Abstract
Calibration of multi-camera systems is a key task for accurate object tracking. However, it remains a challenging problem in real-world conditions, where traditional methods are not applicable due to the lack of accurate floor plans, physical access to place calibration patterns, or synchronized video streams. This paper presents a novel two-stage calibration method that overcomes these limitations. In the first stage, partial calibration of individual cameras is performed based on an operator's annotation of natural geometric primitives (parallel, perpendicular, and vertical lines, or line segments of equal length). This allows estimating key parameters (roll, pitch, focal length) and projecting the camera's Effective Field of View (EFOV) onto the horizontal plane in a base 3D coordinate system. In the second stage, precise system calibration is achieved through interactive manipulation of the projected EFOV polygons. The operator adjusts their position, scale, and rotation to align them with the floor plan or, in its absence, using virtual calibration elements projected onto all cameras in the system. This determines the remaining extrinsic parameters (camera position and yaw). Calibration requires only a static image from each camera, eliminating the need for physical access or synchronized video. The method is implemented as a practical web service. Comparative analysis and demonstration videos confirm the method's applicability, accuracy, and flexibility, enabling the deployment of precise multi-camera tracking systems in scenarios previously considered infeasible.
Abstract (translated)
多摄像头系统的校准是实现精确对象跟踪的关键任务。然而，在实际环境中，由于缺乏准确的平面图、放置校准图案的物理访问权限或同步视频流等原因，传统方法难以适用，使得该问题仍然具有挑战性。本文提出了一种新颖的两阶段校准方法，以克服这些限制。 在第一阶段，根据操作员对自然几何特征（平行线、垂直线和等长线段）的手动标记进行单个摄像头的部分校准。这允许估算关键参数（滚转角、俯仰角、焦距），并将在基础三维坐标系中的有效视野（EFOV）投影到水平面上。 在第二阶段，通过交互式调整投影的EFOV多边形的位置、比例和旋转来实现系统的精确校准。操作员根据平面图调整这些参数以使多边形对齐；若没有平面图，则使用虚拟校准元素投射至系统中的所有摄像头进行调整。这确定了剩余的外参（摄像机位置和偏航角）。该方法仅需每个摄像头的一张静态图像即可完成校准，无需物理访问或同步视频流。 本文的方法已实现为实用的网页服务，并通过比较分析和演示视频证明其适用性、准确性和灵活性，使在以前被认为不可行的情况下部署精确多摄像头跟踪系统成为可能。
URL
https://arxiv.org/abs/2512.05171
