private IEnumerable <ComplexCarrierTone> CreateSideBands(
double freqLB,
double freqUB,
int count,
AmplitudeDistribution distribution)
{
double freqRatio = Math.Pow((freqUB / freqLB), 1.0 / (count - 1));
if (double.IsNaN(freqRatio) || double.IsInfinity(freqRatio))
{
freqRatio = 1.0;
}
double freq = freqLB;
for (int carrierTone = 0; carrierTone < count; carrierTone++)
{
yield return(new ComplexCarrierTone(
frequency: freq,
amplitude: Complex64.FromPolarCoordinates(
magnitude: GetFactor(distribution, freq) * CustomRandom.RayleighDistribution(randomizer.NextDouble()),
phase: 2.0 * Math.PI * randomizer.NextDouble())));
freq *= freqRatio;
}
}
public static string ToDisplayName(this AmplitudeDistribution distribution)
{
switch (distribution)
{
case AmplitudeDistribution.Unitary: return("Unitary");
case AmplitudeDistribution.FlatRandom: return("Random (Flat)");
case AmplitudeDistribution.Rayleigh: return("Random (Rayleigh)");
default:
UnityEngine.Debug.LogError($"Unexpected AmplitudeDistribution: {distribution}");
return("");
}
}
public static double GetFactor(this AmplitudeDistribution amplitudeDistribution, Random randomizer)
{
switch (amplitudeDistribution)
{
case AmplitudeDistribution.Unitary: return(1.0);
case AmplitudeDistribution.FlatRandom: return(randomizer.NextDouble());
case AmplitudeDistribution.Rayleigh: return(CustomRandom.RayleighDistribution(randomizer.NextDouble()));
default:
UnityEngine.Debug.LogError($"Unexpected AmplitudeDistribution: {amplitudeDistribution}");
return(1.0);
}
}
//This function includes an extra factors of sqrt(f) to account for the inherent 1/sqrt(f) from
//the exponential distribution of frequencies
private double GetFactor(AmplitudeDistribution amplitudeDistribution, double frequency)
{
switch (amplitudeDistribution)
{
case AmplitudeDistribution.Violet: return(frequency * Math.Sqrt(frequency));
case AmplitudeDistribution.Blue: return(frequency);
case AmplitudeDistribution.White: return(Math.Sqrt(frequency));
case AmplitudeDistribution.Pink: return(1.0);
case AmplitudeDistribution.Brown: return(1.0 / Math.Sqrt(frequency));
default:
Debug.LogError($"Unexpected AmplitudeFactor: {amplitudeDistribution}");
return(1.0);
}
}
public STMAudioClip(
double duration,
double freqLB,
double freqUB,
int frequencyCount,
double modulationDepth,
double spectralModulationRate,
double temporalModulationRate,
RippleDirection rippleDirection,
AmplitudeDistribution distribution,
Random randomizer = null)
{
if (randomizer == null)
{
randomizer = new Random(CustomRandom.Next());
}
this.randomizer = randomizer;
carrierToneGenerator = CreateSideBands(freqLB, freqUB, frequencyCount, distribution);
sideBandGenerator = ExpCarrierToneSideBands;
this.modulationDepth = modulationDepth;
this.temporalModulationRate = temporalModulationRate;
switch (rippleDirection)
{
case RippleDirection.Up:
this.spectralModulationRate = spectralModulationRate;
break;
case RippleDirection.Down:
this.spectralModulationRate = -spectralModulationRate;
break;
default:
Debug.LogError($"Unexpected RippleDirection: {rippleDirection}");
break;
}
_channelSamples = (int)Math.Ceiling(duration * SamplingRate);
}
public AnalyticNoiseStream(
double rms,
double freqLB,
double freqUB,
int frequencyCount,
AmplitudeDistribution distribution,
Random randomizer = null)
{
if (randomizer == null)
{
randomizer = new Random(CustomRandom.Next());
}
this.randomizer = randomizer;
this.rms = rms;
this.freqLB = freqLB;
this.freqUB = freqUB;
this.frequencyCount = frequencyCount;
this.distribution = distribution;
}
public NoiseAudioClip(
double duration,
double rms,
double freqLB,
double freqUB,
int frequencyCount,
AmplitudeDistribution distribution,
Random randomizer = null)
{
if (randomizer == null)
{
randomizer = new Random(CustomRandom.Next());
}
this.randomizer = randomizer;
this.rms = rms;
this.freqLB = freqLB;
this.freqUB = freqUB;
this.frequencyCount = frequencyCount;
this.distribution = distribution;
_channelSamples = (int)Math.Ceiling(duration * SamplingRate);
}
