comparison dsp/keydetection/GetKeyMode.cpp @ 73:dcb555b90924

* Key detector: when returning key strengths, use the peak value of the
  three underlying chromagram correlations (from 36-bin chromagram)
  corresponding to each key, instead of the mean.
  Rationale: This is the same method as used when returning the key value,
  and it's nice to have the same results in both returned value and plot.
  The peak performed better than the sum with a simple test set of triads,
  so it seems reasonable to change the plot to match the key output rather
  than the other way around.

* FFT: kiss_fftr returns only the non-conjugate bins, synthesise the rest
  rather than leaving them (perhaps dangerously) undefined.  Fixes an
  uninitialised data error in chromagram that could cause garbage results
  from key detector.

* Constant Q: remove precalculated values again, I reckon they're not
  proving such a good tradeoff.

     // Move bins such that the centre of the base note is in the
     // middle of its three bins :
     // Added 21.11.07 by Chris Sutton based on debugging with Katy
     // Noland + comparison with Matlab equivalent.
     MathUtilities::circShift( m_ChrPointer, m_BPO, 1);
-
 /*
-  std::cout << "raw chroma: ";
-  for (int ii = 0; ii < m_BPO; ++ii) {
-  std::cout << m_ChrPointer[ii] << " ";
-  }
-  std::cout << std::endl;
+    std::cout << "raw chroma: ";
+    for (int ii = 0; ii < m_BPO; ++ii) {
+      if (ii % (m_BPO/12) == 0) std::cout << "\n";
+        std::cout << m_ChrPointer[ii] << " ";
+    }
+    std::cout << std::endl;
 */
     // populate hpcp values;
     int cbidx;
     for( j = 0; j < m_BPO; j++ )
     {

         m_keyStrengths[k] = 0;
     }
 
     for( k = 0; k < m_BPO*2; k++ )
     {
-        m_keyStrengths[k/(m_BPO/12)] += m_Keys[k];
+        int idx = k / (m_BPO/12);
+        int rem = k % (m_BPO/12);
+        if (rem == 0 || m_Keys[k] > m_keyStrengths[idx]) {
+            m_keyStrengths[idx] = m_Keys[k];
+        }
+
+//        m_keyStrengths[k/(m_BPO/12)] += m_Keys[k];
     }
 
 /*
   std::cout << "raw keys: ";
   for (int ii = 0; ii < 2*m_BPO; ++ii) {
-  std::cout << m_Keys[ii] << " ";
+      if (ii % (m_BPO/12) == 0) std::cout << "\n";
+      std::cout << m_Keys[ii] << " ";
+  }
+  std::cout << std::endl;
+
+  std::cout << "key strengths: ";
+  for (int ii = 0; ii < 24; ++ii) {
+      if (ii % 6 == 0) std::cout << "\n";
+      std::cout << m_keyStrengths[ii] << " ";
   }
   std::cout << std::endl;
 */
     double dummy;
     // '1 +' because we number keys 1-24, not 0-23.
     key = 1 + (int)ceil( (double)MathUtilities::getMax( m_Keys, 2* m_BPO, &dummy )/3 );
 
-//	std::cout << "key pre-sorting: " << key << std::endl;
+//    std::cout << "key pre-sorting: " << key << std::endl;
 
 
     //Median filtering
 
     // track Median buffer initial filling

   std::cout << std::endl;
 */
     int sortlength = m_MedianBufferFilling;
     int midpoint = (int)ceil((double)sortlength/2);
 
+//  std::cout << "midpoint = " << midpoint << endl;
+
     if( midpoint <= 0 )
         midpoint = 1;
 
     key = m_SortedBuffer[midpoint-1];
+
+// std::cout << "returning key = " << key << endl;
 
     return key;
 }