GIM International | Year: 2010
The Quebec Ministry of Agriculture (MAPAQ) in Canada has developed its Prime-Vert program to help farmers reduce the impact of pollution caused during food production. The program assists farmers in assessing potential erosion issues and supports them in establishing measures to limit environmental damage. Such measures include construction of grassed waterways or intersecting drains for the safe disposal of runoff water, or modification of terrain slope to redirect surface water. The assessment of erosion in farming areas requires indicators based on terrain elevation. MAPAQ personnel collect such information on site. Aerial images, to which MAPAQ had access, were identified as a good alternative to land surveying and Lidar for providing high-quality elevation data. Having invested less than 10% of their initial data acquisition costs, MAPAQ personnel were able to use this new photogrammetric software suite to generate high-quality DSMs with 2m GSD and 20cm vertical accuracy on each grid post.
Rotenberg K.,SimActive |
Simard L.,SimActive |
GEO: connexion | Year: 2013
The article explores the software solutions necessary in overcoming the challenges of UAV photogrammetry. The data collected by UAVs are therefore very low quality in comparison with survey grade camera systems. The sensors are poorly calibrated and there is often no orientation data because of the absence of an IMU (attitude sensor). Thus, it is difficult to extract precise geospatial data products such as digital surface models (DSM), digital terrain models (DTM) and orthomosaics from such low quality data. But since there are multiple operational advantages associated with UAVs, such as quick deployment and associated low costs, there is a huge demand for software solutions that would allow rapid and precise photogrammetry. On the one hand, traditional photogrammetry software tools are designed for processing a small number of large-format images. They have trouble handling a very large number of images, even if those images are small. Traditional photogrammetry software expects high accuracy data if it is to derive high-quality results.