Recherche avancée

Médias (1)

Mot : - Tags -/musée

Autres articles (103)

  • 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 (...)

  • 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 (...)

  • 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 (...)

Sur d’autres sites (6437)

  • FFMPEG dropping frames due to color space mismatch

    14 mai 2021, par Ismir Egal

    I've got two png image sequences with 30 frames each i'm trying to blend together.
The problem is that some of the images are in the rgb24 color space while some are in rgba.
Blending the two 30-frame animations together causes it to loose frames - the output is only 26 frames long and the two individual strips out-of-synch.

    


    Command used :

    


    ffmpeg -i a_%04d.png -i b_%04d.png -c:v libvpx -crf 4 -b:v 20M -filter_complex "blend=average" ab.webm


    


    Result :

    


    Input #0, image2, from 'a_%04d.png':
Duration: 00:00:01.20, start: 0.000000, bitrate: N/A
Stream #0:0: Video: png, rgb24(pc), 1280x720 [SAR 2835:2835 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
Input #1, image2, from 'b_%04d.png':
Duration: 00:00:01.20, start: 0.000000, bitrate: N/A
Stream #1:0: Video: png, rgb24(pc), 1280x720 [SAR 2835:2835 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
[...]
Input stream #0:0 frame changed from size:1280x720 fmt:rgb24 to size:1280x720 fmt:rgba
Input stream #1:0 frame changed from size:1280x720 fmt:rgb24 to size:1280x720 fmt:rgba
Input stream #0:0 frame changed from size:1280x720 fmt:rgba to size:1280x720 fmt:rgb24
Input stream #1:0 frame changed from size:1280x720 fmt:rgba to size:1280x720 fmt:rgb24
Input stream #0:0 frame changed from size:1280x720 fmt:rgb24 to size:1280x720 fmt:rgba
Input stream #1:0 frame changed from size:1280x720 fmt:rgb24 to size:1280x720 fmt:rgba
Input stream #0:0 frame changed from size:1280x720 fmt:rgba to size:1280x720 fmt:rgb24
Input stream #1:0 frame changed from size:1280x720 fmt:rgba to size:1280x720 fmt:rgb24
frame=26 fps=13 q=0.0 Lsize=942kB time=00:00:01.12 bitrate=6886.5kbits/s
video:941kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.072036%


    


    Creating videos from the individual sequences does not create this problem, it only occurs when blending them together.
    
Any idea how i can solve this problem or convert both inputs to the rgb24 format first (if that would help) ?

    


  • avcodec/mqc : Hardcode tables to save space

    7 mai 2021, par Andreas Rheinhardt
    avcodec/mqc : Hardcode tables to save space
    

    mqc currently initializes three arrays at runtime ; each of them
    has 2 * 47 elements, one is uint16_t, two are uint8_t, so that their
    combined size is 8 * 47. The source data for these initializations
    is contained in an array of 47 elements of size six. Said array is
    only used in order to initialize the other arrays, so the savings
    are just 2 * 47B. Yet this is dwarfed by the size of the code for
    performing the initializations : It is 109B (GCC 10.2, x64, -O3 albeit
    in an av_cold function) ; this does not even include the size of the
    code in the callers. So just hardcode these tables.

    This also fixes a data race, because the encoder always initialized
    these tables during init, although they might already be used at the
    same time by already running encoder/decoder instances.

    Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

    • [DH] libavcodec/j2kenc.c
    • [DH] libavcodec/jpeg2000dec.c
    • [DH] libavcodec/mqc.c
    • [DH] libavcodec/mqc.h
  • avcodec/speedhqenc : Hardcode table to save space

    10 décembre 2020, par Andreas Rheinhardt
    avcodec/speedhqenc : Hardcode table to save space
    

    The SpeedHQ encoder currently reverses the entries of two small tables
    and stores them in other tables. These other tables have a size of 48
    bytes, yet the code for their initialization takes 135 bytes (GCC 9.3,
    x64, O3 albeit in an av_cold function). So remove the runtime
    initialization and hardcode the tables.

    Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

    • [DH] libavcodec/speedhqenc.c