+++ /dev/null
-/*
- * DTMF Receiver module, part of:
- * BSD Telephony Of Mexico "Zapata" Telecom Library, version 1.10 12/9/01
- *
- * Part of the "Zapata" Computer Telephony Technology.
- *
- * See http://www.bsdtelephony.com.mx
- *
- *
- * The technologies, software, hardware, designs, drawings, scheumatics, board
- * layouts and/or artwork, concepts, methodologies (including the use of all
- * of these, and that which is derived from the use of all of these), all other
- * intellectual properties contained herein, and all intellectual property
- * rights have been and shall continue to be expressly for the benefit of all
- * mankind, and are perpetually placed in the public domain, and may be used,
- * copied, and/or modified by anyone, in any manner, for any legal purpose,
- * without restriction.
- *
- * This module written by Stephen Underwood.
- */
-
-/*
- tone_detect.c - General telephony tone detection, and specific
- detection of DTMF.
-
- Copyright (C) 2001 Steve Underwood <steveu@coppice.org>
-
- Despite my general liking of the GPL, I place this code in the
- public domain for the benefit of all mankind - even the slimy
- ones who might try to proprietize my work and use it to my
- detriment.
-*/
-
-#include <math.h>
-#include <string.h>
-#include <stdio.h>
-#include <time.h>
-#include <fcntl.h>
-#include "tone_detect.h"
-
-#ifndef FALSE
-#define FALSE 0
-#endif
-#ifndef TRUE
-#define TRUE (!FALSE)
-#endif
-
-//#define USE_3DNOW
-
-/* Basic DTMF specs:
- *
- * Minimum tone on = 40ms
- * Minimum tone off = 50ms
- * Maximum digit rate = 10 per second
- * Normal twist <= 8dB accepted
- * Reverse twist <= 4dB accepted
- * S/N >= 15dB will detect OK
- * Attenuation <= 26dB will detect OK
- * Frequency tolerance +- 1.5% will detect, +-3.5% will reject
- */
-
-#define SAMPLE_RATE 8000.0
-
-#define DTMF_THRESHOLD 8.0e7
-#define FAX_THRESHOLD 8.0e7
-#define FAX_2ND_HARMONIC 2.0 /* 4dB */
-#define DTMF_NORMAL_TWIST 6.3 /* 8dB */
-#define DTMF_REVERSE_TWIST ((isradio) ? 4.0 : 2.5) /* 4dB normal */
-#define DTMF_RELATIVE_PEAK_ROW 6.3 /* 8dB */
-#define DTMF_RELATIVE_PEAK_COL 6.3 /* 8dB */
-#define DTMF_2ND_HARMONIC_ROW ((isradio) ? 1.7 : 2.5) /* 4dB normal */
-#define DTMF_2ND_HARMONIC_COL 63.1 /* 18dB */
-
-static tone_detection_descriptor_t dtmf_detect_row[4];
-static tone_detection_descriptor_t dtmf_detect_col[4];
-static tone_detection_descriptor_t dtmf_detect_row_2nd[4];
-static tone_detection_descriptor_t dtmf_detect_col_2nd[4];
-static tone_detection_descriptor_t fax_detect;
-static tone_detection_descriptor_t fax_detect_2nd;
-
-static float dtmf_row[] = {
- 697.0, 770.0, 852.0, 941.0
-};
-
-static float dtmf_col[] = {
- 1209.0, 1336.0, 1477.0, 1633.0
-};
-
-static float fax_freq = 1100.0;
-
-static char dtmf_positions[] = "123A" "456B" "789C" "*0#D";
-
-static void
-goertzel_init (goertzel_state_t * s, tone_detection_descriptor_t * t)
-{
- s->v2 = s->v3 = 0.0;
- s->fac = t->fac;
-}
-
-/*- End of function --------------------------------------------------------*/
-
-#if defined(USE_3DNOW)
-static inline void
-_dtmf_goertzel_update (goertzel_state_t * s, float x[], int samples)
-{
- int n;
- float v;
- int i;
- float vv[16];
-
- vv[4] = s[0].v2;
- vv[5] = s[1].v2;
- vv[6] = s[2].v2;
- vv[7] = s[3].v2;
- vv[8] = s[0].v3;
- vv[9] = s[1].v3;
- vv[10] = s[2].v3;
- vv[11] = s[3].v3;
- vv[12] = s[0].fac;
- vv[13] = s[1].fac;
- vv[14] = s[2].fac;
- vv[15] = s[3].fac;
-
- //v1 = s->v2;
- //s->v2 = s->v3;
- //s->v3 = s->fac*s->v2 - v1 + x[0];
-
- __asm__ __volatile__ (" femms;\n"
- " movq 16(%%edx),%%mm2;\n"
- " movq 24(%%edx),%%mm3;\n"
- " movq 32(%%edx),%%mm4;\n"
- " movq 40(%%edx),%%mm5;\n"
- " movq 48(%%edx),%%mm6;\n"
- " movq 56(%%edx),%%mm7;\n"
- " jmp 1f;\n"
- " .align 32;\n"
- " 1: ;\n"
- " prefetch (%%eax);\n"
- " movq %%mm3,%%mm1;\n"
- " movq %%mm2,%%mm0;\n"
- " movq %%mm5,%%mm3;\n"
- " movq %%mm4,%%mm2;\n"
- " pfmul %%mm7,%%mm5;\n"
- " pfmul %%mm6,%%mm4;\n"
- " pfsub %%mm1,%%mm5;\n"
- " pfsub %%mm0,%%mm4;\n"
- " movq (%%eax),%%mm0;\n"
- " movq %%mm0,%%mm1;\n"
- " punpckldq %%mm0,%%mm1;\n"
- " add $4,%%eax;\n"
- " pfadd %%mm1,%%mm5;\n"
- " pfadd %%mm1,%%mm4;\n"
- " dec %%ecx;\n"
- " jnz 1b;\n"
- " movq %%mm2,16(%%edx);\n"
- " movq %%mm3,24(%%edx);\n"
- " movq %%mm4,32(%%edx);\n"
- " movq %%mm5,40(%%edx);\n"
- " femms;\n"::"c" (samples), "a" (x), "d" (vv)
- :"memory", "eax", "ecx");
-
- s[0].v2 = vv[4];
- s[1].v2 = vv[5];
- s[2].v2 = vv[6];
- s[3].v2 = vv[7];
- s[0].v3 = vv[8];
- s[1].v3 = vv[9];
- s[2].v3 = vv[10];
- s[3].v3 = vv[11];
-}
-#endif
-/*- End of function --------------------------------------------------------*/
-
-void
-zap_goertzel_update (goertzel_state_t * s, int16_t x[], int samples)
-{
- int i;
- float v1;
-
- for (i = 0; i < samples; i++) {
- v1 = s->v2;
- s->v2 = s->v3;
- s->v3 = s->fac * s->v2 - v1 + x[i];
- }
-}
-
-/*- End of function --------------------------------------------------------*/
-
-float
-zap_goertzel_result (goertzel_state_t * s)
-{
- return s->v3 * s->v3 + s->v2 * s->v2 - s->v2 * s->v3 * s->fac;
-}
-
-/*- End of function --------------------------------------------------------*/
-
-void
-zap_dtmf_detect_init (dtmf_detect_state_t * s)
-{
- int i;
- float theta;
-
- s->hit1 = s->hit2 = 0;
-
- for (i = 0; i < 4; i++) {
- theta = 2.0 * G_PI * (dtmf_row[i] / SAMPLE_RATE);
- dtmf_detect_row[i].fac = 2.0 * cos (theta);
-
- theta = 2.0 * G_PI * (dtmf_col[i] / SAMPLE_RATE);
- dtmf_detect_col[i].fac = 2.0 * cos (theta);
-
- theta = 2.0 * G_PI * (dtmf_row[i] * 2.0 / SAMPLE_RATE);
- dtmf_detect_row_2nd[i].fac = 2.0 * cos (theta);
-
- theta = 2.0 * G_PI * (dtmf_col[i] * 2.0 / SAMPLE_RATE);
- dtmf_detect_col_2nd[i].fac = 2.0 * cos (theta);
-
- goertzel_init (&s->row_out[i], &dtmf_detect_row[i]);
- goertzel_init (&s->col_out[i], &dtmf_detect_col[i]);
- goertzel_init (&s->row_out2nd[i], &dtmf_detect_row_2nd[i]);
- goertzel_init (&s->col_out2nd[i], &dtmf_detect_col_2nd[i]);
-
- s->energy = 0.0;
- }
-
- /* Same for the fax dector */
- theta = 2.0 * G_PI * (fax_freq / SAMPLE_RATE);
- fax_detect.fac = 2.0 * cos (theta);
- goertzel_init (&s->fax_tone, &fax_detect);
-
- /* Same for the fax dector 2nd harmonic */
- theta = 2.0 * G_PI * (fax_freq * 2.0 / SAMPLE_RATE);
- fax_detect_2nd.fac = 2.0 * cos (theta);
- goertzel_init (&s->fax_tone2nd, &fax_detect_2nd);
-
- s->current_sample = 0;
- s->detected_digits = 0;
- s->lost_digits = 0;
- s->digits[0] = '\0';
- s->mhit = 0;
-}
-
-/*- End of function --------------------------------------------------------*/
-
-int
-zap_dtmf_detect (dtmf_detect_state_t * s,
- int16_t amp[], int samples, int isradio)
-{
-
- float row_energy[4];
- float col_energy[4];
- float fax_energy;
- float fax_energy_2nd;
- float famp;
- float v1;
- int i;
- int j;
- int sample;
- int best_row;
- int best_col;
- int hit;
- int limit;
-
- hit = 0;
- for (sample = 0; sample < samples; sample = limit) {
- /* 102 is optimised to meet the DTMF specs. */
- if ((samples - sample) >= (102 - s->current_sample))
- limit = sample + (102 - s->current_sample);
- else
- limit = samples;
-#if defined(USE_3DNOW)
- _dtmf_goertzel_update (s->row_out, amp + sample, limit - sample);
- _dtmf_goertzel_update (s->col_out, amp + sample, limit - sample);
- _dtmf_goertzel_update (s->row_out2nd, amp + sample, limit2 - sample);
- _dtmf_goertzel_update (s->col_out2nd, amp + sample, limit2 - sample);
- /* XXX Need to fax detect for 3dnow too XXX */
-#warning "Fax Support Broken"
-#else
- /* The following unrolled loop takes only 35% (rough estimate) of the
- time of a rolled loop on the machine on which it was developed */
- for (j = sample; j < limit; j++) {
- famp = amp[j];
-
- s->energy += famp * famp;
-
- /* With GCC 2.95, the following unrolled code seems to take about 35%
- (rough estimate) as long as a neat little 0-3 loop */
- v1 = s->row_out[0].v2;
- s->row_out[0].v2 = s->row_out[0].v3;
- s->row_out[0].v3 = s->row_out[0].fac * s->row_out[0].v2 - v1 + famp;
-
- v1 = s->col_out[0].v2;
- s->col_out[0].v2 = s->col_out[0].v3;
- s->col_out[0].v3 = s->col_out[0].fac * s->col_out[0].v2 - v1 + famp;
-
- v1 = s->row_out[1].v2;
- s->row_out[1].v2 = s->row_out[1].v3;
- s->row_out[1].v3 = s->row_out[1].fac * s->row_out[1].v2 - v1 + famp;
-
- v1 = s->col_out[1].v2;
- s->col_out[1].v2 = s->col_out[1].v3;
- s->col_out[1].v3 = s->col_out[1].fac * s->col_out[1].v2 - v1 + famp;
-
- v1 = s->row_out[2].v2;
- s->row_out[2].v2 = s->row_out[2].v3;
- s->row_out[2].v3 = s->row_out[2].fac * s->row_out[2].v2 - v1 + famp;
-
- v1 = s->col_out[2].v2;
- s->col_out[2].v2 = s->col_out[2].v3;
- s->col_out[2].v3 = s->col_out[2].fac * s->col_out[2].v2 - v1 + famp;
-
- v1 = s->row_out[3].v2;
- s->row_out[3].v2 = s->row_out[3].v3;
- s->row_out[3].v3 = s->row_out[3].fac * s->row_out[3].v2 - v1 + famp;
-
- v1 = s->col_out[3].v2;
- s->col_out[3].v2 = s->col_out[3].v3;
- s->col_out[3].v3 = s->col_out[3].fac * s->col_out[3].v2 - v1 + famp;
-
- v1 = s->col_out2nd[0].v2;
- s->col_out2nd[0].v2 = s->col_out2nd[0].v3;
- s->col_out2nd[0].v3 =
- s->col_out2nd[0].fac * s->col_out2nd[0].v2 - v1 + famp;
-
- v1 = s->row_out2nd[0].v2;
- s->row_out2nd[0].v2 = s->row_out2nd[0].v3;
- s->row_out2nd[0].v3 =
- s->row_out2nd[0].fac * s->row_out2nd[0].v2 - v1 + famp;
-
- v1 = s->col_out2nd[1].v2;
- s->col_out2nd[1].v2 = s->col_out2nd[1].v3;
- s->col_out2nd[1].v3 =
- s->col_out2nd[1].fac * s->col_out2nd[1].v2 - v1 + famp;
-
- v1 = s->row_out2nd[1].v2;
- s->row_out2nd[1].v2 = s->row_out2nd[1].v3;
- s->row_out2nd[1].v3 =
- s->row_out2nd[1].fac * s->row_out2nd[1].v2 - v1 + famp;
-
- v1 = s->col_out2nd[2].v2;
- s->col_out2nd[2].v2 = s->col_out2nd[2].v3;
- s->col_out2nd[2].v3 =
- s->col_out2nd[2].fac * s->col_out2nd[2].v2 - v1 + famp;
-
- v1 = s->row_out2nd[2].v2;
- s->row_out2nd[2].v2 = s->row_out2nd[2].v3;
- s->row_out2nd[2].v3 =
- s->row_out2nd[2].fac * s->row_out2nd[2].v2 - v1 + famp;
-
- v1 = s->col_out2nd[3].v2;
- s->col_out2nd[3].v2 = s->col_out2nd[3].v3;
- s->col_out2nd[3].v3 =
- s->col_out2nd[3].fac * s->col_out2nd[3].v2 - v1 + famp;
-
- v1 = s->row_out2nd[3].v2;
- s->row_out2nd[3].v2 = s->row_out2nd[3].v3;
- s->row_out2nd[3].v3 =
- s->row_out2nd[3].fac * s->row_out2nd[3].v2 - v1 + famp;
-
- /* Update fax tone */
- v1 = s->fax_tone.v2;
- s->fax_tone.v2 = s->fax_tone.v3;
- s->fax_tone.v3 = s->fax_tone.fac * s->fax_tone.v2 - v1 + famp;
-
- v1 = s->fax_tone.v2;
- s->fax_tone2nd.v2 = s->fax_tone2nd.v3;
- s->fax_tone2nd.v3 = s->fax_tone2nd.fac * s->fax_tone2nd.v2 - v1 + famp;
- }
-#endif
- s->current_sample += (limit - sample);
- if (s->current_sample < 102)
- continue;
-
- /* Detect the fax energy, too */
- fax_energy = zap_goertzel_result (&s->fax_tone);
-
- /* We are at the end of a DTMF detection block */
- /* Find the peak row and the peak column */
- row_energy[0] = zap_goertzel_result (&s->row_out[0]);
- col_energy[0] = zap_goertzel_result (&s->col_out[0]);
-
- for (best_row = best_col = 0, i = 1; i < 4; i++) {
- row_energy[i] = zap_goertzel_result (&s->row_out[i]);
- if (row_energy[i] > row_energy[best_row])
- best_row = i;
- col_energy[i] = zap_goertzel_result (&s->col_out[i]);
- if (col_energy[i] > col_energy[best_col])
- best_col = i;
- }
- hit = 0;
- /* Basic signal level test and the twist test */
- if (row_energy[best_row] >= DTMF_THRESHOLD
- &&
- col_energy[best_col] >= DTMF_THRESHOLD
- &&
- col_energy[best_col] < row_energy[best_row] * DTMF_REVERSE_TWIST
- && col_energy[best_col] * DTMF_NORMAL_TWIST > row_energy[best_row]) {
- /* Relative peak test */
- for (i = 0; i < 4; i++) {
- if ((i != best_col
- && col_energy[i] * DTMF_RELATIVE_PEAK_COL >
- col_energy[best_col])
- || (i != best_row
- && row_energy[i] * DTMF_RELATIVE_PEAK_ROW >
- row_energy[best_row])) {
- break;
- }
- }
- /* ... and second harmonic test */
- if (i >= 4
- &&
- (row_energy[best_row] + col_energy[best_col]) > 42.0 * s->energy
- &&
- zap_goertzel_result (&s->col_out2nd[best_col]) *
- DTMF_2ND_HARMONIC_COL < col_energy[best_col]
- && zap_goertzel_result (&s->row_out2nd[best_row]) *
- DTMF_2ND_HARMONIC_ROW < row_energy[best_row]) {
- hit = dtmf_positions[(best_row << 2) + best_col];
- /* Look for two successive similar results */
- /* The logic in the next test is:
- We need two successive identical clean detects, with
- something different preceeding it. This can work with
- back to back differing digits. More importantly, it
- can work with nasty phones that give a very wobbly start
- to a digit. */
- if (hit == s->hit3 && s->hit3 != s->hit2) {
- s->mhit = hit;
- s->digit_hits[(best_row << 2) + best_col]++;
- s->detected_digits++;
- if (s->current_digits < MAX_DTMF_DIGITS) {
- s->digits[s->current_digits++] = hit;
- s->digits[s->current_digits] = '\0';
- } else {
- s->lost_digits++;
- }
- }
- }
- }
- if (!hit && (fax_energy >= FAX_THRESHOLD)
- && (fax_energy > s->energy * 21.0)) {
- fax_energy_2nd = zap_goertzel_result (&s->fax_tone2nd);
- if (fax_energy_2nd * FAX_2ND_HARMONIC < fax_energy) {
-#if 0
- printf ("Fax energy/Second Harmonic: %f/%f\n", fax_energy,
- fax_energy_2nd);
-#endif
- /* XXX Probably need better checking than just this the energy XXX */
- hit = 'f';
- s->fax_hits++;
- } /* Don't reset fax hits counter */
- } else {
- if (s->fax_hits > 5) {
- s->mhit = 'f';
- s->detected_digits++;
- if (s->current_digits < MAX_DTMF_DIGITS) {
- s->digits[s->current_digits++] = hit;
- s->digits[s->current_digits] = '\0';
- } else {
- s->lost_digits++;
- }
- }
- s->fax_hits = 0;
- }
- s->hit1 = s->hit2;
- s->hit2 = s->hit3;
- s->hit3 = hit;
- /* Reinitialise the detector for the next block */
- for (i = 0; i < 4; i++) {
- goertzel_init (&s->row_out[i], &dtmf_detect_row[i]);
- goertzel_init (&s->col_out[i], &dtmf_detect_col[i]);
- goertzel_init (&s->row_out2nd[i], &dtmf_detect_row_2nd[i]);
- goertzel_init (&s->col_out2nd[i], &dtmf_detect_col_2nd[i]);
- }
- goertzel_init (&s->fax_tone, &fax_detect);
- goertzel_init (&s->fax_tone2nd, &fax_detect_2nd);
- s->energy = 0.0;
- s->current_sample = 0;
- }
- if ((!s->mhit) || (s->mhit != hit)) {
- s->mhit = 0;
- return (0);
- }
- return (hit);
-}
-
-/*- End of function --------------------------------------------------------*/
-
-int
-zap_dtmf_get (dtmf_detect_state_t * s, char *buf, int max)
-{
- if (max > s->current_digits)
- max = s->current_digits;
- if (max > 0) {
- memcpy (buf, s->digits, max);
- memmove (s->digits, s->digits + max, s->current_digits - max);
- s->current_digits -= max;
- }
- buf[max] = '\0';
- return max;
-}
-
-/*- End of function --------------------------------------------------------*/
-/*- End of file ------------------------------------------------------------*/