What colour model does the image use in PIL

[Johny]

On Nov 7, 2:53 pm, Hrvoje Niksic <hnik... at xemacs.org> wrote:
> Johny <pyt... at hope.cz> writes:
> > I use PIL and with it im.getpixel((x,y)) to find out the colour of a
> > pixel.  But how can I find out in which color model the the return
> > value is?
>
> im.mode gives you a string such as 'RGBA' or 'CMYK'.  im.getbands()
> returns a tuple such as ('R', 'G', 'B', 'A').

Thank you for your help.
Can you please help me once more?
Now I would need to apply a threshold value to the image, where
everything above a certain brightness level becomes white, and
everything below the level becomes black.
How can I do that with PIL?
Thank you
L