diff NoveltyCurve.cpp @ 5:8d7e336b41e9

Adding NoveltyCurve.*

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/NoveltyCurve.cpp	Tue Aug 05 15:59:15 2014 +0100
@@ -0,0 +1,139 @@
+//
+//  NoveltyCurve.cpp
+//  Tempogram
+//
+//  Created by Carl Bussey on 10/07/2014.
+//  Copyright (c) 2014 Carl Bussey. All rights reserved.
+//
+
+#include <cmath>
+#include <vector>
+#include <iostream>
+#include "FIRFilter.h"
+#include "WindowFunction.h"
+using namespace std;
+#include "NoveltyCurve.h"
+
+NoveltyCurve::NoveltyCurve(float samplingFrequency, int blockSize, int numberOfBlocks, int compressionConstant) :
+    m_samplingFrequency(samplingFrequency),
+    m_blockSize(blockSize),
+    m_numberOfBlocks(numberOfBlocks),
+    m_compressionConstant(compressionConstant),
+    m_numberOfBands(5),
+    m_bandBoundaries(NULL),
+    m_hannLength(65),
+    m_hannWindow(NULL),
+    m_bandSum(NULL)
+{
+    initialise();
+}
+
+NoveltyCurve::~NoveltyCurve(){
+    cleanup();
+}
+
+void
+NoveltyCurve::initialise(){
+    data = vector<float>(m_numberOfBlocks);
+    
+    m_hannWindow = new float[m_hannLength];
+    WindowFunction::hanning(m_hannWindow, m_hannLength, true);
+    
+    m_bandBoundaries = new int[m_numberOfBands+1]; //make index variable
+    
+    m_bandBoundaries[0] = 0;
+    for (int band = 1; band < m_numberOfBands; band++){
+        float lowFreq = 500*pow(2.5, band-1);
+        m_bandBoundaries[band] = m_blockSize*lowFreq/m_samplingFrequency;
+    }
+    m_bandBoundaries[m_numberOfBands] = m_blockSize/2 + 1;
+    
+    m_bandSum = new float * [m_numberOfBands];
+    for (int i = 0; i < m_numberOfBands; i++){
+        m_bandSum[i] = new float[m_numberOfBlocks];
+    }
+}
+
+void
+NoveltyCurve::cleanup(){
+    delete []m_hannWindow;
+    m_hannWindow = NULL;
+    delete []m_bandBoundaries;
+    m_bandBoundaries = NULL;
+    
+    for(int i = 0; i < m_numberOfBands; i++){
+        delete []m_bandSum[i];
+        m_bandSum[i] = NULL;
+    }
+    delete []m_bandSum;
+    m_bandSum = NULL;
+}
+
+float NoveltyCurve::calculateMax(float ** spectrogram){
+    int specLength = (m_blockSize/2 + 1);
+    float max = 0;
+    
+    for (int j = 0; j < m_numberOfBlocks; j++){
+        for (int i = 0; i < specLength; i++){
+            max = max > spectrogram[i][j] ? max : spectrogram[i][j];
+        }
+    }
+    
+    return max;
+}
+
+void NoveltyCurve::subtractLocalAverage(float * noveltyCurve){
+    vector<float> localAverage(m_numberOfBlocks);
+    
+    FIRFilter *filter = new FIRFilter(m_numberOfBlocks, m_hannLength);
+    filter->process(&noveltyCurve[0], m_hannWindow, &localAverage[0]);
+    delete filter;
+    
+    for (int i = 0; i < m_numberOfBlocks; i++){
+        noveltyCurve[i] -= localAverage[i];
+        noveltyCurve[i] = noveltyCurve[i] >= 0 ? noveltyCurve[i] : 0;
+    }
+}
+
+vector<float>
+NoveltyCurve::spectrogramToNoveltyCurve(float ** spectrogram){
+    
+    float normaliseScale = calculateMax(spectrogram);
+    
+    for (int block = 0; block < m_numberOfBlocks; block++){
+        
+        for (int band = 0; band < m_numberOfBands; band++){
+            
+            int specIndex = m_bandBoundaries[band];
+            int bandEnd = m_bandBoundaries[band+1];
+            
+            while(specIndex < bandEnd){
+                
+                spectrogram[specIndex][block] /= normaliseScale; //normalise
+                spectrogram[specIndex][block] = log(1+m_compressionConstant*spectrogram[specIndex][block]);
+                
+                int currentY = spectrogram[specIndex][block];
+                int prevBlock = block-1;
+                int previousY = prevBlock >= 0 ? spectrogram[specIndex][prevBlock] : 0;
+                
+                if(currentY > previousY){
+                    m_bandSum[band][block] += (currentY - previousY);
+                }
+                
+                //cout << specIndex << endl;
+                specIndex++;
+            }
+        }
+        
+        float total = 0;
+        for(int band = 0; band < m_numberOfBands; band++){
+            total += m_bandSum[band][block];
+        }
+        float average = total/m_numberOfBands;
+        data[block] = average;
+    }
+    
+    subtractLocalAverage(&data[0]);
+    
+    return data;
+}
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