Validation of the positional accuracy of products resulting from the digital processing of UAV images¹

Validação da acurácia posicional dos produtos resultantes do processamento digital de imagens de VANTs

HIGHLIGHTS:

The choice of UAV image processing software should be based on the cost and the accuracy achieved by the product.

Pre-signaled targets for GCP measurements should be visible in their planning, implementation and size, according to a given GSD.

The distribution and quantity of GCPs are fundamental in the altimetric and planimetric analysis of products obtained.

ABSTRACT

Unmanned aerial vehicles (UAVs), also known as drones, are being increasingly applied in different demands and applications, mainly in mapping. Despite the agility and practicality provided by this technology, the image processing software programs currently available on the market are costly and cannot meet teaching/research demands, especially in Brazilian public universities. In this context, this study aimed to evaluate the positional accuracy of products resulting from the digital processing of UAV images using commercial software (Agisoft Metashape) and open-source software (Opendronemap). The planimetric accuracy of the orthophoto mosaic resulting from the two software was not acceptable according to the tolerances defined in the standardization document for planimetric and altimetric accuracy for digital geospatial data, established by the ASPRS (American Society for Photogrammetry and Remote Sensing). Only the altimetric accuracy corresponding to the DEM produced by Opendronemap was satisfactory.

Key words:
remotely piloted aircraft; digital elevation model; orthophoto mosaic