guided image filtering

A function for guided image filtering

function filteredImage = guidedfilter(Im, GuideIm, windowSize, dist_std, range_std)
%%%
%Im = input image(grayscale)
%GuidedIm = guided image(grayscale)
%windowSize = size of the local windowSize
%distance_std = standard deviation for distance for central pixel
%range_std = stadnard deviation for intensity range
%filteredImage = output image
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%