Wordpress Featured Image in RSS Feed

wp_featured_image_feed.php

/* 
* @param - DEFAULTIMG - declared as global constant
* define("DEFAULTIMG", "/wp-content/themes/[theme-name]/public/images/[path-to-img.jpg]");
*
*/

// Add Featured image item to rss feed

function featuredtoRSS() {
  global $post;
  if ( has_post_thumbnail( $post->ID ) ){
    $thumb_id = get_post_thumbnail_id();
    $thumb_url_array = wp_get_attachment_image_src($thumb_id, 'large', true);
    $image = $thumb_url_array[0];
  } else {
        $image = '/wp-content/themes/angelfiremega/public/images/af-logo.jpg' ;
  } ?>
  <featuredimage><?php echo( $image ); ?></featuredimage>
<?php }

// Add featured image to feeds
add_action('rss_item','featuredtoRSS');
add_action('rss2_item','featuredtoRSS');
add_action('commentsrss2_item','featuredtoRSS');