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  • Gestion des droits de création et d’édition des objets

    8 février 2011, par

    Par défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;

  • Keeping control of your media in your hands

    13 avril 2011, par

    The vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
    While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
    MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
    MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)

  • Dépôt de média et thèmes par FTP

    31 mai 2013, par

    L’outil MédiaSPIP traite aussi les média transférés par la voie FTP. Si vous préférez déposer par cette voie, récupérez les identifiants d’accès vers votre site MédiaSPIP et utilisez votre client FTP favori.
    Vous trouverez dès le départ les dossiers suivants dans votre espace FTP : config/ : dossier de configuration du site IMG/ : dossier des média déjà traités et en ligne sur le site local/ : répertoire cache du site web themes/ : les thèmes ou les feuilles de style personnalisées tmp/ : dossier de travail (...)

Sur d’autres sites (9782)

  • Crop video into a 4x4 grid/tiles/matrix efficiently via command-line ffmpeg ?

    22 avril 2017, par Dylan

    Hello Stackoverflow community !

    I dread having to ask questions, but there seems to be no efficient way to take a single input video and apply a matrix transformation/split the video into equal sized pieces, preferably 4x4=16 segments per input.

    I tried using all the libraries such as ffmpeg and mencoder, but having 16 outputs can be as slow as 0.15x. The goal of my project is the split the video into 16 segments, rearrange those segments and combine back into a final video ; later reversing the process in HTML5 canvas. Here is a picture to help you understand what I am talking about :
    the source but also the final destination after reorganizing the pieces

    after the segments are exported, I will recombine the pieces in a puzzle manner (they are also inverted and rotated but unrelated)

    I do not believe you can do this all in one command, so my goal is to crop into 16 mapped outputs quickly, then reassemble them in a different order. But I can do the other parts myself. Ideally there would be a way to move pixel blocks eg 100x100 and just move them around. My math is not strong enough..
    I really appreciate the work you guys do !

    admin@dr.com

  • 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 - Overlaying video with transparency, alpha has strange threshold

    3 novembre 2016, 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.

    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.

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