学步园

发送端是嵌入式开发板，芯片为ADI的blackfin系列ADSP-BF537

此次发布的发送程序和接收程序是经过测试的。

以下为发送端程序，注明下以LOCALTEST宏标注的是自发自收功能模块，现已#undef LOCALTEST了。同时在自发自收部分，我使用了Poll()，说明我没有采用Jthread库来实现多线程，而直接用单线程，即SendPacket一个数据包后，后面用Poll()来轮询是否有数据包到达。如果使用了Jthread库，则Poll()就不用了。

 // JRTPLIB sender on ADSP-BF537
 // wangsu820@163.com  2008-06-30
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iostream>

#include <sys/socket.h>
 
#include "include/rtpsession.h"
#include "include/rtpsessionparams.h"
#include "include/rtpudpv4transmitter.h"
#include "include/rtpipv4address.h"
#include "include/rtperrors.h"

//调试信息功能

#define DEBUG
//本地测试功能
#undef LOCALTEST

#ifdef LOCALTEST
#include "include/rtppacket.h"
typedef unsigned char uint8_t;
//blackfin
typedef unsigned long size_t;  
#endif

void checkerror( int errorcode )
{
  if( errorcode < 0 )
  {
    std::cout<< "ERROR:" << RTPGetErrorString( errorcode ) << std::endl;
    exit( -1 ); 
  } 
}

void usage( void )
{
  std::cout << "Usage: ./bf537_send DestinationIPAddress DestinationPort" << std::endl; 
}

int main( int argc, char **argv )
{
  RTPSession rtpsess;
  RTPSessionParams sessionparams;
  RTPUDPv4TransmissionParams transparams;
  unsigned long destip;
  int destport, srcport = 8000;
  int packetnum;
  int status, i;
  
  //命令行参数解析
  if( argc != 3 )
  {
    usage();
    return -1;
  }
  
  destip = inet_addr( argv[1] ); 
  if( INADDR_NONE == destip )
  {
    std::cerr << "Bad IP Address" << std::endl;
    return -1;
  } 
  destip = ntohl( destip );
  std::cout << "Destination IP Address:"
       << argv[1]
       << std::endl;

  destport = atoi( argv[2] );
  std::cout << "Destination Port:"
       << destport
       << std::endl;
  
  std::cout << "How many packets you want to send?" << std::endl;
  std::cin >> packetnum;
    
  //创建会话
  sessionparams.SetOwnTimestampUnit( 1.0 / 8000.0 );
#ifdef LOCALTEST
  sessionparams.SetAcceptOwnPackets( true );
  std::cout << "LOCALTEST,you can receive your sent data" << std::endl;
#endif  
  transparams.SetPortbase( srcport );
  status = rtpsess.Create( sessionparams, &transparams );
#ifdef DEBUG
  std::cout << "check if Create Session error" << std::endl;
#endif  
  checkerror( status );
  
  //将目标地址添加到发送地址列表中
  RTPIPv4Address addr( destip, destport );
  status = rtpsess.AddDestination( addr );
#ifdef DEBUG
  std::cout << "check if AddDestination error" << std::endl;
#endif   
  checkerror( status );
  
  //设置RTP包的默认参数
  rtpsess.SetDefaultPayloadType( 0 );
  rtpsess.SetDefaultMark( false );
  rtpsess.SetDefaultTimestampIncrement( 10 );
  
   //循环发送数据
   for( i = 1; i <= packetnum; i++ )
   {
     printf( "Send packet [%d/%d]......", i, packetnum );
     status = rtpsess.SendPacket( ( void * )"1234567890", 10 );
     checkerror( status );
     printf( "OK/n" );
#ifdef LOCALTEST
    //本地自己接收
    rtpsess.BeginDataAccess();
#ifdef DEBUG
    std::cout << "localhost begin to receive..." << std::endl;
#endif    
    if( rtpsess.GotoFirstSourceWithData() )
    {
#ifdef DEBUG
      std::cout << "Go to First Source With Data..." << std::endl;
#endif     
      do
      {
        RTPPacket *rtppack;
        while( ( rtppack = rtpsess.GetNextPacket() ) != NULL )
        {
          //printf( "Got packet/n" );
          std::cout << "Got packet,"
               << "data is:"
               <<
rtppack->GetPayloadData()
               << "length is "
               <<
rtppack->GetPayloadLength()
               << std::endl;
          rtpsess.DeletePacket( rtppack );
        }
      }while( rtpsess.GotoNextSourceWithData() );
    } 
    rtpsess.EndDataAccess();
    //因为不使用poll thread,所以在接和发RTCP包时,该函数需被调用
    status = rtpsess.Poll();
    checkerror( status );
#endif //end LOCALTEST
    RTPTime::Wait( RTPTime( 1, 0 ) );  
   }//end for()
   
   //离开会话
   rtpsess.BYEDestroy( RTPTime( 10, 0 ), 0, 0 );
#ifdef DEBUG
  std::cout << "GoodBye RTP Session" << std::endl;
#endif      
  return 0; 
}

转自 http://blog.sina.com.cn/s/blog_4e87ac6e01009x8q.html