diff --git a/Resources/public/js/largefile.js b/Resources/public/js/largefile.js
index 71f621e..b6cc698 100644
--- a/Resources/public/js/largefile.js
+++ b/Resources/public/js/largefile.js
@@ -110,7 +110,10 @@ var LargeFile = (function() {
             var container = document.getElementById(
                 inputField.getAttribute('data-previewcontainer')
             );
-            container.src = '/' + url;
+            if (url.substring(0,1) !== '/') {
+                url = '/' + url;
+            }
+            container.src = url;
 
             if (container.load) {
                 container.load();