saeshma_OAM_OSM_LC.zip

close all; clear all; [audio, Fs] = audioread('Immigrant Song.mp3'); x_OAM = audio; x_OSM = audio; player0 = audioplayer(x_OAM, Fs); % play(player0) % stop(player0) %% Filter b = [0.2]; a = [1 -0.8]; [h,t] = impz(b,a); h = [h h]; % concatenação do vetor - matriz nx2 - n é a quantidade de linhas nem precisa % transformar o filtro em matriz, basta convoluir com -> h no lugar de h(:,1) ou h(:,2) %% Linear Convolution lc1 = conv(x_OAM(:,1), h(:,1)); lc2 = conv(x_OAM(:,2), h(:,2)); lc = [lc1 lc2]; %% L = 10000; N1 = length(x_OAM); M = length(h); h = [h; zeros(L-1, 2)]; H1 = fft(h(:,1),L+M-1); H2 = fft(h(:,2),L+M-1); H = [H1 H2]; %% Overlap and Add x_OAM = [x_OAM; zeros(mod(-N1,L), 2)]; %OAM - Overlap-add Method N2 = length(x_OAM); S = N2/L; idx = 1:L; X_OAM = [zeros(M-1,2)]; for stage = 1:S % Selecting sequence to process xm = [x_OAM(idx,:); zeros(M-1, 2)]; X1 = fft(xm(:,:), L+M-1); Y = X1 .* H; Y = ifft(Y); % Samples Added in every stage Z1 = X_OAM((length(X_OAM)-M+2):length(X_OAM),1) + Y(1:M-1,1); % Channel 1 Z2 = X_OAM((length(X_OAM)-M+2):length(X_OAM),2) + Y(1:M-1,2); % Channel 2 Z = [Z1 Z2]; X_OAM = [X_OAM(1:(stage-1)*L,:); Z(:,:); Y(M:M+L-1, :)]; idx = stage*L+1:(stage+1)*L; end ii = 1 : N1+M-1; X_OAM = X_OAM(ii,:); similarity_OAM = corrcoef(X_OAM, lc) %% Overlap and Save x_OSM = [x_OSM; zeros(mod(-N1,L), 2); zeros(L, 2)]; N2 = length(x_OSM); S = N2/L; idx0 = 1:L; xm = x_OSM(idx0, :); % For first stage Special Case x1 = [zeros(M-1, 2); xm]; % zeros appeded at Start point X_OSM = []; for stage=1:S X1 = fft(x1(:,:), L+M-1); Y = X1 .* H; Y = ifft(Y); Y = Y(M:M+L-1, :); %Discarding Samples X_OSM = [X_OSM; Y]; idx1 = ((stage*L)-M+2):((stage+1)*L); % Selecting Sequence to process if idx1(L+M-1) <= N2 x1 = x_OSM(idx1, :); end end jj = 1:N1+M-1; X_OSM = X_OSM(jj,:); similarity_OSM = corrcoef(X_OSM,lc) %% Play Music player0 = audioplayer(X_OAM, Fs); %play(player0) %stop(player0) player1 = audioplayer(X_OSM, Fs); %play(player1) %stop(player1) %% Plots figure() subplot(3,1,1); plot(lc); title('Convolution Using conv() function') xlabel('n'); ylabel('y(n)'); subplot(3,1,2); plot(X_OAM); title('Convolution Using Overlap Add Method') xlabel('n'); ylabel('y(n)'); subplot(3,1,3); plot(X_OSM); title('Convolution Using Overlap Save Method') xlabel('n'); ylabel('y(n)');