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  • 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 (...)

  • Multilang : améliorer l’interface pour les blocs multilingues

    18 février 2011, par

    Multilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
    Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela.

  • ANNEXE : Les plugins utilisés spécifiquement pour la ferme

    5 mars 2010, par

    Le site central/maître de la ferme a besoin d’utiliser plusieurs plugins supplémentaires vis à vis des canaux pour son bon fonctionnement. le plugin Gestion de la mutualisation ; le plugin inscription3 pour gérer les inscriptions et les demandes de création d’instance de mutualisation dès l’inscription des utilisateurs ; le plugin verifier qui fournit une API de vérification des champs (utilisé par inscription3) ; le plugin champs extras v2 nécessité par inscription3 (...)

Sur d’autres sites (3871)

  • Compressing videos from a smartphone

    9 novembre 2016, par fejesjoco

    I have a Nexus 6p with the stock camera. It’s set to record at 1080p, 30fps. Here’s a 5 second sample (11 MB).

    Videos from this phone come out at about 17 Mbps on average. I tried to compress it with ffmpeg with -c:v libx264 -crf 23 -preset veryslow, the result comes out at about 5.5 MB, which is about 9 Mbps.

    I think this bitrate is a bit too much. When I look at torrent file listings, I can see high quality videos at 3 GB in size on average, and if such a movie is 90 minutes long on average, that is about 4-5 Mbps which sounds okay.

    I’m wondering, why the big difference ? I can notice that my video is noisy/grainy (which is expected from a phone), and that might reduce compressibility. I tried a few ffmpeg filters, like hqdn3d and atadenoise, but the noise mostly remained (maybe I didn’t play with it enough). Then I figured, the video is also shaky (which is also expected), and that might reduce compressibility too (and even makes temporal noise filtering less effective). I tried to stabilize it with the deshake filter, but that didn’t help either.

    I know I could just limit the bandwidth to whatever I like, but there must be a reason why ffmpeg thinks it needs a high bandwidth to maintain a certain quality, and a lower bandwidth would just decrease the quality.

    Why do these videos have such a high bitrate ? What’s the best way to compress them more while keeping or even increasing their quality ?

  • Use ffmpeg to resize one input's dimension to match another input's dimension

    18 novembre 2022, par Hans GD

    I need to resize one image A to match one dimension of another input B (make height of A match the height of B, for example). I will do this for several pairs of images in a folder, for which I will use a script in the end, but I wanted to know if this particular operation can be done only with ffmpeg.

    


    Again, the final script could read the image, find the size and use scale=-1:height to accomplish the final goal, but is it posible to make the title's operation only with ffmpeg ?

    


  • Create 256 color palette video

    2 mars 2020, par rlcabral

    I already have this working by converting the source video to GIF with :

    ffmpeg -y -t 5 source.mp4 -vf fps=10,scale=480:-1,smartblur=ls=-0.5,crop=iw:ih-2:0:0 -hide_banner -loglevel panic output.gif

    And then converting the GIF to MP4, like so :

    ffmpeg -y animated.gif -hide_banner -pix_fmt yuvj420p -loglevel panic -an -loglevel panic final.mp4

    What I want is to convert source.mp4 directly to final.mp4, and have the same 256 color palette as a normal GIF.

    I tried merging both commands together, and although it generates a MP4, the result is a 16 bit video, surprisingly smaller than a 8 bit video.

    Do I need to generate a palette first with palettegen and then re-encode the video with this palette ?

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