Eye tracking where are you looking at the screen

I'm working on real-time eye tracking using a webcam. I want to know how can I draw eyes movements where are you looking at the screen?

My program currently finds centres of eyes and draws it.

For example my screen 1366x768 pixels and if the user looks at the right-top of the screen, the program will give (0 768) or midpoint of the screen (683 384).

How can I do that? What is the references point? Can I use calibration or different methods? Thankyou

Answer 1

[Michaelscheinfeild]

i suppose you need to know the distance to screen and make some virtual line from eyes to screen so you will hve some mapping eye location xy->screen uv