http://bugs.winehq.org/show_bug.cgi?id=16525
--- Comment #3 from H. Verbeet hverbeet@gmail.com 2008-12-17 03:13:31 --- The problem with that patch is that it essentially multiplies the channels by 4 or 8. That means that for the 5 bit components it maps the range 0..31 to 0..248, and for the 6 bit component it maps the range 0..63 to 0..252, rather than mapping both to 0..255.