diff --git a/ting_covers.pages.inc b/ting_covers.pages.inc
index 109acb9..728904a 100644
--- a/ting_covers.pages.inc
+++ b/ting_covers.pages.inc
@@ -8,12 +8,19 @@
 /**
  * Return the URL for the cover of an object.
  */
-function ting_covers_objects() {
+function ting_covers_objects($http_request = TRUE, $cover_data = array()) {
   $covers = array();
   $image_styles = array();
   $missing_images_local_ids = array();
 
-  foreach ($_POST['coverData'] as $cover_info) {
+  if ($http_request) {
+    $cover_data = $_POST['coverData'];
+  }
+  elseif (!$http_request && empty($cover_data)) {
+    return $covers;
+  }
+
+  foreach ($cover_data as $cover_info) {
     // Determine if the local id is a known negative.
     if (cache_get('ting_covers:' . $cover_info['local_id'], FALSE)) {
       break;
@@ -81,7 +88,12 @@ function ting_covers_objects() {
   }
 
   // Return all image information.
-  drupal_json_output($covers);
+  if ($http_request) {
+    drupal_json_output($covers);
+  }
+  else {
+    return $covers;
+  }
 }
 
 /**