sigptst1.m

图像对齐（inage registration）工具箱

function [HGF,Cex,HM,ANG,POS1,POS2]=sigptst1(X,f1,k,f2,kr)
% SIGPTS2 - find significant points in an image, step 1 (preprocess)
% 				[HGF,C,HM,ANG,POS1,POS2]=sigptst1(X,f1,k,f2,kr) 
%
% X: input image
% f1: filter to apply to X
% k: half size of square to fit locally
% f2: 1D filter to apply to per/funs for sign changes count
% kr: size of square for changes, may be any
% HGF: how good is the fit
% C: averages over squares size 2k+1
% HM: number of sign changes around squares
% ANG: angle between edges (index length)
% POS1,POS2: source for ANG
%
% Copyright Zitova B., Kautsky J., Peters G., Flusser J.
% UTIA, 1998

if prod(size(f1)) > 1, 
   X=conv2(X,f1,'same'); 
end

[HGF,C]=hgicf2im(X,k);
maxHGF=max(HGF(:));

[HM,ANG,POS1,POS2]=hmscarp2(X,C,k,kr,f2);

% complete C and HGF (zero border, same size as X)
[m,n]=size(X);
y=k+1:n-k; x=k+1:m-k;
tt=zeros(m,n);  Cex=tt;
Cex(x,y)=C;
tt(x,y)=HGF;  HGF=tt;