choseimppointswithoutzeros.m

图像对齐（inage registration）工具箱

function [IMP_POINTS] = choseImpPointsWithoutZeros(IMAGE, FROMTHESEVALUES, n, halfSurSize)

% CHOSEIMPPPOINTSWITHOUT ZEROS - choses a given number of the best significant points
%				[IMP_POINTS] = choseImpPointsWithoutZeros(IMAGE, FROMTHESEVALUES, n, halfSurSize)
%
% IMP_POINTS: the array of the resulting significant points
% IMAGE: the image to be processed
% FROMTHESEVALUES: the array from which the significant points are calculated
% n: number of significant points
% halfSurSize: half of the size of the surroundings of a maximum where no other maximum should be found
%
% Copyright Zitova B., Kautsky J., Peters G., Flusser J.
% UTIA, 1998

FROMTHESEVALUES = abs(FROMTHESEVALUES);
% --- choose a given number of maximum values: ---

IMP_POINTS = zeros(size(FROMTHESEVALUES)); 
[i, j] = find(FROMTHESEVALUES==max(FROMTHESEVALUES(:)));
k=1;

while (k <= n)&(FROMTHESEVALUES(i(1),j(1))>0)
   dr = max(1,(i(1)-halfSurSize)):min(size(IMAGE,1),(i(1)+halfSurSize));
   dc = max(1,(j(1)-halfSurSize)):min(size(IMAGE,2),(j(1)+halfSurSize));
	patch = IMAGE(dr,dc);
	zeroLoc = patch == 0;
	%numOfZerosAround = sum(zeroLoc(:));
	numOfZerosAround = 0;
   Answer = ((i(1)>halfSurSize)&(i(1)<(size(IMAGE,1)-halfSurSize))&(j(1)>halfSurSize)&(j(1)<(size(IMAGE,2)-halfSurSize)));
   if (numOfZerosAround == 0)&(Answer)
      k = k + 1;
      IMP_POINTS(i(1), j(1))  = 1;         
		FROMTHESEVALUES(dr,dc)=0;        
   else
   	FROMTHESEVALUES(i(1), j(1)) = 0;
   end           
   [i, j] = find(FROMTHESEVALUES==max(FROMTHESEVALUES(:)));
end