I think you mean the intensity of the first element in each block, otherwise, you already know the coordinates :
firs block : (1,1);
second block : (1,33); % moving in right direction
eighth block : (1,32*7+1);
last block : (225,225);
If you start from left top and count horizontally, the fast way to get the coordinates is :
l=1:32:256;
n=length(l); % equals 8 blocks
FirstPositionBlock=zeros(n,2);
ind=1;
for x=1:n
for y=1:n
FirstPositionBlock(ind,:)=[l(x),l(y)];
ind=ind+1;
end
end
