www.pudn.com > openh323-v1_15_1-src.zip > openh323.dxx

/**@name OpenH323 Libaray 
 
	This is a Open Source class library for the development of applications 
	that wish to use the H.323 protocol for multi-media communications over 
	packet based networks. 
 
@memo	A Class Libarary implementing the H.323 Protocol. 
@version 1.7 
@author	Equivalence Pty. Ltd. 
*/ 
  
//@{ 
 
/**@name Introduction 
\begin{center} 
 	{\Large{\bf OpenH323 Class Library}} 
\end{center} 
 
OpenH323 
 
*/ 
  
/**@name Architecture 
\begin{center} 
 	{\Large{\bf OpenH323 Architecture}} 
\end{center} 
 
The fundamental object of the ownership hierarchy is of the H323Endpoint  
class. An application would typically have one instance of a descendant of  
this class. The application defined descendant would set up defaults for  
various H323 parameters (timeouts etc), the most important of which is the  
capability table which defines the codecs and channel types the application  
is capable of handling. 
 
Also created by the application in the H323Endpoint would be instances of one  
or more descendants of the H323Listener class. There is a descendant of this  
class for each protocol that is supported. For example H323ListenerIP would  
be for Internet use. Each listener spawns a thread that monitors its protocol  
and when a new incoming call is detected, creates an instance of a  
H323Transport class descendent. As for the H323Listener class, there is a  
descendent for each protocol supported, eg H323TransportIP. 
 
When the first PDU arrives on a H323Transport using the Q.931 and H.225  
protocols, there is a call reference that identifies the connection that has  
been made. These connections are embodied by the H323Connection class, which  
contains all of the state information for a connection between H323 endpoints.  
The H323Endpoint instance keeps track of these active connections. If there  
is no connection for the call reference number already, a new one is created  
and H323 signalling negotiations begun. 
 
An application would often have the system create an instance of a descendant  
of the H323Connection class, rather than that class itself. This is so that  
any of a large number of virtual methods may be overridden. These virtual  
methods are "callback" functions by the library to allow the application to  
either obtain information or modify the behaviour at various phases of the  
protocol negotiations. For example, there is a callback for when an incoming  
call is in progress and the application user should be "alerted". This is  
highly application specific being anything from a simple audible beep to  
displaying a pop up window with bells and whistles. 
 
The H323Negotiator classes are used to maintain the state and functionality  
of each command or variable defined by the H.245 protocol. Their main reason  
for existence is actually to reduce the scope of the h225.h and h245.h files,  
which define many hundreds of classes. A user of the H323Connection class  
thus does not have to include all of these classes on every compilation unit. 
 
During some of the H.245 negotiations, logical channels may be created, both  
by the remote endpoint and by the local application. The H323Channel class  
descendants represents this. A typical use of one of these classes is to open  
a stream of encoded audio data. The H323Channel class would create a  
H323Codec using the H323Capability that was passed during the protocol  
negotiations. 
 
*/ 
  
/**@name	Using OpenH323 
Detailed tutorials will be forthcoming. 
 
@memo	Brief examples. 
*/ 
 
/**@name	Class Reference 
 
@memo	Documentation on all classes. 
  */ 
    //@{ 
	//@Include: include/h323.h 
	//@Include: include/h323ep.h 
	//@Include: include/h323con.h 
	//@Include: include/transports.h 
	//@Include: include/gkserver.h 
	//@Include: include/gkclient.h 
	//@Include: include/channels.h 
	//@Include: include/mediafmt.h 
	//@Include: include/h323caps.h 
	//@Include: include/h323t120.h 
	//@Include: include/h323t38.h 
	//@Include: include/codecs.h 
	//@Include: include/h263codec.h 
	//@Include: include/h261codec.h 
	//@Include: include/lid.h 
	//@Include: include/ixjlid.h 
	//@Include: include/vpblid.h 
	//@Include: include/rtp.h 
	//@Include: include/jitter.h 
	//@Include: include/h323rtp.h 
	//@Include: include/h323neg.h 
	//@Include: include/h323pdu.h 
	//@Include: include/h450pdu.h 
	//@Include: include/h225ras.h 
	//@Include: include/h235auth.h 
	//@Include: include/guid.h 
	//@Include: include/t120proto.h 
	//@Include: include/t38proto.h 
	//@Include: include/q931.h 
	//@Include: include/x224.h 
 
        //@Include: plugins/audio/GSM0610/inc/gsm.h 
        //@Include: plugins/audio/LPC_10/lpc10.h 
        //@Include: plugins/audio/Speex/libspeex/lpc.h 
   //@} 
 
//@}