some help with a project i working on

hello,
i did not know where to post my question so i post it here, hope its ok.

well, i got an a4 paper that have 1cm red border.

i want that the camera live recognize the border and i want to get the point (x, y) of the paper relative to the center of the iphone screen.

i can pay for this function.

thank you,
avi sharvit,
sharvita@gmail.com