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• Revision c389b37bb4 : Substantial reworking of code for arf and kf groups. Substantial restructuring

  15 août 2014, par Paul Wilkins

  Changed Paths :
   Modify /vp9/encoder/vp9_firstpass.c

  
   Modify /vp9/encoder/vp9_firstpass.h

  
   Modify /vp9/encoder/vp9_ratectrl.c

  
   Modify /vp9/encoder/vp9_ratectrl.h

  
  
  Substantial reworking of code for arf and kf groups.

  Substantial restructuring of the way we estimate
  the rate of decay in prediction quality and determine
  the arf interval and amount of boost used.

  Also other changes to support moving to a lower first pass
  Q which exposes some new features and allows us to better
  distinguish genuinely static blocks from low motion or noisy
  blocks.

  Net gains now visible on all the test sets with std-hd PSNR up
  1.87%. There are still some bad outlier cases but most of these
  are low motion or slide show type content where the metrics
  are already high at any given rate. The best + case is up by
  more than 10%.

  Change-Id : I18e25170053bdf3188f493ff8062f48a74515815

• using libav instead of ffmpeg

  21 janvier 2015, par n00bie

  I want to streaming video over http, i am using ogg(theora + vorbis), now i have sender and receiver, and i can run them using command line :

  Sender :

  ffmpeg -f video4linux2 -s 320x240 -i /dev/mycam -codec:v libtheora -qscale:v 5 -f ogg http://127.0.0.1:8080 

  Receiver :

  sudo gst-launch-0.10 tcpserversrc port = 8080 ! oggdemux ! theoradec ! autovideosink

  Now, sender sends both audio and video, but receiver plays only video.

  It works perfect, but now i want not to use ffmpeg and use only libav* instead.

  Here’s my class for streaming :

  class VCORE_LIBRARY_EXPORT VVideoWriter : private boost::noncopyable
  
  {
  
  public:
  
      VVideoWriter( );
  
      ~VVideoWriter( );
  
  
  
      bool openFile( const std::string& name,
  
                     int fps, int videoBitrate, int width, int height,
  
                     int audioSampleRate, bool stereo, int audioBitrate );
  
      void close( );
  
  
  
      bool writeVideoFrame( const uint8_t* image, int64_t timestamp );
  
      bool writeAudioFrame( const int16_t* data, int64_t timestamp  );
  
  
  
      int audioFrameSize( ) const;
  
  
  
  private:
  
      AVFrame *m_videoFrame;
  
      AVFrame *m_audioFrame;
  
  
  
      AVFormatContext *m_context;
  
      AVStream *m_videoStream;
  
      AVStream *m_audioStream;
  
  
  
      int64_t m_startTime;
  
  };

  Initialization :

  bool VVideoWriter::openFile( const std::string& name,
  
                               int fps, int videoBitrate, int width, int height,
  
                               int audioSampleRate, bool stereo, int audioBitrate )
  
  {
  
           if( ! m_context )
  
           {
  
              // initalize the AV context
  
              m_context = avformat_alloc_context( );
  
              assert( m_context );
  
  
  
              // get the output format
  
              m_context->oformat = av_guess_format( "ogg", name.c_str( ), nullptr );
  
              if( m_context->oformat )
  
              {
  
                  strcpy( m_context->filename, name.c_str( ) );
  
  
  
                  auto codecID = AV_CODEC_ID_THEORA;
  
                  auto codec = avcodec_find_encoder( codecID );
  
  
  
                  if( codec )
  
                  {
  
                      m_videoStream = avformat_new_stream( m_context, codec );
  
                      assert( m_videoStream );
  
  
  
                      // initalize codec
  
                      auto codecContext = m_videoStream->codec;
  
                      bool globalHeader = m_context->oformat->flags & AVFMT_GLOBALHEADER;
  
                      if( globalHeader )
  
                          codecContext->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
                      codecContext->codec_id = codecID;
  
                      codecContext->codec_type = AVMEDIA_TYPE_VIDEO;
  
                      codecContext->width = width;
  
                      codecContext->height = height;
  
                      codecContext->time_base.den = fps;
  
                      codecContext->time_base.num = 1;
  
                      codecContext->bit_rate = videoBitrate;
  
                      codecContext->pix_fmt = PIX_FMT_YUV420P;
  
                      codecContext->flags |= CODEC_FLAG_QSCALE;
  
                      codecContext->global_quality = FF_QP2LAMBDA * 5;
  
  
  
                      int res = avcodec_open2( codecContext, codec, nullptr );
  
  
  
                      if( res >= 0 )
  
                      {
  
                          auto codecID = AV_CODEC_ID_VORBIS;
  
                          auto codec = avcodec_find_encoder( codecID );
  
  
  
                          if( codec )
  
                          {
  
                              m_audioStream = avformat_new_stream( m_context, codec );
  
                              assert( m_audioStream );
  
                              // initalize codec
  
                              auto codecContext = m_audioStream->codec;
  
  
  
                              bool globalHeader = m_context->oformat->flags & AVFMT_GLOBALHEADER;
  
                              if( globalHeader )
  
                                  codecContext->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
                              codecContext->codec_id = codecID;
  
                              codecContext->codec_type = AVMEDIA_TYPE_AUDIO;
  
                              codecContext->sample_fmt = AV_SAMPLE_FMT_FLTP;
  
                              codecContext->bit_rate = audioBitrate;
  
                              codecContext->sample_rate = audioSampleRate;
  
                              codecContext->channels = stereo ? 2 : 1;
  
                              codecContext->channel_layout = stereo ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
  
  
  
                              res = avcodec_open2( codecContext, codec, nullptr );
  
  
  
                              if( res >= 0 )
  
                              {
  
                                  // try to open the file
  
                                  if( avio_open( &m_context->pb, m_context->filename, AVIO_FLAG_WRITE ) >= 0 )
  
                                  {
  
                                      m_audioFrame->nb_samples = codecContext->frame_size;
  
                                      m_audioFrame->format = codecContext->sample_fmt;
  
                                      m_audioFrame->channel_layout = codecContext->channel_layout;
  
  
  
                                      boost::posix_time::ptime time_t_epoch( boost::gregorian::date( 1970, 1, 1 ) );
  
                                      m_context->start_time_realtime = ( boost::posix_time::microsec_clock::universal_time( ) - time_t_epoch ).total_microseconds( );
  
                                      m_startTime = -1;
  
  
  
                                      // write the header
  
                                      if( avformat_write_header( m_context, nullptr ) >= 0 )
  
                                      {
  
                                          return true;
  
                                      }
  
                                      else std::cerr << "VVideoWriter: failed to write video header" << std::endl;
  
                                  }
  
                                  else std::cerr << "VVideoWriter: failed to open video file " << name << std::endl;
  
                              }
  
                              else std::cerr << "VVideoWriter: failed to initialize audio codec" << std::endl;
  
                          }
  
                          else std::cerr << "VVideoWriter: requested audio codec is not supported" << std::endl;
  
                      }
  
                      else std::cerr << "VVideoWriter: failed to initialize video codec" << std::endl;
  
                  }
  
                  else std::cerr << "VVideoWriter: requested video codec is not supported" << std::endl;
  
              }
  
              else std::cerr << "VVideoWriter: requested video format is not supported" << std::endl;
  
  
  
              avformat_free_context( m_context );
  
              m_context = nullptr;
  
              m_videoStream = nullptr;
  
              m_audioStream = nullptr;
  
          }
  
          return false;
  
  }

  Writing video :

  bool VVideoWriter::writeVideoFrame( const uint8_t* image, int64_t timestamp )
  
  {
  
      if( m_context ) {
  
          auto codecContext = m_videoStream->codec;
  
          avpicture_fill( reinterpret_cast( m_videoFrame ),
  
                          const_cast( image ),
  
                          codecContext->pix_fmt, codecContext->width, codecContext->height );
  
  
  
          AVPacket pkt;
  
          av_init_packet( & pkt );
  
          pkt.data = nullptr;
  
          pkt.size = 0;
  
          int gotPacket = 0;
  
          if( ! avcodec_encode_video2( codecContext, &pkt, m_videoFrame, & gotPacket ) ) {
  
              if( gotPacket == 1 ) {
  
                  pkt.stream_index = m_videoStream->index;
  
                  int res;
  
                  {
  
                      pkt.pts = AV_NOPTS_VALUE;
  
                      pkt.dts = AV_NOPTS_VALUE;
  
                      pkt.stream_index = m_videoStream->index;
  
                      res = av_write_frame( m_context, &pkt );
  
                  }
  
                  av_free_packet( & pkt );
  
                  return res >= 0;
  
              }
  
              assert( ! pkt.size );
  
              return true;
  
          }
  
      }
  
      return false;
  
  }

  Writing audio (now i write test dummy audio) :

  bool VVideoWriter::writeAudioFrame( const int16_t* data, int64_t timestamp )
  
  {
  
      if( m_context ) {
  
          auto codecContext = m_audioStream->codec;
  
  
  
          int buffer_size = av_samples_get_buffer_size(nullptr, codecContext->channels, codecContext->frame_size, codecContext->sample_fmt, 0);
  
  
  
          float *samples = (float*)av_malloc(buffer_size);
  
  
  
          for (int i = 0; i < buffer_size / sizeof(float); i++)
  
              samples[i] = 1000. * sin((double)i/2.);
  
  
  
          int ret = avcodec_fill_audio_frame( m_audioFrame, codecContext->channels, codecContext->sample_fmt, (const uint8_t*)samples, buffer_size, 0);
  
  
  
          assert( ret >= 0 );
  
          (void)(ret);
  
  
  
          AVPacket pkt;
  
          av_init_packet( & pkt );
  
          pkt.data = nullptr;
  
          pkt.size = 0;
  
          int gotPacket = 0;
  
          if( ! avcodec_encode_audio2( codecContext, &pkt, m_audioFrame, & gotPacket ) ) {
  
              if( gotPacket == 1 ) {
  
                  pkt.stream_index = m_audioStream->index;
  
                  int res;
  
                  {
  
                      pkt.pts = AV_NOPTS_VALUE;
  
                      pkt.dts = AV_NOPTS_VALUE;
  
                      pkt.stream_index = m_audioStream->index;
  
                      res = av_write_frame( m_context, &pkt );
  
                  }
  
                  av_free_packet( & pkt );
  
                  return res >= 0;
  
              }
  
              assert( ! pkt.size );
  
              return true;
  
          }
  
          return false;
  
      }
  
      return false;
  
  }

  Here’s test example (i send video from webcam and dummy audio) :

  class TestVVideoWriter : public sigslot::has_slots<>
  
  {
  
  public:
  
      TestVVideoWriter( ) :
  
          m_fileOpened( false )
  
      {
  
      }
  
  
  
      void onCapturedFrame( cricket::VideoCapturer*, const cricket::CapturedFrame* capturedFrame )
  
      {
  
          if( m_fileOpened ) {
  
              m_writer.writeVideoFrame( reinterpret_cast<const>( capturedFrame->data ),
  
                                        capturedFrame->time_stamp / 1000 );
  
              m_writer.writeAudioFrame( nullptr , 0 );
  
  
  
  
  
          } else {
  
                m_fileOpened = m_writer.openFile( "http://127.0.0.1:8080",
  
                                                  15, 40000, capturedFrame->width, capturedFrame->height,
  
                                                  16000, false, 64000 );
  
          }
  
      }
  
  
  
  public:
  
      vcore::VVideoWriter m_writer;
  
      bool m_fileOpened;
  
  };
  
  
  
  TestVVideoWriter testWriter;
  
  
  
  BOOST_AUTO_TEST_SUITE(TEST_VIDEO_WRITER)
  
  
  
  BOOST_AUTO_TEST_CASE(testWritingVideo)
  
  {
  
      cricket::LinuxDeviceManager deviceManager;
  
      std::vector devs;
  
      if( deviceManager.GetVideoCaptureDevices( &amp;devs ) ) {
  
          if( devs.size( ) ) {
  
              boost::shared_ptr camera( deviceManager.CreateVideoCapturer( devs[ 0 ] ) );
  
              if( camera ) {
  
                  cricket::VideoFormat format( 320, 240, cricket::VideoFormat::FpsToInterval( 30 ),
  
                                               camera->GetSupportedFormats( )->front( ).fourcc );
  
                  cricket::VideoFormat best;
  
                  if( camera->GetBestCaptureFormat( format, &amp;best ) ) {
  
                      camera->SignalFrameCaptured.connect( &amp;testWriter, &amp;TestVVideoWriter::onCapturedFrame );
  
                      if( camera->Start( best ) != cricket::CS_FAILED ) {
  
                          boost::this_thread::sleep( boost::posix_time::seconds( 10 ) );
  
                          return;
  
                      }
  
                  }
  
              }
  
          }
  
      }
  
      std::cerr &lt;&lt; "Problem has occured with camera" &lt;&lt; std::endl;
  
  }
  
  
  
  BOOST_AUTO_TEST_SUITE_END() // TEST_VIDEO_WRITER 
  
  </const>

  But, in this case, gstreamer start playing video only when my test program stop executing (after 10 seconds in this case). It does not suit me, i want gstreamer start playing immediately after starting my test program.

  Could someone help me ?

  P.S. Sorry for my English.

• C++/CLI — 0xc000007b (INVALID_IMAGE_FORMAT) with /clr option on

  9 mars 2015, par OverMachoGrande

  I’m trying to build a C++/CLI executable to which I statically link ffmpeg (libavcodec, libavformat, libavutil & swscale). It works fine if I build it normally (without /clr, so no CLR support), it works. However, when I add CLR support, it won’t start up with a 0xc000007b. A "Hello World" C++/CLI app runs fine, though.

  Supposedly the same thing happens with Boost::Threads, but since ffmpeg is pure C, I doubt it’s using Boost.

  My config :

  • Visual Studio 2008 Professional SP1
  • Windows XP Pro SP3 (x86)
  • .NET Framework 3.5 SP1

  Thanks,
  Robert