自适应中值滤波算法

clc;
clear;
f=imread('D:\newfiles\示例.jpg');
image_gray=rgb2gray(f);%得到灰度图像
ff =image_gray;
ff(:) = 0;
alreadyProcessed = false(size(image_gray));%生成逻辑非的矩阵
% 迭代.
Smax=7;
for k = 3:2:Smax
zmin = ordfilt2(image_gray, 1, ones(k, k), 'symmetric');
zmax = ordfilt2(image_gray, k * k, ones(k, k), 'symmetric');
zmed = medfilt2(image_gray, [k k], 'symmetric');

processUsingLevelB = (zmed > zmin) & (zmax > zmed) & ...
~alreadyProcessed;
zB = (image_gray > zmin) & (zmax > image_gray);
outputZxy = processUsingLevelB & zB;
outputZmed = processUsingLevelB & ~zB;
ff(outputZxy) = image_gray(outputZxy);
ff(outputZmed) = zmed(outputZmed);

alreadyProcessed = alreadyProcessed | processUsingLevelB;
if all(alreadyProcessed(:))
break;
end
end
ff(~alreadyProcessed) = zmed(~alreadyProcessed);
f1=imnoise(image_gray,'salt & pepper',0.3);%添加椒盐噪声后的图像
f2=medfilt2(f1,[3,3]);%中值滤波后的图像
subplot(2,2,1);
imshow(image_gray);
title('原图');
subplot(2,2,2);
imshow(f1);
title('椒盐噪声污染后的图像');
subplot(2,2,3);
imshow(f2);
title('中值滤波');
subplot(2,2,4);
imshow(ff);
title('自适应中值滤波');