Similar Issues to others but using a Zenmuse H20T camera

[ben5050]

Hi, I have read the other issues (#1 and #2) posted and it seems my issue is very similar. Unfortunately, for me, I have no programming knowledge. I'm trying to convert rjpg images taken using a Zenmuse H20T (from a UAV) to tiff. The final goal is to process them in Metashape. Metashape only takes tiff.

When I run the IRimage process tool from Fiji plugins, i get the following macro error - Index(5) out of 0-4 range in line 360 columns = split ( rows [j <]>,".");

I used the exiftool on a image and it was extactly the same as shown in Issue 1 -IRimage process RJEG from different sensors #1 18/01/2022.

Attached are some of my photos from the Zenmuse H20t ( zip file).

Would you be able to help me?

Debug.csv

DJI_20230603165846_0002_T.zip

[gpereyrairujo]

Hi Ben,

Thanks for reporting this issue and for the images. The error you are getting is because the images from DJI thermal cameras are encoded differently from hand-held FLIR cameras or UAV cameras such as the Vue Pro R, and the current IRimage code is not able to process them.

Fortunately, I think I might be able to extend the code, using a software released by DJI some time ago. UAV thermal cameras are increasingly popular now, and I think it would be useful to be able to batch process them using IRimage. I will give it a try in the following days, and I will let you know if it works

Gustavo

[ben5050]

Hi Gustavo, That's would be great if you could have a look. Batch processing would be fanastic as I have about 600 hundred images. Kind regards Ben

[gpereyrairujo]

Hi Ben,

I have been able to convert your images to TIFF format. I am attaching the results.

I also included another step of copying the GPS data, which can be useful for processing with photogrammetry software. I do not have access to Metashape, but I can try with OpenDroneMap to check if it is possible to build an orthomosaic. Unfortunately, with only 2 images I'm not able to run the reconstruction, so it would be great if you could share some more images (around 10 images would be ok, with forward- and side-overlap) for me to check everything before I publish the new plugin.

Kind regards, Gustavo

tiff.zip

[ben5050]

Hi Gustavo, That is great. I will email you a link to a full data set. It is many photos but should give you a good ortho result. Kind Regards Ben

[gpereyrairujo]

Hi Ben, Thanks for the images! I was able to process them with IRimage and then with OpenDroneMap to obtain a georeferenced orthomosaic with temperature values:

I have now added a new version of the plugin (IRimage-UAV) specifically for processing thermal images from DJI drones (since the file format is different). You can find it in the IRimage repository (https://github.com/gpereyrairujo/IRimage), and the installation is similar to what you did with the original version

I hope it works ok for you. Let me know if you find any problems

Kind regards, Gustavo

[ben5050]

Hi Gustavo, Thanks very much for your help. On the testing I have done so far, this works perfectly when using the H20T images. Great stuff! Cheers Ben

[ben5050]

Hi Gustavo, Hope you are well,

The software is working very well.

I have a question and was hoping you could answer it -

My UAV flights are generally at about 50 metres above ground level (AGL) but could be anywhere from 20m to 100m AGL. When processing the H20T images with ImageJ we are asked to enter the Reflected Temp, Object EMS, Air Humidity and Object Distance. The maximum allowable object distance that can be entered is 25m. So even though my Obj dist is generally about 50m, I can only enter 25m. Could the software be changed to allow a greater object distance? Ideally it would allow any distance and not have a maximum.

Also Relative Humidity has a minimum of 20%. Could this be changed to 0%?

Any help appreciated, thanks again for a great program.

Kind Regards, Ben

input data snapshot for Gustavo Pereyrairujo.pdf

[ben5050]

Hi Gustavo,

Hope you are well.

I posted two questions to you on your GitHub page . If you have a moment could you have a look? https://github.com/gpereyrairujo/IRimage/issues

Kind regards, Ben

Sent from Gmail Mobile

On Thu, 15 Jun 2023 at 3:23 am, Gustavo Pereyra Irujo < @.***> wrote:

Hi Ben, Thanks for the images! I was able to process them with IRimage and then with OpenDroneMap to obtain a georeferenced orthomosaic with temperature values:

[image: imagen] https://user-images.githubusercontent.com/8480839/245881973-efcdc2f8-3e03-4e5f-a969-3f6b4907773a.png

I have now added a new version of the plugin (IRimage-UAV) specifically for processing thermal images from DJI drones (since the file format is different). You can find it in the IRimage repository ( https://github.com/gpereyrairujo/IRimage), and the installation is similar to what you did with the original version

I hope it works ok for you. Let me know if you find any problems

Kind regards, Gustavo

— Reply to this email directly, view it on GitHub https://github.com/gpereyrairujo/IRimage/issues/4#issuecomment-1591699992, or unsubscribe https://github.com/notifications/unsubscribe-auth/AVRMNCE7IIHJSBQQTSVFCULXLHXQPANCNFSM6AAAAAAYZXJNKE . You are receiving this because you authored the thread.Message ID: @.***>

[gpereyrairujo]

Hi Ben, sorry for the delayed response, I was travelling. Those limits are the maximum and minimum values allowed for each variable by the DJI Thermal SDK. Unfortunately, I have currently no way to obtain the camera parameters from the images in most DJI cameras, and therefore it is not possible to use the "full" algorithm, and I had to resort to the closed-source DJI SDK :(

[PrashantMakwana]

Hello Gustavo, I hope you are doing well.

I have thermal images captured using a DJI Zenmuse H20T camera in JPEG format. My goal is to create an orthomosaic of these images while also georeferencing them and determining the temperatures of each pixel. I've been attempting to retrieve temperature values for each pixel within the orthomosaic image.

I initially tried orthomosaicking in Pix4D, but I have doubts about its accuracy. According to Pix4D's website, it appears that Pix4D currently cannot process images captured by the Zenmuse H20T camera. To address this, it seems I need to use third-party software to convert the thermal images to TIFF format, which includes the temperature values.

You previously provided guidance on how to perform this conversion of thermal images to TIFF and subsequent orthomosaicking and georeferencing processes. My ultimate objective is to open the orthomosaic image in ArcGIS Pro while retaining the temperature values for each pixel.

kind regard Prashant

[OwenC1979]

Thanks for this tool. I've had fantastic success incorporating this into a workflow for producing orthorectified thermal mosaics with a DJI Magic 3T, Agisoft Metashape, and QGIS. Nice work!

[petrdrn]

Hi Gustavo,

Extenting this thread since I'm also working with DJI images.

Your tool works very well and I was able to convert my images captured with DJI Mavic 3T from rjpeg to tif. My goal is to create a thermal orthomosaic using Agisoft metashape.

When I upload the images to Metashape I notice that the coordinates have somehow changed. Below you can see coordinates from original rjpeg:s and converted tiffs. Do you have any idea how to fix this issue?