为什么在接收rtsp网络视频流总是接收不到数据的！

记录在案 2011-08-30 05:23:45

为什么在接收rtsp网络视频流总是超时接收不到数据的！



	int sockin, sc1, sc2;

	sockaddr_in addr;

	char *buf, *szcmd, *url;

	char szip[32];

	int nlen, iret, iport;

	int ip1, ip2;

	long lret;

	//初始化变量　

	FD_ZERO(&rfdsock);

	fp = fopen("1.txt", "w+");

	//分配缓冲区

	nlen = 10240;

	buf = (char*)malloc(nlen);

	//定义要连接的url

	url = "rtsp://192.168.1.66:554/channel0";

	//初始化sock

	InitSocket();

	//分析url请求，取出ip，端口

	lret = PraseURL(url, szip, &iport);

	//初始化与服务器连接的socket

	sockin = InitTCPSocket(0);

	//与服务器连接

	addr.sin_family = AF_INET;

	addr.sin_port = htons(iport);

	addr.sin_addr.s_addr = inet_addr(szip);

	iret = connect(sockin,(struct sockaddr*)&addr, sizeof addr);

	//发送option命令

	szcmd = GetOptionCmd(url);

	lret = SendRTSPCmd(sockin, "OPTIONS",szcmd);

	free(szcmd);

	lret = ReadSocket(sockin, buf, nlen,100);

	//发送DESCRIBE命令

	szcmd = GetDescribeCmd(url);

	lret = SendRTSPCmd(sockin, "DESCRIBE", szcmd);

	free(szcmd);

	lret = ReadSocket(sockin, buf, nlen, 100);

	//解析Response

	lret = PraseDescribeCmd((const char*)buf);

	//创建客户端接收端口

	sc1 = InitUDPSocket(NULL, 6544);

	sc2 = InitUDPSocket(NULL, 6545);

	//将sock加入到要等待的队列

	FD_SET(sc1, &rfdsock );

	FD_SET(sc2, &rfdsock);

	lret = GetSokcetPort(sc1, &ip1);

	lret = GetSokcetPort(sc2, &ip2);

	//发送Setup命令，告诉服务器客户端的接受数据的端口

	szcmd = GetSetupCmd(url, ip1, ip2);

	//告诉服务器客户端的端口

	lret = SendRTSPCmd(sockin, "SETUP", szcmd);

	free(szcmd);

	lret = ReadSocket(sockin, buf, nlen, 100);

	//解析Response返回的命令串

	lret = PraseSetupCmd(buf, szip);

	char *session, *srange;

	session = szip;

	//发送PLAY命令

	srange = "Range: npt=0.000-39.471\r\n";

	szcmd = GetPlayCmd(url, session, srange);

	lret = SendRTSPCmd(sockin, "PLAY", szcmd);

	free(szcmd);

	lret = ReadSocket(sockin, buf, nlen, 100);

	timeval tv;

	fd_set fr;

	int i;

	tv.tv_sec = 20;

	tv.tv_usec = 0;

	struct sockaddr_in addr2;

	int addrlen;

	addrlen = sizeof addr;

	//将数据写到文件中去

	FILE *ffp;

	ffp = fopen("receive.m4e", "wb");

	//开始接受数据了

	while(true)

	{

		fr = rfdsock;

		/*此处在接收到一定时候后，超时 */

		lret = select(0, &fr, NULL, NULL, &tv); 

		if(lret == SOCKET_ERROR)

		{

			break;

		}

		else if(lret >0)

		{

			//判断是哪个socket可以读取数据了

			for(i = 0; i< 2;i ++)

			{

				if(FD_ISSET(rfdsock.fd_array[i], &fr)

					&& FD_ISSET(rfdsock.fd_array[i], &rfdsock))

				{

					lret = recvfrom(rfdsock.fd_array[i], buf, nlen,0, (struct sockaddr*)&addr2, &addrlen );

					if(lret > 0 && ffp)

					{

						fwrite(buf+12, 1, lret-12, ffp);

					}

					else if(lret == SOCKET_ERROR)

					{

						break;

					}

				}

			}



		}

		else if(lret == 0)

			break;

	}

	fclose(ffp);



	//退出后的清理工作

	closesocket(sockin);

	closesocket(sc1);

	closesocket(sc2);



	fwrite("\r\nend", 1, 5, fp);

	fclose(fp);