hi, i need to divide 64x64 binary image into 3x3 overlapping blocks, then in each block ,if center value is 0 leave that block as it is, else that block converted into decimal number ,

plz help me with matlab code

[Walter Roberson]

In one case the result is 3x3 numeric . In the other case the result is... I cannot tell? A 3x3 cell array of 3 digit strings that are the numeric values of the 9 values converted to strings with leading 0?

[kaavya subramani]

8 values is converted to decimal number, in the order(pixel order) idx=[1 4 7 8 9 6 3 2]

[Walter Roberson]

So in one case the output would be a 3x3 numeric matrix, and in the other case it would be the decimal equivalent of putting the 8 bytes together in a single number? So a scalar uint64 result

[Guillaume]

You haven't clarified anything about what form the output should be.

Given the image:

[1 1 1 1
 1 1 0 1
 1 1 1 1]

which would results in two overlapping blocks:

1 1 1               1 1 1
1 1 0               1 0 1
1 1 1               1 1 1

what's the result supposed to be?

out = {[1 1 1;1 1 0;1 1 1], 255}

according to your description, maybe?

[kaavya subramani]

no sir,each 3x3 block has either 0 or single decimal number as output,(i.e) 64x64 will be divided as 3x3 overlapping block,then check each block, if center value is 0, the whole 3x3 is changed to single 0 else it is converted into decimal number in the order of idx

Answer 1

[Guillaume]

m = randi([0 1], 64, 64);  %demo matrix

out = zeros(size(m) - 3);
for col = 1 : size(m, 2) - 3
   for row = 1 : size(m, 1) - 3
      block = m(row:row+2, col:col+2);
      if block(2, 2)
         out(row, col) = polyval(block([1 4 7 8 9 6 3 2]), 2);
      end
   end
end

[kaavya subramani]

Exact answer sir, Thanks a lot, Thank you

Answer 2

[Image Analyst]

Looks like you're describing the local binary pattern, and I'm attaching my demo for that.