diff --git a/lib/fastimage/fastimage.rb b/lib/fastimage/fastimage.rb
index 88faae7..41c4a2c 100644
--- a/lib/fastimage/fastimage.rb
+++ b/lib/fastimage/fastimage.rb
@@ -415,7 +415,7 @@ class FastImage
 
   def fetch_using_base64(uri)
     decoded = begin
-      uri.split(',')[1].unpack1("m")
+      uri.split(',')[1].unpack("m").first
     rescue
       raise CannotParseImage
     end