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• Evolution #4779 (Nouveau) : Déclarer fonctions variadiques au lieu d’utiliser func_get_args

  9 mai 2021, par jluc -

  PHP recommande de ne pas utiliser func_get_args mais de déclarer explicitement comme variadiques les fonctions, en passant les arguments avec "...", au lieu de les récupérer avec func_get_args. cf https://www.php.net/manual/fr/functions.arguments.php#functions.variable-arg-list en français pas toujours bien traduit, ou https://www.php.net/manual/en/functions.arguments.php#functions.variable-arg-list en anglais.

  Exemple : remplacer l’actuel :
  

  function concat()  $args = func_get_args() ; return join(’’, $args) ; 
  

  
  par
  

  function concat (...$args) return join(’’, $args) ; 
  

  Rq : Il faut la syntaxe "..." pour que isVariadic() renvoie true. Ça augmente les capacités d’introspection. Utile par exemple pour #4717 + https://git.spip.net/spip/spip/pulls/160

• How to batch process a series of video files with powershell and other-transcode/ffmpeg

  7 juin 2022, par DarkDiamond

  TL ;DR

  


  What did I do wrong in the following PowerShell-Script ? It does not work as expected.

  


  ---

  


  I am recording some of my lectures in my university with a photo camera. This works pretty well although I have to split the single lecture into three to four parts because the camera can only record 29 minutes of video in one take. I know that this is a common issue related to some licensensing problem that most photo cameras simply don't have the right license to record longer videos. But it confronts me with the problem that I later have to edit the files together after I did some post processing on them.

  


  With the camera I produce up to four video files with sizes around 3.5 GB which is way to big in order to be of any use because our IT department understandably doesn't want to host so much data, as I produce around 22 GB of video material each week.

  


  Some time ago I came across a very useful tool called "other-video-transcoding" by Don Melton over on GitHub, written in ruby, that allows me to compress the files to a reasonable file size without any visual loss. In addition I crop the videos to remove the part of each frame that is neither the board nor a place where my professor stands in order to decrease the filesize even further and do some privacy protection by cutting out most of the students.

  


  As the tools are accessable via the command line, it is relatively easy to configure and does not cost additional computational power to render a nice gui, so I can edit one of the 29 minute clips in less than 10 minutes.

  


  Now I wanted to optimize my workflow by writing a PowerShell script that only takes the parameters what to crop and which files to work on and then does the rest on its own so I can just start the script and then do something else while my laptop renders the new files.

  


  So far I have the following :

  


  $video_path = Get-ChildItem ..\ -Directory | findstr "SoSe"

Get-ChildItem $video_path -name | findstr ".MP4" | Out-File temp.txt -Append 
Get-Content temp.txt | ForEach-Object {"file " + $_} >> .\files.txt

Get-ChildItem $video_path |
Foreach-Object {
other-transcode --hevc --mp4 --target 3000 --crop 1920:780:0:0 $_.FullName
}

#other-transcode --hevc --mp4 --crop 1920:720:60:0 ..\SoSe22_Theo1_videos_v14_RAW\
ffmpeg -f concat -i files.txt -c copy merged.mp4
Remove-Item .\temp.txt


  


  but it does not quite do what I it expect to do.
This is my file system :

  


  sciebo/
└── SoSe22_Theo1_videos/
    ├── SoSe22_Theo1_videos_v16/
    │   ├── SoSe22_Theo1_videos_v16_KOMPR/
    │   │   ├── C0001.mp4
    │   │   ├── C0002.mp4
    │   │   ├── C0003.mp4
    │   │   ├── C0004.mp4
    │   │   ├── temp.txt
    │   │   ├── files.txt
    │   │   └── merged.mp4
    │   └── SoSe22_Theo1_videos_v16_RAW/
    │       ├── C0001.mp4
    │       ├── C0002.mp4
    │       ├── C0003.mp4
    │       └── C0004.mp4
    └── SoSe22_Theo1_videos_v17/
        ├── SoSe22_Theo1_videos_v17_KOMPR
        └── SoSe22_Theo1_videos_v17_RAW/
            ├── C0006.mp4
            ├── C0007.mp4
            ├── C0008.mp4
            └── C0009.mp4


  


  where the 16th lecture is already processed and the 17th is not. I always have the raw video data in the folders ending on RAW and the edited/compressed output files in the one ending on KOMPR. Note that the video files in the KOMPR folder are the output files of the other-transcode tool.

  


  The real work happens in the line where it says

  


  other-transcode --hevc --mp4 --target 3000 --crop 1920:780:0:0 $_.FullName


  


  and in the line

  


  ffmpeg -f concat -i files.txt -c copy merged.mp4


  


  where I concat the output files into the final version I can upload to our online learning platform.
What is wrong with my script ? In the end I'd like to pass the --crop parameter just to my script, but that is not the primary problem.

  


  ---

  


  A little information on the transcoding script so you don't have to look into the documentation :
  
As the last argument the tool takes the location of the video files to work on, be it relative or absolute file paths. The output is placed in the folder the script is called in, so if I cd into one of the KOMPR directories and then call

  


  other-transcode --mp4 ../SoSe22_Theo1_videos_v16_RAW/C0001.mp4


  


  a new file C0001.mp4 is created in the KOMPR directory and the transcoded video and old audio are written to that new video file.

  


• NAB 2010 wrapup

  15 avril 2010

  Another year of NAB has come and gone. Making it out of Vegas with some remaining faith in humanity seems like a successful outcome. So, anything worth talking about at the show ?

  First off, there’s 3d. 3D is The Next Big Thing, and that was obvious to anyone who spent half a second on the show floor. Everything from camera rigs, to post production apps, to display technology was all 3d, all the time. I’m not a huge fan of 3d in most cases, but the industry is at least feigning interest.

  Luckily, at a show as big as NAB, there’s plenty of other cool stuff to see. So, what struck my fancy ?

  First off, Avid and Adobe were showing new versions of Media Composer and Premiere. Both sounded pretty amazing on paper, but I must say I was somewhat underwhelmed by both in reality. Premiere felt a little rough around the edges - the Mercurial Engine wasn’t the sort of next generation tech that I expected. Media Composer 5 has some nice new tweaks, but it’s still rather Avid-y - which is good for Avid people, less interesting for the rest of us.

  In other software news, Blackmagic Design was showing off some of what they’re doing with the DaVinci technology that they acquired. Software-only Da Vinci Resolve for $999 is a pretty amazing deal, and the demos were quite nice. That said, color correction is an art, so just making the technology cheaper isn’t necessarily going to dramatically change the number of folks who do it well - see Color.

  Blackmagic also has a pile of new USB 3.0 hardware devices, including the absolutely gorgeous UltraStudio Pro. Makes me pine for USB 3.0 on the mac.

  On the production side, we saw new cameras from just about everyone. To start at the high end, the Arri Alexa was absolutely stunning. Perhaps the nicest digital cinema footage I’ve seen. Not only that, but they’ve worked out a usable workflow, recording to ProRes plus RAW. At the price point they’re promising, the world is going to get a lot more difficult for RED.

  Sony’s new XDCam EX gear is another good step forward for that format. Nothing groundbreaking, but another nice progression. I was kind of hoping we’d see 4:2:2 EX gear from them, but I suppose they need to justify the disc based formats for a while longer.

  The Panasonic AG-AF100 is another interesting camera, bringing micro 4/3rds into video. The only strange thing is the recording side - AVCHD to SD cards. While I’m thrilled to see them using SD instead of P2, it sure would have been nice to have an AVCIntra option.

  Finally, Canon’s 4:2:2 XF cams are a nice option for the ENG/EFP market. Nothing groundbreaking, aside from the extra color sampling, but it’s a nice step up from what they’ve been doing.

  Speaking of Canon, it’s interesting to see the ways that the 5d and 7d have made their way into mainstream filmmaking. At one point, I thought they’d be relegated to the indie community - folks looking for nice DoF on a budget. Instead, they seem to have been adopted by a huge range of productions, from episodic TV to features. While they’re not right for everyone, the price and quality make them an easy choice in many cases.

  One of the stars of the show for me was the GoPro, a small waterproof HD camera that ships with a variety of mounts, designed to be used in places where you couldn’t or wouldn’t use a more full featured camera. No LCD, just a record button and a wide angle lens. I bought two.

  Those are the things that stand out for me. While there was plenty of interesting stuff to be seen, given the current economic conditions at the University, I wasn’t exactly in a shopping mindset. The show definitely felt more optimistic than it did last year, and companies are again pushing out new products. However, attendances was about 20% lower than 2008, and that was definitely noticeable on the show floor.