Automatic Calibration of an All-Sky Camera Based on Constellation Recognition
-
摘要: 全天空相机鱼眼镜头的固有畸变会显著改变像素坐标与真实方位角和天顶角的映射关系,需要通过高质量的训练星点进行几何校正才能进行物理分析。由于镜头校正模型的初值敏感性,传统的基于人工标注或规则匹配的校准方法存在效率与准确性难以兼顾的问题,本文提出了一种基于星座识别的全天空相机自动校准方法。该方法首先通过深度学习技术自动构建高质量训练星点来初始化镜头校正模型,再通过逐步扩展训练星点迭代提升镜头校正模型的精度。在子午工程兴隆站全天空气辉成像仪的观测数据上实验显示,星座识别mAP50-95 达到0.985,由星座初始化的镜头几何校正最终方位角与天顶角校正误差均在2' 以内,显著优于传统基于距离匹配的方案45' 以内。本研究为全天空相机的自动化校准提供了一种高效且高精度的解决方案。Abstract: The intrinsic distortion of the fisheye lens in an all-sky camera can significantly alter the mapping between pixel coordinates and the true azimuth and zenith angles, making high-quality training star points essential for geometric correction prior to physical analysis. Because lens calibration models are sensitive to their initial parameters, traditional calibration methods based on manual annotation or rule-based matching often struggle to achieve both high efficiency and high accuracy. In this study, we propose an automated calibration method for all-sky cameras based on constellation recognition. The method first uses deep learning to automatically construct high-quality training star points to initialize the lens calibration model, and then iteratively improves the calibration accuracy by progressively expanding the training set. Experiments on observational data from an all-sky airglow imager at the Xinglong station of the Meridian Project show that the constellation recognition model achieves an mAP50-95 of 0.985, and the resulting geometric calibration yields azimuth and zenith-angle correction errors within 2' , significantly outperforming a conventional distance-matching approach (within 45' ). This study provides an efficient and high-precision solution for automated calibration of all-sky cameras.
-
-
计量
- 文章访问数: 17
- HTML全文浏览量: 3
- PDF下载量: 0
-
被引次数:
0(来源:Crossref)
0(来源:其他)
下载: