I=imread('001011.bmp');
I=imnoise(I,'salt & pepper');
se=strel('arbitrary',[0 1 0;1 1 1; 0 1 0]);
se1=strel('arbitrary',[0 0 0;1 1 0; 0 1 0]);
se2=strel('arbitrary',[0 1 0;0 1 1; 0 0 0]);
se3=strel('arbitrary',[0 1 0;1 1 0; 0 0 0]);
se4=strel('arbitrary',[0 0 0;0 1 1; 0 1 0]);
se5=strel('arbitrary',[1 0 1;0 1 0; 1 0 1]);
U=imdilate(I,se);
U1=imdilate(I,se1);
U2=imdilate(I,se2);
U3=imdilate(I,se3);
U4=imdilate(I,se4);
U5=imdilate(I,se5);
V=imerode(I,se);
V1=imerode(I,se1);
V2=imerode(I,se2);
V3=imerode(I,se3);
V4=imerode(I,se4);
V5=imerode(I,se5);
K=max(abs(U1-U2),abs(U3-U4));
L=min(U-I,U5-I);
M=min(L,K);
N=max(abs(V1-V2),abs(V3-V4));
B=min(I-V,I-V5);
A=min(B,N);
Z=imsubtract(M,A);
%[Z1,y,th]=thresh_md(Z);
%Z1=zishiyingmenxian(Z);
subplot(2,2,1);imshow(I);
subplot(2,2,2);imshow(M);
subplot(2,2,3);imshow(A);
subplot(2,2,4);imshow(Z);