comparison SimpleCepstrum.cpp @ 27:44bb93cae288

Change peak-to-next-peak ratio to a difference (because difference of peaks in log values don't vary with signal amplification)

     d.description = "Return the proportion of total energy that is found in the bins around the peak bin (as far as the nearest local minima), within the specified range of the cepstrum";
     m_ppOutput = n++;
     outputs.push_back(d);
 
     d.identifier = "peak_to_second_peak";
-    d.name = "Peak to second-peak ratio";
-    d.unit = "";
-    d.description = "Return the ratio of the value found in the peak bin within the specified range of the cepstrum, to the value found in the next highest peak";
+    d.name = "Peak to second-peak difference";
+    d.unit = "";
+    d.description = "Return the difference between the value found in the peak bin within the specified range of the cepstrum, and that found in the next highest peak";
     m_pkoOutput = n++;
     outputs.push_back(d);
 
     d.identifier = "total";
     d.name = "Total energy";

     pv.values.push_back(maxval);
     fs[m_pvOutput].push_back(pv);
 
     Feature pko;
     if (nextPeakVal != 0.0) {
-        pko.values.push_back(maxval / nextPeakVal);
+        pko.values.push_back(maxval - nextPeakVal);
     } else {
         pko.values.push_back(0.0);
     }
     fs[m_pkoOutput].push_back(pko);