OpalVideoMediaStream Class Reference

#include <mediastrm.h>

Inheritance diagram for OpalVideoMediaStream:

Public Member Functions
Construction

	OpalVideoMediaStream (OpalConnection &conn, const OpalMediaFormat &mediaFormat, unsigned sessionID, PVideoInputDevice inputDevice, PVideoOutputDevice outputDevice, bool autoDeleteInput=true, bool autoDeleteOutput=true)
	~OpalVideoMediaStream ()
Overrides of PChannel class

virtual bool	InternalUpdateMediaFormat (const OpalMediaFormat &mediaFormat)
virtual PBoolean	Open ()
virtual PBoolean	ReadData (BYTE *data, PINDEX size, PINDEX &length)
virtual PBoolean	WriteData (const BYTE *data, PINDEX length, PINDEX &written)
virtual PBoolean	IsSynchronous () const
virtual PBoolean	SetDataSize (PINDEX dataSize, PINDEX frameTime)
virtual PVideoInputDevice *	GetVideoInputDevice () const
virtual PVideoOutputDevice *	GetVideoOutputDevice () const
Protected Member Functions
virtual void	InternalClose ()
Protected Attributes
PVideoInputDevice *	m_inputDevice
PVideoOutputDevice *	m_outputDevice
bool	m_autoDeleteInput
bool	m_autoDeleteOutput
PTimeInterval	m_lastGrabTime

Constructor & Destructor Documentation

OpalVideoMediaStream::OpalVideoMediaStream	(	OpalConnection &	conn,
		const OpalMediaFormat &	mediaFormat,
		unsigned	sessionID,
		PVideoInputDevice *	inputDevice,
		PVideoOutputDevice *	outputDevice,
		bool	autoDeleteInput = `true`,
		bool	autoDeleteOutput = `true`
	)

Construct a new media stream for channel.

Parameters:

	conn	Connection that owns the stream
	mediaFormat	Media format for stream
	sessionID	Session number for stream
	inputDevice	Device to use for video grabbing
	outputDevice	Device to use for video display
	autoDeleteInput	Automatically delete PVideoInputDevice
	autoDeleteOutput	Automatically delete PVideoOutputDevice

OpalVideoMediaStream::~OpalVideoMediaStream ( )

Delete attached channel if autoDelete enabled.

Member Function Documentation

virtual PVideoInputDevice* OpalVideoMediaStream::GetVideoInputDevice ( ) const [inline, virtual]

Get the input device (e.g. for statistics)

References m_inputDevice.

virtual PVideoOutputDevice* OpalVideoMediaStream::GetVideoOutputDevice ( ) const [inline, virtual]

Get the output device (e.g. for statistics)

References m_outputDevice.

virtual void OpalVideoMediaStream::InternalClose ( ) [protected, virtual]

Close any internal components of the stream. This should be used in preference to overriding the Close() function as it is guaranteed to be called exactly once and avoids race conditions in the shut down sequence of a media stream.

Implements OpalMediaStream.

virtual bool OpalVideoMediaStream::InternalUpdateMediaFormat ( const OpalMediaFormat & mediaFormat ) [virtual]

Update the media format. 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.

Parameters:

mediaFormat

New media format

Reimplemented from OpalMediaStream.

virtual PBoolean OpalVideoMediaStream::IsSynchronous ( ) const [virtual]

Indicate if the media stream is synchronous. Returns true for LID streams.

Implements OpalMediaStream.

virtual PBoolean OpalVideoMediaStream::Open ( ) [virtual]

Open the media stream.

The default behaviour sets the OpalLineInterfaceDevice format and calls Resume() on the associated OpalMediaPatch thread.

Reimplemented from OpalMediaStream.

virtual PBoolean OpalVideoMediaStream::ReadData	(	BYTE *	data,
		PINDEX	size,
		PINDEX &	length
	)			`[virtual]`

Read raw media data from the source media stream. The default behaviour simply calls ReadPacket() on the data portion of the RTP_DataFrame and sets the frames timestamp and marker from the internal member variables of the media stream class.

Parameters:

	data	Data buffer to read to
	size	Size of buffer
	length	Length of data actually read

Reimplemented from OpalMediaStream.

virtual PBoolean OpalVideoMediaStream::SetDataSize	(	PINDEX	dataSize,
		PINDEX	frameTime
	)			`[virtual]`

Override size of frame header is included

Parameters:

	dataSize	New data size (in total)
	frameTime	Individual frame time (if applicable)

Reimplemented from OpalMediaStream.

virtual PBoolean OpalVideoMediaStream::WriteData	(	const BYTE *	data,
		PINDEX	length,
		PINDEX &	written
	)			`[virtual]`

Write raw media data to the sink media stream. The default behaviour calls WritePacket() on the data portion of the RTP_DataFrame and and sets the internal timestamp and marker from the member variables of the media stream class.

Parameters: