一种Zernike矩的高精度板材尺寸测量方法

An Accurate Zernike Moment-Oriented Method for Measuring Flat Strip Dimension

目前技术条件下,对于大视场的高精度边缘测量而言,工业级面阵CCD传感器的分辨率难以满足要求.文章针对钢板尺寸测量系统,首先介绍了测量环境和工作原理.继而在Zernike矩以及Zernike矩亚像素精度边缘检测原理的基础上,提出了适用于钢板尺寸测量的亚像素精度边缘检测算法.该算法不仅具较好的抗噪性能和检测精度,而且在传统界定边缘点的阈值处理方法上进行了改进,使边缘受限于单个像素的宽度范围内,能够实现亚像素精度的定位.系统实际运行表明,该方法能够有效提高测量精度,具有良好的效果和实用价值.

Currently,the resolution of industrial-grade array CCD sensor can hardly satisfy the high precision requirements on the edge detection across a huge field. For the system of steel plate dimensional measurement,this paper introduces running environment and operation principle. Then,it proposes a sub-pixel level edge detection algorithm for steel plate dimensional measurement based on Zernike moment and also its theory applied to sub-pixel detection. This algorithm has good anti-noise performance and high detection precision. Moreover the proposed algorithm also improves the traditional threshold method for processing edge points,which can obtain an edge within a single pixel width and the location in sub-pixel level.In practice,the results showthat the proposed algorithm improves the measurement accuracy and has efficient effect as well as practical value.