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  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

  • 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 (...)

  • Participer à sa traduction

    10 avril 2011

    Vous pouvez nous aider à améliorer les locutions utilisées dans le logiciel ou à traduire celui-ci dans n’importe qu’elle nouvelle langue permettant sa diffusion à de nouvelles communautés linguistiques.
    Pour ce faire, on utilise l’interface de traduction de SPIP où l’ensemble des modules de langue de MediaSPIP sont à disposition. ll vous suffit de vous inscrire sur la liste de discussion des traducteurs pour demander plus d’informations.
    Actuellement MediaSPIP n’est disponible qu’en français et (...)

Sur d’autres sites (10604)

  • Revision 8c2e5e4964 : Merge "Correct 3 step search site initialziation"

    24 septembre 2013, par Yaowu Xu

    Merge "Correct 3 step search site initialziation"

  • Transcoding & displaying user-uploaded videos for cross-browser/platform compatibility

    5 avril 2012, par Jonathan Amend

    I want to display user-uploaded videos in high quality on different browsers/platforms. I think I have a pretty good start, but there are a few issues. I have at my disposal ffmpeg 0.10 (called from PHP) and jwPlayer 5.8 (licensed).

    Ideally I would like to support :

    • Browsers with Flash 9+
    • Modern Firefox/Chrome/Safari without Flash
    • iOS 4.1+
    • Android 2.2+

    My current transcoding commands are :

    $commands = array(
    
    'flv' => "/usr/bin/ffmpeg -y -i {$sourceFile} -b 500k -ar 22050 -ab 64 {$tmpFileName}.flv 2>&1",
    
    'webm' => "/usr/bin/ffmpeg -i {$sourceFile} -acodec libvorbis -ac 2 -ab 96k -ar 44100 -b 500k {$tmpFileName}.webm 2>&1",
    
    'mp4' => "/usr/bin/ffmpeg -i {$sourceFile} -acodec libfaac -ab 96k -vcodec libx264 -level 21 -refs 2 -vf 'scale=trunc(ih*a/2)*2:trunc(iw/a/2)*2' -b 500k -bt 1000k -threads 0 -f mp4 {$tmpFileName}.pre.mp4 2>&1",
    
    'jpg' => "/usr/bin/ffmpeg -y -i {$sourceFile} -ss 5 -vcodec mjpeg -vframes 1 -an -f rawvideo {$tmpFileName}.jpg 2>&1"
    
);
    

    
$fastStartCommand = "/usr/bin/qt-faststart {$tmpFileName}.pre.mp4 {$tmpFileName}.mp4");

    My current display code is this :

    <video controls="controls" width="{$width}" height="{$height}" poster="{$fileJPG}" style="width: {$width}px; height: {$height}px;">
    
    <source src="{$fileMP4}" type="video/mp4" data-ext="mp4"></source>
    
    <source src="{$fileWEBM}" type="video/webm" data-ext="webm"></source>
    
    <a href="http://stackoverflow.com/feeds/tag/{$fileMP4}" title="Play Video">
    
        <img border="0" src="http://stackoverflow.com/feeds/tag/{$fileJPG}" width='0' height='0' alt="Play Video" />
    
    </a>
    
</video>
    
<code class="echappe-js">&lt;script type=&quot;text/javascript&quot;&gt;<br />
    
swfobject.embedSWF(<br />
    
    &amp;#39;/flash/jwPlayer.swf&amp;#39;,<br />
    
    &amp;#39;video&amp;#39;,<br />
    
    {$width},<br />
    
    {$height},<br />
    
    &amp;#39;9.0.0&amp;#39;,<br />
    
    &amp;#39;&amp;#39;,<br />
    
    {<br />
    
        file: &amp;#39;{$fileFLV}&amp;#39;,<br />
    
        width: {$width},<br />
    
        height: {$height},<br />
    
        provider: &amp;#39;video&amp;#39;,<br />
    
        stretching: &amp;#39;uniform&amp;#39;,<br />
    
        smoothing: &amp;#39;true&amp;#39;,<br />
    
        dock: &amp;#39;true&amp;#39;<br />
    
    },<br />
    
    {<br />
    
        menu: &amp;#39;false&amp;#39;,<br />
    
        allowfullscreen: &amp;#39;true&amp;#39;,<br />
    
        allowscriptaccess: &amp;#39;always&amp;#39;,<br />
    
        allownetworking: &amp;#39;always&amp;#39;,<br />
    
        wmode: &amp;#39;transparent&amp;#39;<br />
    
    }<br />
    
);<br />
    
&lt;/script&gt;

    The idea is to prefer the Flash player (we have many custom skins that we would like to keep using), then fall back to HTML 5 video, and if that fails, show the JPEG with a link to the mp4 file (that seems to work as a last-ditch effort for iOS 2/3 and old browsers so they can at least play the video by launching QuickTime).

    The main issues that I'm not sure how to solve right now are :

    • How can I show a higher quality video in Flash ? I tried using the mp4 video instead of the flv but it doesn't work and I only get sound, no video. I think Flash is supposed to support h.264 these days, but how ? And do I have to use a different transcoding method for older and newer versions of Flash ?
    • How can I transcode the video with better quality ? Right now I am using the same bitrate for all resolutions. Any chance there is a way for ffmpeg to adjust the bitrate automatically ? Or can I detect and match the resolution of the uploaded video to a list of resolution -> bitrates somehow ?

  • H264 steganography : Step by step compression code/library

    16 septembre 2013, par user1960810

    I have an algorithm for steganography on h264 (AVC). But I am unable to find a library or equations for H264 compression. The steps are DCT-> Quantization-> Entropy encode**. Can anyone provide me the step by step compression code or equations for these steps ? The intention is to manipulate the LSBs after the entropy encoding step. I am using EmguCV and C# for my project. I am also using FFMpeg. I have a very little knowledge on C and C++.

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