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  • Installation en mode ferme

    4 février 2011, par

    Le mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
    C’est la méthode que nous utilisons sur cette même plateforme.
    L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
    Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...)

  • Emballe médias : à quoi cela sert ?

    4 février 2011, par

    Ce plugin vise à gérer des sites de mise en ligne de documents de tous types.
    Il crée des "médias", à savoir : un "média" est un article au sens SPIP créé automatiquement lors du téléversement d’un document qu’il soit audio, vidéo, image ou textuel ; un seul document ne peut être lié à un article dit "média" ;

  • Ajouter notes et légendes aux images

    7 février 2011, par

    Pour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
    Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
    Modification lors de l’ajout d’un média
    Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...)

Sur d’autres sites (6261)

  • 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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