diff --git a/QuickLook/Helpers/WindowHelper.cs b/QuickLook/Helpers/WindowHelper.cs
index 5cc4664..cbe342c 100644
--- a/QuickLook/Helpers/WindowHelper.cs
+++ b/QuickLook/Helpers/WindowHelper.cs
@@ -80,8 +80,8 @@ namespace QuickLook.Helpers
                     matrix = src.CompositionTarget.TransformToDevice;
                 }
 
-            pixelX = (int) (matrix.M11 * unitX);
-            pixelY = (int) (matrix.M22 * unitY);
+            pixelX = (int)Math.Round((matrix.M11 * unitX));
+            pixelY = (int)Math.Round((matrix.M22 * unitY));
         }
 
         internal static bool IsForegroundWindowBelongToSelf()
@@ -149,4 +149,4 @@ namespace QuickLook.Helpers
             }
         }
     }
-}
\ No newline at end of file
+}