diff --git a/src/wand/magick.rs b/src/wand/magick.rs
index 8475bc5..c298824 100644
--- a/src/wand/magick.rs
+++ b/src/wand/magick.rs
@@ -251,6 +251,8 @@ impl MagickWand {
         }
     }
 
+    // Level an image. Black and white points are multiplied with QuantumRange to
+    // decrease dependencies on the end user.
     pub fn level_image(
         &self,
         black_point: f64,