37 lines
1.1 KiB
Matlab
37 lines
1.1 KiB
Matlab
function output = DarellAmplitudeEnvelope(input, Fs, attack,decay,sustain,release) %percentages for attack, decay, sustain, release
|
|
len = length(input);
|
|
T = (len-1)/Fs;
|
|
attacktime = attack * T * Fs;
|
|
decaytime = attacktime + decay * T * Fs;
|
|
sustaintime = (T - (release * T))* Fs;
|
|
|
|
x = 0:1/Fs:T;
|
|
y = 0 .* x; %create zero array of y of len x
|
|
output = y;%create zero array of output of len x
|
|
tcounter = 1;
|
|
%attack phase
|
|
while tcounter <= attacktime
|
|
y(tcounter) = (1/attacktime) * tcounter;
|
|
tcounter = tcounter+1;
|
|
end
|
|
istart = tcounter;
|
|
while tcounter<= decaytime
|
|
y(tcounter) = 1 - (((1-sustain)/(decay * T * Fs)) * (tcounter - istart));
|
|
tcounter = tcounter+1;
|
|
end
|
|
|
|
while tcounter<= sustaintime
|
|
y(tcounter) = sustain;
|
|
tcounter = tcounter+1;
|
|
end
|
|
istart = tcounter;
|
|
while tcounter < (T * Fs)
|
|
y(tcounter) = sustain - ((sustain/(release * T * Fs)) * (tcounter - istart));
|
|
tcounter = tcounter+1;
|
|
end
|
|
|
|
for counter = 1:1:len
|
|
output(counter) = y(counter) * input(counter);
|
|
end
|
|
|
|
end |