public static void Windowing(double[] data, DataWindowType type)
{
double[] window = GetDataWindow(type, data.Length);
for (int i = data.Length; --i >= 0;)
{
data[i] *= window[i];
}
}
public static double[] GetDataWindow(DataWindowType type, int size)
{
double[] Table = new double[size];
Table = new double[size];
double h = 2 * Math.PI / (size - 1);
switch (type)
{
case DataWindowType.Box:
for (int i = size; --i >= 0;)
{
Table[i] = 1;
}
break;
case DataWindowType.Hanning:
for (int i = size; --i >= 0;)
{
Table[i] = 0.50 - 0.50 * Math.Cos(h * i);
}
break;
case DataWindowType.Hamming:
for (int i = size; --i >= 0;)
{
Table[i] = 0.54 - 0.46 * Math.Cos(h * i);
}
break;
case DataWindowType.Blackman:
for (int i = size; --i >= 0;)
{
Table[i] = 0.42 - 0.50 * Math.Cos(h * i) + 0.08 * Math.Cos(2 * h * i);
}
break;
case DataWindowType.Parzen:
for (int i = size; --i >= 0;)
{
Table[i] = 1.0 - Math.Abs((i * 2 - (size - 1)) / (double)(size + 1));
}
break;
case DataWindowType.Welch:
for (int i = size; --i >= 0;)
{
Table[i] = 1.0 - Mt.Sq((i * 2 - (size - 1)) / (double)(size + 1));
}
break;
}
//double c = Math.Sqrt(n / Table.Sum(x => Sq(x)));
//for (int i = n; --i >= 0; ) Table[i] *= c;
return(Table);
}
