PayloadAPP/Src/Video/cffmpeg_decode.cpp

#include "cffmpeg_decode.h"
Cffmpeg_decode::Cffmpeg_decode() {
  fmtCtx = avformat_alloc_context();
  pkt = av_packet_alloc();
  yuvFrame = av_frame_alloc();
  rgbFrame = av_frame_alloc();
}

Cffmpeg_decode::~Cffmpeg_decode() {
  if (!pkt)
    av_packet_free(&pkt);
  if (!yuvFrame)
    av_frame_free(&yuvFrame);
  if (!rgbFrame)
    av_frame_free(&rgbFrame);
  if (!videoCodecCtx)
    avcodec_free_context(&videoCodecCtx);
  if (!videoCodecCtx)
    avcodec_close(videoCodecCtx);
  if (!fmtCtx)
    avformat_close_input(&fmtCtx);
}

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

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

  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);
  fmtCtx->flags |= AVFMT_FLAG_NONBLOCK;
  if (avformat_open_input(&fmtCtx, _url.toUtf8().data(), NULL, &avdic) < 0) {
    printf("Cannot open input file.\n");
    return 0;
  }

  if (avformat_find_stream_info(fmtCtx, NULL) < 0) {
    printf("Cannot find any stream in file.\n");
    return 0;
  }

  int streamCnt = fmtCtx->nb_streams;
  for (int i = 0; i < streamCnt; i++) {
    if (fmtCtx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
      videoStreamIndex = i;
      continue;
    }
  }

  if (videoStreamIndex == -1) {
    printf("Cannot find video stream in file.\n");
    return 0;
  }

  AVCodecParameters *videoCodecPara =
      fmtCtx->streams[videoStreamIndex]->codecpar;

  if (!(videoCodec = avcodec_find_decoder(videoCodecPara->codec_id))) {
    printf("Cannot find valid decode codec.\n");
    return 0;
  }

  if (!(videoCodecCtx = avcodec_alloc_context3(videoCodec))) {
    printf("Cannot find valid decode codec context.\n");
    return 0;
  }

  if (avcodec_parameters_to_context(videoCodecCtx, videoCodecPara) < 0) {
    printf("Cannot initialize parameters.\n");
    return 0;
  }
  if (avcodec_open2(videoCodecCtx, videoCodec, NULL) < 0) {
    printf("Cannot open codec.\n");
    return 0;
  }
  img_ctx = sws_getContext(videoCodecCtx->width, videoCodecCtx->height,
                           videoCodecCtx->pix_fmt, videoCodecCtx->width,
                           videoCodecCtx->height, AV_PIX_FMT_RGB32, SWS_BICUBIC,
                           NULL, NULL, NULL);

  numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB32, videoCodecCtx->width,
                                      videoCodecCtx->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, videoCodecCtx->width,
                                 videoCodecCtx->height, 1);
  if (res < 0) {
    qDebug() << "Fill arrays failed.";
    return 0;
  }

  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;
  }

  while (av_read_frame(fmtCtx, pkt) >= 0) {
    if (pkt->stream_index == videoStreamIndex) {
      if (avcodec_send_packet(videoCodecCtx, pkt) >= 0) {
        int ret;
        while ((ret = avcodec_receive_frame(videoCodecCtx, yuvFrame)) >= 0) {
          if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
            return;
          else if (ret < 0) {
            fprintf(stderr, "Error during decoding\n");
            exit(1);
          }
          sws_scale(img_ctx, yuvFrame->data, yuvFrame->linesize, 0,
                    videoCodecCtx->height, rgbFrame->data, rgbFrame->linesize);

          QImage img(out_buffer, videoCodecCtx->width, videoCodecCtx->height,
                     QImage::Format_RGB32);
          emit sendQImage(img);

          // int m_timeframe= ((double)videoCodecCtx->framerate.den /
          // videoCodecCtx->framerate.num)*1000;
          QThread::msleep(28);
        }
      }
      av_packet_unref(pkt);
    }
    if (IsstopPlay) {
      break;
    }
  }

  qDebug() << "All video play done";
}

// 退出
void Cffmpeg_decode::stop() {
  IsstopPlay = true;
  if (!pkt)
    av_packet_free(&pkt);
  if (!yuvFrame)
    av_frame_free(&yuvFrame);
  if (!rgbFrame)
    av_frame_free(&rgbFrame);
  if (!videoCodecCtx)
    avcodec_free_context(&videoCodecCtx);
  if (!videoCodecCtx)
    avcodec_close(videoCodecCtx);
  if (!fmtCtx)
    avformat_close_input(&fmtCtx);
}