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• Révision 23678 : Bugfix dans recup_date() quand on lui passe une chaîne du type 2017-07

  20 juillet 2017, par brunobergot@gmail.com

  Sous PHP 5.5.38-1 le test `substr($jour, 0, 1) == ’0’` renvoie true quand `$jour = ’’` ce qui fait renvoyer un valeur false pour le jour au lieu d’une chaîne vide.
  r23409 ayant modifié affdate_base(), ce cas ne passait plus par `strtotime($numdate)` mais par `mktime($heures, $minutes, $secondes, $mois, $jour, $annee)` qui génère un timestamp décalé d’un jour en arrière.
  On obtenait donc 06 au lieu de 07 pour `[(#VAL2017-07|affdatem)]`

  pfiou :p

• FFmpeg : chromakey without green edges

  5 septembre 2020, par Igniter

  I have a video of a person on green background and I'm trying to turn background transparent by this :

  


  ffmpeg -i bg.mp4 -i man.mp4 -filter_complex '[1:v]colorkey=0x00ff00:0.3:0.3[ckout];[0:v][ckout]overlay[out]' -map '[out]' result.mp4


  


  Colorkey gives this quite noticeable green edge around the person's figure.
  
Any attempts to increase opacity or blend parameters result in disappearing facial features.

  


  

  


  Is there any smart way to change pure green 0x00ff00 pixels with transparent ones ?

  


• FFMPEG and AWS : What's the most efficient way to handle this ?

  28 mai 2022, par Red Vic

  I'm new to AWS and I originally built the FFmpeg functions on my Node.JS API. But I realized this is the wrong way to do it in a real-world app, and that you need to use separate Lambda functions in AWS that handle the video editing separately from the main server.

  


  I'm mainly a front-end developer but I'm open to learning new things.

  


  I basically have the following process in my app :

  


  

  • User uploads video.

  


  • I need to take that video and add a watermark to it.

  


  • I then need a copy of the watermarked video in a smaller resolution.

  


  • I then need a 6 seconds GIF of the smaller resolution video.

  


  • Finally, I need to upload the 3 edited files (2 .mp4's and 1 .gif) to S3, and remove the original, non-watermarked video.

  


  


  Here are my questions to be clear :

  


  

  • Should I upload the original file to S3 or to the server ? And why ?

  


  • Is the process above doable in a single Lambda function ? Or do I need more Lambda functions ?

  


  • How would you handle this problem, personally ?

  


  


  I originally built it by chaining one function to the next with promises, but AWS seems like a different world of doing things and the way I originally built it would not work.

  


  Thanks a lot.

  


  Update
Here are some tests I did with a couple videos :

  


  





  


  


  


  


  


  


  


  


  



  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  


  	Test 1	Test 2	Test 3	Test 4	Test 5
  Original video resolution	1080p	1080p	1080p	1080p	480p
  Original video duration	23 minutes	15 minutes	11 minutes	3.5 minutes	5 minutes
  Step 1 duration (Watermarking original video)	30 minutes	18 minutes	14 minutes	4 minutes	2 minutes
  Step 2 duration (Watermarking lower resolution)	5 minutes	3 minutes	3 minutes	1 minute	skip (already low res)
  Step 3 duration (6 seconds GIF creation)	negligible (15 seconds)	negligible (10 seconds)	negligible (7 seconds)	negligible	negligible
  Total	35 minutes	21 minutes	17 minutes	5 minutes	2 minutes