Eliminate the pixel that have a lower intensity?

I read the immage in this way:

m=max(Imm,[],'all');
%Threshold
thr=10;

for i=1:2048
    for j=1:2448       
        if Imm(i,j)>(m-thr)
           pos(k,1:2)=[i,j];
           k=k+1;
        end
    end
end

"Pos" contain all the pixel of my intrest, now i want to elimintate all the coordinates of the pixel that have intensity lower than a value

Answer 1

[Ameer Hamza]

You don't need a for-loop for this

m=max(Imm,[],'all');
%Threshold
thr=10;

[r,c] = find(Imm>(m-thr))
pos = [r c];

By elimination, if you mean to set them to zero, then try this

m=max(Imm,[],'all');
%Threshold
thr=10;

Imm(Imm<(m-thr)) = 0;

[valerio auricchio]

iI really liked the solution for find the points, but after that i find the point i want to read another immage and with the point obtainad from the previus immage have an intensity lower than a value. I do not want to set them to zero

[Ameer Hamza]

Do you just want to read the pixels from second image? Is the second image of same size? Try this

m=max(Imm,[],'all');
%Threshold
thr=10;

idx = Imm>(m-thr)

Imm2; % 2nd image
pxls = Imm2(idx);

[valerio auricchio]

the fact is that after i find the point in fist immage and save them in this way:

m=max(Imm,[],'all');
%Threshold
thr=10;
[r,c] = find(Imm>(m-thr))
pos = [r c];

I want to use this point in the second immage and want to eliminate the point saved in "pos" where the intensity is lower than a value

[Ameer Hamza]

I didn't understand the question. Can you take 2 small 3x3 matrices and show with an example of what you want?