Hi Guys,


Sorry for the dumb question, it's been a long week.

So, I am trying to collect thermal data for a research project. How do I download the radiometric video data?
I have the _S and _T files for my trial flights, but neither of these are able to be opened in DJI Analysis Tool 3 or are able to be converted into JPGs keeping the thermal data.


Have I misundertood the M30T's capabilities, or am I just being an idiot?

Thanks for the help.

Hi,

From the videos you probably won't do anything.  It's just pretty, there are lots of colors.  From the JPGs you can already put DJI analysis tool in the trash, you will have to scale your images before using them.  In the metadata of the image there is the temperature range in degrees Celsius, and the image is 8 bit, 0-255.  You have to do the conversion if you want the value of each pixel.  There are paid programs that do this.  There is also a DJI SDK for Windows.  The M30T and DJI thermal cameras in general are not really suitable for research work.

LV_Forestry Posted at 1-4 23:10
Hi,

From the videos you probably won't do anything.  It's just pretty, there are lots of colors.  From the JPGs you can already put DJI analysis tool in the trash, you will have to scale your images before using them.  In the metadata of the image there is the temperature range in degrees Celsius, and the image is 8 bit, 0-255.  You have to do the conversion if you want the value of each pixel.  There are paid programs that do this.  There is also a DJI SDK for Windows.  The M30T and DJI thermal cameras in general are not really suitable for research work.

Glad to know it isn't me being completely stupid... kind of!
Unfortunately, this is the only drone I have access to with an IR camera on. Shame it isn't great...

Going forward, what packages would you recommend?
Secondly, would you be able to point me in the direction of any paid programs so I can have a look as it sounds like this is the route I am going to have to take.

Thanks for your help!

Chaz1308 Posted at 1-4 23:13
Glad to know it isn't me being completely stupid... kind of!
Unfortunately, this is the only drone I have access to with an IR camera on. Shame it isn't great...

https://www.dji.com/lv/downloads/softwares/dji-thermal-sdk
https://aetha.global/product/thermoconverter/

This command is appropriate
./dji_irp.exe -s ../../../../dataset/H20T/DJI_0001_R.JPG -a measure -o measure_float.raw --measurefmt float32

Chaz1308 Posted at 1-4 23:13
Glad to know it isn't me being completely stupid... kind of!
Unfortunately, this is the only drone I have access to with an IR camera on. Shame it isn't great...

Hi Chaz1308,

I encountered the same issue. For short researches I am using screen recording to get temperature indicators in the video.

But it is not fully useable, see my post: thermal indicator when in split screen
(https://forum.dji.com/forum.php?mod=viewthread&tid=281911)

For longer actions it is absolutely unuseable.
The Microsoft Windows programs I can not use, only Linux is available.

djiuser_zyklide Posted at 1-7 04:09
Hi Chaz1308,

I encountered the same issue. For short researches I am using screen recording to get temperature indicators in the video.

This could be useful :

https://github.com/radekszostak/DJI-Thermal-Decoder

LV_Forestry Posted at 1-7 09:19
This could be useful :

https://github.com/radekszostak/DJI-Thermal-Decoder

Hi LV_Forestry,

thank you for your advice.

I found this too, but I am doing all the work on the rc, maybe for trial I test it on a vitual linux machine on the device.
I do not want additional devices, only the connected monitors, mouse and keyboard.

So I have to spend more time.

By the way,
so annoying, I had today a helicopter landing and take off.
Forgot to start screen recording and now the high / low temperature indicators I saw on the screen are gone.

I will to try to remember to activate for next recordings, until it is fixed.

Hot spots are visible, but no temperature, should be out of the box.

djiuser_zyklide Posted at 1-7 10:34
Hot spots are visible, but no temperature, should be out of the box.
[view_image]
[view_image]

I repeat here what i wrote on another thread :
Try using GDAL Translate, look up the temperature range in the EXIF, then convert from 8 bit to Float32.  Then you can use the raster tools as you wish.  I just tried it works wonderfully.

LV_Forestry Posted at 1-7 13:58
I repeat here what i wrote on another thread :
Try using GDAL Translate, look up the temperature range in the EXIF, then convert from 8 bit to Float32.  Then you can use the raster tools as you wish.  I just tried it works wonderfully.

Hi LV_Forestry,
I am a little bit confused, or did I miss something?
How does position data affect thermal view?

Please provide a link to your mentioned post and maybe sources.

Thank you in advance!

WYSIWYG is all I want.

djiuser_zyklide Posted at 1-7 14:59
Hi LV_Forestry,
I am a little bit confused, or did I miss something?
How does position data affect thermal view?

"WYSIWYG", that's what I'm offering.

I'm even more confused than you, I didn't mention position data.

The method that I propose allows you to convert images to TIFF formats with the value of each pixel in degrees Celsius, instead of an unusable RGB value.

This is the request of the OP, and thermal camera users in general.

I understand that you want to zoom in to acquire temperatures. In real time it will be complicated because the helicopter is moving, and the resolution of the thermal camera does not allow this to be done in a right way. Otherwise you have to be very close.

This is why I suggest that you take R-JPEG photos, not screenshots, then convert them, in post process, so that you can use them in software that allows zooming and pixel-by-pixel analysis, but also zonal.

LV_Forestry Posted at 1-8 01:05
"WYSIWYG", that's what I'm offering.

I'm even more confused than you, I didn't mention position data.

Hi LV_Forestry,

I am familiar with post-processing captured data according images, but converting a sequence of pictures into a video would take a lot of time, when a deep analysis is not needed.

In some situations it is sufficient to display the temperature as in the live view.

djiuser_zyklide Posted at 1-8 05:27
Hi LV_Forestry,

I am familiar with post-processing captured data according images, but converting a sequence of pictures into a video would take a lot of time, when a deep analysis is not needed.

There is like a discrepancy.  
As I didn't talk about position data, I didn't talk about video.  
I'm talking about thermal photography.

LV_Forestry Posted at 1-8 06:08
There is like a discrepancy.  
As I didn't talk about position data, I didn't talk about video.  
I'm talking about thermal photography.

So let us wait for the next firmware update or upgrade to deal with video.

Thank you for your advices.



(The pictures are screenshots of the video.)

LV_Forestry Posted at 1-4 23:10
Hi,

From the videos you probably won't do anything.  It's just pretty, there are lots of colors.  From the JPGs you can already put DJI analysis tool in the trash, you will have to scale your images before using them.  In the metadata of the image there is the temperature range in degrees Celsius, and the image is 8 bit, 0-255.  You have to do the conversion if you want the value of each pixel.  There are paid programs that do this.  There is also a DJI SDK for Windows.  The M30T and DJI thermal cameras in general are not really suitable for research work.

Hi LV_Forestry,

I misunderstood you.

Would be nice to record all the data to analyze afterwards.

Also positions and viewing angles of each frame in a video.

Maybe it wiil be supported with some GDAL script to create a video automatically.

There is a thread about recording telemetry:
https://forum.dji.com/forum.php?mod=viewthread&tid=278923

So it sounds like you guys are saying the M30T may not be worth the hassle and just stick to the flir 640T on another plateform?