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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 ;

  • 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 (...)

  • 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 (...)

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  • Encode h264 to match existing stream

    6 juin 2013, par Diego Sánchez

    In short : I have to encode a tiny amount of video frames and stitch them in front of a much bigger h.264 stream without reencoding said stream.

    The details : I receive a multi GB transport stream containing a h.264 es and an audio es. Currently the h.264 streams are always generated using x264, and I can assume this will be the case in the future. Now I have to prepend some video frames to this stream, but am not allowed to decode/encode the whole stream ; which leaves me with the only option to find out the exact parameters I need to pass x264_encoder_open so both streams match.

    Currently what I'm doing is :

    1. Demux the original ts and extract h.264 NAL packets.
    2. When I find the first "user data unregistered" SEI packet, I parse it and find a bunch of x264 parameters.
    3. Use libavcodec to start decoding the video. That gives me the dimensions of the picture and the h264 profile and level in the AVCodecContext structure.
    4. Match all of that as best as I can in the x264_param_t structure.

    I can do some encoding with that, and the encoded video plays correctly up to the join point. When VLC is reaching the stitch point it starts throwing out the following sequence of messages and soon after stops playing :

    [h264 @ 0x7fe36cd75be0] decode_slice_header error
    
[h264 @ 0x7fe36cd75be0] no frame!
    
[h264 @ 0x7fe36ccc9080] Width/height changing with threads is not implemented. Update your Libav version to the newest one from Git. If the problem still occurs, it means that your file has a feature which has not been implemented.

    which clearly shows that my encoded frames do not match the original ones. I've been browsing the source code and can't seem to find a way of doing this. What I have currently (besides not working), involves a lot of guesswork, so even if I could make it work with the handful of example files I have, I would be scared to deploy this in production servers.

    So the obvious question is : Is there a safe, formal way of doing this ?

    Thanks in Advance

  • Encode h264 to match existing stream

    6 juin 2013, par Diego Sánchez

    In short : I have to encode a tiny amount of video frames and stitch them in front of a much bigger h.264 stream without reencoding said stream.

    The details : I receive a multi GB transport stream containing a h.264 es and an audio es. Currently the h.264 streams are always generated using x264, and I can assume this will be the case in the future. Now I have to prepend some video frames to this stream, but am not allowed to decode/encode the whole stream ; which leaves me with the only option to find out the exact parameters I need to pass x264_encoder_open so both streams match.

    Currently what I'm doing is :

    1. Demux the original ts and extract h.264 NAL packets.
    2. When I find the first "user data unregistered" SEI packet, I parse it and find a bunch of x264 parameters.
    3. Use libavcodec to start decoding the video. That gives me the dimensions of the picture and the h264 profile and level in the AVCodecContext structure.
    4. Match all of that as best as I can in the x264_param_t structure.

    I can do some encoding with that, and the encoded video plays correctly up to the join point. When VLC is reaching the stitch point it starts throwing out the following sequence of messages and soon after stops playing :

    [h264 @ 0x7fe36cd75be0] decode_slice_header error
    
[h264 @ 0x7fe36cd75be0] no frame!
    
[h264 @ 0x7fe36ccc9080] Width/height changing with threads is not implemented. Update your Libav version to the newest one from Git. If the problem still occurs, it means that your file has a feature which has not been implemented.

    which clearly shows that my encoded frames do not match the original ones. I've been browsing the source code and can't seem to find a way of doing this. What I have currently (besides not working), involves a lot of guesswork, so even if I could make it work with the handful of example files I have, I would be scared to deploy this in production servers.

    So the obvious question is : Is there a safe, formal way of doing this ?

    Thanks in Advance

  • Revision 610e258cc5 : Make the round() replacement match C99 and POSIX. http://pubs.opengroup.org/onl

    8 août 2015, par Alex Converse

    Changed Paths :
     Modify /vp9/common/vp9_systemdependent.h



    Make the round() replacement match C99 and POSIX.

    http://pubs.opengroup.org/onlinepubs/009695399/functions/round.html

    Change-Id : Idf387d944d36bf593f8797db9053e11e5c9b9b39

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