基于Live555实现RTSP服务器来推送H264实时码流

实现了一个单播的rtsp服务器来推送实时的h264码流，参考了官方的testProgs目录下的testOnDemandRTSPServer例程和liveMedia目录下的DeviceSource.cpp文件。我这边是把从摄像头采集出来的码流放入了一个缓冲队列，然后直接从缓冲队列里取出来。

rtsp.h：

#ifndef _RTSP_H_
#define _RTSP_H_

#include "liveMedia.hh"
#include "BasicUsageEnvironment.hh"

void create_rtsp_server(void);

class H264LiveServerMediaSession : public OnDemandServerMediaSubsession
{
public:
    static H264LiveServerMediaSession *createNew(UsageEnvironment &env, Boolean reuseFirstSource);
    void checkForAuxSDPLine1();
    void afterPlayingDummy1();

protected:
    H264LiveServerMediaSession(UsageEnvironment &env, Boolean reuseFirstSource);
    virtual ~H264LiveServerMediaSession(void);
    void setDoneFlag() { fDoneFlag = ~0; }

protected:
    virtual char const *getAuxSDPLine(RTPSink *rtpSink, FramedSource *inputSource);
    virtual FramedSource *createNewStreamSource(unsigned clientSessionId, unsigned &estBitrate);
    virtual RTPSink *createNewRTPSink(Groupsock *rtpGroupsock, unsigned char rtpPayloadTypeIfDynamic, FramedSource *inputSource);

private:
    char *fAuxSDPLine;
    char fDoneFlag;
    RTPSink *fDummyRTPSink;
};

// 创建一个自定义的实时码流数据源类
class H264VideoStreamSource : public FramedSource
{
public:
    static H264VideoStreamSource *createNew(UsageEnvironment &env);
    unsigned maxFrameSize() const;

protected:
    H264VideoStreamSource(UsageEnvironment &env);
    virtual ~H264VideoStreamSource();

private:
    virtual void doGetNextFrame();
    virtual void doStopGettingFrames();
};

#endif // _RTSP_H_

rtsp.cpp：
 

#include <iostream>
#include "rtsp.h"
#include "ringQueue.h"

extern ringQueue *rQueue;

void create_rtsp_server(void)
{
    TaskScheduler *scheduler;
    UsageEnvironment *env;
    RTSPServer *rtspServer;

    scheduler = BasicTaskScheduler::createNew();
    env = BasicUsageEnvironment::createNew(*scheduler);
    rtspServer = RTSPServer::createNew(*env, 8554);
    if (rtspServer == NULL)
    {
        *env << "Failed to create RTSP server: " << env->getResultMsg() << "\n";
        return;
    }

    ServerMediaSession *sms = ServerMediaSession::createNew(*env);
    sms->addSubsession(H264LiveServerMediaSession::createNew(*env, true));
    rtspServer->addServerMediaSession(sms);
    char *url = rtspServer->rtspURL(sms);
    *env << "Play the stream using url " << url << "\n";
    delete[] url;
    env->taskScheduler().doEventLoop(); // 进入事件循环
}

// H264LiveServerMediaSession 实现：
H264LiveServerMediaSession *H264LiveServerMediaSession::createNew(UsageEnvironment &env, Boolean reuseFirstSource)
{
    return new H264LiveServerMediaSession(env, reuseFirstSource);
}

H264LiveServerMediaSession::H264LiveServerMediaSession(UsageEnvironment &env, Boolean reuseFirstSource) : OnDemandServerMediaSubsession(env, reuseFirstSource)
{
    fAuxSDPLine = NULL;
    fDoneFlag = 0;
    fDummyRTPSink = NULL;
}

H264LiveServerMediaSession::~H264LiveServerMediaSession()
{
    delete[] fAuxSDPLine;
}

static void afterPlayingDummy(void *clientData)
{
    H264LiveServerMediaSession *subsess = (H264LiveServerMediaSession *)clientData;
    subsess->afterPlayingDummy1();
}

void H264LiveServerMediaSession::afterPlayingDummy1()
{
    envir().taskScheduler().unscheduleDelayedTask(nextTask());
    setDoneFlag();
}

static void checkForAuxSDPLine(void *clientData)
{
    H264LiveServerMediaSession *subsess = (H264LiveServerMediaSession *)clientData;
    subsess->checkForAuxSDPLine1();
}

void H264LiveServerMediaSession::checkForAuxSDPLine1()
{
    nextTask() = NULL;

    char const *dasl;
    if (fAuxSDPLine != NULL)
    {
        setDoneFlag();
    }
    else if (fDummyRTPSink != NULL && (dasl = fDummyRTPSink->auxSDPLine()) != NULL)
    {
        fAuxSDPLine = strDup(dasl);
        fDummyRTPSink = NULL;
        setDoneFlag();
    }
    else if (!fDoneFlag)
    {
        // try again after a brief delay:
        int uSecsToDelay = 100000; // 100 ms
        nextTask() = envir().taskScheduler().scheduleDelayedTask(uSecsToDelay,
                                                                 (TaskFunc *)checkForAuxSDPLine, this);
    }
}

char const *H264LiveServerMediaSession::getAuxSDPLine(RTPSink *rtpSink, FramedSource *inputSource)
{
    if (fAuxSDPLine != NULL)
    {
        return fAuxSDPLine;
    }

    if (fDummyRTPSink == NULL)
    {
        fDummyRTPSink = rtpSink;
        fDummyRTPSink->startPlaying(*inputSource, afterPlayingDummy, this);
        checkForAuxSDPLine(this);
    }
    envir().taskScheduler().doEventLoop(&fDoneFlag);

    return fAuxSDPLine;
}

FramedSource *H264LiveServerMediaSession::createNewStreamSource(unsigned clientSessionId, unsigned &estBitrate)
{
    estBitrate = 5000; // kbps, estimate

    H264VideoStreamSource *videoSource = H264VideoStreamSource::createNew(envir());
    if (videoSource == NULL)
    {
        return NULL;
    }

    return H264VideoStreamFramer::createNew(envir(), videoSource);
}

RTPSink *H264LiveServerMediaSession ::createNewRTPSink(Groupsock *rtpGroupsock,
                                                       unsigned char rtpPayloadTypeIfDynamic,
                                                       FramedSource *inputSource)
{
    // OutPacketBuffer::maxSize = 2000000;
    return H264VideoRTPSink::createNew(envir(), rtpGroupsock, rtpPayloadTypeIfDynamic);
}

// H264VideoStreamSource 实现：
H264VideoStreamSource *H264VideoStreamSource::createNew(UsageEnvironment &env)
{
    return new H264VideoStreamSource(env);
}

H264VideoStreamSource::H264VideoStreamSource(UsageEnvironment &env) : FramedSource(env)
{
}

H264VideoStreamSource::~H264VideoStreamSource()
{
}

unsigned  int H264VideoStreamSource::maxFrameSize() const
{
    return 100000; // 设置fMaxSize的值
}

void H264VideoStreamSource::doGetNextFrame()
{
    rQueue_data e;
    uint32_t timestamp = 0;
    static uint8_t buffer_data[1024 * 512] = {0};

    // 还没准备好要数据
    if (!isCurrentlyAwaitingData())
    {
        std::cout << "isCurrentlyAwaitingData" << std::endl;
        return;
    }

    // 从队列中取出数据
    e.buffer = buffer_data;
    e.len = sizeof(buffer_data);
    if(rQueue_de(rQueue, &e) == -1)
    {
        FramedSource::afterGetting(this);
        return;
    }

    if (e.len > fMaxSize)
    {
        fFrameSize = fMaxSize;
        fNumTruncatedBytes = e.len - fMaxSize;
    }
    else
    {
        fFrameSize = e.len;
    }
    gettimeofday(&fPresentationTime, NULL);
    memcpy(fTo, buffer_data, fFrameSize);
    FramedSource::afterGetting(this);
}

void H264VideoStreamSource::doStopGettingFrames()
{
    std::cout << "doStopGettingFrames" << std::endl;
}

文章来源地址https://uudwc.com/A/vmpNN