comparison DrumTimingLoader_OF/chromagramm/ChordDetect.cpp @ 0:82352cfc0b23

Added files from ISMIR groove drum timing work

+/*
+ *  ChordDetect.cpp
+ *  ChordDetect
+ *
+ *  Created by Adam Stark on 28/04/2008.
+ *  Copyright 2008 __MyCompanyName__. All rights reserved.
+ *
+ */
+
+#include "ChordDetect.h"
+#include <iostream>
+#include <math.h>
+using namespace std;
+
+ChordDetect :: ChordDetect()
+{
+	
+	bias = 1.06;
+	
+	makeprofiles();
+		
+}
+
+//--------------------------------------------------------------------------------------
+// destructor
+ChordDetect :: ~ChordDetect()
+{
+										
+}
+
+
+//--------------------------------------------------------------------------------------
+// main function to be called with 8192 sample frame at 11025 Hz
+void ChordDetect :: C_Detect(float c[],float c_low[])
+{
+	for (int i = 0;i < 12;i++)
+	{
+		chroma[i] = c[i];
+		chroma_low[i] = c_low[i];
+	}
+	
+	calculateweightings();
+	
+	classifychromagram();
+		
+	//cout << root << " " << quality << " " << intervals << endl;
+}
+
+//--------------------------------------------------------------------------------------
+// analyse the chromagram and assign it a root note, chord type and any features
+void ChordDetect :: classifychromagram()
+{
+	int i;
+	int j;
+	int fifth;
+	int chordindex;
+	
+	// remove some of the 5th note energy from chromagram
+	for (i = 0;i < 12;i++)
+	{
+		fifth = (i+7) % 12;
+		chroma[fifth] = chroma[fifth] - (0.1*chroma[i]);
+		
+		if (chroma[fifth] < 0)
+		{
+			chroma[fifth] = 0;
+		}
+		
+	}
+	
+	
+	// major chords
+	for (j=0;j < 12;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],bias,3);
+	}
+	
+	// minor chords
+	for (j=12;j < 24;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],bias,3);
+	}
+	
+	// diminished 5th chords
+	for (j=24;j < 36;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],bias,3);
+	}
+	
+	// augmented 5th chords
+	for (j=36;j < 48;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],bias,3);
+		
+		chord[j] = chord[j] / weight_aug[j-36];
+	}
+	
+	// sus2 chords
+	for (j=48;j < 60;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],1,3);
+		
+		chord[j] = chord[j] / weight_sus[j-48];
+	}
+	
+	// sus4 chords
+	for (j=60;j < 72;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],1,3);
+		
+		chord[j] = chord[j] / weight_sus[j-60];
+	}
+	
+	// major 7th chords
+	for (j=72;j < 84;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],1,4);
+	}
+	
+	// minor 7th chords
+	for (j=84;j < 96;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],bias,4);
+	}
+
+	// dominant 7th chords
+	for (j=96;j < 108;j++)
+	{
+		chord[j] = calcchordvalue(chroma,profiles[j],bias,4);
+	}
+	
+	chordindex = minindex(chord,108);
+	
+	// major
+	if (chordindex < 12)
+	{
+		root = chordindex;
+		quality = 1;
+		intervals = 0;
+	}
+	
+	// minor
+	if ((chordindex >= 12) && (chordindex < 24))
+	{
+		root = chordindex-12;
+		quality = 0;
+		intervals = 0;
+	}
+	
+	// diminished 5th
+	if ((chordindex >= 24) && (chordindex < 36))
+	{
+		root = chordindex-24;
+		quality = 4;
+		intervals = 0;
+	}
+	
+	// augmented 5th
+	if ((chordindex >= 36) && (chordindex < 48))
+	{
+		root = chordindex-36;
+		quality = 6;
+		intervals = 0;
+	}
+	
+	// sus2
+	if ((chordindex >= 48) && (chordindex < 60))
+	{
+		root = chordindex-48;
+		quality = 2;
+		intervals = 2;
+	}
+	
+	// sus4
+	if ((chordindex >= 60) && (chordindex < 72))
+	{
+		root = chordindex-60;
+		quality = 2;
+		intervals = 4;
+	}
+	
+	// major 7th
+	if ((chordindex >= 72) && (chordindex < 84))
+	{
+		root = chordindex-72;
+		quality = 1;
+		intervals = 7;
+	}
+	
+	// minor 7th
+	if ((chordindex >= 84) && (chordindex < 96))
+	{
+		root = chordindex-84;
+		quality = 0;
+		intervals = 7;
+	}
+	
+	// dominant 7th
+	if ((chordindex >= 96) && (chordindex < 108))
+	{
+		root = chordindex-96;
+		quality = 2;
+		intervals = 7;
+	}
+}
+
+//--------------------------------------------------------------------------------------
+// calculate weightings to help distinguish between sus2/sus4 and aug chords
+void ChordDetect :: calculateweightings()
+{
+	int i;
+	float maxval = 0;
+	int fifth;
+	int augfifth;
+	
+	maxval = max(chroma_low,12); 
+		
+	// normalise chroma low
+	for (i = 0;i < 12;i++)
+	{
+		chroma_low[i] = chroma_low[i] / maxval;
+	}
+	
+	// make weight for sus chords
+	for (i = 0;i < 12;i++)
+	{
+		fifth = i+7;
+		augfifth = i+8;
+		
+		if (fifth >= 12)
+		{
+			fifth = fifth-12;
+		}
+		
+		if (augfifth >= 12)
+		{
+			augfifth = augfifth-12;
+		}
+		
+		weight_sus[i] = chroma_low[i] + (chroma_low[fifth]/2);
+		weight_aug[i] = chroma_low[i] + (chroma_low[augfifth]/2);
+	}
+	
+	maxval = max(weight_sus,12);
+	// normalise weight_sus
+	for (i = 0;i < 12;i++)
+	{
+		weight_sus[i] = weight_sus[i] / maxval;
+	}
+	
+	maxval = max(weight_aug,12);
+	// normalise weight_aug
+	for (i = 0;i < 12;i++)
+	{
+		weight_aug[i] = weight_aug[i] / maxval;
+	}
+	
+	
+}
+
+
+//--------------------------------------------------------------------------------------
+// return delta value indicating how similar the chroma is to the chord template - lower value = more similar
+float ChordDetect :: calcchordvalue(float c[],float T[],float biasval, float N)
+{
+	float sum = 0;
+	float delta;
+
+	for (int i=0;i < 12;i++)
+	{
+		sum = sum + ((1-T[i])*(pow(c[i],2)));
+	}
+
+	delta = sqrt(sum) / ((12 - N)*biasval);
+	
+	return delta;
+}
+
+
+//--------------------------------------------------------------------------------------
+// returns max value of an array
+float ChordDetect :: max(float array[],int length)
+{
+	float max = 0;
+	
+	for (int i=0;i < length;i++)
+	{
+		if (array[i] > max)
+		{
+			max = array[i];
+		}
+	}
+	
+	return max;
+}
+
+//--------------------------------------------------------------------------------------
+// returns index of minimum value of array
+int ChordDetect :: minindex(float array[],int length)
+{
+	float min = 10000;
+	int minindex = 0;
+	int i;
+	
+	for (i = 0;i < length;i++)
+	{
+		if (array[i] < min)
+		{
+			min = array[i];
+			minindex = i;
+		}
+	}
+	
+	return minindex;
+}
+
+//--------------------------------------------------------------------------------------
+// calculates bit mask chord profiles
+void ChordDetect :: makeprofiles()
+{
+	int i;
+	int t;
+	int j = 0;
+	int root;
+	int third;
+	int fifth;
+	int seventh;
+	
+	float v1 = 1;
+	float v2 = 1;
+	float v3 = 1;
+	
+	// set profiles matrix to all zeros
+	for (j = 0;j < 108;j++)
+	{
+		for (t = 0;t < 12;t++)
+		{
+			profiles[j][t] = 0;
+		}
+	}
+	
+	// reset j to zero to begin creating profiles
+	j = 0;
+	
+	// major chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+4) % 12;
+		fifth = (i+7) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		
+		j++;				
+	}
+
+	// minor chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+3) % 12;
+		fifth = (i+7) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		
+		j++;				
+	}
+
+	// diminished chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+3) % 12;
+		fifth = (i+6) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		
+		j++;				
+	}	
+	
+	// augmented chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+4) % 12;
+		fifth = (i+8) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		
+		j++;				
+	}	
+	
+	// sus2 chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+2) % 12;
+		fifth = (i+7) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		
+		j++;				
+	}
+	
+	// sus4 chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+5) % 12;
+		fifth = (i+7) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		
+		j++;				
+	}		
+	
+	// major 7th chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+4) % 12;
+		fifth = (i+7) % 12;
+		seventh = (i+11) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		profiles[j][seventh] = v3;
+		
+		j++;				
+	}	
+	
+	// minor 7th chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+3) % 12;
+		fifth = (i+7) % 12;
+		seventh = (i+10) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		profiles[j][seventh] = v3;
+		
+		j++;				
+	}
+	
+	// dominant 7th chords
+	for (i = 0;i < 12;i++)
+	{
+		root = i % 12;
+		third = (i+4) % 12;
+		fifth = (i+7) % 12;
+		seventh = (i+10) % 12;
+		
+		profiles[j][root] = v1;
+		profiles[j][third] = v2;
+		profiles[j][fifth] = v3;
+		profiles[j][seventh] = v3;
+		
+		j++;				
+	}
+}