Yu Jian, Da Feipeng, Li Wenjian
IEEE Trans Image Process. 2021;30:783-793. doi: 10.1109/TIP.2020.3038514. Epub 2020 Dec 4.
A newly developed calibration algorithm for camera-projector system using spheres is presented in this paper. Previous studies have exploited image conics of sphere to calibrate the camera, whereas this approach can be strengthened to apply in the projector and ultimately achieve the overall calibration for single or multiple pairs of camera-projector. Following the concept of taking the projector as an inverse camera, we retrieve the image conic of the sphere on the projector plane based on a pole-polar relationship we found. At least 3 image conics on the image plane of each device are required to calculate the intrinsic parameters of the device. The extrinsic parameters for all devices in the system are determined by the position of sphere centers in each coordinates frame of the device. Based on the isotropy of the calibration object (sphere), this work is mainly interested in accomplishing the entire calibration for multiple camera-projector systems in which sensors surround a central observation volume. Experiments are conducted on both synthetic and real datasets to evaluate its performance.
本文提出了一种新开发的使用球体的相机-投影仪系统校准算法。以往的研究利用球体的图像二次曲线来校准相机，而这种方法可以得到强化，以应用于投影仪，并最终实现单对或多对相机-投影仪的整体校准。遵循将投影仪视为反向相机的概念，我们基于发现的极线-极点关系检索投影仪平面上球体的图像二次曲线。每个设备的图像平面上至少需要3条图像二次曲线来计算设备的内参。系统中所有设备的外参由球体中心在设备每个坐标系中的位置确定。基于校准对象（球体）的各向同性，这项工作主要致力于完成多个相机-投影仪系统的整体校准，其中传感器围绕着一个中央观察区域。在合成数据集和真实数据集上都进行了实验，以评估其性能。
