diff --git a/image.hpp b/image.hpp
index 6e8e3eb6..713ea646 100644
--- a/image.hpp
+++ b/image.hpp
@@ -50,6 +50,8 @@ namespace util { namespace image {
 
         //---------------------------------------------------------------------
         constexpr size_t area (void) const;
+        constexpr extent2u extent (void) const;
+
         constexpr bool is_packed (void) const;
 
         size_t w;
diff --git a/image.ipp b/image.ipp
index 64cbb961..d8e6d60b 100644
--- a/image.ipp
+++ b/image.ipp
@@ -28,6 +28,16 @@ namespace util { namespace image {
         return w * h;
     }
 
+
+    //-------------------------------------------------------------------------
+    template <typename T>
+    constexpr extent2u
+    buffer<T>::extent (void) const
+    {
+        return { w, h };
+    }
+
+
     //-------------------------------------------------------------------------
     template <typename T>
     constexpr bool