Recherche avancée

Sur d’autres sites (8955)

• FFmpeg output video file much smaller than uncompressed input audio file, using option to preserve original audio quality

  17 mars 2021, par Jan

  I attempt to create a video slideshow from a number of image files and an audio file in 2 steps :

  


  

  1. Create a temporary video file from a sequence of image files

  


  2. Add an audio file to the temporary video file with a delay of 5 seconds

  


  


  The audio file is an uncompressed stereo wav file, encoded with a sample rate of 44100 Hz and a bit depth of 32 bits, with a size of 40.1 MB. To preserve the lossless quality of the input audio file I use the option -c:a aac -b:a 192k as per Slideshow Wiki. However, the final output video file has a size of only 4.49 MB.

  


  How can the output video file be about 10 times smaller than the input audio file and still preserve the original lossless quality ?

  


  My code :

  


  ffmpeg -f concat -i slide-sequence.txt -c:v libx264 -r 30 -filter_complex format=yuv420p temp.mp4
ffmpeg -i temp.mp4 -i audio.wav -af "adelay=5000|5000" -c:v copy -c:a aac -b:a 192k out.mp4


  


• Continuous remultiplexing of two MPEG-TS multicasts into a single MPEG-TS multicast in the face of upstream errors

  29 mars 2021, par Anonymous Coward

  I remultiplex PIDs from two incoming multicasts into a single TS using something like below :

  


  ffmpeg -i udp://239.1.1.1:5000 -i udp://239.1.1.2:5000 -map 0:v -map 0:a -map 1:a -codec copy -f mpegts udp://239.1.1.3:5000


  


  This works well when the multicasts are stable, but occasionally one of the multicasts will disappear for a short period of time. In this case, the output stops and the remaining input buffer start to fill as it is not being drained, sometimes overrunning the circular buffer. When the failed input returns, the backed-up buffer is not drained, so there is an ongoing offset between the inputs.

  


  Is it possible to configure ffmpeg in such a way that the output continues, just without the missing PID ? eg so the video and first audio continue, but the second audio is not present for the period that input is missing.

  


  Thanks in advance !

  


• Anomalie #4729 (Nouveau) : problème d’affichage dans la colone date

  13 avril 2021, par Franck D

  Hello, j’ai essayer en local mais aussi chez ovh en php 8 et cela fait pareil.
  spip SPIP 3.3.0-dev GIT [master : 235be9bc] sans même un article dedans

  Installation d’un spip tout neuf vierge avec uniquement gd2 et les miniatures d’aciver et le plug simplog que j’ai eu via svp
  J’ai fait l’ajout d’un fichier mes_options après l’installation avec dedans :
  define(’_NO_CACHE’, -1) ;
  define(’_INTERDIRE_COMPACTE_HEAD_ECRIRE’, true) ;
  error_reporting(E_ALL^E_NOTICE) ;
  ini_set ("display_errors", "On") ;
  define(’SPIP_ERREUR_REPORT’,E_ALL) ;
  $GLOBALS[’taille_des_logs’] = 500 ;
  define(’_MAX_LOG’, 500000) ;
  define(’_LOG_FILELINE’,true) ;
  define(’_LOG_FILTRE_GRAVITE’,8) ;
  define(’_DEBUG_SLOW_QUERIES’, true) ;
  define(’_BOUCLE_PROFILER’, 5000) ;

  Je viens de me rendre compte qu’il y a un problème, si je clique pour un affichage à deux ans, pour un tableau (voir copie d’écran)