How to calculate the mean of an image?
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bh dhouha
on 16 Feb 2015
Commented: Kweku Nkrumah
on 15 Jun 2018
How to calculate the mean of an image? Does the code mean2(img) give the right result?
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Accepted Answer
Image Analyst
on 16 Feb 2015
To calculate the mean of all pixels in the image, without regard to what color channel they came from (if it's a color image), you do
meanIntensity = mean(img(:));
What you did will not do it, as I'm sure you found out.
2 Comments
Image Analyst
on 16 Feb 2015
It could be the same if the image was gray since the blue and green channel would be identical to the red channel. It would also be the same for lots of other cases, like where the green and blue channels are scrambled (spatially rearranged) versions of the red channel since they would have the same pixel values regardless of how they're rearranged.
More Answers (1)
Rashmi.D Jeya kumar
on 8 Jan 2018
meanval = mean2(I) you can get mean value of an image
3 Comments
Image Analyst
on 13 Jun 2018
Why does that mean anything is wrong? Maybe you took a bunch of photos through a microscope and they all have the same mean brightness (or really close to each other). Doesn't seem inherently unusual to me. Why do you think it indicates something is wrong?
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