Recherche avancée

Sur d’autres sites (6860)

• libx264 encoded video lags by few seconds in comparison to audio

  18 septembre 2017, par Herdesh Verma

  Below is the code i am using for reading a .3gp file encoding it using libx264 and writing it to .mp4 container. Code is working but when i play .mp4 file then video is not in sync with audio. Video is few second slow in comparison to audio.

  // Read all packet from context
  
  while( av_read_frame( fmt_ctx , pAVPacket ) >= 0 )
  
  {
  
      int decoded = pAVPacket->size;
  
      if(pAVPacket->stream_index == video_stream_idx)
  
      {
  
          //decode packet
  
          value = avcodec_decode_video2(video_dec_ctx , pAVFrame , 
  
          &frameFinished , pAVPacket );
  
          if( value < 0)
  
          {
  
              av_free_packet(pAVPacket);
  
              return -1;
  
          }
  
  
  
          if(frameFinished)// Frame successfully decoded :)
  
          {
  
              sws_scale(swsCtx_, (const uint8_t *const *) pAVFrame->data, 
  
              pAVFrame->linesize, 0, video_dec_ctx->height, outFrame->data, 
  
              outFrame->linesize);
  
              av_init_packet(&outPacket);
  
              outPacket.data = NULL;    // packet data will be allocated by 
  
              the encoder
  
              outPacket.size = 0;
  
  
  
              outFrame->pts=z;
  
              //encode frame
  
              avcodec_encode_video2(outAVCodecContext , &outPacket ,outFrame , 
  
              &got_picture);
  
  
  
  
  
              if(got_picture)
  
              {
  
                  if(outPacket.pts != AV_NOPTS_VALUE)
  
                      outPacket.pts = av_rescale_q(outPacket.pts, video_st-
  
                      >codec->time_base, video_st->time_base);
  
                  if(outPacket.dts != AV_NOPTS_VALUE)
  
                      outPacket.dts = av_rescale_q(outPacket.dts, video_st-
  
                      >codec->time_base, video_st->time_base);
  
  
  
                  //Write encoded packet to file.
  
                  if(av_write_frame(outAVFormatContext , &outPacket) != 0)
  
                  {
  
                      av_free_packet(pAVPacket);
  
                      av_free_packet(&outPacket);
  
                      return -1;
  
                  }
  
                  z++;
  
                  av_free_packet(&outPacket);
  
              } // got_picture
  
          } // got_picture
  
      }
  
      // If packet is from audio stream
  
      else if (pAVPacket->stream_index == audio_stream_idx)
  
      {
  
         //Write to file without decoding and encoding it
  
         if(av_write_frame(outAVFormatContext , pAVPacket) != 0)
  
          {
  
          }
  
      }
  
      av_free_packet(pAVPacket);
  
      //z++;
  
  }// End of while-loop
  
  
  
  value = av_write_trailer(outAVFormatContext);
  
  if( value < 0)
  
  {
  
      return -1;
  
  }

  I am using below settings :

          outAVCodecContext->codec_id = AV_CODEC_ID_H264;// AV_CODEC_ID_MPEG4; // AV_CODEC_ID_H264 // AV_CODEC_ID_MPEG1VIDEO
  
      outAVCodecContext->bit_rate_tolerance = BIT_RATE_TOLERANT;
  
      outAVCodecContext->rc_max_rate = RC_MAX_RATE;
  
      outAVCodecContext->rc_buffer_size = RC_BUFFER_SIZE;
  
      outAVCodecContext->gop_size = GOP_SIZE;
  
      outAVCodecContext->b_frame_strategy = B_FRAME_STRATEGY;
  
      outAVCodecContext->coder_type = CODER_TYPE;
  
      outAVCodecContext->me_cmp = ME_CMP;
  
      outAVCodecContext->me_range = ME_RANGE; //16
  
      outAVCodecContext->qmin = QMIN;  //10
  
      outAVCodecContext->qmax = QMAX;  //51
  
      outAVCodecContext->scenechange_threshold = SCENECHANGE_THRESHOLD; //40
  
      outAVCodecContext->flags |= CODEC_FLAG_LOOP_FILTER;
  
      outAVCodecContext->me_method = ME_METHOD;
  
      outAVCodecContext->me_subpel_quality = ME_SUBPEL_QUALITY;
  
      outAVCodecContext->i_quant_factor = I_QUANT_FACTOR; //0.71
  
      outAVCodecContext->qcompress = QCOMPRESS;
  
      outAVCodecContext->max_qdiff = MAX_QDIFF;
  
      av_dict_set( &codec_options, "preset", "superfast", 0 );

  And values are defined as below :

  #define VAVLON_VALUES_H
  
  #define BIT_RATE_TOLERANT 0;
  
  #define RC_MAX_RATE 0;
  
  #define RC_BUFFER_SIZE 0;
  
  #define GOP_SIZE 40;
  
  #define B_FRAME_STRATEGY 0;
  
  #define CODER_TYPE 1;
  
  #define ME_CMP 1;
  
  #define ME_RANGE 16; //16
  
  #define QMIN 30;  //37
  
  #define QMAX 40;  //70
  
  #define SCENECHANGE_THRESHOLD 40; //40
  
  #define ME_METHOD ME_HEX;
  
  #define ME_SUBPEL_QUALITY 40;
  
  #define I_QUANT_FACTOR 0.71;
  
  #define QCOMPRESS 0.3;
  
  #define MAX_QDIFF 4;
  
  #define BIT_RATE 500000;
  
  #define CODEC_TYPE AVMEDIA_TYPE_VIDEO;
  
  #define PIX_FMT AV_PIX_FMT_YUV420P;
  
  #define MAX_B_FRAMES 0;
  
  #define NUM 1;
  
  #define DEN 30;

  Above code works as expected when i am encoding .mp4 file but i notice lag in video when i try to encode .3gp file.
  Can you please help in finding out what i am doing wrong ?

• Anomalie #4775 (Fermé) : warning en php 8 avant l’installation

  7 mai 2021, par Franck D

  Hello :)

  Firefox 88.0.1
  SPIP 4.0.0-alpha GIT [master : 42d36eda]

  Laragon avec :
  php 8.0.3
  Apache 2.4.46
  MySQL 8.0.23
  phpMyAdmin 5.1.0

  Juste pour dire que, si je vais sur l’url avant que spip soit installer, j’ai 3 warnings (qui sont aussi visible une fois l’installation faite) dans tous les cas, il suffit d’actualiser la page pour qu’elles disparaissent (voir copie d’écran)
  A savoir, j’ai un fichier mes options avec dedans :
  

  <span class="CodeRay"><span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_NO_CACHE</span><span class="delimiter">'</span></span>, -<span class="integer">1</span>);
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_INTERDIRE_COMPACTE_HEAD_ECRIRE</span><span class="delimiter">'</span></span>, <span class="predefined-constant">true</span>);
  <span class="predefined">error_reporting</span>(<span class="exception">E_ALL</span>^<span class="exception">E_NOTICE</span>);
  ini_set (<span class="string"><span class="delimiter">"</span><span class="content">display_errors</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">On</span><span class="delimiter">"</span></span>);
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">SPIP_ERREUR_REPORT</span><span class="delimiter">'</span></span>,<span class="exception">E_ALL</span>);
  <span class="predefined">$GLOBALS</span>[<span class="string"><span class="delimiter">'</span><span class="content">taille_des_logs</span><span class="delimiter">'</span></span>] = <span class="integer">500</span>;
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_MAX_LOG</span><span class="delimiter">'</span></span>, <span class="integer">500000</span>);
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_LOG_FILELINE</span><span class="delimiter">'</span></span>,<span class="predefined-constant">true</span>);
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_LOG_FILTRE_GRAVITE</span><span class="delimiter">'</span></span>,<span class="integer">8</span>);
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_DEBUG_SLOW_QUERIES</span><span class="delimiter">'</span></span>, <span class="predefined-constant">true</span>);
  <span class="predefined">define</span>(<span class="string"><span class="delimiter">'</span><span class="content">_BOUCLE_PROFILER</span><span class="delimiter">'</span></span>, <span class="integer">5000</span>);
  </span>
  Télécharger

• Anomalie #2472 : Compagnon : un bug dans un des boutons de fermeture

  2 janvier 2012, par marcimat -

  C’est vrai qu’on avait mis ce define pour ça effectivement. C’est relou parce qu’on va l’avoir pour d’autres cas ça. Suhosin est assez présent. De mémoire Cédric tu disais qu’on pouvait difficilement activer le define d’office parce que

  si un navigateur à une url ajax et que le cache est vidé, on (...)