Sir, I want to find the temperature of a flame image using only Matlab. I am working on the concept to relate flame area with its temperature as as the red component of RGB flame increase with increase with temperature. I have already find out the a

Sir, I want to find the temperature of a flame image using only Matlab. I am working on the concept to relate flame area with its temperature that is the red component of RGB flame increase with increase in temperature. I have already found out the area of flame image. Sir my ques are-

1. Is it possible to find temperature by this approach.
2. How can we define a relation between area and temperature.
3. For this we ought to have database of flame images with knowm temperature. I have 4 of them. Are they sufficient. If not can you suggest an alternativePlease help me.

[Sivakumaran Chandrasekaran]

try for regionprops .. it may help you

Answer 1

[Iain]

The size of a flame doesn't particularly influence the temperature, A very large red flame will always have a lower temperature than a very small blue flame.

That means you're really looking for the colour of the flame. (Google colour temperature to get what I mean)

A colour image will tell you how much red, green and blue (or cyan magenta yellow & black, or HSV values....) is are present in each pixel.

Answer 2

[Image Analyst]

You can give it a shot. You can computer a colormap that relates each color to a 16 bit graylevel. Then use rgb2ind() to convert your color image into a gray level temperature image. Of course the problem you'll have is in color calibrating your image. As you know you can get almost any RGB you want out of your camera by varying the exposure level, saturation, and other settings, plus if you use a consumer camera instead of a machine vision camera it will do all kinds of things automatically to the picture that it thinks will improve the photo, but that you don't want.

[Pranev Gupta]

Thanks for your reply. But the difficulty is that I don't have sufficient facilities for image calibration. That's why I am trying to figure out some alternative approach. Please tell me is this approach possible. The example of images with known temperature that i am using is </matlabcentral/answers/uploaded_files/8913/1299.JPG> The temp of image is given as 1200 C. I am trying to relate the area of these images with already given temp and trying to form some relation between them. But I have only 4 images which are very less for appropriate comparison. Please tell me if some more images of this type can be available. If not, then how we can do flame analysis using only Matlab.

[yingying zhou]

Hello, I don't know whether your problem is resolved. now I am also in facing this serious issue, I need identify fire by extracting the flame, smoke and temperature characteristic .Now in this part of the temperature, it is impossible for me to add a infrared camera, only through the flame color and brightness information to extract temperature, and can't simply use three-color temperature measurement method, because building of this color is wrong, so, if you have solved the flame temperature,can you give me some advices.Thank you very much.

[Image Analyst]

What do you mean by "building of this color is wrong"? Do you mean that the building you're monitoring for fire is also the same color as fire (red, white, yellow, orange)? You forgot to upload your 4 sample pictures so we have no idea what your scenes looks like. Maybe it looks like this orange building on fire:

Is that what you have?

Did you search Vision Bibliography: http://www.visionbib.com/bibliography/contents.html? There are papers there on smoke and fire detection.

If you know in advance that a 3 color RGB camera is not allowable for some (unstated) reason, then are you thinking you'll need a hyperspectral system? Or detectors other than imaging detectors, like smoke or heat detectors?

[Image Analyst]

yingying's "Answer" moved here because it's a comment to me rather than an answer to her original question at the top.

Thank you for the link, I'll go and see.The subject I do is to identify fire by the flame, smoke and temperature characteristic .I haven't find the related information on all of these.And the flame and smoke here is image fire monitoring, a CCD camera is ok. Temperature is what I have to add ,the part of this is difference with others. But most temperature detection is infrared detection or sensor.I think, in the premise of video monitoring, combining with a temperature sensor or the others will be some not practical.In the actual production if it is not feasible.So I just want to extract temperature in color image information .But I only see through the relationship between the chromaticity and temperature, temperature can be detected.As you say, if the color of the building is similar with flame, then it will be a mistake.So now I dont know how to solve this part ,how to extract temperature from color images. I am so sorry that I don't have some pictures of the building fire.Now I just do some processing for the flame and smoke, at present are now in a large collection of pictures related to my topic.Have to say,there is a lot of way to go, ha ha, I will work hard. Thank you for your prompt reply last time.

[Image Analyst]

Yingying, you can't get temperature from a visible image. You can't just look for red, orange, yellow, or white regions. If a woman in an orange shirt walked through your scene, you would not want to sound an alarm and call the fire department. If you try to do this and roll it out, you're going to have a lot of false alarms and a lot of angry people.