How to plot cubic b-spline equation to detect the curve road for application of lane detection ?

Im doing project on lane detect and tracking using B-snake model. Based on my knowledge, B-snake model use B-spline function to find the curve of shape. My problem is I don't have any idea how to apply B-spline function to this project so that it can detect the curve accurately using its control point. Figure below is my original image :

And my work progress is up until this image. This is stage where the mid-line of the road is estimated based on left and right lane. My project is same as on this site Initialzation B-snake control points using CHEVP algorithm

Based on what I've read, after this stage, which is the mid-line estimation, the B-snake will iteratively find the lane detection. And I have no idea how to get image in figure (d) :

I hope someone can have solution for this.Sorry if the question is not understandable

[Sapan Doshi]

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.106.6644&rep=rep1&type=pdf Here they consider parameter mid line parameter k. As you can see in eq 12, k is nothing but the linear slope from base line middle point to vanishing point. So, after you have determined k, you can find the mid lane points, Pm4, Pm3,Pm2,Pm1, Pm0. Calculate Q1, according to 13. And now you know the knots of B-spline curve.

[anju anju]

Could you tell me the curve line of the curve? This is my email address please

contact [e-mail]

[anju anju]