Thermal Image Processing using IR Images

Hi there, I am currently trying to do an image proccessing of an IR images. Is there a way to extract the information regarding hotspots shown in an IR image? Appreciate if anyone can help me regarding this. Most crucial is the temperature information from the hotspots against the blue areas in the image. Thank you.

[Zawir Jasmin]

@Image Analyst Hi sir, I am new to Matlab and in need of an assistance in trying to find out how to extract the temperature measurement from an IR image. Also is there a way for getting hot-spot detection of the image for example the Matlab identify a specific area as high temperature levels?

Answer 1

[Image Analyst]

You'd need either a temperature image, which I think can be exported as long as you aren't using the very cheapest FLIR camera. Or you'd need a colormap so we can convert color into temperature, like in the attached demo.

To mouse around and look at the temperatures in the image you can call impixelinfo() after you display it with imshow().

If you want to locate hot spots based on their temperature, then see my Image Segmentation Tutorial.

Image Analyst's File Exchange

[Zawir Jasmin]

I see, thank you for the quick response sir. Is the image that will be run into this code needs to have a colour bar as shown in your attached thermal_image.png or just an infrared image would suffice? I've tried using with a colour bar image to test out the code but then I got a new colour bar being shown on the left side of the image. Is there any overlapping that might have happened?

[Image Analyst]

Like I said, you either need a thermal image of floating point temperature values in the range of 0-1000 or whatever your temperatures are, or a uint8 or uint16 pseudocolored image with a color bar. You say you had a color bar and got a new one but I don't see any. Not sure what overlapping means. I don't see anything overlapping.

Are you having trouble adapting the code? If so, attach your image with colorbar showing, and your attempt at adapting my code.

[Zawir Jasmin]

After I ran the code given by sir, I noticed my image that turned to grayscale works. However, the colourbar that was cropped is the left side of the image. I am wondering if the image has no colourbar, how do I clear out the colourbar segment and also what if the image has the colourbar but it is on the right side of the image. I tried with the right side colourbar image but the algorithm crops the left side still. Am I missing something to alter this function?

[Image Analyst]

The demo assumes there is a color bar next to the image in a certain location in the image. The image you have shown me so far does not have a colorbar in it. It was just grabbing some part of the image assuming it was a color bar but it isn't. So once you use the proper image you will have to adjust the coordinates from where it takes the colorbar. You can use impixelinfo after you display the image to show the mouse coordinates in the status bar in the lower left of the figure. Attach your image with color bar in it if you need more help. Also, what model of camera are you using? If you're using the very cheapest (like $100) one that clips onto your phone, then you might want to pay a little extra and get the next one up that actually exports the actual temperature values instead of just a pretty picture.