making picture through imshow

I want to make size 256x256 picture

A = ones(16);
num = 1;
for i = 1:floor(length(A)/2)
    num = 1-num;
    A(1+i:end-i, 1+i:end-i) = num;
end

it doesn't work how I want to make

it there any different way?

[relamanma]

A=ones(16);

B=zeros(16);

C=[B B B B B B B B B B B B B B B B];

D=[B A A A A A A A A A A A A A A B];

E=[B A B B B B B B B B B B B B A B];

F=[B A B A A A A A A A A A A B A B];

G=[C;D;E;F;F;F;F;F;F;F;F;F;F;E;D;C];

imshow(G)

except this path

[KSSV]

You want to make picture as attached?

[relamanma]

If you have time to hel...p !!

Answer 1

[Walter Roberson]

Z = logical(256,256);
Z([1:16,end-15:end], :) = true;
Z(:, [1:16,end-15:end]) = true;

You should be able to continue from there.

[relamanma]

thank you~