function varargout = spm_resels_vol(varargin)
% computes the number of resels in a volume - a compiled routine
% FORMAT R = spm_resels_vol(V,W)
% V      -  is a memory mapped image volume.
%           Finite and non-zero values are considered to be part of
%           the search volume.
% W      -  smoothness of the component fields {FWHM in voxels}.
% R      - Resel counts, where:
%          R(1) - Euler Characteristic of the volume (number of connected
%                 components - number of holes).
%          R(2) - Resel Diameter (average over all rotations of the
%                 distance between two parallel planes tangent to the
%                 volume in resel space).
%          R(3) - Resel Surface Area (half the surface area of the
%                 volume in resel space).
%          R(4) - Resel Volume (the volume in resel space).
%_______________________________________________________________________
%
% Reference : Worsley KJ et al 1996, Hum Brain Mapp. 4:58-73
%_______________________________________________________________________
% Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging

% John Ashburner
% $Id: spm_resels_vol.m 1143 2008-02-07 19:33:33Z spm $


%-This is merely the help file for the compiled routine
error('spm_resels_vol.c not compiled - see Makefile')