forked from dolphin-emu/dolphin
		
	
		
			
				
	
	
		
			1079 lines
		
	
	
		
			34 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			1079 lines
		
	
	
		
			34 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
////////////////////////////////////////////////////////////////////////////////
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/// 
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/// Sampled sound tempo changer/time stretch algorithm. Changes the sound tempo 
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/// while maintaining the original pitch by using a time domain WSOLA-like 
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/// method with several performance-increasing tweaks.
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///
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/// Note : MMX optimized functions reside in a separate, platform-specific 
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/// file, e.g. 'mmx_win.cpp' or 'mmx_gcc.cpp'
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///
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/// Author        : Copyright (c) Olli Parviainen
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/// Author e-mail : oparviai 'at' iki.fi
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/// SoundTouch WWW: http://www.surina.net/soundtouch
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///
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////////////////////////////////////////////////////////////////////////////////
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//
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// Last changed  : $Date: 2015-08-09 00:00:15 +0300 (Sun, 09 Aug 2015) $
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// File revision : $Revision: 1.12 $
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//
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// $Id: TDStretch.cpp 226 2015-08-08 21:00:15Z oparviai $
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//
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////////////////////////////////////////////////////////////////////////////////
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//
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// License :
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//
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//  SoundTouch audio processing library
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//  Copyright (c) Olli Parviainen
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//
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//  This library is free software; you can redistribute it and/or
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//  modify it under the terms of the GNU Lesser General Public
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//  License as published by the Free Software Foundation; either
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//  version 2.1 of the License, or (at your option) any later version.
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//
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//  This library is distributed in the hope that it will be useful,
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//  but WITHOUT ANY WARRANTY; without even the implied warranty of
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//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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//  Lesser General Public License for more details.
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//
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//  You should have received a copy of the GNU Lesser General Public
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//  License along with this library; if not, write to the Free Software
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//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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//
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////////////////////////////////////////////////////////////////////////////////
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#include <string.h>
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#include <limits.h>
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#include <assert.h>
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#include <math.h>
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#include <float.h>
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#include "STTypes.h"
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#include "cpu_detect.h"
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#include "TDStretch.h"
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using namespace soundtouch;
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#define max(x, y) (((x) > (y)) ? (x) : (y))
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/*****************************************************************************
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 *
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 * Constant definitions
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 *
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 *****************************************************************************/
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// Table for the hierarchical mixing position seeking algorithm
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const short _scanOffsets[5][24]={
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    { 124,  186,  248,  310,  372,  434,  496,  558,  620,  682,  744, 806,
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      868,  930,  992, 1054, 1116, 1178, 1240, 1302, 1364, 1426, 1488,   0},
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    {-100,  -75,  -50,  -25,   25,   50,   75,  100,    0,    0,    0,   0,
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        0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,   0},
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    { -20,  -15,  -10,   -5,    5,   10,   15,   20,    0,    0,    0,   0,
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        0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,   0},
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    {  -4,   -3,   -2,   -1,    1,    2,    3,    4,    0,    0,    0,   0,
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        0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,   0},
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    { 121,  114,   97,  114,   98,  105,  108,   32,  104,   99,  117,  111,
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      116,  100,  110,  117,  111,  115,    0,    0,    0,    0,    0,   0}};
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/*****************************************************************************
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 *
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 * Implementation of the class 'TDStretch'
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 *
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 *****************************************************************************/
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TDStretch::TDStretch() : FIFOProcessor(&outputBuffer)
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{
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    bQuickSeek = false;
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    channels = 2;
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    pMidBuffer = NULL;
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    pMidBufferUnaligned = NULL;
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    overlapLength = 0;
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    bAutoSeqSetting = true;
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    bAutoSeekSetting = true;
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    maxnorm = 0;
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    maxnormf = 1e8;
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    skipFract = 0;
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    tempo = 1.0f;
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    setParameters(44100, DEFAULT_SEQUENCE_MS, DEFAULT_SEEKWINDOW_MS, DEFAULT_OVERLAP_MS);
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    setTempo(1.0f);
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    clear();
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}
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TDStretch::~TDStretch()
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{
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    delete[] pMidBufferUnaligned;
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}
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// Sets routine control parameters. These control are certain time constants
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// defining how the sound is stretched to the desired duration.
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//
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// 'sampleRate' = sample rate of the sound
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// 'sequenceMS' = one processing sequence length in milliseconds (default = 82 ms)
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// 'seekwindowMS' = seeking window length for scanning the best overlapping 
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//      position (default = 28 ms)
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// 'overlapMS' = overlapping length (default = 12 ms)
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void TDStretch::setParameters(int aSampleRate, int aSequenceMS, 
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                              int aSeekWindowMS, int aOverlapMS)
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{
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    // accept only positive parameter values - if zero or negative, use old values instead
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    if (aSampleRate > 0)   this->sampleRate = aSampleRate;
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    if (aOverlapMS > 0)    this->overlapMs = aOverlapMS;
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    if (aSequenceMS > 0)
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    {
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        this->sequenceMs = aSequenceMS;
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        bAutoSeqSetting = false;
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    } 
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    else if (aSequenceMS == 0)
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    {
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        // if zero, use automatic setting
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        bAutoSeqSetting = true;
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    }
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    if (aSeekWindowMS > 0) 
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    {
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        this->seekWindowMs = aSeekWindowMS;
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        bAutoSeekSetting = false;
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    } 
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    else if (aSeekWindowMS == 0) 
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    {
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        // if zero, use automatic setting
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        bAutoSeekSetting = true;
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    }
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    calcSeqParameters();
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    calculateOverlapLength(overlapMs);
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    // set tempo to recalculate 'sampleReq'
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    setTempo(tempo);
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}
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/// Get routine control parameters, see setParameters() function.
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/// Any of the parameters to this function can be NULL, in such case corresponding parameter
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/// value isn't returned.
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void TDStretch::getParameters(int *pSampleRate, int *pSequenceMs, int *pSeekWindowMs, int *pOverlapMs) const
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{
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    if (pSampleRate)
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    {
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        *pSampleRate = sampleRate;
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    }
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    if (pSequenceMs)
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    {
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        *pSequenceMs = (bAutoSeqSetting) ? (USE_AUTO_SEQUENCE_LEN) : sequenceMs;
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    }
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    if (pSeekWindowMs)
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    {
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        *pSeekWindowMs = (bAutoSeekSetting) ? (USE_AUTO_SEEKWINDOW_LEN) : seekWindowMs;
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    }
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    if (pOverlapMs)
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    {
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        *pOverlapMs = overlapMs;
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    }
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}
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// Overlaps samples in 'midBuffer' with the samples in 'pInput'
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void TDStretch::overlapMono(SAMPLETYPE *pOutput, const SAMPLETYPE *pInput) const
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{
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    int i;
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    SAMPLETYPE m1, m2;
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    m1 = (SAMPLETYPE)0;
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    m2 = (SAMPLETYPE)overlapLength;
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    for (i = 0; i < overlapLength ; i ++) 
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    {
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        pOutput[i] = (pInput[i] * m1 + pMidBuffer[i] * m2 ) / overlapLength;
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        m1 += 1;
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        m2 -= 1;
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    }
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}
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void TDStretch::clearMidBuffer()
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{
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    memset(pMidBuffer, 0, channels * sizeof(SAMPLETYPE) * overlapLength);
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}
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void TDStretch::clearInput()
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{
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    inputBuffer.clear();
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    clearMidBuffer();
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}
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// Clears the sample buffers
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void TDStretch::clear()
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{
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    outputBuffer.clear();
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    clearInput();
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}
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// Enables/disables the quick position seeking algorithm. Zero to disable, nonzero
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// to enable
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void TDStretch::enableQuickSeek(bool enable)
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{
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    bQuickSeek = enable;
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}
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// Returns nonzero if the quick seeking algorithm is enabled.
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bool TDStretch::isQuickSeekEnabled() const
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{
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    return bQuickSeek;
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}
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// Seeks for the optimal overlap-mixing position.
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int TDStretch::seekBestOverlapPosition(const SAMPLETYPE *refPos)
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{
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    if (bQuickSeek) 
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    {
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        return seekBestOverlapPositionQuick(refPos);
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    }
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    else 
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    {
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        return seekBestOverlapPositionFull(refPos);
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    }
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}
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// Overlaps samples in 'midBuffer' with the samples in 'pInputBuffer' at position
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// of 'ovlPos'.
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inline void TDStretch::overlap(SAMPLETYPE *pOutput, const SAMPLETYPE *pInput, uint ovlPos) const
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{
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#ifndef USE_MULTICH_ALWAYS
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    if (channels == 1)
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    {
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        // mono sound.
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        overlapMono(pOutput, pInput + ovlPos);
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    }
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    else if (channels == 2)
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    {
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        // stereo sound
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        overlapStereo(pOutput, pInput + 2 * ovlPos);
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    } 
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    else 
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#endif // USE_MULTICH_ALWAYS
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    {
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        assert(channels > 0);
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        overlapMulti(pOutput, pInput + channels * ovlPos);
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    }
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}
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// Seeks for the optimal overlap-mixing position. The 'stereo' version of the
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// routine
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//
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// The best position is determined as the position where the two overlapped
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// sample sequences are 'most alike', in terms of the highest cross-correlation
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// value over the overlapping period
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int TDStretch::seekBestOverlapPositionFull(const SAMPLETYPE *refPos) 
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{
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    int bestOffs;
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    double bestCorr;
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    int i;
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    double norm;
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    bestCorr = FLT_MIN;
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    bestOffs = 0;
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    // Scans for the best correlation value by testing each possible position
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    // over the permitted range.
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    bestCorr = calcCrossCorr(refPos, pMidBuffer, norm);
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    #pragma omp parallel for
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    for (i = 1; i < seekLength; i ++) 
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    {
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        double corr;
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        // Calculates correlation value for the mixing position corresponding to 'i'
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#ifdef _OPENMP
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        // in parallel OpenMP mode, can't use norm accumulator version as parallel executor won't
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        // iterate the loop in sequential order
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        corr = calcCrossCorr(refPos + channels * i, pMidBuffer, norm);
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#else
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        // In non-parallel version call "calcCrossCorrAccumulate" that is otherwise same
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        // as "calcCrossCorr", but saves time by reusing & updating previously stored 
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        // "norm" value
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        corr = calcCrossCorrAccumulate(refPos + channels * i, pMidBuffer, norm);
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#endif
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        // heuristic rule to slightly favour values close to mid of the range
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        double tmp = (double)(2 * i - seekLength) / (double)seekLength;
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        corr = ((corr + 0.1) * (1.0 - 0.25 * tmp * tmp));
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        // Checks for the highest correlation value
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        if (corr > bestCorr) 
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        {
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            // For optimal performance, enter critical section only in case that best value found.
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            // in such case repeat 'if' condition as it's possible that parallel execution may have
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            // updated the bestCorr value in the mean time
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            #pragma omp critical
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            if (corr > bestCorr)
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            {
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                bestCorr = corr;
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                bestOffs = i;
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            }
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        }
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    }
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#ifdef SOUNDTOUCH_INTEGER_SAMPLES
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    adaptNormalizer();
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#endif
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    // clear cross correlation routine state if necessary (is so e.g. in MMX routines).
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    clearCrossCorrState();
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    return bestOffs;
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}
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// Quick seek algorithm for improved runtime-performance: First roughly scans through the 
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// correlation area, and then scan surroundings of two best preliminary correlation candidates
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// with improved precision
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//
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// Based on testing:
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// - This algorithm gives on average 99% as good match as the full algorith
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// - this quick seek algorithm finds the best match on ~90% of cases
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// - on those 10% of cases when this algorithm doesn't find best match, 
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//   it still finds on average ~90% match vs. the best possible match
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int TDStretch::seekBestOverlapPositionQuick(const SAMPLETYPE *refPos)
 | 
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{
 | 
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#define _MIN(a, b)   (((a) < (b)) ? (a) : (b))
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#define SCANSTEP    16
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#define SCANWIND    8
 | 
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 | 
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    int bestOffs;
 | 
						|
    int i;
 | 
						|
    int bestOffs2;
 | 
						|
    float bestCorr, corr;
 | 
						|
    float bestCorr2;
 | 
						|
    double norm;
 | 
						|
 | 
						|
    // note: 'float' types used in this function in case that the platform would need to use software-fp
 | 
						|
 | 
						|
    bestCorr = FLT_MIN;
 | 
						|
    bestOffs = SCANWIND;
 | 
						|
    bestCorr2 = FLT_MIN;
 | 
						|
    bestOffs2 = 0;
 | 
						|
 | 
						|
    int best = 0;
 | 
						|
 | 
						|
    // Scans for the best correlation value by testing each possible position
 | 
						|
    // over the permitted range. Look for two best matches on the first pass to
 | 
						|
    // increase possibility of ideal match.
 | 
						|
    //
 | 
						|
    // Begin from "SCANSTEP" instead of SCANWIND to make the calculation
 | 
						|
    // catch the 'middlepoint' of seekLength vector as that's the a-priori 
 | 
						|
    // expected best match position
 | 
						|
    //
 | 
						|
    // Roughly:
 | 
						|
    // - 15% of cases find best result directly on the first round,
 | 
						|
    // - 75% cases find better match on 2nd round around the best match from 1st round
 | 
						|
    // - 10% cases find better match on 2nd round around the 2nd-best-match from 1st round
 | 
						|
    for (i = SCANSTEP; i < seekLength - SCANWIND - 1; i += SCANSTEP)
 | 
						|
    {
 | 
						|
        // Calculates correlation value for the mixing position corresponding
 | 
						|
        // to 'i'
 | 
						|
        corr = (float)calcCrossCorr(refPos + channels*i, pMidBuffer, norm);
 | 
						|
        // heuristic rule to slightly favour values close to mid of the seek range
 | 
						|
        float tmp = (float)(2 * i - seekLength - 1) / (float)seekLength;
 | 
						|
        corr = ((corr + 0.1f) * (1.0f - 0.25f * tmp * tmp));
 | 
						|
 | 
						|
        // Checks for the highest correlation value
 | 
						|
        if (corr > bestCorr)
 | 
						|
        {
 | 
						|
            // found new best match. keep the previous best as 2nd best match
 | 
						|
            bestCorr2 = bestCorr;
 | 
						|
            bestOffs2 = bestOffs;
 | 
						|
            bestCorr = corr;
 | 
						|
            bestOffs = i;
 | 
						|
        }
 | 
						|
        else if (corr > bestCorr2)
 | 
						|
        {
 | 
						|
            // not new best, but still new 2nd best match
 | 
						|
            bestCorr2 = corr;
 | 
						|
            bestOffs2 = i;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    // Scans surroundings of the found best match with small stepping
 | 
						|
    int end = _MIN(bestOffs + SCANWIND + 1, seekLength);
 | 
						|
    for (i = bestOffs - SCANWIND; i < end; i++)
 | 
						|
    {
 | 
						|
        if (i == bestOffs) continue;    // this offset already calculated, thus skip
 | 
						|
 | 
						|
        // Calculates correlation value for the mixing position corresponding
 | 
						|
        // to 'i'
 | 
						|
        corr = (float)calcCrossCorr(refPos + channels*i, pMidBuffer, norm);
 | 
						|
        // heuristic rule to slightly favour values close to mid of the range
 | 
						|
        float tmp = (float)(2 * i - seekLength - 1) / (float)seekLength;
 | 
						|
        corr = ((corr + 0.1f) * (1.0f - 0.25f * tmp * tmp));
 | 
						|
 | 
						|
        // Checks for the highest correlation value
 | 
						|
        if (corr > bestCorr)
 | 
						|
        {
 | 
						|
            bestCorr = corr;
 | 
						|
            bestOffs = i;
 | 
						|
            best = 1;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    // Scans surroundings of the 2nd best match with small stepping
 | 
						|
    end = _MIN(bestOffs2 + SCANWIND + 1, seekLength);
 | 
						|
    for (i = bestOffs2 - SCANWIND; i < end; i++)
 | 
						|
    {
 | 
						|
        if (i == bestOffs2) continue;    // this offset already calculated, thus skip
 | 
						|
 | 
						|
        // Calculates correlation value for the mixing position corresponding
 | 
						|
        // to 'i'
 | 
						|
        corr = (float)calcCrossCorr(refPos + channels*i, pMidBuffer, norm);
 | 
						|
        // heuristic rule to slightly favour values close to mid of the range
 | 
						|
        float tmp = (float)(2 * i - seekLength - 1) / (float)seekLength;
 | 
						|
        corr = ((corr + 0.1f) * (1.0f - 0.25f * tmp * tmp));
 | 
						|
 | 
						|
        // Checks for the highest correlation value
 | 
						|
        if (corr > bestCorr)
 | 
						|
        {
 | 
						|
            bestCorr = corr;
 | 
						|
            bestOffs = i;
 | 
						|
            best = 2;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    // clear cross correlation routine state if necessary (is so e.g. in MMX routines).
 | 
						|
    clearCrossCorrState();
 | 
						|
 | 
						|
#ifdef SOUNDTOUCH_INTEGER_SAMPLES
 | 
						|
    adaptNormalizer();
 | 
						|
#endif
 | 
						|
 | 
						|
    return bestOffs;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
 | 
						|
 | 
						|
/// For integer algorithm: adapt normalization factor divider with music so that 
 | 
						|
/// it'll not be pessimistically restrictive that can degrade quality on quieter sections
 | 
						|
/// yet won't cause integer overflows either
 | 
						|
void TDStretch::adaptNormalizer()
 | 
						|
{
 | 
						|
    // Do not adapt normalizer over too silent sequences to avoid averaging filter depleting to
 | 
						|
    // too low values during pauses in music
 | 
						|
    if ((maxnorm > 1000) || (maxnormf > 40000000))
 | 
						|
    { 
 | 
						|
        //norm averaging filter
 | 
						|
        maxnormf = 0.9f * maxnormf + 0.1f * (float)maxnorm;
 | 
						|
 | 
						|
        if ((maxnorm > 800000000) && (overlapDividerBitsNorm < 16))
 | 
						|
        {
 | 
						|
            // large values, so increase divider
 | 
						|
            overlapDividerBitsNorm++;
 | 
						|
            if (maxnorm > 1600000000) overlapDividerBitsNorm++; // extra large value => extra increase
 | 
						|
        }
 | 
						|
        else if ((maxnormf < 1000000) && (overlapDividerBitsNorm > 0))
 | 
						|
        {
 | 
						|
            // extra small values, decrease divider
 | 
						|
            overlapDividerBitsNorm--;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    maxnorm = 0;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// clear cross correlation routine state if necessary 
 | 
						|
void TDStretch::clearCrossCorrState()
 | 
						|
{
 | 
						|
    // default implementation is empty.
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Calculates processing sequence length according to tempo setting
 | 
						|
void TDStretch::calcSeqParameters()
 | 
						|
{
 | 
						|
    // Adjust tempo param according to tempo, so that variating processing sequence length is used
 | 
						|
    // at varius tempo settings, between the given low...top limits
 | 
						|
    #define AUTOSEQ_TEMPO_LOW   0.5     // auto setting low tempo range (-50%)
 | 
						|
    #define AUTOSEQ_TEMPO_TOP   2.0     // auto setting top tempo range (+100%)
 | 
						|
 | 
						|
    // sequence-ms setting values at above low & top tempo
 | 
						|
    #define AUTOSEQ_AT_MIN      125.0
 | 
						|
    #define AUTOSEQ_AT_MAX      50.0
 | 
						|
    #define AUTOSEQ_K           ((AUTOSEQ_AT_MAX - AUTOSEQ_AT_MIN) / (AUTOSEQ_TEMPO_TOP - AUTOSEQ_TEMPO_LOW))
 | 
						|
    #define AUTOSEQ_C           (AUTOSEQ_AT_MIN - (AUTOSEQ_K) * (AUTOSEQ_TEMPO_LOW))
 | 
						|
 | 
						|
    // seek-window-ms setting values at above low & top tempoq
 | 
						|
    #define AUTOSEEK_AT_MIN     25.0
 | 
						|
    #define AUTOSEEK_AT_MAX     15.0
 | 
						|
    #define AUTOSEEK_K          ((AUTOSEEK_AT_MAX - AUTOSEEK_AT_MIN) / (AUTOSEQ_TEMPO_TOP - AUTOSEQ_TEMPO_LOW))
 | 
						|
    #define AUTOSEEK_C          (AUTOSEEK_AT_MIN - (AUTOSEEK_K) * (AUTOSEQ_TEMPO_LOW))
 | 
						|
 | 
						|
    #define CHECK_LIMITS(x, mi, ma) (((x) < (mi)) ? (mi) : (((x) > (ma)) ? (ma) : (x)))
 | 
						|
 | 
						|
    double seq, seek;
 | 
						|
    
 | 
						|
    if (bAutoSeqSetting)
 | 
						|
    {
 | 
						|
        seq = AUTOSEQ_C + AUTOSEQ_K * tempo;
 | 
						|
        seq = CHECK_LIMITS(seq, AUTOSEQ_AT_MAX, AUTOSEQ_AT_MIN);
 | 
						|
        sequenceMs = (int)(seq + 0.5);
 | 
						|
    }
 | 
						|
 | 
						|
    if (bAutoSeekSetting)
 | 
						|
    {
 | 
						|
        seek = AUTOSEEK_C + AUTOSEEK_K * tempo;
 | 
						|
        seek = CHECK_LIMITS(seek, AUTOSEEK_AT_MAX, AUTOSEEK_AT_MIN);
 | 
						|
        seekWindowMs = (int)(seek + 0.5);
 | 
						|
    }
 | 
						|
 | 
						|
    // Update seek window lengths
 | 
						|
    seekWindowLength = (sampleRate * sequenceMs) / 1000;
 | 
						|
    if (seekWindowLength < 2 * overlapLength) 
 | 
						|
    {
 | 
						|
        seekWindowLength = 2 * overlapLength;
 | 
						|
    }
 | 
						|
    seekLength = (sampleRate * seekWindowMs) / 1000;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
 | 
						|
// Sets new target tempo. Normal tempo = 'SCALE', smaller values represent slower 
 | 
						|
// tempo, larger faster tempo.
 | 
						|
void TDStretch::setTempo(double newTempo)
 | 
						|
{
 | 
						|
    int intskip;
 | 
						|
 | 
						|
    tempo = newTempo;
 | 
						|
 | 
						|
    // Calculate new sequence duration
 | 
						|
    calcSeqParameters();
 | 
						|
 | 
						|
    // Calculate ideal skip length (according to tempo value) 
 | 
						|
    nominalSkip = tempo * (seekWindowLength - overlapLength);
 | 
						|
    intskip = (int)(nominalSkip + 0.5);
 | 
						|
 | 
						|
    // Calculate how many samples are needed in the 'inputBuffer' to 
 | 
						|
    // process another batch of samples
 | 
						|
    //sampleReq = max(intskip + overlapLength, seekWindowLength) + seekLength / 2;
 | 
						|
    sampleReq = max(intskip + overlapLength, seekWindowLength) + seekLength;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
 | 
						|
// Sets the number of channels, 1 = mono, 2 = stereo
 | 
						|
void TDStretch::setChannels(int numChannels)
 | 
						|
{
 | 
						|
    assert(numChannels > 0);
 | 
						|
    if (channels == numChannels) return;
 | 
						|
//    assert(numChannels == 1 || numChannels == 2);
 | 
						|
 | 
						|
    channels = numChannels;
 | 
						|
    inputBuffer.setChannels(channels);
 | 
						|
    outputBuffer.setChannels(channels);
 | 
						|
 | 
						|
    // re-init overlap/buffer
 | 
						|
    overlapLength=0;
 | 
						|
    setParameters(sampleRate);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
// nominal tempo, no need for processing, just pass the samples through
 | 
						|
// to outputBuffer
 | 
						|
/*
 | 
						|
void TDStretch::processNominalTempo()
 | 
						|
{
 | 
						|
    assert(tempo == 1.0f);
 | 
						|
 | 
						|
    if (bMidBufferDirty) 
 | 
						|
    {
 | 
						|
        // If there are samples in pMidBuffer waiting for overlapping,
 | 
						|
        // do a single sliding overlapping with them in order to prevent a 
 | 
						|
        // clicking distortion in the output sound
 | 
						|
        if (inputBuffer.numSamples() < overlapLength) 
 | 
						|
        {
 | 
						|
            // wait until we've got overlapLength input samples
 | 
						|
            return;
 | 
						|
        }
 | 
						|
        // Mix the samples in the beginning of 'inputBuffer' with the 
 | 
						|
        // samples in 'midBuffer' using sliding overlapping 
 | 
						|
        overlap(outputBuffer.ptrEnd(overlapLength), inputBuffer.ptrBegin(), 0);
 | 
						|
        outputBuffer.putSamples(overlapLength);
 | 
						|
        inputBuffer.receiveSamples(overlapLength);
 | 
						|
        clearMidBuffer();
 | 
						|
        // now we've caught the nominal sample flow and may switch to
 | 
						|
        // bypass mode
 | 
						|
    }
 | 
						|
 | 
						|
    // Simply bypass samples from input to output
 | 
						|
    outputBuffer.moveSamples(inputBuffer);
 | 
						|
}
 | 
						|
*/
 | 
						|
 | 
						|
 | 
						|
// Processes as many processing frames of the samples 'inputBuffer', store
 | 
						|
// the result into 'outputBuffer'
 | 
						|
void TDStretch::processSamples()
 | 
						|
{
 | 
						|
    int ovlSkip, offset;
 | 
						|
    int temp;
 | 
						|
 | 
						|
    /* Removed this small optimization - can introduce a click to sound when tempo setting
 | 
						|
       crosses the nominal value
 | 
						|
    if (tempo == 1.0f) 
 | 
						|
    {
 | 
						|
        // tempo not changed from the original, so bypass the processing
 | 
						|
        processNominalTempo();
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    */
 | 
						|
 | 
						|
    // Process samples as long as there are enough samples in 'inputBuffer'
 | 
						|
    // to form a processing frame.
 | 
						|
    while ((int)inputBuffer.numSamples() >= sampleReq) 
 | 
						|
    {
 | 
						|
        // If tempo differs from the normal ('SCALE'), scan for the best overlapping
 | 
						|
        // position
 | 
						|
        offset = seekBestOverlapPosition(inputBuffer.ptrBegin());
 | 
						|
 | 
						|
        // Mix the samples in the 'inputBuffer' at position of 'offset' with the 
 | 
						|
        // samples in 'midBuffer' using sliding overlapping
 | 
						|
        // ... first partially overlap with the end of the previous sequence
 | 
						|
        // (that's in 'midBuffer')
 | 
						|
        overlap(outputBuffer.ptrEnd((uint)overlapLength), inputBuffer.ptrBegin(), (uint)offset);
 | 
						|
        outputBuffer.putSamples((uint)overlapLength);
 | 
						|
 | 
						|
        // ... then copy sequence samples from 'inputBuffer' to output:
 | 
						|
 | 
						|
        // length of sequence
 | 
						|
        temp = (seekWindowLength - 2 * overlapLength);
 | 
						|
 | 
						|
        // crosscheck that we don't have buffer overflow...
 | 
						|
        if ((int)inputBuffer.numSamples() < (offset + temp + overlapLength * 2))
 | 
						|
        {
 | 
						|
            continue;    // just in case, shouldn't really happen
 | 
						|
        }
 | 
						|
 | 
						|
        outputBuffer.putSamples(inputBuffer.ptrBegin() + channels * (offset + overlapLength), (uint)temp);
 | 
						|
 | 
						|
        // Copies the end of the current sequence from 'inputBuffer' to 
 | 
						|
        // 'midBuffer' for being mixed with the beginning of the next 
 | 
						|
        // processing sequence and so on
 | 
						|
        assert((offset + temp + overlapLength * 2) <= (int)inputBuffer.numSamples());
 | 
						|
        memcpy(pMidBuffer, inputBuffer.ptrBegin() + channels * (offset + temp + overlapLength), 
 | 
						|
            channels * sizeof(SAMPLETYPE) * overlapLength);
 | 
						|
 | 
						|
        // Remove the processed samples from the input buffer. Update
 | 
						|
        // the difference between integer & nominal skip step to 'skipFract'
 | 
						|
        // in order to prevent the error from accumulating over time.
 | 
						|
        skipFract += nominalSkip;   // real skip size
 | 
						|
        ovlSkip = (int)skipFract;   // rounded to integer skip
 | 
						|
        skipFract -= ovlSkip;       // maintain the fraction part, i.e. real vs. integer skip
 | 
						|
        inputBuffer.receiveSamples((uint)ovlSkip);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
// Adds 'numsamples' pcs of samples from the 'samples' memory position into
 | 
						|
// the input of the object.
 | 
						|
void TDStretch::putSamples(const SAMPLETYPE *samples, uint nSamples)
 | 
						|
{
 | 
						|
    // Add the samples into the input buffer
 | 
						|
    inputBuffer.putSamples(samples, nSamples);
 | 
						|
    // Process the samples in input buffer
 | 
						|
    processSamples();
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
 | 
						|
/// Set new overlap length parameter & reallocate RefMidBuffer if necessary.
 | 
						|
void TDStretch::acceptNewOverlapLength(int newOverlapLength)
 | 
						|
{
 | 
						|
    int prevOvl;
 | 
						|
 | 
						|
    assert(newOverlapLength >= 0);
 | 
						|
    prevOvl = overlapLength;
 | 
						|
    overlapLength = newOverlapLength;
 | 
						|
 | 
						|
    if (overlapLength > prevOvl)
 | 
						|
    {
 | 
						|
        delete[] pMidBufferUnaligned;
 | 
						|
 | 
						|
        pMidBufferUnaligned = new SAMPLETYPE[overlapLength * channels + 16 / sizeof(SAMPLETYPE)];
 | 
						|
        // ensure that 'pMidBuffer' is aligned to 16 byte boundary for efficiency
 | 
						|
        pMidBuffer = (SAMPLETYPE *)SOUNDTOUCH_ALIGN_POINTER_16(pMidBufferUnaligned);
 | 
						|
 | 
						|
        clearMidBuffer();
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
// Operator 'new' is overloaded so that it automatically creates a suitable instance 
 | 
						|
// depending on if we've a MMX/SSE/etc-capable CPU available or not.
 | 
						|
void * TDStretch::operator new(size_t s)
 | 
						|
{
 | 
						|
    // Notice! don't use "new TDStretch" directly, use "newInstance" to create a new instance instead!
 | 
						|
    ST_THROW_RT_ERROR("Error in TDStretch::new: Don't use 'new TDStretch' directly, use 'newInstance' member instead!");
 | 
						|
    return newInstance();
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
TDStretch * TDStretch::newInstance()
 | 
						|
{
 | 
						|
    uint uExtensions;
 | 
						|
 | 
						|
    uExtensions = detectCPUextensions();
 | 
						|
 | 
						|
    // Check if MMX/SSE instruction set extensions supported by CPU
 | 
						|
 | 
						|
#ifdef SOUNDTOUCH_ALLOW_MMX
 | 
						|
    // MMX routines available only with integer sample types
 | 
						|
    if (uExtensions & SUPPORT_MMX)
 | 
						|
    {
 | 
						|
        return ::new TDStretchMMX;
 | 
						|
    }
 | 
						|
    else
 | 
						|
#endif // SOUNDTOUCH_ALLOW_MMX
 | 
						|
 | 
						|
 | 
						|
#ifdef SOUNDTOUCH_ALLOW_SSE
 | 
						|
    if (uExtensions & SUPPORT_SSE)
 | 
						|
    {
 | 
						|
        // SSE support
 | 
						|
        return ::new TDStretchSSE;
 | 
						|
    }
 | 
						|
    else
 | 
						|
#endif // SOUNDTOUCH_ALLOW_SSE
 | 
						|
 | 
						|
    {
 | 
						|
        // ISA optimizations not supported, use plain C version
 | 
						|
        return ::new TDStretch;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
//////////////////////////////////////////////////////////////////////////////
 | 
						|
//
 | 
						|
// Integer arithmetics specific algorithm implementations.
 | 
						|
//
 | 
						|
//////////////////////////////////////////////////////////////////////////////
 | 
						|
 | 
						|
#ifdef SOUNDTOUCH_INTEGER_SAMPLES
 | 
						|
 | 
						|
// Overlaps samples in 'midBuffer' with the samples in 'input'. The 'Stereo' 
 | 
						|
// version of the routine.
 | 
						|
void TDStretch::overlapStereo(short *poutput, const short *input) const
 | 
						|
{
 | 
						|
    int i;
 | 
						|
    short temp;
 | 
						|
    int cnt2;
 | 
						|
 | 
						|
    for (i = 0; i < overlapLength ; i ++) 
 | 
						|
    {
 | 
						|
        temp = (short)(overlapLength - i);
 | 
						|
        cnt2 = 2 * i;
 | 
						|
        poutput[cnt2] = (input[cnt2] * i + pMidBuffer[cnt2] * temp )  / overlapLength;
 | 
						|
        poutput[cnt2 + 1] = (input[cnt2 + 1] * i + pMidBuffer[cnt2 + 1] * temp ) / overlapLength;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
// Overlaps samples in 'midBuffer' with the samples in 'input'. The 'Multi'
 | 
						|
// version of the routine.
 | 
						|
void TDStretch::overlapMulti(SAMPLETYPE *poutput, const SAMPLETYPE *input) const
 | 
						|
{
 | 
						|
    SAMPLETYPE m1=(SAMPLETYPE)0;
 | 
						|
    SAMPLETYPE m2;
 | 
						|
    int i=0;
 | 
						|
 | 
						|
    for (m2 = (SAMPLETYPE)overlapLength; m2; m2 --)
 | 
						|
    {
 | 
						|
        for (int c = 0; c < channels; c ++)
 | 
						|
        {
 | 
						|
            poutput[i] = (input[i] * m1 + pMidBuffer[i] * m2)  / overlapLength;
 | 
						|
            i++;
 | 
						|
        }
 | 
						|
 | 
						|
        m1++;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
// Calculates the x having the closest 2^x value for the given value
 | 
						|
static int _getClosest2Power(double value)
 | 
						|
{
 | 
						|
    return (int)(log(value) / log(2.0) + 0.5);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Calculates overlap period length in samples.
 | 
						|
/// Integer version rounds overlap length to closest power of 2
 | 
						|
/// for a divide scaling operation.
 | 
						|
void TDStretch::calculateOverlapLength(int aoverlapMs)
 | 
						|
{
 | 
						|
    int newOvl;
 | 
						|
 | 
						|
    assert(aoverlapMs >= 0);
 | 
						|
 | 
						|
    // calculate overlap length so that it's power of 2 - thus it's easy to do
 | 
						|
    // integer division by right-shifting. Term "-1" at end is to account for 
 | 
						|
    // the extra most significatnt bit left unused in result by signed multiplication 
 | 
						|
    overlapDividerBitsPure = _getClosest2Power((sampleRate * aoverlapMs) / 1000.0) - 1;
 | 
						|
    if (overlapDividerBitsPure > 9) overlapDividerBitsPure = 9;
 | 
						|
    if (overlapDividerBitsPure < 3) overlapDividerBitsPure = 3;
 | 
						|
    newOvl = (int)pow(2.0, (int)overlapDividerBitsPure + 1);    // +1 => account for -1 above
 | 
						|
 | 
						|
    acceptNewOverlapLength(newOvl);
 | 
						|
 | 
						|
    overlapDividerBitsNorm = overlapDividerBitsPure;
 | 
						|
 | 
						|
    // calculate sloping divider so that crosscorrelation operation won't 
 | 
						|
    // overflow 32-bit register. Max. sum of the crosscorrelation sum without 
 | 
						|
    // divider would be 2^30*(N^3-N)/3, where N = overlap length
 | 
						|
    slopingDivider = (newOvl * newOvl - 1) / 3;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
double TDStretch::calcCrossCorr(const short *mixingPos, const short *compare, double &norm)
 | 
						|
{
 | 
						|
    long corr;
 | 
						|
    unsigned long lnorm;
 | 
						|
    int i;
 | 
						|
 | 
						|
    corr = lnorm = 0;
 | 
						|
    // Same routine for stereo and mono. For stereo, unroll loop for better
 | 
						|
    // efficiency and gives slightly better resolution against rounding. 
 | 
						|
    // For mono it same routine, just  unrolls loop by factor of 4
 | 
						|
    for (i = 0; i < channels * overlapLength; i += 4) 
 | 
						|
    {
 | 
						|
        corr += (mixingPos[i] * compare[i] + 
 | 
						|
                 mixingPos[i + 1] * compare[i + 1]) >> overlapDividerBitsNorm;  // notice: do intermediate division here to avoid integer overflow
 | 
						|
        corr += (mixingPos[i + 2] * compare[i + 2] + 
 | 
						|
                mixingPos[i + 3] * compare[i + 3]) >> overlapDividerBitsNorm;
 | 
						|
        lnorm += (mixingPos[i] * mixingPos[i] + 
 | 
						|
                mixingPos[i + 1] * mixingPos[i + 1]) >> overlapDividerBitsNorm; // notice: do intermediate division here to avoid integer overflow
 | 
						|
        lnorm += (mixingPos[i + 2] * mixingPos[i + 2] + 
 | 
						|
                mixingPos[i + 3] * mixingPos[i + 3]) >> overlapDividerBitsNorm;
 | 
						|
    }
 | 
						|
 | 
						|
    if (lnorm > maxnorm)
 | 
						|
    {
 | 
						|
        maxnorm = lnorm;
 | 
						|
    }
 | 
						|
    // Normalize result by dividing by sqrt(norm) - this step is easiest 
 | 
						|
    // done using floating point operation
 | 
						|
    norm = (double)lnorm;
 | 
						|
    return (double)corr / sqrt((norm < 1e-9) ? 1.0 : norm);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Update cross-correlation by accumulating "norm" coefficient by previously calculated value
 | 
						|
double TDStretch::calcCrossCorrAccumulate(const short *mixingPos, const short *compare, double &norm)
 | 
						|
{
 | 
						|
    long corr;
 | 
						|
    unsigned long lnorm;
 | 
						|
    int i;
 | 
						|
 | 
						|
    // cancel first normalizer tap from previous round
 | 
						|
    lnorm = 0;
 | 
						|
    for (i = 1; i <= channels; i ++)
 | 
						|
    {
 | 
						|
        lnorm -= (mixingPos[-i] * mixingPos[-i]) >> overlapDividerBitsNorm;
 | 
						|
    }
 | 
						|
 | 
						|
    corr = 0;
 | 
						|
    // Same routine for stereo and mono. For stereo, unroll loop for better
 | 
						|
    // efficiency and gives slightly better resolution against rounding. 
 | 
						|
    // For mono it same routine, just  unrolls loop by factor of 4
 | 
						|
    for (i = 0; i < channels * overlapLength; i += 4) 
 | 
						|
    {
 | 
						|
        corr += (mixingPos[i] * compare[i] + 
 | 
						|
                 mixingPos[i + 1] * compare[i + 1]) >> overlapDividerBitsNorm;  // notice: do intermediate division here to avoid integer overflow
 | 
						|
        corr += (mixingPos[i + 2] * compare[i + 2] + 
 | 
						|
                 mixingPos[i + 3] * compare[i + 3]) >> overlapDividerBitsNorm;
 | 
						|
    }
 | 
						|
 | 
						|
    // update normalizer with last samples of this round
 | 
						|
    for (int j = 0; j < channels; j ++)
 | 
						|
    {
 | 
						|
        i --;
 | 
						|
        lnorm += (mixingPos[i] * mixingPos[i]) >> overlapDividerBitsNorm;
 | 
						|
    }
 | 
						|
 | 
						|
    norm += (double)lnorm;
 | 
						|
    if (norm > maxnorm)
 | 
						|
    {
 | 
						|
        maxnorm = (unsigned long)norm;
 | 
						|
    }
 | 
						|
 | 
						|
    // Normalize result by dividing by sqrt(norm) - this step is easiest 
 | 
						|
    // done using floating point operation
 | 
						|
    return (double)corr / sqrt((norm < 1e-9) ? 1.0 : norm);
 | 
						|
}
 | 
						|
 | 
						|
#endif // SOUNDTOUCH_INTEGER_SAMPLES
 | 
						|
 | 
						|
//////////////////////////////////////////////////////////////////////////////
 | 
						|
//
 | 
						|
// Floating point arithmetics specific algorithm implementations.
 | 
						|
//
 | 
						|
 | 
						|
#ifdef SOUNDTOUCH_FLOAT_SAMPLES
 | 
						|
 | 
						|
// Overlaps samples in 'midBuffer' with the samples in 'pInput'
 | 
						|
void TDStretch::overlapStereo(float *pOutput, const float *pInput) const
 | 
						|
{
 | 
						|
    int i;
 | 
						|
    float fScale;
 | 
						|
    float f1;
 | 
						|
    float f2;
 | 
						|
 | 
						|
    fScale = 1.0f / (float)overlapLength;
 | 
						|
 | 
						|
    f1 = 0;
 | 
						|
    f2 = 1.0f;
 | 
						|
 | 
						|
    for (i = 0; i < 2 * (int)overlapLength ; i += 2) 
 | 
						|
    {
 | 
						|
        pOutput[i + 0] = pInput[i + 0] * f1 + pMidBuffer[i + 0] * f2;
 | 
						|
        pOutput[i + 1] = pInput[i + 1] * f1 + pMidBuffer[i + 1] * f2;
 | 
						|
 | 
						|
        f1 += fScale;
 | 
						|
        f2 -= fScale;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
// Overlaps samples in 'midBuffer' with the samples in 'input'. 
 | 
						|
void TDStretch::overlapMulti(float *pOutput, const float *pInput) const
 | 
						|
{
 | 
						|
    int i;
 | 
						|
    float fScale;
 | 
						|
    float f1;
 | 
						|
    float f2;
 | 
						|
 | 
						|
    fScale = 1.0f / (float)overlapLength;
 | 
						|
 | 
						|
    f1 = 0;
 | 
						|
    f2 = 1.0f;
 | 
						|
 | 
						|
    i=0;
 | 
						|
    for (int i2 = 0; i2 < overlapLength; i2 ++)
 | 
						|
    {
 | 
						|
        // note: Could optimize this slightly by taking into account that always channels > 2
 | 
						|
        for (int c = 0; c < channels; c ++)
 | 
						|
        {
 | 
						|
            pOutput[i] = pInput[i] * f1 + pMidBuffer[i] * f2;
 | 
						|
            i++;
 | 
						|
        }
 | 
						|
        f1 += fScale;
 | 
						|
        f2 -= fScale;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Calculates overlapInMsec period length in samples.
 | 
						|
void TDStretch::calculateOverlapLength(int overlapInMsec)
 | 
						|
{
 | 
						|
    int newOvl;
 | 
						|
 | 
						|
    assert(overlapInMsec >= 0);
 | 
						|
    newOvl = (sampleRate * overlapInMsec) / 1000;
 | 
						|
    if (newOvl < 16) newOvl = 16;
 | 
						|
 | 
						|
    // must be divisible by 8
 | 
						|
    newOvl -= newOvl % 8;
 | 
						|
 | 
						|
    acceptNewOverlapLength(newOvl);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Calculate cross-correlation
 | 
						|
double TDStretch::calcCrossCorr(const float *mixingPos, const float *compare, double &anorm)
 | 
						|
{
 | 
						|
    double corr;
 | 
						|
    double norm;
 | 
						|
    int i;
 | 
						|
 | 
						|
    corr = norm = 0;
 | 
						|
    // Same routine for stereo and mono. For Stereo, unroll by factor of 2.
 | 
						|
    // For mono it's same routine yet unrollsd by factor of 4.
 | 
						|
    for (i = 0; i < channels * overlapLength; i += 4) 
 | 
						|
    {
 | 
						|
        corr += mixingPos[i] * compare[i] +
 | 
						|
                mixingPos[i + 1] * compare[i + 1];
 | 
						|
 | 
						|
        norm += mixingPos[i] * mixingPos[i] + 
 | 
						|
                mixingPos[i + 1] * mixingPos[i + 1];
 | 
						|
 | 
						|
        // unroll the loop for better CPU efficiency:
 | 
						|
        corr += mixingPos[i + 2] * compare[i + 2] +
 | 
						|
                mixingPos[i + 3] * compare[i + 3];
 | 
						|
 | 
						|
        norm += mixingPos[i + 2] * mixingPos[i + 2] +
 | 
						|
                mixingPos[i + 3] * mixingPos[i + 3];
 | 
						|
    }
 | 
						|
 | 
						|
    anorm = norm;
 | 
						|
    return corr / sqrt((norm < 1e-9 ? 1.0 : norm));
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/// Update cross-correlation by accumulating "norm" coefficient by previously calculated value
 | 
						|
double TDStretch::calcCrossCorrAccumulate(const float *mixingPos, const float *compare, double &norm)
 | 
						|
{
 | 
						|
    double corr;
 | 
						|
    int i;
 | 
						|
 | 
						|
    corr = 0;
 | 
						|
 | 
						|
    // cancel first normalizer tap from previous round
 | 
						|
    for (i = 1; i <= channels; i ++)
 | 
						|
    {
 | 
						|
        norm -= mixingPos[-i] * mixingPos[-i];
 | 
						|
    }
 | 
						|
 | 
						|
    // Same routine for stereo and mono. For Stereo, unroll by factor of 2.
 | 
						|
    // For mono it's same routine yet unrollsd by factor of 4.
 | 
						|
    for (i = 0; i < channels * overlapLength; i += 4) 
 | 
						|
    {
 | 
						|
        corr += mixingPos[i] * compare[i] +
 | 
						|
                mixingPos[i + 1] * compare[i + 1] +
 | 
						|
                mixingPos[i + 2] * compare[i + 2] +
 | 
						|
                mixingPos[i + 3] * compare[i + 3];
 | 
						|
    }
 | 
						|
 | 
						|
    // update normalizer with last samples of this round
 | 
						|
    for (int j = 0; j < channels; j ++)
 | 
						|
    {
 | 
						|
        i --;
 | 
						|
        norm += mixingPos[i] * mixingPos[i];
 | 
						|
    }
 | 
						|
 | 
						|
    return corr / sqrt((norm < 1e-9 ? 1.0 : norm));
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
#endif // SOUNDTOUCH_FLOAT_SAMPLES
 |