lighten.m.txt

灰度图象的直方图均衡化；梯度；直方图规定化；灰度图象的直方图数据；灰度直接变换:增强对比度

%灰度直接变换:增强对比度
function ch4_2_1()
file='pout.tif';
fig = imread(file);
f0=fig;
fig = double(fig);
f1=lighten(fig);    %调用增强对比度
figure(1);subplot(1,2,1);imshow(f0);title('原图');
subplot(1,2,2);imshow(f1);title('增强对比度图');

%增强对比度
function g=lighten(f)
a = 10;b = 100;c =80;d = 200;gray = 255;%灰度图;d=140
a = 80;b =150;c =50;d = 200;gray = 255;%灰度图;d=140
[row col] = size(f);
for i = 1:row
    for j = 1:col
        if f(i,j) < a | f(i,j) > b  
            g(i,j) = f(i,j); 
        else
            g(i,j) = (d-c)/(b-a)*(f(i,j)-a)+c;
        end;
%      g(i,j)=f(i,j)*2;
    end;
end;
g = uint8(g);