Artefatos do Drone2Map no mosaico orto

Question

Eu criei um mosaico orto no D2M. Primeiro com as configurações padrão e GSD 1. Ele contém artefatos ao redor de todo o mosaico como mostrado abaixo.<\/P> <\/span><\/P>Depois de ler alguns posts nesta comunidade, eu alterei as configurações, como marcar "rolling shutter optimization", mudar o inicial para full e marcar "use geometry verified matching". Isso produz ainda mais artefatos e move completamente o orto por algumas centenas de metros.<\/P>Usando as configurações padrão, a qualidade geral é OK, exceto por esses artefatos. Por favor, aconselhe como esses problemas podem ser evitados.<\/P>Atenciosamente<\/P>

DerrickWestoby · Answer

You really want to be flying with 70%+ overlap with SfM.   Keep in mind that this is based off the drone's altitude above ground level and an image footprint projected into the ground.  If you're flying over tall buildings, especially at low (<200ft) altitudes, the overlap in those areas is going to be insufficient.  You may have 70%/70% overlap at ground level, but 50%/50% on the building roof.

FrankOuyang · Answer

As suggested by @DanPatterson, capturing more images using higher overlap ratio will help reduce the artifacts, such as increase it from 60% to 80% or 90%. This will increase processing time and the output point cloud size but it can significantly improve the quality of the output.

Another thing to consider, from my experience, is try to fly the UAV at the solar noon when the shadow is minimized. By doing so, object/area of interest will have the best illumination which helps the photogrammetry algorithms identify objects and reconstruct them and eventually, reduce the chance of having artifacts.

DanPatterson · Answer

There other related links to the right of your post, for example,

Solved: Drone2Map imagery quality - Esri Community

which suggests "overlaps" setting