一种基于亮度阈值的激光光斑中心定位算法

摘要

激光光斑图像的光斑中心定位是激光位移检测中的关键技术之一.为提高桥梁挠度测量系统的实时性能, 本文针对测量中激光光斑图像的特点, 提出了一种确定光斑中心位置的方法.利用激光图像中光斑区域与其它区域亮度差别较大的特点, 确定亮度阈值并将光斑图像进行二值化处理, 得到一幅仅有激光光斑的图像, 根据圆上平行弦的中点连线通过圆心的原理, 通过求弦的中点确定圆心.本方法原理简单, 计算量小, 计算速度快, 能够满足测量系统的实时性要求, 已在测量实验中取得了较好的效果.%Center locating of laser spot is the key technology to laser displacement measurement.In order to improve the real-time performance of bridge deflection measuring system, this paper proposed a method of center locating of laser spot for laser image.The light intensity of laser spot is much larger than the intensity of other region.According to this characteristic, an intensity threshold is defined in order to get the binary image which only has laser spot.The principle is used to fit the center of laser spot that the midpoints of all parallel chords are in one straight line which is through the center of a circle.This method is simple, and has less calculation, so the measuring system using this method will be fast, and meets the demand of the real-time capacity.A good result has been achieved in measuring equipment.