function lowpass, array
	result=array
	x = (size(array))(1) - 2
	y = (size(array))(2) - 2
	

	for i=1, x do begin
		for j=1,y do begin
			result(i,j) = mean(array(i-1:i+1,j-1:j+1))
		endfor
	endfor
	
	return, result
	
end