This is my first post. I´m managing to perform an eye tracking tool to move the pc mouse. I´m using the c++ library openCV and common webcam placed at the top of the screen pc (it´s not an IR webcam!).
This is my first attempt so I´m using only one eye.
Till this moment I get the gaze vector for the eye. Let´s call it as "g".
To get the gaze vector I had attention to the vertical rotation and the horizontal rotation of the eye. (I can tell you how have I get it, but I dont´want to bore you with this now...)
Now I´ll have to know the point on the screen that is beeing pointed by the gaze line with the direction of the gaze vector.
I´m considering only one axes system (because unfortunatelly my math skills aren´t the best
), with its origin placed at the eye. Parallel to the eye we will have the screen plane. The user will be at a fixed position (say 20 cm from the screen-this is a request of the project). As the screen lies on the xy plane, our screen plane will have the equation : Z=20.So the line contained a vector will´ve the equation:
(x,y,z)=(x0,y0,z0)+gt
(x,y,z)=(0,0,0)+gt
so:
x=gxt; y=gyt; z=gzt (1)
to know the intersection point of the gaze line with the screen plane z=20 (screen plane) :
20=gzt<=>t=20/gz
This way we get t and we will substitute it in the equation (1) we will get the x y and z coordinates of the intersection.
Obviously that I will have to implement some conditions because the screen is a "limited" plane.
So what are your advices for me? Am I thinking wright? I know that If this step fails I will never achieve my goal...So your advices will be very important !
Thanks in advance for your time,
Eduardo
(PS: sorry for my english
)
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