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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
/*
Rubber Band
An audio time-stretching and pitch-shifting library.
Copyright 2007-2008 Chris Cannam.
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.
*/
#ifndef _RUBBERBAND_STRETCH_CALCULATOR_H_
#define _RUBBERBAND_STRETCH_CALCULATOR_H_
#include <sys/types.h>
#include <vector>
namespace RubberBand
{
class StretchCalculator
{
public:
StretchCalculator(size_t sampleRate, size_t inputIncrement, bool useHardPeaks);
virtual ~StretchCalculator();
/**
* Calculate phase increments for a region of audio, given the
* overall target stretch ratio, input duration in audio samples,
* and the audio curves to use for identifying phase lock points
* (lockAudioCurve) and for allocating stretches to relatively
* less prominent points (stretchAudioCurve).
*/
virtual std::vector<int> calculate(double ratio, size_t inputDuration,
const std::vector<float> &lockAudioCurve,
const std::vector<float> &stretchAudioCurve);
/**
* Calculate the phase increment for a single audio block, given
* the overall target stretch ratio and the block's value on the
* phase-lock audio curve. State is retained between calls in the
* StretchCalculator object; call reset() to reset it. This uses
* a less sophisticated method than the offline calculate().
*
* If increment is non-zero, use it for the input increment for
* this block in preference to m_increment.
*/
virtual int calculateSingle(double ratio, float curveValue,
size_t increment = 0);
void setUseHardPeaks(bool use) { m_useHardPeaks = use; }
void reset();
void setDebugLevel(int level) { m_debugLevel = level; }
struct Peak {
size_t chunk;
bool hard;
};
std::vector<Peak> getLastCalculatedPeaks() const { return m_lastPeaks; }
std::vector<float> smoothDF(const std::vector<float> &df);
protected:
std::vector<Peak> findPeaks(const std::vector<float> &audioCurve);
std::vector<int> distributeRegion(const std::vector<float> ®ionCurve,
size_t outputDuration, float ratio,
bool phaseReset);
void calculateDisplacements(const std::vector<float> &df,
float &maxDf,
double &totalDisplacement,
double &maxDisplacement,
float adj) const;
size_t m_sampleRate;
size_t m_blockSize;
size_t m_increment;
float m_prevDf;
double m_divergence;
float m_recovery;
float m_prevRatio;
int m_transientAmnesty; // only in RT mode; handled differently offline
int m_debugLevel;
bool m_useHardPeaks;
std::vector<Peak> m_lastPeaks;
};
}
#endif
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