www.pudn.com > ridge_extract.rar > extract_m.m, change:2007-05-09,size:1015b

function extract_m 
%---------------------------- 
%自创脊线提取方法 
%---------------------------- 
I=imread('4.bmp'); 
I=im2bw(I); 
D=nlfilter(I,[3 3],@p_direction2);%求点方向图 
% bw=im2bw(I); 
a=coordinate(229,88,I); 
subplot(1,2,1),imshow(a,[]) 
title('原指纹图象') 
% [R,length_right,end_right,i]=forth_follow(78,136,bw,D,1); 
% E=~(double(R).*double(I)); 
% subplot(2,2,2),imshow(E,[]) 
% title('右边脊线') 
% [Q,length_left,end_left,i]=back_follow(78,136,bw,D,1); 
% F1=~(double(Q).*double(I)); 
% R=Q+R; 
% F=~(double(R).*double(I)); 
%  imwrite(F,'test1.bmp'); 
% % J=imread('test1.bmp'); 
% % figure,imshow(J,[]) 
% % subplot(1,3,1),imshow(I) 
% subplot(2,2,3),imshow(F1,[]) 
% title('左边脊线') 
% subplot(2,2,4),imshow(F,[]) 
% title('提取的脊线') 
% length_left,end_left 
% length_right,end_right 
[R,end_left,end_right,length_left,length_right]=r_extract(229,88,I,D); 
E=~(double(R).*double(~I)); 
imwrite(E,'test1.bmp'); 
T=coordinate(229,88,E); 
subplot(1,2,2),imshow(T,[]) 
title('提取出来的脊线')