提出了一种亚像素光带中心线实时提取方法。首先，通过跟踪光带轮廓线并进行多边形表示将光带分段；然后，利用轮廓线的逆时针排序特性以及分段光带方向和横截面方向的正交关系，采用序号表示方法计算光带横截面扫描线方向；最后，在扫描线上设计了自适应光带横截面宽度变化的灰度重心法计算亚像素坐标。针对6传感器线激光人脚扫描仪采集的分辨率为640 pixel×480 pixel的典型位置光带位图进行了实验，结果显示，采用本方法提取光带中心线用时不超过3.1 ms，精度达到亚像素级，能够满足多传感器线激光扫描视觉系统对光带中心线提取的实时性和高精度的要求。

A method to extract a light stripe central line with sub-pixel precision in real time was presented. First, the light stripe was segmented by light stripe contour tracking and the contour polygon representation. Then, based on the counter-clockwise sorting characteristics of contour and the orthogonal relationship between cross section direction and corresponding segmented light stripe direction, the scanning line direction of segmented light stripe was calculated by using a serial representation method. Finally, an adaptive barycenter method that can change adaptively the cross section width was designed on the scanning line to calculate the center sub-pixel coordinates. For the 640 pixel×480 pixel light stripe bitmaps captured by a 3D laser foot scanner with 6 CCDs at typical positions, the extraction time for central line is less than 3.1 ms in sub-pixel precision. The algorithm proposed here can satisfy the requirements of multi-sensor line laser scanning vision measurement system for real time, high precision as well as high speeds.