Linux下H.264码流实时RTP打包与发送

    由于项目要求在DM6467T平台上添加实时RTP打包发送模块，这才找了找有没有人分享 这方面的经验。这里需要感谢网友：yanyuan9527，他写的文章对我帮助很大，可以说让一个完全小白的人了解了RTP打包，链接在此：http://www.chinavideo.org/forum.php?mod=viewthread&tid=7575

    一、请大家阅读上面提到的文章，我这里就不详细写了，读了之后应该对RTP打包有一定了解了。不过那篇文章是在windows下实现的，我要说的是linux。首先说linux与windows下socket的几点区别：1.linux下的socket不用初始换。2.linux下定义socketfd直接是Int型，而windows下是SOCKET结构体。下图是linux和windows下socket的区别

    二、在linux系统下移植好那篇文章提供的源代码，应该就可以跑通发包了，可以用抓包工具Wireshark抓下包试试。下面上代码：

1.rtp.h

// MPEG2RTP.h
#include <stdio.h>
#include <stdlib.h>

#include <string.h>

#include <sys/socket.h>

//#include "mem.h"

//


#define PACKET_BUFFER_END            (unsigned int)0x00000000


#define MAX_RTP_PKT_LENGTH     1400

#define DEST_IP                "192.168.0.30"
#define DEST_PORT            1234

#define H264                    96

typedef int SOCKET;

typedef struct 
{
    /**//* byte 0 */
    unsigned char csrc_len:4;        /**//* expect 0 */
    unsigned char extension:1;        /**//* expect 1, see RTP_OP below */
    unsigned char padding:1;        /**//* expect 0 */
    unsigned char version:2;        /**//* expect 2 */
    /**//* byte 1 */
    unsigned char payload:7;        /**//* RTP_PAYLOAD_RTSP */
    unsigned char marker:1;        /**//* expect 1 */
    /**//* bytes 2, 3 */
    unsigned short seq_no;            
    /**//* bytes 4-7 */
    unsigned  long timestamp;        
    /**//* bytes 8-11 */
    unsigned long ssrc;            /**//* stream number is used here. */
} RTP_FIXED_HEADER;

typedef struct {
    //byte 0
	unsigned char TYPE:5;
    unsigned char NRI:2;
	unsigned char F:1;    
         
} NALU_HEADER; /**//* 1 BYTES */

typedef struct {
    //byte 0
    unsigned char TYPE:5;
	unsigned char NRI:2; 
	unsigned char F:1;    
            
             
} FU_INDICATOR; /**//* 1 BYTES */

typedef struct {
    //byte 0
    unsigned char TYPE:5;
	unsigned char R:1;
	unsigned char E:1;
	unsigned char S:1;    
} FU_HEADER; /**//* 1 BYTES */




//BOOL InitWinsock();

2. rtp.c

// NALDecoder.cpp : Defines the entry point for the console application.
//


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include "rtp.h"

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

typedef struct
{
  int startcodeprefix_len;      //! 4 for parameter sets and first slice in picture, 3 for everything else (suggested)
  unsigned len;