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Big Double/Denormalization Update

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This commit is contained in:
Christopher Johnson 2022-02-26 14:23:03 -05:00
parent 47e16fec36
commit 54fd8c7a18
3302 changed files with 52490 additions and 63509 deletions
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45
plugins/MacAU/PyewacketMono/PyewacketMono.cpp
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@ -174,7 +174,7 @@ ComponentResult PyewacketMono::Initialize()
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
void PyewacketMono::PyewacketMonoKernel::Reset()
{
fpNShape = 0.0;
fpd = 1.0; while (fpd < 16386) fpd = rand()*UINT32_MAX;
chase = 1.0;
lastrectifier = 0.0;
}
@ -196,10 +196,10 @@ void PyewacketMono::PyewacketMonoKernel::Process( const Float32 *inSourceP,
overallscale *= GetSampleRate();
if (overallscale < 0.1) overallscale = 1.0;
//insanity check
long double fpOld = 0.618033988749894848204586; //golden ratio!
long double fpNew = 1.0 - fpOld;
long double inputSample;
long double drySample;
double fpOld = 0.618033988749894848204586; //golden ratio!
double fpNew = 1.0 - fpOld;
double inputSample;
double drySample;
Float64 bridgerectifier;
Float64 temprectifier;
Float64 inputSense;
@ -217,30 +217,7 @@ void PyewacketMono::PyewacketMonoKernel::Process( const Float32 *inSourceP,
while (nSampleFrames-- > 0) {
inputSample = *sourceP;
if (inputSample<1.2e-38 && -inputSample<1.2e-38) {
static int noisesource = 0;
//this declares a variable before anything else is compiled. It won't keep assigning
//it to 0 for every sample, it's as if the declaration doesn't exist in this context,
//but it lets me add this denormalization fix in a single place rather than updating
//it in three different locations. The variable isn't thread-safe but this is only
//a random seed and we can share it with whatever.
noisesource = noisesource % 1700021; noisesource++;
int residue = noisesource * noisesource;
residue = residue % 170003; residue *= residue;
residue = residue % 17011; residue *= residue;
residue = residue % 1709; residue *= residue;
residue = residue % 173; residue *= residue;
residue = residue % 17;
double applyresidue = residue;
applyresidue *= 0.00000001;
applyresidue *= 0.00000001;
inputSample = applyresidue;
//this denormalization routine produces a white noise at -300 dB which the noise
//shaping will interact with to produce a bipolar output, but the noise is actually
//all positive. That should stop any variables from going denormal, and the routine
//only kicks in if digital black is input. As a final touch, if you save to 24-bit
//the silence will return to being digital black again.
}
if (fabs(inputSample)<1.18e-23) inputSample = fpd * 1.18e-17;
@ -280,11 +257,11 @@ void PyewacketMono::PyewacketMonoKernel::Process( const Float32 *inSourceP,
inputSample *= outputGain;
}
//32 bit dither, made small and tidy.
int expon; frexpf((Float32)inputSample, &expon);
long double dither = (rand()/(RAND_MAX*7.737125245533627e+25))*pow(2,expon+62);
inputSample += (dither-fpNShape); fpNShape = dither;
//end 32 bit dither
//begin 32 bit floating point dither
int expon; frexpf((float)inputSample, &expon);
fpd ^= fpd << 13; fpd ^= fpd >> 17; fpd ^= fpd << 5;
inputSample += ((double(fpd)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2,expon+62));
//end 32 bit floating point dither
*destP = inputSample;