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  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

  • Gestion de la ferme

    2 mars 2010, par

    La ferme est gérée dans son ensemble par des "super admins".
    Certains réglages peuvent être fais afin de réguler les besoins des différents canaux.
    Dans un premier temps il utilise le plugin "Gestion de mutualisation"

  • 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 (11473)

  • Insert keyframe into m4v/mp4 at specific times

    31 janvier 2024, par reynoldsnlp

    I have a program for educators (written with electronjs framework) that plays videos, skipping to preset points in the video as defined in a companion JSON file. Sometimes there is a significant lag after a skip, and this answer suggests that the lag is there because of infrequent keyframes.

    



    Assuming this is correct, I would like to insert keyframes at exact points in the mp4 file where I know the player will skip to. However, some of these video files are already quite large, so I do not want to decrease the keyframe interval, thereby making the files even larger. I only need to force a handful of keyframes in the entire file.

    



    I would like to be able to pass an argument (to ffmpeg, for example) with the times at which I want to force keyframes. Preferably, I would like to do this without re-encoding the entire video (just like this unanswered question), but if I have to reencode the video, I could do that too.

    


  • matroskaenc : Validate chapter start and end times

    3 février 2015, par Vittorio Giovara
    matroskaenc : Validate chapter start and end times

    CC : libav-stable@libav.org
    
Bug-Id : CID 1265717
    • [DH] libavformat/matroskaenc.c

  • FFmpeg Fade in and out video multiple times

    26 mars 2020, par UsuallyHelpless

    I need to overlay a video multiple times. Let’s say that the overlay video is visible between 2-5 and 7-9 seconds with fading.

     :

    (Works) : Single fade in/out between 2-5 :

    ffmpeg -i background.mp4 -i overlay.mp4 -filter_complex "[1:v]fade=in:st=2:d=1,fade=out:st=4:d=1[ovrl];[0][ovrl]overlay" out.mp4

    (Doesn’t work) Double fade in/out between 2-5 and 7-9

    ffmpeg -i background.mp4 -i overlay.mp4 -filter_complex "[1:v]format=rgba,fade=in:st=2:d=1,fade=out:st=4:d=1,fade=in:st=7:d=1,fade=out:st=8:d=1[ovrl];[0][ovrl]overlay" out.mp4

    This makes the whole overlay video not appear at all. Not even in the first fade in/out.

     :

    Do I need to use the "enable(t,2,5)" ?

    Or is it possible I need to somehow use the "overlay=alpha=" filter option ?

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