Best Practices for Thermal Imagery?

Anyone processing thermal imagery. I am using Flir XT30, 13mm, radiometric on a Matrice 200. I have run a few data sets and not getting anything that is usable. I am seeking any best practices/settings that I should start with. My use of ortho-photos in IR format is for Search and Rescue as well as wildland fire support. Not sure if exif data is even being read properly. Thanks.

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I am also interested in this topic. You can find some best practices for data collection at the Raptor maps website. I have successfully processed a thermal orthomosaic with WebODM, but I have not found a way to have it carry the temperature data thru the process. So at the end it was hard to relate the map to temperature. Would be interested to know if WebODM can handle the temperature values somehow that are embedded in the radiometric jpegs.

This is an interesting topic. Do you have some test images to look at? Feature finding in thermal images is a little different, but usually just works, so I’d be interested in the specifics for this dataset, @Rwhite.

Did you end up getting any images? I can give you some off a lower res 160x120

That is probably too low a resolution to use, unfortunately.

I have been doing a lot of experiments with 160 x 120 and I have got it to around 95% correct, not as great as 640 x 512 but it is possible.

I have the settings on my Linux computer at work and will post this week.

cool! I’ll be experimenting with this really soon. My camera gets mixed 120*160 thermal and 21MP RGB imagery, with the ability to turn the thermal overlay intensity / transparency up or down - I think ODM will find heaps of features in the RGB imagery (usually converted to grayscale) to use.

Should have a working example in early sept, right now at foss4g without my aircraft or my data :smiley:

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by the way - my testing so far has shown that SAR applications for an ANAFI thermal / Mavic dual are a bit sketchy. Humans are more or less thermally invisible under trees if the RPA is a decent distance (eg 30+ m) away. Even when there’s snow cover… More to come!

@bchad thanks for the raptor maps link - those will be super useful.

Change the following on ODM
texturing-skip-global-seam-leveling - Enable
force-gps - Enable
ignore-gsd - Enable
opensfm-depthmap-min-consistent-views - 6
pc-csv - Enable (I want the data thats all)
opensfm-depthmap-method - BRUTE_FORCE

Try that, that seems the best I can get out of it so far.
Aim to be 30m off the objects you are mapping and at a speed of 3m/sec
Do not use MSX on Mavic 2ED just straight IR

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Can you share data sets of thermal images(640 x 512) and color images? Thank you!

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Hello,

Sorry to dig up the post, but I’m wondering if with a Phatom 4 RTK SDK, there are so far some good things in thermal rendering with webodm … winter is coming soon in France (well, let’s go already. 'fall)

All this for thermal monitoring of buildings, buildings and homes.

If not, is there a (not too expensive) camera system that can be adapted on a rtk?

Thank you

Laurent

Thermal is an interesting problem space since a lot of the thermal cameras are like, QCIF resolution or less (160x120) and really low contrast, so they can be challenging to reconstruct with.

I saw the last dji at 640 X 512 pixel, good, but …

Can we adapt an independent camera on the P4 RTK SDK?

WEBODM allows you to test the thermal?

I would do a test drive one of these days one morning, one afternoon and early evening on my roof for comparison …

I don’t know if this will be helpful?

Thank you anyway for the quick response

Laurent

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Not sure if DJI’s firmware lets you add on non-official cameras, and how you’d trigger it reliably. Maybe stick one on with an interval timer like it is 2012 again?

Yes, WebODM does process thermal images, so you’re certainly free to try and/or post your trial set here so others can take a look, as well.

great news for webodm and thermography.

I will do a test in the future and of course I will make the files available so that everyone can give their opinion.

Thank you

Laurent

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Hello,

so, in order not to be mistaken, I have to make a simple orthophoto of the roof.

and manual photos of the facade and I process the photos with webodm by default?

Thank you
Laurent

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Could you clarify what your goal is? I’m not understaning you quite well, I don’t think.

Hello,

I had understood that with a basic orthophoto one could “see” the thermography of a building with special filters like for plants …

I have a hard time understanding it, so you really need a real thermal camera, webodm doesn’t have this “magic” filter?

Thank you

Laurent

There is no magic, unfortunately.

To see thermal, one must have a thermal camera. Regular sensors simply do not capture such long wavelengths.

I thought I had misunderstood or rather interpreted what you had said.

I will see tutorials to adapt, if DJI ok for modification, BUT, I have serious doubts that they will accept

thanks again

Laurent

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