This paper considers the design and analysis of lane marker parameters in 2-D images. Five different parameters, which have high correlation to the steering angle of a vehicle, are proposed, and their correspondence to the steering signal is analyzed. The parameters are based on the position, angle, area, and curvature of the lane marker and have not been reported in the literature before, except the curvature. A new derivative-free method is proposed for curvature estimation. The stability of the proposed parameters is analyzed with respect to the look-ahead distance. Possible application of the parameters for overtaking detection is presented. This paper is performed using signals from real country road driving.