Ortho looks 'melted'


#1

I have seen this in 3d models before but not in a 2d overhead ortho. The flight was a simple Drone Deploy based flight of 133 images. The resulting png is here…

The changed defaults are:
Options: dtm: true, min-num-features: 15000, rerun-from: dataset, fast-orthophoto: true, dem-gapfill-steps: 6, dsm: true

I upped the gap fill steps. it did make some areas that were ‘missing’ have something but the lines are still all melted. Curious what other options I could try to get straight lines? I have used webODM on similar flights and don’t know why this one is so bad.

orthoResized

The images are on google drive here:
https://drive.google.com/open?id=1uDg4rCxFqo-_8B74mQAkTSSfYGM_ntAa

And for comparison here is the one free trial of drone deploy made:
ESAMapPlan_Orthomosaic_export_MonJan28061044


#2

--fast-orthophoto can struggle to generate sharp results in urban areas. Try to proces the data without that flag.


#3

I tried that as well. Maybe my flight settings were not good enough for webodm. This ortho is trying to be generated from 78 images, maybe it is not enough?


#4

Good day!
Similar problem: in Pix4D all orthophoto looks great, the WebODM has a wavy image.
The shooting was conducted on DJI Phantom 4 Adv
Options: min-num-features: 15000, rerun-from: dataset, use-3dmesh: true, dtm: true, use-opensfm-dense: true, dem-terrain-type: FlatNonForest, dsm: true, dem-gapfill-steps: 6, opensfm-depthmap-method: BRUTE_FORCE
Options: dem-initial-distance: 0.4, mesh-octree-depth: 12, use-3dmesh: true, dtm: true, dem-resolution: 2.5, orthophoto-resolution: 60, dsm: true, rerun-from: odm_meshing
What settings should be in order to obtain acceptable orthophoto?

Summary

webodm


#5

I read this topic and tried with the following settings:
Options: texturing-nadir-weight: 32, mesh-size: 500000, dsm: true
The result was better, but still the objects are slightly wavy and the buildings have some side walls.
I also noticed that the file generated in Pix4D has a size 300 Mb against 90 Mb in WebODM
How else can you improve the quality of the orthophoto? Processing 85 photos takes 1 hour, I am ready to spend more time, since I do not do commercial activities, but the quality of orthophoto is important to me.
Overall, ODM is an incredibly cool system!

Summary

webodm2


#6

I tried to increase some parameters, orthophoto as a whole became quite good, but the roofs still look very wavy.
Options: mesh-octree-depth: 12, min-num-features: 32000, texturing-nadir-weight: 32, dtm: true, force-ccd: 13.2, mesh-size: 1000000, use-opensfm-dense: true, orthophoto-resolution: 2, dsm: true, opensfm-depthmap-method: BRUTE_FORCE, rerun-from: dataset