基于多项式变形法的栅格图像非线性畸变校正  

Nonlinear Distortion Correction of Grid Image Based on Polynomial Warping Method

作　　者：郑毅[1,2,3] 郑苹[4] 

机构地区：[1]南京航空航天大学民航飞行学院,南京市讲师210016 [2]西安电子科技大学 [3]山东工商学院 [4]华中科技大学

出　　处：《工具技术》2013年第10期70-72,共3页Tool Engineering

基　　金：国家自然科学基金资助项目(60970105;61173173);山东省自然科学基金资助项目(ZR2012FL09);山东省住房和城乡建设厅科技项目(2011YK060);山东省高等学校科研计划(J11LG12)

摘　　要：为了减小光电成像测量系统存在的非线性畸变,提高测量精度,提出了一种基于多项式变形法的栅格图像畸变校正方法。提取带有桶形畸变的栅格图像中的栅格交叉点作为控制点,利用光学成像关系推算出栅格交叉点的理想无畸变位置,构成控制点对。对畸变图像和校正后图像的像素位置对应关系建立线性方程组,通过最小二乘法实现两者像素之间的坐标变换,并且采用双线性插值法确定校正后栅格图像中像素的灰度值。对带有桶形畸变的栅格图像进行了畸变校正实验,结果表明,多项式变形法能够自动、有效地校正图像畸变。In order to decrease nonlinear distortion of electro - optical imaging measurement system, a distortion cor- rection method based on polynomial warping method is proposed to improve measure precision. Cross points of the black lines can be found and regarded as control dots by image segmentation and thinning of a grid image with barrel distortion. According to imaging characteristic of an optical system, coordinates of cross points in an undistorted image can be calcu- lated from ones in the distorted grid image. Based on relationships among pixel locations of the distorted image and undis- totted image, linear equations can be set up. Coordinates transformation is performed by least - squares method. And in- tensity information of pixels can be computed by bilinear interpolation method. The proposed method is tested to correct the grid image with barrel distortion. Experimental results show that the proposed method can correct image distortion automati- cally and efficiently.

关 键 词：图像处理 畸变校正 多项式变形 双线性插值 

分 类 号：TG806[金属学及工艺—公差测量技术] TP391.41[自动化与计算机技术—计算机应用技术]