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• Add watermark to all videos in a folder and enable it only during certain time intervals

  20 octobre 2016, par Neo Herakles

  I’m making a batch file to watermark all my videos in a folder using FFMPEG, I have to place the watermark at 1/3 of the duration of the video, I currently have this, it worked individually but I can’t seem to make it work for the whole folder, what am I doing wrong ? Also, is there a way to enable the watermark multiple times ? once at 1/3 of the duration, another at 2/3 of the duration.

  @echo off
  
  setlocal
  
  for %%I in ("%~dp0\water\*.mp4") do (
  
     for /F "delims=" %%I in ('ffprobe.exe -v error -show_entries format^=duration -of default^=noprint_wrappers^=1:nokey^=1 %%I.mp4 2^>^&1') do set "duration=%%I"
  
     'ffmpeg.exe -i "%%I" -i Watermark.png -filter_complex "[0:v]scale=iw:ih[v0];[1:v][v0]scale2ref=iw/6:ih/10[logo][0v];[0v][logo]overlay=W-w-3:H-h-3:enable='between(t,%duration%/3,(%duration%/3)+2)'[v]" -map "[v]" -map 0:a -codec:v libx264 -preset ultrafast -crf 23 -codec:a copy "%~dp0\out\%%~nI.mp4"'
  
  )
  
  endlocal
  
  pause

  Thanks a lot for all the help I’ve received during these days, it really helped me to improve, although I still have a long way to go.

• Anomalie #3624 : Caractères Ҫ dans l’URL réécrite

  29 février 2016, par b b

  Nope, pas de filtre minuscules, mais on pourrait faire comme pour spip_ucfirst et ses sopines, qui appellent init_mb_string (dans laquelle il faudrait ajouter un test sur mb_strtolower) avant d’appliquer les fonction mb_.

  J’ai un doute sur le fait d’ajouter un test sur mb_strtolower dans init_mb_string(), car je vois que spip_ucfirst() utilise mb_strtoupper() qui n’est pas testée dans init_mb_string()...

  Du coup, l’ajout suivant dans inc/charsets serait suffisant ?

  /**
   * Passe une chaîne utf-8 en minuscules
   *
   * Version utf-8 de strtolower
   *
   * @param string $c
   *     La chaîne à transformer
   * @return string
   *     La chaîne en minuscules
   */
  function spip_strtolower($c) 
      // Si ce n’est pas utf-8, utiliser strtolower 
      if ($GLOBALS[’meta’][’charset’] != ’utf-8’) 
          return strtolower($c) ;
      
      // Si on n’a pas mb_* on utilise strtolower
      if (!init_mb_string()) 
          return strtolower($c) ;
      
      return mb_strtolower($c) ;
  
  
  

• ffmpeg convertation imagevideo causes artefacts

  24 mars 2016, par mrgloom

  I want to convert video to images, do some image processing and convert images back to video.

  Here is my commands :

  ./ffmpeg -r 30 -i $VIDEO_NAME "image%d.png"
  
  
  
  ./ffmpeg -r 30 -y -i "image%d.png" output.mpg

  But in output.mpg video I have some artefacts like in jpeg.

  Also I don’t know how to detrmine fps, I set fps=30 (-r 30).
  When I use above first command without -r it produces a lot of images > 1kk, but than I use -r 30 option it produce same number of images as this command calculationg number of frames :

  FRAME_COUNT=`./ffprobe -v error -count_frames -select_streams v:0 -show_entries stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 $VIDEO_NAME`

  So my questions are :

  1. How to determine frame rate ?

  2. How to convert images to video and don’t reduce initial quality ?

  UPDATE :

  Seems this helped, after I removed -r option
  Image sequence to video quality

  so resulting command is :

  ./ffmpeg -y -i "image%d.png" -vcodec mpeg4 -b $BITRATE output_$BITRATE.avi

  but I’m still not sure how to select bitrate.

  How can I see bitrate of original .mp4 file ?