bool	AcceptComfortNoise () const

virtual bool	AcceptEmptyPayload () const

virtual bool	AcceptOtherPayloads () const

virtual void	GetStatistics (OpalMediaStatistics &statistics) const

void	CopyTimestamp (RTP_DataFrame &dst, const RTP_DataFrame &src, bool inToOut) const

Public Member Functions inherited from OpalMediaFormatPair
	OpalMediaFormatPair (const OpalMediaFormat &inputMediaFormat, const OpalMediaFormat &outputMediaFormat)

void	PrintOn (ostream &strm) const

virtual Comparison	Compare (const PObject &obj) const

const OpalMediaFormat &	GetInputFormat () const

const OpalMediaFormat &	GetOutputFormat () const

Protected Member Functions
void	CalculateSizes ()

Protected Attributes
PINDEX	inputBytesPerFrame

PINDEX	outputBytesPerFrame

PINDEX	maxOutputDataSize

Protected Attributes inherited from OpalTranscoder
PINDEX	maxOutputSize

PNotifier	commandNotifier

PMutex	updateMutex

unsigned	m_sessionID

bool	outputIsRTP

bool	inputIsRTP

bool	acceptEmptyPayload

bool	acceptOtherPayloads

unsigned	m_inClockRate

unsigned	m_outClockRate

RTP_DataFrame::PayloadTypes	m_lastPayloadType

unsigned	m_consecutivePayloadTypeMismatches

Protected Attributes inherited from OpalMediaFormatPair
OpalMediaFormat	inputMediaFormat

OpalMediaFormat	outputMediaFormat

Additional Inherited Members
Static Public Member Functions inherited from OpalTranscoder
static OpalTranscoder *	Create (const OpalMediaFormat &srcFormat, const OpalMediaFormat &dstFormat, const BYTE *instance=NULL, unsigned instanceLen=0)

static bool	SelectFormats (const OpalMediaType &mediaType, const OpalMediaFormatList &srcFormats, const OpalMediaFormatList &dstFormats, const OpalMediaFormatList &allFormats, OpalMediaFormat &srcFormat, OpalMediaFormat &dstFormat)

static bool	FindIntermediateFormat (const OpalMediaFormat &srcFormat, const OpalMediaFormat &dstFormat, OpalMediaFormat &intermediateFormat)

static OpalMediaFormatList	GetDestinationFormats (const OpalMediaFormat &srcFormat)

static OpalMediaFormatList	GetSourceFormats (const OpalMediaFormat &dstFormat)

static OpalMediaFormatList	GetPossibleFormats (const OpalMediaFormatList &formats)

Detailed Description

This class defines a transcoder implementation class that will encode/decode fixed sized blocks. That is each input block of n bytes is encoded to exactly m bytes of data, eg GSM etc.

An application may create a descendent off this class and override functions as required for descibing a specific transcoder.

Constructor & Destructor Documentation

OpalFramedTranscoder::OpalFramedTranscoder	(	const OpalMediaFormat &	inputMediaFormat,
		const OpalMediaFormat &	outputMediaFormat
	)

Create a new framed transcoder implementation.

Parameters

inputMediaFormat	Input media format
outputMediaFormat	Output media format

Member Function Documentation

void OpalFramedTranscoder::CalculateSizes ( )

protected

virtual PBoolean OpalFramedTranscoder::Convert	(	const RTP_DataFrame &	input,
		RTP_DataFrame &	output
	)

virtual

Convert the data from one format to another. This function takes the input data as a RTP_DataFrame and converts it to its output format, placing it into the RTP_DataFrame provided.

Returns FALSE if the conversion fails.

Parameters

input	Input data
output	Output data

Implements OpalTranscoder.

virtual PBoolean OpalFramedTranscoder::ConvertFrame	(	const BYTE *	input,
		BYTE *	output
	)

virtual

Convert a frame of data from one format to another. This function implicitly knows the input and output frame sizes.

Parameters

input	Input data
output	Output data

virtual PBoolean OpalFramedTranscoder::ConvertFrame	(	const BYTE *	input,
		PINDEX &	consumed,
		BYTE *	output,
		PINDEX &	created
	)

virtual

Parameters

input	Input data
consumed	number of input bytes consumed
output	Output data
created	number of output bytes created

Reimplemented in OpalEmptyFramedAudioTranscoder, and OpalPluginFramedAudioTranscoder.

virtual PBoolean OpalFramedTranscoder::ConvertSilentFrame ( BYTE * output )

virtual

Parameters

output Output data

Reimplemented in OpalPluginFramedAudioTranscoder.

virtual PINDEX OpalFramedTranscoder::GetOptimalDataFrameSize ( PBoolean input ) const

virtual

Get the optimal size for data frames to be converted. This function returns the size of frames that will be most efficient in conversion. A RTP_DataFrame will attempt to provide or use data in multiples of this size. Note that it may not do so, so the transcoder must be able to handle any sized packets.

Parameters

input Flag for input or output data size

Implements OpalTranscoder.

virtual bool OpalFramedTranscoder::UpdateMediaFormats	(	const OpalMediaFormat &	inputMediaFormat,
		const OpalMediaFormat &	outputMediaFormat
	)

virtual

Update the input and output media formats. This can be used to adjust the parameters of a codec at run time. Note you cannot change the basic media format, eg change GSM0610 to G.711, only options for that format, eg 6k3 mode to 5k3 mode in G.723.1. If the formats are different then a OpalMediaFormat::Merge() is performed.

If a format is empty (invalid) it is ignored and does not update the internal variable. In this way only the input or output side can be updated.

The default behaviour updates the inputMediaFormat and outputMediaFormat member variables.

Parameters

inputMediaFormat	Input media format
outputMediaFormat	Output media format

Reimplemented from OpalTranscoder.

Reimplemented in OpalPluginFramedAudioTranscoder.

Field Documentation

PINDEX OpalFramedTranscoder::inputBytesPerFrame

protected

PINDEX OpalFramedTranscoder::maxOutputDataSize

protected

PINDEX OpalFramedTranscoder::outputBytesPerFrame

protected

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

transcoders.h

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation