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  • MediaSPIP version 0.1 Beta

    16 avril 2011, par

    MediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

  • MediaSPIP 0.1 Beta version

    25 avril 2011, par

    MediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
    The zip file provided here only contains the sources of MediaSPIP in its standalone version.
    To get a working installation, you must manually install all-software dependencies on the server.
    If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)

  • Amélioration de la version de base

    13 septembre 2013

    Jolie sélection multiple
    Le plugin Chosen permet d’améliorer l’ergonomie des champs de sélection multiple. Voir les deux images suivantes pour comparer.
    Il suffit pour cela d’activer le plugin Chosen (Configuration générale du site > Gestion des plugins), puis de configurer le plugin (Les squelettes > Chosen) en activant l’utilisation de Chosen dans le site public et en spécifiant les éléments de formulaires à améliorer, par exemple select[multiple] pour les listes à sélection multiple (...)

Sur d’autres sites (10550)

  • How to output fragmented mp4 with ffmpeg ?

    4 mars, par S B

    ffmpeg -i infile.avi out.mp4 outputs non-fragmented MP4.

    



    How do I obtain fragmented mp4 ?

    



    Update
A fragmented mp4 file is internally divided into several back-to-back chunks or MPEG-4 movie fragments. Each chunk has its own moof atom - so there are several moof atoms interleaved in the file instead of a single moov at the end as in the case of an unfragmented mp4. This makes it easier to stream over slow networks where buffering is involved

    



    There are several tools like mp4box that convert a normal mp4 to a fragmented one. Unfortunately we cannot use something like this

    



    ffmpeg <options to="to" output="output" mp4="mp4"> | mp4box&#xA;</options>

    &#xA;&#xA;

    since ffmpeg does not produce seekable output while producing mp4 containers.

    &#xA;

  • How to output fragmented mp4 with ffmpeg ?

    12 octobre 2016, par S B

    ffmpeg -i infile.avi out.mp4 outputs non-fragmented MP4.

    How do I obtain fragmented mp4 ?

    Update
    A fragmented mp4 file is internally divided into several back-to-back chunks or MPEG-4 movie fragments. Each chunk has its own moof atom - so there are several moof atoms interleaved in the file instead of a single moov at the end as in the case of an unfragmented mp4. This makes it easier to stream over slow networks where buffering is involved

    There are several tools like mp4box that convert a normal mp4 to a fragmented one. Unfortunately we cannot use something like this

    ffmpeg <options to="to" output="output" mp4="mp4"> | mp4box
    
</options>

    since ffmpeg does not produce seekable output while producing mp4 containers.

  • image -> video -> image not lossless using avconv

    15 décembre 2015, par nrob

    I’m trying to test the amount of information lost with some different video codecs. I’ve got a python script which uses PyPNG to write a series of 8 bit RGB images. I then encode it using avconv, for instance

    avconv -r 1 -i ../frames/data%03d.png -c:v ffv1 -qscale:v 0 -r 1

    outffv1.avi

    I then decode this back into pngs like so

    avconv -r 1 -i outffv1.avi -r 1 ./outffv1/frame%03d.png

    But when I compare the images before and after the video compression, they are different (mean absolute error of 15%). The thing that is confusing me is that this is true (give or take) independent of the codec.

    For instance, I get similar answers for libtheora for a range of qscale values.

    The png encoding i.e. write to png, and immediately load back in without and video compression step, is lossless.

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