From 6e38dfa629db5d34071c7d891633fe5dae52a2f1 Mon Sep 17 00:00:00 2001 From: pp Date: Sun, 23 Mar 2008 17:38:12 +0000 Subject: - YIN estimator improvements: - minimum detection now operates on interpolated values - period calculation now interpolates raw difference function, as interpolation of the normalized function is said to be slightly biased - added high threshold parameter, above which the result is ignored (no note detected) git-svn-id: https://lampka.siedziba.pl:790/svn/repos/lingot-win32@314 455248ca-bdda-0310-9134-f4ebb693071a --- src/lingot-config.c | 15 +++++++------- src/lingot-config.h | 5 +++-- src/lingot-core.c | 2 +- src/lingot-yin.c | 58 +++++++++++++++++++++++++++++++++++------------------ src/lingot-yin.h | 2 +- 5 files changed, 51 insertions(+), 31 deletions(-) diff --git a/src/lingot-config.c b/src/lingot-config.c index e228540..898c56f 100644 --- a/src/lingot-config.c +++ b/src/lingot-config.c @@ -35,12 +35,12 @@ char* token[] = { "AUDIO_DEV", "SAMPLE_RATE", "OVERSAMPLING", "ROOT_FREQUENCY_ERROR", "MIN_FREQUENCY", "FFT_SIZE", "TEMPORAL_WINDOW", "NOISE_THRESHOLD", "CALCULATION_RATE", "VISUALIZATION_RATE", "PEAK_NUMBER", "PEAK_ORDER", - "PEAK_REJECTION_RELATION", "DFT_NUMBER", "DFT_SIZE", "YIN_THRESHOLD", - "ESTIMATOR", NULL // NULL terminated array + "PEAK_REJECTION_RELATION", "DFT_NUMBER", "DFT_SIZE", "YIN_THRESHOLD_LOW", + "YIN_THRESHOLD_HIGH", "ESTIMATOR", NULL // NULL terminated array }; // print/scan param formats. -const char* format = "sddffdffffddfddfd"; +const char* format = "sddffdffffddfddffd"; //---------------------------------------------------------------------------- @@ -59,10 +59,10 @@ LingotConfig* lingot_config_new() &config->noise_threshold_db, &config->calculation_rate, &config->visualization_rate, &config->peak_number, &config->peak_order, &config->peak_rejection_relation_db, - &config->dft_number, &config->dft_size, &config->yin_threshold, - &config->estimator }; + &config->dft_number, &config->dft_size, &config->yin_threshold_low, + &config->yin_threshold_high, &config->estimator }; - memcpy(config->param, c_param, 17*sizeof(void*)); + memcpy(config->param, c_param, 18*sizeof(void*)); return config; } @@ -100,7 +100,8 @@ void lingot_config_reset(LingotConfig* config) config->vr = -0.45; // near to minimum - config->yin_threshold = 0.1; + config->yin_threshold_low = 0.1; + config->yin_threshold_high = 0.2; config->estimator = 0; lingot_config_update_internal_params(config); diff --git a/src/lingot-config.h b/src/lingot-config.h index dcdc2bf..1d0fcaa 100644 --- a/src/lingot-config.h +++ b/src/lingot-config.h @@ -35,7 +35,7 @@ typedef struct _LingotConfig LingotConfig; struct _LingotConfig { - void* param[17]; // parameter pointer array. + void* param[18]; // parameter pointer array. char audio_dev[80]; // default "/dev/dsp" unsigned int sample_rate; // soundcard sample rate. @@ -83,7 +83,8 @@ struct _LingotConfig unsigned int dft_number; // number of DFTs. unsigned int dft_size; // samples of each DFT. - FLT yin_threshold; + FLT yin_threshold_low; + FLT yin_threshold_high; unsigned int estimator; // max iterations for Newton-Raphson algorithm. diff --git a/src/lingot-core.c b/src/lingot-core.c index 5f7584c..bef46c6 100644 --- a/src/lingot-core.c +++ b/src/lingot-core.c @@ -273,7 +273,7 @@ void lingot_core_process(LingotCore* core) { // ------------------------------------------ // - if (core->conf->estimator == 1) core->freq = core->conf->sample_rate / (FLT)core->conf->oversampling / yin(core); + if (core->conf->estimator == 1) yin(core); // ----------------- TRANSFORMATION TO FREQUENCY DOMAIN ---------------- diff --git a/src/lingot-yin.c b/src/lingot-yin.c index 05eaa59..42e478e 100644 --- a/src/lingot-yin.c +++ b/src/lingot-yin.c @@ -34,41 +34,59 @@ inline FLT yin_sqr(FLT x) return x*x; } -inline FLT yin_interpolate_tau(FLT y1, FLT y2, FLT y3) +inline FLT yin_interpolate_x(FLT y1, FLT y2, FLT y3) { + if ((y1 == y2) && (y2 == y3)) return 0; return ((y1 - y3)/(2.0*(y3 + y1 - (2.0*y2)))); } -FLT yin(LingotCore* core) { - FLT dt_tau; +inline FLT yin_interpolate_y(FLT y1, FLT y2, FLT y3) +{ + if ((y1 == y2) && (y2 == y3)) return y1; + return (((6.0 * y2) - y1 + (3.0 * y3) - (4.0 * yin_sqr(y2 - y3) / (y3 - (2.0 * y2) + y1))) / 8.0); +} + +void yin(LingotCore* core) { + FLT dt_tau[3]; FLT dt_tau_sum = 0; - FLT dpt_right = 1.0/0.0, dpt_center, dpt_left; - FLT thr = core->conf->yin_threshold; + FLT dpt[3]; + FLT thr_low = core->conf->yin_threshold_low; + FLT thr_high = core->conf->yin_threshold_high; FLT dpt_min = 1.0/0.0; - FLT dpt_min_left, dpt_min_right; - int j, tau, tau_min; + FLT dpt_interpolated; + FLT tau_min; + int j, tau; int len = core->conf->temporal_buffer_size / 2; - for (tau = 1; (tau < len) && ((dpt_center > thr) || (dpt_right < dpt_center) || (tau <= 2)); tau++) + for (tau = 1; tau < len; tau++) { - dt_tau = 0; + dt_tau[0] = dt_tau[1]; + dt_tau[1] = dt_tau[2]; + dt_tau[2] = 0; for (j = 0; j < len ; j++) { - dt_tau += yin_sqr(core->temporal_buffer[j] - core->temporal_buffer[j+tau]); + dt_tau[2] += yin_sqr(core->temporal_buffer[j] - core->temporal_buffer[j+tau]); } - dt_tau_sum += dt_tau; + dt_tau_sum += dt_tau[2]; - dpt_left = dpt_center; - dpt_center = dpt_right; - dpt_right = dt_tau / ( 1.0 / tau * dt_tau_sum ); + dpt[0] = dpt[1]; + dpt[1] = dpt[2]; + dpt[2] = dt_tau[2] / ( 1.0 / tau * dt_tau_sum ); - if (dpt_center < dpt_min) + if (tau >= 3) { - dpt_min_left = dpt_left; - dpt_min = dpt_center; - dpt_min_right = dpt_right; - tau_min = tau - 1; + if ((dpt[1] <= dpt[0]) && (dpt[1] <= dpt[2])) + { +// we have local minimum + dpt_interpolated = yin_interpolate_y(dpt[0], dpt[1], dpt[2]); + if (dpt_interpolated < dpt_min) + { + dpt_min = dpt_interpolated; + tau_min = (FLT)tau - 1 + yin_interpolate_x(dt_tau[0], dt_tau[1], dt_tau[2]); + if (dpt_min < thr_low) break; + } + } } } - return (FLT)tau_min + yin_interpolate_tau(dpt_min_left, dpt_min, dpt_min_right); + if ((tau_min > 1) && (dpt_min < thr_high)) core->freq = core->conf->sample_rate / (FLT)core->conf->oversampling / tau_min; else core->freq = 0; } diff --git a/src/lingot-yin.h b/src/lingot-yin.h index 1109c22..040ef0d 100644 --- a/src/lingot-yin.h +++ b/src/lingot-yin.h @@ -26,6 +26,6 @@ #include "lingot-core.h" // returns detected period as a number of samples -FLT yin(LingotCore* core); +void yin(LingotCore* core); #endif -- cgit v1.2.3