使用jrtplib（RTP）传输H.264视频文件（2）

转自http://blog.csdn.net/liushu1231/article/details/9203593

上一篇我们介绍了RTP协议的一些基本知识，下面我们介绍如何使用jrtplib这个库传输H264编码。

JRTP传输：
好了，下面是我写的使用JRTP进行发送H264数据包的例子，具体解释可以看注释。发送端也可以接收接收端发送过来的RTCP数据包。
#define MAX_RTP_PKT_LENGTH 1360
#define H264               96

bool CheckError(int rtperr);


class CRTPSender :
    public RTPSession
{
public:
    CRTPSender(void);
    ~CRTPSender(void);

protected:
    void OnAPPPacket(RTCPAPPPacket *apppacket,const RTPTime &receivetime,const RTPAddress *senderaddress);
    void OnBYEPacket(RTPSourceData *srcdat);
    void OnBYETimeout(RTPSourceData *srcdat);
public:
    void SendH264Nalu(unsigned char* m_h264Buf,int buflen);
    void SetParamsForSendingH264();
};


bool CheckError(int rtperr)
{
    if (rtperr < 0)
    {
        std::cout<<”ERROR: ”<
        return false;
    }
    return true;
}


CRTPSender::CRTPSender(void)
{
}


CRTPSender::~CRTPSender(void)
{
}

void CRTPSender::OnAPPPacket(RTCPAPPPacket *apppacket,const RTPTime &receivetime,const RTPAddress *senderaddress)
{//收到RTCP APP数据
    std::cout<<”Got RTCP packet from: ”<
    std::cout<<”Got RTCP subtype: ”<GetSubType()<
    std::cout<<”Got RTCP data: ”<<(char *)apppacket->GetAPPData()<
    return ;
}

void CRTPSender::SendH264Nalu(unsigned char* m_h264Buf,int buflen)
{
    unsigned char *pSendbuf; //发送数据指针
    pSendbuf = m_h264Buf;

    //去除前导码0x000001 或者0x00000001
    //if( 0x01 == m_h264Buf[2] )
    //{
    //  pSendbuf = &m_h264Buf[3];
    //  buflen -= 3;
    //}
    //else
    //{
    //  pSendbuf = &m_h264Buf[4];
    //  buflen -= 4;
    //}


    char sendbuf[1430];   //发送的数据缓冲
    memset(sendbuf,0,1430);

    int status;

    printf(”send packet length %d \n”,buflen);

    if ( buflen <= MAX_RTP_PKT_LENGTH )
    {
        memcpy(sendbuf,pSendbuf,buflen);
        status = this->SendPacket((void *)sendbuf,buflen);

        CheckError(status);

    }
    else if(buflen > MAX_RTP_PKT_LENGTH)
    {
        //设置标志位Mark为0
        this->SetDefaultMark(false);
        //printf(“buflen = %d\n”,buflen);
        //得到该需要用多少长度为MAX_RTP_PKT_LENGTH字节的RTP包来发送
        int k=0,l=0;
        k = buflen / MAX_RTP_PKT_LENGTH;
        l = buflen % MAX_RTP_PKT_LENGTH;
        int t=0;//用指示当前发送的是第几个分片RTP包

        char nalHeader = pSendbuf[0]; // NALU 头ª¡¤
        while( t < k || ( t==k && l>0 ) )
        {
            if( (0 == t ) || ( t//第一包到最后包的前一包
            {
                /*sendbuf[0] = (nalHeader & 0x60)|28;
                sendbuf[1] = (nalHeader & 0x1f);
                if ( 0 == t )
                {
                    sendbuf[1] |= 0x80;
                }
                memcpy(sendbuf+2,&pSendbuf[t*MAX_RTP_PKT_LENGTH],MAX_RTP_PKT_LENGTH);
                status = this->SendPacket((void *)sendbuf,MAX_RTP_PKT_LENGTH+2);*/
                memcpy(sendbuf,&pSendbuf[t*MAX_RTP_PKT_LENGTH],MAX_RTP_PKT_LENGTH);
                status = this->SendPacket((void *)sendbuf,MAX_RTP_PKT_LENGTH);
                CheckError(status);
                t++;
            }
            //最后一包
            else if( ( k==t && l>0 ) || ( t== (k-1) && l==0 ))
            {
                //设置标志位Mark为1
                this->SetDefaultMark(true);

                int iSendLen;
                if ( l > 0)
                {
                    iSendLen = buflen - t*MAX_RTP_PKT_LENGTH;
                }
                else
                    iSendLen = MAX_RTP_PKT_LENGTH;

                //sendbuf[0] = (nalHeader & 0x60)|28;
                //sendbuf[1] = (nalHeader & 0x1f);
                //sendbuf[1] |= 0x40;

                //memcpy(sendbuf+2,&pSendbuf[t*MAX_RTP_PKT_LENGTH],iSendLen);
                //status = this->SendPacket((void *)sendbuf,iSendLen+2);

                memcpy(sendbuf,&pSendbuf[t*MAX_RTP_PKT_LENGTH],iSendLen);
                status = this->SendPacket((void *)sendbuf,iSendLen);

                CheckError(status);
                t++;
            }
        }
    }
}


void CRTPSender::SetParamsForSendingH264()
{
    this->SetDefaultPayloadType(H264);//设置传输类型
    this->SetDefaultMark(true);      //设置位
    this->SetTimestampUnit(1.0/9000.0); //设置采样间隔
    this->SetDefaultTimestampIncrement(3600);//设置时间戳增加间隔
}

void CRTPSender::OnBYEPacket(RTPSourceData *srcdat)
{

}

void CRTPSender::OnBYETimeout(RTPSourceData *srcdat)
{

}


Main.cpp  在上一篇博客中的编码之后进行传输

#define SSRC           100

#define DEST_IP_STR   “192.168.1.252”
#define DEST_PORT     1234
#define BASE_PORT     2222

int iNal   = 0;
x264_nal_t* pNals = NULL;


void SetRTPParams(CRTPSender& sess,uint32_t destip,uint16_t destport,uint16_t baseport)
{
    int status;
    //RTP+RTCP库初始化SOCKET环境
    RTPUDPv4TransmissionParams transparams;
    RTPSessionParams sessparams;
    sessparams.SetOwnTimestampUnit(1.0/9000.0); //时间戳单位
    sessparams.SetAcceptOwnPackets(true);   //接收自己发送的数据包
    sessparams.SetUsePredefinedSSRC(true);  //设置使用预先定义的SSRC
    sessparams.SetPredefinedSSRC(SSRC);     //定义SSRC

    transparams.SetPortbase(baseport);

    status = sess.Create(sessparams,&transparams);
    CheckError(status);

    destip = ntohl(destip);
    RTPIPv4Address addr(destip,destport);
    status = sess.AddDestination(addr);
    CheckError(status);

    //为发送H264包设置参数
    //sess.SetParamsForSendingH264();

}
bool InitSocket()
{
    int Error;
    WORD VersionRequested;
    WSADATA WsaData;
    VersionRequested=MAKEWORD(2,2);
    Error=WSAStartup(VersionRequested,&WsaData); //启动WinSock2
    if(Error!=0)
    {
        printf(”Error:Start WinSock failed!\n”);
        return false;
    }
    else
    {
        if(LOBYTE(WsaData.wVersion)!=2||HIBYTE(WsaData.wHighVersion)!=2)
        {
            printf(”Error:The version is WinSock2!\n”);
            WSACleanup();
            return false;
        }

    }
    return true;
}

void CloseSocket(CRTPSender sess)
{
    //发送一个BYE包离开会话最多等待秒钟超时则不发送
    sess.BYEDestroy(RTPTime(3,0),0,0);
    WSACleanup();
}

int main(int argc, char** argv)
{
    InitSocket();
    CRTPSender sender;
    string destip_str = ”127.0.0.1”;
    uint32_t dest_ip = inet_addr(destip_str.c_str());

    SetRTPParams(sender,dest_ip,DEST_PORT,BASE_PORT);
    sender.SetParamsForSendingH264();

    //…x264设置参数等步骤，具体参见上篇博客
    for(int i = 0; i < nFrames ; i++ )
    {
        //读取一帧
        read_frame_y4m(pPicIn,(hnd_t*)y4m_hnd,i);
        if( i ==0 )
            pPicIn->i_pts = i;
        else
            pPicIn->i_pts = i - 1;

        //编码
        int frame_size = x264_encoder_encode(pX264Handle,&pNals,&iNal,pPicIn,pPicOut);

        if(frame_size >0)
        {

            for (int i = 0; i < iNal; ++i)
            {//将编码数据写入文件t
                //fwrite(pNals[i].p_payload, 1, pNals[i].i_payload, pFile);
                //发送编码文件
                sender.SendH264Nalu(pNals[i].p_payload,pNals[i].i_payload);
                RTPTime::Wait(RTPTime(1,0));
            }
        }
    }

     CloseSocket(sender);
    //一些清理工作…
}