配置好rtmpdump库后，我们可以先用命令行来推流看下效果
使用librtmp发布RTMP流的可以使用两种API：RTMP_SendPacket()和RTMP_Write()。
使用RTMP_SendPacket()发布流的时候的函数执行流程图如下图所示。
流程图中关键函数的作用如下所列：
下面将本地FLV文件发布到RTMP流媒体服务器。这个只是简单的demo。
#define uint32_t unsigned int
#define HTON16(x) ((x>>8&0xff)|(x<<8&0xff00))
#define HTON24(x) ((x>>16&0xff)|(x<<16&0xff0000)|(x&0xff00))
#define HTON32(x) ((x>>24&0xff)|(x>>8&0xff00)|\
(x<<8&0xff0000)|(x<<24&0xff000000))
#define HTONTIME(x) ((x>>16&0xff)|(x<<16&0xff0000)|(x&0xff00)|(x&0xff000000))
/*read 1 byte*/
int ReadU8(uint32_t *u8,FILE*fp){
if(fread(u8,1,1,fp)!=1)
return 0;
return 1;
}
/*read 2 byte*/
int ReadU16(uint32_t *u16,FILE*fp){
if(fread(u16,2,1,fp)!=1)
return 0;
*u16=HTON16(*u16);
return 1;
}
/*read 3 byte*/
int ReadU24(uint32_t *u24,FILE*fp){
if(fread(u24,3,1,fp)!=1)
return 0;
*u24=HTON24(*u24);
return 1;
}
/*read 4 byte*/
int ReadU32(uint32_t *u32,FILE*fp){
if(fread(u32,4,1,fp)!=1)
return 0;
*u32=HTON32(*u32);
return 1;
}
/*read 1 byte,and loopback 1 byte at once*/
int PeekU8(uint32_t *u8,FILE*fp){
if(fread(u8,1,1,fp)!=1)
return 0;
fseek(fp,-1,SEEK_CUR);
return 1;
}
/*read 4 byte and convert to time format*/
int ReadTime(uint32_t *utime,FILE*fp){
if(fread(utime,4,1,fp)!=1)
return 0;
*utime=HTONTIME(*utime);
return 1;
}
int push_packet(char* infile,char* rtmp_server_path){
RTMP *rtmp = NULL;
RTMPPacket *packet = NULL;
uint32_t start_time = 0;
uint32_t now_time = 0;
//上一帧时间戳
long pre_frame_time = 0;
long lasttime = 0;
//下一帧是否是关键帧
int bNextIsKey = 1;
uint32_t preTagSize = 0;
uint32_t type = 0;
uint32_t datalength = 0;
uint32_t timestamp = 0;
uint32_t streamid = 0;
FILE* fp = NULL;
fp = fopen(infile,"rb");
if(!fp){
RTMP_LogPrintf("Open File Error\n");
CleanupSockets();
return -1;
}
//初始化Socket
if(!InitSockets()){
RTMP_LogPrintf("Init Socket Err\n");
return -1;
}
//为结构体“RTMP”分配内存
rtmp = RTMP_Alloc();
if(!rtmp){
RTMP_LogPrintf("RTMP_Alloc failed\n");
return -1;
}
//初始化结构体“RTMP”中的成员变量
RTMP_Init(rtmp);
rtmp->Link.timeout = 5;
if(!RTMP_SetupURL(rtmp, rtmp_server_path)){
RTMP_Log(RTMP_LOGERROR,"SetupURL Err\n");
RTMP_Free(rtmp);
CleanupSockets();
return -1;
}
//发布流的时候必须要使用。如果不使用则代表接收流。
RTMP_EnableWrite(rtmp);
//建立RTMP连接，创建一个RTMP协议规范中的NetConnection
if (!RTMP_Connect(rtmp,NULL)){
RTMP_Log(RTMP_LOGERROR,"Connect Err\n");
RTMP_Free(rtmp);
CleanupSockets();
return -1;
}
//创建一个RTMP协议规范中的NetStream
if (!RTMP_ConnectStream(rtmp,0)){
RTMP_Log(RTMP_LOGERROR,"ConnectStream Err\n");
RTMP_Close(rtmp);
RTMP_Free(rtmp);
CleanupSockets();
return -1;
}
packet=(RTMPPacket*)malloc(sizeof(RTMPPacket));
RTMPPacket_Alloc(packet,1024*64);
RTMPPacket_Reset(packet);
packet->m_hasAbsTimestamp = 0;
packet->m_nChannel = 0x04;
packet->m_nInfoField2 = rtmp->m_stream_id;
RTMP_LogPrintf("Start to send data ...\n");
//跳过flv的9个头字节
fseek(fp,9,SEEK_SET);
//跳过previousTagSize所占的4个字节
fseek(fp,4,SEEK_CUR);
start_time=RTMP_GetTime();
while(1)
{
//如果下一帧是关键帧，且上一帧的时间戳比现在的时间还长(外部时钟)，说明推流速度过快了，可以延时下
if((((now_time=RTMP_GetTime())-start_time)<(pre_frame_time)) && bNextIsKey)
{
//wait for 1 sec if the send process is too fast
//这个机制不好，需要改进
if(pre_frame_time>lasttime){
RTMP_LogPrintf("TimeStamp:%8lu ms\n",pre_frame_time);
lasttime=pre_frame_time;
}
sleep(1);//等待1秒
continue;
}
//not quite the same as FLV spec
if(!ReadU8(&type,fp))//读取type
break;
if(!ReadU24(&datalength,fp))//读取datalength的长度
break;
if(!ReadTime(×tamp,fp))//从flv的head读取时间戳
break;
if(!ReadU24(&streamid,fp))//读取streamid的类型
break;
if(type!=0x08&&type!=0x09){//如果不是音频或视频类型
//jump over non_audio and non_video frame，
//jump over next previousTagSizen at the same time
fseek(fp,datalength+4,SEEK_CUR);//跳过脚本以及脚本后的previousTagSize
continue;
}
//把flv的音频和视频数据写入到packet的body中
if(fread(packet->m_body,1,datalength,fp)!=datalength)
break;
//packet header 大尺寸
packet->m_headerType = RTMP_PACKET_SIZE_LARGE;
packet->m_nTimeStamp = timestamp;//时间戳
packet->m_packetType = type;//包类型
packet->m_nBodySize = datalength;//包大小
pre_frame_time=timestamp;//把包读取到的时间戳赋值给上一帧时间戳变量
if (!RTMP_IsConnected(rtmp)){//确认连接
RTMP_Log(RTMP_LOGERROR,"rtmp is not connect\n");
break;
}
RTMP_Log(RTMP_LOGINFO,"send packet\n");
//发送一个RTMP数据RTMPPacket
if (!RTMP_SendPacket(rtmp,packet,0)) {
RTMP_Log(RTMP_LOGERROR,"Send Error\n");
break;
}
if(!ReadU32(&preTagSize,fp))
break;
if(!PeekU8(&type,fp))//去读下一帧的类型
break;
if(type==0x09){//如果下一帧是视频
if(fseek(fp,11,SEEK_CUR)!=0)
break;
if(!PeekU8(&type,fp)){
break;
}
if(type==0x17)//如果视频帧是关键帧
bNextIsKey=1;
else
bNextIsKey=0;
fseek(fp,-11,SEEK_CUR);
}
}
RTMP_LogPrintf("\nSend Data Over!\n");
if(fp) {
fclose(fp);
}
if (rtmp!=NULL){
//关闭RTMP连接
RTMP_Close(rtmp);
//释放结构体RTMP
RTMP_Free(rtmp);
rtmp=NULL;
}
if (packet!=NULL){
RTMPPacket_Free(packet);
free(packet);
packet=NULL;
}
//关闭Socket
CleanupSockets();
return 0;
}
void showuse(){
RTMP_LogPrintf("--rtmp|-h help\n");
RTMP_LogPrintf("--rtmp|-v version\n");
RTMP_LogPrintf("--rtmp|-i url push file\n");
RTMP_LogPrintf("--rtmp|-s url URL (e.g. rtmp://host[:port]/path)\n");
}
int
main(int argc, char **argv)
{
//设置log为info级别
RTMP_debuglevel = RTMP_LOGINFO;
char* infile = "in.flv";
char* rtmpserverpath = "rtmp://localhost:1935/hls";
struct option opts[] = {
{"help", no_argument, NULL, 'h'},
{"version", no_argument, NULL, 'v'},
{"infile", no_argument, NULL, 'i'},
{"rtmpserver", no_argument, NULL, 's'}
};
extern char* optarg;
int opt = 0;
//后面带冒号的说明我们要加参数
//如 ./rtmpdump -i in.flv -s rtmp://localhost:1935/hls
//h和v没有冒号，可以后面不加参数，如 ./rtmp h
while ((opt = getopt_long(argc, argv, "i:s:hv", opts, NULL)) != -1) {
//printf("opts:%s\n",optarg);
switch (opt) {
case 'i':
infile = strdup(optarg);
printf("infile:%s\n",infile);
break;
case 's':
rtmpserverpath = strdup(optarg);
printf("rtmpserverpath:%s\n",rtmpserverpath);
break;
case 'h':
showuse();
return 0;
case 'v':
RTMP_LogPrintf("version 1.0 by hxk\n");
return 0;
default:
showuse();
return -1;
}
}
push_packet(infile,rtmpserverpath);
return 0;
}
编译完后我们可以运行一下，
./rtmpdump -i in.flv -s rtmp://localhost:1935/hls
可以看到我们在推流了。然后用ffplay来播放一下，发现成功了。