Request for new thermal image file type (.BMT) support

[ramphastos]

Hi Phil et al.,

I was wondering if you could add functionality for a thermal image file type (not FLIR).  It's a .BMT file from IRsoft.  It looks like a variant of a BMP file since it returns basic meta info, but I was wondering if it was possible to extract the raw pixel data (-b) as is done with the FLIR JPG format?

Attached is an image for your consideration.

Sincerely
Glenn

[Phil Harvey]

Thanks for the sample.

You're right about the BMP format.  Unfortunate because this format doesn't support metadata, and I can find no metadata in this file.  Extracting the raw pixel data should be easy -- just use something like ImageMagick convert to convert from BMP to raw.

BTW, from what model camera is the sample you posted?

- Phil

[ramphastos]

Thanks Phil.  I'll have to look into how to use ImageMagick to convert from BMP to raw, although if someone reading this knows the command to do this, please let me know.

One thing I encountered when trying to import this .bmt file as a BMP is that is saved as 16 bit and some programs refuse to load it. 

The model of the camera is Testo 875i.  I wish we knew how / if the calibration information is saved in the file as well.  Maybe sleuthers on your forum can take a look.  Somehow, i suspect if I obtain the raw data, it may not be radiometric data.

Glenn

[Phil Harvey]

Hi Glenn,

I would be willing to bet that there is no calibration information in this file.

- Phil

[ramphastos]

Hi Phil,

I think you are correct.  My impression is that the raw 16 bit data will correspond to the range setting of the camera (-30C to 100C), without any sophisticated settings for emissivity or environmental compensation.  But then, if opened using IRSoft, it allows for emissivity and reflected environment correction.  I might have to play around with the calculations to see, but will have to get a windows machine to use their software.

Cheers
Glenn

[Phil Harvey]

Try installing Windows using VirtualBox on your current machine.  That is what I am doing now and it works great.  You can download Windows 10 and VirtualBox for free.  The only cost is 15 GB of hard disk space.

- Phil

[ramphastos]

Thanks!  I have Parallels for my Mac.  I can run the PC software, but the fonts are so messed up it's hard to follow.  That's what I meant by another machine.