How To Find the Temperature of the Image

I got a job to look for the Temperature of the Image (i take it from infrared camera). example picture:

http://1.bp.blogspot.com/-NCobHALZIY8/TrKmXY1uWII/AAAAAAAABIM/jbf2sw87yA0/s1600/2011_09_11_17_31_53+20.jpg

How to know the temperature distribution using matlab? (especially at the end of the chisel)

I really need your ideas regarding this matter since I am new for this toolbox. Thanks

[Ashish Uthama]

Haris, more info might help get a better answer: info on your image acquisition method, like the camera used, the object/s being imaged, the distance, possibility of modifying the setup (i.e do you get just get the image, or do you have the freedom to change the way the image is captured)

Answer 1

[Walter Roberson]

This cannot be done without additional information that maps color values to temperatures.

With just the picture alone, we do not know what the highest temperature was, what the lowest temperature was, and we do not know whether the sensors were linear or log or some other transfer function. And just given the picture alone, we do not know whether the image is pure emission or if there was some illumination and whether the potential illumination was even.

With just the picture alone, we do not know which part is the chisel, and which part is the end of the chisel. (I was getting this wrong myself until a few seconds ago... I think.)

Calibration information is required in order to proceed.

[haris]

The picture is the process of lathe on magnesium material. This picture comes from a video of an infrared camera, I convert the video to a form of multiple photos (video to jpg).

The following details:

http://harismahrudi.us/wp-content/uploads/2012/01/2011_09_11_17_31_53-20.jpg

Sorry i did not know the highest temperature and lowest temperature, but when the lathe we measure temperature using a thermocouple that showed approximately 60 degrees Celsius (thermocouple on the chisel)

Can I convert it to forms like the following picture?

http://climate.uvic.ca/climate-lab/front_page_pics/temperature.lrg.jpeg

Thank you for your response..

[Walter Roberson]

We need the calibration information.

The data that comes from the camera: is it 3-channel (RGB) or is it monochrome (2D)?

Try taking one of the .jpg, rgb2gray() it, imagesc() the result, and then colormap(heat). imagesc() will not be usable over the long term (you need absolute intensity to temperature calibration whereas imagesc() would work on relative intensity), but it would give you an idea of whether you are on the right track or not.

[shima amirifard]

hi i have my lepton camera temp. range and want to determine a particular point temp from the captured thermal image, would u plz help me on codes tnx so much

[Walter Roberson]

shima amirifard, as discussed above, you need to know the transfer function -- how the color (or intensity) varies with temperature.