HTML5 video shortcode for WordPress

video5.php

<?php
/**
 * Shortcode callback [video5 src="" width="" height=""]
 *
 *	@param array atts shortcode atts
 *	@return string HTML5 video tag
 */

add_shortcode( 'video5', function( $atts, $content = null ) {
	global $content_width;
	extract( shortcode_atts( array(
		"src" => '',
		"width" => '',
		"height" => '',
	), $atts ) );
	// Sanitize a bit
	$width = (int) $width !== 0 ? $width : $content_width;
	$height = (int) $height !== 0 ? $height : (int) ( $width / 16 ) * 9;
	// Validate the link and return the output
	if ( filter_var( $src, FILTER_VALIDATE_URL ) ) 
		return '<video src="'.$src.'" width="'.$width.'" height="'.$height.'" controls autobuffer>';
});