Which hinges for bi-fold doors?

Hi, I have a bi-fold door on a built-in wardrobe, I'd like to replace the hinges as they have been covered in paint and are brass where as the rest of the hinges, handles etc in the room are chrome. The trouble I'm having is finding the right type of hinge to replace them with, can anyone help?!

I need a hinge where the plate meets the pin in the middle not at the bottom, the attached pics should make sense

I saw these in B&Q attached to a set of bi-fold doors on sale, these are what I want, but they didn't sell them separately.

This hopefully shows was I mean

Thanks
Nigel

 

Thanks Sheelin, I know the one in the pic attached to the door is a flush hinge as appose to a butt hinge, I've found a flush hinge the right size (75mm) but it lines up wrong, as in my quick sketch, the plate meets the barrel at the bottom and not in the middle, is this a 'special' flush hinge?