Road shape reconstruction by local flatness approximation

A new algorithm is presented for reconstructing the three-dimensional (3-D) road shape from camera images for the purposes of navigating autonomous land vehicles. The approximation that the road surface is locally flat enables us to determine a one-to-one correspondence between the two road boundaries, which together with our knowledge about roads (the 'model' of roads) determines the 3-D road shape. In order to cope with the inaccuracy of image data, a least-squares curve-fitting technique is proposed, and the behaviours of image noise are analysed. Some examples based on real images are given.