% GAUSSIAN_MEX gaussian smoothing in C for speedup. It utilizes the code from Anthony
% Gabrielson to do the actual computations (see MEX/gaussian_smooth.c).
%
%   GAU = GAUSSIAN_MEX(IMG, SIGMA) applies a gaussian filtering with a SIGMA kernal.
%
% Gonczy & Naef labs, EPFL
% Simon Blanchoud
% 16.05.2014