菜鸟求《基于线性变换的图像增强处理》的matlab程序，我是菜鸟，所以希望高手能给出句子注释，急！

Answer 1

读入图像为A
A = im2double(A);
subplot(2,2,1),imshow(A)
subplot(2,2,2),imhist(A)
[m,n] = size(A);
B=A;
for i=1:m
for j=1:n
if( A(i,j)>130/255 & A(i,j)<=150/255 )
B(i,j)=B(i,j)/3-40/255;
continue;
end
if( A(i,j)>150/255 & A(i,j)<=240/255 )
B(i,j)=8*B(i,j)/3-390/255;
continue;
end
if( A(i,j)>240/255 )
B(i,j)=B(i,j)/3+170/255;
continue;
end
end
end
subplot(2,2,3),imshow(B)
subplot(2,2,4),imhist(B)

Answer 2

灰度变换增强程序：
% GRAY TRANSFORM
clc;
I=imread('pout.tif');
imshow(I);
J=imadjust(I,[0.3 0.7],[0 1],1); %transforms the walues in the %intensity image I to values in J by linealy mapping values
% between 0.3 and 0.7 to values between 0 and 1.
figure;
imshow(J);