使用jrtplib传输H.264视频文件（3）

转自：http://blog.csdn.net/liushu1231/article/details/9203643

本文所有内容均为原创，转载请注明出处！

介绍如何发送h264，下面我们介绍下如何接收h264文件。

其中主要关注的就是被拆分的数据包的重组，下面的代码中有详尽的注释。

 class CRTPReceiver : public RTPSession
 {
 protected:
     void OnPollThreadStep();
     void ProcessRTPPacket(const RTPSourceData &srcdat,const RTPPacket &rtppack);
     void OnRTCPCompoundPacket(RTCPCompoundPacket *pack,const RTPTime &receivetime,const RTPAddress *senderaddress);

 public:
     CThreadSafeArray m_ReceiveArray;
     void InitBufferSize();

 private:
     CVideoData* m_pVideoData;
     unsigned char m_buffer[BUFFER_SIZE];
     int m_current_size;
 };

 void CRTPReceiver::InitBufferSize()
 {
     m_ReceiveArray.SetMemberSize(BUFFER_SIZE);
     m_pVideoData = new CVideoData();
     memset(m_buffer,0,BUFFER_SIZE);
     m_current_size = 0;
 }

 void CRTPReceiver::OnRTCPCompoundPacket(RTCPCompoundPacket *pack,const RTPTime &receivetime,const RTPAddress *senderaddress)
 {
     //std::cout<<"Got RTCP packet from: "<<senderaddress<<std::endl;
 }


 void CRTPReceiver::OnPollThreadStep()
 {
     BeginDataAccess();

     // check incoming packets
     if (GotoFirstSourceWithData())
     {
         do
         {
             RTPPacket *pack;
             RTPSourceData *srcdat;

             srcdat = GetCurrentSourceInfo();

             while ((pack = GetNextPacket()) != NULL)
             {
                 ProcessRTPPacket(*srcdat,*pack);
                 DeletePacket(pack);
             }
         } while (GotoNextSourceWithData());
     }

     EndDataAccess();
 }

 void CRTPReceiver::ProcessRTPPacket(const RTPSourceData &srcdat,const RTPPacket &rtppack)
 {
     // You can inspect the packet and the source's info here
     //std::cout<<"Packet type: "<<rtppack.GetPayloadType()<<std::endl;
     //std::cout<<"Packet says: "<<(char *)rtppack.GetPayloadData()<<std::endl;
     //test RTCP packet
     /*int status = this->SendRTCPAPPPacket(0,(uint8_t*)&("123"),(void*)&("hel"),4);
     checkerror(status);*/

     if(rtppack.GetPayloadType() == H264)
     {
         //std::cout<<"Got H264 packet：êo " << rtppack.GetExtendedSequenceNumber() << " from SSRC " << srcdat.GetSSRC() <<std::endl;
         if(rtppack.HasMarker())//如果是最后一包则进行组包
         {
             m_pVideoData->m_lLength = m_current_size + rtppack.GetPayloadLength();//得到数据包总的长度
             memcpy(m_pVideoData->m_pBuffer,m_buffer,m_current_size);
             memcpy(m_pVideoData->m_pBuffer + m_current_size ,rtppack.GetPayloadData(),rtppack.GetPayloadLength());

             m_ReceiveArray.Add(m_pVideoData);//添加到接收队列

             memset(m_buffer,0,m_current_size);//清空缓存，为下次做准备
             m_current_size = 0;
         }
         else//放入缓冲区，在此必须确保有序
         {
             unsigned char* p = rtppack.GetPayloadData();


             memcpy(m_buffer + m_current_size,rtppack.GetPayloadData(),rtppack.GetPayloadLength());
             m_current_size += rtppack.GetPayloadLength();
         }
     }

 }


 void StartReceive()
 {
     /*CRTPReceiver sess;*/
     sess.InitBufferSize();
     std::string ipstr;
     int status;

     // Now, we'll create a RTP session, set the destination
     // and poll for incoming data.
     RTPUDPv4TransmissionParams transparams;
     RTPSessionParams sessparams;

     // IMPORTANT: The local timestamp unit MUST be set, otherwise
     //            RTCP Sender Report info will be calculated wrong
     // In this case, we'll be just use 9000 samples per second.
     sessparams.SetOwnTimestampUnit(1.0/9000.0);

     transparams.SetPortbase(PORT_BASE);
     status = sess.Create(sessparams,&transparams);
     checkerror(status);

     uint32_t dst_ip = inet_addr(DST_IP);
     dst_ip = ntohl(dst_ip);
     RTPIPv4Address addr(dst_ip,DST_PORT);
     status = sess.AddDestination(addr);

     checkerror(status);
 }

 int main(int argc, char* argv[])
 {
     WSADATA dat;
     WSAStartup(MAKEWORD(2,2),&dat);
     StartReceive();
     RTPTime::Wait(RTPTime(3,0));
     return 0;
 }

至此，使用jrtplib传输h264全部完成。