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Extensive changes to improve NoteTrack display and (some) editing, NoteTrack playback via MIDI, and Midi-to-Audio alignment.

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rbdannenberg
2010-09-18 21:02:36 +00:00
parent f6327602e8
commit a1f0e5ed5b
96 changed files with 5679 additions and 3566 deletions
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99
lib-src/libscorealign/comp_chroma.cpp
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@@ -1,64 +1,15 @@
#include <math.h>
#include <fstream>
#include <algorithm>
#include "allegro.h"
#include "audioreader.h"
#include "scorealign.h"
#include "gen_chroma.h"
#include "comp_chroma.h"
using namespace std;
/* NORM_CHROMA
*
* This function normalizes the chroma for each frame of the
* chrom_energy to mean 0 and std. dev. 1. But if this is a
* "silent frame", set the 13th element to 1.
*/
void norm_chroma( int len, float *chrom_energy ) {
float avg = 0;
float dev = 0;
float sum = 0;
for( int i = 0; i < len; i++ ) {
/* Calculate avg for this frame */
sum = 0;
for ( int j = 0; j < 12; j++ )
sum += AREF2(chrom_energy, i, j);
avg = sum / 12.0;
/* Silence detection: */
float silence = 0.0F;
if (avg < SILENCE_THRESHOLD) { /* assume silent */
silence = 1.0F;
}
AREF2(chrom_energy, i, 12) = silence;
// printf("avg at %g: %g\n", i * 0.25, avg);
/* Normalize this frame to avg. 0 */
for ( int j = 0; j < 12; j++ )
AREF2(chrom_energy, i, j) -= avg;
/* Calculate std. dev. for this frame */
sum = 0;
for ( int j = 0; j < 12; j++ ) {
float x = AREF2(chrom_energy, i, j);
sum += x * x;
}
dev = sqrt( sum / 12.0 );
if (dev == 0.0) dev = 1.0F; /* don't divide by zero */
/* Normalize this frame to std. dev. 1*/
for ( int j = 0; j < 12; j++ )
AREF2(chrom_energy, i, j) /= dev;
}
}
/* Returns the minimum of two values */
double min2( double x, double y ) {
return (x < y ? x : y);
}
#define SILENCE_DISTANCE 16.0
/* GEN_DIST
*
@@ -66,27 +17,23 @@ double min2( double x, double y ) {
* and j in two chroma vectors for use with dynamic time warping of
* the chroma vectors.
*/
float gen_dist( int i, int j, float *chrom_energy1,
float *chrom_energy2 ) {
float sum = 0;
float MAX = 12.0;
if (AREF2(chrom_energy1, i, CHROMA_BIN_COUNT) !=
AREF2(chrom_energy2, j, CHROMA_BIN_COUNT)) {
//printf("gd%g ", SILENCE_DISTANCE); // print result
return SILENCE_DISTANCE;
}
/* Determine the distance between these vectors
chroma1[i] and chroma2[j] to return */
for (int k = 0; k < 12; k++) {
float x = AREF2(chrom_energy1, i, k);
float y = AREF2(chrom_energy2, j, k);
float diff = x - y;
sum += diff*diff ;
}
sum = min2( sqrt( sum ), MAX );
//printf("gd%g ", sum); // print the result
return sum;
float Scorealign::gen_dist(int i, int j)
{
const float MAX = 12.0;
assert(i < file0_frames);
assert(j < file1_frames);
float *cv0 = AREF1(chrom_energy0, i);
float *cv1 = AREF1(chrom_energy1, j);
if (cv0[CHROMA_BIN_COUNT] != cv1[CHROMA_BIN_COUNT]) {
// silent frames are a (large) constant distance from non-silent frames
return SILENCE_DISTANCE;
}
/* calculate the Euclidean distance between these vectors */
float sum = 0;
for (int k = 0; k < CHROMA_BIN_COUNT; k++) {
float diff = cv0[k] - cv1[k];
sum += diff * diff ;
}
// place a ceiling (MAX) on distance
return min(sqrt(sum), MAX);
}