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 1.1 2008/11/30 13:08:42 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 int notch_allowed; 00057 00058 /*! \brief The tone on persistence check, in audio samples. */ 00059 int tone_on_check_time; 00060 /*! \brief The tone off persistence check, in audio samples. */ 00061 int tone_off_check_time; 00062 00063 int tones; 00064 /*! \brief The coefficients for the cascaded bi-quads notch filter. */ 00065 struct 00066 { 00067 #if defined(SPANDSP_USE_FIXED_POINT) 00068 int32_t notch_a1[3]; 00069 int32_t notch_b1[3]; 00070 int32_t notch_a2[3]; 00071 int32_t notch_b2[3]; 00072 int notch_postscale; 00073 #else 00074 float notch_a1[3]; 00075 float notch_b1[3]; 00076 float notch_a2[3]; 00077 float notch_b2[3]; 00078 #endif 00079 } tone[2]; 00080 00081 00082 /*! \brief Flat mode bandpass bi-quad parameters */ 00083 #if defined(SPANDSP_USE_FIXED_POINT) 00084 int32_t broad_a[3]; 00085 int32_t broad_b[3]; 00086 int broad_postscale; 00087 #else 00088 float broad_a[3]; 00089 float broad_b[3]; 00090 #endif 00091 /*! \brief The coefficients for the post notch leaky integrator. */ 00092 int32_t notch_slugi; 00093 int32_t notch_slugp; 00094 00095 /*! \brief The coefficients for the post modulus leaky integrator in the 00096 unfiltered data path. The prescale value incorporates the 00097 detection ratio. This is called the guard ratio in some 00098 protocols. */ 00099 int32_t unfiltered_slugi; 00100 int32_t unfiltered_slugp; 00101 00102 /*! \brief The coefficients for the post modulus leaky integrator in the 00103 bandpass filter data path. */ 00104 int32_t broad_slugi; 00105 int32_t broad_slugp; 00106 00107 /*! \brief Masks which effectively threshold the notched, weighted and 00108 bandpassed data. */ 00109 int32_t notch_threshold; 00110 int32_t unfiltered_threshold; 00111 int32_t broad_threshold; 00112 }; 00113 00114 struct sig_tone_tx_state_s 00115 { 00116 /*! \brief The callback function used to handle signaling changes. */ 00117 sig_tone_func_t sig_update; 00118 /*! \brief A user specified opaque pointer passed to the callback function. */ 00119 void *user_data; 00120 00121 sig_tone_descriptor_t *desc; 00122 00123 /*! The scaling values for the high and low level tones */ 00124 int32_t tone_scaling[2]; 00125 /*! The sample timer, used to switch between the high and low level tones. */ 00126 int high_low_timer; 00127 00128 /*! The phase rates for the one or two tones */ 00129 int32_t phase_rate[2]; 00130 /*! The phase accumulators for the one or two tones */ 00131 uint32_t phase_acc[2]; 00132 00133 int current_tx_tone; 00134 int current_tx_timeout; 00135 int signaling_state_duration; 00136 }; 00137 00138 struct sig_tone_rx_state_s 00139 { 00140 /*! \brief The callback function used to handle signaling changes. */ 00141 sig_tone_func_t sig_update; 00142 /*! \brief A user specified opaque pointer passed to the callback function. */ 00143 void *user_data; 00144 00145 sig_tone_descriptor_t *desc; 00146 00147 int current_rx_tone; 00148 int high_low_timer; 00149 00150 struct 00151 { 00152 /*! \brief The z's for the notch filter */ 00153 #if defined(SPANDSP_USE_FIXED_POINT) 00154 int32_t notch_z1[3]; 00155 int32_t notch_z2[3]; 00156 #else 00157 float notch_z1[3]; 00158 float notch_z2[3]; 00159 #endif 00160 00161 /*! \brief The z's for the notch integrators. */ 00162 int32_t notch_zl; 00163 } tone[2]; 00164 00165 /*! \brief The z's for the weighting/bandpass filter. */ 00166 #if defined(SPANDSP_USE_FIXED_POINT) 00167 int32_t broad_z[3]; 00168 #else 00169 float broad_z[3]; 00170 #endif 00171 /*! \brief The z for the broadband integrator. */ 00172 int32_t broad_zl; 00173 00174 int flat_mode; 00175 int tone_present; 00176 int notch_enabled; 00177 int flat_mode_timeout; 00178 int notch_insertion_timeout; 00179 int tone_persistence_timeout; 00180 00181 int signaling_state_duration; 00182 }; 00183 00184 #endif 00185 /*- End of file ------------------------------------------------------------*/