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• How to pass data cuvidParseVideoData

  28 avril 2022, par Serhan Erkovan

  I try to develop streaming program,I have 4k videos that 5 fps and 20 seconds, I encode frames with cuda encoder successfully, i send encoded data over rtp successfully but when i try to decode that data, i got 0 frame from cuvidParseVideoData. Should i do something before the cuvidParseVideoData for example use ffmpeg demuxer ?

  


  RecvDec.cpp

  


  Server* server = new Server(8890 + thread_no);
server->recv_packets();
totBuf* totBuf = server->getTotalBuf();
            if (totBuf->perBuf == nullptr) {
                
                std::cout << prompt << "perBuf null!" << std::endl;
                nVideoBytes = 1;
                continue;
            }

pVideo = new uint8_t[totBuf->totSize];
memcpy(pVideo, totBuf->perBuf->perBuf, totBuf->totSize);
nVideoBytes = totBuf->perBuf->size;
int nFrameReturned = 0;
nFrameReturned = dec.Decode(pVideo, nVideoBytes);




  


  NvDecoder.cpp

  


  int NvDecoder::Decode(const uint8_t *pData, int nSize, int nFlags, int64_t nTimestamp)
{
    m_nDecodedFrame = 0;
    m_nDecodedFrameReturned = 0;
    CUVIDSOURCEDATAPACKET packet = { 0 };
    packet.payload = pData;
    packet.payload_size = nSize;
    packet.flags = nFlags | CUVID_PKT_TIMESTAMP;
    packet.timestamp = nTimestamp;
    if (!pData || nSize == 0) {
        packet.flags |= CUVID_PKT_ENDOFSTREAM;
    }
    NVDEC_API_CALL(cuvidParseVideoData(m_hParser, &packet));
    m_cuvidStream = 0;

    return m_nDecodedFrame;
}



  


  Decode function always returns 0.
If i have to pass my datas from Ffmpeg demuxer, how can i pass type of uint8_t* data to demuxer ?
My data always starts with 0x00 0x00 0x00 0x01. This is start frame tag.

  


• Encoding of video returns 0, and nothing written to the output file

  14 juillet 2014, par AnilJ

  I have written a code to record the webcam feed into a file on disk. I am attempting to do this using IContainer class rather than IMediaWriter class. I am pasting the code snippet below showing important sections of the code.

  The problem I am facing is that nothing is being written to the file. Some of the observations I have made are as follows :

  1. In the Record() function, the ’while’ loop is kicked off, but the mVideoEncoder.encodeVideo(packet, frame, offset) ; method always returns zero (0). This results in no picture complete and no data is being written to the output file. Can you please provide clue as to what is missing ?
  2. I checked that the frame size is 80640, which confirms that frame has data.
  3. I see that only header and trailer is being written to the file.

  Let me know if you need any other information.

  public class WebcamRecorder {
  
  
  
      private boolean StartVideoEncoder() {
  
  
  
          boolean result = true;
  
  
  
          // Open a container
  
          mPositionInMicroseconds = 0;
  
          mOutputContainer = IContainer.make();
  
          mOutputContainer.open(mOutputFileName, IContainer.Type.WRITE, null);
  
  
  
          // Create the video stream and get its coder
  
          ICodec videoCodec = ICodec.findEncodingCodec(ICodec.ID.CODEC_ID_H264);
  
          IStream videoStream = mOutputContainer.addNewStream(videoCodec);
  
          mVideoEncoder = videoStream.getStreamCoder();
  
  
  
          // Setup the stream coder
  
          mFrameRate = IRational.make(1, 30);
  
          mVideoEncoder.setWidth(Constants.RESAMPLE_PICT_WIDTH);
  
          mVideoEncoder.setHeight(Constants.RESAMPLE_PICT_HEIGHT);
  
          mVideoEncoder.setFrameRate(mFrameRate);
  
          mVideoEncoder.setTimeBase(IRational.make(mFrameRate.getDenominator(),
  
                                    mFrameRate.getNumerator()));
  
          mVideoEncoder.setBitRate(350000);
  
          mVideoEncoder.setNumPicturesInGroupOfPictures(30);
  
          mVideoEncoder.setPixelType(IPixelFormat.Type.YUV420P);
  
          mVideoEncoder.setFlag(IStreamCoder.Flags.FLAG_QSCALE, true);
  
          mVideoEncoder.setGlobalQuality(0);
  
  
  
          // Open the encoder
  
          mVideoEncoder.open(null, null);
  
  
  
          // Write the header
  
          mOutputContainer.writeHeader();
  
  
  
          return result;
  
      }
  
  
  
      public void Record() {
  
  
  
          picture = GetNextPicture();
  
          image = Utils.videoPictureToImage(picture);
  
          // convert to the right image type
  
          BufferedImage bgrScreen = ConvertToType(image, BufferedImage.TYPE_3BYTE_BGR);
  
          IConverter converter = ConverterFactory.createConverter(bgrScreen, mVideoEncoder.getPixelType());
  
          IVideoPicture frame = converter.toPicture(bgrScreen, mPositionInMicroseconds);
  
          frame.setQuality(0);
  
  
  
          IPacket packet = IPacket.make();
  
          int offset = 0;
  
          while (offset < frame.getSize()) {
  
              int bytesEncoded = mVideoEncoder.encodeVideo(packet, frame, offset);
  
              if (bytesEncoded < 0) {
  
                  throw new RuntimeException("Unable to encode video.");
  
              }
  
              offset += bytesEncoded;
  
  
  
              if (packet.isComplete()) {
  
                  System.out.println("Packet is complete");
  
                  if (mOutputContainer.writePacket(packet) < 0) {
  
                      throw new RuntimeException(
  
                              "Could not write packet to container.");
  
                  }
  
  
  
                  // Update frame time
  
                  mPositionInMicroseconds += (mFrameRate.getDouble() * Math.pow(1000, 2));
  
                  break;
  
              }
  
          }
  
      }
  
  
  
      public void Cleanup() {
  
  
  
          if (mOutputContainer != null) {
  
              mOutputContainer.writeTrailer();
  
              mOutputContainer.close();
  
              // mOutputContainer.flushPackets();
  
          }
  
  
  
          if (mVideoEncoder != null) {
  
              mVideoEncoder.close();
  
          }
  
      }
  
  }

• FFmpeg returns empty byte when retrieving frames with python

  13 août 2020, par Ronald Saunfe

  I am trying to retrieve frames from a video frame by frame using ffmpeg which i downloaded here but i get an empty response as byte :
i need someone to outline what my problem is.I got the solution from a blog here
Here is my source code :

  


  import subprocess as sp

command=['bin\\ffmpeg.exe',
'-i','%s'%self.source,
'-f','image2pipe',
'-pix_fmt','rgb24',
'-vcodex','rawvideo','-']

self.pipe = sp.Popen(command, stdout = sp.PIPE, bufsize = 10**8)
Raw_image = self.pipe.stdout.read(420*360*3)