Otsu.m

function [level] = Otsu(I)
 
I2 = im2single(I); 
[m n] = size(I);
 
Err = 1;
T0=(max(max(I2))+min(min(I2)))/2;
 
while Err > 0.0001,
 
u1=0;
u2=0; 
cnt1=0; 
cnt2=0;
 
for i=1:m;
 for j=1:n;

  if I2(i,j)<= T0;
      
u1=u1+I2(i,j);
cnt1=cnt1+1;
 
  else
 
u2=u2+I2(i,j);
cnt2=cnt2+1;
 
  end
 
 end
 
end

 
u1=u1/cnt1;
u2=u2/cnt2;
T=(u1+u2)/2;
 
Err=abs(T-T0);
 
if Err > 0.0001
T0=T; 
end
 
end

level = T0;