diff --git a/image.hpp b/image.hpp
index cfd0d7ef..63961e02 100644
--- a/image.hpp
+++ b/image.hpp
@@ -45,6 +45,7 @@ namespace util { namespace image {
 
         /// allocate and return a buffer with the same contents
         template <typename U = T> buffer<U> clone (void) const;
+        template <typename U> buffer<U> cast (void) const { return clone<U> (); }
 
         buffer<T> downsample (float factor) const;