ken sent the following bits through the ether:

>  I have two image, A is a photo, B is a part of A. How can I know
>  where (x,y) is the photo B in Photo A?

If B is an exact partial image of A then look at the images like a
string and look for the right seqeuences of colours. A more
interesting case is covered by the following paper (interesting links
too): http://citeseer.nj.nec.com/336979.html

Hope this helps, Leon
-- 
Leon Brocard.............................http://www.astray.com/
Nanoware...............................http://www.nanoware.org/

.... Brain over - Insert coin