Chris@43: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@43: 
Chris@43: /*
Chris@43:    Vamp Tempogram Plugin
Chris@43:    Carl Bussey, Centre for Digital Music, Queen Mary University of London
Chris@43:    Copyright 2014 Queen Mary University of London.
Chris@43:     
Chris@43:    This program is free software; you can redistribute it and/or
Chris@43:    modify it under the terms of the GNU General Public License as
Chris@43:    published by the Free Software Foundation; either version 2 of the
Chris@43:    License, or (at your option) any later version.  See the file
Chris@43:    COPYING included with this distribution for more information.
Chris@43: */
c@25: 
c@25: #include "AutocorrelationProcessor.h"
c@25: using namespace std;
c@28: #include <iostream>
c@25: 
Chris@44: AutocorrelationProcessor::AutocorrelationProcessor(int windowLength, int hopSize) :
c@25:     m_windowLength(windowLength),
c@28:     m_hopSize(hopSize)
c@25: {
c@28: 
c@26: }
c@26: 
c@29: AutocorrelationProcessor::~AutocorrelationProcessor()
c@29: {
c@28: 
c@25: }
c@25: 
Chris@44: AutoCorrelation AutocorrelationProcessor::process(float * input, int inputLength) const
c@25: {
c@25:     int readBlockPointerIndex = 0;
c@25:     AutoCorrelation autocorrelation;
c@25:     
Chris@44:     while(readBlockPointerIndex <= inputLength) {
c@25:         
c@28:         vector<float> autocorrelationBlock;
c@28:         
Chris@44:         for (int lag = 0; lag < m_windowLength; lag++){
c@28:             float sum = 0;
c@28:             int readPointer = readBlockPointerIndex - m_windowLength/2;
c@26:             
c@28:             for (int n = 0; n < (int)m_windowLength; n++){
Chris@44:                 if (readPointer+lag >= inputLength) break;
Chris@44:                 else if (readPointer >= 0) {
Chris@44: 		    sum += input[readPointer]*input[readPointer+lag];
Chris@44: 		}
c@28:                 readPointer++;
c@28:             }
c@28:             autocorrelationBlock.push_back(sum/(2*m_windowLength + 1 - lag));
c@26:         }
c@26:         
c@28:         autocorrelation.push_back(autocorrelationBlock);
c@25:         readBlockPointerIndex += m_hopSize;
c@25:     }
c@25:     
c@25:     return autocorrelation;
c@25: }