diff --git a/wxPython/src/_image.i b/wxPython/src/_image.i
index 154f55d5e0..bcd1deb33d 100644
--- a/wxPython/src/_image.i
+++ b/wxPython/src/_image.i
@@ -329,8 +329,8 @@ MustHaveApp(ConvertToBitmap);
 MustHaveApp(ConvertToMonoBitmap);
 
     %extend {
-        wxBitmap ConvertToBitmap() {
-            wxBitmap bitmap(*self);
+        wxBitmap ConvertToBitmap(int depth=-1) {
+            wxBitmap bitmap(*self, depth);
             return bitmap;
         }