Originally posted by knutso
I don't know if this is of any help?
Note that this link has some coding errors (I think it does not work for bitmaps > 256 colors) and explanation errors (they talk about one structure when they mean the other), so you should read the comments. I am not even sure if all of the comments point out all of the errors. They should update the page - I just wrote them an email to do so, so no further people will be mislead by it.