Recherche avancée

Médias (91)

Autres articles (66)

  • 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 (...)

  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
    The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
    For older browsers the Flowplayer flash fallback is used.
    MediaSPIP allows for media playback on major mobile platforms with the above (...)

Sur d’autres sites (10139)

  • Converting alpha channel of PNG sequence to Y channel of H265

    31 mai 2018, par Krumelur

    I have a video renderer that expects two H265 streams (YUV420) and I need to bake them to have one of them form an alpha mask to the other one. This is all solved and works well, however if I follow the instructions here :
    ffmpeg splitting RGB and Alpha channels using filter
    the alpha channel is slighly off. My hypothesis is that this is due to the alpha channel being scaled through the RGB->YUV matrix.

    The input is a sequence of PNG files, the output is two MKV files.

    The question is then : How can I tell FFmpeg to “reinterpret” the alpha channel as the Y channel without touching the pixel data ? Ideally by producing both MKV:s in one command line as shown in the other question, but at least without rewriting the source files.

  • (FFMPEG) Make areas transparent before overlaying a vid with perspective

    3 août 2016, par aaeim

    I’m trying to add perspective to a small video then overlay it on top of an other.

    So far I can make the video small, add perspective to it and overlay it to an other video. but after applying the perspective filter, the excess areas don’t turn transparent, they just stretch out the pixels.

    the perspective filter doesn’t have much documentation but as far as i could find out there was no way of setting the extra pixels to transparent.

    So I’m guessing ill need to apply some kind of alpha mask, to the desired area ?

    this is the command I’m using for perspective :

    ffmpeg -i /synced_folder/testvid.mp4 -vf perspective=0:0:W:H/4:0:H:W:3*H/4:0:1:0 /synced_folder/output5.mp4

    Don’t think it matters but I’m running ffmpeg on a VM with centOS.

    This is a SS of how the result looks like :

  • (FFMPEG) Make areas transparent before overlaying a vid with perspective

    7 octobre 2020, par aaeim

    I'm trying to add perspective to a small video then overlay it on top of an other.

    



    So far I can make the video small, add perspective to it and overlay it to an other video. but after applying the perspective filter, the excess areas don't turn transparent, they just stretch out the pixels.

    



    the perspective filter doesn't have much documentation but as far as i could find out there was no way of setting the extra pixels to transparent.

    



    So I'm guessing ill need to apply some kind of alpha mask, to the desired area ?

    



    this is the command I'm using for perspective :

    



    ffmpeg -i /synced_folder/testvid.mp4 -vf perspective=0:0:W:H/4:0:H:W:3*H/4:0:1:0 /synced_folder/output5.mp4


    



    Don't think it matters but I'm running ffmpeg on a VM with centOS.

    



    This is a SS of how the result looks like :

    


Navigation