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clc;
clear all; I=imread('eight.tif'); % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % %用中值滤波,多维滤波,使用中心为-4,-8的拉普 % %拉斯滤波器,高斯低通滤波,拉普拉斯滤波器进行滤波处理 % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% figure;%figure1 subplot(2,2,1); imshow(I); title('原始图像'); J=imnoise(I,'salt & pepper',0.04);%加椒盐噪声 title('加椒盐噪声'); subplot(2,2,2); imshow(J); K=medfilt2(J,[4,4])%进行中值滤波; subplot(2,2,3); imshow(K); title('进行中值滤波'); h=ones(3,3)/9;%多维滤波 w=h; g=imfilter(I,w,'conv','replicate') subplot(2,2,4); imshow(g); title('多维滤波'); %使用中心为-4,-8的拉普拉斯滤波器, w4=[1 1 1; 1 -4 1; 1 1 1]; w8=[1 1 1; 1 -8 1; 1 1 1]; f=im2double(I); g4=f-imfilter(f,w4,'replicate'); g8=f-imfilter(f,w8,'replicate'); imshow(f); figure;%figure2 subplot(1,2,1); imshow(g4); title('中心为-4的拉普拉斯滤波'); subplot(1,2,2); imshow(g8); title('中心为-8的拉普拉斯滤波'); h3=fspecial('gaussian',[3,3],0.5);%高斯低通滤波 figure;%figure3 B4=filter2(h3,I); subplot(1,2,1); imshow(B4,[ ]); title('高斯低通滤波'); h4=fspecial('laplacian',0);%使用拉普拉斯滤波器 B5=filter2(h4,I); subplot(1,2,2); imshow(B5,[ ]); title('拉普拉斯滤波器'); % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % %从空域的角度进行亮度变换 % %把灰度等级是10-100的变化到10-255 % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% figure;%figure4 subplot(2,2,1); imshow(I); title('原始图像'); J2=imadjust(I,[],[],0.5);% 增强低灰度级 subplot(2,2,2); imshow(J2); title('增强低灰度级'); J3=imadjust(I,[ ],[ ],2);%增强高灰度级 subplot(2,2,3); imshow(J3); title('增强高灰度级'); a1=100/255;%把灰度等级是10-100的变化到10-255 a2=255/255; a3=10/255; J2=imadjust(I,[a3,a1],[a3,a2],[]); subplot(2,2,4); imshow(J2); title('把灰度等级是10-100的变化到10-255'); % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % %从频域的角度进行亮度变换 % %fft2 % %由于能量主要集中在低频部分 % %所以对低频进行处理可以得到理想的效果 % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% I=imread('eight.tif'); up=0.5;%设置处理频率上限 down=0.09%%设置处理频率下限 figure;%figure5 subplot(421); imshow(I); title('原始图像'); f=double(I); subplot(4,2,3); imshow(log(abs(f)),[]); title('unit8转化为double'); g=fft2(f); g=fftshift(g); subplot(4,2,5); imshow(log(abs(g)),[]); title('FFT2变化后的图像'); [M,N]=size(g);% 转换数据矩阵 y1=max(max(abs(g)));%求出最大频率 y2=min(min(abs(g)));%%求出最小频率 y3=(y1-y2)*up+y2;%设置滤波上限 y4=(y1-y2)*down+y2;%%设置滤波下限 for i=1:M for j=1:N if (abs(g(i,j))<y4) g(i,j)=g(i,j)^1.1;%对低频部分进行灰度增强 end end end result=ifftshift(g); J2=ifft2(result); J3=uint8(abs(J2)); subplot(427); imshow(J3,[ ]); title('频域处理后的图像'); subplot(422) imhist(I,64); subplot(424) imhist(f,64); subplot(426) imhist(g,64); subplot(428) imhist(J3,64);*****************************
clc;
clear; I=imread('a.jpg'); %读取图像 K1=medfilt2(I,[10 10]); %中值滤波 h1=ones(5,5)/25; K2=imfilter(K1,h1); %均值滤波 figure, imshow(K2), title('滤波后的图像')转载地址:http://bpjef.baihongyu.com/