双频曲线拟合线结构光条纹中心提取方法

Extracting Method for Light Strip Center of Linear Structural Light Based on Dual Frequency Curve Fitting

提出了一种双频曲线拟合的亚像素中心提取方法。首先采用二次阈值法自动分割光条区域,利用灰度重心法获取光条纹中心初始位置,然后用移动直线拟合初始位置得到光条曲线的局部法线,最后在法线方向上进行双频曲线拟合,得到光条纹中心的亚像素坐标。实验结果表明,该方法能消除部分高频噪声的影响。相比Steger法,该方法提取的条纹中心均方根误差小于0.1 pixel,速度约是其26倍,可适用于多种材质表面光条纹中心的提取,为工业应用中的激光条纹中心提取提供参考。

In this paper,a sub pixel center extraction method is proposed based on dual frequency curve fitting.First,twice threshold method is used to automatically segment light stripe region,and gray-gravity method is used to obtain the initial position of the light stripe region.Then,a normal moving linear fitting is designed to obtain the local normal of light strip curves.Finally,the sub-pixel center coordinate of the light strip is extracted precisely through dual frequency curve fitting of pixel data in the normal direction.Experimental results show that this method can partially eliminate the influence of high-frequency noise.Compared with Steger method,the root mean square error of the strip center extracted by this method is less than 0.1 pixel,and the speed is about 26 times of it.This method can be applied to the extraction of light stripe center of various materials,which provides a reference for the extraction of laser stripe center in industrial applications.