基于改进FAST和BRIEF的双目视觉测量方法  

Binocular Vision Measurement Method Using Improved FAST and BRIEF

作　　者：宋超群 许四祥[1,2] 杨宇 化猛奇 Song Chaoqun;Xu Sixiang;Yang Yu;Hua Mengqi(Anhui Province Key Laboratory of Special Heavy Load Robot,Anhui University of Technology,Maanshan,Anhui 243032,China;School of Mechanical Engineering,Anhui University of Technology,Maanshan,Anhui 243032,China)

机构地区：[1]安徽工业大学特种重载机器人安徽省重点实验室,安徽马鞍山243032 [2]安徽工业大学机械工程学院,安徽马鞍山243032

出　　处：《激光与光电子学进展》2022年第8期163-170,共8页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(51374007);安徽高校自然科学研究重点项目(KJ2020A0259);特种重载机器人安徽重点实验室开放基金(TZJQR005-2021)。

摘　　要：针对传统features from accelerated segment test(FAST)算法检测到的角点存在聚簇现象和阈值依靠人为确定,图像匹配算法匹配准确率较低和双目视觉测量精度较低等问题,提出一种基于改进FAST和binary robust independent elementary features(BRIEF)的双目视觉测量方法。首先用FAST算法提取出特征点,简化检测模板,同时用自适应阈值提取特征点;然后用改进的BRIEF描述特征点,用像素点邻域的灰度平均值进行比较形成描述子;之后用汉明距离完成匹配;最后用灰度梯度法得到匹配点的亚像素坐标,根据视差和三角测量原理计算出匹配点的三维空间坐标,从而完成被测物体的尺寸测量。实验结果表明:在角点检测方面,改进的FAST检测到的角点更均匀;在图像配准方面,通过与其他算法进行对比,验证了所提方法能有效地提高匹配准确率;在测量方面,所提方法测量的最低相对误差为0.45%,满足测量要求。The detection using traditional features from accelerated segment test(FAST)algorithm showed the existence of clustering corner phenomenon and the threshold value depended on artificial determination.Further,the detection using image matching algorithm showed that the matching and binocular vision measurement accuracies are low.In this paper,we proposed a binocular vision measurement method using improved FAST and binary robust independent elementary features(BRIEF).First,the FAST algorithm was used to extract the feature points and simplify the detection template.Next,the adaptive threshold was used to extract the feature points,which are described using the improved BRIEF,and the descriptor was formed by comparing the gray average of the neighborhood of a pixel.Then,it was based on the Hamming distance to complete the match.Finally,we adopted the gray gradient method to obtain the subpixel coordinates of the matching points.The threedimensional spatial coordinates of the matching points were calculated using the principle of parallax and triangulation,to complete the size measurement of the measured object.From the experimental results,the corner points detected using the improved FAST are more uniform with regard to corner detection,verifying that the proposed method effectively improves the matching accuracy compared with other algorithms.Besides,the minimum relative error of measurement of proposed method is 0.45%,which satisfies the measurement requirements.

关 键 词：图像处理 双目视觉 FAST算法 BRIEF描述符 灰度梯度法 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]