基于非均匀采样的图像射影畸变硬件校正  

Hardware Implementation with Non-uniform Sampling for Image Rectification of Projective Distortion

作　　者：蒋伟平[1] 王晓年[1] 蒋平[1] 朱劲[1] 

机构地区：[1]同济大学电子与信息工程学院,上海201804

出　　处：《数据采集与处理》2011年第2期200-206,共7页Journal of Data Acquisition and Processing

基　　金：国家高技术研究发展计划("八六三"计划)(2006AA04Z222)资助项目

摘　　要：当摄像机的像平面与拍摄面不平行时,图像必然发生射影畸变,给后续的图像处理和模式识别带来不便。现有校正方法大都在得到畸变图像后,通过实时计算或者查阅畸变表恢复图像像素间的度量关系。本文提出了一种基于非均匀采样的硬件图像校正采集系统,通过FPGA控制A/D采样器对模拟图像信号进行非均匀采样,实现图像的实时畸变校正和采集。为减小采样误差,还提出了一种倍频方案。仿真表明本系统可以代替软件校正算法,其硬件系统可拓展至其他应用。When an image plane and a physical surface are not parallel,projective distortion will occur.It is inconvenient for subsequent image processing and pattern recognition because of such image distortion.Nowadays,the software based rectifying methods depend on either online calculation or a distortion look-up table to restore the image measurement.A non-uniform sampling based hardware system for image rectifying is proposed in this paper,in which an FPGA is designed to control an ADC for non-uniform sampling of the video signal,so that the distortion correction and image acquisition are fulfilled simultaneously.To reduce sampling error,a frequency doubling scheme is also proposed.The simulation experiments show that the system can achieve real-time image rectifying,instead of the traditional software correction,and the developed hardware module can be extended to other applications which require real-time homographic mapping.

关 键 词：非均匀采样 射影畸变 FPGA 图像校正 单应关系 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]