audiostuff: spandsp-0.0.3/spandsp-0.0.3/src/super_tone

comparison spandsp-0.0.3/spandsp-0.0.3/src/super_tone_rx.c @ 5:f762bf195c4b

import spandsp-0.0.3

author	Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date	Fri, 25 Jun 2010 16:00:21 +0200
parents
children

comparison

equal deleted inserted replaced

-:26cd8f1ef0b1
+:f762bf195c4b
+/*
+* SpanDSP - a series of DSP components for telephony
+*
+* super_tone_rx.c - Flexible telephony supervisory tone detection.
+*
+* Written by Steve Underwood <steveu@coppice.org>
+*
+* Copyright (C) 2003 Steve Underwood
+*
+* All rights reserved.
+*
+* This program is free software; you can redistribute it and/or modify
+* it under the terms of the GNU General Public License version 2, as
+* published by the Free Software Foundation.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software
+* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*
+* $Id: super_tone_rx.c,v 1.13 2006/11/19 14:07:25 steveu Exp $
+*/
+/*! \file */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <time.h>
+#include <inttypes.h>
+#if defined(HAVE_TGMATH_H)
+#include <tgmath.h>
+#endif
+#if defined(HAVE_MATH_H)
+#include <math.h>
+#endif
+#include "spandsp/telephony.h"
+#include "spandsp/tone_detect.h"
+#include "spandsp/tone_generate.h"
+#include "spandsp/super_tone_rx.h"
+#define THRESHOLD               8.0e7
+static int add_super_tone_freq(super_tone_rx_descriptor_t *desc, int freq)
+{
+int i;
+if (freq == 0)
+return -1;
+/* Look for an existing frequency */
+for (i = 0;  i < desc->used_frequencies;  i++)
+{
+if (desc->pitches[i][0] == freq)
+return desc->pitches[i][1];
+}
+/* Look for an existing tone which is very close. We may need to merge
+the detectors. */
+for (i = 0;  i < desc->used_frequencies;  i++)
+{
+if ((desc->pitches[i][0] - 10) <= freq  &&  freq <= (desc->pitches[i][0] + 10))
+{
+/* Merge these two */
+desc->pitches[desc->used_frequencies][0] = freq;
+desc->pitches[desc->used_frequencies][1] = i;
+make_goertzel_descriptor(&desc->desc[desc->pitches[i][1]], (float) (freq + desc->pitches[i][0])/2, BINS);
+desc->used_frequencies++;
+return desc->pitches[i][1];
+}
+}
+desc->pitches[i][0] = freq;
+desc->pitches[i][1] = desc->monitored_frequencies;
+if (desc->monitored_frequencies%5 == 0)
+{
+desc->desc = (goertzel_descriptor_t *) realloc(desc->desc, (desc->monitored_frequencies + 5)*sizeof(goertzel_descriptor_t));
+}
+make_goertzel_descriptor(&desc->desc[desc->monitored_frequencies++], (float) freq, BINS);
+desc->used_frequencies++;
+return desc->pitches[i][1];
+}
+/*- End of function --------------------------------------------------------*/
+int super_tone_rx_add_tone(super_tone_rx_descriptor_t *desc)
+{
+if (desc->tones%5 == 0)
+{
+desc->tone_list = (super_tone_rx_segment_t **) realloc(desc->tone_list, (desc->tones + 5)*sizeof(super_tone_rx_segment_t *));
+desc->tone_segs = (int *) realloc(desc->tone_segs, (desc->tones + 5)*sizeof(int));
+}
+desc->tone_list[desc->tones] = NULL;
+desc->tone_segs[desc->tones] = 0;
+desc->tones++;
+return desc->tones - 1;
+}
+/*- End of function --------------------------------------------------------*/
+int super_tone_rx_add_element(super_tone_rx_descriptor_t *desc,
+int tone,
+int f1,
+int f2,
+int min,
+int max)
+{
+int step;
+step = desc->tone_segs[tone];
+if (step%5 == 0)
+{
+desc->tone_list[tone] = (super_tone_rx_segment_t *) realloc(desc->tone_list[tone], (step + 5)*sizeof(super_tone_rx_segment_t));
+}
+desc->tone_list[tone][step].f1 = add_super_tone_freq(desc, f1);
+desc->tone_list[tone][step].f2 = add_super_tone_freq(desc, f2);
+desc->tone_list[tone][step].min_duration = min*8;
+desc->tone_list[tone][step].max_duration = (max == 0)  ?  0x7FFFFFFF  :  max*8;
+desc->tone_segs[tone]++;
+return step;
+}
+/*- End of function --------------------------------------------------------*/
+static int test_cadence(super_tone_rx_segment_t *pattern,
+int steps,
+super_tone_rx_segment_t *test,
+int rotation)
+{
+int i;
+int j;
+if (rotation >= 0)
+{
+/* Check only for the sustaining of a tone in progress. This means
+we only need to check each block if the latest step is compatible
+with the tone template. */
+if (steps < 0)
+{
+/* A -ve value for steps indicates we just changed step, and need to
+check the last one ended within spec. If we don't do this
+extra test a low duration segment might be accepted as OK. */
+steps = -steps;
+j = (rotation + steps - 2)%steps;
+if (pattern[j].f1 != test[8].f1  ||  pattern[j].f2 != test[8].f2)
+return  0;
+if (pattern[j].min_duration > test[8].min_duration*BINS
+||
+pattern[j].max_duration < test[8].min_duration*BINS)
+{
+return  0;
+}
+}
+j = (rotation + steps - 1)%steps;
+if (pattern[j].f1 != test[9].f1  ||  pattern[j].f2 != test[9].f2)
+return  0;
+if (pattern[j].max_duration < test[9].min_duration*BINS)
+return  0;
+}
+else
+{
+/* Look for a complete template match. */
+for (i = 0;  i < steps;  i++)
+{
+j = i + 10 - steps;
+if (pattern[i].f1 != test[j].f1  ||  pattern[i].f2 != test[j].f2)
+return  0;
+if (pattern[i].min_duration > test[j].min_duration*BINS
+||
+pattern[i].max_duration < test[j].min_duration*BINS)
+{
+return  0;
+}
+}
+}
+return  1;
+}
+/*- End of function --------------------------------------------------------*/
+super_tone_rx_descriptor_t *super_tone_rx_make_descriptor(super_tone_rx_descriptor_t *desc)
+{
+if (desc == NULL)
+{
+desc = (super_tone_rx_descriptor_t *) malloc(sizeof(super_tone_rx_descriptor_t));
+if (desc == NULL)
+return NULL;
+}
+desc->tone_list = NULL;
+desc->tone_segs = NULL;
+desc->used_frequencies = 0;
+desc->monitored_frequencies = 0;
+desc->desc = NULL;
+desc->tones = 0;
+return desc;
+}
+/*- End of function --------------------------------------------------------*/
+int super_tone_rx_free_descriptor(super_tone_rx_descriptor_t *desc)
+{
+if (desc)
+free(desc);
+return 0;
+}
+/*- End of function --------------------------------------------------------*/
+void super_tone_rx_segment_callback(super_tone_rx_state_t *s,
+void (*callback)(void *data, int f1, int f2, int duration))
+{
+s->segment_callback = callback;
+}
+/*- End of function --------------------------------------------------------*/
+super_tone_rx_state_t *super_tone_rx_init(super_tone_rx_state_t *s,
+super_tone_rx_descriptor_t *desc,
+tone_report_func_t callback,
+void *user_data)
+{
+int i;
+if (desc == NULL)
+return NULL;
+if (s == NULL)
+{
+s = (super_tone_rx_state_t *) malloc(sizeof(super_tone_rx_state_t) + desc->monitored_frequencies*sizeof(goertzel_state_t));
+if (s == NULL)
+return NULL;
+}
+if (callback == NULL)
+return NULL;
+for (i = 0;  i < 11;  i++)
+{
+s->segments[i].f1 = -1;
+s->segments[i].f2 = -1;
+s->segments[i].min_duration = 0;
+}
+s->segment_callback = NULL;
+s->tone_callback = callback;
+s->callback_data = user_data;
+if (desc)
+s->desc = desc;
+s->detected_tone = -1;
+s->energy = 0.0;
+s->total_energy = 0.0;
+for (i = 0;  i < desc->monitored_frequencies;  i++)
+goertzel_init(&s->state[i], &s->desc->desc[i]);
+return  s;
+}
+/*- End of function --------------------------------------------------------*/
+int super_tone_rx_free(super_tone_rx_state_t *s)
+{
+if (s)
+free(s);
+return 0;
+}
+/*- End of function --------------------------------------------------------*/
+int super_tone_rx(super_tone_rx_state_t *s, const int16_t *amp, int samples)
+{
+int i;
+int j;
+int k1;
+int k2;
+int x;
+float res[BINS/2];
+int sample;
+for (sample = 0;  sample < samples;  sample += x)
+{
+x = 0;
+for (i = 0;  i < s->desc->monitored_frequencies;  i++)
+{
+x = goertzel_update(&s->state[i],
+amp + sample,
+samples - sample);
+if (i == s->desc->monitored_frequencies - 1)
+{
+for (j = 0;  j < x;  j++)
+s->energy += amp[sample + j]*amp[sample + j];
+}
+if (s->state[i].current_sample >= s->state[i].samples)
+{
+res[i] = goertzel_result(&s->state[i]);
+goertzel_init(&s->state[i], &s->desc->desc[i]);
+if (i == s->desc->monitored_frequencies - 1)
+{
+/* Scale the energy so it can be compared to the results from the
+Goertzel filters. */
+s->total_energy = s->energy*(s->state[i].samples/2);
+s->energy = 0;
+/* Find our two best monitored frequencies, which also have adequate
+energy. */
+if (s->total_energy < THRESHOLD)
+{
+k1 = -1;
+k2 = -1;
+}
+else
+{
+if (res[0] > res[1])
+{
+k1 = 0;
+k2 = 1;
+}
+else
+{
+k1 = 1;
+k2 = 0;
+}
+for (j = 2;  j < s->desc->monitored_frequencies;  j++)
+{
+if (res[j] >= res[k1])
+{
+k2 = k1;
+k1 = j;
+}
+else if (res[j] >= res[k2])
+{
+k2 = j;
+}
+}
+if (res[k1] + res[k2] < 0.5*s->total_energy)
+{
+k1 = -1;
+k2 = -1;
+}
+else if (res[k1] > 4.0*res[k2])
+{
+k2 = -1;
+}
+else if (k2 < k1)
+{
+j = k1;
+k1 = k2;
+k2 = j;
+}
+}
+/* See if this looks different to last time */
+if (k1 != s->segments[10].f1  ||  k2 != s->segments[10].f2)
+{
+/* It is different, but this might just be a transitional quirk, or
+a one shot hiccup (eg due to noise). Only if this same thing is
+seen a second time should we change state. */
+s->segments[10].f1 = k1;
+s->segments[10].f2 = k2;
+/* While things are hopping around, consider this a continuance of the
+previous state. */
+s->segments[9].min_duration++;
+}
+else
+{
+if (k1 != s->segments[9].f1  ||  k2 != s->segments[9].f2)
+{
+if (s->detected_tone >= 0)
+{
+/* Test for the continuance of the existing tone pattern, based on our new knowledge of an
+entire segment length. */
+if (!test_cadence(s->desc->tone_list[s->detected_tone], -s->desc->tone_segs[s->detected_tone], s->segments, s->rotation++))
+{
+s->detected_tone = -1;
+s->tone_callback(s->callback_data, s->detected_tone);
+}
+}
+if (s->segment_callback)
+{
+s->segment_callback(s->callback_data,
+s->segments[9].f1,
+s->segments[9].f2,
+s->segments[9].min_duration*BINS/8);
+}
+memcpy (&s->segments[0], &s->segments[1], 9*sizeof(s->segments[0]));
+s->segments[9].f1 = k1;
+s->segments[9].f2 = k2;
+s->segments[9].min_duration = 1;
+}
+else
+{
+/* This is a continuance of the previous state */
+if (s->detected_tone >= 0)
+{
+/* Test for the continuance of the existing tone pattern. We must do this here, so we can sense the
+discontinuance of the tone on an excessively long segment. */
+if (!test_cadence(s->desc->tone_list[s->detected_tone], s->desc->tone_segs[s->detected_tone], s->segments, s->rotation))
+{
+s->detected_tone = -1;
+s->tone_callback(s->callback_data, s->detected_tone);
+}
+}
+s->segments[9].min_duration++;
+}
+}
+if (s->detected_tone < 0)
+{
+/* Test for the start of any of the monitored tone patterns */
+for (j = 0;  j < s->desc->tones;  j++)
+{
+if (test_cadence(s->desc->tone_list[j], s->desc->tone_segs[j], s->segments, -1))
+{
+s->detected_tone = j;
+s->rotation = 0;
+s->tone_callback(s->callback_data, s->detected_tone);
+break;
+}
+}
+}
+}
+}
+}
+}
+return  samples;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/

Mercurial > hg > audiostuff

comparison spandsp-0.0.3/spandsp-0.0.3/src/super_tone_rx.c @ 5:f762bf195c4b