Earlier conventional photogrammetric techniques were used in the topographic mapping using a large format digital camera known as aerial photogrammetry. Recent advancements in UAV technology for photogrammetric purposes have provided a necessity of state-of-the-art photogrammetric software for processing images acquired using UAV. These so-called drones come with an inbuilt GPS and IMU system to geotag the image at the time of acquisition. This information is saved as EXIF data inside the image. There are software programs that provide an end-to-end solution for processing photogrammetric data (UAV-acquired images). This software has the capability of processing data with or without EXIF data. The study provides information related to various camera calibration parameters inside the UAV, and if an externally installed RTK could be useful in generating more accurate deliverables using photogrammetric processing. In UAVs, exterior orientation or EO are saved in both aircraft as well as in gimbal, so through this research, it was tried to look into in-depth of all the black box processes that are going on in the software. This study also provides a solution to the accuracy problems with the UAV-based photogrammetric survey methods.

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摄影测量软件的工作原理：基于无人机外部方向参数的视角

早期的传统摄影测量技术用于使用称为航空摄影测量的大幅面数码相机进行地形测绘。用于摄影测量目的的无人机技术的最新进展为处理使用无人机获取的图像提供了最先进的摄影测量软件的必要性。这些所谓的无人机带有内置的 GPS 和 IMU 系统，可在获取图像时对图像进行地理标记。此信息保存为图像内的 EXIF 数据。有一些软件程序可以为处理摄影测量数据（无人机获取的图像）提供端到端的解决方案。该软件具有处理带或不带 EXIF 数据的数据的能力。该研究提供了与无人机内部各种相机校准参数相关的信息，如果外部安装的 RTK 可用于使用摄影测量处理生成更准确的可交付成果。在无人机中，飞行器和万向节中都保存了外定向或 EO，因此通过这项研究，试图深入研究软件中正在进行的所有黑匣子过程。本研究还为基于无人机的摄影测量方法的精度问题提供了解决方案。