annotate dsp/onsets/PeakPicking.h @ 321:f1e6be2de9a5

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

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    QM DSP Library

    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
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

// PeakPicking.h: interface for the PeakPicking class.
//
//////////////////////////////////////////////////////////////////////

#ifndef PEAKPICKING_H
#define PEAKPICKING_H

#include "maths/MathUtilities.h"
#include "maths/MathAliases.h"
#include "dsp/signalconditioning/DFProcess.h"


struct PPWinThresh
{
    unsigned int pre;
    unsigned int  post;

    PPWinThresh(unsigned int x, unsigned int y) :
        pre(x),
        post(y)
    {
    }
};

struct QFitThresh
{
    double a;
    double b;
    double c;

    QFitThresh(double x, double y, double z) :
        a(x),
        b(y),
        c(z)
    {
    }
};

struct PPickParams
{
    unsigned int length; //Detection FunctionLength
    double tau; // time resolution of the detection function
    unsigned int alpha; //alpha-norm parameter
    double cutoff;//low-pass Filter cutoff freq
    unsigned int LPOrd; // low-pass Filter order
    double* LPACoeffs; //low pass Filter den coefficients
    double* LPBCoeffs; //low pass Filter num coefficients
    PPWinThresh WinT;//window size in frames for adaptive thresholding [pre post]:
    QFitThresh QuadThresh;
    float delta; //delta threshold used as an offset when computing the smoothed detection function

    PPickParams() :
        length(0),
        tau(0),
        alpha(0),
        cutoff(0),
        LPOrd(0),
        LPACoeffs(NULL),
        LPBCoeffs(NULL),
        WinT(0,0),
        QuadThresh(0,0,0),
        delta(0)
    {
    }
};

class PeakPicking  
{
public:
    PeakPicking( PPickParams Config );
    virtual ~PeakPicking();
	
    void process( double* src, unsigned int len, vector<int> &onsets  );


private:
    void initialise( PPickParams Config  );
    void deInitialise();
    int  quadEval( vector<double> &src, vector<int> &idx );
	
    DFProcConfig m_DFProcessingParams;

    unsigned int m_DFLength ;
    double Qfilta ;
    double Qfiltb;
    double Qfiltc;


    double* m_workBuffer;
	
    DFProcess*	m_DFSmoothing;
};

#endif