added matlab

This commit is contained in:
2025-08-21 07:27:52 +02:00
parent fd522e1b99
commit 64c6745c76
50 changed files with 2516 additions and 0 deletions
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function eval_adsr(Ta, Td, Vs, Tr, ks)
% eval_adsr(0.1, 0.2, 0.2, 0.2)
fs = 1000;
a_a = -log(1-ks)/(Ta*fs);
a_d = 5/(Td*fs);
a_r = 5/(Tr*fs);
state = 0;
s = 0;
tol = 1E-4;
n = 1;
p = 0;
k = 1/ks;
while (1),
if state == 0 % Attack
s = a_a + (1-a_a)*s;
y(n) = k*s;
if s >= (ks-tol)
state = 1;
s = 1-ks;
end;
end;
if state == 1 % Decay
s = (1-a_d)*s;
y(n) = s/(1-ks);
if s <= (Vs+tol)
state = 2;
p = 0;
end;
end;
if state == 2 % sustain
y(n) = Vs;
if p >= 1*fs
state = 3;
s = Vs;
end;
p = p + 1;
end;
if state == 3 % Release
s = (1-a_r)*s;
y(n) = s;
if s <= (tol)
break;
end;
end;
n = n + 1;
end;
plot((0:n-1)/fs, y); grid;
set(gca,'xtick',[0:0.1:(n-1)/fs])
Vendored Executable
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function eval_adsr(Ta, Td, Vs, Tr, ks)
% eval_adsr(0.1, 0.2, 0.2, 0.2)
fs = 1000;
a_a = -log(1-ks)/(Ta*fs);
a_d = 5/(Td*fs);
a_r = 5/(Tr*fs);
state = 0;
s = 0;
tol = 1E-4;
n = 1;
p = 0;
k = 1/ks;
while (1),
if state == 0 % Attack
s = a_a + (1-a_a)*s;
y(n) = s/ks;
if s >= (ks-tol)
state = 1;
end;
end;
if state == 1 % Decay
s = (1-a_d)*s;
y(n) = s/(ks);
if s <= (Vs*ks+tol)
state = 2;
p = 0;
end;
end;
if state == 2 % sustain
y(n) = Vs;
if p >= 1*fs
state = 3;
s = Vs;
end;
p = p + 1;
end;
if state == 3 % Release
s = (1-a_r)*s;
y(n) = s;
if s <= (tol)
break;
end;
end;
n = n + 1;
end;
plot((0:n-1)/fs, y); grid;
set(gca,'xtick',[0:0.1:(n-1)/fs])
Vendored Executable
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function eval_adsr(Ta, Td, Vs, Tr)
% eval_adsr(0.1, 0.2, 0.2, 0.2)
fs = 10000;
aa = 1/(Ta*fs)
ba = (1-aa)
a_d = 5/(Td*fs)
a_r = 5/(Tr*fs)
state = 0;
s = 0;
tol = 1E-4;
ke = 1-exp(-1)
n = 0;
p = 0;
k = 1/ke;
kk = 0;
s
while (1),
if state == 0
s = aa + ba*s;
if s >= (ke-tol)
state = 1;
k = (1-Vs)/ke;
kk = Vs;
end;
end;
if state == 1
s = (1-a_d)*s;
if s <= (tol)
state = 2;
s = 1;
k = Vs;
kk = 0;
p = 0;
end;
end;
if state == 2
if p >= 0.1*fs
state = 3;
end;
p = p + 1;
end;
if state == 3
s = (1-a_r)*s;
if s <= (tol)
break;
end;
end;
n = n + 1;
y(n) = k*s + kk;
end;
plot((0:n-1)/fs, 0.8-y); grid;
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function eval_adsr(Ta, Td, Vs, Tr)
% eval_adsr(0.1, 0.2, 0.2, 0.2)
fs = 1000;
a_a = 1/(Ta*fs);
a_d = -1/(Td*fs/log(Vs))
a_d = 5/(Td*fs)
a_r = 5/(Tr*fs)
state = 0;
s = 0;
tol = 1E-4;
target = 1;
n = 0;
p = 0;
k = 1/0.63;
while (1),
if state == 0 % Attack
s = a_a + (1-a_a)*s;
if s >= (0.63-tol)
state = 1
target = Vs;
end;
end;
if state == 1 % Decay
s = (1-a_d)*s;
if s <= (0.63*Vs+tol)
state = 2
target = 0;
p = 0;
end;
end;
if state == 2 % sustain
s = Vs/k;
if p >= 1*fs
state = 3
end;
p = p + 1;
end;
if state == 3 % Release
s = (1-a_r)*s;
if s <= (target+tol)
break;
end;
end;
n = n + 1;
y(n) = k*s;
end;
plot((0:n-1)/fs, y); grid;
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function eval_vcf_lut()
N = 1000;
fs = 48000;
fmin = 18;
fmax = 18000;
sweepbase = 10;
filterParam = struct('sweepbase', 10, 'omega_min', 2*fmin/fs, 'omega_max', 2*fmax/fs, 'num_octaves', log(fmax/fmin)/log(sweepbase));
filterParam
cv = (0:N-1)/N;
plot (c
function cv = omega2cv(filterParam, omega)
cv = log(omega/filterParam.omega_min)/(filterParam.num_octaves * log(filterParam.sweepbase));
cv = min(1, max(0, cv));
function omega = cv2omega(filterParam, cv)
omega = filterParam.omega_min*filterParam.sweepbase ^ (filterParam.num_octaves*min(1, max(0, cv)));
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function eval_vcf_lut()
N = 1000;
fs = 48000;
fmin = 18;
fmax = 18000;
sweepbase = 10;
filterParam = struct('sweepbase', 10, 'omega_min', fmin/fs, 'omega_max', fmax/fs, 'num_octaves', log(fmax/fmin)/log(sweepbase));
filterParam
cv = (0:N-1)/N;
subplot(2, 1, 1)
plot (cv, fs*cv2omega(filterParam, cv)); grid; legend('F'); xlabel('cv');
subplot(2, 1, 2)
plot (cv, cos(2*pi*cv2omega(filterParam, cv)), cv, sin(2*pi*cv2omega(filterParam, cv))); grid; legend('kc', 'ks'); xlabel('cv');
function cv = omega2cv(filterParam, omega)
cv = log(omega/filterParam.omega_min)/(filterParam.num_octaves * log(filterParam.sweepbase));
cv = min(1, max(0, cv));
function omega = cv2omega(filterParam, cv)
omega = filterParam.omega_min*filterParam.sweepbase .^ (filterParam.num_octaves*min(1, max(0, cv)));
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function eval_lfo()
L = 10000;
fs = 44100;
fstart = 40;
fend = 400;
df = (fend-fstart)/L;
ip = 0 % phase of the first output sample in radians
w = freq*pi / samplerate
b1 = 2.0 * cos(w)
% Init
y1=sin(ip-w)
y2=sin(ip-2*w)
% Loop
for n=1:L,
y0 = b1*y1 - y2
y2 = y1
y1 = y0
close all
figure;
plot(1:L, vsaw, 1:L, vblit); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblit, fs, 'blit.wav');
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function eval_lfo()
L = 10000;
fs = 44100;
fstart = 44;
fend = 400;
df = (fend-fstart)/L;
ip = 0 % phase of the first output sample in radians
% Init
% Loop
f = fstart;
fchg = 1;
y1=sin(ip-f*pi / fs);
y2=sin(ip-2*f*pi / fs);
for n=1:L,
if fchg == 1,
b1 = 2.0 * cos(f*pi / fs);
fchg = 1000;
end;
y0 = b1*y1 - y2;
y2 = y1;
y1 = y0;
fchg = fchg - 1;
lfo(n) = y0;
f = f + df;
close all
end;
figure;
plot(1:L, lfo); grid;
wavwrite(0.5*lfo, fs, 'lfo.wav');
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function eval_lfo2()
L = 80000;
fs = 48000;
fstart = 10;
fend = 1000;
df = (fend-fstart)/L;
ip = 0.0 % phase of the first output sample in radians
% Init
% Loop
f = fstart;
fchg = 0;
ylast = 0;
a = 0.5;
b = 2.0 * sin(f*pi / fs);
y0 = a*cos(2*pi*ip);
y1 = a*sin(2*pi*ip);
for n=1:L,
y0 = y0 - b*y1;
y1 = y1 + b*y0;
fchg = (mod(n, 1000) == 0);
if fchg
b = 2.0 * sin(f*pi / fs);
end
ylast = y1;
lfo(n) = y0;
f = f + df;
close all
end;
figure;
plot(1:L, lfo); grid;
wavwrite(0.5*lfo, fs, 'lfo.wav');
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function eval_lfo2()
L = 80000;
fs = 48000;
fstart = 10;
fend = 5000;
df = (fend-fstart)/L;
ip = 0.0 % phase of the first output sample in radians
% Init
% Loop
f = fstart;
fchg = 0;
ylast = 0;
a = 0.5;
b = 2.0 * sin(f*pi / fs);
y0 = a*cos(2*pi*ip);
y1 = a*sin(2*pi*ip);
for n=1:L,
y0 = y0 - b*y1;
y1 = y1 + b*y0;
fchg = (mod(n, 1000) == 0);
if fchg
b = 2.0 * sin(f*pi / fs);
end
ylast = y1;
lfo(n) = y0;
f = f + df;
close all
end;
figure;
plot(1:L, lfo); grid;
wavwrite(0.5*lfo, fs, 'lfo.wav');
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function eval_smooth(Ta)
fs = 10000;
b = 1;
if (abs(Ta) > 0)
b = 1/(abs(Ta)*fs);
end;
a = 1 - b;
x = [ zeros(1, 1000) ones(1, 1000) zeros(1, 1000)];
y = 0;
for i=1:length(x)
if (Ta < 0)
y = b*x(i) + a*y;
yn(i) = y;
end;
plot(yn); grid;
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function eval_smooth(Ta)
fs = 10000;
b = 1;
if (abs(Ta) > 0)
b = 1/(abs(Ta)*fs);
end;
a = 1 - b;
x = [ zeros(1, 1000) ones(1, 1000) zeros(1, 1000)];
N = length(x);
y = 0;
y1 = 0;
for i=1:length(x)
y1 = b*x(i) + a*y1;
% if (Ta > 0)
y1n(i) = y1;
% else
y2n(i) = 2*x(i) - y1;
% end
end;
subplot(3, 1, 1)
plot(1:N, x, 'r'); grid;
xlabel('Original LFO Wellenform (Square)')
subplot(3, 1, 2)
plot(1:N, y1n, 'r'); grid;
xlabel('Positive smoothed')
subplot(3, 1, 3)
plot(1:N, y2n, 'r'); grid;
xlabel('Negative smoothed')
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function eval_limiter(name)
Tr = 1; % ms
Tf = 100; % ms
input_gain = 2;
output_gain = 0.5;
limit_thresh = 0.25;
[x, fs, nbits, opts] = wavread(name);
x = x.*input_gain;
N = fix(length(x)/);
a_r = 1000/(Tr*fs);
a_f = 1000/(Tf*fs);
y = 0;
for n=1:N
if (y < abs(x(n)))
y = y + a_r*(abs(x(n)) - y);
else
y = y + a_f*(abs(x(n)) - y);
end
env(n) = y;
end;
limiter_gain = limit_thresh./max(limit_thresh, env)';
x_limited = x(1:N).*limiter_gain.*output_gain;
wavwrite(x_limited,fs,'limiter_out.wav');
subplot(2, 1, 1)
plot(0:N-1, x(1:N), 0:N-1, env, 'r-'); grid;
subplot(2, 1, 2)
plot(0:N-1, x_limited, 0:N-1, limiter_gain, 'r-'); grid;
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function eval_limiter(name)
Tr = 1; % ms
Tf = 100; % ms
input_gain = 2;
output_gain = 0.5;
limit_thresh = 0.25;
[x, fs, nbits, opts] = wavread(name);
x = x.*input_gain;
N = fix(length(x));
a_r = 1000/(Tr*fs);
a_f = 1000/(Tf*fs);
y = 0;
for n=1:N
if (y < abs(x(n)))
y = y + a_r*(abs(x(n)) - y);
else
y = y + a_f*(abs(x(n)) - y);
end
env(n) = y;
end;
limiter_gain = limit_thresh./max(limit_thresh, env)';
x_limited = x(1:N).*limiter_gain.*output_gain;
wavwrite(x_limited,fs,'limiter_out.wav');
subplot(2, 1, 1)
plot(0:N-1, x(1:N), 0:N-1, env, 'r-'); grid;
subplot(2, 1, 2)
plot(0:N-1, x_limited, 0:N-1, limiter_gain, 'r-'); grid;
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function eval_midi_sync(pe, fe)
N = 5000;
t = (0:N-1)/N;
x1 = mod(20*t, 1) >=0.5;
x2 = mod((20+fe)*t+pe, 1) >=0.5;
dx1 = 50/N
dx2 = (50+fe)/N
qi1 = 0;
qi2 = 0;
xi1 = 0;
xi2 = 0;
xx1 = 0;
xx2 = 0;
lead = 0;
lag = 0;
ddx = 0;
for i=1:N,
%[qi1, qi2, xi1, xi2] = pd(x1(i), x2(i), qi1, qi2, xi1, xi2);
[qi1, qi2, xi1, xi2] = pd(xx1 >=0.5, xx2 >=0.5, qi1, qi2, xi1, xi2);
err = (qi1-qi2);
lead = 0.*err;
lag = lag + 0.000001*err;
ddx = (lead+lag);
xx1 = mod(xx1 + dx1, 1);
xx2 = mod(xx2 + dx2 + ddx, 1);
q1(i) = qi1;
q2(i) = qi2;
end;
dx2 = dx2 + ddx
dx1 = dx1
subplot(3, 1, 1)
plot(t, x1, t, x2); grid; axis([0 1 -0.2 1.2])
subplot(3, 1, 2)
plot(t, q1); grid; axis([0 1 -0.2 1.2])
subplot(3, 1, 3)
plot(t, q2); grid; axis([0 1 -0.2 1.2])
function [Q1, Q2, xo1, xo2] = pd(x1, x2, qi1, qi2, xi1, xi2)
xo1 = xi1;
xo2 = xi2;
qo1 = qi1;
qo2 = qi2;
for i=1:length(x1)
% Q1
% Detect edge
if (x1(i) - xo1) > 0.5
qo1 = 1;
end;
xo1 = x1(i);
% Q2
% Detect edge
if (x2(i) - xo2) > 0.5
qo2 = 1;
end;
xo2 = x2(i);
% Asynchronous reset
if (qo1 * qo2) > 0.5
qo1 = 0;
qo2 = 0;
end;
Q1(i) = qo1;
Q2(i) = qo2;
end;
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function eval_midi_sync(pe, fe)
N = 5000;
t = (0:N-1)/N;
dx1 = 40/N
dx2 = (40+fe)/N
qi1 = 0;
qi2 = 0;
xi1 = 0;
xi2 = 0;
xx1 = 0;
xx2 = pe;
lead = 0;
lag = 0;
ddx = 0;
for i=1:N,
[qi1, qi2, xi1, xi2] = pd(xx1 >=0.5, xx2 >=0.5, qi1, qi2, xi1, xi2);
err = (qi1-qi2);
lead = 0.002*err;
lag = lag + 0.000005*err;
ddx(i) = (lead+lag);
xx1 = mod(xx1 + dx1, 1);
xx2 = mod(xx2 + dx2 + ddx(i), 1);
q1(i) = qi1;
q2(i) = qi2;
x1(i) = xx1 >=0.5;
x2(i) = xx2 >=0.5;
end;
subplot(4, 1, 1)
plot(t, x1, t, x2); grid; axis([0 1 -0.2 1.2])
subplot(4, 1, 2)
plot(t, q1); grid; axis([0 1 -0.2 1.2])
subplot(4, 1, 3)
plot(t, q2); grid; axis([0 1 -0.2 1.2])
subplot(4, 1, 4)
plot(t, ddx); grid;
function [Q1, Q2, xo1, xo2] = pd(x1, x2, qi1, qi2, xi1, xi2)
xo1 = xi1;
xo2 = xi2;
qo1 = qi1;
qo2 = qi2;
for i=1:length(x1)
% Q1
% Detect edge
if (x1(i) - xo1) > 0.5
qo1 = 1;
end;
xo1 = x1(i);
% Q2
% Detect edge
if (x2(i) - xo2) > 0.5
qo2 = 1;
end;
xo2 = x2(i);
% Asynchronous reset
if (qo1 * qo2) > 0.5
qo1 = 0;
qo2 = 0;
end;
Q1(i) = qo1;
Q2(i) = qo2;
end;
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function eval_minblep()
nsin = 4096;
nharm_max = 1800;
L = 48000/2;
fs = 48000;
fstart = 440;
fend = 440;
f2start = 200;
f2end = 600;
df = (fend-fstart)/L
df2 = (f2end-f2start)/L
saw = 0;
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm
blitm(mm,:) = sin(xx*(mm-1)*pi)./sin(xx*pi).*Hw';
blitm(mm,(find(isnan(blitm(mm,:))))) = (mm-1);
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
w = [1; 2*ones(nsin/2-1,1); ones(1 - rem(nsin,2),1); zeros(nsin/2-1,1)]';
for mm=1:nharm
x_rc = real(ifft(log(abs(fft(blitm(mm, :))))));
y = real(ifft(exp(fft(w.*x_rc))));
minblepm(mm, :) = cumsum(y)/nsin;
end;
x = 0;
x2 = 0;
z = 0;
f = fstart;
f2 = f2start;
tri = 0;
NLG = 2;
h = lagrange(1, 0.35)
startup = 1;
blep = 1;
for n = 1:L,
if x >= 1 || startup,
x = 0;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
blep_offset = 0;
blep_gain = 1;
z = ~z;
end;
if x2 >= 1 || startup,
x2 =0;
dx2 = f2/fs;
% blep_offset = -(1-x);
% blep_gain = x;
% x = 0;
% z = ~z;
end;
startup = 0;
nn = (x+0.0)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep = h(NLG+1)*minblepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*minblepm(m, max(1, ni-j));
j = j + 1;
end;
saw = x - blep_gain*blep + blep_offset;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
tri = tri + 2*(sqr-0.5)*dx;
vsqr(n) = 0.5*(sqr-0.5);
vtri(n) = tri;
vsaw(n,1) = x;
vsaw(n,2) = saw+0.5;
vblep(n,1) = x;
vblep(n,2) = blep;
x = x + dx;
f = f + df;
x2 = x2 + dx2;
f2 = f2 + df2;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :), 1:nsin, minblepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_minblep()
nsin = 4096;
nharm_max = 1800;
L = 48000/2;
fs = 48000;
fstart = 440;
fend = 440;
df = (fend-fstart)/L
f2start = 200;
f2end = 600;
df2 = (f2end-f2start)/L
saw = 0;
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm
blitm(mm,:) = sin(xx*(mm-1)*pi)./sin(xx*pi).*Hw';
blitm(mm,(find(isnan(blitm(mm,:))))) = (mm-1);
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
w = [1; 2*ones(nsin/2-1,1); ones(1 - rem(nsin,2),1); zeros(nsin/2-1,1)]';
for mm=1:nharm
x_rc = real(ifft(log(abs(fft(blitm(mm, :))))));
y = real(ifft(exp(fft(w.*x_rc))));
minblepm(mm, :) = cumsum(y)/nsin;
end;
x = 0;
x2 = 0;
z = 0;
f = fstart;
f2 = f2start;
tri = 0;
NLG = 2;
h = lagrange(1, 0.35)
startup = 1;
blep = 1;
for n = 1:L,
if x >= 1 || startup,
x = 0;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
blep_offset = 0;
blep_gain = 1;
z = ~z;
end;
if x2 >= 1 || startup,
x2 =0;
dx2 = f2/fs;
% blep_offset = -(1-x);
% blep_gain = x;
% x = 0;
% z = ~z;
end;
startup = 0;
nn = (x+0.0)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep = h(NLG+1)*minblepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*minblepm(m, max(1, ni-j));
j = j + 1;
end;
saw = x - blep_gain*blep + blep_offset;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
vsqr(n) = 0.5*(sqr-0.5);
tri = tri + 2*(sqr-0.5)*dx;
vtri(n) = tri;
vsaw(n,1) = x;
vsaw(n,2) = saw+0.5;
vblep(n,1) = x;
vblep(n,2) = blep;
x = x + dx;
f = f + df;
x2 = x2 + dx2;
f2 = f2 + df2;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :), 1:nsin, minblepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_minblep_pre()
f = 440;
N = 4000;
t = (-N/2:N/2-1)/N;
x = sin(t*f*pi)./sin(t*pi); .* kaiser(N, 8)';
x(find(isnan(x))) = f;
%x = x / f;
% Real cepstrum
x_rc = real(ifft(log(abs(fft(x)))));
w = [1; 2*ones(N/2-1,1); ones(1 - rem(N,2),1); zeros(N/2-1,1)]';
y = real(ifft(exp(fft(w.*x_rc))));
xi = cumsum(x)/N;
yi = cumsum(y)/N;
close all;
subplot(2, 1, 1)
plot(t, x/f, t, xi, 'r'); grid;
subplot(2, 1, 2)
plot(0:N-1, y/f, 0:N-1, yi, 'r'); grid;
figure;
plot(t, xi); grid;
figure;
plot(t, yi); grid;
figure;
plot(w); grid;
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function eval_minblep_pre()
f = 440;
N = 4000;
t = (-N/2:N/2-1)/N;
x = sin(t*f*pi)./sin(t*pi);% .* kaiser(N, 8)';
x(find(isnan(x))) = f;
%x = x / f;
% Real cepstrum
x_rc = real(ifft(log(abs(fft(x)))));
w = [1; 2*ones(N/2-1,1); ones(1 - rem(N,2),1); zeros(N/2-1,1)]';
y = real(ifft(exp(fft(w.*x_rc))));
xi = cumsum(x)/N;
yi = cumsum(y)/N;
close all;
subplot(2, 1, 1)
plot(t, x/f, t, xi, 'r'); grid;
subplot(2, 1, 2)
plot(0:N-1, y/f, 0:N-1, yi, 'r'); grid;
figure;
plot(t, xi); grid;
figure;
plot(t, yi); grid;
figure;
plot(w); grid;
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function eval_blep()
nsin = 2048;
nharm_max = 1800;
L = 48000;
fs = 48000;
fstart = 110;
fend = 110;
df = (fend-fstart)/L
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm,
bb(mm, :) = sin((mm-1)*xx*pi);
end;
aa = sin(xx*pi);
for mm=1:nharm
for nn=1:length(xx)
if (aa(nn) == 0)
blitm(mm,nn) = (mm-1);
else
blitm(mm,nn) = bb(mm, nn)/aa(nn).*Hw(nn);
end
end
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
%blep2 = blepm(nharm_max/2+1, :)'
%aa2 = aa(:)'
%bb2 = bb(nharm_max/2+1, :)'
x = 0.5;
z = 0;
f = fstart;
tri = 0;
for n = 1:L,
if x >= 0.5,
x = x - 1;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
z = ~z;
end;
nn = (x+0.5)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(1, nf);
% blep = (blepm(m, min(ni+1, nsin)) - blepm(m, ni))*nf + blepm(m, ni);
[blep, Zi] = filter(h, 1, blepm(m
blep = h(1)*blepm(m, max(1, ni-1)) + h(2)*blepm(m, ni);
saw = x - blep;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
tri = tri + 2*(sqr-0.5)*dx;
vtri(n) = tri;
vsaw(n) = saw+0.5;
vsqr(n) = 0.5*(sqr-0.5);
vblep(n) = blep;
x = x + dx;
f = f + df;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_blep()
nsin = 4096;
nharm_max = 1800;
L = 48000/2;
fs = 48000;
fstart = 440;
fend = 440;
df = (fend-fstart)/L
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm
blitm(mm,:) = sin(xx*(mm-1)*pi)./sin(xx*pi).*Hw';
blitm(mm,(find(isnan(blitm(mm,:))))) = (mm-1);
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
x = 0.0;
z = 0;
f = fstart;
tri = 0;
NLG = 2;
h = lagrange(1, 0.35)
startup = 1;
for n = 1:L,
if x >= 0.5 || startup;
x = x - 1;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
z = ~z;
end;
startup = 0;
nn = (x+0.5)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep = h(NLG+1)*blepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*blepm(m, max(1, ni-j));
j = j + 1;
end;
saw = x - blep;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
vsqr(n) = 0.5*(sqr-0.5);
tri = tri + 2*(sqr-0.5)*dx;
vtri(n) = tri;
vsaw(n,1) = x;
vsaw(n,2) = saw+0.5;
vblep(n,1) = x;
vblep(n,2) = blep;
x = x + dx;
f = f + df;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_blep_hs()
nsin = 1024;
nharm_max = 1800;
L = 48000;
fs = 48000;
fstart = 44;
fend = 44;
df = (fend-fstart)/L
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm,
bb(mm, :) = sin((mm-1)*xx*pi);
end;
aa = sin(xx*pi);
for mm=1:nharm
for nn=1:length(xx)
if (aa(nn) == 0)
blitm(mm,nn) = (mm-1);
else
blitm(mm,nn) = bb(mm, nn)/aa(nn).*Hw(nn);
end
end
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
%blep2 = blepm(nharm_max/2+1, :)'
%aa2 = aa(:)'
%bb2 = bb(nharm_max/2+1, :)'
x = 0.5;
x2 = 0.5;
z = 0;
f = fstart;
tri = 0;
NLG = 2;
h = lagrange(1, 0.35)
for n = 1:L,
if x >= 0.5,
x = x - 1;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
z = ~z;
end;
nn = (x+0.5)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
% blep = (blepm(m, min(ni+1, nsin)) - blepm(m, ni))*nf + blepm(m, ni);
% blep = h(1)*blepm(m, max(1, ni-3)) + h(2)*blepm(m, max(1, ni-2)) + h(3)*blepm(m, max(1, ni-1)) + h(4)*blepm(m, max(1, ni));
blep = h(NLG+1)*blepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*blepm(m, max(1, ni-j));
j = j + 1;
end;
saw = x - blep;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
tri = tri + 2*(sqr-0.5)*dx;
vtri(n) = tri;
vsaw(n) = saw+0.5;
vsqr(n) = 0.5*(sqr-0.5);
vblep(n) = blep;
x = x + dx;
f = f + df;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_blep_hs()
nsin = 1024;
nharm_max = 256;
L = 4800;
fs = 48000;
fstart = 44;
fend = 44;
df = (fend-fstart)/L
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm,
bb(mm, :) = sin((mm-1)*xx*pi);
end;
aa = sin(xx*pi);
for mm=1:nharm
for nn=1:length(xx)
if (aa(nn) == 0)
blitm(mm,nn) = (mm-1);
else
blitm(mm,nn) = bb(mm, nn)/aa(nn).*Hw(nn);
end
end
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
%blep2 = blepm(nharm_max/2+1, :)'
%aa2 = aa(:)'
%bb2 = bb(nharm_max/2+1, :)'
x = 0.0;
x2 = -0.5;
z = 0;
f = fstart;
f2 = 0.6*f;
dx2 = f2/fs;
tri = 0;
NLG = 2;
h = lagrange(1, 0.35)
sync = 0;
restart = 0;
startup = 1;
minblep_active = 0;
minblep_count = 0;
minblep_length = 200;
minblep = 1-(0:minblep_length-1)/minblep_length;
for n = 1:L,
sync = 0;
if startup,
x = 0.0;
startup = 0;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
z = 0;
end;
if (x >= 0.5),
x = x - 1;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
z = ~z;
end;
if (x2 >= 0.5),
x2 = x2 - 1;
sync = 1;
startup = 1;
minblep_count = minblep_length;
end;
nn = (x+0.5)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep = h(NLG+1)*blepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*blepm(m, max(1, ni-j));
j = j + 1;
end;
if (minblep_count > 0)
saw = saw_last - minblep(minblep_count)/(1-2*saw_last+minblep_length*dx);
minblep_count = minblep_count - 1;
minblep_active = 1;
else
minblep_active = 0;
saw = x - blep;
saw_last = saw;
end
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
tri = tri + 2*(sqr-0.5)*dx;
vtri(n) = tri;
vsaw(n) = 2*(saw+0.5);
vsqr(n) = 0.5*(sqr-0.5);
vblep(n) = blep;
vx(n) = x;
vsync(n) = sync;
vminblep_active(n) = minblep_active;
x2 = x2 + dx2;
x = x + dx;
f = f + df;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :)); grid;
figure;
subplot(3, 1, 1)
plot(1:L, vx, 1:L, vsync, 'r'); grid;
subplot(3, 1, 2)
plot(1:L, vblep); grid;
subplot(3, 1, 3)
plot(1:L, vsaw, 1:L, vminblep_active); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_blit()
sinc_use_lut = 1
L = 40000;
fs = 48000;
fstart = 110;
fend = 1100;
df = (fend-fstart)/L;
nhw = 4096;
Hw = kaiser(nhw, 8)';
if sinc_use_lut == 1
nharm = 512;
nsin = 4096;
xx = (0:nsin)/nsin - 0.5;
mmm=0;
for mm=1:nharm,
mmm=mmm+1;
bb(mm, :) = sin(mmm*xx*pi);
end;
aa = sin(xx*pi);
end;
sinc_m(mm, find(aa == 0)) = 1;
x = 0.5;
z = -1;
f = fstart;
sqr = 0.0;
c4 = 0;
a = 1;
b = 1;
for n = 1:L,
if x >= 0.5,
x = x - 1;
p = fs/f;
fraq = 1.0/p;
m = fix((p/2.0)) + 1;
saw = 0.0;
c3 = 0.0;
z = -z;
end;
if sinc_use_lut == 1
nn = (x+0.5)*nsin + 1;
ni = fix(nn);
nf = nn - ni;
bbi = (bb(m, ni+1) - bb(m, ni))*nf + bb(m, ni); % Fractional delay (linear interpolation)
aai = (aa(ni+1) - aa(ni))*nf + aa(ni); % Fractional delay (linear interpolation)
if (aai ~= 0)
blit = fraq* bbi / aai * Hw(fix((x+0.5)*nhw)+1);
else
blit = fraq;
end
else
b = sin(m*x*pi);
a = sin(x*pi);
if (a ~= 0)
blit = fraq * b/a * Hw(fix((x+0.5)*nhw)+1);
else
blit = fraq;
end
end
saw = saw + blit;
sqr = sqr + z*blit;
vsaw(n) = 2*(saw - c3);
vsqr(n) = 2*(sqr - 0.5);
vblit(n) = blit;
vc3(n) = b;
x = x + fraq;
c3 = c3 + fraq;
f = f + df;
c4 = c4 + fraq - blit;
vc4(n) = a;
end;
close all
figure;
plot(1:L, vsaw, 1:L, vc4, 1:L, vblit); grid;
figure;
plot(vc4); grid;
figure;
plot(vc3); grid;
if sinc_use_lut == 1
figure;
plot(sinc_m(nharm, :)); grid;
end;
wavwrite(0.5*vc4, fs, 'c4.wav');
wavwrite(0.5*vc3, fs, 'c3.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblit, fs, 'blit.wav');
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function eval_blit()
Nb = 33;
Nos = 1000;
fs = 48000;
f = 440;
fcut = 16000;
P = fs/f
Pi = floor(P)
Pf = fix(Nos*(fs/f - Pi))
x = (0:Nb*Nos-1) - (Nb*Nos-1)/2;
H = sinc(2*fcut/fs.*x/Nos).*Kaiser(Nos*Nb, 8)';
for ii=0:Nos-1,
for jj=0:Nb-1
Hs(ii+1,jj+1) = H(Nos-ii+Nos*jj);
end
end;
%Hs = init_steps(Nb, Nos);
k = 1./sum(Hs');
%k = ones(1, Nb);
y0 = 0;
y1 = 0;
y2 = .5;
ks = 0.002*f/55
ii = 0;
ff = 0;
nn = 1;
jj = Nb;
kk = 1;
for i = 1:32000,
if ii == 0
jj = 1;
kk = ff + 1;
ii = Pi;
ff = ff + Pf;
if ff > (Nos-1)
ff = ff - Nos;
ii = ii + 1;
end
end;
ii = ii - 1;
if jj <= Nb
y0 = y0 + k(kk)*Hs(kk,jj); % - ks*y0;
jj = jj + 1;
end;
y0 = y0 - ks*y0;
y1 = 1 - y0;
y2 = 0.001*y1 + 0.999*y2;
blit(nn) = y1-y2;
nn = nn + 1;
end;
wavwrite(0.7*blit, fs, 'blit.wav');
for ii = 1:Nos
step(ii,:) = k(ii).*filter(Hs(ii,:), 1, [ones(1,Nb)]);
end
close all
plot(1:length(blit), blit, '-o'); grid;
figure
plot(abs(fft(blit))); grid;
figure
plot(step', '-'); grid;
figure
plot(Hs(1,:)', '-+'); grid;
function steps = init_steps(step_width, phase_count)
low_pass = 0.999; % lower values filter more high frequency
high_pass = 0.990; % lower values filter more low frequency
%phase_count = 32; % number of phase offsets to sample band-limited step at
%step_width = 16; % number of samples in each final band-limited step
%steps [phase_count] [step_width]; // would use short for speed in a real program
% Generate master band-limited step by adding sine components of a square wave
master_size = step_width * phase_count;
% master [master_size]; // large; might want to malloc() instead
for i = 0:master_size-1
master(i+1) = 0.5;
end;
gain = 0.5 / 0.777; % adjust normal square wave's amplitude of ~0.777 to 0.5
sine_size = 256 * phase_count + 2;
max_harmonic = sine_size / 2 / phase_count;
for h = 1:2:max_harmonic
amplitude = gain / h;
to_angle = 3.14159265358979323846 * 2 / sine_size * h;
for i = 0:master_size-1
master(i+1) = master(i+1) + sin( (i - master_size / 2) * to_angle ) * amplitude;
end
gain = gain * low_pass;
end
% Sample master step at several phases
for phase = 0:phase_count-1
error = 1.0;
prev = 0.0;
for i = 0:step_width-1
cur = master (i * phase_count + (phase_count - 1 - phase)+1);
delta = cur - prev;
error = error - delta;
prev = cur;
steps (phase+1, i+1) = delta;
end
% each delta should total 1.0
steps (phase+1, step_width / 2) = steps (phase+1, step_width / 2) + error * 0.5;
steps (phase+1, step_width / 2 + 1) = steps (phase+1, step_width / 2 + 1) + error * 0.5;
end
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function eval_blit()
sinc_use_lut = 0
L = 40000;
fs = 48000;
fstart = 8*440;
fend = 8*440;
df = (fend-fstart)/L
nhw = 4096;
Hw = kaiser(nhw, 8)';
max_m = fix((fs/fstart/2.0)) + 1
sinc_table_calc = sinc_use_lut;
if sinc_table_calc == 1
nharm = max_m
nsin = 1024;
xx = (0:nsin)/nsin - 0.5;
mmm=0;
for mm=1:nharm,
mmm=mmm+1;
bb(mm, :) = sin(mmm*xx*pi);
end;
aa = sin(xx*pi);
end;
x = 0.5;
z = -1;
f = fstart;
sqr = 0.0;
saw = 0.0;
tri = 0.0;
a = 1;
b = 1;
for n = 1:L,
if x >= 0.5,
x = x - 1;
p = fs/f;
fraq = 1.0/p;
m = fix((p/2.0)) + 1;
z = -z;
end;
if sinc_use_lut == 1
nn = (x+0.5)*nsin + 1;
ni = fix(nn);
nf = nn - ni;
bbi = (bb(m, ni+1) - bb(m, ni))*nf + bb(m, ni); % Fractional delay (linear interpolation)
aai = (aa(ni+1) - aa(ni))*nf + aa(ni); % Fractional delay (linear interpolation)
if (aai ~= 0)
blit = fraq* bbi / aai * Hw(fix((x+0.5)*nhw)+1);
else
blit = fraq;
end
else
b = sin(m*x*pi);
a = sin(x*pi);
if (a ~= 0)
blit = fraq * b/a * Hw(fix((x+0.5)*nhw)+1);
else
blit = fraq;
end
end
saw = saw + fraq - blit;
sqr = sqr + z*blit;
tri = tri + 2*(sqr-0.5)*fraq;
vtri(n) = tri;
vsaw(n) = saw;
vsqr(n) = 2*(sqr - 0.5);
vblit(n) = blit;
x = x + fraq;
f = f + df;
end;
close all
figure;
plot(1:L, vsaw, 1:L, vblit); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblit, fs, 'blit.wav');
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function eval_blit()
L = 64000;
Nb = 65;
Nos = 8;
fs = 48000;
fstart = 440;
fend = 1760;
df = (fend-fstart)/L
fcut = 16000;
x = (0:Nb*Nos-1) - (Nb*Nos-1)/2;
H = sinc(2*fcut/fs.*x/Nos).*Kaiser(Nos*Nb, 8)';
for ii=0:Nos-1,
for jj=0:Nb-1
Hs(ii+1,jj+1) = H(Nos-ii+Nos*jj);
end
end;
%Hs = init_steps(Nb, Nos);
f = fstart;
k = 1./sum(Hs')
%k = ones(1, Nb);
y0 = 0;
y1 = 0;
y2 = .5;
ks = 0.002*f/55
ii = 0;
ff = 0;
nn = 1;
jj = Nb;
kk = 1;
for i = 1:L,
P = fs/f;
Pi = floor(P);
Pf = fix(Nos*(fs/f - Pi));
if ii == 0
jj = 1;
kk = ff + 1;
ii = Pi;
ff = ff + Pf;
if ff > (Nos-1)
ff = ff - Nos;
ii = ii + 1;
end
end;
ii = ii - 1;
if jj <= Nb
y0 = k(kk)*Hs(kk,jj); % - ks*y0;
jj = jj + 1;
end;
y0 = y0 - ks*y0;
y1 = 1 - y0;
y2 = 0.001*y1 + 0.999*y2;
blit(nn) = y1-y2; % DC removal
nn = nn + 1;
f = f + df;
end;
wavwrite(0.7*blit, fs, 'blit.wav');
for ii = 1:Nos
step(ii,:) = k(ii).*filter(Hs(ii,:), 1, [ones(1,Nb)]);
end
DC = y2
close all
plot(H); grid;
figure
plot(1:length(blit), blit, '-o'); grid;
figure
plot(abs(fft(blit))); grid;
figure
plot(step', '-'); grid;
figure
plot(Hs(1,:)', '-+'); grid;
function steps = init_steps(step_width, phase_count)
low_pass = 0.999; % lower values filter more high frequency
high_pass = 0.990; % lower values filter more low frequency
%phase_count = 32; % number of phase offsets to sample band-limited step at
%step_width = 16; % number of samples in each final band-limited step
%steps [phase_count] [step_width]; // would use short for speed in a real program
% Generate master band-limited step by adding sine components of a square wave
master_size = step_width * phase_count;
% master [master_size]; // large; might want to malloc() instead
for i = 0:master_size-1
master(i+1) = 0.5;
end;
gain = 0.5 / 0.777; % adjust normal square wave's amplitude of ~0.777 to 0.5
sine_size = 256 * phase_count + 2;
max_harmonic = sine_size / 2 / phase_count;
for h = 1:2:max_harmonic
amplitude = gain / h;
to_angle = 3.14159265358979323846 * 2 / sine_size * h;
for i = 0:master_size-1
master(i+1) = master(i+1) + sin( (i - master_size / 2) * to_angle ) * amplitude;
end
gain = gain * low_pass;
end
% Sample master step at several phases
for phase = 0:phase_count-1
error = 1.0;
prev = 0.0;
for i = 0:step_width-1
cur = master (i * phase_count + (phase_count - 1 - phase)+1);
delta = cur - prev;
error = error - delta;
prev = cur;
steps (phase+1, i+1) = delta;
end
% each delta should total 1.0
steps (phase+1, step_width / 2) = steps (phase+1, step_width / 2) + error * 0.5;
steps (phase+1, step_width / 2 + 1) = steps (phase+1, step_width / 2 + 1) + error * 0.5;
end
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function eval_blit()
L = 64000;
Nb = 137;
Nphases = 256;
fs = 48000;
fstart = 110*4;
fend = 110*4;
df = (fend-fstart)/L;
fcut = 16000;
x = (0:Nb*Nphases-1) - (Nb*Nphases-1)/2;
H = sinc(2*fcut/fs.*x/Nphases);%.*Kaiser(Nphases*Nb, 8)';
Hw = Kaiser(Nb, 18)';
for ii=0:Nphases-1,
for jj=0:Nb-1
Hs(ii+1,jj+1) = H(Nphases-ii+Nphases*jj);
end
end;
f = fstart;
Pic = 1;
blit(1:L) = zeros(1, L);
blit_bp(1:L) = zeros(1, L);
pol = 1;
for n = Nb:L,
P = fs/f;
Pi = floor(P);
Pf = 1+fix(Nphases*(P - Pi));
if Pic >= Pi,
blit(n-Nb+1:n) = blit(n-Nb+1:n) + Hs(Pf,:).*Hw;
blit_bp(n-Nb+1:n) = blit_bp(n-Nb+1:n) + pol*Hs(Pf,:).*Hw;
Pic = 0;
pol = -pol;
end;
Pic = Pic + 1;
f = f + df;
end;
mean_blit = 0.0034;
mean_saw = 0.00;
saw(1:L) = zeros(1, L);
sqr(1:L) = zeros(1, L);
y_saw = 0;
y_sqr = 0;
for n = 2:L,
y_saw = y_saw + blit(n)-mean_blit;
y_sqr = y_sqr + blit_bp(n);
saw(n) = -y_saw -1;
sqr(n) = y_sqr;
end;
saw_nodc = filter([1 -1], [1 -0.995], saw);
sqr_nodc = filter([1 -1], [1 -0.995], sqr);
close all;
plot(saw); grid;
figure;
plot(saw_nodc); grid;
wavwrite(0.8*blit, fs, 'blit.wav');
wavwrite(0.7*saw_nodc, fs, 'saw.wav');
wavwrite(0.5*sqr_nodc, fs, 'sqr.wav');
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function eval_blit()
sinc_use_lut = 0
L = 40000;
fs = 48000;
fstart = 110;
fend = 1550;
df = (fend-fstart)/L;
nhw = 4096;
Hw = kaiser(nhw, 8)';
ya = zeros(3,1);
yb = zeros(3,1);
x = 0.5;
z = -1;
f = fstart;
sqr = 0.0;
c4 = 0;
for n = 1:L,
if x >= 0.5,
x = x - 1;
p = fs/f;
fraq = 1.0/p;
m = fix((p/2.0)) + 1;
saw = 0.0;
c3 = 0.0;
z = -z;
ip = 0; % phase of the first output sample in radians
w = f*pi / fs
ba1 = 2.0 * cos(w)
bb1 = 2.0 * cos(w)
end;
if sinc_use_lut == 1
xi = fix((x+0.5)*nsin)+1
if aa(xi) ~= 0
blit = fraq*sinc_m(m, xi) * Hw(fix((x+0.5)*nhw)+1);;
else
blit = fraq;
end
else
b = fraq*sin(m*x*pi);
a = sin(x*pi);
if (a ~= 0)
blit = b/a * Hw(fix((x+0.5)*nhw)+1);
else
blit = fraq;
end
end
saw = saw + blit;
sqr = sqr + z*blit;
vsaw(n) = 2*(saw - c3);
vsqr(n) = 2*(sqr - 0.5);
vblit(n) = blit;
vc3(n) = c3;
x = x + fraq;
c3 = c3 + fraq;
f = f + df;
c4 = c4 + fraq - blit;
vc4(n) = c4;
end;
close all
figure;
plot(1:L, vsaw, 1:L, vc4, 1:L, vblit); grid;
figure;
plot(vblit); grid;
figure;
plot(vc3); grid;
if sinc_use_lut == 1
figure;
plot(sinc_m(nharm, :)); grid;
end;
wavwrite(0.5*vc4, fs, 'c4.wav');
wavwrite(0.5*vc3, fs, 'c3.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblit, fs, 'blit.wav');
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function eval_blit4()
L = 4000;
fs = 48000;
fstart = 110;
fend = 110;
df = (fend-fstart)/L;
nhw = 4096;
Hw = kaiser(nhw, 8)';
ya = zeros(3,1);
yb = zeros(3,1);
x = 0.5;
z = -1;
f = fstart;
sqr = 0.0;
c4 = 0;
for n = 1:L,
if x >= 0.5,
x = x - 1;
p = fs/f;
fraq = 1.0/p;
m = fix((p/2.0)) + 1
saw = 0.0;
c3 = 0.0;
z = -z;
ip = -pi/2; % phase of the first output sample in radians
w = f*pi / fs;
ba1 = 2.0 * cos(w);
bb1 = 2.0 * cos(m*w);
ya(2)=sin(ip-w);
ya(3)=sin(ip-2*w);
yb(2)=sin(ip-m*w);
yb(3)=sin(ip-2*m*w);
end;
ya(1) = ba1*ya(2) - ya(3);
ya(3) = ya(2);
ya(2) = ya(1);
yb(1) = bb1*yb(2) - yb(3);
yb(3) = yb(2);
yb(2) = yb(1);
b = fraq*yb(1);
a = ya(1);
if (a ~= 0)
blit = b/a * Hw(fix((x+0.5)*nhw)+1);
else
blit = fraq;
end
saw = saw + blit;
sqr = sqr + z*blit;
vsaw(n) = 2*(saw - c3);
vsqr(n) = 2*(sqr - 0.5);
vblit(n) = blit;
vc3(n) = b;
x = x + fraq;
c3 = c3 + fraq;
f = f + df;
c4 = c4 + fraq - blit;
vc4(n) = a;
end;
close all
figure;
plot(1:L, vsaw, 1:L, vc4, 1:L, vblit); grid;
figure;
plot(vc4); grid;
figure;
plot(vc3); grid;
wavwrite(0.5*vc4, fs, 'c4.wav');
wavwrite(0.5*vc3, fs, 'c3.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblit, fs, 'blit.wav');
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function eval_hardsync()
nsin = 4096;
nharm_max = 1800;
L = 48000/2;
fs = 48000;
fstart = 440;
fend = 440;
df = (fend-fstart)/L
f2start = 400;
f2end = 400;
df2 = (f2end-f2start)/L
% Calc blep table
nharm = min(fix((fs/min(fstart, f2start)/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm
blitm(mm,:) = sin(xx*(mm-1)*pi)./sin(xx*pi).*Hw';
blitm(mm,(find(isnan(blitm(mm,:))))) = (mm-1);
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
x = 0.0;
x2 = 0.0;
z = 0;
f = fstart;
f2 = f2start;
tri = 0;
saw = 0;
NLG = 2;
h = lagrange(1, 0.35)
startup = 1;
for n = 1:L,
if x >= 1 || startup;
x = 0;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
blep_offset = 0;
blep_gain = 1;
z = ~z;
end;
if x2 >= 1 || startup,
x2 =0;
p2 = fs/f2;
dx2 = 1.0/p2;
m2 = min(fix((p2/2.0)) + 1, nharm_max);
% blep_offset = -(1-(x+0.5));
% blep_gain = x+0.5;
% x = 0;
% z = ~z;
end;
startup = 0;
% BLEP 1
nn = (x+0.0)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep = h(NLG+1)*blepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*blepm(m, max(1, ni-j));
j = j + 1;
end;
% BLEP 2
nn = (x2+0.0)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep2 = h(NLG+1)*blepm(m2, max(1, ni));
j = 1;
for i = NLG:-1:1
blep2 = blep2 + h(i)*blepm(m2, max(1, ni-j));
j = j + 1;
end;
saw = x - blep;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
vsqr(n) = 0.5*(sqr-0.5);
tri = tri + 2*(sqr-0.5)*dx;
vtri(n,1) = sqr;
vtri(n,2) = tri;
vsaw(n,1) = x;
vsaw(n,2) = tri;
vblep(n,1) = x;
vblep(n,2) = blep;
x = x + dx;
f = f + df;
x2 = x2 + dx2;
f2 = f2 + df2;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_hardsync()
nsin = 4096;
nharm_max = 1800;
L = 48000/2;
fs = 48000;
fstart = 440;
fend = 440;
df = (fend-fstart)/L
f2start = 200;
f2end = 600;
df2 = (f2end-f2start)/L
% Calc blep table
nharm = min(fix((fs/fstart/2.0)) + 1, nharm_max)
Hw = kaiser(nsin, 8);
xx = (0:nsin-1)/nsin - 0.5;
for mm=1:nharm
blitm(mm,:) = sin(xx*(mm-1)*pi)./sin(xx*pi).*Hw';
blitm(mm,(find(isnan(blitm(mm,:))))) = (mm-1);
end;
for mm=1:nharm
blepm(mm, :) = cumsum(blitm(mm, :))/nsin;
end;
x = 0.0;
x2 = 0.0;
z = 0;
f = fstart;
f2 = f2start;
tri = 0;
NLG = 2;
h = lagrange(1, 0.35)
startup = 1;
for n = 1:L,
if x >= 1 || startup;
x = x - 1;
p = fs/f;
dx = 1.0/p;
m = min(fix((p/2.0)) + 1, nharm_max);
z = ~z;
end;
if x2 >= 1 || startup,
x2 =0;
p2 = fs/f2;
dx2 = 1.0/p2;
m2 = min(fix((p2/2.0)) + 1, nharm_max);
% blep_offset = -(1-x);
% blep_gain = x;
% x = 0;
% z = ~z;
end;
startup = 0;
nn = (x+0.0)*(nsin-1) + 1;
ni = fix(nn);
nf = nn - ni;
h = lagrange(NLG, nf);
blep = h(NLG+1)*blepm(m, max(1, ni));
j = 1;
for i = NLG:-1:1
blep = blep + h(i)*blepm(m, max(1, ni-j));
j = j + 1;
end;
saw = x - blep;
if (z == 0)
sqr = blep;
else
sqr = 1-blep;
end
vsqr(n) = 0.5*(sqr-0.5);
tri = tri + 2*(sqr-0.5)*dx;
vtri(n) = tri;
vsaw(n,1) = x;
vsaw(n,2) = saw+0.5;
vblep(n,1) = x;
vblep(n,2) = blep;
x = x + dx;
f = f + df;
x2 = x2 + dx2;
f2 = f2 + df2;
end;
close all
plot(1:nsin, blepm(fix(nharm/2), :)); grid;
wavwrite(0.5*vtri, fs, 'tri.wav');
wavwrite(0.5*vsqr, fs, 'sqr.wav');
wavwrite(0.5*vsaw, fs, 'saw.wav');
wavwrite(0.5*vblep, fs, 'blep.wav');
function h = lagrange(N, delay)
%LAGRANGE h=lagrange(N,delay) returns order N FIR
% filter h which implements given delay
% (in samples). For best results,
% delay should be near N/2 +/- 1.
n = 0:N;
h = ones(1,N+1);
for k = 0:N
index = find(n ~= k);
h(index) = h(index) * (delay-k)./ (n(index)-k);
end
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function eval_harmonics(name)
base = exp(1);
ke = 10;
[x, fs, nbits] = wavread(name);
y = (1 - base.^(-ke*fabs(x))) * sign(x);
wavrite(y, fs, nbits,
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function eval_harmonics(name)
base = exp(1);
ke = 2;
[x, fs, nbits] = wavread(name);
y = (1 - base.^(-ke*abs(x))) .* sign(x);
yname = sprintf('out.wav', name);
wavwrite(y*0.8, fs, nbits, yname);
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function paramscale(base, kexp, scenter, pcenter, pmin, pmax)
N = 1000;
slider = (0:N)/N;
p = toParam(base, kexp, scenter, pcenter, pmin, pmax, slider);
s = toSlider(base, kexp, scenter, pcenter, pmin, pmax, p);
subplot (2, 1, 1)
plot (0:N, p); grid; xlabel('param');
subplot (2, 1, 2)
plot (0:N, s); grid; xlabel('slider');
function param = toParam(base, kexp, scenter, pcenter, pmin, pmax, slider)
% pcenter = pmax*scenter + pmin*(1-scenter)
for i=1:length(slider),
s = min(1, max(0, slider(i)));
if (s < scenter)
if (base == 1)
p = pcenter-(pcenter-pmin)*(scenter-s)/scenter;
% p = pcenter-(pcenter-pmin)*(scenter-s)/scenter;
else
p = pcenter-(pcenter-pmin)*(base^(kexp*(scenter-s)/scenter)-1)/(base^kexp-1);
% p = pcenter-(pcenter-pmin)*(pow(base,kexp*(scenter-s)/scenter)-1)/(pow(base,kexp)-1);
end
else
if (base == 1)
p = pcenter+(pmax-pcenter)*(-scenter+s)/(1-scenter);
% p = pcenter+(pmax-pcenter)*(-scenter+s)/(1-scenter);
else
p = pcenter+(pmax-pcenter)*(base^(kexp*(-scenter+s)/(1-scenter))-1)/(base^kexp-1);
% p = pcenter+(pmax-pcenter)*(pow(base,kexp*(-scenter+s)/(1-scenter))-1)/(pow(base,kexp)-1);
end;
end
param(i) = p;
end
function slider = toSlider(base, kexp, scenter, pcenter, pmin, pmax, param)
%pcenter = pmax*scenter + pmin*(1-scenter);
for i=1:length(param),
p = param(i);
if (p < pcenter)
if (base == 1)
s = (-pmin+p)*scenter/(pcenter-pmin);
% s = (-pmin+p)*scenter/(pcenter-pmin);
else
s = scenter*(log(base)*kexp-log(-(-pcenter*base^kexp+pmin+p*base^kexp-p)/(pcenter-pmin)))/log(base)/kexp;
% s = scenter*(log(base)*kexp-log(-(-pcenter*pow(base,kexp)+pmin+p*pow(base,kexp)-p)/(pcenter-pmin)))/log(base)/kexp;
end
else
if (base == 1)
s = (pcenter-scenter*pmax-p+scenter*p)/(-pmax+pcenter);
% s = (pcenter-scenter*pmax-p+scenter*p)/(-pmax+pcenter);
else
s = (kexp*log(base)*scenter+log(-(-pcenter*base^kexp+pmax+p*base^kexp-p)/(-pmax+pcenter))-log(-(-pcenter*base^kexp+pmax+p*base^kexp-p)/(-pmax+pcenter))*scenter)/log(base)/kexp;
% s = (kexp*log(base)*scenter+log(-(-pcenter*pow(base,kexp)+pmax+p*pow(base,kexp)-p)/(-pmax+pcenter))-log(-(-pcenter*pow(base,kexp)+pmax+p*pow(base,kexp)-p)/(-pmax+pcenter))*scenter)/log(base)/kexp;
end
end
slider(i) = s;
end
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function paramscale(base, kexp, scenter, pcenter, pmin, pmax)
N = 1000;
slider = (0:N)/N;
p = toParam(base, kexp, scenter, pcenter, pmin, pmax, slider);
s = toSlider(base, kexp, scenter, pcenter, pmin, pmax, p);
subplot (2, 1, 1)
plot (slider, p); grid; xlabel('toParam(s)');
subplot (2, 1, 2)
plot (slider, s); grid; xlabel('toSlider(p)');
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function param = toParam(base, kexp, scenter, pcenter, pmin, pmax, slider)
if ((pcenter < pmin) || (pcenter > pmax))
pcenter = pmax*scenter + pmin*(1-scenter);
end
for i=1:length(slider),
s = min(1, max(0, slider(i)));
if (s < scenter)
if (base == 1)
p = pcenter-(pcenter-pmin)*(scenter-s)/scenter;
% p = pcenter-(pcenter-pmin)*(scenter-s)/scenter;
else
p = pcenter-(pcenter-pmin)*(base^(kexp*(scenter-s)/scenter)-1)/(base^kexp-1);
% p = pcenter-(pcenter-pmin)*(pow(base,kexp*(scenter-s)/scenter)-1)/(pow(base,kexp)-1);
end
else
if (base == 1)
p = pcenter+(pmax-pcenter)*(-scenter+s)/(1-scenter);
% p = pcenter+(pmax-pcenter)*(-scenter+s)/(1-scenter);
else
p = pcenter+(pmax-pcenter)*(base^(kexp*(-scenter+s)/(1-scenter))-1)/(base^kexp-1);
% p = pcenter+(pmax-pcenter)*(pow(base,kexp*(-scenter+s)/(1-scenter))-1)/(pow(base,kexp)-1);
end;
end
param(i) = p;
end
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function slider = toSlider(base, kexp, scenter, pcenter, pmin, pmax, param)
if ((pcenter < pmin) || (pcenter > pmax))
pcenter = pmax*scenter + pmin*(1-scenter);
end
for i=1:length(param),
p = param(i);
if (p < pcenter)
if (base == 1)
s = (-pmin+p)*scenter/(pcenter-pmin);
% s = (-pmin+p)*scenter/(pcenter-pmin);
else
s = scenter*(log(base)*kexp-log(-(-pcenter*base^kexp+pmin+p*base^kexp-p)/(pcenter-pmin)))/log(base)/kexp;
% s = scenter*(log(base)*kexp-log(-(-pcenter*pow(base,kexp)+pmin+p*pow(base,kexp)-p)/(pcenter-pmin)))/log(base)/kexp;
end
else
if (base == 1)
s = (pcenter-scenter*pmax-p+scenter*p)/(-pmax+pcenter);
% s = (pcenter-scenter*pmax-p+scenter*p)/(-pmax+pcenter);
else
s = (kexp*log(base)*scenter+log(-(-pcenter*base^kexp+pmax+p*base^kexp-p)/(-pmax+pcenter))-log(-(-pcenter*base^kexp+pmax+p*base^kexp-p)/(-pmax+pcenter))*scenter)/log(base)/kexp;
% s = (kexp*log(base)*scenter+log(-(-pcenter*pow(base,kexp)+pmax+p*pow(base,kexp)-p)/(-pmax+pcenter))-log(-(-pcenter*pow(base,kexp)+pmax+p*pow(base,kexp)-p)/(-pmax+pcenter))*scenter)/log(base)/kexp;
end
end
slider(i) = s;
end