Artefakty Drone2Map v ortomozaice

Question

Vytvořil jsem ortomozaiku v D2M. Nejprve s výchozím nastavením a GSD 1. Obsahuje artefakty po celém okolí mozaiky, jak je uvedeno níže.<\/P> <\/span><\/P>Po přečtení několika příspěvků v této komunitě jsem změnil nastavení, například zaškrtnul "rolling shutter optimization", změnil initial na full a zaškrtnul "use geometry verified matching". To způsobilo ještě více artefaktů a ortomozaika se posunula o několik set metrů.<\/P>Při použití výchozího nastavení je celková kvalita v pořádku kromě těchto artefaktů. Prosím o radu, jak lze těmto problémům předejít.<\/P>S pozdravem<\/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