How can I create a small cell 500*500 pixel in one satellite image?

I have a Landsat 8 satellite image with size of [7761, 7601].

I want to create a small cell with 500*500 pixel and calculate NDVI index for each cell and move to the next cell by using for loop.

I am a beginer . Please help!

Thanks a lot!

[Oanh La]

This is my code. Please help me!

Thanks a lot!

tiles=zeros(500,500);

for m=1:(size(layerstacking_TOA_Ref,1)/500)-1

for n=1:(size(layerstacking_TOA_Ref,2)/500)-1

r=500*m;

c=500*n;

if m==1&&n==1

tiles(i,j)= layerstacking_TOA_Ref(1:r,1:c);

elseif m==1&&n~=1

tiles(i,j)= layerstacking_TOA_Ref(1:r,c+1:c+500);

elseif m~=1&&n==1

tiles(i,j)= layerstacking_TOA_Ref(r+1:r+500,1:c);

else

tiles(i,j)= layerstacking_TOA_Ref(r+1:r+500,c+1:c+500);

end

end

end

NDVI = zeros(size(tiles,1),size(tiles,2));

y = zeros(8);

for i=1:size(tiles,1)

for j=1:size(tiles,2)

for num1=1:16

for num2=1:16

for b=1:8 % bands of the image

y(b)= tiles{num1,num2}(i,j,b);

NDVI(i,j) = (y(5)-y(4))./ (y(5)+y(4));

end

end

end

end

end

Answer 1

[KSSV]

Refer this....it should help you:

https://www.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#answer_286773