% 灰度圖像取反  s043
I43=imread('1.jpg');
I430=rgb2gray(I43);
I431=im2double(I430);
[m,n]=size(I430);
for i=1:m
    for j=1:n
        I432(i,j)=1-I431(i,j);
    end
end
I433=im2uint8(I432);
imshow(I433)