PayloadAPP/Src/Video/cffmpeg_decode.cpp

#include "cffmpeg_decode.h"
// Cffmpeg_decode::Cffmpeg_decode() {
Cffmpeg_decode::Cffmpeg_decode(QObject *parent) : QObject(parent) {
  inputFormatCtx = avformat_alloc_context();
  inputPacket = av_packet_alloc();
  yuvFrame = av_frame_alloc();
  rgbFrame = av_frame_alloc();
  avformat_network_init();
}

Cffmpeg_decode::~Cffmpeg_decode() {
  if (!inputPacket)
    av_packet_free(&inputPacket);
  if (!yuvFrame)
    av_frame_free(&yuvFrame);
  if (!rgbFrame)
    av_frame_free(&rgbFrame);
  if (!encoderCtx)
    avcodec_free_context(&encoderCtx);
  if (!encoderCtx)
    avcodec_close(encoderCtx);
  if (!decoderCtx)
    avcodec_free_context(&decoderCtx);
  if (!decoderCtx)
    avcodec_close(decoderCtx);
  if (!inputFormatCtx)
    avformat_close_input(&inputFormatCtx);
}

void Cffmpeg_decode::setUrl(QString url) { _url = url; }

bool Cffmpeg_decode::open_input_file() {
  if (_url.isEmpty())
    return 0;

  //========================解码============================
  AVDictionary *avdic = NULL;
  // 设置缓存大小，1080p可将值调大
  av_dict_set(&avdic, "buffer_size", "2048000", 0);
  // 以udp方式打开，如果以tcp方式打开将udp替换为tcp
  av_dict_set(&avdic, "rtsp_transport", "tcp", 0);
  // 设置超时断开连接时间，单位微秒//listen_timeout
  // av_dict_set(&avdic, "listen_timeout", "200000", 0);
  av_dict_set(&avdic, "stimeout", "200000", 0);
  av_dict_set(&avdic, "max_delay", "3", 0); // 设置最大时延
  av_dict_set(&avdic, "tune", "zerolatency", 0);
  av_dict_set(&avdic, "preset", "ultrafast", 0);

  inputFormatCtx->flags |= AVFMT_FLAG_NONBLOCK;

  // 打开输入流
  if (avformat_open_input(&inputFormatCtx, _url.toUtf8().data(), NULL, &avdic) <
      0) {
    printf("Cannot open input file.\n");
    return 0;
  }
  // 查找流信息
  if (avformat_find_stream_info(inputFormatCtx, NULL) < 0) {
    printf("Cannot find any stream in file.\n");
    return 0;
  }
  // 从输入流中找到第一个视频流
  for (int i = 0; i < inputFormatCtx->nb_streams; i++) {
    if (inputFormatCtx->streams[i]->codecpar->codec_type ==
        AVMEDIA_TYPE_VIDEO) {
      videoStreamIndex = i;
      continue;
    }
  }
  if (videoStreamIndex == -1) {
    printf("Cannot find video stream in file.\n");
    return 0;
  }

  // 获取视频流的解码器参数
  videoCodecPara = inputFormatCtx->streams[videoStreamIndex]->codecpar;

  decoder = avcodec_find_decoder(videoCodecPara->codec_id);
  if (!decoder) {
    printf("Cannot find valid decode codec.\n");
    return 0;
  }
  // 为解码器上下文分配空间
  decoderCtx = avcodec_alloc_context3(decoder);
  if (!decoderCtx) {
    printf("Cannot find valid decode codec context.\n");
    return 0;
  }
  // 初始化解码器上下文
  if (avcodec_parameters_to_context(decoderCtx, videoCodecPara) < 0) {
    printf("Cannot initialize parameters.\n");
    return 0;
  }
  // 打开解码器
  if (avcodec_open2(decoderCtx, decoder, NULL) < 0) {
    printf("Cannot open codec.\n");
    return 0;
  }

  // 初始化图像转换器
  swsCtx = sws_getContext(decoderCtx->width,   //
                          decoderCtx->height,  //
                          decoderCtx->pix_fmt, //
                          decoderCtx->width,   //
                          decoderCtx->height,  //
                          AV_PIX_FMT_RGB32,    //
                          SWS_BICUBIC, NULL, NULL, NULL);
  numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB32,   //
                                      decoderCtx->width,  //
                                      decoderCtx->height, //
                                      1);

  out_buffer = (unsigned char *)av_malloc(numBytes * sizeof(unsigned char));

  int res = av_image_fill_arrays(rgbFrame->data,     //
                                 rgbFrame->linesize, //
                                 out_buffer,         //
                                 AV_PIX_FMT_RGB32,   //
                                 decoderCtx->width,  //
                                 decoderCtx->height, 1);
  if (res < 0) {
    qDebug() << "Fill arrays failed.\n";
    return 0;
  }

  // 推流初始化
  if (bPushStreamFlag) {
    emit sendInitPushStream_Signal(inputFormatCtx);
  }

  // 裸流保存
  if (!openSave()) {
    return false;
  };
  return true;
}

// 线程里持续执行
void Cffmpeg_decode::run() {
  if (!open_input_file()) {
    qDebug() << "Please open video file first.";
    emit sendConnectFail(1);
    IsstopPlay = true;
    return;
  }
  if (bRecordTime) {
    startTime = av_gettime();
    qDebug() << "*******StartTime:" << QString::number(startTime);
    bRecordTime = false;
  }
  // 读取数据包
  while (av_read_frame(inputFormatCtx, inputPacket) >= 0) {
    if (IsstopPlay) {
      qDebug() << "video play stop";
      break;
    }

    if (inputPacket->stream_index == videoStreamIndex) {
      // 推流
      if (bPushStreamFlag) {
        // av_packet_clone(inputPacket);
        AVPacket *outputPacket = av_packet_clone(inputPacket);
        emit sendStreamData_Signal(outputPacket, frm_cnt);
      }

      // 保存裸流
      if (m_formatContextSave) {
        // 由于保存的m_formatContextSave只创建了一个视频流，而读取到的图像的流索引不一定为0，可能会出现错误【Invalid
        // packet stream index: 1】
        // 所以这里需要将stream_index指定为和m_formatContextSave中视频流索引相同，因为就一个流，所以直接设置为0
        inputPacket->stream_index = 0;
        av_write_frame(m_formatContextSave,
                       inputPacket); // 将数据包写入输出媒体文件
      }

      // 解码数据包
      if (avcodec_send_packet(decoderCtx, inputPacket) >= 0) {
        int ret;
        while ((ret = avcodec_receive_frame(decoderCtx, yuvFrame)) >= 0) {
          if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
            return;
          } else if (ret < 0) {
            fprintf(stderr, "Error during decoding\n");
            exit(1);
          }
          sws_scale(swsCtx,             //
                    yuvFrame->data,     //
                    yuvFrame->linesize, //
                    0,                  //
                    decoderCtx->height, //
                    rgbFrame->data,     //
                    rgbFrame->linesize);

          QImage img(out_buffer,         //
                     decoderCtx->width,  //
                     decoderCtx->height, //
                     QImage::Format_RGB32);
          emit sendQImage(img);
          QThread::msleep(28);
        }
      }
      av_packet_unref(inputPacket);
      frm_cnt++;
    }
    if (IsstopPlay) {
      if (m_formatContextSave) {
        saveDone();
      }
      break;
    }
    // 花屏
    //  if (av_read_frame(inputFormatCtx, inputPacket) < 0) {
    //    break; // 达到文件末尾
    //  }
  }
  if (m_formatContextSave) {
    saveDone();
  }
  qDebug() << "All video play done";
}

// 退出
void Cffmpeg_decode::stop() {

  // 写入输出文件的尾信息
  // av_write_trailer(outputFormatCtx);
  IsstopPlay = true;
  if (!inputPacket)
    av_packet_free(&inputPacket);
  if (!yuvFrame)
    av_frame_free(&yuvFrame);
  if (!rgbFrame)
    av_frame_free(&rgbFrame);
  if (!encoderCtx)
    avcodec_free_context(&encoderCtx);
  if (!encoderCtx)
    avcodec_close(encoderCtx);
  if (!decoderCtx)
    avcodec_free_context(&decoderCtx);
  if (!decoderCtx)
    avcodec_close(decoderCtx);
  if (!inputFormatCtx)
    avformat_close_input(&inputFormatCtx);
}

void Cffmpeg_decode::setSaveFileDirPath(QString fileDirPath) {
  saveFileDirPath = fileDirPath;
}

bool Cffmpeg_decode::openSave() {
  QDir dir;
  if (!dir.exists(saveFileDirPath)) {
    dir.mkdir(saveFileDirPath);
  }
  QString strName =
      QString("/%1.h264")
          .arg(QDateTime::currentDateTime().toString("yyyy-MM-dd HH-mm-ss"));
  strName = saveFileDirPath + strName;
  // const AVOutputFormat *ofmt = av_guess_format("mp4", NULL, NULL);
  int ret = avformat_alloc_output_context2(
      &m_formatContextSave, nullptr, nullptr, strName.toStdString().data());
  if (ret < 0) {
    // free();
    qWarning() << "DecodeVideo Error";
    return false;
  }
  // m_videoStreamOut->codecpar->codec_tag = 0;
  // if (m_formatContextSave->oformat->flags & AVFMT_GLOBALHEADER) {
  //   m_formatContextSave->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
  //   // m_videoStreamOut->codecpar->extradata = (uint8_t *)av_malloc(1024);
  //   // m_videoStreamOut->codecpar->extradata_size = 0;
  // }
  // 创建并初始化AVIOContext以访问url所指示的资源。
  ret = avio_open(&m_formatContextSave->pb, strName.toStdString().data(),
                  AVIO_FLAG_WRITE);
  if (ret < 0) {
    // free();
    qWarning() << "DecodeVideo Error";
    return false;
  }
  // 向媒体文件添加新流
  m_videoStreamOut = avformat_new_stream(m_formatContextSave, nullptr);
  if (!m_videoStreamOut) {
    qWarning() << "DecodeVideo Error";
    return false;
  }
  // 拷贝一些参数，给codecpar赋值(这里使用编码器上下文进行赋值)
  ret = avcodec_parameters_from_context(m_videoStreamOut->codecpar, decoderCtx);
  if (ret < 0) {
    // free();
    qWarning() << "avcodec_parameters_from_context Failed";
    return false;
  }

  // 写入文件头
  ret = avformat_write_header(m_formatContextSave, nullptr);
  if (ret < 0) {
    // free();
    qWarning() << "DecodeVideo Error";
    return false;
  }

  m_writeHeader = true;
  qDebug() << "开始录制视频！";
  return true;
}

void Cffmpeg_decode::saveDone() {
  if (m_formatContextSave && m_writeHeader) {
    av_write_trailer(m_formatContextSave); // 写入文件尾
    m_writeHeader = false;
  }
  // 关闭文件
  if (m_formatContextSave && !(m_formatContextSave->flags & AVFMT_NOFILE)) {
    avio_close(m_formatContextSave->pb);
    // av_freep(m_videoStreamOut);
    if (m_formatContextSave) {
      avformat_free_context(m_formatContextSave);
      m_formatContextSave = nullptr;
    }
    //  m_videoStreamOut = nullptr;
  }
}