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  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 is the first MediaSPIP stable release.
    Its official release date is June 21, 2013 and is announced here.
    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 (...)

  • Gestion générale des documents

    13 mai 2011, par

    MédiaSPIP ne modifie jamais le document original mis en ligne.
    Pour chaque document mis en ligne il effectue deux opérations successives : la création d’une version supplémentaire qui peut être facilement consultée en ligne tout en laissant l’original téléchargeable dans le cas où le document original ne peut être lu dans un navigateur Internet ; la récupération des métadonnées du document original pour illustrer textuellement le fichier ;
    Les tableaux ci-dessous expliquent ce que peut faire MédiaSPIP (...)

Sur d’autres sites (7328)

  • FFMPEG X264 reduce bitrate for unchanging input

    8 juin 2021, par GroovyDotCom
    ffmpeg -f lavfi -i smptebars=duration=1000:size=640x360:rate=30 -preset ultrafast -vcodec libx264 -tune zerolatency -b 900k -g 1000 -f mpegts video.ts


    


    As can be seen when running this command, the encode size continues to grow rapidly even though :

    


      

    1. The input source never changes. It is exactly the same image again and again.

      2. 


    2. The encoder has been told to insert a keyframe only once every 1000 frames

      3. 


    


    Is there some configuration option I could add to change this behaviour ? I can understand it would need to send an empty P frame but right now it seems to be sending much much more ?

    


    UPDATE
After Tim Roberts comment, I realized we can get a clearer picture of the file growth if I change the command to 1 FPS and do the encode in real-time.

    


    ffmpeg -f lavfi -re -i smptebars=duration=1000:size=640x360:rate=1 -preset ultrafast -vcodec libx264 -tune zerolatency -b 900k -g 1000 out.ts

    


    Now I see that it is going up almost exactly 1KB per frame. That seems like a lot for a P-frame that does nothing.

    


    So, just for kicks, I got rid of the TS muxing.

    


    ffmpeg -f lavfi -re -i smptebars=duration=1000:size=640x360:rate=1 -preset ultrafast -vcodec libx264 -tune zerolatency -b 900k -g 1000 out.h264

    


    Now the file grows by 1k every 17 frames - a 17X improvement !

    


    This seems to point to ffmpeg doing something weird in the TS muxer that inflates an 80 byte P-frame into 1K.

    


  • FFMPEG X264 reduce bitrate for unchanging input

    8 juin 2021, par GroovyDotCom
    ffmpeg -f lavfi -i smptebars=duration=1000:size=640x360:rate=30 -preset ultrafast -vcodec libx264 -tune zerolatency -b 900k -g 1000 -f mpegts video.ts


    


    As can be seen when running this command, the encode size continues to grow rapidly even though :

    


      

    1. The input source never changes. It is exactly the same image again and again.

      2. 


    2. The encoder has been told to insert a keyframe only once every 1000 frames

      3. 


    


    Is there some configuration option I could add to change this behaviour ? I can understand it would need to send an empty P frame but right now it seems to be sending much much more ?

    


    UPDATE
After Tim Roberts comment, I realized we can get a clearer picture of the file growth if I change the command to 1 FPS and do the encode in real-time.

    


    ffmpeg -f lavfi -re -i smptebars=duration=1000:size=640x360:rate=1 -preset ultrafast -vcodec libx264 -tune zerolatency -b 900k -g 1000 out.ts

    


    Now I see that it is going up almost exactly 1KB per frame. That seems like a lot for a P-frame that does nothing.

    


    So, just for kicks, I got rid of the TS muxing.

    


    ffmpeg -f lavfi -re -i smptebars=duration=1000:size=640x360:rate=1 -preset ultrafast -vcodec libx264 -tune zerolatency -b 900k -g 1000 out.h264

    


    Now the file grows by 1k every 17 frames - a 17X improvement !

    


    This seems to point to ffmpeg doing something weird in the TS muxer that inflates an 80 byte P-frame into 1K.

    


  • Revision 74427 : On va changer la méthode pour trouver plugin.xml et paquet.xml. On ...

    22 juillet 2013, par teddy.spip@… — Log

    On va changer la méthode pour trouver plugin.xml et paquet.xml. On passe par la class php RecursiveDirectoryIterator ? et RecursiveIteratorIterator ?. Cela devrait prendre en compte ’toutes’ les profondeurs où peuvent se trouver les plugins mutualisés. Ne prend pas en compte pour le moment _DIR_PLUGINS_SUPP.
    Cette astuce vient de ma discussion sur ​http://forum.alsacreations.com/topic.php?tid=68023&fid=20
    Merci à eux.

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