Hough 变换的运算精度及其运算速度，在高速、高精度工作环境下具有重要的意义，提出了一种改进的Hough 变换的直线提取算法。通过对零件图像预处理、改进的Hough 变换处理，实现了快速、高精度地轴类零件轮廓直线的检测。利用C＋＋编程，采用OpenCV，针对某轴类零件轴径的非接触检测，实现了改进的Hough 变换的直线提取算法。

A line extraction algorithm based on improved Hough transform was proposed to realize non-contact measurement of shaft component. It processed the image by pre-treated, improved Hough transform to realize detecting the shaft component outline more quickly and with high-precision. The method which detects diameter of one shaft is realized by using OpenCV in C＋＋ Builder programming environment.