:ôԶȡͼֵ.

ʽ:
ImageAutoThreshold(img,level)
ImageAutoThreshold(img)

img:Ϊݾ
level:Ϊʱ,ʾڴ˾ѡѵһֵΪֵ;levelΪֵʱ,ʱֻΪ,ʾimgݷֳlevelȼ,ֵڸȼѡֵ,ĬΪ244

˵:ɹһôɷõֵ

ԭ:
1ֵΪt,tlevel
2СڵtԪimgռΪw0ֵΪu0;tԪimgռΪw1ֵΪu1
3Ѱһg=w0*w1*(u0-u1)^2Ӧt,Ϊֵ

PS:ΪûimgԪصĴС,ʺϸݲɼʱҪͨȡһֵĺ.ͼֵ,ʹô˺ԺܷлҶ(һָĽĴ)ֵȷ.

:
//ֱִ´,ԿµĽ

a={ImageImport<\ImageImport>}();//ͼƬ
a={ImageToGray<\ImageToGray>}(a);//ȡҶͼ
[r,g,b,a]={ImageToArgb<\ImageToArgb>}(a);//ȡɫ
lev=ImageAutoThreshold(r);//ȡ˷ֵ
r = {ImageToBinary<\ImageToBinary>}(r,lev);//ʹôֵѻҶͼֵ
d = {ImageFromArgb<\ImageFromArgb>}(r,r,r,a);
{ImageExport<\ImageExport>}(d)//ͼƬ

//ͼ
{<http://img0.ph.126.net/JBW2No2IbcjR6hhvsXd9FA==/1802284275978791943.jpg>}

//ɵõµͼ
{<http://img2.ph.126.net/B0QNqARQ4vfLCYHiQSI0_A==/6619205134746655175.png>}