diff --git a/src/image_reader.cpp b/src/image_reader.cpp
index df876ff8f..e3e708b31 100644
--- a/src/image_reader.cpp
+++ b/src/image_reader.cpp
@@ -84,7 +84,10 @@ image_reader* get_image_reader(std::string const& filename)
     {
         return factory<image_reader,std::string,std::string const&>::instance().create_object(*type,filename);
     }
-    return 0;
+    else
+    {
+        throw image_reader_exception("image_reader: can't determine type from input data");
+    }
 }
 
 }