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• (ffmpeg.autogen)How can i Play RTSP Stream Audio With Video

  1er octobre 2018, par newbie

  I am making rtsp stream player to use opencv..

  The example Project is wonderful.

  But that is with not Sound

  I Added thid Code and I think I found Audio Stream Number, but I don’t know next step

      private readonly AVCodecContext* _aCodecContext;
  
      private readonly AVFormatContext* _aFormatContext;
  
      private readonly int _a_streamIndex;
  
  
  
      public VideoStreamDecoder(string url)
  
      {
  
          _vFormatContext = ffmpeg.avformat_alloc_context();
  
  
  
          var pFormatContext = _vFormatContext;
  
          ffmpeg.avformat_open_input(&pFormatContext, url, null, null).ThrowExceptionIfError();
  
  
  
          ffmpeg.avformat_find_stream_info(_vFormatContext, null).ThrowExceptionIfError();
  
  
  
          // find the first video stream
  
          AVStream* vStream = null;
  
          for (var i = 0; i < _vFormatContext->nb_streams; i++)
  
              if (_vFormatContext->streams[i]->codec->codec_type == AVMediaType.AVMEDIA_TYPE_VIDEO)
  
              {
  
                  vStream = _vFormatContext->streams[i];
  
                  break;
  
              }
  
  
  
          // find Audio stream
  
          AVStream* aStream = null;
  
          for (var i = 0; i < _vFormatContext->nb_streams; i++)
  
              if (_vFormatContext->streams[i]->codec->codec_type == AVMediaType.AVMEDIA_TYPE_AUDIO)
  
              {
  
                  aStream = _vFormatContext->streams[i];
  
                  break;
  
              }
  
  
  
          if (vStream == null) throw new InvalidOperationException("Could not found video stream.");
  
  
  
          _v_streamIndex = vStream->index;
  
          _vCodecContext = vStream->codec;
  
  
  
          _a_streamIndex = aStream->index;
  
          _aCodecContext = aStream->codec;
  
  
  
          var vcodecId = _vCodecContext->codec_id;
  
          var vCodec = ffmpeg.avcodec_find_decoder(vcodecId);
  
  
  
          var acodecId = _aCodecContext->codec_id;
  
          var aCodec = ffmpeg.avcodec_find_decoder(acodecId);
  
  
  
          if (vCodec == null) throw new InvalidOperationException("Unsupported codec.");
  
  
  
          ffmpeg.avcodec_open2(_vCodecContext, vCodec, null).ThrowExceptionIfError();
  
          ffmpeg.avcodec_open2(_aCodecContext, aCodec, null).ThrowExceptionIfError();
  
  
  
          vCodecName = ffmpeg.avcodec_get_name(vcodecId);
  
          aCodecName = ffmpeg.avcodec_get_name(acodecId);
  
          FrameSize = new Size(_vCodecContext->width, _vCodecContext->height);
  
          PixelFormat = _vCodecContext->pix_fmt;
  
  
  
          _pPacket = ffmpeg.av_packet_alloc();
  
          _pFrame = ffmpeg.av_frame_alloc();
  
      } 

• How do I properly enable ffmpeg for matplotlib.animation ?

  9 novembre 2018, par spanishgum

  I have covered a lot of ground on stack so far trying to get ffmpeg going so I can make a timelapse video.

  I am on a CentOS 7 machine, running python3.7.0a0.

  python3
  
  >>> import numpy as np
  
  >>> np.__version__
  
  '1.12.0'
  
  >>> import matplotlib as mpl
  
  >>> mpl.__version__
  
  '2.0.0'
  
  >>> import mpl_toolkits.basemap as base
  
  >>> base.__version__
  
  '1.0.7'

  I found this github gist on installing ffmpeg. I used the chromium source, and installed without a prefix option (using the default).

  I have confirmed that ffmpeg is installed, although I don’t know anything about testing whether it works.

  which ffmpeg
  
  /usr/local/bin/ffmpeg
  
  
  
  ffmpeg -version
  
  ffmpeg version N-83533-gada281d Copyright (c) 2000-2017 the FFmpeg dev elopers
  
  built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-11
  
  configuration:
  
  libavutil      55. 47.100 / 55. 47.100
  
  libavcodec     57. 80.100 / 57. 80.100
  
  libavformat    57. 66.102 / 57. 66.102
  
  libavdevice    57.  2.100 / 57.  2.100
  
  libavfilter     6. 73.100 /  6. 73.100
  
  libswscale      4.  3.101 /  4.  3.101
  
  libswresample   2.  4.100 /  2.  4.100

  I tried to run a few sample examples I found online :

  [1] http://matplotlib.org/examples/animation/basic_example_writer.html

  [2] https://stackoverflow.com/a/23098090/3454650

  Everything works fine up until I try to save the animation file.

  [1]

   anim.save('basic_animation.mp4', writer = FFwriter, fps=30, extra_args=['-vcodec', 'libx264'])

  [2]

  im_ani.save('im.mp4', writer=writer)

  I found here that explictly setting the path to ffmpeg might be necessary so I added this to the top of the test scripts :

  plt.rcParams['animation.ffmpeg_path'] = '/usr/local/bin/ffmpeg'

  I tried a few more tweaks in the code but always get the same response, which I do not know how to begin deciphering :

  Traceback (most recent call last):
  
    File "testanim.py", line 27, in <module>
  
      writer.grab_frame()
  
    File "/usr/local/lib/python3.7/contextlib.py", line 100, in __exit__
  
      self.gen.throw(type, value, traceback)
  
    File "/usr/local/lib/python3.7/site-packages/matplotlib/animation.py", line 256, in saving
  
      self.finish()
  
    File "/usr/local/lib/python3.7/site-packages/matplotlib/animation.py", line 276, in finish
  
      self.cleanup()
  
    File "/usr/local/lib/python3.7/site-packages/matplotlib/animation.py", line 311, in cleanup
  
      out, err = self._proc.communicate()
  
    File "/usr/local/lib/python3.7/subprocess.py", line 836, in communicate
  
      stdout, stderr = self._communicate(input, endtime, timeout)
  
    File "/usr/local/lib/python3.7/subprocess.py", line 1474, in _communicate
  
      selector.register(self.stdout, selectors.EVENT_READ)
  
    File "/usr/local/lib/python3.7/selectors.py", line 351, in register
  
      key = super().register(fileobj, events, data)
  
    File "/usr/local/lib/python3.7/selectors.py", line 237, in register
  
      key = SelectorKey(fileobj, self._fileobj_lookup(fileobj), events, data)
  
    File "/usr/local/lib/python3.7/selectors.py", line 224, in _fileobj_lookup
  
      return _fileobj_to_fd(fileobj)
  
    File "/usr/local/lib/python3.7/selectors.py", line 39, in _fileobj_to_fd
  
      "{!r}".format(fileobj)) from None
  
  ValueError: Invalid file object: &lt;_io.BufferedReader name=6>
  
  </module>

  Is there something with my configuration that is malformed ? I searched google for this error for some time but never found anything relevant to animations / ffmpeg. Any help would be greatly appreciated.

  ---

  UPDATE :

  @LordNeckBeard pointed me here : https://trac.ffmpeg.org/wiki/CompilationGuide/Centos

  I ran into problems with installing the x264 encoding dependency. Some files in libavcodec/*.c (in the make output) were reporting undefined references to several functions. After a wild goose chase found this : https://mailman.videolan.org/pipermail/x264-devel/2015-February/010971.html

  To fix the x264 installation, I simply added some configure flags :

  ./configure --enable-static --enable-shared --extra-ldflags="-lswresample -llzma"

  ---

  UPDATE :

  So everything installed fine after fixing the libx264 problems. I went ahead and copied the ffmpeg binary from the ffmpeg_build folder into /usr/local/bin/ffmpeg.

  After running the script I was getting problems where ffmpeg could not find the libx264 shared object. I think I will have to recompile everything using different prefixes. My intuition tells me there are old files laying around after I have messed with everything, using some configuration that is broken.

  So I decided maybe I should just try to use NUX : http://linoxide.com/linux-how-to/install-ffmpeg-centos-7/
  I installed ffmpeg using the new rpm, but to no avail. I still was not able to run ffmpeg because of a missing shared object.

  Finally, instead of usiong files copied into my /usr/local/bin folder, I ran ffmpeg directly from the build bin directory. Turns out that this does work properly !

  So in essence, if I want to install ffmpeg system wide, I need to manually compile from sources again but using a nonlocal prefix.

• Video encoded by ffmpeg.exe giving me a garbage video in c# .net

  10 septembre 2018, par Amit Yadav

  I want to record video through webcam and file to be saved in .mp4 format. So for recording i am using AforgeNet.dll for recording and for mp4 format i am encoding raw video into mp4 using ffmpeg.exe using NamedPipeStreamServer as i receive frame i push into the named pipe buffer. this process works fine i have checked in ProcessTheErrorData event but when i stop recording the output file play garbage video shown in the image below

  

  Here is Code for this

     Process Process;
  
    NamedPipeServerStream _ffmpegIn;
  
      byte[]  _videoBuffer ;
  
      const string PipePrefix = @"\\.\pipe\";
  
      public void ffmpegWriter()
  
      {
  
          if(File.Exists("outputencoded.mp4"))
  
          {
  
              File.Delete("outputencoded.mp4");
  
          }
  
  
  
          _videoBuffer = new byte[widht * heigth * 4];
  
          var audioPipeName = GetPipeName();
  
          var videoPipeName = GetPipeName();
  
          var videoInArgs = $@" -thread_queue_size 512 -use_wallclock_as_timestamps 1 -f rawvideo -pix_fmt rgb32 -video_size 640x480 -i \\.\pipe\{videoPipeName}";
  
          var videoOutArgs = $"-vcodec libx264 -crf 15 -pix_fmt yuv420p -preset ultrafast -r 10";
  
          _ffmpegIn = new NamedPipeServerStream(videoPipeName, PipeDirection.Out, 1, PipeTransmissionMode.Byte, PipeOptions.Asynchronous, 0, _videoBuffer.Length);
  
          Process=StartFFmpeg($"{videoInArgs} {videoOutArgs} \"{"outputencoded.mp4"}\"", "outputencoded.mp4");
  
      }
  
  
  
   bool WaitForConnection(NamedPipeServerStream ServerStream, int Timeout)
  
      {
  
          var asyncResult = ServerStream.BeginWaitForConnection(Ar => { }, null);
  
  
  
          if (asyncResult.AsyncWaitHandle.WaitOne(Timeout))
  
          {
  
              ServerStream.EndWaitForConnection(asyncResult);
  
  
  
              return ServerStream.IsConnected;
  
          }
  
  
  
          return false;
  
      }
  
    static string GetPipeName() => $"record-{Guid.NewGuid()}";
  
  
  
   public static Process StartFFmpeg(string Arguments, string OutputFileName)
  
          {
  
              var process = new Process
  
              {
  
                  StartInfo =
  
                  {
  
                      FileName = "ffmpeg.exe",
  
                      Arguments = Arguments,
  
                      UseShellExecute = false,
  
                      CreateNoWindow = true,
  
                      RedirectStandardError = true,
  
                      RedirectStandardInput = true,
  
  
  
                  },
  
                  EnableRaisingEvents = true
  
              };
  
  
  
              //  var logItem = ServiceProvider.Get<ffmpeglog>().CreateNew(Path.GetFileName(OutputFileName));
  
  
  
              process.ErrorDataReceived += (s, e) => ProcessTheErrorData(s,e);
  
  
  
              process.Start();
  
  
  
              process.BeginErrorReadLine();
  
  
  
              return process;
  
          }
  
  </ffmpeglog>

  and Writing each frame like this.

   private void video_NewFrame(object sender, NewFrameEventArgs eventArgs)
  
          {
  
  
  
              try
  
              {
  
                  if (_recording)
  
                  {
  
  
  
                      using (var bitmap = (Bitmap) eventArgs.Frame.Clone())
  
                      {
  
                         var _videoBuffers = ImageToByte(bitmap);
  
  
  
  
  
                              if (_firstFrameTime != null)
  
                              {
  
                              bitmap.Save("image/" + DateTime.Now.ToString("ddMMyyyyHHmmssfftt")+".bmp");
  
  
  
                                  _lastFrameTask?.Wait();
  
  
  
  
  
                                  _lastFrameTask = _ffmpegIn.WriteAsync(_videoBuffers, 0, _videoBuffers.Length);
  
                              }
  
                              else
  
                              {
  
                                  if (_firstFrame)
  
                                  {
  
                                      if (!WaitForConnection(_ffmpegIn, 5000))
  
                                      {
  
                                          throw new Exception("Cannot connect Video pipe to FFmpeg");
  
                                      }
  
  
  
                                      _firstFrame = false;
  
                                  }
  
  
  
                                  _firstFrameTime = DateTime.Now;
  
                                  _lastFrameTask?.Wait();
  
  
  
                                  _lastFrameTask = _ffmpegIn.WriteAsync(_videoBuffers, 0, _videoBuffers.Length);
  
  
  
                              }
  
  
  
                      }
  
                  }
  
                  using (var bitmap = (Bitmap) eventArgs.Frame.Clone())
  
                  {
  
                      var bi = bitmap.ToBitmapImage();
  
                      bi.Freeze();
  
                      Dispatcher.CurrentDispatcher.Invoke(() => Image = bi);
  
                  }
  
              }
  
              catch (Exception exc)
  
              {
  
                  MessageBox.Show("Error on _videoSource_NewFrame:\n" + exc.Message, "Error", MessageBoxButton.OK,
  
                      MessageBoxImage.Error);
  
                  StopCamera();
  
              }
  
          }

  Even i have written each frame to disk as bitmap .bmp and frames are correct but i don’t know what’s i am missing here ? please help thanks in advance.