gistfile1.php

<?php

$wgExtensionFunctions[] = 'efVideoSetUp';

function videoCreateAttrs($args) {
    $attrs = array();
    foreach($args as $key => $value) {
        $attrs[] = sprintf('%s="%s"', $key, htmlspecialchars($value));
    }
    return implode(" ", $attrs);
}

function efVideoSetUp() {
    global $wgParser;
    $wgParser->setHook('video', 'efVideoRender');
    $wgParser->setHook('source', 'efSourceRender');
    return true;
}

function efVideoRender($input, $args, $parser, $frame) {
    $output = $parser->recursiveTagParse($input, $frame);
    return "<video " . videoCreateAttrs($args) . ">$output</video>";
}                    
                     
function efSourceRender($input, $args, $parser, $frame) {
    return "<source " . videoCreateAttrs($args) . "/>";
}