// g711.c  //  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  

#include <memory.h>  

  

#include <netdb.h>  

#include <time.h>  

#include <sys/types.h>  

#include <netinet/in.h>  

#include <sys/socket.h>  

#include <arpa/inet.h>  

#include <unistd.h>    //close()  

#define DEST_PORT  8888  

#define DEST_IP "192.168.1.18"  

  

  

typedef struct  

{  

      

    unsigned char csrc_len:4;          

    unsigned char extension:1;         

    unsigned char padding:1;           

    unsigned char version:2;           

      

    unsigned char payload:7;           

    unsigned char marker:1;            

      

    unsigned short seq_no;  

      

    unsigned  long timestamp;  

      

    unsigned long ssrc;                

} RTP_FIXED_HEADER;  

  

  

int main(int argc, char* argv[])  

{  

    FILE *file_g711 = NULL;  

    int ret;  

    int M_bit;  

    M_bit = 1;  

  

    char sendbuf[1500];  

    memset(sendbuf,0,1500);  

    unsigned short seq_num = 0;  

    RTP_FIXED_HEADER        *rtp_hdr;  

  

    int    socket1;  

    struct sockaddr_in server;  

    int len = sizeof(server);  

    float framerate = 25;  

    unsigned int timestamp_increse = 0,ts_current = 0;  

    timestamp_increse = 160;  

  

    server.sin_family = AF_INET;  

    server.sin_port = htons(DEST_PORT);  

    server.sin_addr.s_addr = inet_addr(DEST_IP);  

    socket1 = socket(AF_INET,SOCK_DGRAM,0);  

    connect(socket1, (struct sockaddr *)&server, len) ;//申请UDP套接字  

  

    file_g711 = fopen("test.g711","rb");  

    if(file_g711 == NULL)  

    {  

        printf("fopen error!\n");  

    }  

    printf("g711 open successfully!\n");  

  

  

    while((ret = fread(&sendbuf[12],sizeof(char),160,file_g711)) > 0)  

    {  

    rtp_hdr =(RTP_FIXED_HEADER*)&sendbuf[0];  

    //设置RTP HEADER，  

    rtp_hdr->payload     = 0;  //负载类型号，  

    rtp_hdr->version     = 2;  //版本号，此版本固定为2  

    if(1 == M_bit)  

    {  

            rtp_hdr->marker    = 1;   //标志位，由具体协议规定其值。  

            M_bit = 0;  

        printf("M_bit = 1\n");  

    }  

    else  

    {  

        rtp_hdr->marker    = 0;   //标志位，由具体协议规定其值。  

    }  

  

        rtp_hdr->ssrc        = htonl(10);    //随机指定为10，并且在本RTP会话中全局唯一  

  

        rtp_hdr->seq_no = htons(seq_num ++);  

        printf("\n\n%x\n\n",sendbuf[1]);  

        ts_current = ts_current+timestamp_increse;  

        rtp_hdr->timestamp=htonl(ts_current);  

        printf("calloc\n");  

          

          

        //free(Buf);  

        printf("read data size is %d\n",ret);  

        printf("sizeof(sendbuf) = %d",sizeof(sendbuf));  

  

        ret = send( socket1, sendbuf, ret+12, 0 );//发送rtp包  

        printf("\n\n%d\n\n",ret);  

        if(ret<0)  

        {  

            perror("send");  

            break;  

        }  

        printf("**********************************\n");  

        printf("ret = %d\n",ret);  

        printf("rtp_hdr->payload = %x\n",rtp_hdr->payload);  

        printf("rtp_hdr->version = %x\n",rtp_hdr->version);  

        printf("rtp_hdr->marker = %x\n",rtp_hdr->marker);  

        printf("rtp_hdr->ssrc = %x\n",rtp_hdr->ssrc);  

        printf("rtp_hdr->seq_no = %x\n",rtp_hdr->seq_no);  

        printf("rtp_hdr->timestamp = %x\n",rtp_hdr->timestamp);  

        printf("sendbuf[0]= %x\n",sendbuf[0]);  

        printf("sendbuf[12]= %x\n",sendbuf[12]);  

        printf("**********************************\n");  

  

        usleep(19000);  

        memset(sendbuf,0,1500); 

    }  

    fclose(file_g711);  

    printf("end !!!!!!!!!!!!!!!!!!\n");  

    return 0;  

}