%%影象加入噪聲
m=imread('E:/hough4.jpg');
M=rgb2gray(m); %==濾波函式都是對二維灰度圖，Tif可直接濾波
subplot(3,3,1)
imshow(M);%顯示原始影象
title('original')
P1=imnoise(M,'gaussian',0.02); %加入高斯躁聲
subplot(3,3,2)
imshow(P1) %加入高斯躁聲後顯示影象
title('gaussian noise');
P2=imnoise(M,'salt & pepper',0.02); %=加入椒鹽躁聲
subplot(3,3,3)
imshow(P2) %%加入椒鹽躁聲後顯示影象
title('salt & pepper noise');
g=medfilt2(P1); %對高斯躁聲中值濾波
subplot(3,3,5)
imshow(g)
title('medfilter gaussian')
h=medfilt2(P2); %對椒鹽躁聲中值濾波
subplot(3,3,6)
imshow(h)
title('medfilter salt & pepper noise')
l=[1 1 1 %對高斯躁聲算術均值濾波
1 1 1
1 1 1];
l=l/9;
k=conv2(P1,l);
subplot(3,3,8)
imshow(k,[])
title('arithmeticfilter gaussian')
%對椒鹽躁聲算術均值濾波
d=conv2(P2,l);
subplot(3,3,9)
imshow(d,[])
title('arithmeticfilter salt & pepper noise')