ref: 5a3edce57e604c0a54d7373619b65c2d9ec46881
parent: fc724b42fe0d335f2124f49bcfc1c38e887072bc
author: robs <robs>
date: Sat Jun 13 11:23:08 EDT 2009
vad updates
--- a/ChangeLog
+++ b/ChangeLog
@@ -85,6 +85,7 @@
o New `fir' filter effect using external coefficients/file. (robs)
o New `biquad' filter effect using external coefficients. (robs)
o New `overdrive' effect. (robs)
+ o New `vad' Voice Activity Detector effect (undocumented as yet). (robs)
o `synth' enhancements: can now set common parameters for multiple
channels, new `pluck' and `tpdf' types, `scientific' note
notation, [2778142] just intonation. (robs)
--- a/FEATURES.in
+++ b/FEATURES.in
@@ -92,7 +92,7 @@
** silence: Remove portions of silence from the audio
** splice: Perform the equivalent of a cross-faded tape splice
** trim: Trim the ends of the audio
-** vad+: Prototype `silence' variant (W.I.P.)
+** vad: Voice activity detector
* Mixing effects
** channels: Auto mix or duplicate to change number of channels
--- a/src/vad.c
+++ b/src/vad.c
@@ -20,58 +20,72 @@
#include <string.h>
typedef struct {- double last_meas;
- double meas, slope1, slope2; /* TC -controlled */
+ double * dft_buf, * noise_buf, * spectrum, * meas_buf, mean_meas;
} chan_t;
typedef struct { /* Configuration parameters: */- double hp_freq, lp_freq, measure_freq, search_step_time;
- double measure_duration, search_time, pre_trigger_time, trigger_level;
- double trigger_tc, slope_tc1, slope_tc2;
+ double noise_tc_up, noise_tc_down, noise_reduction_amount;
+ double measure_freq, measure_duration, measure_tc, pre_trigger_time;
+ double hp_filter_freq, lp_filter_freq, hp_lifter_freq, lp_lifter_freq;
+ double trigger_tc, trigger_level1, search_time, gap_time;
/* Working variables: */
sox_sample_t * buffer;
- unsigned search_len, buffer_len, buffer_ptr, flush_done, search_step_len;
-
- double * dft_buf, * window1, * window2;
- unsigned dft_len, measure_period, measure_timer, measure_len;
- chan_t * channels;
- double trigger_meas_tc_mult, trigger_slope_tc_mult1, trigger_slope_tc_mult2;
- double search_slope_tc_mult1, search_slope_tc_mult2;
- unsigned start_bin, end_bin;
+ unsigned dft_len, buffer_len, buffer_ptr, flush_done, gap_count;
+ unsigned measure_period_len, measure_len, search_count, search_ptr;
+ unsigned spectrum_start, spectrum_end, cepstrum_start, cepstrum_end;
+ int measure_timer, booting;
+ double measure_tc_mult, trigger_meas_tc_mult;
+ double noise_tc_up_mult, noise_tc_down_mult;
+ double * spectrum_window, * cepstrum_window;
+ chan_t * channels;
} priv_t;
+#define GETOPT_FREQ(c, name, min) \
+ case c: p->name = lsx_parse_frequency(lsx_optarg, &parse_ptr); \
+ if (p->name < min || *parse_ptr) return lsx_usage(effp); \
+ break;
+
static int create(sox_effect_t * effp, int argc, char * * argv)
{priv_t * p = (priv_t *)effp->priv;
+ #define opt_str "+N:n:r:f:m:M:h:l:H:L:T:t:s:g:p:"
int c;
- p->hp_freq = 120;
- p->lp_freq = 12500;
- p->measure_duration = .2;
- p->measure_freq = 10;
- p->trigger_tc = .2;
- p->trigger_level = 33;
+ p->noise_tc_up = .1;
+ p->noise_tc_down = .01;
+ p->noise_reduction_amount = 1.35;
+
+ p->measure_freq = 20;
+ p->measure_duration = 2 / p->measure_freq;
+ p->measure_tc = .4;
+
+ p->hp_filter_freq = 50;
+ p->lp_filter_freq = 6000;
+ p->hp_lifter_freq = 150;
+ p->lp_lifter_freq = 2000;
+
+ p->trigger_tc = .25;
+ p->trigger_level1 = 7;
+
p->search_time = 1;
- p->search_step_time = .05;
- p->slope_tc1 = .35;
- p->slope_tc2 = .075;
+ p->gap_time = .25;
- while ((c = lsx_getopt(argc, argv, "+h:l:m:f:T:t:s:q:S:F:p:")) != -1) switch (c) {+ while ((c = lsx_getopt(argc, argv, opt_str)) != -1) switch (c) {char * parse_ptr;
- case 'h': p->hp_freq = lsx_parse_frequency(lsx_optarg, &parse_ptr);
- if (p->hp_freq < 10 || *parse_ptr) return lsx_usage(effp);
- break;
- case 'l': p->lp_freq = lsx_parse_frequency(lsx_optarg, &parse_ptr);
- if (p->lp_freq < 1000 || *parse_ptr) return lsx_usage(effp);
- break;
- GETOPT_NUMERIC('m', measure_duration, .02, 2)- GETOPT_NUMERIC('f', measure_freq , 1 ,100)- GETOPT_NUMERIC('T', trigger_tc , .001, 1)- GETOPT_NUMERIC('t', trigger_level , 0, 100)- GETOPT_NUMERIC('s', search_time , 0 , 4)- GETOPT_NUMERIC('q', search_step_time, .002, .02)- GETOPT_NUMERIC('S', slope_tc1 , .001, 1)- GETOPT_NUMERIC('F', slope_tc2 , .001, 1)+ GETOPT_NUMERIC('N', noise_tc_up , .1 , 10)+ GETOPT_NUMERIC('n', noise_tc_down ,.001 , .1)+ GETOPT_NUMERIC('r', noise_reduction_amount ,0 , 2)+ GETOPT_NUMERIC('f', measure_freq , 5 , 50)+ GETOPT_NUMERIC('m', measure_duration, .01 , 1)+ GETOPT_NUMERIC('M', measure_tc , .1 , 1)+ GETOPT_FREQ( 'h', hp_filter_freq , 10)
+ GETOPT_FREQ( 'l', lp_filter_freq , 1000)
+ GETOPT_FREQ( 'H', hp_lifter_freq , 10)
+ GETOPT_FREQ( 'L', lp_lifter_freq , 1000)
+ GETOPT_NUMERIC('T', trigger_tc , .01 , 1)+ GETOPT_NUMERIC('t', trigger_level1 , 0 , 10)+ GETOPT_NUMERIC('s', search_time , .1 , 4)+ GETOPT_NUMERIC('g', gap_time , .1 , 1) GETOPT_NUMERIC('p', pre_trigger_time, 0 , 4) default: lsx_fail("invalid option `-%c'", optopt); return lsx_usage(effp);}
@@ -81,48 +95,63 @@
static int start(sox_effect_t * effp)
{priv_t * p = (priv_t *)effp->priv;
- unsigned i;
+ unsigned i, pre_trigger_len, search_len;
- unsigned pre_trigger_len = p->pre_trigger_time * effp->in_signal.rate + .5;
+ pre_trigger_len = p->pre_trigger_time * effp->in_signal.rate + .5;
pre_trigger_len *= effp->in_signal.channels;
p->measure_len = effp->in_signal.rate * p->measure_duration + .5;
p->measure_len *= effp->in_signal.channels;
- p->search_step_len = effp->in_signal.rate * p->search_step_time + .5;
- p->search_step_len *= effp->in_signal.channels;
- p->search_len = p->search_time * effp->in_signal.rate + .5;
- p->search_len *= effp->in_signal.channels;
- p->search_len += p->measure_len;
+ p->measure_period_len = effp->in_signal.rate / p->measure_freq + .5;
+ p->measure_period_len *= effp->in_signal.channels;
+ p->search_count = ceil(p->search_time * p->measure_freq);
+ search_len = p->search_count * p->measure_period_len;
+ p->gap_count = p->gap_time * p->measure_freq + .5;
- p->buffer_len = pre_trigger_len + p->search_len;
- p->buffer = lsx_calloc(p->buffer_len, sizeof(*p->buffer));
+ p->buffer_len = pre_trigger_len + p->measure_len + search_len;
+ lsx_Calloc(p->buffer, p->buffer_len);
for (p->dft_len = 16; p->dft_len < p->measure_len; p->dft_len <<= 1);
- p->dft_buf = lsx_calloc(p->dft_len, sizeof(*p->dft_buf));
+ lsx_debug("dft_len=%u measure_len=%u", p->dft_len, p->measure_len);- p->window1 = lsx_calloc(p->measure_len, sizeof(*p->window1));
+ lsx_Calloc(p->channels, effp->in_signal.channels);
+ for (i = 0; i < effp->in_signal.channels; ++i) {+ chan_t * c = &p->channels[i];
+ lsx_Calloc(c->dft_buf, p->dft_len);
+ lsx_Calloc(c->spectrum, p->dft_len);
+ lsx_Calloc(c->noise_buf, p->dft_len);
+ lsx_Calloc(c->meas_buf, p->search_count);
+ }
+
+ lsx_Calloc(p->spectrum_window, p->measure_len);
for (i = 0; i < p->measure_len; ++i)
- p->window1[i] = -2. / SOX_SAMPLE_MIN / p->measure_len;
- lsx_apply_hann(p->window1, (int)p->measure_len);
+ p->spectrum_window[i] = -2. / SOX_SAMPLE_MIN / sqrt((double)p->measure_len);
+ lsx_apply_hann(p->spectrum_window, (int)p->measure_len);
- p->start_bin = p->hp_freq / effp->in_signal.rate * p->dft_len + .5;
- p->end_bin = p->lp_freq / effp->in_signal.rate * p->dft_len + .5;
- p->end_bin = min(p->end_bin, p->dft_len / 2);
- p->window2 = lsx_calloc(p->end_bin - p->start_bin, sizeof(*p->window2));
- for (i = 0; i < p->end_bin - p->start_bin; ++i)
- p->window2[i] = 2 * (p->dft_len / 2 + 1.) / (p->end_bin - p->start_bin);
- lsx_apply_hann(p->window2, (int)(p->end_bin - p->start_bin));
+ p->spectrum_start = p->hp_filter_freq / effp->in_signal.rate * p->dft_len + .5;
+ p->spectrum_start = max(p->spectrum_start, 1);
+ p->spectrum_end = p->lp_filter_freq / effp->in_signal.rate * p->dft_len + .5;
+ p->spectrum_end = min(p->spectrum_end, p->dft_len / 2);
+ lsx_Calloc(p->cepstrum_window, p->spectrum_end - p->spectrum_start);
+ for (i = 0; i < p->spectrum_end - p->spectrum_start; ++i)
+ p->cepstrum_window[i] = 2 / sqrt((double)p->spectrum_end - p->spectrum_start);
+ lsx_apply_hann(p->cepstrum_window, (int)(p->spectrum_end - p->spectrum_start));
+
+ p->cepstrum_start = ceil(effp->in_signal.rate * .5 / p->lp_lifter_freq);
+ p->cepstrum_end = floor(effp->in_signal.rate * .5 / p->hp_lifter_freq);
+ p->cepstrum_end = min(p->cepstrum_end, p->dft_len / 4);
+ if (p->cepstrum_end <= p->cepstrum_start)
+ return SOX_EOF;
+
+ p->noise_tc_up_mult = exp(-1 / (p->noise_tc_up * p->measure_freq));
+ p->noise_tc_down_mult = exp(-1 / (p->noise_tc_down * p->measure_freq));
+ p->measure_tc_mult = exp(-1 / (p->measure_tc * p->measure_freq));
+ p->trigger_meas_tc_mult = exp(-1 / (p->trigger_tc * p->measure_freq));
+
+ p->measure_timer = -p->measure_len;
p->flush_done = p->buffer_ptr = 0;
- p->measure_period = effp->in_signal.rate / p->measure_freq + .5;
- p->channels = lsx_calloc(effp->in_signal.channels, sizeof(*p->channels));
- p->trigger_meas_tc_mult = exp(-1 / (p->trigger_tc * p->measure_freq));
- p->trigger_slope_tc_mult1 = exp(-1 / (p->slope_tc1 * p->measure_freq));
- p->trigger_slope_tc_mult2 = exp(-1 / (p->slope_tc2 * p->measure_freq));
- p->search_slope_tc_mult1 = exp(-1 / (p->slope_tc1 / p->search_step_time));
- p->search_slope_tc_mult2 = exp(-1 / (p->slope_tc2 / p->search_step_time));
- lsx_debug("dft_len=%u measure_len=%u", p->dft_len, p->measure_len);return SOX_SUCCESS;
}
@@ -148,37 +177,36 @@
return SOX_SUCCESS;
}
-static double measure(sox_effect_t * effp, size_t x)
+static double measure(
+ priv_t * p, chan_t * c, size_t index, size_t step, int booting)
{- priv_t * p = (priv_t *)effp->priv;
- double * buf = p->dft_buf;
double mult, result = 0;
- size_t i, n;
+ size_t i;
- for (i = 0; i < p->measure_len; ++i) {- buf[i] = p->buffer[x] * p->window1[i];
- x = (x + effp->in_signal.channels) % p->buffer_len;
+ for (i = 0; i < p->measure_len; ++i, index = (index + step) % p->buffer_len)
+ c->dft_buf[i] = p->buffer[index] * p->spectrum_window[i];
+ memset(c->dft_buf + i, 0, (p->dft_len - i) * sizeof(*c->dft_buf));
+ lsx_safe_rdft((int)p->dft_len, 1, c->dft_buf);
+
+ memset(c->dft_buf, 0, p->spectrum_start * sizeof(*c->dft_buf));
+ for (i = p->spectrum_start; i < p->spectrum_end; ++i) {+ double d = sqrt(sqr(c->dft_buf[2 * i]) + sqr(c->dft_buf[2 * i + 1]));
+ mult = booting >= 0? booting / (1. + booting) : p->measure_tc_mult;
+ c->spectrum[i] = c->spectrum[i] * mult + d * (1 - mult);
+ d = sqr(c->spectrum[i]);
+ mult = booting >= 0? 0 :
+ d > c->noise_buf[i]? p->noise_tc_up_mult : p->noise_tc_down_mult;
+ c->noise_buf[i] = c->noise_buf[i] * mult + d * (1 - mult);
+ d = sqrt(max(0, d - p->noise_reduction_amount * c->noise_buf[i]));
+ c->dft_buf[i] = d * p->cepstrum_window[i - p->spectrum_start];
}
- memset(buf + i, 0, (p->dft_len - i) * sizeof(*buf));
- lsx_safe_rdft((int)p->dft_len, 1, buf);
+ memset(c->dft_buf + i, 0, ((p->dft_len >> 1) - i) * sizeof(*c->dft_buf));
+ lsx_safe_rdft((int)p->dft_len >> 1, 1, c->dft_buf);
- memset(buf, 0, p->start_bin * sizeof(*buf));
- for (i = p->start_bin; i < p->end_bin; ++i)
- buf[i] = (sqr(buf[2*i]) + sqr(buf[2*i+1])) * p->window2[i-p->start_bin];
- memset(buf + i, 0, ((p->dft_len >> 1) - i) * sizeof(*buf));
- lsx_safe_rdft((int)p->dft_len >> 1, 1, buf);
-
- i = max(1, (size_t)(.006 * p->dft_len + .5));
- n = (size_t)(.014 * p->dft_len + .5);
- mult = (p->dft_len / 4 + 1.) / (n - i);
- for (; i < n; ++i)
- result += sqr(buf[2*i]) + sqr(buf[2*i+1]);
- result = log(mult * result);
- result = max(result + 50, 0);
-#if 0
- fprintf(stderr, "%g\n", result);
-#endif
- return result;
+ for (i = p->cepstrum_start; i < p->cepstrum_end; ++i)
+ result += sqr(c->dft_buf[2 * i]) + sqr(c->dft_buf[2 * i + 1]);
+ result = log(result / (p->cepstrum_end - p->cepstrum_start));
+ return max(0, 21 + result);
}
static int flow_trigger(sox_effect_t * effp, sox_sample_t const * ibuf,
@@ -189,59 +217,43 @@
size_t i, idone = 0, to_flush = 0;
while (idone < *ilen && !triggered) {+ p->measure_timer += effp->in_signal.channels;
for (i = 0; i < effp->in_signal.channels; ++i, ++idone) {chan_t * c = &p->channels[i];
p->buffer[p->buffer_ptr++] = *ibuf++;
- if (p->measure_timer == p->measure_period - 1) {- size_t flush = p->measure_len;
- size_t x = (p->buffer_ptr + p->buffer_len - flush) % p->buffer_len;
- double slope, meas, meas0 = measure(effp, x);
- c->meas = c->meas * p->trigger_meas_tc_mult + meas0 *(1 - p->trigger_meas_tc_mult);
- if (c->last_meas) {- slope = (meas0 - c->last_meas) * p->measure_freq;
- c->slope1 = c->slope1? c->slope1 * p->trigger_slope_tc_mult1 + slope
- * (1 - p->trigger_slope_tc_mult1) : slope;
- c->slope2 = c->slope2? c->slope2 * p->trigger_slope_tc_mult2 + slope
- * (1 - p->trigger_slope_tc_mult2) : slope;
+ if (!p->measure_timer) {+ size_t x = (p->buffer_ptr + p->buffer_len - p->measure_len) % p->buffer_len;
+ double meas = measure(p, c, x, effp->in_signal.channels, p->booting);
+ c->meas_buf[p->search_ptr] = meas;
+ c->mean_meas = c->mean_meas * p->trigger_meas_tc_mult +
+ meas *(1 - p->trigger_meas_tc_mult);
+
+ if (triggered |= c->mean_meas > p->trigger_level1) {+ unsigned n = p->search_count, ptr = p->search_ptr;
+ unsigned j, trigger_j = n, zero_j = n;
+ for (j = 0; j < n; ++j, ptr = (ptr + n - 1) % n)
+ if (c->meas_buf[ptr] > p->trigger_level1 && j <= trigger_j + p->gap_count)
+ zero_j = trigger_j = j;
+ else if (!c->meas_buf[ptr] && trigger_j >= zero_j)
+ zero_j = j;
+ j = min(j, zero_j);
+ to_flush = range_limit(j, to_flush, n);
}
- c->last_meas = meas0;
-#if 0
- if (c->meas)
- fprintf(stderr, "%g\n", c->meas);
-#endif
- if (triggered |= c->meas > p->trigger_level) {- sox_bool started = sox_false;
- do {- x = (x + p->buffer_len - p->search_step_len) % p->buffer_len;
- flush += p->search_step_len;
- meas = measure(effp, x);
-#if 0
- fprintf(stderr, "%g %g %g\n", meas, c->slope1, c->slope2);
-#endif
- slope = -(meas - c->last_meas) / p->search_step_time;
- c->last_meas = meas;
- if (slope > 0 || started) {- c->slope1 = c->slope1 * p->search_slope_tc_mult1 +
- slope * (1 - p->search_slope_tc_mult1);
- c->slope2 = c->slope2 * p->search_slope_tc_mult2 +
- slope * (1 - p->search_slope_tc_mult2);
- started = sox_true;
- }
- } while (flush < p->search_len && (
- (meas > p->trigger_level - 12 && (c->slope1 > 4 || c->slope2 > 2)) ||
- meas > p->trigger_level));
- to_flush = range_limit(flush, to_flush, p->search_len);
- }
+ lsx_debug_more("%12g %12g %u", meas, c->mean_meas, to_flush);}
}
if (p->buffer_ptr == p->buffer_len)
p->buffer_ptr = 0;
- if (++p->measure_timer == p->measure_period)
- p->measure_timer = 0;
+ if (!p->measure_timer) {+ p->measure_timer = -p->measure_period_len;
+ p->search_ptr = (p->search_ptr + 1) % p->search_count;
+ if (p->booting >= 0)
+ p->booting = p->booting == 6? -1 : p->booting + 1;
+ }
}
if (triggered) {size_t ilen1 = *ilen - idone;
- p->flush_done = p->search_len - to_flush;
+ p->flush_done = (p->search_count - to_flush) * p->measure_period_len;
p->buffer_ptr = (p->buffer_ptr + p->flush_done) % p->buffer_len;
(effp->handler.flow = flow_flush)(effp, ibuf, obuf, &ilen1, olen);
idone += ilen1;
@@ -260,10 +272,18 @@
static int stop(sox_effect_t * effp)
{priv_t * p = (priv_t *)effp->priv;
+ unsigned i;
+
+ for (i = 0; i < effp->in_signal.channels; ++i) {+ chan_t * c = &p->channels[i];
+ free(c->meas_buf);
+ free(c->noise_buf);
+ free(c->spectrum);
+ free(c->dft_buf);
+ }
free(p->channels);
- free(p->window2);
- free(p->window1);
- free(p->dft_buf);
+ free(p->cepstrum_window);
+ free(p->spectrum_window);
free(p->buffer);
return SOX_SUCCESS;
}
@@ -270,20 +290,29 @@
sox_effect_handler_t const * lsx_vad_effect_fn(void)
{- static sox_effect_handler_t handler = {"vad", "[options]"- "\n\t-h high-pass-filter (300 Hz)"
- "\n\t-l low-pass-filter (12500 Hz)"
- "\n\t-m measure-duration (0.2 s)"
- "\n\t-f measure-frequency (10 Hz)"
- "\n\t-T trigger-time-constant (0.2 s)"
- "\n\t-t trigger-level (33)"
- "\n\t-s search-time (1 s)"
- "\n\t-q search-step-time (0.05 s)"
- "\n\t-S slope-slow-time-constant (0.35 s)"
- "\n\t-F slope-fast-time-constant (0.075 s)"
- "\n\t-p pre-trigger-buffer (0 s)"
- , SOX_EFF_MCHAN | SOX_EFF_LENGTH | SOX_EFF_MODIFY | SOX_EFF_ALPHA,
+ static sox_effect_handler_t handler = {"vad", NULL,+ SOX_EFF_MCHAN | SOX_EFF_LENGTH | SOX_EFF_MODIFY,
create, start, flow_trigger, drain, stop, NULL, sizeof(priv_t)
};
+ static char const * lines[] = {+ "[options]",
+ "\t-N noise-tc-up (0.1 s)",
+ "\t-n noise-tc-down (0.01 s)",
+ "\t-r noise-reduction-amount (1.35)",
+ "\t-f measure-frequency (20 Hz)",
+ "\t-m measure-duration (0.1 s)",
+ "\t-M measure-tc (0.4 s)",
+ "\t-h high-pass-filter (50 Hz)",
+ "\t-l low-pass-filter (6000 Hz)",
+ "\t-H high-pass-lifter (150 Hz)",
+ "\t-L low-pass-lifter (2000 Hz)",
+ "\t-T trigger-time-constant (0.25 s)",
+ "\t-t trigger-level (7)",
+ "\t-s search-time (1 s)",
+ "\t-g allowed-gap (0.25 s)",
+ "\t-p pre-trigger-buffer (0 s)",
+ };
+ static char * usage;
+ handler.usage = lsx_usage_lines(&usage, lines, array_length(lines));
return &handler;
}