How to detect the temperature degrees from a thermal image taken by Therm App camera ?

Hello,

I would like to ask about how can i use matlab to detect the temperature out from a thermal image taken by themapp camera. I converted the thermal image to greyscaled image, plus i applied Adaptive thresholding for it. Looking for help.

Thanks

Answer 1

[Image Analyst]

"I converted the thermal image to greyscaled image" <= well there's your problem. DON'T DO THAT. Keep the thermal image as it is, with units of temperature as given by your instrument. DO NOT convert units to gray levels. Keep your thermal image unconverted and you'll have the proper units or Kelvin or Celcius or whatever.

[Mohanad Ahmed]

Thanks for replying Image Analyst, i was waiting for your reply.

Yea okai i have the thermal image, its for detecting high temperature spots. But how can i detect the temperature of this thermal image. I mean using matlab, can i create like a color bar depending on the temperature range of the camera ? how ?

[Image Analyst]

Use colormap() and colorbar():

colormap(hot(256)); % Or whatever color map you want.
colorbar;

[Mohanad Ahmed]

Would like to ask a question, how can i extract the foot image from the full image ? i mean removing background and having only the foot

[Image Analyst]

You can use image analysis. Like perhaps simple thresholding will be good enough, if you're lucky.

[Jai Sri]

How to detect the temperature in thermal image using ROI function?

[Image Analyst]

Which ROI function? There are several of them? But anyway, the temperature MIGHT be the pixel value. If it's not, and it's simply a gray level, then you'll have to somehow get a function that turns gray levels into temperatures, like the attached demo.

[Jai Sri]

But error in the line Histogram (thermalImage,'Normalizaton','probability'); How i solve this problem?

[Image Analyst]

Change "Histogram" to "histogram" and 'Normalizaton' to 'Normalization'. Also, what version are you using? histogram() was introduced in R2014b. Plus, you never told me the error for some reason, and my crystal ball is in the shop for repairs.