# How can I find random pixels in an image?

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Faranak on 13 Feb 2014
Commented: Image Analyst on 13 Feb 2014
Hi all, I have a 256*256 pixels image and I want to have 5 randomly pixels in it.how can I do that?
Faranak on 13 Feb 2014
I have some pixels with value more than 1 , I want to find randomly from those pixels. I tried this command : randi(size(imfinal),1,5) but it gives me random number of pixel number. I want exactly the number of i , j of the pixel,and those pixel which their value is more than 1 .

Faranak on 13 Feb 2014
I found the answer,for those who want it:
%%% imfinal is the image
for i=1:256 for j=1:256 if imfinal(i,j)>2 f=imfinal;
end
end
end
%%%% 1800 is the total number of pixels with value more than 1
fo=find(f>20); rndm=randi(1800,1,5); fo2=fo(rndm);
Image Analyst on 13 Feb 2014
That does not do what you asked. The first loop merely assigns the entire image to f. The second part looks at only the first 1800 pixels with a value of more than 20 and picks the linear index of 5 of them.
It doesn't give you "number of i , j of the pixel" and doesn't look at "those pixel which their value is more than 1". But whatever...as long as you're happy.