MATLAB 求灰度图像最大灰度，最小灰度，平均灰度

 1 cl;
 2 img=imread('15.bmp');
 3 %imshow(img);
 4 [m n]=size(img);
 5 max=0;
 6 min=256;
 7 avg=0;
 8 for i=1:1:m
 9     for j=1:1:n
10         if img(i,j)<min
11             min=img(i,j);
12         end
13         if img(i,j)>max
14             max=img(i,j);
15         end
16         avg=avg+double(img(i,j));
17     end
18 end
19 
20 %avg=mean(mean(img));
21 avg=uint8(avg/(m*n));
22 max
23 min
24 avg