I am working on Vision based vehicle lane keeping control system. I have uploaded two images at https://tinypic.com/view.php?pic=24gj85t&s=6 & at https://tinypic.com/view.php?pic=2pyvvps&s=6. According to my understanding; my system has two parts; image processing and control systems. Image processing part has to detect the road lane markings and then to calculate the lateral distance between the vehicle C.G. and the centre line of road. Control system part has PID controller; Whose job is to keep the vehicle in the centre of the lane. In second block diagram; Reference is input to the PID; which represents where we want our vehicle to be. Next to it space state block is attached in which mathematical modelling of the car is done.The output of PID is steering angle. I am confused with the interconnection of the blocks. I have no idea where to connect the image processing part and where to take feedback according to second block diagram.