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  • MediaSPIP 0.1 Beta version

    25 avril 2011, par

    MediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
    The zip file provided here only contains the sources of MediaSPIP in its standalone version.
    To get a working installation, you must manually install all-software dependencies on the server.
    If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)

  • ANNEXE : Les plugins utilisés spécifiquement pour la ferme

    5 mars 2010, par

    Le site central/maître de la ferme a besoin d’utiliser plusieurs plugins supplémentaires vis à vis des canaux pour son bon fonctionnement. le plugin Gestion de la mutualisation ; le plugin inscription3 pour gérer les inscriptions et les demandes de création d’instance de mutualisation dès l’inscription des utilisateurs ; le plugin verifier qui fournit une API de vérification des champs (utilisé par inscription3) ; le plugin champs extras v2 nécessité par inscription3 (...)

  • Problèmes fréquents

    10 mars 2010, par

    PHP et safe_mode activé
    Une des principales sources de problèmes relève de la configuration de PHP et notamment de l’activation du safe_mode
    La solution consiterait à soit désactiver le safe_mode soit placer le script dans un répertoire accessible par apache pour le site

Sur d’autres sites (7053)

  • Anomalie #3075 : #LOGO_ARTICLE_RUBRIQUE_NORMAL ne retourne rien sous SPIP 3

    7 octobre 2018

    C’est juste que je déteste les comportements apparemment dérogatoires.

    Or, j’ai l’impression que _NORMAL et _SURVOL sont des suffixes qui permettent de ne retourner qu’un des 2 logos.
    Mais que ces suffixes ne marchent pas avec #LOGO_ARTICLE_RUBRIQUE

    Donc, oui, j’ai reçu une réponse qui met sur le même plan les suffixes _NORMAL/_SURVOL et _RUBRIQUE

    Mais puisque j’ai pu comprendre de travers par une systématisation abusive des suffixes en question (_NORMAL/_SURVOL), je penses qu’il faut, soit corriger le code (ce qui serait esthétiquement souhaitable), soit documenter la non généricité de ces suffixes (ce qui éviterait de passer à côté de l’info qui finalement n’est que dans le code).

    Et j’insiste qu’il n’est pas logique ni cohérent de ne pas pouvoir extraire le logo normal ou de survol dans toutes les situations.

  • How to set frame offset for source and reference video for calculating using FFMpeg commandline ?

    1er septembre 2018, par Souvik Das

    I have a scenario where I am streaming a reference video on a server machine and receiving it at a client machine with exact same codec, using FFMpeg via UDP/RTP.

    So, I have a reference.avi file and a recording.ts file with me. Now, due to a network side issue and FFMpeg discarding old frames, often the recording.ts lacks exactly 12 FRAMES from the beginning. Sometimes, it may lack more frames in-between but that’d due to general network traffic and packet loss reason and I don’t plan to account for that. Anyways, due to those 12 frames, when I calculate the PSNR, it drops down to 13, even though remaining frames may/may not be affected.

    So, my aim is to discard first 12 frames from reference.ts and then compare. For that, I would also need to adjust the frames from recording.ts.

    Consider the following scenario :

    reference.ts has 1500 frames. So naturally I am going to cut-short it 1488. Then we have the following cases :

    1. recording.ts has 1500 frames. This is not affected. Still I will remove 12 frames to match the count. So frame 1 would then represent frame 13.
    2. recording.ts has 1496 frames. This is not affected. Still I will remove 12 frames even though it’d get to 1484 count assuming that frame 1 would then represent frame 13.
    3. recording.ts has 1488 frames. This is affected. No need to remove frames.
    4. recording.ts has 1480 frames. This is affected. No need to remove frames.

    Once that is done, then I will calcualte the PSNR. So, my FFMpeg should be able to do all this, hopefully in a single command on bash.

    A better alternative would be for FFMpeg to find the where the 13th frame is in recording.ts and then cut-short from the beginning. That’d be more preferred and even more if there is no cut-shorting required, i.e. if offset could be set in-line to command and no additional video output is generated for use in PSNR comparison.

    Current I am using the following command to calculate the PSNR.

    ffmpeg -i 'recording.ts' -vf "movie='reference.avi', psnr=stats_file='psnr.txt'" -f rawvideo -y /dev/null

    It’d be great if somebody could help me in this regard. Thanks.

  • OpenCV video capture - output even potentially corrupt frames

    20 juillet 2018, par J. S.

    In FFmpeg, there is a flag "output_corrupt" that allows the command to output even corrupted frames. I am sending h264 stream to a server where its first few frames are corrupted. By setting "output_corrupt" flag in my FFmpeg command, I am able to view the live stream.
    I can see the live stream by piping FFmpeg data to OpenCV VideoCapture (i.e. cv2.VideoCapture(’/dev/stdin’))

    Note : since my plan is to run CV algorithms on those frames, I need to be able to run it on OpenCV.

    However, by not directly sending the data through VideoCapture, it unavoidably causes some latency issue.

    The best scenario would be to just directly send the h264 stream to OpenCV VideoCapture (i.e. cv2.VideoCapture(’udp ://......’))
    However, because of the corrupted frames, the OpenCV script gets stuck after a second.

    Is there any way to run OpenCV VideoCapture such that it still outputs potentially corrupt frames ?

    Thank you.

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