% Efekty dźwiękowe
clc; clear all; close all;


%--------------------------------------------------------------------------
% echo:

[in, Fs] = wavread('sound.wav');
disp('Dlugosc trwania pliku:');
soundTimeLength = length(in)/Fs

delay = input('Wprowadz opoznienie w ms: ');
D = floor(Fs * delay / 1000)
%a = input('Wprowadz współczynnik tłumienia: ');
a = 0.1;

out = zeros(length(in)+D,1);
out(1:D) = in(1:D);

for i=(1+D):length(in)
    out(i) = in(i) + a * in(i-D);
end

for i=length(in)+1:length(out)
   out(i) =  a * in(i-D);
end

% sound(out);
% wavwrite(out,Fs,[fileName '_echo.wav']);


%--------------------------------------------------------------------------
% pogłos:

D2 = 50000;
in2 = in;
for j=1 : 10
    if j ~= 1
        in2 = out2;
    end
    
    out2 = zeros(length(in)+D2,1);
    out2(1:D2) = in2(1:D2);

    for i=(1+D2):length(in2)
        out2(i) = in2(i) + a * in2(i-D2);
    end

    for i=length(in2)+1:length(out2)
       out2(i) =  a * in2(i-D2);
    end
end