A question to Lavolpe or anyone who can answer

i'm trying to get the color table of a 8bpp bmp with this API:
GetDIBColorTable
but the table is so bad
and the resulting bmp different from the origin

my steps are:
1. loading a 8bpp bmp via loadimage
2. creating comptiabledc from the desktop dc
3. select the bmp into it.
4. calling GetDIBColorTable

the color table is filled with different colors from the origin (i think)
because the result bmp different.

thanks in advanced.