diff --git a/Model/Resizer.php b/Model/Resizer.php
index 5a966f5..42b2e48 100644
--- a/Model/Resizer.php
+++ b/Model/Resizer.php
@@ -315,6 +315,9 @@ protected function isAnimatedGif($file)
         $filepointer = null;
 
         if (is_string($file)) {
+            if (strpos(strtolower($file), '.gif') === false) {
+                return false;
+            }
             $filepointer = fopen($file, "rb");
         } else {
             $filepointer = $file;
@@ -344,4 +347,4 @@ protected function isAnimatedGif($file)
         return $frames > 1;
     }
 
-}
\ No newline at end of file
+}