function edg = edgy(pict)
test = double(pict);
size(pict)
sx = [-1 0 1; -2 0 2; -1 0 1];
sy = [ 1 2 1; 0 0 0; -1 -2 -1];
edg = zeros((size(test,1)-2),(size(test,2)-2));
for ii = 2:(size(test,1)-1)
for jj = 2:(size(test,2)-1)
A = test((ii-1):(ii+1),(jj-1):(jj+1));
x = sx.*A;
x_sum = sum(sum(x));
y = sy.*A;
y_sum = sum(sum(y));
M = sqrt(x_sum^2 + y_sum^2);
edg(ii-1,jj-1) = M;
end
end
edg = uint8(edg);
end



