/normxcorr/trunk

function rect = dic_calc_rects(xy,halfwidth,img)

% Calculate rectangles so imcrop will return image with xy coordinate inside center pixel

default_width = 2*halfwidth;

default_height = default_width;

% xy specifies center of rectangle, need upper left

upperleft = round(xy) - halfwidth;

% need to modify for pixels near edge of images

upper = upperleft(:,2);

left = upperleft(:,1);

lower = upper + default_height;

right = left + default_width;

width = default_width * ones(size(upper));

height = default_height * ones(size(upper));

% check edges for coordinates outside image

[upper,height] = adjust_lo_edge(upper,1,height);

[dum,height] = adjust_hi_edge(lower,size(img,1),height);

[left,width] = adjust_lo_edge(left,1,width);

[dum,width] = adjust_hi_edge(right,size(img,2),width);

% set width and height to zero when less than default size

iw = find(width<default_width);

ih = find(height<default_height);

idx = unique([iw; ih]);

width(idx) = 0;

height(idx) = 0;

rect = [left upper width height];

%-------------------------------

%

function [coordinates, breadth] = adjust_lo_edge(coordinates,edge,breadth)

indx = find( coordinates<edge );

if ~isempty(indx)

    breadth(indx) = breadth(indx) - abs(coordinates(indx)-edge);

    coordinates(indx) = edge;

end

%-------------------------------

%

function [coordinates, breadth] = adjust_hi_edge(coordinates,edge,breadth)

indx = find( coordinates>edge );

if ~isempty(indx)

    breadth(indx) = breadth(indx) - abs(coordinates(indx)-edge);

    coordinates(indx) = edge;

end