This work presents an artificial vision-based monitoring system for urban environments. It comprises a fisheye camera monitoring the scenes 180ox360o hemisphere and a Pan-Tilt-Zoom camera capturing narrower regions of interest in high-resolution. The ONVIF protocol standard is used to interface both IP-cameras, allowing for the integration of camera control (image acquisition and movement) and geometric calculations on a single device. The events of interest (motion of vehicles and pedestrians) are assumed to happen on the ground plane. This assumption is required to solve the back-projection, the function that maps coordinates in the highly distorted images of the fisheye camera to the ground plane. A calibration strategy estimates the poses of the cameras without placing restrictions on their orientations or relative distance. It optimizes the back-projection error in the ground plane instead of the re-projection error in the image. Finally, a simple pointing and zoom adjustment strategy controls the Pan-Tilt-Zoom camera. The system is tested in controlled laboratory conditions and shows accurate outdoor performance for pedestrian observation.

中文翻译：

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基于鱼眼和云台摄像机的城市双模视频检测系统


这项工作提出了一种基于人工视觉的城市环境监测系统。它包括一个监控 180x360o 半球场景的鱼眼摄像头和一个以高分辨率捕捉较窄感兴趣区域的平移倾斜变焦摄像头。 ONVIF 协议标准用于连接两个 IP 摄像机，允许在单个设备上集成摄像机控制（图像采集和移动）和几何计算。假设感兴趣的事件（车辆和行人的运动）发生在地平面上。这个假设是解决反投影问题所必需的，该函数将鱼眼相机高度扭曲的图像中的坐标映射到地平面。校准策略估计相机的姿态，而不对其方向或相对距离施加限制。它优化了地平面中的反投影误差，而不是图像中的重投影误差。最后，一个简单的指向和变焦调整策略控制平移-倾斜-变焦相机。该系统在受控实验室条件下进行了测试，并显示出用于行人观察的准确户外性能。