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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 (...)

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  • Poor video quality in first few frames using video output options in gganimate

    27 janvier 2021, par Nautica

    I'm trying to export some animations I've made using gganimate through video format as the gifs I'm creating are quite large.

    


    Sample code :

    


    library(gganimate)

p <- ggplot(mtcars, aes(factor(cyl), mpg)) +
  theme_dark() +
  theme(panel.grid = element_line(colour = "white")) +
  geom_boxplot() +
  transition_states(
    gear,
    transition_length = 2,
    state_length = 1
  ) +
  enter_fade() +
  exit_shrink() +
  ease_aes('sine-in-out')

anim_save("example.mp4",
          animate(
            p,
            nframes = 450,
            fps = 25,
            width = 1280,
            height = 720,
            type = "cairo",
            start_pause = 50,
            end_pause = 50,
            renderer = av_renderer()
          ))


    


    Produces the video seen here : https://vimeo.com/505019987

    


    With the standard ggplot2 theme : https://vimeo.com/505020822

    


    This is another example of something I made using gganimate : https://www.youtube.com/watch?v=fHzjl_z_sSo

    


    You can see that the video quality in the first few frames are very bad. In the video with the standard ggplot2 theme and the YouTube video, the gridlines and watermark text are not visible at the start but fade in much later. I don't know much about video codecs but I assume it has something to do with the ffmpeg library the av package/av_renderer() is using. Has anyone experienced something like this ?

    


  • Looking for video libraries for editing video on windows/ios/azure service [on hold]

    17 juillet 2015, par sanyam

    Which library would be a good bet in terms of ...
    1. Richness in features (I want to create a video from short clips and images with effects and filters). Think auto videos created from Google Photos.
    2. Extensibility - I would prefer using similar tech on IOS and Windows apps. Might have to offload some processing to a web service on Azure (windows or linux).
    3. Programmability - An API is preferred over command line as it gives more flexibility and better error handling.

    Given all these options, what is my best bet ? I’ve only looked at ffmpeg till now, is there a better alternative ?

  • ffmpeg copy video in video with a specific time

    13 février 2017, par Alkl

    Im new in this topic (beginner) and Im german... So it’s a bit difficult to find the correct words...

    I’ll try to explain what I’ve done and what I want to do :

    1. Extract video area from the original video converted in PRORES codec :

      ffmpeg.exe -i test.mkv -ss 00:06:21.99 -t 00:00:01.94 -async 1 -strict -2 -c:v prores_ks -pix_fmt yuva444p10le -profile:v 4444 -bits_per_mb 8000 -s 1920x1080 cut_video.mov

    2. Edit the cut in After Effects

    3. Convert the PRORES in Matroska

      ffmpeg.exe -i "C :\Users\Alex\Desktop\ffmpeg-20170202-08b0981-win64-static\bin\cut_video\cut_video.mov" -vcodec ffv1 -acodec pcm_s16le temp.mkv

    4. Replace the video area in the originale video file at the time 00:06:21.99...

    I spend 4 hours for the two commands...
    So I despair at the fourth step. Is it possible ? Can you help me ?

    I made a picture, so you can understand better what Im doing... : http://i.imgur.com/HqlNxzW.jpg

    Best regards from germany,

    Alex