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• Core : Required rule take precedence over number & digits rules

  11 janvier 2016, par Arkni

  Core : Required rule take precedence over number & digits rules
  Ref #1611
  
  Ref #1663
  
  Fixes #1514
  

• avformat/mpegts : respect program number when merging streams

  9 juillet 2019, par Marton Balint

  avformat/mpegts : respect program number when merging streams
  merge_pmt_versions was not usable if multiple programs were present because
  
  when it was searching for candidate streams it did not make sure that the PMT was
  
  of the same program. This caused the streams of all programs to get merged into
  
  a single (garbled) program.
  This patch makes sure that the program number (service ID) is also matching
  
  with the old streams when parsing the PMT making the feature useful for multi
  
  program streams.
  This change might cause issues for single program streams if the program number
  
  changes, but I think it is acceptable because the goal of the option is to make
  
  the parsing resilient to PID changes, and that is still working as expected.
  Signed-off-by : Marton Balint <cus@passwd.hu>
  

  • [DH] libavformat/mpegts.c

• Get Total number of frames and FPS faster than with OpenCV library in C++

  20 juillet 2018, par daniels_pa

  I need to check which video can be analyzed and which cannot given the total number of frames in a video and the fps of the video. I created a c++ program to do the checking. Analyzing each video is not an option since analyzing is time consuming.

  I used the OpenCV library for starters :

      cv::VideoCapture vid_to_analyze;
  
      vid_to_analyze.open( me_vid.vid_path.string() );
  
      me_vid.total_frames= static_cast<int>(vid_to_analyze.get(CV_CAP_PROP_FRAME_COUNT));
  
      me_vid.fps=vid_to_analyze.get(CV_CAP_PROP_FPS);
  
  
  
      if (!vid_to_analyze.isOpened())
  
      {
  
          std::cout &lt;&lt; "Skipping vid: "&lt;&lt; me_vid.vid_path.string()&lt;&lt;", couldn't open it" &lt;&lt; std::endl;
  
      }
  
      if (me_vid.fps != me_vid.fps || me_vid.fps &lt;= 0)
  
      {
  
          std::cout &lt;&lt; "For video " &lt;&lt; me_vid.vid_path.string() &lt;&lt; std::endl;
  
          std::cout &lt;&lt; "FPS of the video file cannot be determined, assuming 30"&lt;&lt; std::endl;
  
          me_vid.fps = 30;
  
      }
  
  
  
      vid_to_analyze.release();
  
  </int>

  However when debugging it becomes painfully slow (the program is faster running without the debugger attached but still very slow given the number of videos it needs to cover). I think that has something to do with 4 threads being created and deleted each time a video is opened (released).

  How to get total number of frames and fps in a faster manner ( without actually creating 4 threads !!) if i am not interested in actually grabbing frames from the video just the number of frames and fps.

  Is there a way to use ffmpeg library from c++, would that be faster and where to start ?

  EDIT : Valgrind seems to agree since (Ir=)91.66% of time spend in the vid_to_analyze.open phase