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  • List of compatible distributions

    26 avril 2011, par

    The table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
    If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...)

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • 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 (...)

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  • FFMPEG - Overlaying video with transparency, alpha has strange threshold

    6 mars 2019, par tanker_

    I’m attempting to overlay an Apple ProRes 4444 video with a alpha/transparency onto a normal video. However, upon inspecting the final output from FFMPEG, compared to the same files overlaid on top of one another and rendered in Final Cut Pro, there is a discrepancy in how they render the edges around the object.

    Screenshot comparison :

    Screenshot comparison

    Additional closeup :

    Additional closeup

    Here is my input :

    ffmpeg \
    
    -i background.MOV -x264opts colormatrix=bt709 \
    
    -i alpha_object.MOV -x264opts colormatrix=bt709 \
    
    -filter_complex " \
    
        [0:v]setpts=PTS-STARTPTS, scale=1920x1080[top]; \
    
        [1:v]setpts=PTS-STARTPTS, scale=1920x1080, \
    
             colorchannelmixer=aa=1.0[bottom]; \
    
        [top][bottom]overlay=shortest=1" \
    
    -vcodec libx264 -qp 15 -an -shortest output.MOV

    Any idea what could be wrong ? Is there a option within FFMPEG’s available filters that I’m missing ?

    All files are ingested and rendered in 1920x1080.

  • ffmpeg extract alpha channel from prores

    17 janvier 2019, par vptest

    I’m trying to extract alpha channel from ProRes (mov) in greyscale to a separate mp4 file (to emulate video with transperancy on the html page later).

    ffmpeg -i in.mov -hide_banner -f mp4 -vcodec libx264 -vf alphaextract,format=yuv420p out.mp4

    but I don’t get a filled alpha channel but only a sort of border of it. Pretty sure that original file is ok (tried with different files) and encoding it to webm showed correct transperency.

    What I get from ffmpeg
    enter image description here

    How original file looks like
    enter image description here

  • Is there a way to convert a VP9 webm video into CIELAB colourspace in FFMPEG to improve alpha compositing

    18 août 2022, par OneWorld

    I was wondering if there is an option / command to convert a webm VP9 video into CIELAB colour space in FFMPEG ?

    


    I did a search for CIELAB colour space in FFMPEG and couldn't find anything.

    


    I want to reduce the appearance of black edges by pushing into CIELAB space before doing the overlay / alpha compositing. See this post here :-

    


    moviepy black border around png when compositing into an MP4

    


    How can I do that in FFMPEG ?

    


    Any help would be much appreciated.

    


    Kind regards

    


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