特征平行直线的成像畸变现场校正  

A Distortion Field-calibrating Method Based on Feature Parallel Lines of Image

作　　者：汪贵平[1,2] 王会峰[1,2] 刘盼芝[1] 巨永锋[1,2] 

机构地区：[1]长安大学电子与控制工程学院,西安710064 [2]陕西省电工电子实验示范教学中心,西安710064

出　　处：《光子学报》2014年第1期87-91,共5页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.41101357;61107007);陕西省教育厅科研计划(No.12JK0806);陕西省科学技术研究发展计划(No.2013K09-17)资助

摘　　要：针对畸变对成像测量的影响,通过对摄像机畸变模型的分析,提出了一种基于特征平行直线的畸变现场校正方法.该方法分两步,非线性径向畸变的校正和透视畸变的校正.首先,提取图像中包含的多条特征直线,然后通过迭代法将成像后的弯曲直线拉直的方法获得系统非线性径向畸变参量,再用这些参量对非线性径向畸变进行校正,得到去非线性径向畸变的图像.通过对图像中的特征平行直线进行拟合,获得系统的透视畸变参量,并以这些参量反演迭代实现对透视畸变的校正,进而得到去透视畸变的图像.实验和仿真结果表明:该方法通过两步法利用图像中的特征平行直线先验知识能够有效实现对成像中多种畸变的一靶现场校正;对像机径向畸变和透视畸变的校正后相对误差均达到5%以内,适合于工程中基于图像的测量和目标识别中目标无固定位置的复合畸变的现场校正.Considering the effect on the image measurement system, a distortion calibration method was designed after analyzing the model of lens distortion. The method consists of two steps, namely calibration on the non-linear distortion and calibration on the perspective distortion, In the first step, the non-linear distortion coefficients of the lens were obtained form drawing the multi feature straight lines and straightening the feature lines. With these coefficients, the non-linear of the image was calibrated, and an image without any non-linear distortion was achieved. In the second step, the distortion parameters were obtained through fitting the parallel line feature of the image. With these parameters, the perspective distortion was calibrated, and an image without perspective was achieved. The experiments and simulations show that the radial and the perspective-distortion relatively error can be reduced to 5 % with this method, which can be used in many similar engineering systems based on image measurement and target recognition in non-fixed locations.

关 键 词：成像测量 径向畸变 透视畸变 平行直线拟合 无畸变 误差 现场校正 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]