h323caps.h

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/*
 * h323caps.h
 *
 * H.323 protocol handler
 *
 * Open H323 Library
 *
 * Copyright (c) 1998-2000 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Open H323 Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions of this code were written with the assisance of funding from
 * Vovida Networks, Inc. http://www.vovida.com.
 *
 * Contributor(s): ______________________________________.
 *
 * $Log: h323caps.h,v $
 * Revision 1.47  2004/08/24 14:23:09  csoutheren
 * Fixed problem with plugin codecs using capability compare functions
 *
 * Revision 1.46  2004/06/30 12:31:09  rjongbloed
 * Rewrite of plug in system to use single global variable for all factories to avoid all sorts
 *   of issues with startup orders and Windows DLL multiple instances.
 *
 * Revision 1.45  2004/06/08 01:20:28  csoutheren
 * Provide backwards compatibility for applications using old capability API
 *
 * Revision 1.44  2004/06/01 05:47:58  csoutheren
 * Changed capability table to use abstract factory routines rather than internal linked list
 *
 * Revision 1.43  2004/05/13 12:49:32  rjongbloed
 * Fixed usage of the compare function in non-standard capabilities.
 *
 * Revision 1.42  2004/04/03 10:38:24  csoutheren
 * Added in initial cut at codec plugin code. Branches are for wimps :)
 *
 * Revision 1.41.2.1  2004/03/31 11:11:58  csoutheren
 * Initial public release of plugin codec code
 *
 * Revision 1.41  2004/03/02 11:48:14  rjongbloed
 * Fixed correct capability table matching when FindCapability with a mode change,
 *   uses different enum so needs translation table.
 *
 * Revision 1.40  2003/10/27 06:03:39  csoutheren
 * Added support for QoS
 *   Thanks to Henry Harrison of AliceStreet
 *
 * Revision 1.39  2003/06/06 02:13:10  rjongbloed
 * Changed non-standard capability semantics so can use C style strings as
 *   the embedded data block (ie automatically call strlen)
 *
 * Revision 1.38  2003/04/28 07:00:00  robertj
 * Fixed problem with compiler(s) not correctly initialising static globals
 *
 * Revision 1.37  2003/04/27 23:49:21  craigs
 * Fixed some comments and made list of registered codecs
 * available outside h323caps.cxx
 *
 * Revision 1.36  2002/11/09 04:24:01  robertj
 * Fixed minor documentation errors.
 *
 * Revision 1.35  2002/09/16 01:14:15  robertj
 * Added #define so can select if #pragma interface/implementation is used on
 *   platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan.
 *
 * Revision 1.34  2002/09/03 06:19:36  robertj
 * Normalised the multi-include header prevention ifdef/define symbol.
 *
 * Revision 1.33  2002/08/05 10:03:47  robertj
 * Cosmetic changes to normalise the usage of pragma interface/implementation.
 *
 * Revision 1.32  2002/05/29 03:55:17  robertj
 * Added protocol version number checking infrastructure, primarily to improve
 *   interoperability with stacks that are unforgiving of new features.
 *
 * Revision 1.31  2002/05/10 05:44:50  robertj
 * Added the max bit rate field to the data channel capability class.
 *
 * Revision 1.30  2002/01/22 06:25:02  robertj
 * Moved payload type to ancestor so any capability can adjust it on logical channel.
 *
 * Revision 1.29  2002/01/17 07:04:57  robertj
 * Added support for RFC2833 embedded DTMF in the RTP stream.
 *
 * Revision 1.28  2002/01/16 05:37:41  robertj
 * Added missing mode change functions on non standard capabilities.
 *
 * Revision 1.27  2002/01/09 00:21:36  robertj
 * Changes to support outgoing H.245 RequstModeChange.
 *
 * Revision 1.26  2001/12/22 01:44:05  robertj
 * Added more support for H.245 RequestMode operation.
 *
 * Revision 1.25  2001/10/24 01:20:34  robertj
 * Added code to help with static linking of H323Capability names database.
 *
 * Revision 1.24  2001/09/21 02:48:51  robertj
 * Added default implementation for PDU encode/decode for codecs
 *   that have simple integer as frames per packet.
 *
 * Revision 1.23  2001/09/11 10:21:40  robertj
 * Added direction field to capabilities, thanks Nick Hoath.
 *
 * Revision 1.22  2001/07/19 09:50:40  robertj
 * Added code for default session ID on data channel being three.
 *
 * Revision 1.21  2001/07/17 04:44:29  robertj
 * Partial implementation of T.120 and T.38 logical channels.
 *
 * Revision 1.20  2001/05/21 07:20:47  robertj
 * Removed redundent class name in declaration.
 *
 * Revision 1.19  2001/05/14 05:56:26  robertj
 * Added H323 capability registration system so can add capabilities by
 *   string name instead of having to instantiate explicit classes.
 *
 * Revision 1.18  2001/05/02 16:22:21  rogerh
 * Add IsAllow() for a single capability to check if it is in the
 * capabilities set. This fixes the bug where OpenH323 would accept
 * incoming H261 video even when told not to accept it.
 *
 * Revision 1.17  2001/03/16 23:00:21  robertj
 * Improved validation of codec selection against capability set, thanks Chris Purvis.
 *
 * Revision 1.16  2001/02/09 05:16:24  robertj
 * Added #pragma interface for GNU C++.
 *
 * Revision 1.15  2001/01/25 07:27:14  robertj
 * Major changes to add more flexible OpalMediaFormat class to normalise
 *   all information about media types, especially codecs.
 *
 * Revision 1.14  2001/01/09 23:05:22  robertj
 * Fixed inability to have 2 non standard codecs in capability table.
 *
 * Revision 1.13  2000/10/16 08:49:30  robertj
 * Added single function to add all UserInput capability types.
 *
 * Revision 1.12  2000/08/23 14:23:11  craigs
 * Added prototype support for Microsoft GSM codec
 *
 * Revision 1.11  2000/07/13 12:25:47  robertj
 * Fixed problems with fast start frames per packet adjustment.
 *
 * Revision 1.10  2000/07/10 16:01:50  robertj
 * Started fixing capability set merging, still more to do.
 *
 * Revision 1.9  2000/07/04 01:16:49  robertj
 * Added check for capability allowed in "combinations" set, still needs more done yet.
 *
 * Revision 1.8  2000/06/03 03:16:47  robertj
 * Fixed using the wrong capability table (should be connections) for some operations.
 *
 * Revision 1.7  2000/05/23 11:32:27  robertj
 * Rewrite of capability table to combine 2 structures into one and move functionality into that class
 *    allowing some normalisation of usage across several applications.
 * Changed H323Connection so gets a copy of capabilities instead of using endponts, allows adjustments
 *    to be done depending on the remote client application.
 *
 * Revision 1.6  2000/05/18 11:53:34  robertj
 * Changes to support doc++ documentation generation.
 *
 * Revision 1.5  2000/05/10 04:05:26  robertj
 * Changed capabilities so has a function to get name of codec, instead of relying on PrintOn.
 *
 * Revision 1.4  2000/05/02 04:32:24  robertj
 * Fixed copyright notice comment.
 *
 * Revision 1.3  2000/04/05 19:01:12  robertj
 * Added function so can change desired transmit packet size.
 *
 * Revision 1.2  2000/03/21 03:06:47  robertj
 * Changes to make RTP TX of exact numbers of frames in some codecs.
 *
 * Revision 1.1  1999/12/23 23:02:35  robertj
 * File reorganision for separating RTP from H.323 and creation of LID for VPB support.
 *
 */

#ifndef __OPAL_H323CAPS_H
#define __OPAL_H323CAPS_H

#ifdef P_USE_PRAGMA
#pragma interface
#endif


#include "codecs.h"
#include "channels.h"


/* The following classes have forward references to avoid including the VERY
   large header files for H225 and H245. If an application requires access
   to the protocol classes they can include them, but for simple usage their
   inclusion can be avoided.
 */
class PASN_Choice;
class H245_Capability;
class H245_DataType;
class H245_ModeElement;
class H245_AudioCapability;
class H245_AudioMode;
class H245_VideoCapability;
class H245_VideoMode;
class H245_DataApplicationCapability;
class H245_DataMode;
class H245_DataProtocolCapability;
class H245_H2250LogicalChannelParameters;
class H245_TerminalCapabilitySet;
class H245_NonStandardParameter;
class H323Connection;
class H323Capabilities;




class H323Capability : public PObject
{
  PCLASSINFO(H323Capability, PObject);

  public:
    H323Capability();

    Comparison Compare(const PObject & obj) const;

    void PrintOn(ostream & strm) const;

    enum MainTypes {
      e_Audio,
      e_Video,
      e_Data,
      e_UserInput,
      e_NumMainTypes
    };

    virtual MainTypes GetMainType() const = 0;

    virtual unsigned  GetSubType()  const = 0;

    virtual PString GetFormatName() const = 0;

    static H323Capability * Create(
      const PString & name    
    );

    static H323Capability * Create(
      H323EndPoint &,         
      const PString & name    
    )
    { return Create(name); }

    virtual unsigned GetDefaultSessionID() const;

    virtual void SetTxFramesInPacket(
      unsigned frames   
    );

    virtual unsigned GetTxFramesInPacket() const;

    virtual unsigned GetRxFramesInPacket() const;

    virtual H323Channel * CreateChannel(
      H323Connection & connection,    
      H323Channel::Directions dir,    
      unsigned sessionID,             
      const H245_H2250LogicalChannelParameters * param
    ) const = 0;

    virtual H323Codec * CreateCodec(
      H323Codec::Direction direction  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_Capability & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_DataType & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_ModeElement & pdu  
    ) const = 0;

    virtual BOOL OnReceivedPDU(
      const H245_Capability & pdu 
    );

    virtual BOOL OnReceivedPDU(
      const H245_DataType & pdu,  
      BOOL receiver               
    ) = 0;

    virtual BOOL IsNonStandardMatch(
      const H245_NonStandardParameter & param  
    ) const;

    virtual BOOL IsUsable(
      const H323Connection & connection
    ) const;

    enum CapabilityDirection {
      e_Unknown,
      e_Receive,
      e_Transmit,
      e_ReceiveAndTransmit,
      e_NoDirection,
      NumCapabilityDirections
    };

    CapabilityDirection GetCapabilityDirection() const { return capabilityDirection; }

    void SetCapabilityDirection(
      CapabilityDirection dir   
    ) { capabilityDirection = dir; }

    unsigned GetCapabilityNumber() const { return assignedCapabilityNumber; }

    void SetCapabilityNumber(unsigned num) { assignedCapabilityNumber = num; }

    RTP_DataFrame::PayloadTypes GetPayloadType() const { return rtpPayloadType; }

    virtual void AttachQoS(RTP_QOS *)
    {}

#if PTRACING
    friend ostream & operator<<(ostream & o , MainTypes t);
    friend ostream & operator<<(ostream & o , CapabilityDirection d);
#endif

  protected:
    unsigned assignedCapabilityNumber;  
    CapabilityDirection capabilityDirection;
    RTP_DataFrame::PayloadTypes rtpPayloadType;
};



class H323NonStandardCapabilityInfo
{
  public:
    typedef PObject::Comparison (*CompareFuncType)(struct PluginCodec_H323NonStandardCodecData *);

    H323NonStandardCapabilityInfo(
      CompareFuncType compareFunc,
      const BYTE * dataBlock,         
      PINDEX dataSize                 
    );

    H323NonStandardCapabilityInfo(
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,    
      PINDEX comparisonLength = P_MAX_INDEX    
    );

    H323NonStandardCapabilityInfo(
      const PString & oid,
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,
      PINDEX comparisonLength = P_MAX_INDEX
    );

    H323NonStandardCapabilityInfo(
      BYTE country,                  
      BYTE extension,                
      WORD maufacturer,              
      const BYTE * dataBlock,        
      PINDEX dataSize,               
      PINDEX comparisonOffset = 0,   
      PINDEX comparisonLength = P_MAX_INDEX  
    );

    virtual ~H323NonStandardCapabilityInfo();

    virtual BOOL OnSendingPDU(
      PBYTEArray & data  
    ) const;

    virtual BOOL OnReceivedPDU(
      const PBYTEArray & data  
    );

  protected:
    BOOL OnSendingNonStandardPDU(
      PASN_Choice & pdu,
      unsigned nonStandardTag
    ) const;
    BOOL OnReceivedNonStandardPDU(
      const PASN_Choice & pdu,
      unsigned nonStandardTag
    );

    PObject::Comparison CompareParam(
      const H245_NonStandardParameter & param
    ) const;
    PObject::Comparison CompareInfo(
      const H323NonStandardCapabilityInfo & obj
    ) const;
    PObject::Comparison CompareData(
      const PBYTEArray & data  
    ) const;

    PString    oid;
    BYTE       t35CountryCode;
    BYTE       t35Extension;
    WORD       manufacturerCode;
    PBYTEArray nonStandardData;
    PINDEX     comparisonOffset;
    PINDEX     comparisonLength;
    CompareFuncType compareFunc;
};


class H323RealTimeCapability : public H323Capability
{
  PCLASSINFO(H323RealTimeCapability, H323Capability);

  public:
    virtual H323Channel * CreateChannel(
      H323Connection & connection,    
      H323Channel::Directions dir,    
      unsigned sessionID,             
      const H245_H2250LogicalChannelParameters * param
    ) const;

    H323RealTimeCapability();
    H323RealTimeCapability(const H323RealTimeCapability &rtc);
    virtual ~H323RealTimeCapability();
    void AttachQoS(RTP_QOS * _rtpqos);

  protected:
    RTP_QOS * rtpqos;
};


class H323AudioCapability : public H323RealTimeCapability
{
  PCLASSINFO(H323AudioCapability, H323RealTimeCapability);

  public:
    H323AudioCapability(
      unsigned rxPacketSize, 
      unsigned txPacketSize  
    );

    virtual MainTypes GetMainType() const;

    virtual unsigned GetDefaultSessionID() const;

    virtual void SetTxFramesInPacket(
      unsigned frames   
    );

    virtual unsigned GetTxFramesInPacket() const;

    virtual unsigned GetRxFramesInPacket() const;

    virtual BOOL H245_H2250LogicalChannelParameters * param
    ) const = 0;

    virtual H323Codec * CreateCodec(
      H323Codec::Direction direction  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_Capability & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_DataType & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_ModeElement & pdu  
    ) const = 0;

    virtual BOOL OnReceivedPDU(
      const H245_Capability & pdu 
    );

    virtual BOOL OnReceivedPDU(
      const H245_DataType & pdu,  
      BOOL receiver               
    ) = 0;

    virtual BOOL IsNonStandardMatch(
      const H245_NonStandardParameter & param  
    ) const;

    virtual BOOL IsUsable(
      const H323Connection & connection
    ) const;

    enum CapabilityDirection {
      e_Unknown,
      e_Receive,
      e_Transmit,
      e_ReceiveAndTransmit,
      e_NoDirection,
      NumCapabilityDirections
    };

    CapabilityDirection GetCapabilityDirection() const { return capabilityDirection; }

    void SetCapabilityDirection(
      CapabilityDirection dir   
    ) { capabilityDirection = dir; }

    unsigned GetCapabilityNumber() const { return assignedCapabilityNumber; }

    void SetCapabilityNumber(unsigned num) { assignedCapabilityNumber = num; }

    RTP_DataFrame::PayloadTypes GetPayloadType() const { return rtpPayloadType; }

    virtual void AttachQoS(RTP_QOS *)
    {}

#if PTRACING
    friend ostream & operator<<(ostream & o , MainTypes t);
    friend ostream & operator<<(ostream & o , CapabilityDirection d);
#endif

  protected:
    unsigned assignedCapabilityNumber;  
    CapabilityDirection capabilityDirection;
    RTP_DataFrame::PayloadTypes rtpPayloadType;
};



class H323NonStandardCapabilityInfo
{
  public:
    typedef PObject::Comparison (*CompareFuncType)(struct PluginCodec_H323NonStandardCodecData *);

    H323NonStandardCapabilityInfo(
      CompareFuncType compareFunc,
      const BYTE * dataBlock,         
      PINDEX dataSize                 
    );

    H323NonStandardCapabilityInfo(
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,    
      PINDEX comparisonLength = P_MAX_INDEX    
    );

    H323NonStandardCapabilityInfo(
      const PString & oid,
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,
      PINDEX comparisonLength = P_MAX_INDEX
    );

    H323NonStandardCapabilityInfo(
      BYTE country,                  
      BYTE extension,                
      WORD maufacturer,              
      const BYTE * dataBlock,        
      PINDEX dataSize,               
      PINDEX comparisonOffset = 0,   
      PINDEX comparisonLength = P_MAX_INDEX  
    );

    virtual ~H323NonStandardCapabilityInfo();

    virtual BOOL OnSendingPDU(
      PBYTEArray & data  
    ) const;

    virtual BOOL OnReceivedPDU(
      const PBYTEArray & data  
    );

  protected:
    BOOL OnSendingNonStandardPDU(
      PASN_Choice & pdu,
      unsigned nonStandardTag
    ) const;
    BOOL OnReceivedNonStandardPDU(
      const PASN_Choice & pdu,
      unsigned nonStandardTag
    );

    PObject::Comparison CompareParam(
      const H245_NonStandardParameter & param
    ) const;
    PObject::Comparison CompareInfo(
      const H323NonStandardCapabilityInfo & obj
    ) const;
    PObject::Comparison CompareData(
      const PBYTEArray & data  
    ) const;

    PString    oid;
    BYTE       t35CountryCode;
    BYTE       t35Extension;
    WORD       manufacturerCode;
    PBYTEArray nonStandardData;
    PINDEX     comparisonOffset;
    PINDEX     comparisonLength;
    CompareFuncType compareFunc;
};


class H323RealTimeCapability : public H323Capability
{
  PCLASSINFO(H323RealTimeCapability, H323Capability);

  public:
    virtual H323Channel * CreateChannel(
      H323Connection & connection,    
      H323Channel::Directions dir,    
      unsigned sessionID,             
      const H245_H2250LogicalChannelParameters * param
    ) const;

    H323RealTimeCapability();
    H323RealTimeCapability(const H323RealTimeCapability &rtc);
    virtual ~H323RealTimeCapability();
    void AttachQoS(RTP_QOS * _rtpqos);

  protected:
    RTP_QOS * rtpqos;
};


class H323AudioCapability : public H323RealTimeCapability
{
  PCLASSINFO(H323AudioCapability, H323RealTimeCapability);

  public:
    H323AudioCapability(
      unsigned rxPacketSize, 
      unsigned txPacketSize  
    );

    virtual MainTypes GetMainType() const;

    virtual unsigned GetDefaultSessionID() const;

    virtual void SetTxFramesInPacket(
      unsigned frames   
    );

    virtual unsigned GetTxFramesInPacket() const;

    virtual unsigned GetRxFramesInPacket() const;

    virtual BOOL H245_H2250LogicalChannelParameters * param
    ) const = 0;

    virtual H323Codec * CreateCodec(
      H323Codec::Direction direction  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_Capability & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_DataType & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_ModeElement & pdu  
    ) const = 0;

    virtual BOOL OnReceivedPDU(
      const H245_Capability & pdu 
    );

    virtual BOOL OnReceivedPDU(
      const H245_DataType & pdu,  
      BOOL receiver               
    ) = 0;

    virtual BOOL IsNonStandardMatch(
      const H245_NonStandardParameter & param  
    ) const;

    virtual BOOL IsUsable(
      const H323Connection & connection
    ) const;

    enum CapabilityDirection {
      e_Unknown,
      e_Receive,
      e_Transmit,
      e_ReceiveAndTransmit,
      e_NoDirection,
      NumCapabilityDirections
    };

    CapabilityDirection GetCapabilityDirection() const { return capabilityDirection; }

    void SetCapabilityDirection(
      CapabilityDirection dir   
    ) { capabilityDirection = dir; }

    unsigned GetCapabilityNumber() const { return assignedCapabilityNumber; }

    void SetCapabilityNumber(unsigned num) { assignedCapabilityNumber = num; }

    RTP_DataFrame::PayloadTypes GetPayloadType() const { return rtpPayloadType; }

    virtual void AttachQoS(RTP_QOS *)
    {}

#if PTRACING
    friend ostream & operator<<(ostream & o , MainTypes t);
    friend ostream & operator<<(ostream & o , CapabilityDirection d);
#endif

  protected:
    unsigned assignedCapabilityNumber;  
    CapabilityDirection capabilityDirection;
    RTP_DataFrame::PayloadTypes rtpPayloadType;
};



class H323NonStandardCapabilityInfo
{
  public:
    typedef PObject::Comparison (*CompareFuncType)(struct PluginCodec_H323NonStandardCodecData *);

    H323NonStandardCapabilityInfo(
      CompareFuncType compareFunc,
      const BYTE * dataBlock,         
      PINDEX dataSize                 
    );

    H323NonStandardCapabilityInfo(
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,    
      PINDEX comparisonLength = P_MAX_INDEX    
    );

    H323NonStandardCapabilityInfo(
      const PString & oid,
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,
      PINDEX comparisonLength = P_MAX_INDEX
    );

    H323NonStandardCapabilityInfo(
      BYTE country,                  
      BYTE extension,                
      WORD maufacturer,              
      const BYTE * dataBlock,        
      PINDEX dataSize,               
      PINDEX comparisonOffset = 0,   
      PINDEX comparisonLength = P_MAX_INDEX  
    );

    virtual ~H323NonStandardCapabilityInfo();

    virtual BOOL OnSendingPDU(
      PBYTEArray & data  
    ) const;

    virtual BOOL OnReceivedPDU(
      const PBYTEArray & data  
    );

  protected:
    BOOL OnSendingNonStandardPDU(
      PASN_Choice & pdu,
      unsigned nonStandardTag
    ) const;
    BOOL OnReceivedNonStandardPDU(
      const PASN_Choice & pdu,
      unsigned nonStandardTag
    );

    PObject::Comparison CompareParam(
      const H245_NonStandardParameter & param
    ) const;
    PObject::Comparison CompareInfo(
      const H323NonStandardCapabilityInfo & obj
    ) const;
    PObject::Comparison CompareData(
      const PBYTEArray & data  
    ) const;

    PString    oid;
    BYTE       t35CountryCode;
    BYTE       t35Extension;
    WORD       manufacturerCode;
    PBYTEArray nonStandardData;
    PINDEX     comparisonOffset;
    PINDEX     comparisonLength;
    CompareFuncType compareFunc;
};


class H323RealTimeCapability : public H323Capability
{
  PCLASSINFO(H323RealTimeCapability, H323Capability);

  public:
    virtual H323Channel * CreateChannel(
      H323Connection & connection,    
      H323Channel::Directions dir,    
      unsigned sessionID,             
      const H245_H2250LogicalChannelParameters * param
    ) const;

    H323RealTimeCapability();
    H323RealTimeCapability(const H323RealTimeCapability &rtc);
    virtual ~H323RealTimeCapability();
    void AttachQoS(RTP_QOS * _rtpqos);

  protected:
    RTP_QOS * rtpqos;
};


class H323AudioCapability : public H323RealTimeCapability
{
  PCLASSINFO(H323AudioCapability, H323RealTimeCapability);

  public:
    H323AudioCapability(
      unsigned rxPacketSize, 
      unsigned txPacketSize  
    );

    virtual MainTypes GetMainType() const;

    virtual unsigned GetDefaultSessionID() const;

    virtual void SetTxFramesInPacket(
      unsigned frames   
    );

    virtual unsigned GetTxFramesInPacket() const;

    virtual unsigned GetRxFramesInPacket() const;

    virtual BOOL H245_H2250LogicalChannelParameters * param
    ) const = 0;

    virtual H323Codec * CreateCodec(
      H323Codec::Direction direction  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_Capability & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_DataType & pdu  
    ) const = 0;

    virtual BOOL OnSendingPDU(
      H245_ModeElement & pdu  
    ) const = 0;

    virtual BOOL OnReceivedPDU(
      const H245_Capability & pdu 
    );

    virtual BOOL OnReceivedPDU(
      const H245_DataType & pdu,  
      BOOL receiver               
    ) = 0;

    virtual BOOL IsNonStandardMatch(
      const H245_NonStandardParameter & param  
    ) const;

    virtual BOOL IsUsable(
      const H323Connection & connection
    ) const;

    enum CapabilityDirection {
      e_Unknown,
      e_Receive,
      e_Transmit,
      e_ReceiveAndTransmit,
      e_NoDirection,
      NumCapabilityDirections
    };

    CapabilityDirection GetCapabilityDirection() const { return capabilityDirection; }

    void SetCapabilityDirection(
      CapabilityDirection dir   
    ) { capabilityDirection = dir; }

    unsigned GetCapabilityNumber() const { return assignedCapabilityNumber; }

    void SetCapabilityNumber(unsigned num) { assignedCapabilityNumber = num; }

    RTP_DataFrame::PayloadTypes GetPayloadType() const { return rtpPayloadType; }

    virtual void AttachQoS(RTP_QOS *)
    {}

#if PTRACING
    friend ostream & operator<<(ostream & o , MainTypes t);
    friend ostream & operator<<(ostream & o , CapabilityDirection d);
#endif

  protected:
    unsigned assignedCapabilityNumber;  
    CapabilityDirection capabilityDirection;
    RTP_DataFrame::PayloadTypes rtpPayloadType;
};



class H323NonStandardCapabilityInfo
{
  public:
    typedef PObject::Comparison (*CompareFuncType)(struct PluginCodec_H323NonStandardCodecData *);

    H323NonStandardCapabilityInfo(
      CompareFuncType compareFunc,
      const BYTE * dataBlock,         
      PINDEX dataSize                 
    );

    H323NonStandardCapabilityInfo(
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,    
      PINDEX comparisonLength = P_MAX_INDEX    
    );

    H323NonStandardCapabilityInfo(
      const PString & oid,
      const BYTE * dataBlock,         
      PINDEX dataSize,                
      PINDEX comparisonOffset = 0,
      PINDEX comparisonLength = P_MAX_INDEX
    );

    H323NonStandardCapabilityInfo(
      BYTE country,                  
      BYTE extension,                
      WORD maufacturer,              
      const BYTE * dataBlock,        
      PINDEX dataSize,               
      PINDEX comparisonOffset = 0,   
      PINDEX comparisonLength = P_MAX_INDEX  
    );

    virtual ~H323NonStandardCapabilityInfo();

    virtual BOOL OnSendingPDU(
      PBYTEArray & data  
    ) const;

    virtual BOOL OnReceivedPDU(
      const PBYTEArray & data  
    );

  protected:
    BOOL OnSendingNonStandardPDU(
      PASN_Choice & pdu,
      unsigned nonStandardTag
    ) const;
    BOOL OnReceivedNonStandardPDU(
      const PASN_Choice & pdu,
      unsigned nonStandardTag
    );

    PObject::Comparison CompareParam(
      const H245_NonStandardParameter & param
    ) const;
    PObject::Comparison CompareInfo(
      const H323NonStandardCapabilityInfo & obj
    ) const;
    PObject::Comparison CompareData(
      const PBYTEArray & data  
    ) const;

    PString    oid;
    BYTE       t35CountryCode;
    BYTE       t35Extension;
    WORD       manufacturerCode;
    PBYTEArray nonStandardData;
    PINDEX     comparisonOffset;
    PINDEX     comparisonLength;
    CompareFuncType compareFunc;
};


class H323RealTimeCapability : public H323Capability
{
  PCLASSINFO(H323RealTimeCapability, H323Capability);

  public:
    virtual H323Channel * CreateChannel(
      H323Connection & connection,    
      H323Channel::Directions dir,    
      unsigned sessionID,             
      const H245_H2250LogicalChannelParameters * param
    ) const;

    H323RealTimeCapability();
    H323RealTimeCapability(const H323RealTimeCapability &rtc);
    virtual ~H323RealTimeCapability();
    void AttachQoS(RTP_QOS * _rtpqos);

  protected:
    RTP_QOS * rtpqos;
};


class H323AudioCapability : public H323RealTimeCapability
{
  PCLASSINFO(H323AudioCapability, H323RealTimeCapability);

  public:
    H323AudioCapability(
      unsigned rxPacke