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  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • Personnaliser les catégories

    21 juin 2013, par

    Formulaire de création d’une catégorie
    Pour ceux qui connaissent bien SPIP, une catégorie peut être assimilée à une rubrique.
    Dans le cas d’un document de type catégorie, les champs proposés par défaut sont : Texte
    On peut modifier ce formulaire dans la partie :
    Administration > Configuration des masques de formulaire.
    Dans le cas d’un document de type média, les champs non affichés par défaut sont : Descriptif rapide
    Par ailleurs, c’est dans cette partie configuration qu’on peut indiquer le (...)

  • 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 (...)

Sur d’autres sites (11145)

  • Jerky Video from Jpgs encoded with ffmpeg [closed]

    16 février 2012, par Glstunna

    I have a bunch of jpg snapshots taken from a 3d program at perfect time frames.
    But when I have the videos compiled/encoded into a video by ffmpeg, I notice an annoying jerkiness. The jerkiness is not that pronounced, but enough to be annoying, especially during slow camera pans.

    This is what I use :

    "ffmpeg-lgpl.exe" -y  -r 29.97 -i "C:\vidsnaps\vid_%d.jpg" -b 8000k "C:\Users\peki.ICE\Documents\macbattle.mpg"

    I chose mpg (mpeg1video) because that is the format readily available in all end-user systems like XP without downloading extra codecs. The video images are guaranteed to match that framerate 29.97 as the camera in the 3d program pretty much waits for each frame to be dumped to file before moving to the next one.

    What other fancy ffmpeg flags do I have to set for this thing to stop being jerky.

    EDIT : see video example here and notice the light jerk/stuttering.
    http://www.youtube.com/watch?v=g-slsJBZA2w&feature=youtu.be

  • YouTube's HD Video Streaming Server Technology ?

    30 septembre 2013, par bgentry

    Lately I've been researching different methods for streaming MP4s to the browser. Flash Media Server is an obvious choice here (using Cloudfront), and most solutions I've seen use the RTMP protocol.

    However, I spent some time on YouTube with Firebug and Chrome debugger figuring out how their streaming worked and I discovered some interesting differences between some of their videos and quality rates.

    My two sample videos are A and B. A is available up to 480p and B is available up to 1080p. For both videos, all rates up to 480p are served in an FLV container with H.264 video and AAC audio, over HTTP. What's interesting here is that if you have not yet downloaded (cached) the entire video, and you try to skip forward to an uncached part of the video, a new request will be made with a 'begin' parameter equal to the target offset in milliseconds. Example from Video A at 480p :

    http://v11.lscache8.c.youtube.com/videoplayback?ip=0.0.0.0&sparams=id%2Cexpire%2Cip%2Cipbits%2Citag%2Calgorithm%2Cburst%2Cfactor%2Coc%3AU0dWTldQVF9FSkNNNl9PSlhJ&fexp=904806%2C902906%2C903711&algorithm=throttle-factor&itag=35&ipbits=0&burst=40&sver=3&expire=1279756800&key=yt1&signature=D2D704D63C242CF187CAA5B5D5BAFB8DFACAC5FF.39180C01559C976717B651A7EB1D0C6249231EB7&factor=1.25&id=8568eb3135971f6f&begin=111863
    

    
Response Headers:
    
Cache-Control:public,max-age=23472
    
Connection:close
    
Content-Length:14320637
    
Content-Type:video/x-flv
    
Date:Wed, 21 Jul 2010 17:23:48 GMT
    
Expires:Wed, 21 Jul 2010 23:55:00 GMT
    
Last-Modified:Wed, 19 May 2010 12:31:41 GMT
    
Server:gvs 1.0
    
X-Content-Type-Options:nosniff

    The file returned by this URL is a fully valid FLV containing only the portion of the video after the requested offset.

    I did the same kind of test on the higher resolution versions of Video B. At 720p and 1080p, YouTube will return a video in an MP4 container, also with H.264 video and AAC audio. What's impressive to me is that their server takes the same type of offset for an MP4 video (via the 'begin' parameter) and returns a valid, streamable MP4 (moov atom at the front of the file with correct offsets) that also only includes the requested portion of the video.

    So, how does YouTube do this ? How do they generate the FLV or MP4 container on the fly with the correct headers and only the desired segment of the requested video ? I know this can be accomplished using FFMPEG to seek to the desired start point and the qt-faststart script to reposition the moov atom to the front of the stream, but it seems like this would be too slow to handle on-demand for millions of YouTube viewers.

    Ideas ?

    Thanks in advance !

    Footnote : I am not allowed to include more than 1 link at this point, so here is Video A's URL : http:// www.youtube .com/watch ?v=hWjrMTWXH28 "Video available up to 480p"

  • Error converting youtube video to gif using npm

    15 décembre 2015, par user5663488

    I have installed ffmpeg and node.js. Trying to convert youtube video to gif images. In command prompt I have used "youtube-to-gif -u https://www.youtube.com/watch?v=NqxSgp385N0 -b 30 -d 5" command. Its showing error "Cannot find ffmpeg". Please suggest.

    This image displays the error while using the above command

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