How can i get the percent of pixel for a certain color in C# ?

Question

My extended question is, how can you, count how much x-color has an image? I mean, i have a real-time image from an infrared camera,and when the temperature passes a certain value,the pixels in that area become red for example. How can i find out,how much (in percent) does the red area is,from the entire image (384x288)?

Answer 1

You can divide the image in squares, then calculate the dominant color for each one, for example http://chironexsoftware.com/blog/?p=60.

Don't do it directly on the Bitmap/Image class if you want to have acceptable perfomances.

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Matteo Migliore

Bloghttp://blogs.ugidotnet.org/matteomigliore
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Answer 2

Your example is good but can't help me. Let me tell you more... My Infrared Camera image is broadcasted directly into a panel, in my code i dont have any bitmap, image, because they were used in an other library class. I just call that class and get the image in the panel. I now know if in some point of the image there is high temperature, and at that point an alarm will start. i just want to control the alarm meaning : i want the alarm to start only when there's a considerable number of pixels with that high temperature , i don't want to start the alarm when (absurdly speaking) there's a 50 degrees fly entering the room, only when there is a big object, or a person. For that i need to know in percentual how much of the image does the high temperature pixels ocupy ?

Answer 3

It's quite clear, on which object do you want to work?

If you haven't a Bitmap, which is the object that you can analyze?

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Matteo Migliore

Bloghttp://blogs.ugidotnet.org/matteomigliore
Twitterhttp://twitter.com/matteomigliore
CodePlex

http://hyperionsdk.codeplex.com http://sample.codeplex.com

Answer 4

I have a function like this :  if( currentEngine.Name=="Infrared") IR_Video.Handle.ToString(); IR_Video is a panel . 

Answer 5

Hi Alexandlu,

Frankly speaking, I am not sure how the Type store image. Could you please let me know some details about this type?

Have a nice day.

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Alexander Sun [MSFT]
MSDN Community Support | Feedback to us

Answer 6

I solved it with a little help, in Visual C++. What do i have to do to close the topic?  Thank you for the interest given, at least at this topic some1 answered me. 

Answer 7

Hi Alexandlu,

I am glad to know your problem is resolved. You can post some core code here or describe the solution, which will be appreciated.

Have a nice day.

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Alexander Sun [MSFT]
MSDN Community Support | Feedback to us