由任意平行四边形确定摄像机内参数的方法

A Novel Approach for Determining Intrinsic Parameters of Camera Using Two Parallelograms

根据交比与角度之间的联系,提出了一种由任意平行四边形标定摄像机内参数的线性方法.采用关于空间平面上平行四边形的2种不同方案,运用拉盖尔定理和交比不变性原理,计算2个圆环点的图像坐标,再利用圆环点在绝对二次曲线上这一特点来线性标定摄像机内参数,完成标定只需3幅图像.文章将以往通过正交直线求圆环点的方法进行了扩展,采用任意斜交直线也可求圆环点,因而具有更广泛的适用性.模拟实验和真实图像实验均证明了该方法的可行性.

According to the relationship between cross-ratio and angle, a novel linear approach was pro- posed to determine the intrinsic parameters of the camera. The image coordinates of the two circular points were derived from two different methods concerning the images of two parallelograms using the Laguerre theorem and the invariance of cross-ratio. Then the intrinsic parameters of the camera are linearly calibra- ted from three images of parallelograms according to the circular points which are in the absolute conic （AC）. Compared with the calibration method based on rectangles, this approach further weakens the re- quired conditions. Therefore, it has a wide applicability. Extensive simulations and experimental results with real images show that the proposed approach is practicable.