I am looking for solving this problem with training a deep learning-based classifier or image processing techniques. ps. I exactly do not need to know how much is distance, I only need to know whether trucks are intruded the certain distance or not.
One possible approach will be to use an algorithm which detects lines (Ex. Hough lines or any deep neural net trained to detect lanes) and use some threshold range so that we can get the lane and the edges of truck, then after extracting the lines, you can easily find the distance between them.
Then you need to experiment out on few images to get the threshold distance that you are expecting the truck to maintain as the real distance and the distance calculated using images are not same
If you want to classify using deep learning, you may need to preprocess the images and send them. As it will become very difficult to directly learn to classify based on image, you may need to first detect the lanes, then apply a mask and then send the masked image to your network to make the network to converge.