非线性畸变分布椭圆鱼眼镜头成像建模和校正

Imaging modeling and correction of nonlinear distortion distribution ellipse fish-eye lens

非线性畸变分布椭圆鱼眼镜头是面向视频监控应用的一种新型鱼眼镜头,与传统的鱼眼镜头不同,非线性畸变分布椭圆鱼眼镜头采用非角对称光学系统设计原理,其有效成像面为椭圆,并且采用非线性畸变分布成像函数,能够实现对大视场中关键区域的增强畸变。通过对其非相似成像的研究,建立一种全方向光线跟踪下的镜头成像混合畸变模型,使用B样条曲面和曲线分别拟合径向和切向畸变函数,然后通过五面立体角度标定空间实现对镜头成像函数的精确标定,最后实现畸变图像的校正。

Nonlinear distortion distribution ellipse fish-eye lens is a new fish-eye lens facing to video surveillance ap- plications, and it adopts non angular symmetric optical system design principle, which is different from that of tradi- tional fish-eye lens, and its effective imaging area is an ellipse. The lens adopts the nonlinear distortion imaging function, and it can achieve enhanced distortion in the critical areas of the large field of view. In this paper, a lens imaging hybrid distortion model under full direction ray-tracing is established, and B-spline surfaces and curves are used to fit the radial and tangential distortion functions, respectively. Then a five-sided three-dimensional angle cali- bration space is adopted to achieve accurate calibration of the imaging functions of the lens, and finally achieve the image distortion correction.