function fd =  mmfractal( f, range, option )
%  MMFRACTAL Compute the fractal dimension of a binary image using Minkowski sausage model.
%
%  FD =  MMFRACTAL( F, RANGE, OPTION )
%
%  Input:
%    F - Binary image (logical uint8).
%    RANGE - Gray-scale (uint8 or uint16) or binary image (logical
%        uint8). Vector with linearly increasing radius of the disk
%        used in the dilation. Selects to portion to use the fitting
%        in determine the line slope.
%    OPTION - String. optionally show plot to visualize the slope. '
%        PLOT' or 'NOPLOT'. DEFAULT: 'PLOT'.
%
%  Output:
%    FD -  Fractal dimension.
%
%  Measures the natural logarithm decay of the area of the dilation
%    minus erosion divided by the diameter of the Euclidean disk used
%    in the dilation. The range sets the minimum and maximum diameter
%    where the fitting is made. The plot of the fitting is shown.
%
%  Examples
%  --------
%
%  f1=mmreadgray('gear.tif');
%  mmshow(f1);
%  fd1=mmfractal(f1,[5:15])
%  showfig(slope_fd1);
%  f2=mmopen(f1,mmsedisk(2));
%  mmshow(f2);
%  fd2=mmfractal(f2,[5:15])
%  showfig(slope_fd2);
%

% begin of the default argument automatic treatment


if ~exist('option','var') option = 'PLOT'; end
% end of the default argument automatic treatment 1

g=mmgradm(f);
d=mmdist(mmneg(g),mmsebox,'euclidean');
h=double(mmhistogram(d));
hacc=cumsum(h)';
xall=1:length(h);
yall=hacc(xall)./(2*xall);
x=log(range);
y=log(hacc(range)./(2*range));
[p s]=polyfit(x,y,1); % p(1) is the inclination
if strcmp(upper(option),'PLOT')
  plot(log(xall),log(yall),'.-',x,polyval(p,x),'r');figure(gcf);
end
fd=-(-1+p(1));


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