www.pudn.com > ridge_extract.rar > p_direction2.m, change:2007-05-08,size:316b

function pd=p_direction2(A) 
%3X3邻域 
F=zeros(1,4); 
a=double(A); 
%1方向  
F(1)=abs(a(2,2)-a(2,1))+abs(a(2,2)-a(2,3)); 
%2方向  
F(2)=abs(a(2,2)-a(1,3))+abs(a(2,2)-a(3,1)); 
%3方向  
F(3)=abs(a(2,2)-a(1,2))+abs(a(2,2)-a(3,2)); 
%4方向  
F(4)=abs(a(2,2)-a(1,1))+abs(a(2,2)-a(3,3)); 
[x,index]=sort(F); 
pd=index(1);