从控制点到控制片

From Ground Control Point to Digital Control Photo

基于数字正射影像和数字高程模型等地理编码数据的“云控制”模式在中小比例尺影像的应用日趋成熟,但其本质仍是从物方获取控制点,数据产品中的误差导致其难以应用于大比例尺测图场景。基于已知精确几何定位参数和空三加密点的原始影像构建约束是理论更优的云控制模式。提出将这种由像方出发的云控制模式发展为一种标准化的测绘产品,即控制片,以期在更好地保障定位精度的前提下,降低重访航测任务中的重复劳动和算力消耗;介绍了控制片在大幅面航空相机检校、无人机影像和卫星影像几何定位方面的应用;并对推动构建控制片应用体系提出了若干建议。

The“cloud control”paradigm,grounded on geocoded data such as digital orthophoto map(DOM)and digital elevation model(DEM),is gradually maturing for applications in medium and smallscale mapping.However,its essence of obtaining control points from the object space inherently carries errors within the DOM and DEM products,subsequently hindering its applicability in large-scale mapping scenarios.Constructing constraints based on original images with known accurate orientation parameters and adjusted object space tie points represents a theoretically superior cloud control paradigm.This paper proposes developing this image-based cloud control paradigm into a standardized survey and mapping product,termed digital control photo(DCP),aiming to better ensure positioning accuracy while reducing redundant labor and computational power consumption in revisit aerial survey tasks.This paper also introduces the application of DCP in calibration of large-format aerial cameras,geometric positioning of unmanned aerial vehicle images and satellite images,and suggests several recommendations for promoting the establishment of a DCP application system.