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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (71)
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Creating farms of unique websites
13 avril 2011, parMediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...) -
Contribute to a better visual interface
13 avril 2011MediaSPIP is based on a system of themes and templates. Templates define the placement of information on the page, and can be adapted to a wide range of uses. Themes define the overall graphic appearance of the site.
Anyone can submit a new graphic theme or template and make it available to the MediaSPIP community. -
Support de tous types de médias
10 avril 2011Contrairement à beaucoup de logiciels et autres plate-formes modernes de partage de documents, MediaSPIP a l’ambition de gérer un maximum de formats de documents différents qu’ils soient de type : images (png, gif, jpg, bmp et autres...) ; audio (MP3, Ogg, Wav et autres...) ; vidéo (Avi, MP4, Ogv, mpg, mov, wmv et autres...) ; contenu textuel, code ou autres (open office, microsoft office (tableur, présentation), web (html, css), LaTeX, Google Earth) (...)
Sur d’autres sites (8062)
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Noobs approach to automate x264 cmd
16 novembre 2012, par nightcrawlerso here is my script to loop through specific video extensions » add a manual profile » generate necessary *.bat & finally a final 'loader' batch file to execute previous *.bat files sequentially & necessary logging (this gives quiet a deal of freedom if you so want)
::==
:: gets lines into vars c1 v2 v...
@echo off
:: user input required
cd /d "d:\Trainers\out\"
setLocal EnableDelayedExpansion
dir /B /O:N | findstr ".wmv$ " >filename.txt
echo. >log.txt
:: user input required
for /f "tokens=* delims= " %%a in ('type filename.txt ^|findstr ".wmv$"') do (
set /a n+=1
echo. >file!n!.bat
set in=%in%%%a
:: user input required
set out=!in:.wmv=.mp4!
:: user input required
set v=x264 --crf 23 --level 3.1 --tune film -o "d:\Trainers\out\!in!" "d:\Trainers\out\!out!"
echo. !v!>file!n!.bat
)
dir /B /O:N | findstr ".bat$ " >x264_home.txt
for /f "tokens=* delims= " %%a in (x264_home.txt) do (
set /a n+=1
:: mtee is an external library Google it
set "z=call %%a | mtee /d/c/t/+ log.txt"
echo. !z! >> x264_home.bat
)
echo. @echo off > newFile.bat
type x264_home.bat >> newFile.bat
type newFile.bat > x264_home.bat
del newFile.bat,x264_home.txt,filename.txt
echo. pause >> x264_home.bat
echo. @echo All Operation done... >> x264_home.bat
:: user input required
move "d:\Trainers\out\*.bat" "d:\Program Files\x264_auto\test\"
:: user input required
move "d:\Trainers\out\log.txt" "d:\Program Files\x264_auto\test\"
::==Now the above code which is fairly easy to understand (bcz its written by a noob) run perfectly & create necessary files. For instance one of the file1.bat looks like this :
x264 --crf 23 --level 3.1 --tune film --preset veryslow --deblock -2:-1 --zones 24233,25324,q=20 --acodec aac --abitrate 80 -o "d:\Trainers\out\1.wmv" "d:\Trainers\out\1.mp4"
...& the loader .bat file looks like
@echo off
call file1.bat | mtee /d/c/t/+ log.txt
call file2.bat | mtee /d/c/t/+ log.txt
call file3.bat | mtee /d/c/t/+ log.txt
@echo All Operation done...You see this is a quiet flexible approach in that you can use special filestr » set another loop » set another profile. Furthermore every batch file can be latter edited especiialy when you heavily use
--zone
x264 feature
I am successful because there is no error in any output ...but its the x264.exe (provider/compiler x264GUI) throws error which it otherwise don't ?d:\Program Files\x264_auto\test>x264 --crf 23 --level 3.1 --tune film --preset
veryslow --deblock -2:-1 --zones 24233,25324,q=20 --acodec aac --abitrate 80 -o
"d:\Trainers\out\1.wmv" "d:\Trainers\out\1.mp4"
ffms [error]: could not create index
lavf [error]: could not open input file
raw [error]: raw input requires a resolution.
x264 [error]: could not open input file `d:\Trainers\out\1.mp4' via any method!its the x264 thats the culprit perhaps a senior guide is required here
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Révision 21953 : Limiter l’impact d’un GoneAway Mysql lors de longues requetes PHP
19 mars 2015, par gitosis- Si un traitement de page est long et implique plusieurs requetes SQL, Mysql peut retourner une erreur 2006 (Gone Away) pour la requete en cours et pour toutes les autres qui vont suivre dans le même processus
- Pour limiter l’impact d’un tel blocage, on relance une connexion Mysql vierge
Parmi les cas d’usages on peut noter ceux qui traitent en masse les données du site pour une indexation annexe
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More Cinepak Madness
20 octobre 2011, par Multimedia Mike — Codec TechnologyFellow digital archaeologist Clone2727 found a possible fifth variant of the Cinepak video codec. He asked me if I cared to investigate the sample. I assured him I wouldn’t be able to die a happy multimedia nerd unless I have cataloged all possible Cinepak variants known to exist in the wild. I’m sure there are chemistry nerds out there who are ecstatic when another element is added to the periodic table. Well, that’s me, except with weird multimedia formats.
Background
Cinepak is a video codec that saw widespread use in the early days of digital multimedia. To date, we have cataloged 4 variants of Cinepak in the wild. This distinction is useful when trying to write and maintain an all-in-one decoder. The variants are :- The standard type : Most Cinepak data falls into this category. It decodes to a modified/simplified YUV 4:2:0 planar colorspace and is often seen in AVI and QuickTime/MOV files.
- 8-bit greyscale : Essentially the same as the standard type but with only a Y plane. This has only been identified in AVI files and is distinguished by the file header’s video bits/pixel field being set to 8 instead of 24.
- 8-bit paletted : Again, this is identified by the video header specifying 8 bits/pixel for a Cinepak stream. There is essentially only a Y plane in the data, however, each 8-bit value is a palette index. The palette is transported along with the video header. To date, only one known sample of this format has even been spotted in the wild, and it’s classified as NSFW. It is also a QuickTime/MOV file.
- Sega/FILM CPK data : Sega Saturn games often used CPK files which stored a variant of Cinepak that, while very close the standard Cinepak, couldn’t be decoded with standard decoder components.
So, a flexible Cinepak decoder has to identify if the file’s video header specified 8 bits/pixel. How does it distinguish between greyscale and paletted ? If a file is paletted, a custom palette should have been included with the video header. Thus, if video bits/pixel is 8 and a palette is present, use paletted ; else, use greyscale. Beyond that, the Cinepak decoder has a heuristic to determine how to handle the standard type of data, which might deviate slightly if it comes from a Sega CPK file.
The Fifth Variant ?
Now, regarding this fifth variant– the reason this issue came up is because of that aforementioned heuristic. Basically, a Cinepak chunk is supposed to store the length of the entire chunk in its header. The data from a Sega CPK file plays fast and loose with this chunk size and the discrepancy makes it easy to determine if the data requires special handling. However, a handful of files discovered on a Macintosh game called “The Journeyman Project : Pegasus Prime” have chunk lengths which are sometimes in disagreement with the lengths reported in the containing QuickTime file’s stsz atom. This trips the heuristic and tries to apply the CPK rules against Cinepak data which, aside from the weird chunk length, is perfectly compliant.Here are the first few chunk sizes, as reported by the file header (stsz atom) and the chunk :
size from stsz = 7880 (0x1EC8) ; from header = 3940 (0xF64) size from stsz = 3940 (0xF64) ; from header = 3940 (0xF64) size from stsz = 15792 (0x3DB0) ; from header = 3948 (0xF6C) size from stsz = 11844 (0x2E44) ; from header = 3948 (0xF6C)
Hey, there’s a pattern here. If they don’t match, then the stsz size is an even multiple of the chunk size (2x, 3x, or 4x in my observation). I suppose I could revise the heuristic to state that if the stsz size is 2x, 3x, 4x, or equal to the chunk header, qualify it as compliant Cinepak data.
Of course it feels impure, but software engineering is rarely about programmatic purity. A decade of special cases in the FFmpeg / Libav codebases are a testament to that.
What’s A Variant ?
Suddenly, I find myself contemplating what truly constitutes a variant. Maybe this was just a broken encoder program making these files ? And for that, I assign it the designation of distinct variation, like some sort of special, unique showflake ?Then again, I documented Magic Carpet FLIC as being a distinct variant of the broader FLIC format (which has an enormous number of variants as well).