BlackmanHarrisNuttall.java (654B)
1 package be.tarsos.dsp.util.fft; 2 3 /** 4 * @author joren 5 * See https://mgasior.web.cern.ch/mgasior/pap/FFT_resol_note.pdf 6 */ 7 public class BlackmanHarrisNuttall extends WindowFunction { 8 float c0 = 0.355768f; 9 float c1 = 0.487396f; 10 float c2 = 0.144232f; 11 float c3 = 0.012604f; 12 13 @Override 14 protected float value(int length, int index) { 15 16 float sum = 0; 17 18 sum += c0 * Math.cos((TWO_PI * 0 * index ) / (float) (length)) ; 19 sum += c1 * Math.cos((TWO_PI * 1 * index ) / (float) (length)); 20 sum += c2 * Math.cos((TWO_PI * 2 * index ) / (float) (length)); 21 sum += c3 * Math.cos((TWO_PI * 3 * index ) / (float) (length)); 22 23 return sum; 24 } 25 26 }