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• swscale : Deprecate vector functions which are unused outside swscale

  31 mars 2016, par Michael Niedermayer

  swscale : Deprecate vector functions which are unused outside swscale
  There are no known users of these functions within debian
  
  It should be thus possible to remove these functions without recommandition of a
  
  replacement
  Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
  

  • [DH] libswscale/swscale.h
  • [DH] libswscale/utils.c
  • [DH] libswscale/version.h

• svq3 : eliminate write_back_intra_pred_mode() usage

  22 mars 2016, par Anton Khirnov

  svq3 : eliminate write_back_intra_pred_mode() usage
  This function depends on the h264 internals and is so tiny that just
  
  copying the code out is the simplest replacement.
  

  • [DBH] libavcodec/svq3.c

• Calling FFMPEG with Boost.Process

  10 février 2016, par CadentOrange

  I’m trying to call FFMPEG from my C++ process to stream video from an IP camera. The FFMPEG command I use is ffmpeg.exe -rtsp_transport tcp -i rtsp://10.0.1.21/ONVIF/MediaInput?profile=1_def_profile4 -f image2pipe -pix_fmt rgb24 -vcodec rawvideo -r 15 -. I’ve verified this command in the command prompt and it does start a video stream and dumps the frames to stdout. I’ve also written similar code in Python and it works.

  This is the code I’m using to call FFMPEG with the arguments from the previous paragraph in C++ and read the individual frames from stdout.

  bool build_ffmpeg_arguments(const std::string &uri, std::vector &args)
  
  {
  
      args.push_back("-rtsp_transport");
  
      args.push_back("tcp");
  
      args.push_back("-i");
  
      args.push_back(uri);
  
      args.push_back("-f");
  
      args.push_back("image2pipe");
  
      args.push_back("-pix_fmt");
  
      args.push_back("rgb24");
  
      args.push_back("-vcodec");
  
      args.push_back("rawvideo");
  
      args.push_back("-r");
  
      args.push_back("15");
  
      args.push_back("-");
  
  
  
      return true;
  
  }
  
  
  
  
  
  boost::process::child start_ffmpeg(const std::string &uri,
  
                                     const std::string &ffmpeg_path = "c:\\Tools\\ffmpeg.exe")
  
  {
  
      std::vector args;
  
      build_ffmpeg_arguments(uri, args);
  
  
  
      boost::process::context ctx;
  
      ctx.stdout_behavior = boost::process::capture_stream();
  
      ctx.stderr_behavior = boost::process::capture_stream();
  
  
  
      return boost::process::launch(ffmpeg_path, args, ctx);
  
  }
  
  
  
  bool read_frame(boost::process::pistream &amp;is, int frame_size, std::vector<char> &amp;frame_bytes)
  
  {
  
      char *buffer = new char[frame_size];
  
  
  
      frame_bytes.clear();
  
      is.read(buffer, frame_size);
  
      int bytes_read = is.gcount();
  
      frame_bytes.assign(buffer, buffer + bytes_read);
  
  
  
  //    std::cout &lt;&lt; "Is Bad: " &lt;&lt; is.bad() &lt;&lt; std::endl;
  
  //    std::cout &lt;&lt; "Is EOF: " &lt;&lt; is.eof() &lt;&lt; std::endl;
  
  //    std::cout &lt;&lt; "gcount: " &lt;&lt; bytes_read &lt;&lt; std::endl;
  
  
  
      delete[] buffer;
  
      if(is.bad() || is.eof() || bytes_read &lt; frame_size)
  
      {
  
          //We read in gunk, skip this time.
  
          is.clear();
  
          return false;
  
      }
  
      else
  
      {
  
          return true;
  
      }
  
  }
  
  
  
  
  
  //This is where the code is invoked.
  
  BOOST_AUTO_TEST_CASE(test_ffmpeg_stream)
  
  {
  
      std::string uri = "rtsp://10.0.1.21/ONVIF/MediaInput?profile=1_def_profile4";
  
      int width = 320;
  
      int height = 240;
  
      int bpp = 3;
  
      int bytes_expected = width * height * 3;
  
      boost::process::child c = start_ffmpeg(uri);
  
      boost::process::pistream &amp;is = c.get_stdout();
  
      boost::process::pistream &amp;err = c.get_stderr();
  
  
  
      std::vector<char> buffer;
  
      bool result = read_frame(is, bytes_expected, buffer);
  
      //BOOST_CHECK_EQUAL(true, result);
  
      std::cout &lt;&lt; "Buffer size: " &lt;&lt; buffer.size() &lt;&lt; std::endl;
  
  
  
      std::string line;
  
      while (std::getline(err, line))
  
          std::cout &lt;&lt; line &lt;&lt; std::endl;
  
  }
  
  </char></char>

  The output from stderr suggests that the parameters could be passed in wrong.

  ffmpeg version 2.8.3 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 5.2.0 (GCC)
  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
  
  isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
  
  le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
  
  enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-l
  
  ibilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enab
  
  le-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --en
  
  able-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --ena
  
  ble-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc
  
   --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enabl
  
  e-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --ena
  
  ble-decklink --enable-zlib
  
    libavutil      54. 31.100 / 54. 31.100
  
    libavcodec     56. 60.100 / 56. 60.100
  
    libavformat    56. 40.101 / 56. 40.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 40.101 /  5. 40.101
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.101 /  1.  2.101
  
    libpostproc    53.  3.100 / 53.  3.100
  
  rtsp://10.0.1.21/ONVIF/MediaInput?profile=1_def_profile4: Unknown error

  Is there a way of showing the full command line with arguments that boost::process::launch is calling ? Is there anything obvious that I’m doing wrong with boost::process ?

  Update :

  Suspecting that it could be the command line arguments being passed in wrong, I’ve created a dummy executable that prints out the command line arguments it receives. It’s a drop-in replacement for ffmpeg.exe purely so that I can see what command lines are being passed. The command line I’m getting is -rtsp_transport tcp -i rtsp://10.0.1.21/ONVIF/MediaInput?profile=1_def_profile4 -f image2pipe -pix_fmt rgb24 -vcodec rawvideo -r 15 -. Manually calling ffmpeg with that command line works as expected. Yet somehow it doesn’t work when launched via boost::process.

  ** Solution **

  It looks like I need to set the the environment field of the context. No idea why that fixes the problem, but it does.

  boost::process::context ctx;
  
  ctx.environment = boost::process::self::get_environment();
  
  ctx.stdout_behavior = boost::process::capture_stream();
  
  ctx.stderr_behavior = boost::process::capture_stream();