%ostu?image?segment


function?threshold=ostu（filename）;
ff=‘11.jpg‘;


x=imread（ff）;
%figure;
%imshow（x）;
[mn]=size（x）;
N=m*n;
num=zeros（1256）;
p=zeros（1256）;

for?i=1:m
for?j=1:n
num（x（ij）+1）=num（x（ij）+1）+1;
end
end

for?i=0:255;
p（i+1）=num（i+1）/N;
end

totalmean=0;
for?i=0:255;
totalmean=totalmean+i*p（i+1）;
end

maxvar=0;

for?k=0:255
kk=k+1;
zerosth=sum（p（1:kk））;

firsth=0;
for?h=0:k
firsth=firsth+h*p（h+1）;
end

var=totalmean*zerosth-firsth;
var=var*var;
var=var/（zerosth*（1-zerosth）+0.001）;
var=sqrt（var）;
if（var>maxvar）
maxvar=var;
point=k;
end
end
threshold=point;?
for?i=1:108
????????for?j=1:228
??????????????if?x（ij3）	>?160
??????????????????ans1（ij1）=255;
??????????????????ans1（ij2）=255;
??????????????????ans1（ij3）=255;
??????????????else
?????????????????ans1（ij1）=0;
?????????????????ans1（ij2）=0;
?????????????????ans1（ij3）=0;
??????????????end
????????end
end
???????figureimshow（ans1）;?????????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????3719??2010-12-09?21:17??OSTU?matlab\11.JPG

?????文件???????1007??2012-12-11?21:37??OSTU?matlab\ostu.m

?????目錄??????????0??2012-12-11?21:38??OSTU?matlab

-----------?---------??----------?-----??----

?????????????????4726????????????????????3