Sub-pizel Surface Fitting Algorithm in Digital Speckle Correlation Method

摘要：

Sub-pixel surface fitting technique is a way that fits out a correlation coefficient surface around the point getting by the integer pixel searching and locates the sub-pixel maximum point to get the subpixel movement. It is a key way to improve the displacement measurement accuracy in Digital Speckle Correlation Method (DSCM), meanwhile, it is more time consuming than other steps. Four sub-pixel surface fitting registration methods- Binary quadratic surface fitting, Gaussian surface fitting, Least square fitting of Gaussian surface and Lagrange surface fitting are proposed. Binary quadratic surface fitting is the fastest way; least square fitting of Gaussian surface can improve the accuracy but much more time consumption. The accuracy of biquadratic Lagrange surface fitting is extremely high while the speed is not too slow. All these surface fitting method are more suits for natural、 speckle than artificial one. These conclusions are proved by the results of the experimental system.

关键词： Displacement measurement Digital speckle correlation method (DSCM) Sub-pizel registration Surface fitting

作者: Yong Lv Qibo Feng Liangyu Qi Qingshan Chen

作者单位: School of Science,Beijing Jiaotong University,Beijing 100044,China Dept.of Optical Information Scien School of Science,Beijing Jiaotong University,Beijing 100044,China Dept.of Optical Information Science & Technology,Beijing Information Science & Technology University

会议类型: 国际会议

会议名称: 2009 9th International Conference on Electronic Measurement & Instruments(第九届电子测量与仪器国际会议 ICEMI2009)

会议地点: 北京

会议语种:英文

页码: 4187-4190

在线出版日期: 2009-08-16（万方平台首次上网日期，不代表论文的发表时间）