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Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
XMP PHP
13 mai 2011, parDixit Wikipedia, XMP signifie :
Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
XMP permet d’enregistrer sous forme d’un document XML des informations relatives à un fichier : titre, auteur, historique (...) -
(Dés)Activation de fonctionnalités (plugins)
18 février 2011, parPour gérer l’ajout et la suppression de fonctionnalités supplémentaires (ou plugins), MediaSPIP utilise à partir de la version 0.2 SVP.
SVP permet l’activation facile de plugins depuis l’espace de configuration de MediaSPIP.
Pour y accéder, il suffit de se rendre dans l’espace de configuration puis de se rendre sur la page "Gestion des plugins".
MediaSPIP est fourni par défaut avec l’ensemble des plugins dits "compatibles", ils ont été testés et intégrés afin de fonctionner parfaitement avec chaque (...)
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4 Ways to Embed User Privacy & Data Security in Your Business
15 juillet 2022, par Erin — Privacy -
ffprobe to bitrate variable stopped working
6 novembre 2023, par BricktopI have a simple script to encode a video using the same bitrate as the original. I use ffprobe to fetch the bitrate like this :


ffprobe "%file%" -v 0 -select_streams v:0 -show_entries stream=bit_rate -print_format compact=p=0:nokey=1 >%temp%\bitrate.txt



However, while fixing a but in the script where I had an odd number of
"
marks, I suddenly ran into this problem with ffprobe :

Argument ' -v 0 -select_streams v:0 -show_entries stream=bit_rate -print_format compact=p=0:nokey=1 >C:\Users\ADMINI~1\AppData\Local\Temp\bitrate.txt' provided as input filename, but 'D:\VIDEO\AMBIANCE\SCOPITONE\MUSIC TELEVISION\This Here - Calm - OFFICIAL VIDEO (1080p 25fps AV1-128kbit AAC).mp4' was already specified.



I am trying to understand this, scanning insanely for yet another
"
or something in my code but can't figure it out. Here is the full code :

:: write file to queue (first)
move /y "%~dpn0.txt" "%temp%\%~n0.tmp" >nul
echo "%~1" >"%~dpn0.txt"
type "%temp%\%~n0.tmp" >>"%~dpn0.txt"

:: desyncronize instances (todo: try support for adding 9 files at a time)
timeout /t %time:~9,1% /nobreak
:: if not first instance exit
tasklist /fi "imagename eq handbrakecli.exe" | find /i "handbrakecli" && exit
title Transcode

:: delegate queue
for /f "delims=" %%f in (%~dpn0.txt) do (
 set "name=%%~nf"
 set "file=%%~f"
 rem todo: if file has x264 or other video codec mentioned, change to x265
 set "code=%%~dpnf (x265 transcoded)%%~xf"
 call :transcode
)
echo all done!
exit /b

:transcode
title "%name%"
if not exist "%file%" echo %date% %time% source file missing %file% >>%~dpn0.log & goto cleanup
if exist "%code%" echo %date% %time% target file exists %file% >>%~dpn0.log & goto cleanup

:: determine appropriate bitrate (does not seem to work on .webm files, closing the script as a result)
%~dp0ffprobe "%file%" -v 0 -select_streams v:0 -show_entries stream=bit_rate -print_format compact=p=0:nokey=1 >%temp%\bitrate.txt
set /p bitrate=<%temp%\bitrate.txt
:: reduce to full kilobytes
set "bitrate=%bitrate:~0,-3%"
if not defined bitrate echo failed to fetch bitrate & echo %date% %time% no bitrate for %file% >>%~dpn0.log & exit /b
if %bitrate% gtr 7000 set bitrate=7000

:: transcode
%~dp0HandBrakeCLI -i "%file%" -o "%code%" --encoder x265_10bit --encoder-preset slow --encoder-profile main444-10 --vb %bitrate% --two-pass --turbo --audio 1-9 --aencoder copy --audio-copy-mask aac,ac3,mp2,mp3,opus --audio-fallback opus --ab 160 --drc 2.0

:: remove current file from queue, regardless
:cleanup
findstr /v /c:"%file%" "%~dpn0.txt" >"%temp%\%~n0.tmp"
move /y "%temp%\%~n0.tmp" "%~dpn0.txt"



It appears that the
set "file=%%~f"
is the problem, somehow it shows up asset "file=D:\VIDEO\this video here.mp4" "
where the last two characters"
should not belong, and I don't know what to change to fix this.

Every type of improvement to the script is very welcomed !


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Why iFrame is a good idea
15 octobre 2009I’ve seen some hilariously uninformed posts about the new Apple iFrame specification. Let me take a minute to explain what it actually is.
First off, as opposed to what the fellow in the Washington Post writes, it’s not really a new format. iFrame is just a way of using formats that we’ve already know and love. As the name suggests, iFrame is just an i-frame only H.264 specification, using AAC audio. An intraframe version of H.264 eh ? Sounds a lot like AVC-Intra, right ? Exactly. And for exactly the same reasons - edit-ability. Whereas AVC-Intra targets the high end, iFrame targets the low end.
Even when used in intraframe mode, H.264 has some huge advantage over the older intraframe codecs like DV or DVCProHD. For example, significantly better entropy coding, adaptive quantization, and potentially variable bitrates. There are many others. Essentially, it’s what happens when you take DV and spend another 10 years working on making it better. That’s why Panasonic’s AVC-Intra cameras can do DVCProHD quality video at half (or less) the bitrate.
Why does iFrame matter for editing ? Anyone who’s tried to edit video from one of the modern H.264 cameras without first transcoding to an intraframe format has experienced the huge CPU demands and sluggish performance. Behind the scenes it’s even worse. Because interframe H.264 can have very long GOPs, displaying any single frame can rely on dozens or even hundreds of other frames. Because of the complexity of H.264, building these frames is very high-cost. And it’s a variable cost. Decoding the first frame in a GOP is relatively trivial, while decoding the middle B-frame can be hugely expensive.
Programs like iMovie mask that from the user in some cases, but at the expensive of high overhead. But, anyone who’s imported AVC-HD video into Final Cut Pro or iMovie knows that there’s a long "importing" step - behind the scenes, the applications are transcoding your video into an intraframe format, like Apple Intermediate or ProRes. It sort of defeats one of the main purposes of a file-based workflow.
You’ve also probably noticed the amount of time it takes to export a video in an interframe format. Anyone who’s edited HDV in Final Cut Pro has experienced this. With DV, doing an "export to quicktime" is simply a matter of Final Cut Pro rewriting all of the data to disk - it’s essentially a file copy. With HDV, Final Cut Pro has to do a complete reencode of the whole timeline, to fit everything into the new GOP structure. Not only is this time consuming, but it’s essentially a generation loss.
iFrame solves these issues by giving you an intraframe codec, with modern efficiency, which can be decoded by any of the H.264 decoders that we already know and love.
Having this as an optional setting on cameras is a huge step forward for folks interested in editing video. Hopefully some of the manufacturers of AVC-HD cameras will adopt this format as well. I’ll gladly trade a little resolution for instant edit-ability.