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  • Mise à jour de la version 0.1 vers 0.2

    24 juin 2013, par

    Explications des différents changements notables lors du passage de la version 0.1 de MediaSPIP à la version 0.3. Quelles sont les nouveautés
    Au niveau des dépendances logicielles Utilisation des dernières versions de FFMpeg (>= v1.2.1) ; Installation des dépendances pour Smush ; Installation de MediaInfo et FFprobe pour la récupération des métadonnées ; On n’utilise plus ffmpeg2theora ; On n’installe plus flvtool2 au profit de flvtool++ ; On n’installe plus ffmpeg-php qui n’est plus maintenu au (...)

  • Personnaliser en ajoutant son logo, sa bannière ou son image de fond

    5 septembre 2013, par

    Certains thèmes prennent en compte trois éléments de personnalisation : l’ajout d’un logo ; l’ajout d’une bannière l’ajout d’une image de fond ;

  • Ecrire une actualité

    21 juin 2013, par

    Présentez les changements dans votre MédiaSPIP ou les actualités de vos projets sur votre MédiaSPIP grâce à la rubrique actualités.
    Dans le thème par défaut spipeo de MédiaSPIP, les actualités sont affichées en bas de la page principale sous les éditoriaux.
    Vous pouvez personnaliser le formulaire de création d’une actualité.
    Formulaire de création d’une actualité Dans le cas d’un document de type actualité, les champs proposés par défaut sont : Date de publication ( personnaliser la date de publication ) (...)

Sur d’autres sites (11510)

  • Trouble getting HTML5 vidio to play, in Firefox 33

    16 janvier 2015, par Randy

    I’m preparing to update some old pages to HTML5, and was surprised to see that it worked in Chrome, but not the latest Firefox (v.33.1... also tried v.32). What is odd is this... In Firefox it actually WILL play IF you "coax it". If you move the video position slider to someplace beyond the start (about 5 seconds in) and THEN click play, all is well. Further inspection showed that when I click play, the file pointer was jumping to the end of the file leaving my "poster" photo intact, leading the viewer to think there is nothing else they can do. If, however, you manually move the pointer back to anyplace beyond the first couple of seconds of the file (really !), and THEN click the PLAY button, FF will play the rest of the video fine.

    Sometimes i think that to the more technically minded among us, the universe doles out the weirder problems, while God laughs.

    I’d suspect video file corruption, but all my conversions were made with the very reliable ffmpeg utility, and tested with VLC. Again, it works fine from Chrome, which supposedly uses the same video format. Here’s a link...

    FF will play the older type ogv files, so if this is one of those things where FF, now at version 33 is at fault, I’ll have to detect the browser and write the order myself with a document.write(). But it would be nice to know if there is a more straigh forward solution.

    Note that I have tried adding the mime types to my HTACESS file. But the fact that the behavior is the same when point my browsers directly the file on my local machine, makles me doubt that is the problem.

    http://pixyland.org/peterpan/OurWedding2a.html

    And here is the page code

     



       

       







    <table align="center" border="1"><tr><td align="center">
    <div align="center">

    <video width="640" height="480" controls="controls" poster="Imagezz/Wedding/arIMG_2280.JPG">
    <source src="../vids/Arrival.mp4" type="video/mp4">  
    <source src="../vids/Arrival.webm" type="video/webm">
    <source src="../vids/Arrival.ogv" type="video/ogg">



    <p>If you are unable to view the video, here are some links to download <br />
     in a a few well supported video formats. You may be able to just download <br />
     and play one of these files without the browser.<br /><br />
     <strong>Download Video:</strong>nbsp;
       nbsp;<a href="http://stackoverflow.com/feeds/vids/Arrival.mp4">"MP4"</a>
       nbsp;<a href="http://stackoverflow.com/feeds/vids/Arrival.webm">"WEBM"</a>
       nbsp;<a href="http://stackoverflow.com/feeds/vids/Arrival.ogv">"Ogg"</a>
    </p>

    </source></source></source></video>
    </div>
    </td></tr></table>
  • Set the width of text in FFMPEG

    7 juin 2020, par Super Gadgets

    I am currently stuck with ffmpeg issue, I have an online video editor where users can add text and edit it.

    &#xA;&#xA;

    So I make an overlay div over the tag to let the user see exactly what the video will look like after render.

    &#xA;&#xA;

    But here is the issue : How can I get the css and let ffmpeg apply it on the text, the css will be the div where the transcription is how width, height , margins , colors ...

    &#xA;&#xA;

    Here is an example of a box :

    &#xA;&#xA;

    <div style="width:100px;text-align:center;top:10px;left:10px> TEXT HERE <div>&amp;#xA;

    &#xA ;&#xA ;

    P.s : I tried Aegisub, force_style but no options seems to offer setting the width of the box.

    &#xA ;&#xA ;

    Is there any way to do this ? Thank you.

    &#xA ;">

  • Reverse Engineering Radius VideoVision

    3 avril 2011, par Multimedia Mike — Reverse Engineering

    I was called upon to help reverse engineer an old video codec called VideoVision (FourCC : PGVV), ostensibly from a company named Radius. I’m not sure of the details exactly but I think a game developer has a bunch of original FMV data from an old game locked up in this format. The name of the codec sounded familiar. Indeed, we have had a sample in the repository since 2002. Alex B. did some wiki work on the codec some years ago. The wiki mentions that there existed a tool to transcode PGVV data into MJPEG-B data, which is already known and supported by FFmpeg.

    The Software
    My contacts were able to point me to some software, now safely archived in the PGVV samples directory. There is StudioPlayer2.6.2.sit.hqx which is supposed to be a QuickTime component for working with PGVV data. I can’t even remember how to deal with .sit or .hqx data. Then there is RadiusVVTranscoder101.zip which is the tool that transcodes to MJPEG-B.

    Disassembling for Reverse Engineering
    Since I could actually unpack the transcoder, I set my sights on that. Unpacking the archive sets up a directory structure for a component. There is a binary called RadiusVVTranscoder under RadiusVVTranscoder.component/Contents/MacOS/. Basic deadlisting disassembly is performed via ’otool’ as shown :

      otool -tV RadiusVVTranscoder | c++filt
    

    This results in a deadlisting of both PowerPC and 32-bit x86 code, as the binary is a "fat" Mac OS X binary designed to run on both architectures. The command line also demangles C++ function signatures which gives useful insight into the parameters passed to a function.

    Pretty Pictures
    The binary had a lot of descriptive symbols. As a basis for reverse engineering, I constructed call graphs using these symbols. Here are the 2 most relevant portions (click for larger images).

    The codec initialization generates Huffman tables relevant to the codec :



    The main decode function calls AddMJPGFrame which apparently does the heavy lifting for the transcode process :



    Based on this tree, I’m guessing that luma blocks can be losslessly transcoded (perhaps with different Huffman tables) which chroma blocks may rely on a different quantization method.

    Assembly Constructs
    I started looking at the instructions (the x86 ones, of course). The binary uses a calling convention I haven’t seen before, at least not for the x86 : Rather than pushing function arguments onto the stack, the code manually subtracts, e.g., 12 from the ESP register, loads 3 32-bit arguments into memory relative to ESP, and then proceeds with the function call.

    I’m also a little unclear on constructs such as "call ___i686.get_pc_thunk.bx" seen throughout relevant functions such as MakeRadiusQuantizationTables().

    I’m just presenting what I have so far in case anyone else wants to try their hand.

  • Boussole SPIP

    SPIP.net-La documentation officielle et téléchargement de (...) SPIP Code-La documentation du code de SPIP Programmer SPIP-La documentation pour développer avec (...) Traduire SPIP-Espace de traduction de SPIP et de ses (...) Plugins SPIP-L'annuaire des plugins SPIP SPIP-Contrib-L'espace des contributions à SPIP Forge SPIP-L'espace de développement de SPIP et de ses (...) Discuter sur SPIP-Les nouveaux forums de la communauté (...) SPIP Party-L'agenda des apéros et autres rencontres (...) Médias SPIP-La médiathèque de SPIP SPIP Syntaxe-Tester l'édition de texte dans SPIP