protected virtual void UpdateFrequencyMapping()
{
_maximumFrequencyIndex = Math.Min(AudioDelegations.FftInxAcquired(MaximumFrequency) + 1, _maxFftIndex);
_minimumFrequencyIndex = Math.Min(AudioDelegations.FftInxAcquired(MinimumFrequency), _maxFftIndex);
int actualResolution = SpectrumResolution;
int indexCount = _maximumFrequencyIndex - _minimumFrequencyIndex;
double linearIndexBucketSize = Math.Round(indexCount / (double)actualResolution, 3);
_spectrumIndexMax = _spectrumIndexMax.CheckBuffer(actualResolution, true);
_spectrumLogScaleIndexMax = _spectrumLogScaleIndexMax.CheckBuffer(actualResolution, true);
double maxLog = Math.Log(actualResolution, actualResolution);
for (int i = 1; i < actualResolution; i++)
{
int logIndex =
(int)((maxLog - Math.Log((actualResolution + 1) - i, (actualResolution + 1))) * indexCount) +
_minimumFrequencyIndex;
_spectrumIndexMax[i - 1] = _minimumFrequencyIndex + (int)(i * linearIndexBucketSize);
_spectrumLogScaleIndexMax[i - 1] = logIndex;
}
if (actualResolution > 0)
{
_spectrumIndexMax[_spectrumIndexMax.Length - 1] =
_spectrumLogScaleIndexMax[_spectrumLogScaleIndexMax.Length - 1] = _maximumFrequencyIndex;
}
}
public IEnumerable <Point3D> CreateWave()
{
//UpdateFrequencyMapping();
float[] fftBuffer = new float[(int)FftSize];
fftBuffer = AudioDelegations.FftAcquired();
//get the fft result from the spectrum provider
SpectrumPointData[] spectrumPoints = CalculateSpectrumPoints(MaxOffset, fftBuffer);
return(GeneratePoints(spectrumPoints, MaxHeight));
}
