public void GetMidiCodes(int offset, int fftSize = 4096, int maxFreq = 5000)
{
AudioClip clip;
float[] real, im, window;
FloatFFT fft;
string assetPath;
float binWidth;
List <FFTBinInfo> binInfos;
int i;
real = new float[fftSize];
im = new float[fftSize];
window = new float[fftSize];
GATMaths.MakeHammingWindow(window);
fft = new FloatFFT();
fft.init(( uint )Mathf.Log(fftSize, 2));
binWidth = ( float )_sampleRate / fftSize;
int maxBin = ( int )(( float )maxFreq / binWidth);
foreach (GATSampleInfo info in _sampleInfos)
{
assetPath = AssetDatabase.GUIDToAssetPath(info.GUID);
clip = AssetDatabase.LoadAssetAtPath(assetPath, typeof(AudioClip)) as AudioClip;
if (clip.channels > 1)
{
throw new GATException("Get Midi Codes is a beta feature only available for mono clips");
}
clip.GetData(real, offset);
System.Array.Clear(im, 0, im.Length);
fft.run(real, im);
for (i = 0; i < maxBin; i++)
{
real[i] = Mathf.Sqrt(real[i] * real[i] + im[i] * im[i]);
}
binInfos = FFTBinInfo.GetLowerMaxBins(real, 0, maxBin, binWidth, .2f);
info.MidiCode = binInfos[binInfos.Count - 1].GetMidiCode();
}
SortByMidiCode();
}
public static List <FFTBinInfo> GetLowerMaxBins(float[] magnitudes, int fromIndex, int toIndex, float binFrequencyWidth, float magThresholdRatio)
{
List <FFTBinInfo> maxBins = new List <FFTBinInfo>();
FFTBinInfo binInfo;
int maxIndex;
float magThreshold;
fromIndex++;
toIndex--;
maxIndex = GATMaths.GetIndexOfMaxValue(magnitudes, fromIndex, toIndex);
binInfo = new FFTBinInfo(magnitudes, maxIndex, binFrequencyWidth);
maxBins.Add(binInfo);
magThreshold = binInfo.InterpolatedMagnitude * magThresholdRatio;
while (true)
{
toIndex = binInfo.BinIndex - 1;
if (toIndex - fromIndex < 3)
{
break;
}
maxIndex = GATMaths.GetIndexOfMaxValue(magnitudes, fromIndex, toIndex);
binInfo = new FFTBinInfo(magnitudes, maxIndex, binFrequencyWidth);
if (binInfo.InterpolatedMagnitude < magThreshold)
{
break;
}
maxBins.Add(binInfo);
}
return(maxBins);
}
public static List<FFTBinInfo> GetLowerMaxBins( float[] magnitudes, int fromIndex, int toIndex, float binFrequencyWidth, float magThresholdRatio )
{
List< FFTBinInfo > maxBins = new List< FFTBinInfo >();
FFTBinInfo binInfo;
int maxIndex;
float magThreshold;
fromIndex ++;
toIndex --;
maxIndex = GATMaths.GetIndexOfMaxValue( magnitudes, fromIndex, toIndex );
binInfo = new FFTBinInfo( magnitudes, maxIndex, binFrequencyWidth );
maxBins.Add( binInfo );
magThreshold = binInfo.InterpolatedMagnitude * magThresholdRatio;
while( true )
{
toIndex = binInfo.BinIndex - 1;
if( toIndex - fromIndex < 3 )
break;
maxIndex = GATMaths.GetIndexOfMaxValue( magnitudes, fromIndex, toIndex );
binInfo = new FFTBinInfo( magnitudes, maxIndex, binFrequencyWidth );
if( binInfo.InterpolatedMagnitude < magThreshold )
break;
maxBins.Add( binInfo );
}
return maxBins;
}
