# How can I find the x and y coordinate of the first pixel of an image .

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Anushka on 7 Feb 2015
Commented: Anushka on 7 Feb 2015
I have divided an image of size 256*256 into 64 blocks of size 32*32.Can any one suggest any method to find the (x,y) coordinates of the first pixels of each block.Each block was saved as Block(:,:,i),were i denotes the block number,ie i can be any number from 1 to 64.

Youssef Khmou on 7 Feb 2015
Edited: Youssef Khmou on 7 Feb 2015
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
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Anushka on 7 Feb 2015
Thank you very much sir it worked properly.