从单幅图像中识别道路消失点，是无人驾驶、智能导航等领域的关键技术之一。针对城市典型道路和街道图像，提出了一种新的基于垂线包络和平行线对的城市道路图像消失点检测算法。提取单幅图像中的所有平行线对，利用图像中存在的竖直线，提出了竖直区域的包络线估计方法，并实现了对道路区域的分割，有效提取了道路区域内的平行线对。使用方向分组策略将道路区域平行线分成两类，并对近似对称的直线对求交点。利用C-means聚类和统计相结合的方法估计了城市道路场景中的消失点。实验结果表明，该算法能够准确有效地估计城市道路场景中的消失点。

Identifing the road vanishing point from a single image is one of the key technologies in unmanned, intelligent navigation and other areas. A new vanishing point detection algorithm based on the envelope of perpendicular and parallel lines is proposed for typical urban road and street images. All parallel line pairs in a single image are extracted, vertical lines present in the image are used to propose on envelope estimation method to segment the road area and extract the parallel line pairs in the road area effectively. Grouping in different directions is used to divide the road parallel lines into two categories, and the intersections of the approximately symmetrical lines are solved. By using the C-means clustering and statistical method, the vanishing point in the city road scene is estimated. The experimental results show that the proposed algorithm can estimate the vanishing point in the urban road scene accurately and effectively.