@subsection Commands
-This filter supports the following command:
+This filter supports the following commands:
@table @option
@item x
-Set the @option{x} option expression.
-
@item y
-Set the @option{y} option expression.
-
@item enable
-Set the @option{enable} option expression.
+Modify the x/y and enable overlay of the overlay input.
+The command accepts the same syntax of the corresponding option.
+
+If the specified expression is not valid, it is kept at its current
+value.
@end table
@subsection Examples