/normxcorr/trunk

function xyinput = dic_cpcorr(CORRSIZE, PRECISION, OPTIMIZE, hwid, base, xyinput_in, input)

%   Copyright 1993-2004 The MathWorks, Inc.

%   $Revision: 1.16.4.4 $  $Date: 2004/10/20 17:54:13 $

if any(xyinput_in(:)<0.5) || any(xyinput_in(:,1)>size(input,2)+0.5) || ...

   any(xyinput_in(:,2)>size(input,1)+0.5)

    msg = sprintf('In function %s, Control Points must be in pixel coordinates.',mfilename);

    eid = sprintf('Images:%s:cpPointsMustBeInPixCoord',mfilename);

    error(eid,msg);

end

% get all rectangle coordinates

rects_input = dic_calc_rects(xyinput_in, CORRSIZE, input);

ncp = size(xyinput_in,1);

xyinput = xyinput_in; % initialize adjusted control points matrix

for icp = 1:ncp

    if base(icp).skip

	% baned by base image (Nan, Inf, Near to edge, ...)

	continue

    end

    if isequal(rects_input(icp,3:4),[0 0])

        % near edge, unable to adjust

        continue

    end

    sub_input = imcrop(input,rects_input(icp,:));

    inputsize = size(sub_input);

    % make sure finite

    if any(~isfinite(sub_input(:))) 

        % NaN or Inf, unable to adjust

        continue

    end

    sum_T = sum(sub_input(:));

    % DS: double is required by 2007+ versions of Matlab for not known reasons

    denom_T = std(double(sub_input(:)));

    % check that template rectangle sub_input has nonzero std

    if denom_T==0

        % zero standard deviation of template image, unable to adjust

        continue

    end

    norm_cross_corr = dic_normxcorr2(OPTIMIZE, hwid, icp, sub_input, base(icp), sum_T, denom_T);

    % get subpixel resolution from cross correlation

    subpixel = true;

    [xpeak, ypeak, amplitude] = findpeak(norm_cross_corr,subpixel);

    % eliminate any poor correlations

    THRESHOLD = 0.5;

    if (amplitude < THRESHOLD) 

        % low correlation, unable to adjust

        continue

    end

    % offset found by cross correlation

    corr_offset = [ (xpeak-inputsize(2)-CORRSIZE) (ypeak-inputsize(1)-CORRSIZE) ];

    % eliminate any big changes in control points

    ind = find(abs(corr_offset) > (CORRSIZE-1));

    if ~isempty(ind)

        % peak of norxcorr2 not well constrained, unable to adjust

        continue

    end

    input_fractional_offset = xyinput(icp,:) - round(xyinput(icp,:)*PRECISION)/PRECISION;

    % adjust control point

    xyinput(icp,:) = xyinput(icp,:) - input_fractional_offset - corr_offset + base(icp).base_fractional_offset;

end