enhancement of image sharpness with bilateral and adaptive bilateral filter matlab codes

This preserves sharp edges by systematically looping through each pixel and adjusting weights to the adjacent pixels accordingly.
% bif = bilateral filter
% im = input image
% sigd = domain parameter for spatial kernel
% sigr = range parmeter for intensity kernel
% n = noise intensity
% out = output image

% Code Developed BY : Suraj Kamya
% kamyasuraj[at]yahoo.com

% Other files used in this function
% rpadd = another function is used
% PSN = Peak Signal to noise ratio
% IEF = Image Enhancement Factor

% For ex.
% im=imread('bgray.jpg');
% out=bif(im,3,0.2,0.1);