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  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • La sauvegarde automatique de canaux SPIP

    1er avril 2010, par

    Dans le cadre de la mise en place d’une plateforme ouverte, il est important pour les hébergeurs de pouvoir disposer de sauvegardes assez régulières pour parer à tout problème éventuel.
    Pour réaliser cette tâche on se base sur deux plugins SPIP : Saveauto qui permet une sauvegarde régulière de la base de donnée sous la forme d’un dump mysql (utilisable dans phpmyadmin) mes_fichiers_2 qui permet de réaliser une archive au format zip des données importantes du site (les documents, les éléments (...)

  • Configuration spécifique d’Apache

    4 février 2011, par

    Modules spécifiques
    Pour la configuration d’Apache, il est conseillé d’activer certains modules non spécifiques à MediaSPIP, mais permettant d’améliorer les performances : mod_deflate et mod_headers pour compresser automatiquement via Apache les pages. Cf ce tutoriel ; mode_expires pour gérer correctement l’expiration des hits. Cf ce tutoriel ;
    Il est également conseillé d’ajouter la prise en charge par apache du mime-type pour les fichiers WebM comme indiqué dans ce tutoriel.
    Création d’un (...)

Sur d’autres sites (5945)

  • arm : implement x264_pixel_var_8x16_neon

    12 mars 2014, par Janne Grunau
    arm : implement x264_pixel_var_8x16_neon

    checkasm —bench on a cortex-a9 :
    
var_8x16_c : 4306
    
var_8x16_neon : 791
    • [DH] common/arm/pixel-a.S
    • [DH] common/arm/pixel.h
    • [DH] common/pixel.c

  • What’s So Hard About Building ?

    10 septembre 2011, par Multimedia Mike — Programming

    I finally had a revelation as to why so building software can be so difficult– because build systems are typically built on programming languages that you don’t normally use in your day to day programming activities. If the project is simple enough, the build system usually takes care of the complexities. If there are subtle complexities — and there always are — then you can to figure out how to customize the build system to meet your needs.

    First, there’s the Makefile. It’s easy to forget that the syntax which comprises a Makefile pretty well qualifies as a programming language. I wonder if it’s Turing-complete ? But writing and maintaining Makefiles manually is arduous and many systems have been created to generate Makefiles for you. At the end of the day, running ‘make’ still requires the presence of a Makefile and in the worst case scenario, you’re going to have to inspect and debug what was automatically generated for that Makefile.

    So there is the widespread GNU build system, a.k.a., “the autotools”, named due to its principle components such as autoconf and automake. In this situation, you have no fewer than 3 distinct languages at work. You write your general build instructions using a set of m4 macros (language #1). These get processed by the autotools in order to generate a shell script (language #2) called configure. When this is executed by the user, it eventually generates a Makefile (language #3).

    Over the years, a few challengers have attempted to dethrone autotools. One is CMake which configures a project using its own custom programming language that you will need to learn. Configuration generates a standard Makefile. So there are 2 languages involved in this approach.

    Another option is SCons, which is Python-based, top to bottom. Only one programming language is involved in the build system ; there’s no Makefile generated and run. Until I started writing this, I was guessing that the Python component generated a Makefile, but no.

    That actually makes SCons look fairly desirable, at least if your only metric when choosing a build system is to minimize friction against rarely-used programming languages.

    I should also make mention of a few others : Apache Ant is a build system in which the build process is described by an XML file. XML doesn’t qualify as a programming language (though that apparently doesn’t stop some people from using it as such). I see there’s also qmake, related to the Qt system. This system uses its own custom syntax.

  • arm : add ff_int32_to_float_fmul_array8_neon

    3 décembre 2015, par Janne Grunau
    arm : add ff_int32_to_float_fmul_array8_neon

    Quite a bit faster than int32_to_float_fmul_array8_c calling
    
ff_int32_to_float_fmul_scalar_neon through FmtConvertContext.
    
Number of cycles per int32_to_float_fmul_array8 call while decoding
    
padded.dts on exynos5422 :
    

                   before  after   change
    
cortex-a7 :     1270     951    -25%
    
cortex-a15 :     434     285    -34%
    

    checkasm —bench cycle counts :     cortex-a15   cortex-a7
    
int32_to_float_fmul_array8_c :      1730.4       4384.5
    
int32_to_float_fmul_array8_neon_c :  571.5       1694.3
    
int32_to_float_fmul_array8_neon :    374.0       1448.8
    

    Interesting are the differences between
    
int32_to_float_fmul_array8_neon_c and int32_to_float_fmul_array8_neon.
    
The former is current behaviour of calling
    
ff_int32_to_float_fmul_scalar_neon repeatedly from the c function,
    
The raw numbers differ since checkasm uses different lengths than the
    
dca decoder.
    • [DBH] libavcodec/arm/fmtconvert_init_arm.c
    • [DBH] libavcodec/arm/fmtconvert_neon.S

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