how can i find max intensity from cell image

i have divided my image into several cells by mat2cell function

if size(R)==[512,512];
else
R =imresize(R,[512,512]);
end

div = [128,128,128,128]; % block s

    if true
      % code
    endize would be 128*128 and division of 
  %images would be 4*4 blocks

Br = mat2cell(R,div,div); % Division of Reference image into Blocks.
Br_r = size(Br,1);
Br_c = size(Br,2);

for i =1: Br_r*Br_c;
    subplot(Br_r,Br_c,i);
  figure(1),imshow(Br{i});
end

but now i wana read the each cell and find if there is any pixel of intensity 255 i dont know how to access the pixels i have applied impixel function but it gives ERROR help me please

Answer 1

[Image Analyst]

if max(max(Br{i})) == 255
  % then do whatever you want to do
end

[Filza Ashraf]

sir, this code is not working it is not detecting the 255 intensity pixels

[Image Analyst]

That's not exactly what you asked. You asked something slightly different and that was that if ANY pixel in the tile was 255 to do something. If you want to get a map (binary image) of where the image is 255 or not, then do this on the original image:

pixels255 = R == 255;