00001 /* 00002 * SpanDSP - a series of DSP components for telephony 00003 * 00004 * private/sig_tone.h - Signalling tone processing for the 2280Hz, 2400Hz, 2600Hz 00005 * and similar signalling tone used in older protocols. 00006 * 00007 * Written by Steve Underwood <steveu@coppice.org> 00008 * 00009 * Copyright (C) 2004 Steve Underwood 00010 * 00011 * All rights reserved. 00012 * 00013 * This program is free software; you can redistribute it and/or modify 00014 * it under the terms of the GNU Lesser General Public License version 2.1, 00015 * as published by the Free Software Foundation. 00016 * 00017 * This program is distributed in the hope that it will be useful, 00018 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00019 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00020 * GNU Lesser General Public License for more details. 00021 * 00022 * You should have received a copy of the GNU Lesser General Public 00023 * License along with this program; if not, write to the Free Software 00024 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 00025 * 00026 * $Id: sig_tone.h,v 1.3 2009/04/12 14:18:02 steveu Exp $ 00027 */ 00028 00029 #if !defined(_SPANDSP_PRIVATE_SIG_TONE_H_) 00030 #define _SPANDSP_PRIVATE_SIG_TONE_H_ 00031 00032 /*! 00033 Signaling tone descriptor. This defines the working state for a 00034 single instance of the transmit and receive sides of a signaling 00035 tone processor. 00036 */ 00037 struct sig_tone_descriptor_s 00038 { 00039 /*! \brief The tones used. */ 00040 int tone_freq[2]; 00041 /*! \brief The high and low tone amplitudes. */ 00042 int tone_amp[2]; 00043 00044 /*! \brief The delay, in audio samples, before the high level tone drops 00045 to a low level tone. */ 00046 int high_low_timeout; 00047 00048 /*! \brief Some signaling tone detectors use a sharp initial filter, 00049 changing to a broader band filter after some delay. This 00050 parameter defines the delay. 0 means it never changes. */ 00051 int sharp_flat_timeout; 00052 00053 /*! \brief Parameters to control the behaviour of the notch filter, used 00054 to remove the tone from the voice path in some protocols. */ 00055 int notch_lag_time; 00056 /*! \brief TRUE if the notch may be used in the media flow. */ 00057 int notch_allowed; 00058 00059 /*! \brief The tone on persistence check, in audio samples. */ 00060 int tone_on_check_time; 00061 /*! \brief The tone off persistence check, in audio samples. */ 00062 int tone_off_check_time; 00063 00064 /*! \brief ??? */ 00065 int tones; 00066 /*! \brief The coefficients for the cascaded bi-quads notch filter. */ 00067 struct 00068 { 00069 #if defined(SPANDSP_USE_FIXED_POINT) 00070 int32_t notch_a1[3]; 00071 int32_t notch_b1[3]; 00072 int32_t notch_a2[3]; 00073 int32_t notch_b2[3]; 00074 int notch_postscale; 00075 #else 00076 float notch_a1[3]; 00077 float notch_b1[3]; 00078 float notch_a2[3]; 00079 float notch_b2[3]; 00080 #endif 00081 } tone[2]; 00082 00083 00084 #if defined(SPANDSP_USE_FIXED_POINT) 00085 /*! \brief Flat mode bandpass bi-quad parameters */ 00086 int32_t broad_a[3]; 00087 /*! \brief Flat mode bandpass bi-quad parameters */ 00088 int32_t broad_b[3]; 00089 /*! \brief Post filter scaling */ 00090 int broad_postscale; 00091 #else 00092 /*! \brief Flat mode bandpass bi-quad parameters */ 00093 float broad_a[3]; 00094 /*! \brief Flat mode bandpass bi-quad parameters */ 00095 float broad_b[3]; 00096 #endif 00097 /*! \brief The coefficients for the post notch leaky integrator. */ 00098 int32_t notch_slugi; 00099 /*! \brief ??? */ 00100 int32_t notch_slugp; 00101 00102 /*! \brief The coefficients for the post modulus leaky integrator in the 00103 unfiltered data path. The prescale value incorporates the 00104 detection ratio. This is called the guard ratio in some 00105 protocols. */ 00106 int32_t unfiltered_slugi; 00107 /*! \brief ??? */ 00108 int32_t unfiltered_slugp; 00109 00110 /*! \brief The coefficients for the post modulus leaky integrator in the 00111 bandpass filter data path. */ 00112 int32_t broad_slugi; 00113 /*! \brief ??? */ 00114 int32_t broad_slugp; 00115 00116 /*! \brief Masks which effectively threshold the notched, weighted and 00117 bandpassed data. */ 00118 int32_t notch_threshold; 00119 /*! \brief ??? */ 00120 int32_t unfiltered_threshold; 00121 /*! \brief ??? */ 00122 int32_t broad_threshold; 00123 }; 00124 00125 /*! 00126 Signaling tone transmit state 00127 */ 00128 struct sig_tone_tx_state_s 00129 { 00130 /*! \brief The callback function used to handle signaling changes. */ 00131 sig_tone_func_t sig_update; 00132 /*! \brief A user specified opaque pointer passed to the callback function. */ 00133 void *user_data; 00134 00135 /*! \brief Tone descriptor */ 00136 sig_tone_descriptor_t *desc; 00137 00138 /*! The scaling values for the high and low level tones */ 00139 int16_t tone_scaling[2]; 00140 /*! The sample timer, used to switch between the high and low level tones. */ 00141 int high_low_timer; 00142 00143 /*! The phase rates for the one or two tones */ 00144 int32_t phase_rate[2]; 00145 /*! The phase accumulators for the one or two tones */ 00146 uint32_t phase_acc[2]; 00147 00148 /*! \brief Current transmit tone */ 00149 int current_tx_tone; 00150 /*! \brief Current transmit timeout */ 00151 int current_tx_timeout; 00152 /*! \brief Time in current signaling state, in samples. */ 00153 int signaling_state_duration; 00154 }; 00155 00156 /*! 00157 Signaling tone receive state 00158 */ 00159 struct sig_tone_rx_state_s 00160 { 00161 /*! \brief The callback function used to handle signaling changes. */ 00162 sig_tone_func_t sig_update; 00163 /*! \brief A user specified opaque pointer passed to the callback function. */ 00164 void *user_data; 00165 00166 /*! \brief Tone descriptor */ 00167 sig_tone_descriptor_t *desc; 00168 00169 /*! \brief The current receive tone */ 00170 int current_rx_tone; 00171 /*! \brief The timeout for switching from the high level to low level tone detector. */ 00172 int high_low_timer; 00173 00174 struct 00175 { 00176 #if defined(SPANDSP_USE_FIXED_POINT) 00177 /*! \brief The z's for the notch filter */ 00178 int32_t notch_z1[3]; 00179 /*! \brief The z's for the notch filter */ 00180 int32_t notch_z2[3]; 00181 #else 00182 /*! \brief The z's for the notch filter */ 00183 float notch_z1[3]; 00184 /*! \brief The z's for the notch filter */ 00185 float notch_z2[3]; 00186 #endif 00187 00188 /*! \brief The z's for the notch integrators. */ 00189 int32_t notch_zl; 00190 } tone[2]; 00191 00192 #if defined(SPANDSP_USE_FIXED_POINT) 00193 /*! \brief The z's for the weighting/bandpass filter. */ 00194 int32_t broad_z[3]; 00195 #else 00196 /*! \brief The z's for the weighting/bandpass filter. */ 00197 float broad_z[3]; 00198 #endif 00199 /*! \brief The z for the broadband integrator. */ 00200 int32_t broad_zl; 00201 00202 /*! \brief ??? */ 00203 int flat_mode; 00204 /*! \brief ??? */ 00205 int tone_present; 00206 /*! \brief ??? */ 00207 int notch_enabled; 00208 /*! \brief ??? */ 00209 int flat_mode_timeout; 00210 /*! \brief ??? */ 00211 int notch_insertion_timeout; 00212 /*! \brief ??? */ 00213 int tone_persistence_timeout; 00214 00215 /*! \brief ??? */ 00216 int signaling_state_duration; 00217 }; 00218 00219 #endif 00220 /*- End of file ------------------------------------------------------------*/