基于SURF-OKG特征匹配的三维重建技术

3D reconstruction technique based on SURF-OKG feature matching

为了解决结构光三维重建中传统立体匹配存在的特征点匹配错误、匹配缺失和匹配重复等问题,本文将SURF算法中高斯滤波改进为自适应中值滤波结合小波变换,并提出了一种基于OKG算法的二次特征匹配方法。该算法首先使用自适应中值滤波结合小波变换算法对图像进行平滑和降噪处理,再进行初步特征点提取和匹配,然后将构建的尺度空间划分成多个网格,在每个网格内使用FAST算法提取尺度空间特征点,使用ORB算子提取左右图像的特征点,用BRIEF描述子对其进行描述,采用K-D树最近邻搜索法限制特征点选取,通过GMS算法剔除误匹配点。最后,将本文SURF-OKG算法与传统特征匹配算法进行对比分析,并对阶梯块进行三维重建来验证本文算法的有效性。实验结果表明:SURF-OKG算法的正确匹配率为92.47%;对阶梯宽度为40 mm,精度为0.02 mm的阶梯块进行三维重建,实验测得阶梯宽度的误差均值为1.312 mm,最大误差值不超过1.72 mm,基本满足结构光三维重建系统的实验要求。

To address issues such as incorrect feature point matching,missing matches,and duplicate matches in the traditional stereo matching of structured light-based 3D reconstruction,this study intro⁃duced enhancements to the Gaussian filtering in the SURF algorithm through the integration of adaptive median filtering with wavelet transform.Additionally,a secondary feature matching approach based on the OKG algorithm was proposed.The proposed algorithm first employed adaptive median filtering in con⁃junction with the wavelet transform algorithm to achieve image smoothing and noise reduction.Subse⁃quently,preliminary feature point extraction and matching were performed.The scale space was then di⁃vided into multiple grids.Within each grid,the FAST algorithm was employed to extract scale space fea⁃ture points,the ORB operator was utilized to extract feature points from the left and right images,and these points were described using BRIEF descriptors.The K-D tree nearest neighbor search method was applied to constrain feature point selection,and the GMS algorithm was utilized to eliminate mismatches.Finally,a comparative analysis was conducted between the SURF-OKG algorithm proposed in this paper and traditional feature matching algorithms.The effectiveness of the proposed algorithm was verified through the 3D reconstruction of step blocks.Experimental results reveal that the correct matching rate of the SURFOKG algorithm is 92.47%.In the case of step blocks with a width of 40 mm and an accuracy of 0.02 mm,the mean error in width measurement is 1.312 mm,with no maximum error exceeding 1.72 mm,meeting the experimental requirements of the structured light 3D reconstruction system.