Iframe Embed Shortcode

// Add Shortcode
function nsm_embed( $atts , $content = null ) {

	// Attributes
	extract( shortcode_atts(
		array(
			'title' => '',
			'alt' => '',
		), $atts )
	);

	// Code
        $title = $atts['title'];
        $alt = $atts['alt'];
        return str_replace('<iframe', '<iframe title="'. $title .'" alt="'. $alt .'"');
}
add_shortcode( 'embed', 'nsm_embed' );