求图像增强的 幂次变换 的程序(MATLAB)

close all;
clear all;
clc;

im = imread('shit.jpg');
figure,imshow(im),title('yuan tu');
im1 = rgb2gray(im);
figure,imshow(im1);
im2 = im2double(im1)
[M,N] = size(im1);
for i=1:M
for j=1:N
im2(i,j)=exp(im2(i,j))-1;/exp是以e的幂变换
end
end
figure,imshow(im2);