均值滤波与中值滤波在一维信号中的应用.rar

clear all; t=0:0.01:1; f2=5; %生成一个正弦信号y； y1=1*sin(2*pi*f2*t); %y1=square(2*pi*f2*t); %向y中加入噪声信号生成x; x1=y1+0.1*randn(1,101); figure(1) subplot(2,1,1); plot(t,y1,'r');title('生成一个正弦信号y');grid;legend y; subplot(2,1,2); plot(t, x1,'r');title('向y中加入噪声信号生成x');grid; legend x; X=1:length(x1) for X=1:length(x1) z1=smooth(x1,3);%M=3时的均值滤波 end for X=1:length(x1) z2=smooth(x1,5);%M=5时的均值滤波 end for X=1:length(x1) z3=smooth(x1,7);%M=3时的均值滤波 end figure(2) subplot(3,1,1); plot(t,z1,'r');title('M=3时的均值滤波处理后的信号');grid; legend y; subplot(3,1,2); plot(t,z1,'r');title('M=5时的均值滤波处理后的信号');grid; legend y; subplot(3,1,3); plot(t,z1,'r');title('M=7时的均值滤波处理后的信号');grid; legend y; for X=1:length(x1) L1= median(x1,3); end for X=1:length(x1) L2= median(x1,5); end for X=1:length(x1) L3= median(x1,7); end figure(3) subplot(3,1,1); plot(t,L1,'r');title('M=3时的中值值滤波处理后的信号');grid; legend y; subplot(3,1,2); plot(t,L2,'r');title('M=5时的中值值滤波处理后的信号');grid; legend y; subplot(3,1,3); plot(t,L2,'r');title('M=7时的中值值滤波处理后的信号');grid; legend y; %Y1=x1; %n = length(Y1); %K=(n-1)/2; %for t=0:n %for i = 1:n-1 % for j = i+1:n % if( Y1(i)>Y1(j)) % tmp = Y1(j); % Y1(j) = Y1(i); % Y1(i) = tmp; %end %end %end %x1(K)=Y1(i); %end %subplot(3,1,3); %plot(t,x1,'g');title('用中值滤波处理后提取出原始信号');grid; legend y;