diff dsp/signalconditioning/DFProcess.cpp @ 96:88f3cfcff55f

A threshold (delta) is added in the peak picking parameters structure (PPickParams). It is used as an offset when computing the smoothed detection function. A constructor for the structure PPickParams is also added to set the parameters to 0 when a structure instance is created. Hence programmes using the peak picking parameter structure and which do not set the delta parameter (e.g. QM Vamp note onset detector) won't be affected by the modifications.

Functions modified:
- dsp/onsets/PeakPicking.cpp
- dsp/onsets/PeakPicking.h
- dsp/signalconditioning/DFProcess.cpp
- dsp/signalconditioning/DFProcess.h

--- a/dsp/signalconditioning/DFProcess.cpp	Tue Apr 05 13:48:18 2011 +0100
+++ b/dsp/signalconditioning/DFProcess.cpp	Mon Jun 20 19:01:48 2011 +0100
@@ -6,6 +6,14 @@
     Centre for Digital Music, Queen Mary, University of London.
     This file 2005-2006 Christian Landone.
 
+    Modifications:
+
+    - delta threshold
+    Description: add delta threshold used as offset in the smoothed
+    detection function
+    Author: Mathieu Barthet
+    Date: June 2010
+
     This program is free software; you can redistribute it and/or
     modify it under the terms of the GNU General Public License as
     published by the Free Software Foundation; either version 2 of the
@@ -57,7 +65,10 @@
     m_FilterConfigParams.ACoeffs = Config.LPACoeffs;
     m_FilterConfigParams.BCoeffs = Config.LPBCoeffs;
 	
-    m_FiltFilt = new FiltFilt( m_FilterConfigParams );	
+    m_FiltFilt = new FiltFilt( m_FilterConfigParams );
+	
+    //add delta threshold
+    m_Delta = Config.Delta;
 }
 
 void DFProcess::deInitialise()
@@ -146,7 +157,9 @@
 
     for( i = 0; i < m_length; i++ )
     {
-	val = src[ i ] - scratch[ i ];// - 0.033;
+	//add a delta threshold used as an offset when computing the smoothed detection function
+	//(helps to discard noise when detecting peaks)	
+	val = src[ i ] - scratch[ i ] - m_Delta;
 		
 	if( m_isMedianPositive )
 	{