diff --git a/modules/gallery/helpers/legal_file.php b/modules/gallery/helpers/legal_file.php
index 2cb0fb25..68403fa6 100644
--- a/modules/gallery/helpers/legal_file.php
+++ b/modules/gallery/helpers/legal_file.php
@@ -31,7 +31,7 @@ class legal_file_Core {
 
   static function get_filters() {
     $filters = array();
-    foreach (self::get_extensions() as $extension) {
+    foreach (legal_file::get_extensions() as $extension) {
       array_push($filters, "*." . $extension, "*." . strtoupper($extension));
     }
     return $filters;