2D landscape mapping - Challenges with edges of rooflines

Hi Guys,

I´m new here and i´m a complete beginner on WebODM.
First i tried a 2D Mapping with my DJI Mavic 2 pro (with the Hasselblad camera) and the IOS APP DJI GS-Pro.

APP Settings:
Flighthight: 40m
Speed: 6,8km/h
Shootingangele: Course Aligned
Capture Mode: Hover & Capture at point
Flightcourse Mode: Inside Mode
Front Overlap: 78%
Side Overlap: 78%
Margin: 0,0m

After the flight i took the 246 pics on WebODM an startet the stiching
Setting in WebODEM:
Erstellt am: 24.2.2022, 13:32:25
Verarbeitungsknoten: node-odm-1 (auto)
Optionen: ignore-gsd: true, dsm: true, pc-quality: high, dem-resolution: 2.0, orthophoto-resolution: 2.0
Average GSD: 0,79 cm
Areal: 25.378,66 m²
Reconstructed Points: 49.792.070

After 2hours of stiching i could Download the Orthophoto in hight quality but i found many quality erros.
Straight lines (rooftopedges) are not straight. The overlaying diddn´t work in that quality what i was thinking that WebODM can do it.
I don´t understand what i did wrong and maybe some of you guys can help me with that problem.

Here the result of my Mapping:

Thanks al lot :slight_smile:

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Let’s work on your parameters a bit:

First, take --ignore-gsd out and never use it :slight_smile: Ever. Seriously, don’t use it. It will just lead to problems later.

I think, given you stopped for each photo, we should have some good success with your dataset.

Let’s try:
--feature-quality ultra
--pc-quality ultra
--pc-filter 0
--orthophoto-resolution 0.5
--dem-resolution 0.5
--min-num-features 32000
--matcher-neighbors 32

If you’re using the latest version, you should have ODM 2.8.0, which has some neat features to improve edges on buildings in orthophotos.


Soooo frist of all thanks for your Answer. :star_struck: :star_struck:
I tried your parameters but after 6 min the Process stopped with the message:
“The program could not process this dataset using the current settings. Check that the images have enough overlap, that there are enough recognizable features and that the images are in focus. You could also try to increase the --min-num-features parameter.The program will now exit.”

The next thing is that i am using WEB ODEM 1.9.11 an i hav eno clue how i can Update it on my windows PC. under tools / Checkout for Updates there ist just a message: "Certificate has expired. Check WebODM Drone Software - OpenDroneMap for Updates . On the Page i can´t find a way how i update WebODM without buying a new Licence.

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Strange that some folks are getting the certificate expiry message! I’ve not been able to reproduce this yet… Hmm.

Please write to [email protected] with your order reciept email which should have your MYSXXXXXX-XXXX-XXXXX number which I can use to generate a new download link for you with.

Strange that it errored out with that message… It should not have. I guess let’s try again under v1.9.12 Build 55 from a newly created task and see what it says/

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I wrote them an email and i hope i will get an answer soon. :slight_smile:

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As soon as the email server syncs and it crosses my inbox, I’ll get you taken care of :slight_smile:

So i tried now your Parameters and the result is as bad as befor.

The Process endet after 14h and 27min. thats way too long for the Quallity what i got.

2422022-orthophoto.pdf (3.8 MB)

What could i do now?

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Hmm, it looks like maybe not enough overlap in certain areas…

You could try forcing --min-num-features to something like 64000 or 128000 to see if it compensates better or not, but it may not help.

A good test would be to select the images around one of your blurred rooftop sections and just process those with the tweaked settings.

Thats the result :exploding_head: :see_no_evil: :rofl:

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Try adding --pc-geometric?

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Hallo Flo, mind sharing the raw dataset with me? I’d like to try this myself on my instance.


How do i do that? :slight_smile:

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Upload to Google Drive, Drone DB, or similar and post a sharing link here.


Here is the Google Drive linnk with all Pictures. 246pics.

and These are the parameters of my DJI GSP on my IPAD


Overlap is not an issue,this roof reconstruction seems indeed strange to me


That´s the result with pc geometric on :see_no_evil: :see_no_evil: :rofl: :rofl:

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10h 8m with these settings produced the below results.

[Grund- und Mittelschule Rottach-Egern - 24/02/2022](javascript:void(0):wink:

246 10:07:48

Created on: 16/03/2022, 09:54:31
Processing Node: node-odm-1 (auto)
Options: auto-boundary: true, dem-resolution: 2, dsm: true, feature-quality: ultra, gps-accuracy: 8, matcher-neighbors: 12, mesh-octree-depth: 12, mesh-size: 300000, orthophoto-resolution: 1, pc-filter: 5, pc-geometric: true, pc-quality: high, pc-rectify: true, resize-to: -1, use-3dmesh: true
Average GSD: 0.84 cm
Area: 25,386.2 m²
Reconstructed Points: 50,735,392

I think it needs some off-nadir imaging for under the eaves details


That looks better. I think we are on the right way :slight_smile: :grin:


I processed the dataset in a different software too and I got the same results. Try re-flying the mission with -85deg camera angles or more. + grid


Hi Gordon,

So I tried your settings and its realy not so bad.

I will try to re-fly the mission with other settings.

I will show you the results…