diff --git a/src/ImageSizer.php b/src/ImageSizer.php
index 5c3df37..ffe0269 100644
--- a/src/ImageSizer.php
+++ b/src/ImageSizer.php
@@ -32,6 +32,9 @@ class ImageSizer {
     if ($uri[0] === '/' && $uri[1] === '/') {
       $uri = 'http:' . $uri;
     }
+    if (strpos($uri, 'http') !== 0) {
+      return @getimagesize($uri);
+    }
 
     @static::$fastImage->load($uri);