How to make nested loop from 8x8 block for image size 512x512?

i have an image with size 512x512, then i make a 8x8 block so there is 4096 block, i want to calculate variance function in each block, how to make a for loop kx so one block kx will calculate and move again in second block then calculate again so it will calculate all 4096 block, i'm stuck just only one row inside of first block, can someone help me? thank u

 i []; j[];
 for k=1:4096
    kx=(x{k});% extracting block into kx for processing
         for i = 1:8
              for j = 1:8
                 Variance = var(kx);
              end
         end
 end

[Adam]

I would have thought one of

doc blockproc
doc nlfilter

would be able to do this if you have the image processing toolbox

[DhaniAri]

thank u for your help, i will try

Answer 1

[KSSV]

This will help you:

https://in.mathworks.com/matlabcentral/answers/362262-i-have-a-32-32-matrix-i-want-to-take-mean-of-each-4-4-so-that-the-matrix-is-reduced-to-8-8-array

[DhaniAri]

thanks KSSV for your help

[KSSV]

Thanks is accepting the answer.....!