medvedych/SailTuner
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

ZeroCross: algo fix and energy deviation implement

Browse source 
Don't use energy deviation for the moment ; only the time deviation with the
fix makes things better and to be tested.
This commit is contained in:
Louis-Joseph Fournier 2015-12-29 11:05:51 +01:00
parent d322ec1c5e
commit 73318f3551
2 changed files with 61 additions and 33 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

78
src/audio/ZeroCross.cpp
View file

@ -5,40 +5,52 @@
#include <math.h>
using namespace std;
using namespace patterns;
/// Maximum rest of division to be a multiple of
#define EPS_DIVISOR 0.1
/// Consider it is a correct pattern to avoid multiples of
#define CORRECT_DEVIATION 1
#define CORRECT_TIME_DEVIATION 1
/// max factor of deviation to consider multiple to be dropped
#define MAX_TIME_DEVIATION_FACTOR_MULTIPLE 2
//#define CORRECT_ENERGY_DEVIATION 1
// local functions
/**
* Return average and standart deviation of pattern approx. interval in values
*/
pair<double,double> IsPattern(const vector<double> &values, double interval)
PatternMatch IsPattern(const vector<Pattern> &values, double interval)
{
double sum = 0, deviation = 0, current = 0;
double current = 0;
int nb = 0;
double diff = interval;
double sum_energy = 0, first_energy = -1;
PatternMatch match;
for (double v : values) {
if (fabs(diff - v) < fabs(diff)) {
current += v;
for (const Pattern &v : values) {
if (fabs(diff - v.time) < fabs(diff)) {
current += v.time;
sum_energy += v.energy;
diff = interval - current;
}
else {
sum += current;
deviation += diff * diff;
current = 0;
diff = interval;
if (first_energy == -1) first_energy = sum_energy;
match.time += current;
match.time_deviation += diff * diff;
match.energy_deviation += pow(first_energy - sum_energy, 2);
current = v.time;
sum_energy = v.energy;
diff = interval - current;
nb++;
}
}
if (nb < 2) return pair<double,double>(0,0);
sum /= nb;
deviation = sqrt(deviation) / nb;
return pair<double,double>(sum, deviation);
if (nb < 2) return PatternMatch(); // empty pattern
match.time /= nb; // time is average
match.time_deviation = sqrt(match.time_deviation) / nb;
match.energy_deviation = sqrt(match.energy_deviation) / match.time;
return match;
}
/**
@ -47,21 +59,21 @@ pair<double,double> IsPattern(const vector<double> &values, double interval)
*
* @return best interval pattern, standart deviation for best pattern
*/
pair<double,double> FindPattern(const vector<double> &values, double pattern_min, double pattern_max)
PatternMatch FindPattern(const vector<Pattern> &values, double pattern_min, double pattern_max)
{
auto best = pair<double,double>(0,0);
PatternMatch res, best;
double interval = 0;
for (double v : values) {
interval += v;
for (const Pattern &v : values) {
interval += v.time;
if (interval < pattern_min) continue;
if (interval > pattern_max) break;
auto res = IsPattern(values, interval);
// cout << " " << res.first << " " << res.second << endl;
if (res.first && (res.second < best.second || best.first == 0)) {
if (best.first && best.second < CORRECT_DEVIATION) {
double div = res.first / best.first;
res = IsPattern(values, interval);
// cout << " " << res.time << " " << 16000/res.time << " " << res.time_deviation << " " << res.energy_deviation << endl;
if (res.time && (res.time_deviation < best.time_deviation || best.time == 0)) {
if (best.time && best.time_deviation < CORRECT_TIME_DEVIATION && best.time_deviation / res.time_deviation < MAX_TIME_DEVIATION_FACTOR_MULTIPLE) {
double div = res.time / best.time;
// it is a multiple of previous
if (fabs(div - round(div)) < EPS_DIVISOR) continue;
// cout << "... " << div - floor(div) << endl;
@ -70,7 +82,7 @@ pair<double,double> FindPattern(const vector<double> &values, double pattern_min
}
}
//cerr << " -> " << best.first << " " << best.second << endl;
if (best.second > CORRECT_DEVIATION) return pair<double,double>(0,0);
if (best.time_deviation > CORRECT_TIME_DEVIATION) return PatternMatch(); // empty pattern
return best;
}
@ -88,7 +100,7 @@ template<typename A> ZeroCross<A>::ZeroCross(const Config &config)
template<typename sample_t> void ZeroCross<sample_t>::Clear()
{
nb_frame_current = -1;
pattern_current.time = -1;
nb_frame_analysed = 0;
freq = 0;
last_zero = false;
@ -100,18 +112,22 @@ template<typename sample_t> void ZeroCross<sample_t>::ComputeFrame(sample_t x)
double delta;
// count frame only if ever crossed
if (nb_frame_current != -1) nb_frame_current++;
if (pattern_current.time != -1) {
pattern_current.time++;
pattern_current.energy += x * x;
}
// get only from negative to positive
if (x > 0 && last_sample < 0) {
if (last_zero) delta = 1;
else delta = (double) x / (x - last_sample);
if (nb_frame_current > 0) {
nb_frame_current -= delta;
pattern.push_back(nb_frame_current);
if (pattern_current.time > 0) {
pattern_current.time -= delta;
pattern.push_back(pattern_current);
//cout << nb_frame_current << " ";
}
nb_frame_current = delta;
pattern_current.time = delta;
pattern_current.energy = x * x;
}
// drop 0 values to know sign change
if (x) last_sample = x, last_zero = false;
@ -119,7 +135,7 @@ template<typename sample_t> void ZeroCross<sample_t>::ComputeFrame(sample_t x)
// compute if window suffisent
if (nb_frame_analysed++ == nb_frame_to_analyse) {
auto res = FindPattern(pattern, sample_min, sample_max);
if (res.first) freq = rate / res.first;
if (res.time) freq = rate / res.time;
else freq = 0;
nb_frame_analysed = 0;
pattern.clear();

16
src/audio/ZeroCross.hpp
View file

@ -4,6 +4,18 @@
#include <stdint.h>
#include <vector>
namespace patterns {
struct Pattern {
double time, energy;
};
struct PatternMatch {
double time, time_deviation, energy_deviation;
PatternMatch() : time(0), time_deviation(0), energy_deviation(0) {}
};
};
template<typename sample_t> class ZeroCross {
public:
struct Config {
@ -14,11 +26,11 @@ template<typename sample_t> class ZeroCross {
private:
int rate, nb_frame_to_analyse, nb_frame_analysed, diff_x;
double nb_frame_current;
patterns::Pattern pattern_current;
int16_t last_sample;
double freq, sample_min, sample_max;
bool last_zero;
std::vector<double> pattern;
std::vector<patterns::Pattern> pattern;
inline void ComputeFrame(sample_t x);