spandsp 0.0.6
private/dtmf.h
1/*
2 * SpanDSP - a series of DSP components for telephony
3 *
4 * private/dtmf.h - DTMF tone generation and detection
5 *
6 * Written by Steve Underwood <steveu@coppice.org>
7 *
8 * Copyright (C) 2001, 2005 Steve Underwood
9 *
10 * All rights reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Lesser General Public License version 2.1,
14 * as published by the Free Software Foundation.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25
26#if !defined(_SPANDSP_PRIVATE_DTMF_H_)
27#define _SPANDSP_PRIVATE_DTMF_H_
28
29/*!
30 DTMF generator state descriptor. This defines the state of a single
31 working instance of a DTMF generator.
32*/
34{
35 tone_gen_state_t tones;
36 float low_level;
37 float high_level;
38 int on_time;
39 int off_time;
40 union
41 {
42 queue_state_t queue;
43 uint8_t buf[QUEUE_STATE_T_SIZE(MAX_DTMF_DIGITS)];
44 } queue;
45};
46
47/*!
48 DTMF digit detector descriptor.
49*/
51{
52 /*! Optional callback funcion to deliver received digits. */
53 digits_rx_callback_t digits_callback;
54 /*! An opaque pointer passed to the callback function. */
56 /*! Optional callback funcion to deliver real time digit state changes. */
57 tone_report_func_t realtime_callback;
58 /*! An opaque pointer passed to the real time callback function. */
60 /*! TRUE if dialtone should be filtered before processing */
62#if defined(SPANDSP_USE_FIXED_POINT)
63 /*! 350Hz filter state for the optional dialtone filter. */
64 float z350[2];
65 /*! 440Hz filter state for the optional dialtone filter. */
66 float z440[2];
67 /*! Maximum acceptable "normal" (lower bigger than higher) twist ratio. */
68 float normal_twist;
69 /*! Maximum acceptable "reverse" (higher bigger than lower) twist ratio. */
70 float reverse_twist;
71 /*! Minimum acceptable tone level for detection. */
72 int32_t threshold;
73 /*! The accumlating total energy on the same period over which the Goertzels work. */
74 int32_t energy;
75#else
76 /*! 350Hz filter state for the optional dialtone filter. */
77 float z350[2];
78 /*! 440Hz filter state for the optional dialtone filter. */
79 float z440[2];
80 /*! Maximum acceptable "normal" (lower bigger than higher) twist ratio. */
82 /*! Maximum acceptable "reverse" (higher bigger than lower) twist ratio. */
84 /*! Minimum acceptable tone level for detection. */
85 float threshold;
86 /*! The accumlating total energy on the same period over which the Goertzels work. */
87 float energy;
88#endif
89 /*! Tone detector working states for the row tones. */
90 goertzel_state_t row_out[4];
91 /*! Tone detector working states for the column tones. */
92 goertzel_state_t col_out[4];
93 /*! The result of the last tone analysis. */
94 uint8_t last_hit;
95 /*! The confirmed digit we are currently receiving */
96 uint8_t in_digit;
97 /*! The current sample number within a processing block. */
99
100 /*! Tone state duration */
102
103 /*! The number of digits which have been lost due to buffer overflows. */
105 /*! The number of digits currently in the digit buffer. */
107 /*! The received digits buffer. This is a NULL terminated string. */
108 char digits[MAX_DTMF_DIGITS + 1];
109
110 /*! \brief Error and flow logging control */
112};
113
114#endif
115/*- End of file ------------------------------------------------------------*/
struct logging_state_s logging_state_t
Definition logging.h:75
struct queue_state_s queue_state_t
Definition queue.h:54
Definition private/dtmf.h:51
float z350[2]
Definition private/dtmf.h:77
float reverse_twist
Definition private/dtmf.h:83
float threshold
Definition private/dtmf.h:85
tone_report_func_t realtime_callback
Definition private/dtmf.h:57
goertzel_state_t row_out[4]
Definition private/dtmf.h:90
void * digits_callback_data
Definition private/dtmf.h:55
goertzel_state_t col_out[4]
Definition private/dtmf.h:92
uint8_t last_hit
Definition private/dtmf.h:94
int current_digits
Definition private/dtmf.h:106
int current_sample
Definition private/dtmf.h:98
logging_state_t logging
Error and flow logging control.
Definition private/dtmf.h:111
int lost_digits
Definition private/dtmf.h:104
float z440[2]
Definition private/dtmf.h:79
float energy
Definition private/dtmf.h:87
uint8_t in_digit
Definition private/dtmf.h:96
float normal_twist
Definition private/dtmf.h:81
int filter_dialtone
Definition private/dtmf.h:61
void * realtime_callback_data
Definition private/dtmf.h:59
int duration
Definition private/dtmf.h:101
char digits[MAX_DTMF_DIGITS+1]
Definition private/dtmf.h:108
digits_rx_callback_t digits_callback
Definition private/dtmf.h:53
Definition private/dtmf.h:34
struct tone_gen_state_s tone_gen_state_t
Definition tone_generate.h:57