协议转换之rtsp转rtmp推流

本是古典何须时尚 2024-03-01 08:25 17阅读 0赞

有一个摄像头，比如海康的监控摄像头，可以通过rtsp流的方式访问其视频画面！需要将其画面转换为rtmp协议，并实现直播！

实现思路

我们的程序，称之为rtsp2rtmp，使用该程序实现拉取摄像头rtsp视频流，并将rtmp视频流转换为rtmp视频流，然后推送到直播服务器，直播服务器采用nginx+rtmp\_module的方式实现，

rtsp2rtmp，使用FFmpeg API来实现！

准备工作

*  visual studio
 *  FFmpeg sdk: 下载下载地址：
 *      https://ffmpeg.zeranoe.com/builds/
    
    具体实现步骤
 *  打开输入流上下文
 *      //av_register_all();
          avformat_network_init();
        
        
          m_strRtspUrl = rtspUrl;
          m_strRtmpUrl = rtmpUrl;
        
          m_pRtspAVFormatContext = NULL;
          m_nRet = 0;
        
          m_nVideoIndex = -1;
          m_nAudioIndex = -1;
          
          memset(errBuf, 0, 1024);
        
          // 1. 申请输出流上下文
          m_pRtmpAVFormatContext = NULL;
          avformat_alloc_output_context2(&m_pRtmpAVFormatContext, NULL, "flv", m_strRtmpUrl.c_str());
          if (!m_pRtmpAVFormatContext)
          {
            std::cout << "avformat_alloc_output_contex2 failed!" << std::endl;
            return false;
          }
          std::cout << "[" << m_strRtmpUrl.c_str() << "] avformat_alloc_output_context2 success " << std::endl;
    
        //1.打开输入流
          m_nRet = avformat_open_input(&m_pRtspAVFormatContext, m_strRtspUrl.c_str(), 0, 0);
          if (m_nRet != 0)
          {
            std::cout << "open " << m_strRtspUrl.c_str() << "error!" << std::endl;
            return m_nRet;
          }
          std::cout << "open " << m_strRtspUrl.c_str() << "success !" << std::endl;
        
          // 2.获得流信息
          m_nRet = avformat_find_stream_info(m_pRtspAVFormatContext, 0);
          if (m_nRet < 0)
          {
            std::cout << "avformat_find_stream_info failed" << std::endl;
            return m_nRet;
          }
        
          std::cout << "avformat_find_stream_info success" << std::endl;
          av_dump_format(m_pRtspAVFormatContext, 0, m_strRtspUrl.c_str(),0);
        
        
        
          for (int i = 0; i < m_pRtspAVFormatContext->nb_streams; i++)
          {
            if (m_pRtspAVFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) 
            {
              m_nVideoIndex = i;
            }
        
            if (m_pRtspAVFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) 
            { 
              m_nAudioIndex = i;
            }
          }
 *  打开输出流上下文
 *      //3. 申请输出AVStream(rtmp)
          const AVCodec* outCodec = avcodec_find_decoder(m_pRtspAVFormatContext->streams[m_nVideoIndex]->codecpar->codec_id);
          m_pRtmpAVStream = avformat_new_stream(m_pRtmpAVFormatContext, outCodec);
          if (!m_pRtmpAVStream)
          {
            std::cout << "[rtmp] Failed allocating output stream!" << std::endl;
            return m_nRet;
          }
        
          std::cout << "[rtmp] avformat_new_stream success!" << std::endl;
        
          //4. stream信息复制
          AVCodecContext* rtmpOutCodec = avcodec_alloc_context3(outCodec);
        
          m_nRet = avcodec_parameters_to_context(rtmpOutCodec, m_pRtspAVFormatContext->streams[m_nVideoIndex]->codecpar);
          if (m_nRet < 0)
          {
            std::cout << "[rtmp] avcodec_paramertes_to_context failed " << std::endl;
            return m_nRet;
          }
          std::cout << "[rtmp] avcodec_paramertes_to_context success" << std::endl;
        
          m_nRet = avcodec_parameters_from_context(m_pRtmpAVStream->codecpar, rtmpOutCodec);
          if (m_nRet < 0)
          {
            std::cout << "[rtmp] avcodec_parameters_from_context failed";
            return m_nRet;
          }
        
        
          if (!(m_pRtmpAVFormatContext->flags & AVFMT_NOFILE)) {
            m_nRet = avio_open2(&m_pRtmpAVFormatContext->pb, m_strRtmpUrl.c_str(), AVIO_FLAG_WRITE, NULL, NULL);
            if (m_nRet < 0) {
              av_strerror(m_nRet, errBuf, 1024);
              //std::cout << "avio_open2 failed: " << errBuf << std::endl;
              printf("avio_open2 failed: %s\n", errBuf);
              return m_nRet;
            }
          }
        
        
          //5. 写rtmp头信息
          m_nRet = avformat_write_header(m_pRtmpAVFormatContext, NULL);
          if (m_nRet < 0)
          {
            std::cout << "[rtmp] avformat_write_header failed" << std::endl;
        
            av_strerror(m_nRet, errBuf, 1024);
            printf("errBuf: %s\n", errBuf);
            //std::cout << err << std::endl;
            return m_nRet;
          }
        
          std::cout << "[rtmp] avformat_write_header success!" << std::endl;
 *  读取输入流
 *      m_nRet = av_read_frame(m_pRtspAVFormatContext, &pkt);
            if (m_nRet < 0)
            {
              break;
            }
 *  写入输出流
 *      rtspStream = m_pRtspAVFormatContext->streams[pkt.stream_index];
            rtmpStream = m_pRtmpAVFormatContext->streams[pkt.stream_index];
        
            pkt.pts = av_rescale_q_rnd(pkt.pts, rtspStream->time_base, rtmpStream->time_base, AVRounding(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));
            pkt.dts = av_rescale_q_rnd(pkt.dts, rtspStream->time_base, rtmpStream->time_base, AVRounding(AV_ROUND_NEAR_INF |AV_ROUND_PASS_MINMAX));
            pkt.duration = av_rescale_q(pkt.duration, rtspStream->time_base, rtmpStream->time_base);
        
            pkt.pos = -1;
            m_nRet = av_interleaved_write_frame(m_pRtmpAVFormatContext, &pkt);
            if (m_nRet < 0)
            {
              break;
            }
            av_packet_unref(&pkt);
    
    github传送门
 *      https://github.com/mlfcjob/Rtsp2Rtmp.git