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• LIVE555 RTSP H.264 Raw Video File Stream - ffplay Errors

  22 octobre 2015, par Chris.

  I am streaming a raw .h264 video file via RTSP using LIVE555.

  To receive the stream I am using ffplay. However, when watching the video I notice bad video quality and a bunch of errors in the ffplay-console :

  Input #0, rtsp, from 'rtsp://xx.xx.xxx.x/stream': sq=    0B f=0/0
  
    Metadata:
  
      title           : stream
  
      comment         : stream
  
  Duration: N/A, start: 0.099989, bitrate: N/A
  
      Stream #0:0: Video: h264 (High), yuv420p(tv, smpte170m/smpte170m/bt470m), 16
  
  80x1050 [SAR 1:1 DAR 8:5], 60 fps, 60 tbr, 90k tbn, 120 tbc
  
  [h264 @ 03f92100] RTP: missed 46 packetsq=   28KB sq=    0B f=1/1
  
  [h264 @ 03f92100] RTP: missed 74 packetsq=   23KB sq=    0B f=1/1
  
  [h264 @ 03f92100] RTP: missed 43 packets
  
  [h264 @ 03f92100] RTP: missed 35 packetsq=  179KB sq=    0B f=1/1
  
  [h264 @ 05710640] left block unavailable for requested intra4x4 mode -1 at 0 38
  
  [h264 @ 05710640] error while decoding MB 0 38, bytestream 48108
  
  [h264 @ 05710640] Cannot use next picture in error concealment
  
  [h264 @ 05710640] concealing 2989 DC, 2989 AC, 2989 MV errors in P frame
  
  [h264 @ 051043c0] left block unavailable for requested intra4x4 mode -1 at 0 26
  
  [h264 @ 051043c0] error while decoding MB 0 26, bytestream 5894
  
  [h264 @ 051043c0] concealing 4249 DC, 4249 AC, 4249 MV errors in I frame
  
  [h264 @ 03f92100] RTP: missed 68 packetsq=   28KB sq=    0B f=1/1
  
  [h264 @ 03f92100] RTP: missed 31 packetsq=  153KB sq=    0B f=1/1
  
  [h264 @ 052a0020] concealing 3292 DC, 3292 AC, 3292 MV errors in I frame
  
  [h264 @ 052a0020] Cannot use next picture in error concealment1/1
  
  [h264 @ 052a0020] concealing 2190 DC, 2190 AC, 2190 MV errors in P frame
  
  [h264 @ 03f92100] RTP: missed 69 packetsq=   27KB sq=    0B f=1/1
  
  [h264 @ 052a0020] concealing 3732 DC, 3732 AC, 3732 MV errors in I frame
  
  [h264 @ 03f92100] RTP: missed 26 packetsq=   30KB sq=    0B f=1/1
  
  ...

  How can I determine what’s wrong here ? Either with the stream or the file ?

• FFMPEG and DirectX Capture in C++

  13 décembre 2016, par tankyx

  I have a system that allows me to capture a window and save it as a mp4, using ffmpeg. I use gdigrab to capture the frame, but it is fairly slow (60ms per av_read_frame calls)

  I know I can capture a game using the DirectX API, but I don’t know how to convert the resulting BMP to an AVFrame.

  The following code is the DirectX code I use to capture the frame

  extern void* pBits;
  
  extern IDirect3DDevice9* g_pd3dDevice;
  
  IDirect3DSurface9* pSurface;
  
  g_pd3dDevice->CreateOffscreenPlainSurface(ScreenWidth, ScreenHeight,
  
                                        D3DFMT_A8R8G8B8, D3DPOOL_SCRATCH, 
  
                                        &pSurface, NULL);
  
  g_pd3dDevice->GetFrontBufferData(0, pSurface);
  
  D3DLOCKED_RECT lockedRect;
  
  pSurface->LockRect(&lockedRect,NULL,
  
                 D3DLOCK_NO_DIRTY_UPDATE|
  
                 D3DLOCK_NOSYSLOCK|D3DLOCK_READONLY)));
  
  for( int i=0 ; i < ScreenHeight ; i++)
  
  {
  
      memcpy( (BYTE*) pBits + i * ScreenWidth * BITSPERPIXEL / 8 , 
  
           (BYTE*) lockedRect.pBits + i* lockedRect.Pitch , 
  
           ScreenWidth * BITSPERPIXEL / 8);
  
  }
  
  g_pSurface->UnlockRect();
  
  pSurface->Release();

  And here is my read loop :

  {
  
      while (1) {
  
      if (av_read_frame(pFormatCtx, &packet) < 0 || exit)
  
          break;
  
      if (packet.stream_index == videoindex) {
  
          // Decode video frame
  
          av_packet_rescale_ts(&packet, { 1, std::stoi(pParser->GetVal("video-fps")) }, pCodecCtx->time_base);
  
          avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
  
  
  
          if (frameFinished) {
  
              pFrame->pts = i;
  
              i++;
  
              sws_scale(sws_ctx, (uint8_t const * const *)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
  
              pFrameRGB->pts = pFrame->pts;
  
              enc.encodeFrame(pFrameRGB);
  
  
  
      }
  
      // Free the packet that was allocated by av_read_frame
  
      av_free_packet(&packet);
  
  }

  How can I create an AVFrame using the bmp I have, without using the av_read_frame ?

• FFmpeg : Decoding AVPackets received from UDP socket

  8 août 2022, par strong_kobayashi

  I am trying to stream video frames encoded with FFmpeg from an Unity game to a client UI via UDP. To be specific, I am sending AVPackets (which contain the compressed frames, as far as I understand) from the server, which are then, on the client side, extracted as follows :

  



  inline UDPpacket* SDLGameClient::receiveData()
{
    if(SDLNet_UDP_Recv(socket, packet))
        return packet;
    else
        return NULL;
}

int main()
{
    ...
    // Initialize UDP
    ...
    UDPpacket *udpPacket;

    int i = 0;

    for(;;)
    {
        udpPacket = client->receiveData();

        if(udpPacket != nullptr)
        {
            i++;
            std::cout << "Packet " << i << " received!" << std::endl;

            AVPacket packet;
            av_init_packet(&packet);

            packet.data = new uint8_t[udpPacket->len];
            memcpy(packet.data, udpPacket->data, udpPacket->len);
            packet.size = udpPacket->len;

            ...


  



  To realize networking, I use the SDL_net library. Fragmenting, sending and receiving the packets seem to work without any problem. My question is, how do I decode the incoming AVPackets and stream the frames recorded in Unity to the client ?
I am aware that I need to use avcodec_send_packet and avcodec_receive_frame for decoding (since avcodec_decode_video2, that is used in many example decoding code, is deprecated), but when I do something like this :

  



  int ret = avcodec_send_packet(codecContext, &packet);
if(ret < 0 || ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
    std::cout << "avcodec_send_packet: " << ret << std::endl;
else
{
    while(ret >= 0)
    {
        ret = avcodec_receive_frame(codecContext, frame);
        if(ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
            std::cout << "avcodec_receive_frame: " << ret << std::endl;

        std::cout << "Frame: " << codecContext->frame_number << std::endl;
    }
}

av_packet_unref(packet);


  



  ret always returns a negative value (-22), so perhaps something is wrong with the AVPackets, or I'm sending the frames way too fast, I really have no clue :/

  



  Thanks in advance for any help !