function ofNm = zeronan(ifNm)
% FORMAT ofNm = zeronan(ifNm)
% ifNm  - Input filename(s)
%
% Output:
% ofNm  - Cell array of output filenames.
%
%
% Images have NaN's replaced with zeros, and new images, prefixed with a
% 'z', are created.
%
%________________________________________________________________________
% @(#)zeronan.m	1.1 T. Nichols 02/08/21

if ~iscell(ifNm)
  ifNm = cellstr(ifNm)';
else
  ifNm = ifNm(:)';
end

OtfNm = {};

for fNm = ifNm

  fNm = fNm{:};

  OfNm = ['z' fNm];
  [pth,nm,xt] = fileparts(fNm);
  OfNm = fullfile(pth,['z' nm xt]);

  % Code snippet from John Ashburner...
  VI       = spm_vol(fNm);
  VO       = VI;
  VO.fname = OfNm;
  VO       = spm_create_image(VO);
  for i=1:VI.dim(3),
    img      = spm_slice_vol(VI,spm_matrix([0 0 i]),VI.dim(1:2),0);
    tmp      = find(isnan(img));
    img(tmp) = 0;
    VO       = spm_write_plane(VO,img,i);
  end;
  
  OtfNm = {OtfNm{:} OfNm};
  

end

if nargout>0
  ofNm = OtfNm;
end