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  • Gestion générale des documents

    13 mai 2011, par

    MédiaSPIP ne modifie jamais le document original mis en ligne.
    Pour chaque document mis en ligne il effectue deux opérations successives : la création d’une version supplémentaire qui peut être facilement consultée en ligne tout en laissant l’original téléchargeable dans le cas où le document original ne peut être lu dans un navigateur Internet ; la récupération des métadonnées du document original pour illustrer textuellement le fichier ;
    Les tableaux ci-dessous expliquent ce que peut faire MédiaSPIP (...)

  • 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 (...)

  • 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 (...)

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  • ffmpeg video replay with time-sync needs actual recording times

    16 juillet 2018, par navySV

    I am attempting to use ffmpeg to replay multiple video files time-synched, but the zero-based video start time is preventing this.

    I have ffmpeg commands to successfully capture a Microsoft Windows 7 desktop into a video file and replay it with a timestamp value (see below), but the internal timestamp is always starting near zero. How can ffmpeg display the actual time when the video was recorded (and not the time since the start of the video i.e. zero) ?

    For example, if the video started to be recorded at 10:47 am, the ffplay command should display a timestamp similar to "10:47:31" during playback (and not "00:00:31").

    video-capture command :

    ffmpeg -f gdigrab -offset_x 0 -offset_y 0 -video_size 1920x1080 -i desktop -c:v libx264 -preset medium -f mpegts -framerate 24 -y fileA.ts

    playback command :

    ffplay -vf "drawtext=fontfile=/windows/fonts/arial.ttf: text='%{pts\:gmtime\:0\:%H\\\:%M\\\:%S}':box=1:x=(w-tw)/2:y=h-(2*lh)" fileA.ts

    parameters I’ve tried unsuccessfully in the previous commands (including moving these around into different places in the commands) :

    -timestamp now
    

    
-vsync 0
    

    
-copyts

    (every attempt to use -copyts generates errors about "non-strictly-monotonic PTS" or "Non-monotonous DTS in output stream" no matter where I put this parameter)

    -filter_complex "[0:v] setpts=PTS"

    The ultimate goal is to capture four video files (recorded on four different computers and probably having different start times), and then to replay all four in time-sync (which is not possible using only the zero-based start times).

    For example, I’ve been successful at replaying four video files in a 2x2 arrangement, using the following command (I added the -ss parameter to demonstrate I can move the start time of the replay). Unfortunately, they always time-sync to the zero-based first video frame (so they all play from the beginning of the video file). I need the replay to be time-syncing to the actual recorded time for each video. If the four videos were captured starting at times 10:47:00, 10:47:51, 10:48:44, and 10:49:01, I want to be able to replay all of them so that all are displaying the same timestep at the same time (so if one video were displaying 10:48:33, all of the videos would be displaying the same time or a blank screen if that time was unavailable) .

    ffmpeg -ss 00:00:30 -i fileA.ts -i fileB.ts -i fileC.ts -i fileD.ts -filter_complex "[0:v][1:v]hstack[top];[2:v][3:v]hstack[bottom];[top][bottom]vstack[v]" -map "[v]" -timestamp now -f mpegts - | ./ffplay - -x 1920 -y 1080

    Ideally, I would also like to be able to use a real time value (something like "ffplay -ss 10:48:00 ...") to start the video replay at a different position, but worst-case I can write a script to do the needed conversion of the time value.

    My ffmpeg version is a Windows 7 64-bit static build "N-90810-g153e920892" on 2018Apr22 (downloaded from https://www.ffmpeg.org/download.html)

  • Revision 29928 : On réutilise l’ancien code pour débuter notre branche

    17 juillet 2009, par kent1@… — Log

    On réutilise l’ancien code pour débuter notre branche

  • avcodec : add D3D12VA hardware accelerated H264 decoding

    5 décembre 2023, par Wu Jianhua
    avcodec : add D3D12VA hardware accelerated H264 decoding

    The implementation is based on :
    
https://learn.microsoft.com/en-us/windows/win32/medfound/direct3d-12-video-overview
    

    With the Direct3D 12 video decoding support, we can render or process
    
the decoded images by the pixel shaders or compute shaders directly
    
without the extra copy overhead, which is beneficial especially if you
    
are trying to render or post-process a 4K or 8K video.
    

    The command below is how to enable d3d12va :
    
ffmpeg -hwaccel d3d12va -i input.mp4 output.mp4
    

    Signed-off-by : Wu Jianhua <toqsxw@outlook.com>
    
Signed-off-by : Tong Wu <tong1.wu@intel.com>
    • [DH] configure
    • [DH] libavcodec/Makefile
    • [DH] libavcodec/d3d11va.h
    • [DH] libavcodec/d3d12va_decode.c
    • [DH] libavcodec/d3d12va_decode.h
    • [DH] libavcodec/d3d12va_h264.c
    • [DH] libavcodec/dxva2.c
    • [DH] libavcodec/dxva2.h
    • [DH] libavcodec/dxva2_av1.c
    • [DH] libavcodec/dxva2_h264.c
    • [DH] libavcodec/dxva2_hevc.c
    • [DH] libavcodec/dxva2_internal.h
    • [DH] libavcodec/dxva2_mpeg2.c
    • [DH] libavcodec/dxva2_vc1.c
    • [DH] libavcodec/dxva2_vp9.c
    • [DH] libavcodec/h264_slice.c
    • [DH] libavcodec/h264dec.c
    • [DH] libavcodec/hwaccels.h
    • [DH] libavcodec/hwconfig.h

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