OpalRTPConnection Class Reference

#include <rtpconn.h>

Inheritance diagram for OpalRTPConnection:


Public Member Functions
virtual void	AttachRFC2833HandlerToPatch (PBoolean isSource, OpalMediaPatch &patch)
virtual PBoolean	SendUserInputTone (char tone, unsigned duration=0)
virtual void	SessionFailing (RTP_Session &session)
Construction
	OpalRTPConnection (OpalCall &call, OpalRTPEndPoint &endpoint, const PString &token, unsigned options=0, OpalConnection::StringOptions *stringOptions=NULL)
	~OpalRTPConnection ()
RTP Session Management
virtual unsigned	GetNextSessionID (const OpalMediaType &mediaType, bool isSource)
virtual RTP_Session *	GetSession (unsigned sessionID) const
virtual OpalMediaSession *	GetMediaSession (unsigned sessionID) const
virtual RTP_UDP *	FindSessionByLocalPort (WORD port) const
virtual RTP_Session *	UseSession (const OpalTransport &transport, unsigned sessionID, const OpalMediaType &mediatype, RTP_QOS *rtpqos=NULL)
virtual void	ReleaseSession (unsigned sessionID, PBoolean clearAll=PFalse)
virtual RTP_Session *	CreateSession (const OpalTransport &transport, unsigned sessionID, const OpalMediaType &mediaType, RTP_QOS *rtpqos)
virtual RTP_UDP *	CreateRTPSession (unsigned sessionId, const OpalMediaType &mediaType, bool remoteIsNat)
virtual bool	ChangeSessionID (unsigned fromSessionID, unsigned toSessionID)
NAT Management
virtual PBoolean	RemoteIsNAT () const
virtual PBoolean	IsRTPNATEnabled (const PIPSocket::Address &localAddr, const PIPSocket::Address &peerAddr, const PIPSocket::Address &signalAddr, PBoolean incoming)
Overrides from OpalConnection
virtual PBoolean	GetMediaInformation (unsigned sessionID, MediaInformation &info) const
virtual PBoolean	IsMediaBypassPossible (unsigned sessionID) const
virtual OpalMediaStream *	CreateMediaStream (const OpalMediaFormat &mediaFormat, unsigned sessionID, PBoolean isSource)
virtual void	AdjustMediaFormats (bool local, OpalMediaFormatList &mediaFormats, OpalConnection *otherConnection) const
virtual void	OnPatchMediaStream (PBoolean isSource, OpalMediaPatch &patch)
void	OnMediaCommand (OpalMediaCommand &command, INT extra)
Protected Member Functions
	PDECLARE_NOTIFIER (OpalRFC2833Info, OpalRTPConnection, OnUserInputInlineRFC2833)
	PDECLARE_NOTIFIER (OpalRFC2833Info, OpalRTPConnection, OnUserInputInlineCiscoNSE)
Protected Attributes
list< OpalRTPSessionManager * >	m_allSessions
OpalRTPSessionManager	m_rtpSessions
OpalRFC2833Proto *	rfc2833Handler
PBoolean	remoteIsNAT
PBoolean	useRTPAggregation
Friends
class	OpalRTPSessionManager
Data Structures
struct	MediaInformation

Detailed Description

This is the base class for OpalConnections that use RTP sessions, such as H.323 and SIPconnections to an endpoint.

Constructor & Destructor Documentation

OpalRTPConnection::OpalRTPConnection	(	OpalCall &	call,
		OpalRTPEndPoint &	endpoint,
		const PString &	token,
		unsigned	options = `0`,
		OpalConnection::StringOptions *	stringOptions = `NULL`
	)

Create a new connection.

Parameters:

call	Owner calll for connection
endpoint	Owner endpoint for connection
token	Token to identify the connection
options	Connection options
stringOptions	more complex options

OpalRTPConnection::~OpalRTPConnection ( )

Destroy connection.

Member Function Documentation

virtual void OpalRTPConnection::AdjustMediaFormats	(	bool	local,
		OpalMediaFormatList &	mediaFormats,
		OpalConnection *	otherConnection
	)			const `[virtual]`

Adjust media formats available on a connection. This is called by a connection after it has called OpalCall::GetMediaFormats() to get all media formats that it can use so that an application may remove or reorder the media formats before they are used to open media streams.

This function may also be executed to adjust the media format list for other connections in the call. If this happens then the "otherConnection" parameter will be non-NULL.

The default behaviour calls the OpalEndPoint function of the same name.

Parameters:

local	Media formats a local ones to be presented to remote
mediaFormats	Media formats to use
otherConnection	Other connection we are adjusting media for

Reimplemented from OpalConnection.

virtual void OpalRTPConnection::AttachRFC2833HandlerToPatch	(	PBoolean	isSource,
		OpalMediaPatch &	patch
	)			`[virtual]`

Attaches the RFC 2833 handler to the media patch This method may be called from subclasses, e.g. within OnPatchMediaStream()

Reimplemented from OpalConnection.

virtual bool OpalRTPConnection::ChangeSessionID	(	unsigned	fromSessionID,
		unsigned	toSessionID
	)			`[virtual]`

Change the sessionID for an existing session. This will adjust the RTP session and media streams.

Return false if no such session exists.

Parameters:

fromSessionID	Session ID to search for
toSessionID	Session ID to change to

virtual OpalMediaStream* OpalRTPConnection::CreateMediaStream	(	const OpalMediaFormat &	mediaFormat,
		unsigned	sessionID,
		PBoolean	isSource
	)			`[virtual]`

Create a new media stream. This will create a media stream of an appropriate subclass as required by the underlying connection protocol. For instance H.323 would create an OpalRTPStream.

The sessionID parameter may not be needed by a particular media stream and may be ignored. In the case of an OpalRTPStream it us used.

Note that media streams may be created internally to the underlying protocol. This function is not the only way a stream can come into existance.

Parameters:

mediaFormat	Media format for stream
sessionID	Session number for stream
isSource	Is a source stream

Reimplemented from OpalConnection.

virtual RTP_UDP* OpalRTPConnection::CreateRTPSession	(	unsigned	sessionId,
		const OpalMediaType &	mediaType,
		bool	remoteIsNat
	)			`[virtual]`

Create a new underlying RTP session instance.

virtual RTP_Session* OpalRTPConnection::CreateSession	(	const OpalTransport &	transport,
		unsigned	sessionID,
		const OpalMediaType &	mediaType,
		RTP_QOS *	rtpqos
	)			`[virtual]`

Create and open a new RTP session. The type of RTP session that is created will be compatible with the transport. At this time only IP (RTP over UDP) is supported.

virtual RTP_UDP* OpalRTPConnection::FindSessionByLocalPort ( WORD port ) const [virtual]

Find an RTP session for the specified local port. If there is no session, NULL is returned.

Parameters:

port

Local port number

virtual PBoolean OpalRTPConnection::GetMediaInformation	(	unsigned	sessionID,
		MediaInformation &	info
	)			const `[virtual]`

Get information on the media channel for the connection. The default behaviour checked the mediaTransportAddresses dictionary for the session ID and returns information based on that. It also uses the rfc2833Handler variable for that part of the info.

It is up to the descendant class to assure that the mediaTransportAddresses dictionary is set correctly before OnIncomingCall() is executed.

Parameters:

sessionID	Session ID for media channel
info	Information on media channel

virtual OpalMediaSession* OpalRTPConnection::GetMediaSession ( unsigned sessionID ) const [virtual]

Parameters:

sessionID

RTP session number

virtual unsigned OpalRTPConnection::GetNextSessionID	(	const OpalMediaType &	mediaType,
		bool	isSource
	)			`[virtual]`

Get next available session ID for the media type.

Parameters:

mediaType	Media type of stream being opened
isSource	Stream is a source/sink

Reimplemented from OpalConnection.

Reimplemented in H323Connection.

virtual RTP_Session* OpalRTPConnection::GetSession ( unsigned sessionID ) const [virtual]

Get an RTP session for the specified ID. If there is no session of the specified ID, NULL is returned.

Parameters:

sessionID

RTP session number

virtual PBoolean OpalRTPConnection::IsMediaBypassPossible ( unsigned sessionID ) const [virtual]

See if the media can bypass the local host.

The default behaviour returns PTrue if the session is audio or video.

Parameters:

sessionID

Session ID for media channel

Reimplemented from OpalConnection.

virtual PBoolean OpalRTPConnection::IsRTPNATEnabled	(	const PIPSocket::Address &	localAddr,
		const PIPSocket::Address &	peerAddr,
		const PIPSocket::Address &	signalAddr,
		PBoolean	incoming
	)			`[virtual]`

Determine if the RTP session needs to accommodate a NAT router. For endpoints that do not use STUN or something similar to set up all the correct protocol embeddded addresses correctly when a NAT router is between the endpoints, it is possible to still accommodate the call, with some restrictions. This function determines if the RTP can proceed with special NAT allowances.

The special allowance is that the RTP code will ignore whatever the remote indicates in the protocol for the address to send RTP data and wait for the first packet to arrive from the remote and will then proceed to send all RTP data back to that address AND port.

The default behaviour checks the values of the physical link (localAddr/peerAddr) against the signaling address the remote indicated in the protocol, eg H.323 SETUP sourceCallSignalAddress or SIP "To" or "Contact" fields, and makes a guess that the remote is behind a NAT router.

Parameters:

localAddr	Local physical address of connection
peerAddr	Remote physical address of connection
signalAddr	Remotes signaling address as indicated by protocol of connection
incoming	Incoming/outgoing connection

void OpalRTPConnection::OnMediaCommand	(	OpalMediaCommand &	command,
		INT	extra
	)

Notifier function for OpalVideoUpdatePicture. Calls the SendIntraFrameRequest on the rtp session

Reimplemented in H323Connection, and SIPConnection.

virtual void OpalRTPConnection::OnPatchMediaStream	(	PBoolean	isSource,
		OpalMediaPatch &	patch
	)			`[virtual]`

Call back when patching a media stream. This function is called when a connection has created a new media patch between two streams. This is usually called twice per media patch, once for the source stream and once for the sink stream.

Note this is not called within the context of the patch thread and is called before that thread has started.

Parameters:

isSource	Is source/sink call
patch	New patch

Reimplemented from OpalConnection.

OpalRTPConnection::PDECLARE_NOTIFIER	(	OpalRFC2833Info	,
		OpalRTPConnection	,
		OnUserInputInlineCiscoNSE
	)			`[protected]`

OpalRTPConnection::PDECLARE_NOTIFIER	(	OpalRFC2833Info	,
		OpalRTPConnection	,
		OnUserInputInlineRFC2833
	)			`[protected]`

virtual void OpalRTPConnection::ReleaseSession	(	unsigned	sessionID,
		PBoolean	clearAll = `PFalse`
	)			`[virtual]`

Release the session.

Parameters:

sessionID	RTP session number
clearAll	Clear all sessions

virtual PBoolean OpalRTPConnection::RemoteIsNAT ( ) const [inline, virtual]

Return PTrue if the remote appears to be behind a NAT firewall

virtual PBoolean OpalRTPConnection::SendUserInputTone	(	char	tone,
		unsigned	duration = `0`
	)			`[virtual]`

Send a user input indication to the remote endpoint. This sends DTMF emulation user input. If something more sophisticated than the simple tones that can be sent using the SendUserInput() function.

A duration of zero indicates that no duration is to be indicated. A non-zero logical channel indicates that the tone is to be syncronised with the logical channel at the rtpTimestamp value specified.

The tone parameter must be one of "0123456789#*ABCD!" where '!' indicates a hook flash. If tone is a ' ' character then a signalUpdate PDU is sent that updates the last tone indication sent. See the H.245 specifcation for more details on this.

The default behaviour sends the tone using RFC2833.

Parameters:

tone	DTMF tone code
duration	Duration of tone in milliseconds

Reimplemented from OpalConnection.

Reimplemented in H323Connection, and SIPConnection.

virtual void OpalRTPConnection::SessionFailing ( RTP_Session & session ) [virtual]

virtual RTP_Session* OpalRTPConnection::UseSession	(	const OpalTransport &	transport,
		unsigned	sessionID,
		const OpalMediaType &	mediatype,
		RTP_QOS *	rtpqos = `NULL`
	)			`[virtual]`