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  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Creating farms of unique websites

    13 avril 2011, par

    MediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
    This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...)

  • Les tâches Cron régulières de la ferme

    1er décembre 2010, par

    La gestion de la ferme passe par l’exécution à intervalle régulier de plusieurs tâches répétitives dites Cron.
    Le super Cron (gestion_mutu_super_cron)
    Cette tâche, planifiée chaque minute, a pour simple effet d’appeler le Cron de l’ensemble des instances de la mutualisation régulièrement. Couplée avec un Cron système sur le site central de la mutualisation, cela permet de simplement générer des visites régulières sur les différents sites et éviter que les tâches des sites peu visités soient trop (...)

Sur d’autres sites (10099)

  • Add a compat stdatomic.h implementation based on windows atomics

    17 juillet 2016, par Anton Khirnov
    Add a compat stdatomic.h implementation based on windows atomics

    Adapted from the code by Rémi Denis-Courmont from VLC
    • [DBH] compat/atomics/win32/stdatomic.h
    • [DBH] configure

  • FFmpeg for marking time video based on a reference date

    3 août 2016, par Denio Mariz

    I am trying to mark a timestamp in a video using Drawtext filter.
    FFmpeg easily marks timestamps based on localtime, gmtime or even PTS. However, I want to assign a reference time (start time) for the timestamp in order to represent the time the video was recorded (not encoded).

    Reading the documentation, I found that option "basetime" can be used for this purpose. However it seems that is not working or I am missing something.

    The command line I am using is :

    ffmpeg -y -i input.mp4 -filter_complex drawtext="fontfile=/tmp/UbuntuMono-B.ttf: fontsize=36: fontcolor=yellow: box=1: boxcolor=black@0.4: text='Wall Clock Time\: %{gmtime\:%Y-%m-%d %T}': basetime=1456007118" output.mp4

    By using basetime=1456007118", it was expected the start time was set to ’02/20/2016 20:25:18’ since 1456007118 is the UTC time for that time and date :

    date -d '02/20/2016 20:25:18' +"%s" # format MM/DD/AAAA hh:mm:ss
    
1456007118

    However, no error is issued by FFMpeg and the video is marked with current GMT, ignoring "basetime" option.

    Any hint ?
    Thanks.

    Complete information about FFmpeg version and output is :

       ffmpeg -y -i /home/denio/Videos/Interstellar_2014_Trailer_4_5.1-1080p-HDTN.mp4 -filter_complex drawtext="fontfile=/tmp/UbuntuMono-B.ttf: fontsize=36: fontcolor=yellow: box=1: boxcolor=black@0.4: text='Wall Clock Time\: %{gmtime\:%Y-%m-%d %T}': basetime=1470226363" /tmp/x.mp4
       ffmpeg version 3.1.1 Copyright (c) 2000-2016 the FFmpeg developers
         built with gcc 5.3.1 (Ubuntu 5.3.1-14ubuntu2.1) 20160413
         configuration: --enable-libxavs --enable-bzlib --enable-libfaac --enable-libfreetype --enable-libfontconfig --enable-libmp3lame --enable-libschroedinger --enable-libspeex --enable-libvorbis --enable-libx264 --enable-libx265 --enable-libxvid --enable-zlib --enable-x11grab --enable-static --enable-pthreads --enable-gpl --enable-nonfree --enable-version3 --disable-ffserver --enable-libgsm --enable-librtmp --enable-libvpx --enable-libschroedinger --enable-libopencore-amrnb --enable-libopenjpeg
         libavutil      55. 28.100 / 55. 28.100
         libavcodec     57. 48.101 / 57. 48.101
         libavformat    57. 41.100 / 57. 41.100
         libavdevice    57.  0.101 / 57.  0.101
         libavfilter     6. 47.100 /  6. 47.100
         libswscale      4.  1.100 /  4.  1.100
         libswresample   2.  1.100 /  2.  1.100
         libpostproc    54.  0.100 / 54.  0.100
       ...
       ...

  • Revision 903801f1ef : vp9 decoder : row-based multi-threaded loopfilter Implemented parallel loopfilte

    28 décembre 2013, par Yunqing Wang

    Changed Paths :
     Modify /vp9/common/vp9_loopfilter.c


     Modify /vp9/common/vp9_loopfilter.h


     Modify /vp9/decoder/vp9_decodeframe.c


     Add /vp9/decoder/vp9_dthread.c


     Add /vp9/decoder/vp9_dthread.h


     Modify /vp9/decoder/vp9_onyxd_if.c


     Modify /vp9/decoder/vp9_onyxd_int.h


     Modify /vp9/decoder/vp9_thread.c


     Modify /vp9/decoder/vp9_thread.h


     Modify /vp9/vp9dx.mk



    vp9 decoder : row-based multi-threaded loopfilter

    Implemented parallel loopfiltering, which uses existing tile-
    decoding threads. Each thread works on one row, and when that row
    is loopfiltered, it moves to next unattended row. To ensure the
    correct filtering order, threads are synchronized and one
    superblock is filtered only if the superblocks it depends on are
    filtered already.

    To reduce synchronization overhead and speed up the decoder, we use
    nsync > 1 for high resolution.

    Performance tests :
    1. on desktop :
    8-tile 4k video using 8 threads, speedup : 70% - 80%
    4-tile HD video using 4 threads, speedup : 35%
    2. on mobile device(Nexus 7) :
    4-tile 1080p video using 4 threads, speedup : 18% - 25%
    4-tile 1080p video using 2 threads, speedup : 10% - 15%

    Change-Id : If54b4a11960dd706c22d5ad145ad94156031f36a

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