void YSE::DSP::FastFadeIn(YSE::DSP::buffer & s, UInt length) {
Clamp(length, 1u, s.getLength());
Flt step = 1.0f / static_cast<Flt>(length);
Flt multiplier = 0.0f;
Flt * ptr = s.getPtr();
for (UInt i = 0; i < length; i++) {
*ptr++ *= multiplier;
multiplier += step;
}
}
void YSE::DSP::FastFadeOut(YSE::DSP::buffer & s, UInt length) {
Clamp(length, 1u, s.getLength());
Flt step = 1.0f / static_cast<Flt>(length);
Flt multiplier = 1.0f;
Flt * ptr = s.getPtr();
for (UInt i = 0; i < length; i++) {
*ptr++ *= multiplier;
multiplier -= step;
}
UInt leftOvers = s.getLength() - length;
while (leftOvers--) *ptr++ = 0.0f;
}
void YSE::DSP::ChangeGain(YSE::DSP::buffer & s, Flt currentGain, Flt newGain, UInt length) {
if (currentGain == newGain) {
s *= newGain;
return;
}
Clamp(length, 1u, s.getLength());
Flt step = (newGain - currentGain) / static_cast<Flt>(length);
Flt multiplier = currentGain;
Flt * ptr = s.getPtr();
for (UInt i = 0; i < length; i++) {
*ptr++ *= multiplier;
multiplier += step;
}
UInt leftOvers = s.getLength() - length;
for (; leftOvers > 7; leftOvers -= 8, ptr += 8) {
ptr[0] *= newGain; ptr[1] *= newGain; ptr[2] *= newGain; ptr[3] *= newGain;
ptr[4] *= newGain; ptr[5] *= newGain; ptr[6] *= newGain; ptr[7] *= newGain;
}
while (leftOvers--) *ptr++ *= newGain;
}
void YSE::DSP::readInterpolated(YSE::DSP::buffer & ctrl, YSE::DSP::buffer& out, YSE::DSP::buffer & buffer, UInt &pos) {
Flt * input = ctrl.getPtr();
Flt * output = out.getPtr();
Int n = ctrl.getLength();
Int nsamps = buffer.getLength();
Flt limit = nsamps - n - 1.0f;
Flt fn = n - 1.0f;
Flt * vp = buffer.getPtr();
Flt *bp = nullptr;
Flt *wp = vp + pos;
while (n--) {
Flt delsamps = SAMPLERATE * *input++, frac;
Int idelsamps;
Flt a, b, c, d, cminusb;
if (delsamps < 1.00001f) delsamps = 1.00001f;
if (delsamps > limit) delsamps = limit;
delsamps += fn;
fn = fn - 1.0f;
idelsamps = (Int)delsamps;
frac = delsamps - static_cast<Flt>(idelsamps);
bp = wp - idelsamps;
if (bp < vp + 4) bp += nsamps;
d = bp[-3];
c = bp[-2];
b = bp[-1];
a = bp[0];
cminusb = c - b;
*output++ = b + frac * (
cminusb - 0.1666667f * (1.0f - frac) * (
(d - a - 3.0f * cminusb) * frac + (d + 2.0f * a - 3.0f * b)
)
);
}
pos = (UInt)(bp - vp);
}
void YSE::DSP::fftStats::operator()(YSE::DSP::buffer & real, YSE::DSP::buffer & imaginary) {
if (real.getLength() != imaginary.getLength()) {
assert(false);
}
int n = real.getLength();
int n2 = (n >> 1);
if (n < 4) {
assert(false);
return;
}
Flt * inReal = real.getPtr();
Flt * inImag = imaginary.getPtr();
Flt * freq = frequencies.getPtr();
Flt * amp = amplitudes.getPtr();
Flt lastReal = 0, currentReal = inReal[0], nextReal = inReal[1];
Flt lastImag = 0, currentImag = inImag[0], nextImag = inImag[1];
int m = n2 + 1;
Flt fbin = 1, oneOverN2 = 1.f / ((Flt)n2 * (Flt)n2);
inReal += 2;
inImag += 2;
*amp++ = *freq++ = 0;
n2 -= 2;
while (n2--) {
Flt re, im, pow, fr;
lastReal = currentReal;
currentReal = nextReal;
nextReal = *inReal++;
lastImag = currentImag;
currentImag = nextImag;
nextImag = *inImag++;
re = currentReal - 0.5f * (lastReal + nextReal);
im = currentImag - 0.5f * (lastImag + nextImag);
pow = re * re + im * im;
if (pow > 1e-19) {
Flt detune = ((lastReal + nextReal) * re + (lastImag - nextImag) * im) / (2.f * pow);
if (detune > 2 || detune < -2) fr = pow = 0;
else fr = fbin + detune;
}
else {
fr = pow = 0;
}
*freq++ = fr;
*amp++ = oneOverN2 * pow;
fbin += 1.f;
}
while (m--) *amp++ = *freq++ = 0;
YSE::DSP::sqrtFunc(frequencies.getPtr(), frequencies.getPtr(), n >> 1);
}