一种车轮轮廓的自动提取方法

An Automatic Approach for Detecting the Contours of Wheels

提取车轮轮廓是交通事故现场处理系统中的一个关键问题,其精度将直接影响现场测量的精度和勘查质量.本文提出了一种鲁棒地提取车轮轮廓的方法.由于提取钢圈轮廓比提取车轮橡胶轮廓容易,而且钢圈轮廓和车轮轮廓可以近似看作同一平面上的两个同心网,所以在本文中,我们首先提取钢圈轮廓、钢圈圆心(即车轮圆心)和车轮与地面接触点在图像上的投影,然后利用射影变换保持交比不变的性质求出车轮轮廓.大量不同天气下图像的实验结果验证了该方法的有效性.

The contours of wheels play an important role in the traffic accident analysis system. Their detecting precision will influence the measurement precision and the investigation quality directly. A new automatic detecting approach is proposed in this paper. As the contour of a wheel rim is easier to detect than the contour of a wheel, and the contour of a wheel rim and the contour of a wheel are approximately concentric circles on the same plane, we first detect the contour of the wheel rim, the center of the wheel rim and the contacting point between the wheel and the ground, then we detect the contour of the wheel via the invariance of cross ratio under projective transformation. Our extensive experimental results with real images under various weather conditions show that the proposed approach is capable of detecting contours of wheels robustly and automatically.