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  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

  • Le profil des utilisateurs

    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

  • Configurer la prise en compte des langues

    15 novembre 2010, par

    Accéder à la configuration et ajouter des langues prises en compte
    Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
    De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
    Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...)

Sur d’autres sites (11858)

  • intrax8 : Have function signature match across declaration and definition

    20 septembre 2016, par Diego Biurrun
    intrax8 : Have function signature match across declaration and definition

    libavcodec/intrax8.c(776) : warning C4028 : formal parameter 1 different from declaration
    • [DBH] libavcodec/intrax8.c

  • Use ffmpeg to match an image to source frames in video [closed]

    25 mai 2024, par user22335954

    I'm trying to write an application to split a single video into multiple pieces based on the appearance of a specific image. (Think title cards). I have video files that may have more than one episode or content inside of a single file and I want them split anywhere I find that title card or image.

    


    My application works by the user providing a timestamp in the format of 00:00:00 to specify the title card image which is then used like this :

    


    ffmpeg -i FILE -qmin 1 -qscale:v 1 -vframes 00:00:00 -f image2 img.png


    


    Now I want to compare that image (img.png) to the source video file using the following example command I've found :

    


    ffmpeg -i FILE -loop 1 -i img.png -an -filter_complex "blend=difference:shortest=1,blackframe=90:20" -f null


    


    I've had to play around with the blackframe=90:20 values to get what I think are correct matches, but I don't understand what these values and/or the blackframe filter is actually controlling. The blend documentation : https://ffmpeg.org/ffmpeg-filters.html#Examples-46 doesn't seem to go into much detail about what is actually happening. I do understand the difference blend means I'm essentially looking for the smallest difference, indicating a frame match to my img, but beyond that I'm sort of just guessing.

    


    Additionally, the output shows a bunch of :

    


    [Parsed_blackframe_1 @ 0x5c1183081880] frame:195 pblack:99 pts:6506 t:6.506000 type:B last_keyframe:135


    


    Based on the frames I can parse those out to find the non-sequential frames and find how how many segments I expect in the video, but when I go to split them, I don't know how to translate the frame or the t value into a timestamp format of 00:00:00. Even for matches that I'm 100% sure of, the frame values don't seem to line up with what I expect. For example, from watching the video, I know that a perfect match occurs at exactly 00:01:45, but the blackframe data says the match occurs at frame 1471 or t:49.08 (the video has a framerate of 29.97). 1471 / 29.97 is indeed 49.08, but that does not correlate to the actual time of 1:45 (105 seconds). How can I convert these values into timestamps (or just show the timestamps of the frames) ?

    


  • avcodec/nvenc : Make sure that enum and array index match

    28 septembre 2016, par Timo Rothenpieler
    avcodec/nvenc : Make sure that enum and array index match

    Based on libav commits by Luca Barbato and Yogender Gupta :
    
https://git.libav.org/?p=libav.git;a=commit;h=352741b5ead1543d775ccf6040f33023e4491186
    
https://git.libav.org/?p=libav.git;a=commit;h=e02e2515b24bfc37ede6ca1744696230be55e50b
    • [DH] libavcodec/nvenc.c

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